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Note: This page contains sample records for the topic "high voltage direct" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

A High Voltage Direct Current Generator  

Science Journals Connector (OSTI)

When powdered materials are blown through metal tubes by means of compressed air considerable quantities of electricity are produced by contact electrification. It was found that 6×10-5 coulombs could be produced per gram of diatomaceous earth, a form of silica, blown through a short length of copper tube. A generator of extremely high voltage is proposed, and a small scale model of such a generator is described, by means of which currents of 8×10-5 amperes at 260 kilovolts were generated.

Richard E. Vollrath

1932-10-15T23:59:59.000Z

2

Summary of multiterminal high-voltage direct current transmission technology  

SciTech Connect (OSTI)

This report summarizes the present state of multiterminal (MT) high-voltage direct current (HVDC) power transmission. The purpose is to reassess the need for HVDC circuit breakers and to identify needed research for MT HVDC. The fundamentals of this technology are presented, and previous research and development is reviewed. Although no MT HVDC systems have yet been built, many concepts have been proposed. Some require a dc breaker, and others do not. Both options have advantages and disadvantages for various applications, so the selection will depend on the proposed application. Research is needed to define operating characteristics of various MT HVDC systems. In some applications, dc breakers will be useful, so research into HVDC interruption should continue. Also, dc fault detection and control algorithms for MT systems should be studied.

Biggs, R.B.; Jewell, W.T.

1984-05-01T23:59:59.000Z

3

An Annotated Bibliography of High-Voltage Direct-Current Transmission and Flexible AC Transmission (FACTS) Devices, 1991-1993.  

SciTech Connect (OSTI)

References are contained for HVDC systems, converter stations and components, overhead transmission lines, cable transmission, system design and operations, simulation of high voltage direct current systems, high-voltage direct current installations, and flexible AC transmission system (FACTS).

Litzenberger, Wayne; Lava, Val

1994-08-01T23:59:59.000Z

4

Partial discharge measurements on a high voltage direct current mass impregnated paper cable  

SciTech Connect (OSTI)

Partial discharge measurement has been a good tool for the quality assurance of cables under alternating voltage. With the growing interest in High Voltage Direct Current cables it seems therefore logical to extend this technique for use at direct voltage. The paper describes this technique as used on a HVDC cable with mass impregnated paper. The different phases of operation (no load, full load, cooling phase, etc.) are characterized by a different discharge behavior. Special attention is given to the dangerous cooling phase. Models have been developed which can explain the discharge patterns that were measured. This paper gives an insight in the electrical behavior of a HVDC cable with mass impregnated paper insulation.

Jeroense, M.J.P. [NKF KABEL B.V., Delft (Netherlands); Kreuger, F.H. [Delft Univ. of Technology (Netherlands)

1996-12-31T23:59:59.000Z

5

Connecting Renewables Directly to the Grid: Resilient Multi-Terminal HVDC Networks with High-Voltage High-Frequency Electronics  

SciTech Connect (OSTI)

GENI Project: GE is developing electricity transmission hardware that could connect distributed renewable energy sources, like wind farms, directly to the grid—eliminating the need to feed the energy generated through intermediate power conversion stations before they enter the grid. GE is using the advanced semiconductor material silicon carbide (SiC) to conduct electricity through its transmission hardware because SiC can operate at higher voltage levels than semiconductors made out of other materials. This high-voltage capability is important because electricity must be converted to high-voltage levels before it can be sent along the grid’s network of transmission lines. Power companies do this because less electricity is lost along the lines when the voltage is high.

None

2012-01-23T23:59:59.000Z

6

Recommended practice for fire protection for electric generating plants and high voltage direct current converter stations. 2005 ed.  

SciTech Connect (OSTI)

The standard outlines fire safety recommendations for gas, oil, coal, and alternative fuel electric generating plants including high voltage direct current converter stations and combustion turbine units greater than 7500 hp used for electric generation. Provisions apply to both new and existing plants. The document provides fire prevention and fire protection recommendations for the: safety of construction and operating personnel; physical integrity of plant components; and continuity of plant operations. The 2005 edition includes revisions and new art that clarify existing provisions. 5 annexes.

NONE

2005-07-01T23:59:59.000Z

7

High-voltage engineering  

E-Print Network [OSTI]

High-voltage engineering covers the application, the useful use and proper working of high voltages and high fields. Here we give some introductory examples, i.e., ‘septa’ and ‘kicker’ at the Large Hadron Collider (14 TeV), the Super Proton Synchrotron (450 GeV) and the Proton Synchrotron (26 GeV) accelerators as found at the European Orginization for Nuclear Research (CERN) today. We briefly cover the theoretical foundation (Maxwell equations) and aspects of numerical field simulation methods. Concepts relating to electrical fields, insulation geometry and medium and breakdown are introduced. We discuss ways of generating high voltages with examples of AC sources (50/60 Hz), DC sources, and pulse sources. Insulation and breakdown in gases, liquids, solids and vacuum are presented, including Paschen’s law (breakdown field and streamer breakdown). Applications of the above are discussed, in particular the general application of a transformer. We briefly discuss measurement techniques of partial disch...

Gaxiola, E

2006-01-01T23:59:59.000Z

8

High voltage pulse conditioning  

DOE Patents [OSTI]

Apparatus for conditioning high voltage pulses from particle accelerators in order to shorten the rise times of the pulses. Flashover switches in the cathode stalk of the transmission line hold off conduction for a determinable period of time, reflecting the early portion of the pulses. Diodes upstream of the switches divert energy into the magnetic and electrostatic storage of the capacitance and inductance inherent to the transmission line until the switches close.

Springfield, Ray M. (Sante Fe, NM); Wheat, Jr., Robert M. (Los Alamos, NM)

1990-01-01T23:59:59.000Z

9

High voltage DC power supply  

DOE Patents [OSTI]

A high voltage DC power supply having a first series resistor at the output for limiting current in the event of a short-circuited output, a second series resistor for sensing the magnitude of output current, and a voltage divider circuit for providing a source of feedback voltage for use in voltage regulation is disclosed. The voltage divider circuit is coupled to the second series resistor so as to compensate the feedback voltage for a voltage drop across the first series resistor. The power supply also includes a pulse-width modulated control circuit, having dual clock signals, which is responsive to both the feedback voltage and a command voltage, and also includes voltage and current measuring circuits responsive to the feedback voltage and the voltage developed across the second series resistor respectively. 7 figs.

Droege, T.F.

1989-12-19T23:59:59.000Z

10

High voltage DC power supply  

DOE Patents [OSTI]

A high voltage DC power supply having a first series resistor at the output for limiting current in the event of a short-circuited output, a second series resistor for sensing the magnitude of output current, and a voltage divider circuit for providing a source of feedback voltage for use in voltage regulation is disclosed. The voltage divider circuit is coupled to the second series resistor so as to compensate the feedback voltage for a voltage drop across the first series resistor. The power supply also includes a pulse-width modulated control circuit, having dual clock signals, which is responsive to both the feedback voltage and a command voltage, and also includes voltage and current measuring circuits responsive to the feedback voltage and the voltage developed across the second series resistor respectively.

Droege, Thomas F. (Batavia, IL)

1989-01-01T23:59:59.000Z

11

Peak Power Bi-directional Transfer From High Speed Flywheel to Electrical Regulated Bus Voltage System  

E-Print Network [OSTI]

were performed to determine the energy transfer capabilities of a flywheel coupled high speed permanent magnet synchronous machine through the proposed system's energy storage tank. Results are presented

Szabados, Barna

12

Epidemiologic study of Holstein dairy cow performance and reproduction near a high-voltage direct - current powerline  

SciTech Connect (OSTI)

The development and operation of a high-voltage direct-current (HVDC) transmission line in rural Minnesota generated public concern over potential adverse effects to nearby residents and their livestock. Electrical parameters near an HVDC line decline rapidly with distance, but effects on ambient space charge have been detected out to 1 mile. To identify potential adverse effects of HVDC line operation on livestock, case-control and cohort study methods were used to examine various indices of Holstein performance in relation to distance from the line and the onset of line operation. It was believed that these indices would reflect changes in physiologic function or overt health effects that might arise from the HVDC environment. High-quality performance data from existing Dairy Herd Improvement Association (DHIA) records were obtained for 97% of qualifying herds located within 10 miles of the line. The large number of animals and years of observation provided high statistical power to detect even small systematic changes in performance. No significant differences in milk production or reproductive capacity were associated with presumed exposure to the HVDC environment. The absence of measurable effects in a large sentinel animal population may have implications for the assessment of human health risks related to HVDC transmission lines.

Martin, F.B.; Bender, A.; Steuernagel, G.; Robinson, R.A.; Revsbech, R.; Sorensen, D.K.; Williamson, N.; Williams, A.

1986-01-01T23:59:59.000Z

13

High voltage RF feedthrough bushing  

DOE Patents [OSTI]

Described is a multi-element, high voltage radio frequency bushing for trmitting RF energy to an antenna located in a vacuum container. The bushing includes a center conductor of complex geometrical shape, an outer coaxial shield conductor, and a thin-walled hollow truncated cone insulator disposed between central and outer conductors. The shape of the center conductor, which includes a reverse curvature portion formed of a radially inwardly directed shoulder and a convex portion, controls the uniformity of the axial surface gradient on the insulator cone. The outer shield has a first substantially cylindrical portion and a second radially inwardly extending truncated cone portion.

Grotz, Glenn F. (Huntington Station, NY)

1984-01-01T23:59:59.000Z

14

Temperature controlled high voltage regulator  

DOE Patents [OSTI]

A temperature controlled high voltage regulator for automatically adjusting the high voltage applied to a radiation detector is described. The regulator is a solid state device that is independent of the attached radiation detector, enabling the regulator to be used by various models of radiation detectors, such as gas flow proportional radiation detectors.

Chiaro, Jr., Peter J. (Clinton, TN); Schulze, Gerald K. (Knoxville, TN)

2004-04-20T23:59:59.000Z

15

ABBGroup-1-High voltage lab  

E-Print Network [OSTI]

;©ABBGroup-3- 3-Sep-07 Where does one use circuit breakers? High voltage (HV) circuit breakers are keyA DISTRIBUTION MEDIUM AND LOW VOLTAGE HV circuit breakers #12;©ABBGroup-4- 3-Sep-07 When a breaker fails to interrupt the current... Fault arc at a disconnector Fault arc in a substation #12;©ABBGroup-5- 3-Sep-07

Basse, Nils Plesner

16

A 4000-A HVDC (high-voltage direct-current) circuit breaker with fast fault-clearing capability: Final report  

SciTech Connect (OSTI)

This project is a follow-up of the first development of a 500 kV HVDC airblast circuit breaker (EPRI project 1507-3). The objective was to increase the current interrupting capability from 2200 A to 4000 A and shorten its fault clearing time. A high current 500 kV HVDC circuit breaker has been built using the passive commutation circuit. The breaker is modular in construction and can be designed for a wide variety of system conditions. More than 400 current interruptions were carried out successfully. Tests have shown that this circuit breaker is capable of interrupting more than 4000 A dc. Practical breakers with current interrupting capability of even 5500 A dc could be built. The circuit breaker operation and the fault-clearing process can be materially speeded up if the trip signal is given as soon as the fault is detected and without waiting for the current levels to come down in response to converter control action. The new dc breakers are shown to be capable of withstanding these transient arc currents of 8000 A without affecting its ability to interrupt the direct current that follows the transient. This transient current withstand capability is greater than is likely to occur during dc faults. The fault clearing time of this HVDC circuit breaker is comparable to the fault clearing time of conventional ac breakers for ac faults. The developed HVDC circuit breaker is now commercially available and can be supplied for use in HVDC systems. Its use in such systems is expected to provide flexibility in system design and contribute to system stability. 38 refs., 52 figs., 9 tabs.

Not Available

1988-04-01T23:59:59.000Z

17

Measurement of high voltage using Rutherford backscattering spectrometry  

E-Print Network [OSTI]

A novel variation of Rutherford Backscattering Spectrometry (RBS) has been utilized to measure a high voltage collected on an aluminum target by Direct Energy Conversion. The maximum high voltage on the target was measured to be 97.5 kV +/- 2 kV...

Abrego, Celestino Pete

2007-04-25T23:59:59.000Z

18

High Voltage Electrolyte for Lithium Batteries  

Broader source: Energy.gov (indexed) [DOE]

battery using high voltage high energy cathode materials to enable large-scale, cost competitive production of the next generation of electric-drive vehicles. To...

19

High voltage load resistor array  

DOE Patents [OSTI]

A high voltage resistor comprising an array of a plurality of parallel electrically connected resistor elements each containing a resistive solution, attached at each end thereof to an end plate, and about the circumference of each of the end plates, a corona reduction ring. Each of the resistor elements comprises an insulating tube having an electrode inserted into each end thereof and held in position by one or more hose clamps about the outer periphery of the insulating tube. According to a preferred embodiment, the electrode is fabricated from stainless steel and has a mushroom shape at one end, that inserted into the tube, and a flat end for engagement with the end plates that provides connection of the resistor array and with a load.

Lehmann, Monty Ray (Smithfield, VA)

2005-01-18T23:59:59.000Z

20

Development of High Voltage Electron Microscope  

Science Journals Connector (OSTI)

......Cockcroft Walton Type High Voltage Generator. O Power Line O Fig. 4...pressure in the tank to the atmospheric pressure by removing freon...pump using liquid nitrogen. Water buffer and liquid nitrogen...base plate of high voltage generator. Four poles stand on this......

Shinjiro KATAGIRI; Hirokazu KIMURA; Susumu OZASA; Kazumi SHIRAISHI

1969-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage direct" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Limitations of High-Voltage Insulation  

Science Journals Connector (OSTI)

... materials such as impregnated paper. The important electrical properties of the materials used for the insulation of high-voltage circuits are conductivity and electric strength. The conductivity measures the ability ... a million times between themselves, but they are all classified as available for high-voltage insulation.

1938-01-08T23:59:59.000Z

22

High Voltage Safety Act | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

High Voltage Safety Act High Voltage Safety Act High Voltage Safety Act < Back Eligibility Commercial Construction Developer General Public/Consumer Industrial Installer/Contractor Utility Savings Category Alternative Fuel Vehicles Hydrogen & Fuel Cells Buying & Making Electricity Water Home Weatherization Solar Wind Program Info State Georgia Program Type Safety and Operational Guidelines Siting and Permitting The purpose of the High Voltage Safety Act is to prevent injury to persons and property and interruptions of utility service resulting from accidental or inadvertent contact with high-voltage electric lines by providing that no work shall be done in the vicinity of such lines unless and until the owner or operator thereof has been notified of such work and has taken the appropriate safety measures. The Georgia Public Service Commission requires

23

ABBGroup-1-High voltage lab  

E-Print Network [OSTI]

A DISTRIBUTION MEDIUM AND LOW VOLTAGE HV circuit breakers #12;©ABBGroup-4- 3-Sep-07 When a breaker fails to interrupt the current... Fault arc at a disconnector Fault arc in a substation #12;©ABBGroup-5- 3-Sep-07/costs A detailed understanding of arc physics and fluid dynamics is necessary for the development of HV circuit

Basse, Nils Plesner

24

Vehicle Technologies Office Merit Review 2014: High-Voltage Solid...  

Broader source: Energy.gov (indexed) [DOE]

High-Voltage Solid Polymer Batteries for Electric Drive Vehicles Vehicle Technologies Office Merit Review 2014: High-Voltage Solid Polymer Batteries for Electric Drive Vehicles...

25

High-Voltage Solid Polymer Batteries for Electric Drive Vehicles...  

Broader source: Energy.gov (indexed) [DOE]

High-Voltage Solid Polymer Batteries for Electric Drive Vehicles High-Voltage Solid Polymer Batteries for Electric Drive Vehicles 2013 DOE Hydrogen and Fuel Cells Program and...

26

High-Voltage Solid Polymer Batteries for Electric Drive Vehicles...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

High-Voltage Solid Polymer Batteries for Electric Drive Vehicles High-Voltage Solid Polymer Batteries for Electric Drive Vehicles 2012 DOE Hydrogen and Fuel Cells Program and...

27

Modular high voltage power supply for chemical analysis  

DOE Patents [OSTI]

A high voltage power supply for use in a system such as a microfluidics system, uses a DC-DC converter in parallel with a voltage-controlled resistor. A feedback circuit provides a control signal for the DC-DC converter and voltage-controlled resistor so as to regulate the output voltage of the high voltage power supply, as well as, to sink or source current from the high voltage supply.

Stamps, James F. (Livermore, CA); Yee, Daniel D. (Dublin, CA)

2010-05-04T23:59:59.000Z

28

High voltage overhead long transmission line design and fault analysis.  

E-Print Network [OSTI]

??The goal of this project is to design a reliable high voltage overhead long transmission line that satisfies specific design criteria including voltage regulation, efficiency,… (more)

Elzain, Mohamed Ali

2011-01-01T23:59:59.000Z

29

High voltage stability performance of a gamma ray detection device  

SciTech Connect (OSTI)

An industrial grade digital radiation survey meter device is currently being developed at Malaysian Nuclear Agency. This device used a cylindrical type Geiger Mueller (GM) which acts as a detector. GM detector operates at relatively high direct current voltages depend on the type of GM tube. This thin/thick walled cylindrical type of GM tube operates at 450-650 volts range. Proper value and stability performance of high voltage are important parameters to ensure that this device give a reliable radiation dose measurement. This paper will present an assessment of the stability and performance of the high voltage supply for radiation detector. The assessment is performed using System Identification tools box in MATLAB and mathematical statistics.

Abdullah, Nor Arymaswati; Lombigit, Lojius; Rahman, Nur Aira Abd [Technical Support Division, Malaysian Nuclear Agency, 43000 Kajang, Selangor (Malaysia)

2014-02-12T23:59:59.000Z

30

Electro-optic high voltage sensor  

DOE Patents [OSTI]

A small sized electro-optic voltage sensor capable of accurate measurement of high levels of voltages without contact with a conductor or voltage source is provided. When placed in the presence of an electric field, the sensor receives an input beam of electromagnetic radiation into the sensor. A polarization beam displacer serves as a filter to separate the input beam into two beams with orthogonal linear polarizations. The beam displacer is oriented in such a way as to rotate the linearly polarized beams such that they enter a Pockels crystal having at a preferred angle of 45 degrees. The beam displacer is therefore capable of causing a linearly polarized beam to impinge a crystal at a desired angle independent of temperature. The Pockels electro-optic effect induces a differential phase shift on the major and minor axes of the input beam as it travels through the Pockels crystal, which causes the input beam to be elliptically polarized. A reflecting prism redirects the beam back through the crystal and the beam displacer. On the return path, the polarization beam displacer separates the elliptically polarized beam into two output beams of orthogonal linear polarization representing the major and minor axes. The system may include a detector for converting the output beams into electrical signals, and a signal processor for determining the voltage based on an analysis of the output beams. The output beams are amplitude modulated by the frequency of the electric field and the amplitude of the output beams is proportional to the magnitude of the electric field, which is related to the voltage being measured.

Davidson, James R. (Idaho Falls, ID); Seifert, Gary D. (Idaho Falls, ID)

2002-01-01T23:59:59.000Z

31

High voltage electric substation performance in earthquakes  

SciTech Connect (OSTI)

This paper examines the performance of several types of high voltage substation equipment in past earthquakes. Damage data is provided in chart form. This data is then developed into a tool for estimating the performance of a substation subjected to an earthquake. First, suggests are made about the development of equipment class fragility curves that represent the expected earthquake performance of different voltages and types of equipment. Second, suggestions are made about how damage to individual pieces of equipment at a substation likely affects the post-earthquake performance of the substation as a whole. Finally, estimates are provided as to how quickly a substation, at various levels of damage, can be restored to operational service after the earthquake.

Eidinger, J. [G and E Engineering Systems, Oakland, CA (United States); Ostrom, D. [Southern California Edison, Rosemead, CA (United States); Matsuda, E. [Pacific Gas and Electric, San Francisco, CA (United States)

1995-12-31T23:59:59.000Z

32

Fiber optic current monitor for high-voltage applications  

DOE Patents [OSTI]

A current monitor which derives its power from the conductor being measured for bidirectionally measuring the magnitude of current (from DC to above 50 khz) flowing through a conductor across which a relatively high level DC voltage is applied, includes a pair of identical transmitter modules connected in opposite polarity to one another in series with the conductor being monitored, for producing from one module a first light signal having an intensity directly proportional to the magnitude of current flowing in one direction through the conductor during one period of time, and from the other module a second light signal having an intensity directly proportional to the magnitude of current flowing in the opposite direction through the conductor during another period of time, and a receiver located in a safe area remote from the high voltage area for receiving the first and second light signals, and converting the same to first and second voltage signals having levels indicative of the magnitude of current being measured at a given time.

Renda, George F. (Plainsboro, NJ)

1992-01-01T23:59:59.000Z

33

Control of Analyte Electrolysis in Electrospray Ionization Mass Spectrometry Using Repetitively Pulsed High Voltage  

SciTech Connect (OSTI)

Analyte electrolysis using a repetitively pulsed high voltage ion source was investigated and compared to that using a regular, continuously operating direct current high voltage ion source in electrospray ionization mass spectrometry. The extent of analyte electrolysis was explored as a function of the length and frequency of the high voltage pulse using the model compound reserpine in positive ion mode. Using +5 kV as the maximum high voltage amplitude, reserpine was oxidized to its 2, 4, 6 and 8-electron oxidation products when direct current high voltage was employed. In contrast, when using a pulsed high voltage, oxidation of reserpine was eliminated by employing the appropriate high voltage pulse length and frequency. This effect was caused by inefficient mass transport of the analyte to the electrode surface during the duration of the high voltage pulse and the subsequent relaxation of the emitter electrode/ electrolyte interface during the time period when the high voltage was turned off. This mode of ESI source operation allows for analyte electrolysis to be quickly and simply switched on or off electronically via a change in voltage pulse variables.

Kertesz, Vilmos [ORNL; Van Berkel, Gary J [ORNL

2011-01-01T23:59:59.000Z

34

Safe epoxy encapsulant for high voltage magnetics  

SciTech Connect (OSTI)

This paper describes the use of Formula 456, an aliphatic amine cured epoxy for impregnating coils and high voltage transformers. Sandia has evaluated a number of MDA-free epoxy encapsulants which relied on either anhydride or other aromatic amine curing agents. The use of aliphatic amine curing agents was more recently evaluated and has resulted in the definition of Formula 456 resin. Methylene dianiline (MDA) has been used for more than 20 years as the curing agent for various epoxy formulations throughout the Department of Energy and much of industry. Sandia National Laboratories began the process of replacing MDA with other formulations because of regulations imposed by OSHA on the use of MDA. OSHA has regulated MDA because it is a suspect carcinogen. Typically the elimination of OSHA-regulated materials provides a rare opportunity to qualify new formulations in a range of demanding applications. It was important to take full advantage of that opportunity, although the associated materials qualification effort was costly. Small high voltage transformers are one of those demanding applications. The successful implementation of the new formulation for high reliability transformers will be described. The test results that demonstrate the parts are qualified for use in DOE weapon systems will be presented.

Sanchez, R.O.; Archer, W.E.

1998-01-01T23:59:59.000Z

35

Accelerator System Development at High Voltage Engineering  

SciTech Connect (OSTI)

Throughout the years, HVE has continuously extended the capabilities of its accelerator systems to meet the rising demands from a diverse field of applications, among which are deep level ion implantation, micro-machining, neutron production for biomedical research, isotope production or accelerator mass spectrometry. Characteristic for HVE accelerators is the coaxial construction of the all solid state power supply around the acceleration tubes. With the use of solid state technology, the accelerators feature high stability and very low ripple. Terminal voltages range from 1 to 6 MV for HVE Singletrons and Tandetrons. The high-current versions of these accelerators can provide ion beams with powers of several kW. In the last years, several systems have been built with terminal voltages of 1.25 MV, 2 MV and 5 MV. Recently, the first system based on a 6 MV Tandetron has passed the factory tests. In this paper we describe the characteristics of the HVE accelerator systems and present as example recent systems.

Klein, M. G.; Gottdang, A.; Haitsma, R. G.; Mous, D. J. W. [High Voltage Engineering Europa B.V., P.O. Box 99, Amersfoort 3800 AB (Netherlands)

2009-03-10T23:59:59.000Z

36

Low voltage amplifier architecture for high speed switched capacitor circuits  

E-Print Network [OSTI]

This work concentrates on circuit realization of high speed and low voltage switched capacitor circuits, with emphasis on the operational transconductance amplifier (OTA). An overview of switched capacitor circuits is given. Speed and voltage...

Shankar, Asit

2012-06-07T23:59:59.000Z

37

High-voltage R-F feedthrough bushing  

DOE Patents [OSTI]

Described is a multi-element, high voltage radio frequency bushing for transmitting rf energy to an antenna located in a vacuum container. The bushing includes a center conductor of complex geometrical shape, an outer coaxial shield conductor, and a thin-walled hollow truncated cone insulator disposed between central and outer conductors. The shape of the center conductor, which includes a reverse curvature portion formed of a radially inwardly directed shoulder and a convex portion, controls the uniformity of the axial surface gradient on the insulator cone. The outer shield has a first substantially cylindrical portion and a second radially inwardly extending truncated cone portion.

Grotz, G.F.

1982-09-03T23:59:59.000Z

38

fault diagnosis of a high voltage transmission line using waveform ...  

E-Print Network [OSTI]

Oct 4, 2013 ... FAULT DIAGNOSIS OF A HIGH VOLTAGE TRANSMISSION LINE USING ... Fault types such as single line to ground, line to line, double line to ...

Ripunjoy Phukan

2013-10-04T23:59:59.000Z

39

Radio-frequency powered glow discharge device and method with high voltage interface  

DOE Patents [OSTI]

A high voltage accelerating potential, which is supplied by a high voltage direct current power supply, is applied to the electrically conducting interior wall of an RF powered glow discharge cell. The RF power supply desirably is electrically grounded, and the conductor carrying the RF power to the sample held by the probe is desirably shielded completely excepting only the conductor's terminal point of contact with the sample. The high voltage DC accelerating potential is not supplied to the sample. A high voltage capacitance is electrically connected in series between the sample on the one hand and the RF power supply and an impedance matching network on the other hand. The high voltage capacitance isolates the high DC voltage from the RF electronics, while the RF potential is passed across the high voltage capacitance to the plasma. An inductor protects at least the RF power supply, and desirably the impedance matching network as well, from a short that might occur across the high voltage capacitance. The discharge cell and the probe which holds the sample are configured and disposed to prevent the probe's components, which are maintained at ground potential, from bridging between the relatively low vacuum region in communication with the glow discharge maintained within the cell on the one hand, and the relatively high vacuum region surrounding the probe and cell on the other hand. The probe and cell also are configured and disposed to prevent the probe's components from electrically shorting the cell's components. 11 figures.

Duckworth, D.C.; Marcus, R.K.; Donohue, D.L.; Lewis, T.A.

1994-06-28T23:59:59.000Z

40

The Cavendish high-voltage laboratory 1935–39  

Science Journals Connector (OSTI)

...the period covered. Nuclear Transmutation|Cavendish...development of high-voltage nuclear transmutation equipment...experimental work in nuclear physics though he continued...a new high-voltage accelerator therefore fell mainly...doubler circuit with six vacuum rectifiers forming a...

1999-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage direct" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Living and Working Safely Around High-Voltage Power Lines.  

SciTech Connect (OSTI)

High-voltage transmission lines can be just as safe as the electrical wiring in the homes--or just as dangerous. The crucial factor is ourselves: they must learn to behave safely around them. This booklet is a basic safety guide for those who live and work around power lines. It deals primarily with nuisance shocks due to induced voltages, and with potential electric shock hazards from contact with high-voltage lines. References on possible long-term biological effects of transmission lines are shown. In preparing this booklet, the Bonneville Power Administration has drawn on more than 50 years of experience with high-voltage transmission. BPA operates one of the world`s largest networks of long-distance, high-voltage lines. This system has more than 400 substations and about 15,000 miles of transmission lines, almost 4,400 miles of which are operated at 500,000 volts.

United States. Bonneville Power Administration.

2001-06-01T23:59:59.000Z

42

Electrical system architecture having high voltage bus  

DOE Patents [OSTI]

An electrical system architecture is disclosed. The architecture has a power source configured to generate a first power, and a first bus configured to receive the first power from the power source. The architecture also has a converter configured to receive the first power from the first bus and convert the first power to a second power, wherein a voltage of the second power is greater than a voltage of the first power, and a second bus configured to receive the second power from the converter. The architecture further has a power storage device configured to receive the second power from the second bus and deliver the second power to the second bus, a propulsion motor configured to receive the second power from the second bus, and an accessory motor configured to receive the second power from the second bus.

Hoff, Brian Douglas (East Peoria, IL); Akasam, Sivaprasad (Peoria, IL)

2011-03-22T23:59:59.000Z

43

E-beam high voltage switching power supply  

DOE Patents [OSTI]

A high-power power supply produces a controllable, constant high voltage put under varying and arcing loads. The power supply includes a voltage regulator, an inductor, an inverter for producing a high frequency square wave current of alternating polarity, an improved inverter voltage clamping circuit, a step up transformer, an output rectifier for producing a dc voltage at the output of each module, and a current sensor for sensing output current. The power supply also provides dynamic response to varying loads by controlling the voltage regulator duty cycle and circuitry is provided for sensing incipient arc currents at the output of the power supply to simultaneously decouple the power supply circuitry from the arcing load. The power supply includes a plurality of discrete switching type dc--dc converter modules.

Shimer, Daniel W. (Danville, CA); Lange, Arnold C. (Livermore, CA)

1996-01-01T23:59:59.000Z

44

E-beam high voltage switching power supply  

DOE Patents [OSTI]

A high-power power supply produces a controllable, constant high voltage output under varying and arcing loads. The power supply includes a voltage regulator, an inductor, an inverter for producing a high frequency square wave current of alternating polarity, an improved inverter voltage clamping circuit, a step up transformer, an output rectifier for producing a dc voltage at the output of each module, and a current sensor for sensing output current. The power supply also provides dynamic response to varying loads by controlling the voltage regulator duty cycle and circuitry is provided for sensing incipient arc currents at the output of the power supply to simultaneously decouple the power supply circuitry from the arcing load. The power supply includes a plurality of discrete switching type dc--dc converter modules. 5 figs.

Shimer, D.W.; Lange, A.C.

1996-10-15T23:59:59.000Z

45

High-voltage air-core pulse transformers  

SciTech Connect (OSTI)

General types of air core pulse transformers designed for high voltage pulse generation and energy transfer applications are discussed with special emphasis on pulse charging systems which operate up to the multi-megavolt range. The design, operation, dielectric materials, and performance are described. It is concluded that high voltage air core pulse transformers are best suited to applications outside the normal ranges of conventional magnetic core transformers. In general these include charge transfer at high power levels and fast pulse generation with comparatively low energy. When properly designed and constructed, they are capable of delivering high energy transfer efficiency and have demonstrated superior high voltage endurance. The principal disadvantage of high voltage air core transformers is that they are not generally available from commercial sources. Consequently, the potential user must become thoroughly familiar with all aspects of design, fabrication and system application before he can produce a high performance transformer system. (LCL)

Rohwein, G. J.

1981-01-01T23:59:59.000Z

46

Optically triggered high voltage switch network and method for switching a high voltage  

DOE Patents [OSTI]

An optically triggered solid state switch and method for switching a high voltage electrical current. A plurality of solid state switches (350) are connected in series for controlling electrical current flow between a compensation capacitor (112) and ground in a reactive power compensator (50, 50') that monitors the voltage and current flowing through each of three distribution lines (52a, 52b and 52c), which are supplying three-phase power to one or more inductive loads. An optical transmitter (100) controlled by the reactive power compensation system produces light pulses that are conveyed over optical fibers (102) to a switch driver (110') that includes a plurality of series connected optical triger circuits (288). Each of the optical trigger circuits controls a pair of the solid state switches and includes a plurality of series connected resistors (294, 326, 330, and 334) that equalize or balance the potential across the plurality of trigger circuits. The trigger circuits are connected to one of the distribution lines through a trigger capacitor (340). In each switch driver, the light signals activate a phototransistor (300) so that an electrical current flows from one of the energy reservoir capacitors through a pulse transformer (306) in the trigger circuit, producing gate signals that turn on the pair of serially connected solid state switches (350).

El-Sharkawi, Mohamed A. (Renton, WA); Andexler, George (Everett, WA); Silberkleit, Lee I. (Mountlake Terrace, WA)

1993-01-19T23:59:59.000Z

47

High-voltage supply for backward-wave tube  

SciTech Connect (OSTI)

A high-current high-voltage supply for a backward-wave tube is described that uses a generalppurpose semiconductor converter with pulse-width modulation and two-stage regulation. The load current is up to 250 mA for load voltages of from 0.5 to 4.5 kV. The voltage staiblity is less than or equal to 5 x 10/sup -6/. the root-mean-square output ripple is less than or equal to 2 x 10/sup -6// The supply is equipped with high-speed (5 usec) load-breakdown protection.

Bryvkhanov, A.N.; Kosarev, P.M.; Latushkin, S.T.; Yudin, L.I.

1986-04-01T23:59:59.000Z

48

High Voltage Electrolytes for Li-ion Batteries | Department of...  

Broader source: Energy.gov (indexed) [DOE]

Electrolytes for Li-ion Batteries High Voltage Electrolytes for Li-ion Batteries 2011 DOE Hydrogen and Fuel Cells Program, and Vehicle Technologies Program Annual Merit Review and...

49

High Voltage Electrolytes for Li-ion Batteries | Department of...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

in Support of 5 V Li-ion Chemistries Vehicle Technologies Office Merit Review 2014: Fluorinated Electrolyte for 5-V Li-Ion Chemistry High Voltage Electrolyte for Lithium Batteries...

50

High voltage dry-type air-core shunt reactors  

Science Journals Connector (OSTI)

Dry-type air-core shunt reactors are now being ... systems to limit overvoltages. Recently, high voltage dry-type air-core shunt reactors have been designed, ... transient overvoltages and electrical and magnetic...

Klaus Papp; Michael R. Sharp…

2014-11-01T23:59:59.000Z

51

High-speed low-voltage ultraviolet light source  

Science Journals Connector (OSTI)

A novel quasi-spark gap has been designed and constructed with high-speed and low-spark voltage characteristics. Ultraviolet light generating sparks can be operated at a rate of up to...

Huang, L; Hsu, S C; Kwok, H S

1984-01-01T23:59:59.000Z

52

High voltage electrical amplifier having a short rise time  

DOE Patents [OSTI]

A circuit, comprising an amplifier and a transformer is disclosed that produces a high power pulse having a fast response time, and that responds to a digital control signal applied through a digital-to-analog converter. The present invention is suitable for driving a component such as an electro-optic modulator with a voltage in the kilovolt range. The circuit is stable at high frequencies and during pulse transients, and its impedance matching circuit matches the load impedance with the output impedance. The preferred embodiment comprises an input stage compatible with high-speed semiconductor components for amplifying the voltage of the input control signal, a buffer for isolating the input stage from the output stage; and a plurality of current amplifiers connected to the buffer. Each current amplifier is connected to a field effect transistor (FET), which switches a high voltage power supply to a transformer which then provides an output terminal for driving a load. The transformer comprises a plurality of transmission lines connected to the FETs and the load. The transformer changes the impedance and voltage of the output. The preferred embodiment also comprises a low voltage power supply for biasing the FETs at or near an operational voltage.

Christie, David J. (Pleasanton, CA); Dallum, Gregory E. (Livermore, CA)

1991-01-01T23:59:59.000Z

53

Design & Fabrication of a High-Voltage Photovoltaic Cell  

SciTech Connect (OSTI)

Silicon photovoltaic (PV) cells are alternative energy sources that are important in sustainable power generation. Currently, applications of PV cells are limited by the low output voltage and somewhat low efficiency of such devices. In light of this fact, this project investigates the possibility of fabricating high-voltage PV cells on float-zone silicon wafers having output voltages ranging from 50 V to 2000 V. Three designs with different geometries of diffusion layers were simulated and compared in terms of metal coverage, recombination, built-in potential, and conduction current density. One design was then chosen and optimized to be implemented in the final device design. The results of the simulation serve as a feasibility test for the design concept and provide supportive evidence of the effectiveness of silicon PV cells as high-voltage power supplies.

Felder, Jennifer; /North Carolina State U. /SLAC

2012-09-05T23:59:59.000Z

54

High Temperature, High Voltage Fully Integrated Gate Driver Circuit  

Broader source: Energy.gov (indexed) [DOE]

driver circuit, 5-V on- chip voltage regulator, short-circuit protection, undervoltage lockout, bootstrap capacitor, dead time controller and temperature sensor * 0.8-micron,...

55

Design issues for high voltage converters for ion engines  

SciTech Connect (OSTI)

A design strategy is presented for a power converter for a high voltage ion engine for a spacecraft application. Various design issues such as appropriate topologies and control methods are considered. In this particular instance it was determined that a full bridge converter with phase shift gating and voltage mode control provided an efficient system with a minimum of electromagnetic interference. This system can be implemented in a straightforward manner, and it is relatively easy to protect from faults at the output.

King, R.J.; Stuart, T.A. [Univ. of Toledo, OH (United States)

1995-12-31T23:59:59.000Z

56

Polymerizable Additive for Passivating High Voltage Cathodes  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

batteries with the goal of significantly increasing battery energy density. Conventional Li-ion battery electrolyte systems are quite unstable at these high potentials, leading to...

57

Bi-directional power control system for voltage converter  

DOE Patents [OSTI]

A control system for a voltage converter includes: a power comparator for comparing a power signal on input terminals of the converter with a commanded power signal and producing a power comparison signal; a power regulator for transforming the power comparison signal to a commanded current signal; a current comparator for comparing the commanded current signal with a measured current signal on output terminals of the converter and producing a current comparison signal; a current regulator for transforming the current comparison signal to a pulse width modulator (PWM) duty cycle command signal; and a PWM for using the PWM duty cycle command signal to control electrical switches of the converter. The control system may further include: a command multiplier for converting a voltage signal across the output terminals of the converter to a gain signal having a value between zero (0) and unity (1), and a power multiplier for multiplying the commanded power signal by the gain signal to provide a limited commanded power signal, wherein power comparator compares the limited commanded power signal with the power signal on the input terminals.

Garrigan, Neil Richard (Niskayuna, NY); King, Robert Dean (Schenectady, NY); Schwartz, James Edward (Slingerlands, NY)

1999-01-01T23:59:59.000Z

58

Dynamic modeling and direct power control of wind turbine driven DFIG under unbalanced network voltage conditions  

Science Journals Connector (OSTI)

This paper proposes an analysis and a direct power control (DPC) design of a wind turbine driven doubly-fed induction generator (DFIG) under unbalanced network voltage conditions. A DFIG model described in the po...

Jia-bing Hu; Yi-kang He; Lie Xu

2008-12-01T23:59:59.000Z

59

E-beam high voltage switching power supply  

DOE Patents [OSTI]

A high power, solid state power supply is described for producing a controllable, constant high voltage output under varying and arcing loads suitable for powering an electron beam gun or other ion source. The present power supply is most useful for outputs in a range of about 100-400 kW or more. The power supply is comprised of a plurality of discrete switching type dc-dc converter modules, each comprising a voltage regulator, an inductor, an inverter for producing a high frequency square wave current of alternating polarity, an improved inverter voltage clamping circuit, a step up transformer, and an output rectifier for producing a dc voltage at the output of each module. The inputs to the converter modules are fed from a common dc rectifier/filter and are linked together in parallel through decoupling networks to suppress high frequency input interactions. The outputs of the converter modules are linked together in series and connected to the input of the transmission line to the load through a decoupling and line matching network. The dc-dc converter modules are phase activated such that for n modules, each module is activated equally 360{degree}/n out of phase with respect to a successive module. The phased activation of the converter modules, combined with the square current waveforms out of the step up transformers, allows the power supply to operate with greatly reduced output capacitance values which minimizes the stored energy available for discharge into an electron beam gun or the like during arcing. The present power supply also provides dynamic response to varying loads by controlling the voltage regulator duty cycle using simulated voltage feedback signals and voltage feedback loops. Circuitry is also provided for sensing incipient arc currents reflected at the output of the power supply and for simultaneously decoupling the power supply circuitry from the arcing load. 7 figs.

Shimer, D.W.; Lange, A.C.

1997-03-11T23:59:59.000Z

60

E-beam high voltage switching power supply  

DOE Patents [OSTI]

A high power, solid state power supply is described for producing a controllable, constant high voltage output under varying and arcing loads suitable for powering an electron beam gun or other ion source. The present power supply is most useful for outputs in a range of about 100-400 kW or more. The power supply is comprised of a plurality of discrete switching type dc-dc converter modules, each comprising a voltage regulator, an inductor, an inverter for producing a high frequency square wave current of alternating polarity, an improved inverter voltage clamping circuit, a step up transformer, and an output rectifier for producing a dc voltage at the output of each module. The inputs to the converter modules are fed from a common dc rectifier/filter and are linked together in parallel through decoupling networks to suppress high frequency input interactions. The outputs of the converter modules are linked together in series and connected to the input of the transmission line to the load through a decoupling and line matching network. The dc-dc converter modules are phase activated such that for n modules, each module is activated equally 360.degree./n out of phase with respect to a successive module. The phased activation of the converter modules, combined with the square current waveforms out of the step up transformers, allows the power supply to operate with greatly reduced output capacitance values which minimizes the stored energy available for discharge into an electron beam gun or the like during arcing. The present power supply also provides dynamic response to varying loads by controlling the voltage regulator duty cycle using simulated voltage feedback signals and voltage feedback loops. Circuitry is also provided for sensing incipient arc currents reflected at the output of the power supply and for simultaneously decoupling the power supply circuitry from the arcing load.

Shimer, Daniel W. (Danville, CA); Lange, Arnold C. (Livermore, CA)

1997-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage direct" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Experiment Hazard Class 13.0 - High Voltage  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

3.0 - High Voltage 3.0 - High Voltage Applicability This hazard classification applies to all experiments involving the use of High Voltage Equipment. Other hazard classifications and their associated hazard controls may also apply to experiments in this hazard class. The inspection of electric equipment is covered under the APS Policy For User Electric Equipment Inspections. NOTE: Unless required Argonne training has been completed, users are not authorized to perform electrical work. Experiment Category All Hazard Class 13 experiments are categorized as medium risk experiments. Experiment Hazard Control Verification Statements Engineered Controls - Determined by review and results of a DEEI inspection of the equipment. Procedural Controls - Determined by review and results of a DEEI

62

A Radiofrequency High-Voltage Generator  

Science Journals Connector (OSTI)

A large radio oscillator with unrectified alternating anode power-supply sends high-frequency power into a 50 meter wave-length antenna which is coiled up without insulation, and enclosed in a metal vacuum tank. Over 800,000 volts is generated inside of the tank exactly where it is to be used for x-rays or for accelerating ions. There is no insulation to become punctured. Single tuned-circuit resonance transformers are superior to coupled tuned-circuit Tesla coils. Resonance transformers, oscillator circuits, power tubes, power supply and coil construction are described. X-ray production, and ion acceleration are outlined.

David H. Sloan

1935-01-01T23:59:59.000Z

63

Self-Excited ac High Voltage Generation Using Water Droplets  

Science Journals Connector (OSTI)

By letting water drops fall through rings into cans high voltage can be spontaneously generated with no external electrical excitation. Previous work concerning this type of electric influence machine for dc and three-phase ac high voltage generation is extended to include multiphase multifrequency operation by considering N streams and N cans. A distributed equivalent circuit representation is used to calculate the natural frequencies of the system where it is found that many overstable modes are present. Experimental observations with up to five cans are presented. This device can serve as a model for phenomena concerned with atmospheric electricity.

Markus Zahn

1973-01-01T23:59:59.000Z

64

Hybrid high direct current circuit interrupter  

DOE Patents [OSTI]

A device and a method are disclosed for interrupting very high direct currents (greater than 100,000 amperes) and simultaneously blocking high voltages (greater than 600 volts). The device utilizes a mechanical switch to carry very high currents continuously with low loss and a silicon controlled rectifier (SCR) to bypass the current around the mechanical switch while its contacts are separating. A commutation circuit, connected in parallel with the SCR, turns off the SCR by utilizing a resonant circuit to divert the SCR current after the switch opens. 7 figs.

Rockot, J.H.; Mikesell, H.E.; Jha, K.N.

1998-08-11T23:59:59.000Z

65

Hybrid high direct current circuit interrupter  

DOE Patents [OSTI]

A device and a method for interrupting very high direct currents (greater than 100,000 amperes) and simultaneously blocking high voltages (greater than 600 volts). The device utilizes a mechanical switch to carry very high currents continuously with low loss and a silicon controlled rectifier (SCR) to bypass the current around the mechanical switch while its contacts are separating. A commutation circuit, connected in parallel with the SCR, turns off the SCR by utilizing a resonant circuit to divert the SCR current after the switch opens.

Rockot, Joseph H. (N. Huntingdon, PA); Mikesell, Harvey E. (McMurray, PA); Jha, Kamal N. (Bethel Park, PA)

1998-01-01T23:59:59.000Z

66

Summaries of Addresses of Presidents of Sections: High-Voltage Insulation  

Science Journals Connector (OSTI)

... subject of his presidential address to Section A (Mathematics and Physics) *'High-voltage Insulation".

1963-08-31T23:59:59.000Z

67

Current isolating epitaxial buffer layers for high voltage photodiode array  

DOE Patents [OSTI]

An array of photodiodes in series on a common semi-insulating substrate has a non-conductive buffer layer between the photodiodes and the semi-insulating substrate. The buffer layer reduces current injection leakage between the photodiodes of the array and allows optical energy to be converted to high voltage electrical energy.

Morse, Jeffrey D. (Martinez, CA); Cooper, Gregory A. (Pleasant Hill, CA)

2002-01-01T23:59:59.000Z

68

Field Optimization of Three Dimensional High Voltage C. Trinitis  

E-Print Network [OSTI]

Field Optimization of Three Dimensional High Voltage Equipment C. Trinitis Lehrstuhl f The goal of finding an optimal electric field strength distribution for arbitrary three di­ mensional­ cal optimization algorithm. The package ob­ tained from these three components is then able

Stamatakis, Alexandros

69

High voltage gas insulated transmission line with continuous particle trapping  

DOE Patents [OSTI]

This invention provides a novel high voltage gas insulated transmission line utilizing insulating supports spaced at intervals with snap-in means for supporting a continuous trapping apparatus and said trapping apparatus having perforations and cutouts to facilitate trapping of contaminating particles and system flexibility.

Cookson, Alan H. (Pittsburgh, PA); Dale, Steinar J. (Monroeville, PA)

1983-01-01T23:59:59.000Z

70

High Voltage DC Transmission 2 1.0 Introduction  

E-Print Network [OSTI]

1 High Voltage DC Transmission 2 1.0 Introduction Interconnecting HVDC within an AC system requires on use of switching devices collectively referred to in the HVDC community as valves. Valves may be non. Fig. 1 There have been three types of devices for implementing HVDC converter circuits: mercury

McCalley, James D.

71

Graz University of Technology Institute of High Voltage Engineering and System Performance  

E-Print Network [OSTI]

.hspt@tugraz.at u www.hspt.tugraz.at Institute of High Voltage Engineering and System Performance Test Laboratory systems Test of insulators, fittings and accessories Testing of high voltage equipment Impulse voltage and current tests On-site-test of medium voltage cables Electrical methods in environmental technology

72

High voltage dc--dc converter with dynamic voltage regulation and decoupling during load-generated arcs  

DOE Patents [OSTI]

A high-power power supply produces a controllable, constant high voltage output under varying and arcing loads. The power supply includes a voltage regulator, an inductor, an inverter for producing a high frequency square wave current of alternating polarity, an improved inverter voltage clamping circuit, a step up transformer, an output rectifier for producing a dc voltage at the output of each module, and a current sensor for sensing output current. The power supply also provides dynamic response to varying loads by controlling the voltage regulator duty cycle and circuitry is provided for sensing incipient arc currents at the output of the power supply to simultaneously decouple the power supply circuitry from the arcing load. The power supply includes a plurality of discrete switching type dc--dc converter modules. 5 Figs.

Shimer, D.W.; Lange, A.C.

1995-05-23T23:59:59.000Z

73

High voltage dc-dc converter with dynamic voltage regulation and decoupling during load-generated arcs  

DOE Patents [OSTI]

A high-power power supply produces a controllable, constant high voltage output under varying and arcing loads. The power supply includes a voltage regulator, an inductor, an inverter for producing a high frequency square wave current of alternating polarity, an improved inverter voltage clamping circuit, a step up transformer, an output rectifier for producing a dc voltage at the output of each module, and a current sensor for sensing output current. The power supply also provides dynamic response to varying loads by controlling the voltage regulator duty cycle and circuitry is provided for sensing incipient arc currents at the output of the power supply to simultaneously decouple the power supply circuitry from the arcing load. The power supply includes a plurality of discrete switching type dc--dc converter modules.

Shimer, Daniel W. (Danville, CA); Lange, Arnold C. (Livermore, CA)

1995-01-01T23:59:59.000Z

74

Advanced Gate Drive for the SNS High Voltage Converter Modulator  

SciTech Connect (OSTI)

SLAC National Accelerator Laboratory is developing a next generation H-bridge switch plate [1], a critical component of the SNS High Voltage Converter Modulator [2]. As part of that effort, a new IGBT gate driver has been developed. The drivers are an integral part of the switch plate, which are essential to ensuring fault-tolerant, high-performance operation of the modulator. The redesigned driver improves upon the existing gate drive in several ways. The new gate driver has improved fault detection and suppression capabilities; suppression of shoot-through and over-voltage conditions, monitoring of dI/dt and Vce(sat) for fast over-current detection and suppression, and redundant power isolation are some of the added features. In addition, triggering insertion delay is reduced by a factor of four compared to the existing driver. This paper details the design and performance of the new IGBT gate driver. A simplified schematic and description of the construction are included. The operation of the fast over-current detection circuits, active IGBT over-voltage protection circuit, shoot-through prevention circuitry, and control power isolation breakdown detection circuit are discussed.

Nguyen, M.N.; Burkhart, C.; Kemp, M.A.; /SLAC; Anderson, D.E.; /Oak Ridge

2009-05-07T23:59:59.000Z

75

High Power, High Voltage FETs in Linear Applications: A User's Perspective  

SciTech Connect (OSTI)

The specifications of the current crop of highpower, high-voltage field-effect transistors (FETs) can lure a designer into employing them in high-voltage DC equipment. Devices with extremely low on-resistance and very high power ratings are available from several manufacturers. However, our experience shows that high-voltage, linear operation of these devices at near-continuous duty can present difficult reliability challenges at stress levels well-below their published specifications. This paper chronicles the design evolution of a 600 volt, 8 ampere shunt regulator for use with megawatt-class radio transmitters, and presents a final design that has met its reliability criteria.

N. Greenough, E. Fredd, S. DePasquale

2009-09-21T23:59:59.000Z

76

Distribution System Voltage Performance Analysis for High-Penetration Photovoltaics  

SciTech Connect (OSTI)

This report examines the performance of commonly used distribution voltage regulation methods under reverse power flow.

Liu, E.; Bebic, J.

2008-02-01T23:59:59.000Z

77

Self-monitoring high voltage transmission line suspension insulator  

DOE Patents [OSTI]

A high voltage transmission line suspension insulator (18 or 22) which monitors its own dielectric integrity. A dielectric rod (10) has one larger diameter end fitting attachable to a transmission line and another larger diameter end fitting attachable to a support tower. The rod is enclosed in a dielectric tube (14) which is hermetically sealed to the rod's end fittings such that a liquidtight space (20) is formed between the rod and the tube. A pressurized dielectric liquid is placed within that space. A discoloring dye placed within this space is used to detect the loss of the pressurized liquid.

Stemler, Gary E. (Vancouver, WA); Scott, Donald N. (Vancouver, WA)

1981-01-01T23:59:59.000Z

78

An Approximate Dynamic Programming Algorithm for the Allocation of High-Voltage Transformer Spares in the  

E-Print Network [OSTI]

An Approximate Dynamic Programming Algorithm for the Allocation of High-Voltage Transformer Spares high-voltage transformer spares throughout the electric grid to mitigate the risk of random transformer-voltage transformers are an integral part of the electric transmission system. A catas- trophic transformer failure

Powell, Warren B.

79

Seismic vulnerability assessment of a high voltage disconnect switch  

Science Journals Connector (OSTI)

Abstract This paper deals with the seismic vulnerability of high voltage equipment typically installed in electric substations. In particular, the seismic response of a 380 kV vertical disconnect switch has been investigated based on the results of an experimental campaign carried out at Roma Tre University. According to a series of non-linear analyses, the influence of the most significant parameters on the seismic behavior of this apparatus has been analyzed and the corresponding fragility curves have been evaluated by using the Effective Fragility Analysis method. The results showed a limited vulnerability of the disconnect switch, whose most critical parts are the bottom joint of the ceramic support column and the steel column base.

Fabrizio Paolacci; Renato Giannini; Silvia Alessandri; Gianmarco De Felice

2014-01-01T23:59:59.000Z

80

Voltage spike detection in high field superconducting accelerator magnets  

SciTech Connect (OSTI)

A measurement system for the detection of small magnetic flux changes in superconducting magnets, which are due to either mechanical motion of the conductor or flux jump, has been developed at Fermilab. These flux changes are detected as small amplitude, short duration voltage spikes, which are {approx}15mV in magnitude and lasts for {approx}30 {micro}sec. The detection system combines an analog circuit for the signal conditioning of two coil segments and a fast data acquisition system for digitizing the results, performing threshold detection, and storing the resultant data. The design of the spike detection system along with the modeling results and noise analysis will be presented. Data from tests of high field Nb{sub 3}Sn magnets at currents up to {approx}20KA will also be shown.

Orris, D.F.; Carcagno, R.; Feher, S.; Makulski, A.; Pischalnikov, Y.M.; /Fermilab

2004-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage direct" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Monolithic high voltage nonlinear transmission line fabrication process  

DOE Patents [OSTI]

A process for fabricating sequential inductors and varistor diodes of a monolithic, high voltage, nonlinear, transmission line in GaAs is disclosed. An epitaxially grown laminate is produced by applying a low doped active n-type GaAs layer to an n-plus type GaAs substrate. A heavily doped p-type GaAs layer is applied to the active n-type layer and a heavily doped n-type GaAs layer is applied to the p-type layer. Ohmic contacts are applied to the heavily doped n-type layer where diodes are desired. Multiple layers are then either etched away or Oxygen ion implanted to isolate individual varistor diodes. An insulator is applied between the diodes and a conductive/inductive layer is thereafter applied on top of the insulator layer to complete the process. 6 figs.

Cooper, G.A.

1994-10-04T23:59:59.000Z

82

High-speed, sub-pull-in voltage MEMS switching.  

SciTech Connect (OSTI)

We have proposed and demonstrated MEMS switching devices that take advantage of the dynamic behavior of the MEMS devices to provide lower voltage actuation and higher switching speeds. We have explored the theory behind these switching techniques and have demonstrated these techniques in a range of devices including MEMS micromirror devices and in-plane parallel plate MEMS switches. In both devices we have demonstrated switching speeds under one microsecond which has essentially been a firm limit in MEMS switching. We also developed low-loss silicon waveguide technology and the ability to incorporate high-permittivity dielectric materials with MEMS. The successful development of these technologies have generated a number of new projects and have increased both the MEMS switching and optics capabilities of Sandia National Laboratories.

Spahn, Olga Blum; Brewer, Steven; Olsson, Roy H.; Bogart, Gregory R.; Luck, David L.; Watts, Michael R.; Shaw, Michael J.; Nielson, Gregory N.; Resnick, Paul James; Tigges, Christopher P.; Grossetete, Grant David

2008-01-01T23:59:59.000Z

83

Monolithic high voltage nonlinear transmission line fabrication process  

DOE Patents [OSTI]

A process for fabricating sequential inductors and varactor diodes of a monolithic, high voltage, nonlinear, transmission line in GaAs is disclosed. An epitaxially grown laminate is produced by applying a low doped active n-type GaAs layer to an n-plus type GaAs substrate. A heavily doped p-type GaAs layer is applied to the active n-type layer and a heavily doped n-type GaAs layer is applied to the p-type layer. Ohmic contacts are applied to the heavily doped n-type layer where diodes are desired. Multiple layers are then either etched away or Oxygen ion implanted to isolate individual varactor diodes. An insulator is applied between the diodes and a conductive/inductive layer is thereafter applied on top of the insulator layer to complete the process.

Cooper, Gregory A. (346 Primrose Dr., Pleasant Hill, CA 94523)

1994-01-01T23:59:59.000Z

84

High-voltage supply for neutron tubes in well-logging applications  

DOE Patents [OSTI]

A high voltage supply is provided for a neutron tube used in well logging. The biased pulse supply of the invention combines DC and full pulse techniques and produces a target voltage comprising a substantial negative DC bias component on which is superimposed a pulse whose negative peak provides the desired negative voltage level for the neutron tube. The target voltage is preferably generated using voltage doubling techniques and employing a voltage source which generates bipolar pulse pairs having an amplitude corresponding to the DC bias level.

Humphreys, D.R.

1982-09-15T23:59:59.000Z

85

Current-based direct power control of a DFIG under unbalanced grid voltage  

Science Journals Connector (OSTI)

Abstract A novel current-based direct power control (CB-DPC) strategy for a grid-connected doubly-fed induction generator (DFIG) is proposed. The reported control scheme is applicable to DFIG-based variable-speed wind turbines that operate under unbalanced network voltages. The required DFIG rotor voltage for precise regulation of the stator active and reactive output powers and accurate elimination of their inherent pulsations are directly obtained using a nonlinear integral sliding-mode control (ISMC) scheme. Compared with other control methods, the proposed strategy is simpler since it is not based on the symmetrical components theory, does not need multiple synchronous coordinate transformations, and only requires DFIG voltage and current values as its inputs. Constant switching frequency of the rotor-side converter (RSC) is achieved by means of space vector pulse-width modulation (SVPWM) technique. Uncertainties in the parameters of the generator are included in the design. A compensation strategy is also proposed for tracking error mitigation of the powers that occur due to elimination of the chattering phenomena in the ISMC scheme. Simulation results on a 2MW DFIG under different operating conditions are presented to validate the effectiveness and robustness of the proposed method.

Mohammad Farshadnia; Seyed Abbas Taher

2014-01-01T23:59:59.000Z

86

Performance Analysis of a Hybrid Asymmetric Multilevel Inverter for High Voltage Active Power Filter Applications  

E-Print Network [OSTI]

Performance Analysis of a Hybrid Asymmetric Multilevel Inverter for High Voltage Active Power voltage-source inverters connected in series (known as cascaded hybrid asymmetric multilevel inverter voltage application due to semiconductor constraint. In order to achieve higher power level, hybrid

Catholic University of Chile (Universidad Católica de Chile)

87

Radio-Frequency Interference (RFI) From Extra-High-Voltage (EHV) Transmission Lines  

E-Print Network [OSTI]

discharges are a design issue. Extra-high-voltage (EHV) transmission lines have operating voltages of 345 kV building a 345-kV transmission line from Red Hill, NM to Deming, NM which would run east along US60 to its with respect to radio noise: (1) lines with voltages below 70 kV and (2) lines with voltages above 110 kV

Ellingson, Steven W.

88

3D MHD modelling of the glidarc behaviour of a low current high voltage DC plasma torch Journal of Physics D: Applied Physics  

E-Print Network [OSTI]

in terms of: global behaviour, arc length, mean voltage and glidarc frequency. 1. Introduction The non-thermal on magnetohydrodynamic (MHD) modelling of atmospheric pressure direct current (DC) plasma torch operating at low current3D MHD modelling of the glidarc behaviour of a low current ­ high voltage DC plasma torch Journal

Paris-Sud XI, Université de

89

High voltage power supply with modular series resonant inverters  

DOE Patents [OSTI]

A relatively small and compact high voltage, high current power supply for a laser utilizes a plurality of modules containing series resonant half bridge inverters. A pair of reverse conducting thyristors are incorporated in each series resonant inverter module such that the series resonant inverter modules are sequentially activated in phases 360.degree./n apart, where n=number of modules for n>2. Selective activation of the modules allows precise output control reducing ripple and improving efficiency. Each series resonant half bridge inverter module includes a transformer which has a cooling manifold for actively circulating a coolant such as water, to cool the transformer core as well as selected circuit elements. Conductors connecting and forming various circuit components comprise hollow, electrically conductive tubes such as copper. Coolant circulates through the tubes to remove heat. The conductive tubes act as electrically conductive lines for connecting various components of the power supply. Where it is desired to make electrical isolation breaks, tubes comprised of insulating material such as nylon are used to provide insulation and continue the fluid circuit.

Dreifuerst, Gary R. (Livermore, CA); Merritt, Bernard T. (Livermore, CA)

1995-01-01T23:59:59.000Z

90

High voltage power supply with modular series resonant inverters  

DOE Patents [OSTI]

A relatively small and compact high voltage, high current power supply for a laser utilizes a plurality of modules containing series resonant half bridge inverters. A pair of reverse conducting thyristors are incorporated in each series resonant inverter module such that the series resonant inverter modules are sequentially activated in phases 360{degree}/n apart, where n=number of modules for n>2. Selective activation of the modules allows precise output control reducing ripple and improving efficiency. Each series resonant half bridge inverter module includes a transformer which has a cooling manifold for actively circulating a coolant such as water, to cool the transformer core as well as selected circuit elements. Conductors connecting and forming various circuit components comprise hollow, electrically conductive tubes such as copper. Coolant circulates through the tubes to remove heat. The conductive tubes act as electrically conductive lines for connecting various components of the power supply. Where it is desired to make electrical isolation breaks, tubes comprised of insulating material such as nylon are used to provide insulation and continue the fluid circuit. 11 figs.

Dreifuerst, G.R.; Merritt, B.T.

1995-07-18T23:59:59.000Z

91

Object Oriented Safety Analysis of an Extra High Voltage Substation Bay  

Science Journals Connector (OSTI)

Experiences of application of the object oriented approach to safety analysis of an extra high voltage substation bay are presented. As the first step...

Bartosz Nowicki; Janusz Górski

1998-01-01T23:59:59.000Z

92

Theory and practice of dynamic voltage/frequency scaling in the high performance computing environment.  

E-Print Network [OSTI]

?? This dissertation provides a comprehensive overview of the theory and practice of Dynamic Voltage/Frequency Scaling (DVFS) in the High Performance Computing (HPC) environment. We… (more)

Rountree, Barry Louis

2010-01-01T23:59:59.000Z

93

Automotive high-voltage electrical system with integrated safeguard  

Science Journals Connector (OSTI)

For several years the use of higher system voltages has been a topic in the automotive industry. Whether for hybrid or conventional vehicles, safeguards are required which protect both the vehicle...

Thomas Flottmann

2007-03-01T23:59:59.000Z

94

Chapter 19. High Voltage Insulation, Diagnostics and Energetic Electron and Photon Beam Interactions  

E-Print Network [OSTI]

Chapter 19. High Voltage Insulation, Diagnostics and Energetic Electron and Photon Beam Interactions 19-1 High Voltage Insulation, Diagnostics and Energetic Electron and Photon Beam Interactions 1. DC Properties of Modern Filled Epoxy Insulation Academic and Research Staff Dr. Chathan Cooke Sponsor

95

Evaluation of Insulation Systems for the Optimal Design of High Voltage Pulse Transformers  

E-Print Network [OSTI]

This paper presents a study for the design of the insulation systems of high voltage pulse transformer based on experimental tests and numerical simulations. Data of high voltage tests on solid and liquid insulation materials are presented and discussed. The understanding of each part of the insulation is supported by electrostatic fields simulations.

Sylvain, Candolfi; Davide, Aguglia; Philippe, Viarouge; Jürgen, Biela; Jerome, Cros

2015-01-01T23:59:59.000Z

96

High-voltage direct current handbook: First edition  

SciTech Connect (OSTI)

HVDC systems offer opportunities for power transfer between asynchronous systems, improved performance of the ac system in which the dc link is integrated, and possibly increased power transfer across existing lines if converted to HVDC. This handbook is intended to help planners and engineers understand the intricacies of HVDC systems.

Piwko, R.J.; Leonard, D.J.; Nolan, J.J.; Thorpe, J.B. [eds.] [GE Industrial and Power Systems, Schenectady, NY (United States)

1994-12-31T23:59:59.000Z

97

High-Voltage Broadband-Over-Powerline (HV-BPL) Field Test Report | Open  

Open Energy Info (EERE)

High-Voltage Broadband-Over-Powerline (HV-BPL) Field Test Report High-Voltage Broadband-Over-Powerline (HV-BPL) Field Test Report Jump to: navigation, search Tool Summary LAUNCH TOOL Name: High-Voltage Broadband-Over-Powerline (HV-BPL) Field Test Report Focus Area: Crosscutting Topics: Policy Impacts Website: www.netl.doe.gov/smartgrid/referenceshelf/reports/HV-BPL_Final_Report. Equivalent URI: cleanenergysolutions.org/content/high-voltage-broadband-over-powerline Language: English Policies: "Deployment Programs,Financial Incentives" is not in the list of possible values (Deployment Programs, Financial Incentives, Regulations) for this property. DeploymentPrograms: Technical Assistance This reports details findings from a pilot High Voltage Broadband over Power Line (HV-BPL) program, an effort to develop a disruptive technology

98

Application-Directed Voltage Scaling Johan Pouwelse, Koen Langendoen, and Henk Sips  

E-Print Network [OSTI]

--Clock (and voltage) scheduling is an important tech- nique to reduce the energy consumption of processors that sup- port voltage scaling. It is difficult, however, to achieve good re- sults using only statistics to the scheduler control- ling the clock speed and processor voltage. This paper describes our Energy Priority

Pouwelse, Johan

99

Design of the Wireless Temperature Measurement Alarming System in the High-Voltage Transformer Substation  

Science Journals Connector (OSTI)

Due to electric power overload and equipment aging, fire and explosion occur at transmission circuitry joints in high-voltage transformer substation caused by high temperatures accumulated at these...

Qiang Gao; Hongli Wang; Huaxiang Wang

2008-01-01T23:59:59.000Z

100

The high voltage problem in the saturated core HTS fault current limiter  

Science Journals Connector (OSTI)

A small model of a one-phase saturated core HTS fault current limiter was developed. It consists of an iron core, an AC coil and a DC HTS coil. The HTS coil comprised six 126 turns double-pancakes (ID 70 mm), wound after heat treatment from Bi-2223 multifilamentary tape in Ag matrix. A fault simulation circuit was set up to characterize the dynamic properties of the model limiter. The voltages and currents of the AC coil and the DC HTS coil were measured through a computer-based data acquisition system. The tests have shown that the limiter has a fast response and the first current peak can be easily limited, but a high voltage will be induced on the DC HTS coil side during the fault state. This high voltage can badly affect the DC current equipment on the DC HTS coil side. The origin and value of the high voltage can be explained using a transformer model. For a limiter with n1 turns AC coil and n2 turns DC coil, the largest induced voltage will be roughly close to (n2/n1)U, where U is the rated voltage of the limiter. To commercialize this kind of limiter, the high voltage problem must be solved. Some different designs were introduced to lower the induced voltage.

Y.F. He; J.H. Li; X.H. Zong; J. Sun; Y.N. Wang; C.L. Wu; J.X. Wang

2003-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage direct" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Public Opinions of Building Additional High-Voltage Electric Power Lines  

E-Print Network [OSTI]

to build new power lines. Residents living in counties with planned routes for new transmission linesPublic Opinions of Building Additional High-Voltage Electric Power Lines A Report to the National-Voltage Electric Power Lines: A Report to the National Science Foundation and the Electric Power Research Center

Tesfatsion, Leigh

102

Light-weight DC to very high voltage DC converter  

DOE Patents [OSTI]

A DC-DC converter capable of generating outputs of 100 KV without a transformer comprises a silicon opening switch (SOS) diode connected to allow a charging current from a capacitor to flow into an inductor. When a specified amount of charge has flowed through the SOS diode, it opens up abruptly; and the consequential collapsing field of the inductor causes a voltage and current reversal that is steered into a load capacitor by an output diode. A switch across the series combination of the capacitor, inductor, and SOS diode closes to periodically reset the SOS diode by inducing a forward-biased current.

Druce, Robert L. (Union City, CA); Kirbie, Hugh C. (Dublin, CA); Newton, Mark A. (Livermore, CA)

1998-01-01T23:59:59.000Z

103

Light-weight DC to very high voltage DC converter  

DOE Patents [OSTI]

A DC-DC converter capable of generating outputs of 100 KV without a transformer comprises a silicon opening switch (SOS) diode connected to allow a charging current from a capacitor to flow into an inductor. When a specified amount of charge has flowed through the SOS diode, it opens up abruptly; and the consequential collapsing field of the inductor causes a voltage and current reversal that is steered into a load capacitor by an output diode. A switch across the series combination of the capacitor, inductor, and SOS diode closes to periodically reset the SOS diode by inducing a forward-biased current. 1 fig.

Druce, R.L.; Kirbie, H.C.; Newton, M.A.

1998-06-30T23:59:59.000Z

104

Utility-Scale Solar Power Converter: Agile Direct Grid Connect Medium Voltage 4.7-13.8 kV Power Converter for PV Applications Utilizing Wide Band Gap Devices  

SciTech Connect (OSTI)

Solar ADEPT Project: Satcon is developing a compact, lightweight power conversion device that is capable of taking utility-scale solar power and outputting it directly into the electric utility grid at distribution voltage levels—eliminating the need for large transformers. Transformers “step up” the voltage of the power that is generated by a solar power system so it can be efficiently transported through transmission lines and eventually “stepped down” to usable voltages before it enters homes and businesses. Power companies step up the voltage because less electricity is lost along transmission lines when the voltage is high and current is low. Satcon’s new power conversion devices will eliminate these heavy transformers and connect a utility-scale solar power system directly to the grid. Satcon’s modular devices are designed to ensure reliability—if one device fails it can be bypassed and the system can continue to run.

None

2012-01-25T23:59:59.000Z

105

Princeton Power Systems (TRL 5 6 Component)- Marine High-Voltage Power Conditioning and Transmission System with Integrated Energy Storage  

Broader source: Energy.gov [DOE]

Princeton Power Systems (TRL 5 6 Component) - Marine High-Voltage Power Conditioning and Transmission System with Integrated Energy Storage

106

Generalized charge simulation method for the calculation of the electric field in high voltage substations  

Science Journals Connector (OSTI)

This paper deals with the calculation of the electric field strength in high voltage (HV) substations comprising complex geometrical structures. Generalized charge simulation ... is to examine the influence of to...

Aleksandar Rankovi?; Milan S. Savi?

2010-07-01T23:59:59.000Z

107

Vehicle Technologies Office Merit Review 2014: High-Voltage Solid Polymer Batteries for Electric Drive Vehicles  

Broader source: Energy.gov [DOE]

Presentation given by Seeo, Inc. at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about high-voltage solid polymer...

108

Optical High Voltage Sensor with Oil- and Gas-free Insulation  

Science Journals Connector (OSTI)

We present an electro-optic high voltage sensor with novel oil- and gas-free insulation based on capacitive electric field steering. The sensor's accuracy is within ±0.2% in a...

Marchese, Sergio V; Wildermuth, Stephan; Steiger, Olivier; Pascal, Joris; Bohnert, Klaus; Eriksson, Göran; Czyzewski, Jan

109

Current mode integrators and their applications in low-voltage high frequency CMOS signal processing  

E-Print Network [OSTI]

Low voltage CMOS fully differential integrators for high frequency continuous-time filters using current-mode techniques are presented.. Current mode techniques are employed to avoid the use of the floating differential pair, in order to achieve...

Smith, Sterling Lane

2012-06-07T23:59:59.000Z

110

Low Cost SiOx-Graphite and High Voltage Spinel Cathode | Department...  

Office of Environmental Management (EM)

Cathode Low Cost SiOx-Graphite and High Voltage Spinel Cathode 2011 DOE Hydrogen and Fuel Cells Program, and Vehicle Technologies Program Annual Merit Review and Peer Evaluation...

111

High-voltage pulsed discharge in an electron source with a plasma cathode  

Science Journals Connector (OSTI)

The nature of and mechanism for producing a high-voltage discharge in an electron source with a plasma cathode are investigated. The possibility of generating pulsed electron currents with an amplitude of 103–104

S. P. Bugaev; F. Ya. Zagulov

1973-10-01T23:59:59.000Z

112

Modeling and improvement of direct power control of DFIG under unbalanced grid voltage condition  

Science Journals Connector (OSTI)

Abstract This paper presents analysis and control of a doubly-fed induction generator (DFIG)-based wind generation system operating under unbalanced grid voltage condition. The DFIG system is modeled in synchronous positive reference frame. System behavior and operation of both the generator and the grid side converter (GSC) under unbalanced condition is illustrated by definition of oscillating power terms in the synchronous reference frame. This analysis makes it possible to control both the active and reactive power generation by means of direct power control (DPC) technique. It is shown that considering the DFIG model in synchronous reference frame simplifies the power terms extraction. Moreover, alternative DFIG control targets such as reducing unbalanced stator current, torque and power pulsations minimization, are considered. In addition, by the proposed method, the oscillation of the stator output power is compensated by the GSC, to ensure constant power output from the overall DFIG generation system. The validation of results has been performed through simulation results on a 2 MW DFIG wind generation system.

Mohammad Jafar Zandzadeh; Abolfazl Vahedi

2014-01-01T23:59:59.000Z

113

Cermet insert high voltage holdoff improvement for ceramic/metal vacuum devices  

DOE Patents [OSTI]

An improved metal-to-ceramic seal is provided wherein the ceramic body of the seal contains an integral region of cermet material in electrical contact with the metallic member, e.g., an electrode, of the seal. The seal is useful in high voltage vacuum devices, e.g., vacuum switches, and increases the high-voltage holdoff capabilities of such devices. A method of fabricating such seals is also provided.

Ierna, W.F.

1986-03-11T23:59:59.000Z

114

Direct Power Control of Doubly-Fed Generator Based Wind Turbine Converters to Improve Low Voltage  

E-Print Network [OSTI]

Control (DPC) is discussed for Low Voltage Ride Through (LVRT) of DFIG based wind turbine converters power integration state that doubly fed induction generator (DFIG) controllers should be capable and maintaining dc bus voltage, then the DFIG will stay online during the disturbance. A fast acting controller

Kimball, Jonathan W.

115

Voltage-dependent calcium channels and currents in native neurons and other cells have been divided into high voltage  

E-Print Network [OSTI]

Voltage-dependent calcium channels and currents in native neurons and other cells have been divided than one subtype of channel. A new subfamily of voltage-dependent calcium channel á1 subunit genes. 1999), having four domains, each with a voltage sensor and a pore-forming P loop. However

Dolphin, Annette C.

116

Distributed Voltage and Current Control of Multi-Terminal High-Voltage Direct  

E-Print Network [OSTI]

to AC transmission systems. Off-shore wind farms also typically require HVDC power transmission This work was supported in part by the European Commission by the Hycon2 project, the Swedish Research

Dimarogonas, Dimos

117

High Voltage Testing of a 5-meter Prototype Triaxial HTS Cable  

SciTech Connect (OSTI)

High voltage tests were performed on a 5-m long prototype triaxial HTS cable (supplied by Ultera) at ORNL in preparation for installation of a 200-m HTS cable of the same design at the AEP utility substation in Columbus, Ohio. The triaxial design comprises three concentric phases and shield around a common former with the phase to phase dielectric at cryogenic temperature. Advantages of this design include increased current density, a reduced amount of HTS tape needed, and reduced heat load. The phase to phase voltage will be 13.2 kVrms (7.6 kVrms to ground). Preliminary testing was done on half-scale and full-scale terminations which successfully passed AC withstand, partial discharge, and impulse tests. High voltage tests conducted on the 5-m cable with the cable straight and after bending 90 degrees were ac withstand to 39 kVrms, partial discharge inception, and a minimum of 10 positive and 10 negative lightning waveform impulses at 110 kV. Phase to phase insulation was tested by applying high voltage to each phase one at a time with all the other phases grounded. Partial discharge data will be presented. The 5-m prototype triaxial HTS cable passed all the HV tests performed, with a PD inception voltage significantly above the required voltage.

Sauers, Isidor [ORNL; James, David Randy [ORNL; Ellis, Alvin R [ORNL; Tuncer, Enis [ORNL; Pace, Marshall O [ORNL; Gouge, Michael J [ORNL; Demko, Jonathan A [ORNL; Lindsay, David T [ORNL

2007-01-01T23:59:59.000Z

118

Mechanisms of deflagration-to-detonation transition under initiation by high-voltage nanosecond discharges  

SciTech Connect (OSTI)

An experimental study of detonation initiation in a stoichiometric propane-oxygen mixture by a high-voltage nanosecond gas discharge was performed in a detonation tube with a single-cell discharge chamber. The discharge study performed in this geometry showed that three modes of discharge development were realized under the experimental conditions: a spark mode with high-temperature channel formation, a streamer mode with nonuniform gas excitation, and a transient mode. Under spark and transient initiation, simultaneous ignition inside the discharge channel occurred, forming a shock wave and leading to a conventional deflagration-to-detonation transition (DDT) via an adiabatic explosion. The DDT length and time at 1 bar of initial pressure in the square smooth tube with a 20-mm transverse size amounted to 50 mm and 50{mu}s, respectively. The streamer mode of discharge development at an initial pressure of 1 bar resulted in nonuniform mixture excitation and a successful DDT via a gradient mechanism, which was confirmed by high-speed time resolved ICCD imaging. The gradient mechanism implied a longer DDT time of 150{mu}s, a DDT run-up distance of 50 mm, and an initiation energy of 1 J, which is two orders of magnitude less than the direct initiation energy for a planar detonation under these conditions. (author)

Rakitin, Aleksandr E.; Starikovskii, Andrei Yu. [Physics of Nonequilibrium Systems Lab, Moscow Institute of Physics and Technology, 9 Institutski Lane, Dolgoprudny 141700 (Russian Federation)

2008-10-15T23:59:59.000Z

119

The design, construction, and operation of long-distance high-voltage electricity transmission technologies.  

SciTech Connect (OSTI)

This report focuses on transmission lines, which operate at voltages of 115 kV and higher. Currently, the highest voltage lines comprising the North American power grid are at 765 kV. The grid is the network of transmission lines that interconnect most large power plants on the North American continent. One transmission line at this high voltage was built near Chicago as part of the interconnection for three large nuclear power plants southwest of the city. Lines at this voltage also serve markets in New York and New England, also very high demand regions. The large power transfers along the West Coast are generally at 230 or 500 kV. Just as there are practical limits to centralization of power production, there are practical limits to increasing line voltage. As voltage increases, the height of the supporting towers, the size of the insulators, the distance between conductors on a tower, and even the width of the right-of-way (ROW) required increase. These design features safely isolate the electric power, which has an increasing tendency to arc to ground as the voltage (or electrical potential) increases. In addition, very high voltages (345 kV and above) are subject to corona losses. These losses are a result of ionization of the atmosphere, and can amount to several megawatts of wasted power. Furthermore, they are a local nuisance to radio transmission and can produce a noticeable hum. Centralized power production has advantages of economies of scale and special resource availability (for instance, hydro resources), but centralized power requires long-distance transfers of power both to reach customers and to provide interconnections for reliability. Long distances are most economically served at high voltages, which require large-scale equipment and impose a substantial footprint on the corridors through which power passes. The most visible components of the transmission system are the conductors that provide paths for the power and the towers that keep these conductors at a safe distance from each other and from the ground and the natural and built environment. Common elements that are generally less visible (or at least more easily overlooked) include the maintained ROW along the path of the towers, access roads needed for maintenance, and staging areas used for initial construction that may be restored after construction is complete. Also visible but less common elements along the corridor may include switching stations or substations, where lines of similar or different voltages meet to transfer power.

Molburg, J. C.; Kavicky, J. A.; Picel, K. C.

2008-03-03T23:59:59.000Z

120

A high-gain adaptive observer for detecting Li-ion battery terminal voltage collapse  

Science Journals Connector (OSTI)

We use a high-gain adaptive observer and a trend filtering algorithm to detect early stages that lead to terminal voltage collapses in Li-ion batteries. This approach allows accurate detection without having sophisticated battery models. Theoretical ... Keywords: Adaptive filters, Adaptive systems, Detection algorithms, High-gain, Trend

Shayok Mukhopadhyay, Fumin Zhang

2014-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage direct" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Experimental evaluation of actual delivered dose using mega-voltage cone-beam CT and direct point dose measurement  

SciTech Connect (OSTI)

Radiation therapy in patients is planned by using computed tomography (CT) images acquired before start of the treatment course. Here, tumor shrinkage or weight loss or both, which are common during the treatment course for patients with head-and-neck (H and N) cancer, causes unexpected differences from the plan, as well as dose uncertainty with the daily positional error of patients. For accurate clinical evaluation, it is essential to identify these anatomical changes and daily positional errors, as well as consequent dosimetric changes. To evaluate the actual delivered dose, the authors proposed direct dose measurement and dose calculation with mega-voltage cone-beam CT (MVCBCT). The purpose of the present study was to experimentally evaluate dose calculation by MVCBCT. Furthermore, actual delivered dose was evaluated directly with accurate phantom setup. Because MVCBCT has CT-number variation, even when the analyzed object has a uniform density, a specific and simple CT-number correction method was developed and applied for the H and N site of a RANDO phantom. Dose distributions were calculated with the corrected MVCBCT images of a cylindrical polymethyl methacrylate phantom. Treatment processes from planning to beam delivery were performed for the H and N site of the RANDO phantom. The image-guided radiation therapy procedure was utilized for the phantom setup to improve measurement reliability. The calculated dose in the RANDO phantom was compared to the measured dose obtained by metal-oxide-semiconductor field-effect transistor detectors. In the polymethyl methacrylate phantom, the calculated and measured doses agreed within about +3%. In the RANDO phantom, the dose difference was less than +5%. The calculated dose based on simulation-CT agreed with the measured dose within±3%, even in the region with a high dose gradient. The actual delivered dose was successfully determined by dose calculation with MVCBCT, and the point dose measurement with the image-guided radiation therapy procedure.

Matsubara, Kana, E-mail: matsubara-kana@hs.tmu.ac.jp [Graduate School of Human Health Sciences, Tokyo Metropolitan University, Arakawa-ku Tokyo (Japan); Kohno, Ryosuke [National Cancer Center Hospital East, Chiba (Japan); National Cancer Center Research Institute, Chiba (Japan); Nishioka, Shie; Shibuya, Toshiyuki; Ariji, Takaki; Akimoto, Tetsuo [National Cancer Center Hospital East, Chiba (Japan); Saitoh, Hidetoshi [Graduate School of Human Health Sciences, Tokyo Metropolitan University, Arakawa-ku Tokyo (Japan)

2013-07-01T23:59:59.000Z

122

Dual design resistor for high voltage conditioning and transmission lines  

DOE Patents [OSTI]

A dual resistor for eliminating the requirement for two different value resistors. The dual resistor includes a conditioning resistor at a high resistance value and a run resistor at a low resistance value. The run resistor can travel inside the conditioning resistor. The run resistor is capable of being advanced by a drive assembly until an electrical path is completed through the run resistor thereby shorting out the conditioning resistor and allowing the lower resistance run resistor to take over as the current carrier.

Siggins, Timothy Lynn (Newport News, VA); Murray, Charles W. (Hayes, VA); Walker, Richard L. (Norfolk, VA)

2007-01-23T23:59:59.000Z

123

Optimizing performance per watt on GPUs in High Performance Computing: temperature, frequency and voltage effects  

E-Print Network [OSTI]

The magnitude of the real-time digital signal processing challenge attached to large radio astronomical antenna arrays motivates use of high performance computing (HPC) systems. The need for high power efficiency (performance per watt) at remote observatory sites parallels that in HPC broadly, where efficiency is an emerging critical metric. We investigate how the performance per watt of graphics processing units (GPUs) is affected by temperature, core clock frequency and voltage. Our results highlight how the underlying physical processes that govern transistor operation affect power efficiency. In particular, we show experimentally that GPU power consumption grows non-linearly with both temperature and supply voltage, as predicted by physical transistor models. We show lowering GPU supply voltage and increasing clock frequency while maintaining a low die temperature increases the power efficiency of an NVIDIA K20 GPU by up to 37-48% over default settings when running xGPU, a compute-bound code used in radio...

Price, D C; Barsdell, B R; Babich, R; Greenhill, L J

2014-01-01T23:59:59.000Z

124

International Symposium on High Voltage Engineering, London, August 1999 page 1 of 4  

E-Print Network [OSTI]

substations (GIS) are described. Calculated transfer functions are presented, showing that transverse electric) in gas insulated substations (GIS) has been described in detail previously [1]. In this paper, we present that occurs somewhere in the insulating region between the high voltage (HV) conductor and the metal cladding

Judd, Martin

125

Study of the electric field generated by the high voltage substations  

Science Journals Connector (OSTI)

The paper outlines the results of a study regarding the electromagnetic field generated by a 400 kV high voltage (HV) substation belonging to the Romanian national Power Grid Company Transelectrica SA. In the first part of the paper, a semi-analytical ... Keywords: HV substations, computation, electromagnetic field, human exposure, limits

Calin Munteanu; Vasile Topa; Marius Purcar; Laura Grindei; Adina Racasan

2010-10-01T23:59:59.000Z

126

Geomagnetically induced currents in the Uruguayan high-voltage power grid  

Science Journals Connector (OSTI)

......currents in the Uruguayan high-voltage power grid R. Caraballo 1 2 L. Sanchez Bettucci...simple topology of the Uruguayan power grid provides some advantages in the calculation...transformers at the South African power grid during the Halloween storm in 2003......

R. Caraballo; L. Sánchez Bettucci; G. Tancredi

2013-01-01T23:59:59.000Z

127

Electro-optic imagery of high-voltage GaAs photoconductive switches  

SciTech Connect (OSTI)

The authors present electro-optic images of GaAs high-voltage photoconductive switches utilizing the electro-optic effect of the semi-insulating GaAs substrate. Experimental methodology for obtaining the images is described along with a self-calibrating data reduction algorithm. Use of the technique for observing fabrication defects is shown.

Falk, R.A.; Adams, J.C.; Capps, C.D.; Ferrier, S.G.; Krinsky, J.A. (Boeing Defense and Space Group, Seattle, WA (United States))

1995-01-01T23:59:59.000Z

128

An earth-isolated optically coupled wideband high voltage probe powered by ambient light  

E-Print Network [OSTI]

(2012) Optimized working conditions for a thermoelectric generator as a topping cycle for gas turbines J (2012) Feasibility study in application of forging waste heat on absorption cooling system J. Renewable-emitting diode that converts high voltage into an amplitude-modulated optical signal, which is then conveyed

Bellan, Paul M.

129

Effect of high solenoidal magnetic fields on breakdown voltages of high vacuum 805 MHz cavities  

SciTech Connect (OSTI)

There is an on going international collaboration studying the feasibility and cost of building a muon collider or neutrino factory [1,2]. An important aspect of this study is the full understanding of ionization cooling of muons by many orders of magnitude for the collider case. An important muon ionization cooling experiment, MICE [3], has been proposed to demonstrate and validate the technology that could be used for cooling. Ionization cooling is accomplished by passing a high-emittance muon beam alternately through regions of low Z material, such as liquid hydrogen, and very high accelerating RF Cavities within a multi-Tesla solenoidal field. To determine the effect of very large solenoidal magnetic fields on the generation of dark current, x-rays and on the breakdown voltage gradients of vacuum RF cavities, a test facility has been established at Fermilab in Lab G. This facility consists of a 12 MW 805 MHz RF station and a large warm bore 5 T solenoidal superconducting magnet containing a pill box type cavity with thin removable window apertures. This system allows dark current and breakdown studies of different window configurations and materials. The results of this study will be presented. The study has shown that the peak achievable accelerating gradient is reduced by a factor greater than 2 when solenoidal field of greater than 2 T are applied to the cavity.

Moretti, A.; Bross, A.; Geer, S.; Qian, Z.; /Fermilab; Norem, J.; /Argonne; Li, D.; Zisman, M.; /LBL, Berkeley; Torun, Y.; /IIT, Chicago; Rimmer, R.; /Jefferson Lab; Errede,; /Illinois U., Urbana

2005-10-01T23:59:59.000Z

130

Breaking the ice: de-icing power transmission lines with high-frequency, high-voltage excitation  

E-Print Network [OSTI]

Breaking the ice: de-icing power transmission lines with high-frequency, high-voltage excitation of this work in other works must be obtained from the IEEE. #12;CING OF POWER TRANSMISSION lines during winter that applies 33-kV, 100-kHz power. TheoverallsystemisillustratedinFigure1.Itcouldbede- ployed in two different

131

Optical fiber imaging for high speed plasma motion diagnostics: Applied to low voltage circuit breakers  

SciTech Connect (OSTI)

An integrated portable measurement system is described for the study of high speed and high temperature unsteady plasma flows such as those found in the vicinity of high current switching arcs. An array of optical fibers allows the formation of low spatial resolution images, with a maximum capture rate of 1x10{sup 6} images per second (1 MHz), with 8 bit intensity resolution. Novel software techniques are reported to allow imaging of the arc; and to measure arc trajectories. Results are presented on high current (2 kA) discharge events in a model test fixture and on the application to a commercial low voltage circuit breaker.

McBride, J. W. [School of Engineering Sciences, University of Southampton, Highfield, Southampton SO17 1BJ (United Kingdom); Balestrero, A.; Tribulato, G. [ABB SACE DIVISION, ABB S.p.A., Via Baioni, Bergamo 35 IT-24123 (Italy); Ghezzi, L. [ABB SACE DIVISION, ABB S.p.A., Viale dell'Industria, Vittuone (MI)18 IT-20010 (Italy); Cross, K. J. [Taicaan Ltd., 2 Venture Road, Southampton Science Park, Southampton, Hampshire SO16 7NP (United Kingdom)

2010-05-15T23:59:59.000Z

132

Presented by High Fidelity Direct Numerical  

E-Print Network [OSTI]

Presented by High Fidelity Direct Numerical Simulations of Turbulent Combustion Jacqueline H. Chen (PI), Chun Sang Yoo, Gaurav Bansal, Hongfeng Yu, Ajith Mascarenhas Combustion Research Facility Sandia) of turbulent combustion DNS approach and role � Fully resolve all continuum scales without using subgrid models

133

High Voltage Performance of the Beam Screen of the LHC Injection Kicker Magnets  

E-Print Network [OSTI]

The LHC injection kicker magnets include beam screens to shield the ferrite yokes against wakefields resulting from the high intensity beam. The screening is provided by conductors lodged in the inner wall of a ceramic support tube. The design of the beam screen has been upgraded to overcome limitations and permit LHC operation with increasingly higher bunch intensity and short bunch lengths: the new design also significantly reduces the electric field associated with the screen conductors, decreasing the probability of electrical breakdown. The high voltage conditioning process for the upgraded kicker magnets is presented and discussed. In addition a test setup has been utilized to study flashover, on the inner wall of the ceramic tube, as a function of both applied voltage and vacuum pressure: results from the test setup are presented.

Barnes, MJ; Bregliozzi, G; Calatroni, S; Costa Pinto, P; Day, H; Ducimetière, L; Kramer, T; Namora, V; Mertens, V; Taborelli, M

2014-01-01T23:59:59.000Z

134

Voltage stabilization system in traction substation of urban electric transport  

Science Journals Connector (OSTI)

The direct current-voltage stabilization system using a high-frequency link in traction substations of urban electric transport based on applying...

S. V. Shapiro; S. F. Muftiev

2011-02-01T23:59:59.000Z

135

Round-robin artificial contamination test on high voltage dc insulators  

SciTech Connect (OSTI)

This paper summarizes the results of a worldwide round-robin test of high voltage dc (HVDC) insulators, which was carried out in six laboratories aiming at standardization of the method for artificial contamination tests on HVDC insulators. Flashover characteristics of three kinds of specimens were evaluated by the clean fog and the salt fog procedures. Sufficient information is now available to allow the preparation of provisional international specifications for artificial contamination testing of HVDC insulators.

Naito, K.; Schneider, H.M.

1995-07-01T23:59:59.000Z

136

Qualification High Voltage Testing of Short Triax HTS Cables in the Laboratory  

SciTech Connect (OSTI)

In order to qualify the electrical insulation design of future HTS cables installed in the electric grid, a number of high voltage qualification tests are generally performed in the laboratory on either single-phase model cables and/or actual three-phase cable samples. Prior to installation of the 200-m Triax HTS cable at the American Electric Power Bixby substation near Columbus, Ohio, in September, 2006, such tests were conducted on both single-phase model cables made at ORNL and tri-axial cable sections cut off from cable made on a production run. The three-phase tri-axial design provides some specific testing challenges since the ground shield and three phases are concentric about a central former with each phase separated by dielectric tape insulation immersed in liquid nitrogen. The samples were successfully tested and qualified for partial discharge inception, AC withstand, and lightning impulse where voltage is applied to one phase with the other phases grounded. In addition one of the phase pairs was tested for dc withstand as a ldquoworst caserdquo scenario to simulate the effect of VLF (Very Low Frequency) tests on the actual cable installed at the Bixby site. The model and prototype cables will be described and the high voltage test results summarized.

James, David Randy [ORNL; Sauers, Isidor [ORNL; Ellis, Alvin R [ORNL; Tuncer, Enis [ORNL; Gouge, Michael J [ORNL; Demko, Jonathan A [ORNL; Duckworth, Robert C [ORNL; Rey, Christopher M [ORNL

2009-01-01T23:59:59.000Z

137

Energy-Efficient Melting and Direct Delivery of High Quality...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Energy-Efficient Melting and Direct Delivery of High Quality Molten Aluminum Energy-Efficient Melting and Direct Delivery of High Quality Molten Aluminum itmdelivery.pdf More...

138

Highly Energy Efficient Directed Green Liquor Utilization (D...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Highly Energy Efficient Directed Green Liquor Utilization (D-GLU) Pulping Highly Energy Efficient Directed Green Liquor Utilization (D-GLU) Pulping This factsheet describes a...

139

Influence of energy contributions to a high-voltage atmospheric-pressure discharge on the efficiency of conversion of ethanol  

Science Journals Connector (OSTI)

The results of experimental investigations of the conversion of ethanol in a high-voltage atmospheric-pressure discharge have been presented. The influence of the energy parameters of the discharge on the yield a...

S. A. Zhdanok; A. V. Krauklis; P. P. Samtsov…

2006-11-01T23:59:59.000Z

140

A high voltage test stand for electron gun qualification for LINACs  

SciTech Connect (OSTI)

An electron gun lest stand has been developed at RRCAT. The test stand consists of a high voltage pulsed power supply, electron gun filament supply, grid supply, UHV system and electron gun current measurement system. Several electron guns developed indigenously were evaluated on this test stand. The shielding is provided for the electron gun set up. Electron gun tests can be tested upto 55 kV with pulse width of 15 microsecs and pulse repetition rates up to 200 Hz. The technical details of the subsystems are furnished and results of performance of the test stand have been reported in this paper. (author)

Wanmode, Yashwant D.; Mulchandani, J.; Acharya, M.; Bhisikar, A.; Singh, H.G.; Shrivastava, Purushottam, E-mail: yash@rrcat.gov.in [Pulsed High Power Microwave Section, Raja Ramanna Centre for Advanced Technology, Indore (India)

2011-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage direct" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

A Fusing Switch for Fault Suppression in the SNS High Voltage Converter Modulators  

SciTech Connect (OSTI)

The High Voltage Converter Modulators (HVCMs) at the Spallation Neutron Source (SNS) have operated in excess of a combined 250,000 hours. Performance and reliability improvements to the HVCM are ongoing to increase modulator availability as accelerator system demands increase. There is a relatively large amount of energy storage in the HVCMs, {approx}180 kJ. This energy has the potential to dump into unsuppressed faults, cause damage, and increase the time to repair. The 'fusing switch' concept involves isolation of this stored energy from the location of the most common faults. This paper introduces this concept and its application to the HVCMs.

Kemp, Mark A.; Burkhart, Craig; Nguyen, Minh N.; /SLAC; Anderson, David E.; /Oak Ridge

2009-08-03T23:59:59.000Z

142

High voltage power supplies for the neutral beam injectors of the stellarator TJ-II  

Science Journals Connector (OSTI)

Neutral beam injection will be available for the second experimental phase of TJ-II. Two injectors, set in co-counter configuration, will inject into the plasma two 40 keV H0 beams, each of up to 1 MW. The two high voltage power supplies to feed the acceleration grids of the injectors, described in this paper, are of the transformer–rectifier type, taking their primary energy from a pulsed flywheel generator, and are coupled to the acceleration grids through a switching device. This environment effectively sets the main operation limits and protection requirements of the power supplies.

J Alonso; M Liniers; L Mart??nez Laso; E Jauregi; C Luc??a; F Valcárcel

2001-01-01T23:59:59.000Z

143

Design Techniques for High Speed Low Voltage and Low Power Non-Calibrated Pipeline Analog to Digital Converters  

E-Print Network [OSTI]

DESIGN TECHNIQUES FOR HIGH SPEED LOW VOLTAGE AND LOW POWER NON-CALIBRATED PIPELINE ANALOG TO DIGITAL CONVERTERS A Dissertation by RIDA SHAWKY ASSAAD Submitted to the Office of Graduate Studies of Texas A&M University... in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY December 2009 Major Subject: Electrical Engineering DESIGN TECHNIQUES FOR HIGH SPEED LOW VOLTAGE AND LOW POWER NON-CALIBRATED PIPELINE ANALOG TO DIGITAL...

Assaad, Rida Shawky

2011-02-22T23:59:59.000Z

144

High-voltage nanosecond pulses in a low-pressure radio-frequency discharge  

Science Journals Connector (OSTI)

An influence of a high-voltage (3–17 kV) 20 ns pulse on a weakly-ionized low-pressure (0.1–10 Pa) capacitively coupled radiofrequency (RF) argon plasma is studied experimentally. The plasma evolution after pulse exhibits two characteristic regimes: a bright flash, occurring within 100 ns after the pulse (when the discharge emission increases by 2–3 orders of magnitude over the steady-state level), and a dark phase, lasting a few hundreds ?s (when the intensity of the discharge emission drops significantly below the steady-state level). The electron density increases during the flash and remains very large at the dark phase. 1D3V particle-in-cell simulations qualitatively reproduce both regimes and allow for detailed analysis of the underlying mechanisms. It is found that the high-voltage nanosecond pulse is capable of removing a significant fraction of plasma electrons out of the discharge gap, and that the flash is the result of the excitation of gas atoms, triggered by residual electrons accelerated in the electric field of immobile bulk ions. The secondary emission from the electrodes due to vacuum UV radiation plays an important role at this stage. High-density plasma generated during the flash provides efficient screening of the RF field (which sustains the steady-state plasma). This leads to the electron cooling and, hence, onset of the dark phase.

M. Y. Pustylnik; L. Hou; A. V. Ivlev; L. M. Vasilyak; L. Couëdel; H. M. Thomas; G. E. Morfill; V. E. Fortov

2013-06-10T23:59:59.000Z

145

The Matrix Converter Drive Performance Under Abnormal Input Voltage Conditions  

E-Print Network [OSTI]

that generates variable magnitude variable frequency output voltage from the ac utility line. It has high power voltage disturbance related performance issues of the MC drive. Since the MC is a direct frequencyThe Matrix Converter Drive Performance Under Abnormal Input Voltage Conditions Jun-Koo Kang

Hava, Ahmet

146

Measurement of low radioactivity background in a high voltage cable by high resolution inductively coupled plasma mass spectrometry  

SciTech Connect (OSTI)

The measurement of naturally occurring low level radioactivity background in a high voltage (HV) cable by high resolution inductively coupled plasma mass spectrometry (HR ICP MS) is presented in this work. The measurements were performed at the Chemistry Service of the Gran Sasso National Laboratory. The contributions to the radioactive background coming from the different components of the heterogeneous material were separated. Based on the mass fraction of the cable, the whole contamination was calculated. The HR ICP MS results were cross-checked by gamma ray spectroscopy analysis that was performed at the low background facility STELLA (Sub Terranean Low Level Assay) of the LNGS underground lab using HPGe detectors.

Vacri, M. L. di; Nisi, S.; Balata, M. [Gran Sasso National Laboratory, Chemistry Service, SS 17bis km 18.910, 67100 Assergi (Aq) (Italy)] [Gran Sasso National Laboratory, Chemistry Service, SS 17bis km 18.910, 67100 Assergi (Aq) (Italy)

2013-08-08T23:59:59.000Z

147

Monte Carlo method for estimating backflashover rates on high voltage transmission lines  

Science Journals Connector (OSTI)

Abstract This paper presents a novel Monte-Carlo based model for the analysis of backflashover rate (BFOR) on high voltage transmission lines. The proposed model aims to take into the account following aspects of the BFOR phenomenon: transmission line (TL) route keraunic level(s), statistical depiction of lightning-current parameters (including statistical correlation), electrogeometric model of lightning attachment, frequency-dependence of TL parameters and electromagnetic coupling effects, tower geometry and surge impedance, tower grounding impulse impedance (with soil ionization), lightning-surge reflections from adjacent towers, non-linearity of the insulator strings flashover characteristic, distribution of lightning strokes along the TL span and power frequency voltage. In the analysis of the BFOR, special attention is given to the influences emanating from the insulator strings flashover characteristic and lightning statistics. The model could be applied to the transmission line as a whole or some of its portions, e.g. first several towers emanating from the substation or several towers crossing a mountain ridge.

Petar Sarajcev

2015-01-01T23:59:59.000Z

148

Measurements of the volt-ampere characteristics and the breakdown voltages of direct-current helium and hydrogen discharges in microgaps  

SciTech Connect (OSTI)

The discharge phenomena for micro meter gap sizes include many interesting problems from engineering and physical perspectives. In this paper, the authors deal with the experimental and theoretical results of the breakdown voltage and current-voltage characteristics of the direct-current helium and hydrogen discharges. The measurements were performed at a constant pressure of around one atmosphere, while varying the gap size between two parallel plane tungsten electrodes between 1??m and 100??m. From the measured breakdown voltage curves, the effective yields and the ionization coefficients were derived for both gases. Present data for the ionization coefficients correlate with the data obtained for the breakdown voltage curves measured for fixed 100??m interelectrode separation. The current-voltage characteristics were plotted for the various gap sizes illustrating the role of the field emission effects in the microgaps. Based on the Fowler-Nordheim theory, the enhancement factors were determined. The gap spacing dependence of the field emission current can be explained by the introduction of two ideas, the first being a space charge effect by emitted electrons, and the second a change in the breakdown mechanism. Experimental results, presented here, demonstrate that Townsend phenomenology breaks down when field emission becomes the key mechanism affecting the breakdown and deforming the left hand side of the breakdown voltage curves.

Klas, M.; Matej?ik, Š. [Department of Experimental Physics, Comenius University, Mlynskadolina F2, 84248 Bratislava (Slovakia); Radjenovi?, B.; Radmilovi?-Radjenovi?, M. [Institute of Physics, University of Belgrade, P.O. Box 57, 11080 Belgrade (Serbia)

2014-10-15T23:59:59.000Z

149

Monolithically interconnected GaAs solar cells: A new interconnection technology for high voltage solar cell output  

SciTech Connect (OSTI)

Photovoltaic linear concentrator arrays can benefit from high performance solar cell technologies being developed at AstroPower. Specifically, these are the integration of thin GaAs solar cell and epitaxial lateral overgrowth technologies with the application of monolithically interconnected solar cell (MISC) techniques. This MISC array has several advantages which make it ideal for space concentrator systems. These are high system voltage, reliable low cost monolithically formed interconnections, design flexibility, costs that are independent of array voltage, and low power loss from shorts, opens, and impact damage. This concentrator solar cell will incorporate the benefits of light trapping by growing the device active layers over a low-cost, simple, PECVD deposited silicon/silicon dioxide Bragg reflector. The high voltage-low current output results in minimal 12R losses while properly designing the device allows for minimal shading and resistance losses. It is possible to obtain open circuit voltages as high as 67 volts/cm of solar cell length with existing technology. The projected power density for the high performance device is 5 kW/m for an AMO efficiency of 26% at 1 5X. Concentrator solar cell arrays are necessary to meet the power requirements of specific mission platforms and can supply high voltage power for electric propulsion systems. It is anticipated that the high efficiency, GaAs monolithically interconnected linear concentrator solar cell array will enjoy widespread application for space based solar power needs. Additional applications include remote man-portable or ultra-light unmanned air vehicle (UAV) power supplies where high power per area, high radiation hardness and a high bus voltage or low bus current are important. The monolithic approach has a number of inherent advantages, including reduced cost per interconnect and increased reliability of array connections. There is also a high potential for a large number of consumer products.

Dinetta, L.C.; Hannon, M.H.

1995-10-01T23:59:59.000Z

150

ANUEADflM-31 Electric Power High-Voltage Transmission Lines:  

Office of Scientific and Technical Information (OSTI)

ANUEADflM-31 ANUEADflM-31 Electric Power High-Voltage Transmission Lines: Design Options, Cost, and Electric and Magnetic Field Levels by J.B. Stoffel,' E.D. Pentecost, R.D. Roman, and P.A. Traczyk Environmental Assessment Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439 November 1994 Work sponsored by United States Department of Energy, Assistant Secretary for Fossil Energy, Office of Fuels Program Stoffel is affiliated with Argonne's Electronics and Computing Technologies Division. D4SlRlBUTlON OF THIS DOCUMENT IS UNLiMltEb - . - . - . - . ... - , . ^ ~ .. , . . . , . . _ I T h i s report i s printed on recycled paper. @ . . .. . ' . . . A :_ - .. ., . . DISCLAIMER This report was .prepared as an account of work sponsored by an agency of the United States Government. Neither

151

ESS 2012 Peer Review - Low Cost, Manufacturable High Voltage Power Module for ESS - Brandon Passmore, APEI  

Broader source: Energy.gov (indexed) [DOE]

W. Research Center Blvd. * Fayetteville, AR 72701 * (479) 443-5759 W. Research Center Blvd. * Fayetteville, AR 72701 * (479) 443-5759 Design and Development of a Low Cost, Manufacturable High Voltage Power Module for Energy Storage Systems Phase I SBIR September 27, 2012 Brandon Passmore, PhD Sr. Electronics Packaging Research Engineer Email: bpassmo@apei.net Acknowledgements * I would like to thank Dr. Imre Gyuk of the DOE Energy Storage Systems Program and Dr. Stan Atcitty for technical support * I would also like to thank 2 Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

152

Artificial SEI Enables High-Voltage Lithium-ion Batteries | ornl.gov  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Functional Materials for Energy Functional Materials for Energy Artificial SEI Enables High-Voltage Lithium-ion Batteries September 03, 2013 Efficacy of Lipon coating as an artificial SEI for suppression of electrolyte decomposition on a 5V spinel cathode: coulombic efficiency was measured versus cycle numbers at samples with different coating thickness. An artificial solid electrolyte interphase (SEI) of lithium phosphorus oxynitride (Lipon) enables the use of 5V cathode materials with conventional carbonate electrolytes in lithium-ion batteries. Five volt cathode materials, such as LiNi0.5Mn1.5O4, are desirable to provide higher energy, however conventional carbonate electrolytes decompose above 4.5V compromising the battery performance. This work shows that Lipon coating suppresses the electrolyte decomposition, as measured by the

153

High open circuit voltages of solar cells based on quantum dot and dye hybrid-sensitization  

SciTech Connect (OSTI)

A type of solar cell based on quantum dot (QD) and dye hybrid-sensitized mesoporous TiO{sub 2} film electrode was designed and reported. The electrode was consisted of a TiO{sub 2} nanoparticle (NP) thin film layer sensitized with CdS quantum dot (QD) and an amorphous TiO{sub 2} coated TiO{sub 2} NP thin film layer that sensitized with C106 dye. The amorphous TiO{sub 2} layer was obtained by TiCl{sub 4} post-treatment to improve the properties of solar cells. Research showed that the solar cells fabricated with as-prepared hybrid-sensitized electrode exhibited excellent photovoltaic performances and a fairly high open circuit voltage of 796?mV was achieved.

Zhao, Yujie; Zhao, Wanyu; Chen, Jingkuo; Li, Huayang; Fu, Wuyou, E-mail: hari@hpu.edu.cn, E-mail: fuwy56@163.com; Sun, Guang; Cao, Jianliang; Zhang, Zhanying [School of Materials Science and Engineering and Cultivating Base for Key Laboratory of Environment-friendly Inorganic Materials in University of Henan Province, Henan Polytechnic University, Jiaozuo 454000 (China)] [School of Materials Science and Engineering and Cultivating Base for Key Laboratory of Environment-friendly Inorganic Materials in University of Henan Province, Henan Polytechnic University, Jiaozuo 454000 (China); Bala, Hari, E-mail: hari@hpu.edu.cn, E-mail: fuwy56@163.com [School of Materials Science and Engineering and Cultivating Base for Key Laboratory of Environment-friendly Inorganic Materials in University of Henan Province, Henan Polytechnic University, Jiaozuo 454000 (China) [School of Materials Science and Engineering and Cultivating Base for Key Laboratory of Environment-friendly Inorganic Materials in University of Henan Province, Henan Polytechnic University, Jiaozuo 454000 (China); College of Chemistry and Chemical Engineering, Inner Mongolia University for the Nationalities, Tongliao 028043 (China)

2014-01-06T23:59:59.000Z

154

Constructing ‘population’ criteria for the comparison of different options for a high voltage line route  

Science Journals Connector (OSTI)

This paper presents a method for comparing the sensitiveness of people to different possible options for the route of High Voltage transmission lines. It has been tested on practical cases. First, we create special dimensions and scales in order to evaluate the different zones of a studied area. Then, the different options for the route of HV lines (which are a succession of different zones) have to be compared. The construction of criteria permitting the comparison of different options raises a theoretical issue: how to punctualise the geographic distribution or the grades of the different zones of an option, in order to reflect preferences? Different methods of punctualisation are proposed which could apply to other cases. But the purpose of the paper is merely to show that these methods of punctualisation are not neutral, they cannot reflect all the characteristics of a distribution of grades.

Nathalie Grassin

1986-01-01T23:59:59.000Z

155

High Temperature 300°C Directional Drilling System  

Broader source: Energy.gov [DOE]

Project objective: provide a directional drilling system that can be used at environmental temperatures of up to 300°C; and at depths of 10; 000 meters.

156

Highly Directional Antenna for Improved Communications - Energy...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

in some directions while suppressing it in others, and are used in applications such as satellite communications, wireless communications, surveillance, and weather radar. As...

157

High Temperature 300°C Directional Drilling System  

Broader source: Energy.gov (indexed) [DOE]

300C Directional Drilling System John Macpherson Baker Hughes Oilfield Operations DE-EE0002782 May 19, 2010 This presentation does not contain any proprietary confidential, or...

158

Low-Variation 1 MHz Clock Generator,High Sensitivity Linear Voltage-to-Frequency Converter,and High-PSR Bias Circuit for NTSC SYNC Separation.  

E-Print Network [OSTI]

??This thesis includes three topics. The first topic is a low-variation 1 MHz clock generator. The second one is a high sensitivity linear voltage-to-frequency converter.… (more)

Lee, Tzung-Je

2004-01-01T23:59:59.000Z

159

New live line tester for porcelain suspension insulators on high-voltage power lines  

SciTech Connect (OSTI)

Suspension insulator assemblies known as insulator strings are used in overhead power transmission lines to mechanically support high-voltage conductors while providing adequate insulation to withstand switching and lightning overvoltages. Since the useful life in service of the individual insulator elements making up these strings is hard to predict, they must be verified periodically to insure that adequate line reliability is maintained at all times. Over the years many testing methods have been used for this purpose, each one with its own advantages and disadvantages. Until now at Hydro-Quebec, porcelain insulators had been tested by the buzz method which simply consists of applying a short-circuit to each insulator in a string and listening for a buzz-like sound indicating a good insulator. However, safety considerations that preclude short-circuiting insulators and other disadvantages of that method have led Hydro-Quebec to undertake and complete the development of a new insulator tester. The working principle of this new device is based on the automatic measurement and recording of the electric field along the insulator string which decreases considerably in front of an internally-shorted insulator. The tester is slid along the string while the insulators are counted automatically. The information from tests on up to 200 strings can be stored in the device to be later transferred in a host computer for interpretation and/or permanent storage. The new tester also gives information on voltage distribution along the insulator strings which can be useful for the design of future power transmission lines.

Vaillancourt, G.H.; St-Jean, M. (Hydro-Quebec, Varennes, Quebec (Canada)); Bellerive, J.P. (Hydro-Quebec, Montreal, Quebec (Canada)); Jean, C. (Positron Inc., Montreal, Quebec (Canada))

1994-01-01T23:59:59.000Z

160

High Performance Sustainable Building - DOE Directives, Delegations...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

6A, High Performance Sustainable Building by Adam Pugh Functional areas: Program Management, Project Management This Guide provides approaches for implementing the High Performance...

Note: This page contains sample records for the topic "high voltage direct" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Integrated polymer solar cells in serial architecture with patterned charge-transporting MoOx for miniature high-voltage sources  

Science Journals Connector (OSTI)

We develop miniature high-voltage sources from polymer solar cells (PSCs) with charge-transporting molybdenum oxide (MoOx) integrated in a serial architecture through sacrificial layer (SL)-assisted patterning. The MoOx layer, being patterned by the lift-off process of the SL of a hydrophobic fluorinated-polymer, as a hole transporting layer plays a critical role on the reduction of the dark current and the increase of a high open circuit voltage of an integrated PSC array. The underlying mechanism lies primarily on the elimination of the lateral charge pathways in the MoOx layer in the presence of the electrode interconnection. Two miniature voltage sources consisting of 20 PSCs and 50 PSCs are demonstrated in the operation of a liquid crystal display and an organic field-effect transistor, respectively. Our SL-assisted integration approach will be directly applicable for implementing the self-power sources made of the PSCs into a wide range of the electronic and optoelectronic devices.

Seong-Min Cho; Chang-Min Keum; Hea-Lim Park; Min-Hoi Kim; Jin-Hyuk Bae; Sin-Doo Lee

2014-01-01T23:59:59.000Z

162

A three-level buck converter to regulate a high-voltage DC-to-AC inverter  

E-Print Network [OSTI]

A three-level buck converter is designed and analyzed, and shown to be suitable as a high-voltage down converter as a pre-regulation stage for a 600 watt DC-to-AC power inverter. Topology selection for the inverter is ...

Schrock, Kenneth C

2008-01-01T23:59:59.000Z

163

Leveraging the LEDA high voltage power supply systems for the LANSCE refurbishment project  

SciTech Connect (OSTI)

The LANSCE Refurbishment Project (LANSCE-R) will revitalize the LANSCE accelerator infrastructure. Much of the equipment has been in use for over 39 years and is approaching the end of its design lifetime. As obsolescence issues make like-for-like replacements increasingly more expensive, modern systems with lower costs become a reasonable alternative. As part of the LANSCE-R project, four of the seven HV power supplies for the 805 MHz RF klystrons will be replaced. The present and future requirements for these power supplies influence the selection of replacement options. Details of the HV power supply replacement requirements and the different replacement options will be discussed. One option is to use four 95 kV, 21 A DC power supplies originally installed nearby as part of the Low Energy Demonstration Accelerator (LEDA) project. Significant material and labor cost savings can be achieved by leaving these supplies installed where they are and building a HV transport system to bring high voltage power from the existing LEDA facility to the LANSCE facility. The different replacement options will be compared based on material and labor costs as offset by long-term energy savings.

Bradley Iii, Joseph Thomas [Los Alamos National Laboratory; Rees, Daniel E [Los Alamos National Laboratory; Roybal, William T [Los Alamos National Laboratory; Young, Karen A [Los Alamos National Laboratory

2008-01-01T23:59:59.000Z

164

Redesign of the H-Bridge Switch Plate of the SNS High Voltage Converter Modulator  

SciTech Connect (OSTI)

The 1-MW High Voltage Converter Modulators [1] have operated in excess of 250,000 hours at the Spallation Neutron Source. Increased demands on the accelerator performance require increased modulator reliability. An effort is underway at SLAC National Accelerator Laboratory to redesign the modulator H-bridge switch plate with the goals of increasing reliability and performance [2]. The major difference between the SLAC design and the existing design is the use of press-pack IGBTs. Compared to other packaging options, these IGBTs have been shown to have increased performance in pulsed-power applications, have increased cooling capability, and do not fragment and disassemble during a fault event. An overview of the SLAC switch plate redesign is presented. Design steps including electrical modeling of the modulator and H-bridge, development of an integrated IGBT clamping mechanism, and fault tests are discussed. Experimental results will be presented comparing electrical performance of the SLAC switch plate to the existing switchplate under normal and fault conditions.

Kemp, M.A.; Burkhart, C.; Nguyen, M.N.; /SLAC; Anderson, D.E.; /Oak Ridge

2009-05-07T23:59:59.000Z

165

Monitoring the magnetic field in houses under 50 Hz high-voltage overhead transmission lines  

Science Journals Connector (OSTI)

This paper deals with a one-week monitoring of the 50 Hz magnetic field on the ground floor and the first floor of houses under 150, 220 and 380 kV high-voltage overhead three-phase AC transmission lines. The field strength varied with the current intensity, the conductor height, and the storey of the house. Because current intensity varies with time the magnetic field depended on the time of day and the day of the week. The recorded magnetic field ranged from 0.1 µT to 4.5 µT. The maximum value was at least 20 times weaker than the 100 µT exposure level recommended by the guidelines of the International Radiation Protection Association (IRPA) and about 140 times smaller than the 640 µT of the European Prestandard (CENELEC). The B-field was, for 99.9% of the measuring time, larger than the 0.2 µT cut-off point used to define categories of exposed and unexposed subjects in EMF epidemiological studies and, for 99.3% of the time, was greater than the 0.3 µT level used by US private engineering companies as the 'prudent avoidance' exposure limit. The weakest average magnetic field was at least 40 times larger than the 0.02 µT background value.

G. Decat; J. Van Tongerloo

1998-01-01T23:59:59.000Z

166

Electron Energy Analysis of Vacuum Discharge in High-Voltage Accelerator Tube  

Science Journals Connector (OSTI)

......measurement of the electron energy spectrum during discharge adds some new knowledge to the total voltage...authors sincerely thank Electron Energy Analysis of Vacuum Discharge...Physics, Academic Press, New York, Vol. 6, p. 297. 25......

Akio TAKAOKA; Katsumi URA; Kiyokazu YOSHIDA

1982-01-01T23:59:59.000Z

167

Novel Materials for High Efficiency Direct Methanol Fuel Cells  

Broader source: Energy.gov (indexed) [DOE]

or otherwise restricted information Novel Materials for High Efficiency Direct Methanol Fuel Cells Chris Roger and David Mountz October 1, 2009 2009 Fuel Cell Projects Kickoff...

168

Scalable High-Power Redox Capacitors with Aligned Nanoforests of Crystalline MnO2 Nanorods by High Voltage Electrophoretic Deposition  

Science Journals Connector (OSTI)

Scalable High-Power Redox Capacitors with Aligned Nanoforests of Crystalline MnO2 Nanorods by High Voltage Electrophoretic Deposition ... The scalable nanomanufacturing process is demonstrated by roll-printing an aligned forest of ?-MnO2 nanorods on a large flexible substrate (1 inch by 1 foot). ...

Sunand Santhanagopalan; Anirudh Balram; Dennis Desheng Meng

2013-02-01T23:59:59.000Z

169

High voltage capability electrical coils insulated with materials containing SF.sub.6 gas  

DOE Patents [OSTI]

A coil is made having a plurality of layers of adjacent metal conductor windings subject to voltage stress, where the windings have insulation therebetween containing a small number of minute disposed throughout its cross-section, where the voids are voids filled with SF.sub.6 gas to substitute for air or other gaseous materials in from about 60% to about 95% of the cross-sectional void volume in the insulation, thus incorporating an amount of SF.sub.6 gas in the cross-section of the insulation effective to substantially increase corona inception voltages.

Lanoue, Thomas J. (Muncie, IN); Zeise, Clarence L. (Penn Township, Allegheny County, PA); Wagenaar, Loren (Muncie, IN); Westervelt, Dean C. (Acme, PA)

1988-01-01T23:59:59.000Z

170

Room-temperature atmospheric argon plasma jet sustained with submicrosecond high-voltage pulses  

SciTech Connect (OSTI)

In this letter, an experimental study is presented to characterize a room-temperature plasma jet in atmospheric argon generated with submicrosecond voltage pulses at 4 kHz. Distinct from sinusoidally produced argon discharges that are prone to thermal runaway instabilities, the pulsed atmospheric argon plasma jet is stable and cold with an electron density 3.9 times greater than that in a comparable sinusoidal jet. Its optical emission is also much stronger. Electrical measurement suggests that the discharge event is preceded with a prebreakdown phase and its plasma stability is facilitated by the short voltage pulses.

Walsh, J. L.; Kong, M. G. [Department of Electronic and Electrical Engineering, Loughborough University, Loughborough, Leicestershire LE11 3TU (United Kingdom)

2007-11-26T23:59:59.000Z

171

Some Features of an Electrostatic Generator and Ion Source for High Voltage Research  

Science Journals Connector (OSTI)

A compact generator of the Van de Graaff type is described in which several new features have been incorporated. Short-circuit current of one milliampere is available. When operating at 600 kv as voltage supply for accelerating protons or deutersons, 130?a of charged particles at the target have been obtained from an unusual low voltage capillary arc source. In normal operation as a neutron generator, the equivalent of 15 curies of radon-beryllium is readily produced by the reaction Li+D, and 60 curies by the D on D reaction.

I. A. Getting; J. B. Fisk; H. G. Vogt

1939-12-01T23:59:59.000Z

172

High Specific Power, Direct Methanol Fuel Cell Stack  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

High Specific Power, Direct Methanol Fuel Cell Stack High Specific Power, Direct Methanol Fuel Cell Stack High Specific Power, Direct Methanol Fuel Cell Stack The present invention is a fuel cell stack including at least one direct methanol fuel cell. Available for thumbnail of Feynman Center (505) 665-9090 Email High Specific Power, Direct Methanol Fuel Cell Stack The present invention is a fuel cell stack including at least one direct methanol fuel cell. A cathode manifold is used to convey ambient air to each fuel cell, and an anode manifold is used to convey liquid methanol fuel to each fuel cell. Tie-bolt penetrations and tie-bolts are spaced evenly around the perimeter to hold the fuel cell stack together. Each fuel cell uses two graphite-based plates. One plate includes a cathode active area that is defined by serpentine channels connecting the inlet manifold

173

Impact of High Wind Penetration on the Voltage Profile of Distribution Systems  

E-Print Network [OSTI]

that the inclusion of squirrel cage induction generator (SCIG) does not have a large influence on transient stability to the inability of induction generator to support the reactive power. So, the main objective of this study generation on the voltage profile in distribution systems have been presented. The analysis is carried out

Pota, Himanshu Roy

174

Plasma Immersion Ion Implantation with a 4kV/10kHz Compact High Voltage Pulser  

SciTech Connect (OSTI)

Development of a 4 kV/10 kHz Compact High Voltage Pulser and its application to nitrogen plasma immersion ion implantation (PIII) of different materials as Si, Al alloys, SS304 stainless steel and Ti alloys are discussed. Low voltage (1-5 kV) pulses at high frequencies (up to 20 kHz for 2 kV) were obtained with maximum power delivered at 5 kV, 7 kHz. These conditions were not sufficient to reach temperatures above 200 deg. C in the samples because of short duration of the pulses. However, very shallow implantations of nitrogen in Si, Al5052, SS304 were observed by Auger electron spectroscopy and improved corrosion resistance was obtained for Al5052 when it was treated by nitrogen PIII at 2.5 kV, 5{mu}s and 5 kHz pulses.

Ueda, M.; Oliveira, R. M.; Rossi, J. O. [Associated Laboratory of Plasma, National Institute for Space Research, Av. dos Astronautas 1758, Sao Jose dos Campos, Sao Paulo (Brazil); Reuther, H. [Institute of Ion Beam Physics and Materials Research, Rossendorf, Dresden (Germany); Silva, G. [Associated Laboratory of Plasma, National Institute for Space Research, Av. dos Astronautas 1758, Sao Jose dos Campos, Sao Paulo (Brazil); Department of Aeronautics and Mechanics, Technological Institute of Aeronautics, Sao Jose dos Campos, Sao Paulo (Brazil)

2006-11-13T23:59:59.000Z

175

Using Dielectric Losses to De-Ice Power Transmission Lines with 100 kHz High-Voltage  

E-Print Network [OSTI]

capable of exciting a 1 m test line to 30 kV has been tested and show to be capable of removing a 7 mm iceUsing Dielectric Losses to De-Ice Power Transmission Lines with 100 kHz High-Voltage Excitation J DIELECTRIC LOSSES TO DE-ICE POWER TRANSMISSION LINES . . . 1 Using Dielectric Losses to De-Ice Power

176

Influence of high voltage atmospheric cold plasma process parameters and role of relative humidity on inactivation of Bacillus atrophaeus spores inside a sealed package  

Science Journals Connector (OSTI)

SummaryBackground Non-thermal plasma has received much attention for elimination of microbial contamination from a range of surfaces. Aim This study aimed to determine the effect of a range of dielectric barrier discharge high voltage atmospheric cold plasma (HVACP) parameters for inactivation of Bacillus atrophaeus spores inside a sealed package. Methods A sterile polystyrene Petri dish containing B. atrophaeus spore strip (spore population 2.3 × 106/strip i.e. 6.36 log10/strip) was placed in a sealed polypropylene container and was subjected to HVACP treatment. The HVACP discharge was generated between two aluminium plate electrodes using a high voltage of 70 kVRMS. The effects of process parameters, including treatment time, mode of exposure (direct/indirect), and working gas types, were evaluated. The influence of relative humidity on HVACP inactivation efficacy was also assessed. The inactivation efficacy was evaluated using colony counts. Optical absorption spectroscopy (OAS) was used to assess gas composition following HVACP exposure. Findings A strong effect of process parameters on inactivation was observed. Direct plasma exposure for 60 s resulted in ?6 log10 cycle reduction of spores in all gas types tested. However, indirect exposure for 60 s resulted in either 2.1 or 6.3 log10 cycle reduction of spores depending on gas types used for HVACP generation. The relative humidity (RH) was a critical factor in bacterial spore inactivation by HVACP, where a major role of plasma-generated species other than ozone was noted. Direct and indirect HVACP exposure for 60 s at 70% RH recorded 6.3 and 5.7 log10 cycle reduction of spores, respectively. Conclusion In summary, a strong influence of process parameters on spore inactivation was noted. Rapid in-package HVACP inactivation of bacterial spores within 30–60 s demonstrates the promising potential application for reduction of spores on medical devices and heat-sensitive materials.

S. Patil; T. Moiseev; N.N. Misra; P.J. Cullen; J.P. Mosnier; K.M. Keener; P. Bourke

2014-01-01T23:59:59.000Z

177

Identification of ions near HVDC (high-voltage direct-current) transmission lines: Final report  

SciTech Connect (OSTI)

Positive and negative ion species were identified and studied at two separate field sites and one laboratory site. The first field study was conducted under an operating HVDC transmission line. The second was near a HVDC test line and measurements were performed with the line in both an energized and de-energized state. During clear, sunny days HSO/sub 4//sup /minus///center dot/H/sub 2/SO/sub 4/ was observed to be the dominant negative ion in the natural ion spectrum. At night, however, HSO/sub 4//sup /minus// core ions virtually disappeared, and were replaced by NO/sub 3//sup /minus// core ions and their first nitric acid cluster. Both negative spectra also typically contained lesser concentrations of the malonate ion. The transmission line negative spectra were similar but were typically dominated by the NO/sub 3//sup /minus// core ions during both day and night. The positive ions observed under HVDC lines were typically either NH/sub 4//sup +/ or C/sub 5/H/sub 6/N/sup +/, which reacted with higher proton affinity species (such as methylpyridines, trimethylamine and quinoline) farther from or in the absence of the transmission line. The observed differences between natural and anthropogenic ion spectra near HVDC lines are attributed primarily to a shortening of ion lifetimes by the strong electric field associated with the HVDC lines. One exception is the production of potassium and probably sodium based ions from the decomposition of insects in transmission line coronas. 22 refs., 29 figs.

Eisele, F.L.

1989-05-01T23:59:59.000Z

178

Optical voltage reference  

DOE Patents [OSTI]

An optical voltage reference for providing an alternative to a battery source is described. The optical reference apparatus provides a temperature stable, high precision, isolated voltage reference through the use of optical isolation techniques to eliminate current and impedance coupling errors. Pulse rate frequency modulation is employed to eliminate errors in the optical transmission link while phase-lock feedback is employed to stabilize the frequency to voltage transfer function. 2 figures.

Rankin, R.; Kotter, D.

1994-04-26T23:59:59.000Z

179

Ignition distributor voltage generator  

SciTech Connect (OSTI)

This patent describes a voltage pulse generator and ignition distributor comprising, a base, a shaft rotatably supported by the base, a distributor cap supported by the base having a center electrode and circumferentially spaced outer electrodes. The pulse generator and ignition distribution also include a first rotor driven by the shaft formed of electrical insulating material having electrically conductive means connected to the center terminal and a portion that rotates past the outer electrodes. The portion of the electrically conductive means that rotates past the outer electrodes is spaced from the outer electrodes to form a gap therebetween. A voltage pulse generator comprises a second rotor driven by the shaft, at least one permanent magnet and an annular pickup coil supported by the base. The pickup coil has inner turns and outer turns, the beginning turn of the inner turns connected to a first lead and the last turn of the outer turns connected to a second lead, the outer turns enclosing the inner turns. The pickup coil also has a circuit connected directly between the second lead and ground which is operative to provide a direct conductive path to ground for high frequency energy capacitively coupled to the outer turns from the gap discharge between the electrically conductive means of the first rotor and an outer electrode, the outer turns forming a grounded shield for the inner turns.

Boyer, J.A.

1986-11-04T23:59:59.000Z

180

Experimental investigation of dielectric barrier discharge plasma actuators driven by repetitive high-voltage nanosecond pulses with dc or low frequency sinusoidal bias  

SciTech Connect (OSTI)

Experimental studies were conducted of a flow induced in an initially quiescent room air by a single asymmetric dielectric barrier discharge driven by voltage waveforms consisting of repetitive nanosecond high-voltage pulses superimposed on dc or alternating sinusoidal or square-wave bias voltage. To characterize the pulses and to optimize their matching to the plasma, a numerical code for short pulse calculations with an arbitrary impedance load was developed. A new approach for nonintrusive diagnostics of plasma actuator induced flows in quiescent gas was proposed, consisting of three elements coupled together: the schlieren technique, burst mode of plasma actuator operation, and two-dimensional numerical fluid modeling. The force and heating rate calculated by a plasma model was used as an input to two-dimensional viscous flow solver to predict the time-dependent dielectric barrier discharge induced flow field. This approach allowed us to restore the entire two-dimensional unsteady plasma induced flow pattern as well as characteristics of the plasma induced force. Both the experiments and computations showed the same vortex flow structures induced by the actuator. Parametric studies of the vortices at different bias voltages, pulse polarities, peak pulse voltages, and pulse repetition rates were conducted experimentally. The significance of charge buildup on the dielectric surface was demonstrated. The charge buildup decreases the effective electric field in the plasma and reduces the plasma actuator performance. The accumulated surface charge can be removed by switching the bias polarity, which leads to a newly proposed voltage waveform consisting of high-voltage nanosecond repetitive pulses superimposed on a high-voltage low frequency sinusoidal voltage. Advantages of the new voltage waveform were demonstrated experimentally.

Opaits, Dmitry F.; Likhanskii, Alexandre V.; Neretti, Gabriele; Zaidi, Sohail; Shneider, Mikhail N.; Miles, Richard B. [Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544 (United States); Macheret, Sergey O. [Lockheed Martin Aeronautics Company, Palmdale, California 93599 (United States)

2008-08-15T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage direct" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
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181

High-Power Directional Emission from Microlasers with Chaotic Resonators  

E-Print Network [OSTI]

High-power and highly directional semiconductor cylinder-lasers based on an optical resonator with deformed cross section are reported. In the favorable directions of the far-field, a power increase of up to three orders of magnitude over the conventional circularly symmetric lasers was obtained. A "bow-tie"-shaped resonance is responsible for the improved performance of the lasers in the higher range of deformations, in contrast to "whispering-gallery"-type modes of circular and weakly deformed lasers. This resonator design, although demonstrated here in midinfrared quantum-cascade lasers, should be applicable to any laser based on semiconductors or other high-refractive index materials.

Claire Gmachl; Federico Capasso; E. E. Narimanov; Jens U. Noeckel; A. Douglas Stone; Jerome Faist; Deborah L. Sivco; Alfred Y. Cho

1998-06-15T23:59:59.000Z

182

A high-stability scanning tunneling microscope achieved by an isolated tiny scanner with low voltage imaging capability  

SciTech Connect (OSTI)

We present a novel homebuilt scanning tunneling microscope (STM) with high quality atomic resolution. It is equipped with a small but powerful GeckoDrive piezoelectric motor which drives a miniature and detachable scanning part to implement coarse approach. The scanning part is a tiny piezoelectric tube scanner (industry type: PZT-8, whose d{sub 31} coefficient is one of the lowest) housed in a slightly bigger polished sapphire tube, which is riding on and spring clamped against the knife edges of a tungsten slot. The STM so constructed shows low back-lashing and drifting and high repeatability and immunity to external vibrations. These are confirmed by its low imaging voltages, low distortions in the spiral scanned images, and high atomic resolution quality even when the STM is placed on the ground of the fifth floor without any external or internal vibration isolation devices.

Wang, Qi; Wang, Junting; Lu, Qingyou, E-mail: qxl@ustc.edu.cn [High Magnetic Field Laboratory, Chinese Academy of Sciences and University of Science and Technology of China, Hefei, Anhui 230026 (China) [High Magnetic Field Laboratory, Chinese Academy of Sciences and University of Science and Technology of China, Hefei, Anhui 230026 (China); Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, Anhui 230026 (China); Hou, Yubin [High Magnetic Field Laboratory, Chinese Academy of Sciences and University of Science and Technology of China, Hefei, Anhui 230026 (China)] [High Magnetic Field Laboratory, Chinese Academy of Sciences and University of Science and Technology of China, Hefei, Anhui 230026 (China)

2013-11-15T23:59:59.000Z

183

Improving the performance of stainless-steel DC high voltage photoelectron gun cathode electrodes via gas conditioning with helium or krypton  

SciTech Connect (OSTI)

Gas conditioning was shown to eliminate field emission from cathode electrodes used inside DC high voltage photoelectron guns, thus providing a reliable means to operate photoguns at higher voltages and field strengths. Measurements and simulation results indicate that gas conditioning eliminates field emission from cathode electrodes via two mechanisms: sputtering and implantation, with the benefits of implantation reversed by heating the electrode. We have studied five stainless steel electrodes (304L and 316LN) that were polished to approximately 20 nm surface roughness using diamond grit, and evaluated inside a high voltage apparatus to determine the onset of field emission as a function of voltage and field strength. The field emission characteristics of each electrode varied significantly upon the initial application of voltage but improved to nearly the same level after gas conditioning using either helium or krypton, exhibiting less than 10 pA field emission at ?225 kV bias voltage with a 50 mm cathode/anode gap, corresponding to a field strength of ~13 MV/m. Field emission could be reduced with either gas, but there were conditions related to gas choice, voltage and field strength that were more favorable than others.

Bastaninejad, Mahzad [ODU; Elmustafa, Abdelmageed [ODU; Forman, Eric I. [JLAB; Clark, James [JLAB; Covert, Steven R. [JLAB; Grames, Joseph M. [JLAB; Hansknecht, John C. [JLAB; Hernandez-Garcia, Carlos [JLAB; Poelker, Bernard [JLAB; Suleiman, Riad S. [JLAB

2014-10-01T23:59:59.000Z

184

Electro-optical voltage sensor head  

DOE Patents [OSTI]

A miniature electro-optic voltage sensor system capable of accurate operation at high voltages. The system employs a transmitter, a sensor disposed adjacent to but out of direct electrical contact with a conductor on which the voltage is to be measured, a detector, and a signal processor. The transmitter produces a beam of electromagnetic radiation which is routed into the sensor where the beam undergoes the Pockels electro-optic effect. The electro-optic effect causes phase shifting in the beam, which is in turn converted to a pair of independent beams, from which the voltage of a system based on its E-field is determined when the two beams are normalized by the signal processor. The sensor converts the beam by splitting the beam in accordance with the axes of the beam's polarization state (an ellipse whose ellipticity varies between -1 and +1 in proportion to voltage) into at least two AM signals. These AM signals are fed into a signal processor and processed to determine the voltage between a ground conductor and the conductor on which voltage is being measured.

Woods, Gregory K. (Idaho Falls, ID)

1998-01-01T23:59:59.000Z

185

Directed Enzyme Evolution and High-Throughput Screening  

E-Print Network [OSTI]

into a commercial process relies on the availability of those with high activity and stability under process optimization process, whereby the fittest variants are selected from an ensemble of mutants [3]. Directed for process scientists today. Choosing the appropriate methods of library generation and screening

Zhao, Huimin

186

Direct-Write Piezoelectric Polymeric Nanogenerator with High Energy Conversion  

E-Print Network [OSTI]

Direct-Write Piezoelectric Polymeric Nanogenerator with High Energy Conversion Efficiency Chieh have shown repeatable and consistent electrical outputs with energy conversion efficiency an order for efficient conversion of mechanical energy into electricity. Recent work in the field of nanomaterials has

Lin, Liwei

187

Design and applications of a flicker voltage generator  

SciTech Connect (OSTI)

In this paper, a 200W flicker voltage generator is made by using microcomputers and linear amplification circuits. The modulation amplitudes and frequencies based on the UIE {Delta}V{sub 10} evaluation can be arbitrarily assigned by software with high accuracy. The flicker voltage signals measured at the customer side also can be re-generated. Some applications, such as evaluating the effects of flicker voltage on incandescent and compact fluorescent lamps (CFLs), are also made. From experimental tests by use of the flicker voltage generator, the properties of some compact fluorescent lamps and incandescent lamps are compared. Those properties describe the relation between input voltage variation and output flux of lamps, such that there is direct description of influences of flicker voltages on lamps.

Chang, W.N.; Wu, C.J. [National Taiwan Inst. of Tech., Peitow-Taipei (Taiwan, Province of China). Dept. of Electrical Engineering

1995-12-31T23:59:59.000Z

188

ANUEADflM-31 Electric Power High-Voltage Transmission Lines:  

Office of Scientific and Technical Information (OSTI)

formulated fluid that is kept under high pressure. This fluid helps to dissipate the power loss heat generated by the conductors. The construction costs in 1991 dollars for...

189

Acceleration Factors for Damp-Heat and HAST with High Voltage...  

Broader source: Energy.gov (indexed) [DOE]

High PID Resistant Cross-Linked Encapsulnt Based on Polyolefin SOLAR ASCE Comparing Accelerated Testing and Outdoor Exposure Agenda for the PV Module Reliability Workshop,...

190

A High-Frequency Resonant Inverter Topology With Low-Voltage Stress  

E-Print Network [OSTI]

This paper presents a new switched-mode resonant inverter, which we term the inverter, that is well suited to operation at very high frequencies and to rapid on/off control. Features of this inverter topology include low ...

Rivas, Juan M.

191

Direct coupling of pulsed radio frequency and pulsed high power in novel pulsed power system for plasma immersion ion implantation  

SciTech Connect (OSTI)

A novel power supply system that directly couples pulsed high voltage (HV) pulses and pulsed 13.56 MHz radio frequency (rf) has been developed for plasma processes. In this system, the sample holder is connected to both the rf generator and HV modulator. The coupling circuit in the hybrid system is composed of individual matching units, low pass filters, and voltage clamping units. This ensures the safe operation of the rf system even when the HV is on. The PSPICE software is utilized to optimize the design of circuits. The system can be operated in two modes. The pulsed rf discharge may serve as either the seed plasma source for glow discharge or high-density plasma source for plasma immersion ion implantation (PIII). The pulsed high-voltage glow discharge is induced when a rf pulse with a short duration or a larger time interval between the rf and HV pulses is used. Conventional PIII can also be achieved. Experiments conducted on the new system confirm steady and safe operation.

Gong Chunzhi; Tian Xiubo; Yang Shiqin [State Key Laboratory of Advanced Welding Production and Technology, School of Materials Science and Engineering, Harbin Institute of Technology, 150001 Harbin (China); Fu, Ricky K. Y.; Chu, Paul K. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong)

2008-04-15T23:59:59.000Z

192

Tetrapropyl-tetraphenyl-diindenoperylene derivative as a green absorber for high-voltage stable organic solar cells  

Science Journals Connector (OSTI)

We present small molecule organic solar cells (SMOSC) based on flat heterojunctions (FHJ) of the alternative green donor 2,3,10,11-tetrapropyl-1,4,9,12-tetraphenyl-diindeno[1,2,3-cd:1’,2’,3’-lm]perylene (P4-Ph4-DIP) and the fullerene C60. P4-Ph4-DIP absorbs in the green spectral range and thus fills the spectral gap that standard absorber materials (zinc or copper phthalocyanine for red and C60 for blue absorption) leave, thus allowing broad coverage of the sun spectrum, which is of major interest for tandem devices. The materials properties of P4-Ph4-DIP are studied, and SMOSC are characterized by current voltage, external quantum efficiency, and aging measurements. The solar cells display very high fill factors FF > 76% and open circuit voltages VOC of close to 1 V. Mismatch-corrected efficiencies of up to 1.9% are obtained. Aging measurements show that C60 in conjunction with P4-Ph4-DIP yields extremely stable devices. We observe ? 88% of the initial efficiency after 2500 h illumination at 999 mW/cm2 illumination intensity, with no observable change in short-circuit current density. Furthermore, we also show that a systematic variation of donor thickness in FHJ can be combined with transfer matrix formalism-based optical simulations and the continuity equation for excitons to reliably determine the exciton diffusion length LD. A value of 9 ± 1 nm is found for P4-Ph4-DIP.

Jan Meiss; Martin Hermenau; Wolfgang Tress; Christoph Schuenemann; Franz Selzer; Markus Hummert; Joerg Alex; Gerhard Lackner; Karl Leo; Moritz Riede

2011-04-11T23:59:59.000Z

193

Charge-pump voltage converter  

DOE Patents [OSTI]

A charge-pump voltage converter for converting a low voltage provided by a low-voltage source to a higher voltage. Charge is inductively generated on a transfer rotor electrode during its transit past an inductor stator electrode and subsequently transferred by the rotating rotor to a collector stator electrode for storage or use. Repetition of the charge transfer process leads to a build-up of voltage on a charge-receiving device. Connection of multiple charge-pump voltage converters in series can generate higher voltages, and connection of multiple charge-pump voltage converters in parallel can generate higher currents. Microelectromechanical (MEMS) embodiments of this invention provide a small and compact high-voltage (several hundred V) voltage source starting with a few-V initial voltage source. The microscale size of many embodiments of this invention make it ideally suited for MEMS- and other micro-applications where integration of the voltage or charge source in a small package is highly desirable.

Brainard, John P. (Albuquerque, NM); Christenson, Todd R. (Albuquerque, NM)

2009-11-03T23:59:59.000Z

194

A Laves phase-body-centered cubic structural relationship determined using high voltage electron microscopy  

SciTech Connect (OSTI)

High energy electron and ion irradiation of a TiCr{sub 2} Laves compound were found previously to result in a transformation to a body-centered cubic (bcc) solid solution. In the case of electron irradiation, the precipitating bcc phase exhibits preferential crystallographic orientation with respect to the initial compound crystal for irradiation temperatures above 200 K. This article presents an analysis of the electron diffraction data gathered in the course of the electron irradiation-induced Laves phase to bcc transformation in TiCr{sub 2}. A structural relationship between the bcc and Laves compound crystal lattices is determined which can account for all observations of preferentially oriented bcc precipitates. The significance of this mechanism for transformations between bcc and the Laves phases is discussed. In addition, the possible significance for deformation mechanisms of the Laves compounds is explored.

Sinkler, W. [GKSS Forschungszentrum, Geesthacht (Germany). Inst. fuer Werkstofforschung] [GKSS Forschungszentrum, Geesthacht (Germany). Inst. fuer Werkstofforschung

1996-04-01T23:59:59.000Z

195

Electro-optic voltage sensor for sensing voltage in an E-field  

DOE Patents [OSTI]

A miniature electro-optic voltage sensor system capable of accurate operation at high voltages. The system employs a transmitter, a sensor disposed adjacent to but out of direct electrical contact with a conductor on which the voltage is to be measured, a detector, and a signal processor. The transmitter produces a beam of electromagnetic radiation which is routed into the sensor where the beam undergoes the Pockels electro-optic effect. The electro-optic effect causes phase shifting in the beam, which is in turn converted to a pair of independent beams, from which the voltage of a system based on its E-field is determined when the two beams are normalized by the signal processor. The sensor converts the beam by splitting the beam in accordance with the axes of the beam's polarization state (an ellipse whose ellipticity varies between -1 and +1 in proportion to voltage) into at least two AM signals. These AM signals are fed into a signal processor and processed to determine the voltage between a ground conductor and the conductor on which voltage is being measured.

Woods, Gregory K. (Idaho Falls, ID); Renak, Todd W. (Idaho Falls, ID)

1999-01-01T23:59:59.000Z

196

A High -Temperature, High-Voltage, Fast Response Time Linear Regulator in 0.8um BCD-on-SOI.  

E-Print Network [OSTI]

??The sale of hybrid electric vehicles (HEVs) has increased tenfold from the year 2001 to 2009 [1]. With this the demand for high temperature electronics… (more)

Su, Chia Hung

2010-01-01T23:59:59.000Z

197

Recent advances in high-performance direct methanol fuel cells  

SciTech Connect (OSTI)

Direct methanol fuel cells for portable power applications have been advanced significantly under DARPA- and ARO-sponsored programs over the last five years. A liquid-feed direct methanol fuel cell developed under these programs, employs a proton exchange membrane as electrolyte and operates on aqueous solutions of methanol with air or oxygen as the oxidant. Power densities as high as 320 mW/cm{sup 2} have been demonstrated. Demonstration of five-cell stack based on the liquid-feed concept have been successfully performed by Giner Inc. and the Jet Propulsion Laboratory. Over 2000 hours of life-testing have been completed on these stacks. These fuel cells have been also been demonstrated by USC to operate on alternate fuels such as trimethoxymethane, dimethoxymethane and trioxane. Reduction in the parasitic loss of fuel across the fuel cell, a phenomenon termed as {open_quotes}fuel crossover{close_quotes} has been achieved using polymer membranes developed at USC. As a result efficiencies as high as 40% is considered attainable with this type of fuel cell. The state-of-development has reached a point where it is now been actively considered for stationary, portable and transportation applications. The research and development issues have been the subject of several previous articles and the present article is an attempt to summarize the key advances in this technology.

Narayanan, S.R.; Chun, W.; Valdez, T.I. [California Institute of Technology, Pasadena, CA (United States)] [and others

1996-12-31T23:59:59.000Z

198

Low Voltage High-SNR Pipeline Data Converters Charles Myers, Jipeng Li, Dong-Young Chang, and Un-Ku Moon  

E-Print Network [OSTI]

Low Voltage High-SNR Pipeline Data Converters Charles Myers, Jipeng Li, Dong-Young Chang, and Un pipeline data converter. This is accomplished with the removal of the S/H input stage and the use of a rail limitations. In pipeline data converters, noise reduction options such as oversampling and noise shaping

Moon, Un-Ku

199

Integrating a Feature Selection Algorithm for Classification of Voltage Sags Originated in Transmission and Distribution Networks  

Science Journals Connector (OSTI)

As a global problem in the power quality area, voltage sags are matter of high interest for both utilities and customers. With a view to resolving the problem of sag source location in the power network, this paper introduces a new method based on dimension ... Keywords: Direction, Hybrid Method, Mpca, Voltage Sag

Abbas Khosravi; Toni Martinez; Joaquim Melendez; Joan Colomer; Jorge Sanchez

2007-06-01T23:59:59.000Z

200

LM193/LM293/LM393/LM2903 Low Power Low Offset Voltage Dual Comparators  

E-Print Network [OSTI]

LM193/LM293/LM393/LM2903 Low Power Low Offset Voltage Dual Comparators General Description The LM clock timers; multivibrators and high voltage digital logic gates. The LM193 series was designed to directly interface with TTL and CMOS. When operated from both plus and minus power supplies, the LM193

Lanterman, Aaron

Note: This page contains sample records for the topic "high voltage direct" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

VOLTAGE COLLAPSE AND TRANSIENT ENERGY FUNCTION ANALYSES OF AC/DC SYSTEMS  

E-Print Network [OSTI]

for power system dynamic models, including a third order representation of high voltage direct current (HVDC power limits, HVDC firing angle limits and voltage dependent current order limits (VDCOL) are shown the derivation of individual component Lyapunov functions for simplified models of HVDC links connected

Cañizares, Claudio A.

202

Effect of the change in the load resistance on the high voltage pulse transformer of the intense electron-beam accelerators  

SciTech Connect (OSTI)

A high voltage pulse transformer (HVPT) is usually used as a charging device for the pulse forming line (PFL) of intense electron-beam accelerators (IEBAs). Insulation of the HVPT is one of the important factors that restrict the development of the HVPT. Until now, considerable effort has been focused on minimizing high field regions to avoid insulation breakdown between windings. Characteristics of the HVPT have been widely discussed to achieve these goals, but the effects of the PFL and load resistance on HVPT are usually neglected. In this paper, a HVPT is used as a charging device for the PFL of an IEBA and the effect of the change in the load resistance on the HVPT of the IEBA is presented. When the load resistance does not match the wave impedance of the PFL, a high-frequency bipolar oscillating voltage will occur, and the amplitude of the oscillating voltage will increase with the decrease in the load resistance. The load resistance approximates to zero and the amplitude of the oscillating voltage is much higher. This makes it easier for surface flashover along the insulation materials to form and decrease the lifetime of the HVPT.

Cheng Xinbing; Liu Jinliang; Qian Baoliang; Zhang Yu; Zhang Hongbo [College of Photoelectrical Science and Engineering, National University of Defense Technology, Hunan 410073 (China)

2009-11-15T23:59:59.000Z

203

Low-voltage gyrotrons  

SciTech Connect (OSTI)

For a long time, the gyrotrons were primarily developed for electron cyclotron heating and current drive of plasmas in controlled fusion reactors where a multi-megawatt, quasi-continuous millimeter-wave power is required. In addition to this important application, there are other applications (and their number increases with time) which do not require a very high power level, but such issues as the ability to operate at low voltages and have compact devices are very important. For example, gyrotrons are of interest for a dynamic nuclear polarization, which improves the sensitivity of the nuclear magnetic resonance spectroscopy. In this paper, some issues important for operation of gyrotrons driven by low-voltage electron beams are analyzed. An emphasis is made on the efficiency of low-voltage gyrotron operation at the fundamental and higher cyclotron harmonics. These efficiencies calculated with the account for ohmic losses were, first, determined in the framework of the generalized gyrotron theory based on the cold-cavity approximation. Then, more accurate, self-consistent calculations for the fundamental and second harmonic low-voltage sub-THz gyrotron designs were carried out. Results of these calculations are presented and discussed. It is shown that operation of the fundamental and second harmonic gyrotrons with noticeable efficiencies is possible even at voltages as low as 5-10 kV. Even the third harmonic gyrotrons can operate at voltages about 15 kV, albeit with rather low efficiency (1%-2% in the submillimeter wavelength region).

Glyavin, M. Yu.; Zavolskiy, N. A.; Sedov, A. S. [Institute of Applied Physics RAS, N. Novgorod 603600 (Russian Federation); Nusinovich, G. S. [IREAP, University of Maryland, College Park, Maryland 20742-3511 (United States)

2013-03-15T23:59:59.000Z

204

A wide bandgap silicon carbide (SiC) gate driver for high-temperature and high-voltage applications  

SciTech Connect (OSTI)

Limitations of silicon (Si) based power electronic devices can be overcome with Silicon Carbide (SiC) because of its remarkable material properties. SiC is a wide bandgap semiconductor material with larger bandgap, lower leakage currents, higher breakdown electric field, and higher thermal conductivity, which promotes higher switching frequencies for high power applications, higher temperature operation, and results in higher power density devices relative to Si [1]. The proposed work is focused on design of a SiC gate driver to drive a SiC power MOSFET, on a Cree SiC process, with rise/fall times (less than 100 ns) suitable for 500 kHz to 1 MHz switching frequency applications. A process optimized gate driver topology design which is significantly different from generic Si circuit design is proposed. The ultimate goal of the project is to integrate this gate driver into a Toyota Prius plug-in hybrid electric vehicle (PHEV) charger module. The application of this high frequency charger will result in lighter, smaller, cheaper, and a more efficient power electronics system.

Lamichhane, Ranjan [University of Arkansas; Ericson, Milton Nance [ORNL; Frank, Steven Shane [ORNL; BRITTONJr., CHARLES L. [Oak Ridge National Laboratory (ORNL); Marlino, Laura D [ORNL; Mantooth, Alan [University of Arkansas; Francis, Matt [APEI, Inc.; Shepherd, Dr. Paul [University of Arkansas; Glover, Dr. Michael [University of Arkansas; Podar, Mircea [ORNL; Perez, M [University of Arkansas; Mcnutt, Tyler [APEI, Inc.; Whitaker, Mr. Bret [APEI, Inc.; Cole, Mr. Zach [APEI, Inc.

2014-01-01T23:59:59.000Z

205

Researchers map atomic movements that trigger voltage fade in...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

map atomic movements that trigger voltage fade in high-energy-density batteries January 22, 2015 Voltage and capacity curves from an LMR-NMC high-energy cathode show voltage fade...

206

Voltage controlled current source  

DOE Patents [OSTI]

A seven decade, voltage controlled current source is described for use in testing intermediate range nuclear instruments that covers the entire test current range of from 10 picoamperes to 100 microamperes. High accuracy is obtained throughout the entire seven decades of output current with circuitry that includes a coordinated switching scheme responsive to the input signal from a hybrid computer to control the input voltage to an antilog amplifier, and to selectively connect a resistance to the antilog amplifier output to provide a continuous output current source as a function of a preset range of input voltage. An operator controlled switch provides current adjustment for operation in either a real-time simulation test mode or a time response test mode.

Casne, Gregory M. (Pittsburgh, PA)

1992-01-01T23:59:59.000Z

207

High performance computing: Clusters, constellations, MPPs, and future directions  

E-Print Network [OSTI]

and Jim Gray, “High Performance Computing: Crays, Clusters,The Marketplace of High-Performance Computing”, ParallelHigh Performance Computing Clusters, Constellations, MPPs,

Dongarra, Jack; Sterling, Thomas; Simon, Horst; Strohmaier, Erich

2003-01-01T23:59:59.000Z

208

A High Temperature Direct Vehicle Exhaust Flowmeter for Heavy...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Directions in Engine-Efficiency and Emissions Research (DEER) Conference in Detroit, MI, September 27-30, 2010. p-08nevius.pdf More Documents & Publications Complex System...

209

Energy-Efficient Melting and Direct Delivery of High Quality...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

preparing and melting the metal off-site using efficient electric Direct Immersion (DI) heat- ers, then transporting the molten metal in Transportable Electric Ladle (TEL) trucks...

210

Identifying surface structural changes in layered Li-excess nickel manganese oxides in high voltage lithium ion batteries: A joint experimental and theoretical study  

SciTech Connect (OSTI)

High voltage cathode materials Li-excess layered oxide compounds Li[Ni{sub x}Li{sub 1/3-2x/3}Mn{sub 2/3-x/3}]O{sub 2} (0 < x < 1/2) are investigated in a joint study combining both computational and experimental methods. The bulk and surface structures of pristine and cycled samples of Li[Ni{sub 1/5}Li{sub 1/5}Mn{sub 3/5}]O{sub 2} are characterized by synchrotron X-Ray diffraction together with aberration corrected Scanning Transmission Electron Microscopy (a-S/TEM). Electron Energy Loss Spectroscopy (EELS) is carried out to investigate the surface changes of the samples before/after electrochemical cycling. Combining first principles computational investigation with our experimental observations, a detailed lithium de-intercalation mechanism is proposed for this family of Li-excess layered oxides. The most striking characteristics in these high voltage high energy density cathode materials are (1) formation of tetrahedral lithium ions at voltage less than 4.45 V and (2) the transition metal (TM) ions migration leading to phase transformation on the surface of the materials. We show clear evidence of a new spinel-like solid phase formed on the surface of the electrode materials after high-voltage cycling. It is proposed that such surface phase transformation is one of the factors contributing to the first cycle irreversible capacity and the main reason for the intrinsic poor rate capability of these materials.

Xu, Bo; Fell, Christopher R.; Chi, Miaofang; Meng, Ying Shirley (ORNL); (Florida); (UCSD)

2011-09-06T23:59:59.000Z

211

A PC-PCL-based control system for the high-voltage pulsed-power operation of the Intense Diagnostic Neutral Beam (IDNB) Experiment  

SciTech Connect (OSTI)

A stand-alone, semiautomated control system for the high-voltage pulsed-power energy sources on the Intense Diagnostic Neutral Beam Experiment at Los Alamos National Laboratory using personal computer (PC) and programmable logic controller (PLC) technology has been developed and implemented. The control system, consisting of a PC with the graphic operator interface, the network connecting the PC to the PLC, the PLC, the PLC I/O modules, fiber-optic interfaces and software, is described.

Gribble, R.

1993-06-01T23:59:59.000Z

212

High Efficiency Direct Carbon and Hydrogen Fuel Cells for Fossil Fuel Power Generation  

SciTech Connect (OSTI)

Hydrogen he1 cells have been under development for a number of years and are now nearing commercial applications. Direct carbon fuel cells, heretofore, have not reached practical stages of development because of problems in fuel reactivity and cell configuration. The carbon/air fuel cell reaction (C + O{sub 2} = CO{sub 2}) has the advantage of having a nearly zero entropy change. This allows a theoretical efficiency of 100 % at 700-800 C. The activities of the C fuel and CO{sub 2} product do not change during consumption of the fuel. Consequently, the EMF is invariant; this raises the possibility of 100% fuel utilization in a single pass. (In contrast, the high-temperature hydrogen fuel cell has a theoretical efficiency of and changes in fuel activity limit practical utilizations to 75-85%.) A direct carbon fuel cell is currently being developed that utilizes reactive carbon particulates wetted by a molten carbonate electrolyte. Pure COZ is evolved at the anode and oxygen from air is consumed at the cathode. Electrochemical data is reported here for the carbon/air cell utilizing carbons derived from he1 oil pyrolysis, purified coal, purified bio-char and petroleum coke. At 800 O C, a voltage efficiency of 80% was measured at power densities of 0.5-1 kW/m2. Carbon and hydrogen fuels may be produced simultaneously at lugh efficiency from: (1) natural gas, by thermal decomposition, (2) petroleum, by coking or pyrolysis of distillates, (3) coal, by sequential hydrogasification to methane and thermal pyrolysis of the methane, with recycle of the hydrogen, and (4) biomass, similarly by sequential hydrogenation and thermal pyrolysis. Fuel production data may be combined with direct C and H2 fuel cell operating data for power cycle estimates. Thermal to electric efficiencies indicate 80% HHV [85% LHV] for petroleum, 75.5% HHV [83.4% LHV] for natural gas and 68.3% HHV [70.8% LHV] for lignite coal. Possible benefits of integrated carbon and hydrogen fuel cell power generation cycles are: (1) increased efficiency by a factor of up to 2 over many conventional fossil fuel steam plants, (2) reduced power generation cost, especially for increasing fossil fuel cost, (3) reduced CO2 emission per kWh, and (4) direct sequestration or reuse (e.g., in enhanced oil or NG recovery) of the CO{sub 2} product.

Steinberg, M; Cooper, J F; Cherepy, N

2002-01-02T23:59:59.000Z

213

Voltage balanced multilevel voltage source converter system  

DOE Patents [OSTI]

A voltage balanced multilevel converter for high power AC applications such as adjustable speed motor drives and back-to-back DC intertie of adjacent power systems. This converter provides a multilevel rectifier, a multilevel inverter, and a DC link between the rectifier and the inverter allowing voltage balancing between each of the voltage levels within the multilevel converter. The rectifier is equipped with at least one phase leg and a source input node for each of the phases. The rectifier is further equipped with a plurality of rectifier DC output nodes. The inverter is equipped with at least one phase leg and a load output node for each of the phases. The inverter is further equipped with a plurality of inverter DC input nodes. The DC link is equipped with a plurality of rectifier charging means and a plurality of inverter discharging means. The plurality of rectifier charging means are connected in series with one of the rectifier charging means disposed between and connected in an operable relationship with each adjacent pair of rectifier DC output nodes. The plurality of inverter discharging means are connected in series with one of the inverter discharging means disposed between and connected in an operable relationship with each adjacent pair of inverter DC input nodes. Each of said rectifier DC output nodes are individually electrically connected to the respective inverter DC input nodes. By this means, each of the rectifier DC output nodes and each of the inverter DC input nodes are voltage balanced by the respective charging and discharging of the rectifier charging means and the inverter discharging means.

Peng, Fang Zheng (Oak Ridge, TN); Lai, Jih-Sheng (Knoxville, TN)

1997-01-01T23:59:59.000Z

214

Voltage balanced multilevel voltage source converter system  

DOE Patents [OSTI]

Disclosed is a voltage balanced multilevel converter for high power AC applications such as adjustable speed motor drives and back-to-back DC intertie of adjacent power systems. This converter provides a multilevel rectifier, a multilevel inverter, and a DC link between the rectifier and the inverter allowing voltage balancing between each of the voltage levels within the multilevel converter. The rectifier is equipped with at least one phase leg and a source input node for each of the phases. The rectifier is further equipped with a plurality of rectifier DC output nodes. The inverter is equipped with at least one phase leg and a load output node for each of the phases. The inverter is further equipped with a plurality of inverter DC input nodes. The DC link is equipped with a plurality of rectifier charging means and a plurality of inverter discharging means. The plurality of rectifier charging means are connected in series with one of the rectifier charging means disposed between and connected in an operable relationship with each adjacent pair of rectifier DC output nodes. The plurality of inverter discharging means are connected in series with one of the inverter discharging means disposed between and connected in an operable relationship with each adjacent pair of inverter DC input nodes. Each of said rectifier DC output nodes are individually electrically connected to the respective inverter DC input nodes. By this means, each of the rectifier DC output nodes and each of the inverter DC input nodes are voltage balanced by the respective charging and discharging of the rectifier charging means and the inverter discharging means. 15 figs.

Peng, F.Z.; Lai, J.S.

1997-07-01T23:59:59.000Z

215

Silicon-on-insulator-based high-voltage, high-temperature integrated circuit gate driver for silicon carbide-based power field effect transistors  

SciTech Connect (OSTI)

Silicon carbide (SiC)-based field effect transistors (FETs) are gaining popularity as switching elements in power electronic circuits designed for high-temperature environments like hybrid electric vehicle, aircraft, well logging, geothermal power generation etc. Like any other power switches, SiC-based power devices also need gate driver circuits to interface them with the logic units. The placement of the gate driver circuit next to the power switch is optimal for minimising system complexity. Successful operation of the gate driver circuit in a harsh environment, especially with minimal or no heat sink and without liquid cooling, can increase the power-to-volume ratio as well as the power-to-weight ratio for power conversion modules such as a DC-DC converter, inverter etc. A silicon-on-insulator (SOI)-based high-voltage, high-temperature integrated circuit (IC) gate driver for SiC power FETs has been designed and fabricated using a commercially available 0.8--m, 2-poly and 3-metal bipolar-complementary metal oxide semiconductor (CMOS)-double diffused metal oxide semiconductor (DMOS) process. The prototype circuit-s maximum gate drive supply can be 40-V with peak 2.3-A sourcing/sinking current driving capability. Owing to the wide driving range, this gate driver IC can be used to drive a wide variety of SiC FET switches (both normally OFF metal oxide semiconductor field effect transistor (MOSFET) and normally ON junction field effect transistor (JFET)). The switching frequency is 20-kHz and the duty cycle can be varied from 0 to 100-. The circuit has been successfully tested with SiC power MOSFETs and JFETs without any heat sink and cooling mechanism. During these tests, SiC switches were kept at room temperature and ambient temperature of the driver circuit was increased to 200-C. The circuit underwent numerous temperature cycles with negligible performance degradation.

Tolbert, Leon M [ORNL; Huque, Mohammad A [ORNL; Blalock, Benjamin J [ORNL; Islam, Syed K [ORNL

2010-01-01T23:59:59.000Z

216

Direct  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

interactions, and the pollutant emission is hence directly proportional to the bulk neutral density. Simultaneously monitoring the total emission at 1040 nm and the...

217

Pulsed CO{sub 2} laser with an X-ray preioniser based on a high-voltage low-pressure glow discharge  

SciTech Connect (OSTI)

An X-ray preioniser with an electron beam energy density of 0.1 J cm{sup -2} based on a high-voltage (20 - 40 kV) low-pressure glow discharge is developed for repetitively pulsed gas lasers. The electron concentration in the CO{sub 2} - N{sub 2} - He mixture as a function of the voltage across the preioniser is calculated for titanium and other foils. The preioniser can be operated both in a single-pulse regime and at pulse repetition rates ranging up to hundreds of Hertz. A specific energy yield of 51 J L{sup -1} is achieved in the X-ray preionised pulsed CO{sub 2} atmospheric-pressure laser. This preioniser was shown to be efficient for other active media (CO and excimer lasers), which opens up new opportunities for the development of repetitively pulsed gas lasers. (lasers)

Oreshkin, V F; Seregin, Aleksandr M; Sinaiskii, V V; Shchetinkina, T A ['Astrofizika' Research and Production Association (Russian Federation); Sorokin, A R [Institute of Semiconductor Physics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk (Russian Federation)

2003-12-31T23:59:59.000Z

218

Optimal Voltage Control of the Southern Norwegian Power Grid.  

E-Print Network [OSTI]

??This thesis contains the synthesis, analysis and simulation results of an automatic optimal voltage controller for the Southern Norwegian power grid. Currently the high voltage… (more)

Hannisdal, Erik Lundegaard

2011-01-01T23:59:59.000Z

219

> REPLACE THIS LINE WITH YOUR PAPER IDENTIFICATION NUMBER (DOUBLE-CLICK HERE TO EDIT) < 1 Abstract--In high current, high voltage, high temperature  

E-Print Network [OSTI]

and high current applications, such as HVDC transmission [1] or pulsed power application [2], a thyristor

Paris-Sud XI, Université de

220

DIRECT NUMERICAL SIMULATION OF HOT AND HIGHLY PULSATED  

E-Print Network [OSTI]

. We focus here on situations where plasma jets are randomly forced by an electric arc resulting pulsated jet flows at 12 000 K developing in a colder environment. Such flows are used to model plasma jets generated by direct current plasma torch. Plasma spraying is used to deposit thick coatings on a substrate

Sart, Remi

Note: This page contains sample records for the topic "high voltage direct" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

High-Affinity Binding and Direct Electron Transfer to Solid Metals...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Binding and Direct Electron Transfer to Solid Metals by the Shewanella oneidensis MR-1 Outer Membrane c-type High-Affinity Binding and Direct Electron Transfer to Solid Metals...

222

Method and apparatus for high-efficiency direct contact condensation  

DOE Patents [OSTI]

A direct contact condenser having a downward vapor flow chamber and an upward vapor flow chamber, wherein each of the vapor flow chambers includes a plurality of cooling liquid supplying pipes and a vapor-liquid contact medium disposed thereunder to facilitate contact and direct heat exchange between the vapor and cooling liquid. The contact medium includes a plurality of sheets arranged to form vertical interleaved channels or passageways for the vapor and cooling liquid streams. The upward vapor flow chamber also includes a second set of cooling liquid supplying pipes disposed beneath the vapor-liquid contact medium which operate intermittently in response to a pressure differential within the upward vapor flow chamber. The condenser further includes separate wells for collecting condensate and cooling liquid from each of the vapor flow chambers. In alternate embodiments, the condenser includes a cross-current flow chamber and an upward flow chamber, a plurality of upward flow chambers, or a single upward flow chamber. The method of use of the direct contact condenser of this invention includes passing a vapor stream sequentially through the downward and upward vapor flow chambers, where the vapor is condensed as a result of heat exchange with the cooling liquid in the contact medium. The concentration of noncondensable gases in the resulting condensate-liquid mixtures can be minimized by controlling the partial pressure of the vapor, which depends in part upon the geometry of the vapor-liquid contact medium. In another aspect of this invention, the physical and chemical performance of a direct contact condenser can be predicted based on the vapor and coolant compositions, the condensation conditions. and the geometric properties of the contact medium.

Bharathan, Desikan (Lakewood, CO); Parent, Yves (Golden, CO); Hassani, A. Vahab (Golden, CO)

1999-01-01T23:59:59.000Z

223

Method and apparatus for high-efficiency direct contact condensation  

DOE Patents [OSTI]

A direct contact condenser having a downward vapor flow chamber and an upward vapor flow chamber, wherein each of the vapor flow chambers includes a plurality of cooling liquid supplying pipes and a vapor-liquid contact medium disposed thereunder to facilitate contact and direct heat exchange between the vapor and cooling liquid. The contact medium includes a plurality of sheets arranged to form vertical interleaved channels or passageways for the vapor and cooling liquid streams. The upward vapor flow chamber also includes a second set of cooling liquid supplying pipes disposed beneath the vapor-liquid contact medium which operate intermittently in response to a pressure differential within the upward vapor flow chamber. The condenser further includes separate wells for collecting condensate and cooling liquid from each of the vapor flow chambers. In alternate embodiments, the condenser includes a cross-current flow chamber and an upward flow chamber, a plurality of upward flow chambers, or a single upward flow chamber. The method of use of the direct contact condenser of this invention includes passing a vapor stream sequentially through the downward and upward vapor flow chambers, where the vapor is condensed as a result of heat exchange with the cooling liquid in the contact medium. The concentration of noncondensable gases in the resulting condensate-liquid mixtures can be minimized by controlling the partial pressure of the vapor, which depends in part upon the geometry of the vapor-liquid contact medium. In another aspect of this invention, the physical and chemical performance of a direct contact condenser can be predicted based on the vapor and coolant compositions, the condensation conditions, and the geometric properties of the contact medium. 39 figs.

Bharathan, D.; Parent, Y.; Hassani, A.V.

1999-07-20T23:59:59.000Z

224

High performance organic field-effect transistors with ultra-thin HfO{sub 2} gate insulator deposited directly onto the organic semiconductor  

SciTech Connect (OSTI)

We have produced stable organic field-effect transistors (OFETs) with an ultra-thin HfO{sub 2} gate insulator deposited directly on top of rubrene single crystals by atomic layer deposition (ALD). We find that ALD is a gentle deposition process to grow thin films without damaging rubrene single crystals, as results these devices have a negligibly small threshold voltage and are very stable against gate-bias-stress, and the mobility exceeds 1 cm{sup 2}/V s. Moreover, the devices show very little degradation even when kept in air for more than 2 months. These results demonstrate thin HfO{sub 2} layers deposited by ALD to be well suited as high capacitance gate dielectrics in OFETs operating at small gate voltage. In addition, the dielectric layer acts as an effective passivation layer to protect the organic semiconductor.

Ono, S., E-mail: shimpei@criepi.denken.or.jp [Central Research Institute of Electric Power Industry, Komae, Tokyo 201-8511 (Japan); Häusermann, R. [Central Research Institute of Electric Power Industry, Komae, Tokyo 201-8511 (Japan) [Central Research Institute of Electric Power Industry, Komae, Tokyo 201-8511 (Japan); Laboratory for Solid State Physics, ETH Zurich, Zurich 8093 (Switzerland); Chiba, D. [Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan) [Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho Kawaguchi, Saitama 322-0012 (Japan); Department of Applied Physics, University of Tokyo, Tokyo 113-8656 (Japan); Shimamura, K.; Ono, T. [Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan)] [Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); Batlogg, B. [Laboratory for Solid State Physics, ETH Zurich, Zurich 8093 (Switzerland)] [Laboratory for Solid State Physics, ETH Zurich, Zurich 8093 (Switzerland)

2014-01-06T23:59:59.000Z

225

High specific power, direct methanol fuel cell stack  

DOE Patents [OSTI]

The present invention is a fuel cell stack including at least one direct methanol fuel cell. A cathode manifold is used to convey ambient air to each fuel cell, and an anode manifold is used to convey liquid methanol fuel to each fuel cell. Tie-bolt penetrations and tie-bolts are spaced evenly around the perimeter to hold the fuel cell stack together. Each fuel cell uses two graphite-based plates. One plate includes a cathode active area that is defined by serpentine channels connecting the inlet manifold with an integral flow restrictor to the outlet manifold. The other plate includes an anode active area defined by serpentine channels connecting the inlet and outlet of the anode manifold. Located between the two plates is the fuel cell active region.

Ramsey, John C. (Los Alamos, NM); Wilson, Mahlon S. (Los Alamos, NM)

2007-05-08T23:59:59.000Z

226

Direct power control of shunt active filter using high selectivity filter (HSF) under distorted or unbalanced conditions  

E-Print Network [OSTI]

.A. Djaffar) Abstract This paper describes the design of a new configuration of direct power control (DPC inverter voltage vector in order to minimize instantaneous active and reactive power errors using two powers by selecting the optimal switching states of the inverter. Simulation results have proved

Paris-Sud XI, Université de

227

Direct calculation of leak path factors for highly compartmentalized buildings  

SciTech Connect (OSTI)

The large, highly compartmentalized configurations of buildings at many Department of Energy (DOE) facilities call the validity of traditional, simplistic methods for estimating contaminant leak path factors (LPFs) into question. Conversely, rigorous calculation of LPFs using detailed flow-field analysis computer codes is impractical for routine analysis. This paper describes a recent application of a rigorous, yet practical, method of calculating LPFs for the Chemical and Metallurgical Research (CMR) Facility at Los Alamos National Laboratory (LANL). The approach involves computer simulation of airborne contaminant transport using the MELCOR computer code. MELCOR is a general-purpose, fluid flow and aerosol transport analysis code originally developed by the US Nuclear Regulatory Commission to evaluate the release, transport, and deposition of radionuclides in nuclear reactor systems. However, the fundamental mathematical models in the code and the modular code architecture make it suitable to the CMR analysis.

Leonard, M.T. [ITS Corp., Albuquerque, NM (United States); McClure, P.R. [Los Alamos National Lab., NM (United States)

1998-12-01T23:59:59.000Z

228

Premixed direct injection nozzle for highly reactive fuels  

DOE Patents [OSTI]

A fuel/air mixing tube for use in a fuel/air mixing tube bundle is provided. The fuel/air mixing tube includes an outer tube wall extending axially along a tube axis between an inlet end and an exit end, the outer tube wall having a thickness extending between an inner tube surface having a inner diameter and an outer tube surface having an outer tube diameter. The tube further includes at least one fuel injection hole having a fuel injection hole diameter extending through the outer tube wall, the fuel injection hole having an injection angle relative to the tube axis. The invention provides good fuel air mixing with low combustion generated NOx and low flow pressure loss translating to a high gas turbine efficiency, that is durable, and resistant to flame holding and flash back.

Ziminsky, Willy Steve; Johnson, Thomas Edward; Lacy, Benjamin Paul; York, William David; Uhm, Jong Ho; Zuo, Baifang

2013-09-24T23:59:59.000Z

229

Peculiarities of the current-voltage characteristics of a Josephson medium in a YBCO high-temperature superconductor  

Science Journals Connector (OSTI)

The influence of a weak magnetic field (H high-temperature superconductor (HTSC) near the superconducting transitio...

M. A. Vasyutin

2013-12-01T23:59:59.000Z

230

Measurement of critical energy for direct initiation of spherical detonations in stoichiometric high-pressure H{sub 2}-O{sub 2} mixtures  

SciTech Connect (OSTI)

In this study, the critical energy for direct initiation of spherical detonations in stoichiometric high-pressure hydrogen-oxygen mixtures are measured and investigated to look at the effect of explosion limits on the detonation sensitivity. Results up to an initial pressure of 20 atm are obtained. Experiments are carried out in a spherical bomb and direct initiation is achieved via spark ignition from a high-voltage capacitor discharge. A detailed description of different methods to obtain a good estimate of the correct amount of energy deposited into the mixture used to initiate the detonation, including the calorimeter method and current method, is provided. It is demonstrated that at elevated initial pressure, the second explosion limit effect plays a significant role leading to slow-branching reactions and the detonation sensitivity of hydrogen mixtures is comparable to other common hydrocarbon mixtures at such condition. (author)

Kamenskihs, Vsevolods; Lee, John H.S. [Department of Mechanical Engineering, McGill University, Montreal, Quebec (Canada); Ng, Hoi Dick [Department of Mechanical and Industrial Engineering, Concordia University, Montreal, Quebec (Canada)

2010-09-15T23:59:59.000Z

231

Assessment of research directions for high voltage direct current power systems. Quarterly technical progress report, October 1, 1980-December 31, 1980  

SciTech Connect (OSTI)

Activities during this quarterly period on proposed HVDC systems research are reported. These activities include studies of HVDC converters, computerized simulation of HVDC systems, circuit breakers, and long-range planning of HVDC projects. (LCL)

Long, W F

1981-01-01T23:59:59.000Z

232

Propagation direction reversal of ionization zones in the transition between high and low current magnetron sputtering  

SciTech Connect (OSTI)

Past research has revealed the propagation of dense, asymmetric ionization zones in both high and low current magnetron discharges. Here we report about the direction reversal of ionization zone propagation as observed with fast cameras. At high currents, zones move in the E B direction with velocities of 103 to 104 m/s. However at lower currents, ionization zones are observed to move in the opposite, the -E B direction, with velocities ~;; 103 m/s. It is proposed that the direction reversal is associated with the local balance of ionization and supply of neutrals in the ionization zone.

School of Materials Science and Engineering, State Key Lab for Materials Processing and Die & Mold Technology, Huazhong University of Science and Technology, Wuhan 430074, China; Department of Physics, University of California Berkeley, Berkeley, California 94720, USA; Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, USA; Yang, Yuchen; Liu, Jason; Liu, Lin; Anders, André

2014-12-11T23:59:59.000Z

233

RECIPIENT:Princeton Power Systems STATE: NJ PROJECT Marine High-Voltage Power Conditioning and Transmission System with Integrated Energy Storage  

Broader source: Energy.gov (indexed) [DOE]

Princeton Power Systems Princeton Power Systems STATE: NJ PROJECT Marine High-Voltage Power Conditioning and Transmission System with Integrated Energy Storage TITLE: Funding Opportunity Announcement Number Procurement Instrument Number NEPA Control Number cm Number DE-FOA-0000293 DE-EE0003640 GFO-000364~001 GOO Based on my review of the information concerning the proposed action, as NEPA Compliance Officer (authorized under DOE Order 451.1A), I have made the foUowing determination: CX, EA, EIS APPENDIX AND NUMBER: Description: A9 Information gathering (including, but not limited to, ~terature surveys, inventories, audits), data analysis (including computer modeling), document preparation (such as conceptual design or feasibility studies, analytical energy supply

234

Structure Design and Test Research on the Electrical Properties of High Voltage Instrumentation Cables for the Fusion Reactor  

Science Journals Connector (OSTI)

The HV instrumentation cable is an important route for the signals transmission from the superconducting magnets to the control system, it should be long term operated at around 4.2 K and withstand the high vo...

Qingsheng Gao; Xiongyi Huang; Yuntao Song; Weibin Xi…

2014-08-01T23:59:59.000Z

235

Statistical analysis and optimization of processing parameters in high-power direct diode laser cladding  

Science Journals Connector (OSTI)

High-power direct diode laser (HPDDL) offers a wide laser beam with a top-hat intensity distribution, ... making it an ideal tool for large-area cladding. In this study, a systemic study on the HPDDL cladding pro...

Shuang Liu; Radovan Kovacevic

2014-09-01T23:59:59.000Z

236

Automatic voltage imbalance detector  

DOE Patents [OSTI]

A device for indicating and preventing damage to voltage cells such as galvanic cells and fuel cells connected in series by detecting sequential voltages and comparing these voltages to adjacent voltage cells. The device is implemented by using operational amplifiers and switching circuitry is provided by transistors. The device can be utilized in battery powered electric vehicles to prevent galvanic cell damage and also in series connected fuel cells to prevent fuel cell damage.

Bobbett, Ronald E. (Los Alamos, NM); McCormick, J. Byron (Los Alamos, NM); Kerwin, William J. (Tucson, AZ)

1984-01-01T23:59:59.000Z

237

Dielectric-wall linear accelerator with a high voltage fast rise time switch that includes a pair of electrodes between which are laminated alternating layers of isolated conductors and insulators  

DOE Patents [OSTI]

A dielectric-wall linear accelerator is improved by a high-voltage, fast rise-time switch that includes a pair of electrodes between which are laminated alternating layers of isolated conductors and insulators. A high voltage is placed between the electrodes sufficient to stress the voltage breakdown of the insulator on command. A light trigger, such as a laser, is focused along at least one line along the edge surface of the laminated alternating layers of isolated conductors and insulators extending between the electrodes. The laser is energized to initiate a surface breakdown by a fluence of photons, thus causing the electrical switch to close very promptly. Such insulators and lasers are incorporated in a dielectric wall linear accelerator with Blumlein modules, and phasing is controlled by adjusting the length of fiber optic cables that carry the laser light to the insulator surface. 12 figs.

Caporaso, G.J.; Sampayan, S.E.; Kirbie, H.C.

1998-10-13T23:59:59.000Z

238

High gradient magnetic beneficiation of dry pulverized coal via upwardly directed recirculating fluidization  

DOE Patents [OSTI]

This invention relates to an improved device and method for the high gradient magnetic beneficiation of dry pulverized coal, for the purpose of removing sulfur and ash from the coal whereby the product is a dry environmentally acceptable, low-sulfur fuel. The process involves upwardly directed recirculating air fluidization of selectively sized powdered coal in a separator having sections of increasing diameters in the direction of air flow, with magnetic field and flow rates chosen for optimum separations depending upon particulate size.

Eissenberg, David M. (Oak Ridge, TN); Liu, Yin-An (Opelika, AL)

1980-01-01T23:59:59.000Z

239

Substation voltage upgrading  

SciTech Connect (OSTI)

This report addresses specific issues to support sound yet not unduly conservative uprating practices for substations. The main parts of the report cover the insulation withstand and overvoltage protection aspects, environmental measurements, reliability criteria, and industry experience. First the insulation design concerns are addressed. Substation stress by a backflashover of the line insulation due to lightning in the vicinity of the substation is recognized as a critical stress. A representative part of a 550 kV BIL substation was erected at the EPRI High Voltage Transmission Research Center, where also a special test circuit was assembled to produce a fast front, slow tail (0.2/200 {mu}s) wave. The substation as well as some special configurations were tested for line-to-ground and line-to-line withstand. Computer studies were performed to complement the test results. A number of important conclusions was reached. The most prominent result in that the high frequency oscillations, as caused by reflections within the substation, do not effect the Critical Flashover Voltage (CFO). The present practice, based on the highest peak is therefore very conservative. The slow tail of the wave appears to dictate the CFO. An arrester model for computer studies to represent very fast as well as slow phenomena was derived. It is based on full scale arrester test data, made available in this project. The computer program to calculate arrester model parameters is also a part of the report. The electric environmental measurements are reported for the tested substation at the HVTRC and for the uprated substation of Public Service Company of Colorado, both before and after the uprating. The performance is satisfactory when corona free hardware is used. Insulation design criteria are analyzed based on substation reliability, the system viewpoint and consequences of the failure. Utility experience with uprated substations is reviewed.

Panek, J.; Elahi, H.; Lux, A.; Imece, A.F. (General Electric Co., Schenectady, NY (United States). Power Systems Engineering Dept.); LaPanse, R.A.; Stewart, J.R. (Public Service Co. of Colorado, Denver, CO (United States))

1992-04-01T23:59:59.000Z

240

High-Voltage Test Laboratories  

Science Journals Connector (OSTI)

The power for a complete HV laboratory is usually supplied from a medium-...9.20...). One or several three-phase distribution transformers in a nearby substation should be used for that purpose. Their...Sect. 9.2...

Wolfgang Hauschild; Eberhard Lemke

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage direct" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Classification of Voltage Sags Based on MPCA Models  

Science Journals Connector (OSTI)

In this paper, we introduce a new framework for classification of short duration voltage reductions in the area of Power Quality Monitoring using Multiway Principal Component Analysis (MPCA). Firstly, we recast the sags occurred in High Voltage (HV) ...

Abbas Khosravi; Joaquim Melendez; Joan Colomer

2007-06-01T23:59:59.000Z

242

Modulated voltage metastable ionization detector  

SciTech Connect (OSTI)

Metastable ionization detectors used for chromatographic analysis usually employa fixed high voltage for the ionization potential. For this reason, the operating range is limited to about three orders of magnitude. By use of the technique disclosed in the instant invention, operating ranges of about nine orders of magnitude are obtained. The output current from a metastable ionization detector (MID) is applied to a modulation voltage circuit. An adjustment is made to balance out the background current, and an output current, above background, is applied to an input of a strip chart recorder. For low level concentrations, i.e., low detected output current, the ionization potential will be at a maximum and the metastable ionization detector will operate at its most sensitive level. When the detected current from the metastable ionization detector increases above a predetermined threshold level, a voltage control circuit is activated which turns on a high voltage transistor which acts to reduce the ionization potential. The ionization potential applied to the metastable ionization detector is then varied so as to maintain the detected signal level constant. The variation in ionization potential is now related to the concentration fo the constituent and a representative amplitude is applied to another input of said strip chart recorder.

Carle, G. C.; Humphry, D. E.; Kojiro, D. R.

1985-08-27T23:59:59.000Z

243

Constant voltage electro-slag remelting control  

DOE Patents [OSTI]

A system for controlling electrode gap in an electro-slag remelt furnace has a constant regulated voltage and an electrode which is fed into the slag pool at a constant rate. The impedance of the circuit through the slag pool is directly proportional to the gap distance. Because of the constant voltage, the system current changes are inversely proportional to changes in gap. This negative feedback causes the gap to remain stable. 1 fig.

Schlienger, M.E.

1996-10-22T23:59:59.000Z

244

Vehicle Technologies Office Merit Review 2014: High Energy Density Li-ion Cells for EV’s Based on Novel, High Voltage Cathode Material Systems  

Broader source: Energy.gov [DOE]

Presentation given by Farasis Energy, Inc. at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about high energy density Li...

245

Strong enhancement of light absorption and highly directive thermal emission in graphene  

E-Print Network [OSTI]

Strong enhancement of light absorption and highly directive thermal emission in graphene Mingbo Pu: Graphene is a two-dimensional material with exotic electronic, optical and thermal properties. The optical absorption in monolayer graphene is limited by the fine structure constant . Here we demonstrated the strong

Chen, Po

246

High-Efficiency Dry Reforming of Biomethane Directly Using Pulsed Electric Discharge at Ambient Condition  

Science Journals Connector (OSTI)

High-Efficiency Dry Reforming of Biomethane Directly Using Pulsed Electric Discharge at Ambient Condition ... Biomethane is produced by the fermentation of biomass-derived organic waste, such as waste from stock breeding. ... From the viewpoint of better energy use, biomethane, which is a kind of biomass, is an efficient energy source. ...

Yasushi Sekine; Junya Yamadera; Shigeru Kado; Masahiko Matsukata; Eiichi Kikuchi

2007-12-12T23:59:59.000Z

247

Low Voltage Electrostatic Actuation and Displacement Measurement through Resonant Drive Circuit.  

E-Print Network [OSTI]

??An electrostatic actuator driven by conventional voltage control and charge control requires high actuation voltage and suffers from the pull-in phenomenon that limits its operation… (more)

Park, Sangtak

2011-01-01T23:59:59.000Z

248

High-speed one-dimensional spatial light modulator for Laser Direct Imaging and other patterning applications  

E-Print Network [OSTI]

High-speed one-dimensional spatial light modulator for Laser Direct Imaging and other patterning developed a one-dimensional high-speed spatial light modulator in cooperation with Micronic Mydata AB of ultraviolet light needs to be combined with high throughput and high precision. Keywords: Laser Direct Imaging

Jonsson, Fredrik

249

Research to Prevent the Anti-charging Incident of the Voltage Transformer in the Substation  

Science Journals Connector (OSTI)

The voltage transformer of the power system is a device which converts the high voltage of the primary side into the low voltage required by secondary device, and the primary side connects to the primary syste...

Hui-Ying Chen; Zhi-Peng Wang; Mu-Qin Tian

2011-01-01T23:59:59.000Z

250

A high-contrast coronagraph for earth-like exoplanet direct imaging: design and test  

E-Print Network [OSTI]

The high-contrast coronagraph for direct imaging earth-like exoplanet at the visible needs a contrast of 10^(-10) at a small angular separation of 4 lambda/D or less. Here we report our recent laboratory experiment that is close to the limits. The test of the high-contrast imaging coronagraph is based on our step-transmission apodized filter. To achieve the goal, we use a liquid crystal array (LCA) as a phase corrector to create a dark hole based on our dedicated focal dark algorithm. We have suppressed the diffracted and speckle noise near the star point image to a level of 1.68 x 10^(-9) at 4 lambda/D, which can be immediately used for the direct imaging of Jupiter like exoplanets. This demonstrates that high-contrast coronagraph telescope in space has the potentiality to detect and characterize earth-like planets.

Liu, C C; Dou, J P; Zhu, Y T; Zhang, X; Zhao, G; Wu, Zh; Chen, R

2014-01-01T23:59:59.000Z

251

Constant voltage ultracapacitor  

Science Journals Connector (OSTI)

Ultracapacitors have attracted lots of attention recently due to their growing use in hybrid vehicles and in energy storage applications for the smart grid. A very undesirable feature of ultracapacitors is the fact that the voltage drops as the capacitor is discharged. DC-DC converters are employed at present to convert the voltage of the ultracapacitor to constant voltage; however these converters typically do not operate if the voltage of the ultracapacitor drops below 1?V. In addition DC-DC converters suffer from well-known size/efficiency tradeoffs. This paper introduces a novel new ultracapacitor that is characterized by constant voltage. The new ultracapacitor does not utilize familiar energy conversion principles. Rather operation depends on an embedded electromechanical system that actually alters the capacitance of the ultracapacitor as the device is discharged. Due to a simple proportionality relationship between charge capacitance and voltage the voltage remains constant. Theoretical and experimental investigations have shown that the embedded mechanism for altering the capacitance has an efficiency of 99% or higher.

Ezzat G. Bakhoum

2012-01-01T23:59:59.000Z

252

Substation voltage upgrading  

SciTech Connect (OSTI)

Substation voltage uprating, i.e., conversion of a substation from a lower rated voltage to a higher rated voltage without a complete substation rebuild, can lead to excellent economic benefits. Utilization of the old substation layout and/or the existing equipment, to some extent, is the practical objective of such an uprating. The objective of this project was to assess the opportunities for substation uprating in the industry, to establish feasibility for such uprating and to study methods for accomplishing it. The final aim of the project was to provide guidance to utilities interested in uprating. 56 refs., 41 figs., 18 tabs.

Panek, J.; Elahi, H.; Sublich, M. (General Electric Co., Schenectady, NY (USA). Systems Development and Engineering Dept.)

1989-08-01T23:59:59.000Z

253

High-Temperature Downhole MWD Tools for Directional Drilling | Open Energy  

Open Energy Info (EERE)

MWD Tools for Directional Drilling MWD Tools for Directional Drilling Jump to: navigation, search Geothermal ARRA Funded Projects for High-Temperature Downhole MWD Tools for Directional Drilling Loading map... {"format":"googlemaps3","type":"ROADMAP","types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"limit":200,"offset":0,"link":"all","sort":[""],"order":[],"headers":"show","mainlabel":"","intro":"","outro":"","searchlabel":"\u2026 further results","default":"","geoservice":"google","zoom":false,"width":"600px","height":"350px","centre":false,"layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","icon":"","visitedicon":"","forceshow":true,"showtitle":true,"hidenamespace":false,"template":false,"title":"","label":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"locations":[{"text":"

254

Phase Transitions and High-Voltage Electrochemical Behavior of LiCoO2 Thin Films Grown by Pulsed Laser Deposition  

E-Print Network [OSTI]

Laser Deposition H. Xia,a L. Lu,b,z Y. S. Meng,c and G. Cederc, * a Advanced Materials for Micro behavior of LiCoO2 thin-film cathodes prepared by pulsed laser deposition are studied for charging voltages- discharge curves. Ex situ X-ray diffraction measurements confirm structural changes and a phase transition

Ceder, Gerbrand

255

Intrinsic Surface Stability in LiMn2-xNixO4-d (x=0.45, 0.5) High Volt-age Spinel Materials for Lithium Ion Batteries  

SciTech Connect (OSTI)

This work reports the surface stability of the high voltage Li ion cathode LiMn2-xNixO4- (x= 0.5, 0.45) by comparing thin film and powder composite electrodes after cycling using X-ray photoelectron spectroscopy. The thin film electrodes offer the ability to probe the surface of the material without the need of a conductive agent and polymer binder typically used in composite electrodes. The results suggest that neither oxidation of PF6 to POF5 nor the decomposition of ethylene carbonate or dimethylene carbonate occurs on the surface of the spinel material. These results confirm the enhanced cycling stability and rate capability associated with the high voltage spinel material and suggests that the SEI layer forms due to the reaction of electrochemically inactive components in composite electrodes with the electrolyte.

Carroll, Kyler J [University of California, San Diego; Yang, Ming-Che [University of Florida, Gainesville; Veith, Gabriel M [ORNL; Dudney, Nancy J [ORNL; Meng, Ying Shirley [University of California, San Diego

2012-01-01T23:59:59.000Z

256

Analysis and design of an electronic voltage ratchet  

E-Print Network [OSTI]

and decay. Impulse voltages are produced through the discharging of 0, capacitor into a shaping network consisting of resistors and a. capacitor as is shown in Figure 2. 9. The operation of the impulse generator is as follows. Capacitor Ci is charged from... voltage shaping network. as possible in order to reduce oscillations in the wavefront and wavetail portions of the impulse voltage [1). The impulse voltage generator requires a, highly charged capacitor or bank of capacitors. Capacitors may be charged...

Menendez, Jorge Carlos

2012-06-07T23:59:59.000Z

257

Method of detecting the direction of arcing faults on power distribution feeders  

E-Print Network [OSTI]

of overcurrent relays, which Journal model is IEEE transactions on Power Delivery is required for distribution system reliability. The traveling wave directionality al- gorithms also require fairly substantial change in voltage for proper operation... is of significant magnitude to cause a current reversal in the case of a reverse fault [18]. 2. Traveling Wave Relaying The need for more accurate and fast detection of fault and direction of very high voltage transmission lines, was the base of invention...

Fernando, W. Anand Krisantha

2012-06-07T23:59:59.000Z

258

Low voltage arc formation in railguns  

DOE Patents [OSTI]

A low voltage plasma arc is first established across the rails behind the projectile by switching a low voltage high current source across the rails to establish a plasma arc by vaporizing a fuse mounted on the back of the projectile, maintaining the voltage across the rails below the railgun breakdown voltage to prevent arc formation ahead of the projectile. After the plasma arc has been formed behind the projectile a discriminator switches the full energy bank across the rails to accelerate the projectile. A gas gun injector may be utilized to inject a projectile into the breech of a railgun. The invention permits the use of a gas gun or gun powder injector and an evacuated barrel without the risk of spurious arc formation in front of the projectile.

Hawke, R.S.

1985-08-05T23:59:59.000Z

259

Low voltage arc formation in railguns  

DOE Patents [OSTI]

A low voltage plasma arc is first established across the rails behind the projectile by switching a low voltage high current source across the rails to establish a plasma arc by vaporizing a fuse mounted on the back of the projectile, maintaining the voltage across the rails below the railgun breakdown voltage to prevent arc formation ahead of the projectile. After the plasma arc has been formed behind the projectile a discriminator switches the full energy bank across the rails to accelerate the projectile. A gas gun injector may be utilized to inject a projectile into the breech of a railgun. The invention permits the use of a gas gun or gun powder injector and an evacuated barrel without the risk of spurious arc formation in front of the projectile. 2 figs.

Hawke, R.S.

1987-11-17T23:59:59.000Z

260

Low voltage arc formation in railguns  

DOE Patents [OSTI]

A low voltage plasma arc is first established across the rails behind the projectile by switching a low voltage high current source across the rails to establish a plasma arc by vaporizing a fuse mounted on the back of the projectile, maintaining the voltage across the rails below the railgun breakdown voltage to prevent arc formation ahead of the projectile. After the plasma arc has been formed behind the projectile a discriminator switches the full energy bank across the rails to accelerate the projectile. A gas gun injector may be utilized to inject a projectile into the breech of a railgun. The invention permits the use of a gas gun or gun powder injector and an evacuated barrel without the risk of spurious arc formation in front of the projectile.

Hawke, Ronald S. (Livermore, CA)

1987-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage direct" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Surface preparation for high purity alumina ceramics enabling direct brazing in hydrogen atmospheres  

DOE Patents [OSTI]

The present invention relates to a method for preparing the surface of a high purity alumina ceramic or sapphire specimen that enables direct brazing in a hydrogen atmosphere using an active braze alloy. The present invention also relates to a method for directly brazing a high purity alumina ceramic or sapphire specimen to a ceramic or metal member using this method of surface preparation, and to articles produced by this brazing method. The presence of silicon, in the form of a SiO.sub.2 -containing surface layer, can more than double the tensile bond strength in alumina ceramic joints brazed in a hydrogen atmosphere using an active Au-16Ni-0.75 Mo-1.75V filler metal. A thin silicon coating applied by PVD processing can, after air firing, produce a semi-continuous coverage of the alumina surface with a SiO.sub.2 film. Room temperature tensile strength was found to be proportional to the fraction of air fired surface covered by silicon-containing films. Similarly, the ratio of substrate fracture versus interface separation was also related to the amount of surface silicon present prior to brazing. This process can replace the need to perform a "moly-manganese" metallization step.

Cadden, Charles H. (Danville, CA); Yang, Nancy Yuan Chi (Lafayette, CA); Hosking, Floyd M. (Albuquerque, NM)

2001-01-01T23:59:59.000Z

262

THE TRENDS HIGH-CONTRAST IMAGING SURVEY. II. DIRECT DETECTION OF THE HD 8375 TERTIARY  

SciTech Connect (OSTI)

We present the direct imaging detection of a faint tertiary companion to the single-lined spectroscopic binary HD 8375 AB. Initially noticed as an 53 m s{sup -1} yr{sup -1} Doppler acceleration by Bowler et al., we have obtained high-contrast adaptive optics observations at Keck using NIRC2 that spatially resolve HD 8375 C from its host(s). Astrometric measurements demonstrate that the companion shares a common proper-motion. We detect orbital motion in a clockwise direction. Multiband relative photometry measurements are consistent with an early M-dwarf spectral type ({approx}M1V). Our combined Doppler and imaging observations place a lower-limit of m {>=} 0.297 M{sub Sun} on its dynamical mass. We also provide a refined orbit for the inner pair using recent radial velocity measurements obtained with the High Resolution Echelle Spectrometer. HD 8375 is one of many triple-star systems that are apparently missing in the solar neighborhood.

Crepp, Justin R. [Department of Physics, University of Notre Dame, 225 Nieuwland Science Hall, Notre Dame, IN 46556 (United States); Johnson, John Asher; Yantek, Scott M. [Department of Astronomy, California Institute of Technology, 1200 E. California Blvd., Pasadena, CA 91125 (United States); Howard, Andrew W. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Marcy, Geoff W.; Isaacson, Howard [Department of Astronomy, University of California, Berkeley, CA 94720 (United States); Fischer, Debra A. [Department of Physics, Yale University, New Haven, CT 06511 (United States); Wright, Jason T.; Feng Ying, E-mail: jcrepp@nd.edu [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States)

2013-07-01T23:59:59.000Z

263

Prospectively ECG-triggered high-pitch coronary angiography with third-generation dual-source CT at 70 kVp tube voltage: Feasibility, image quality, radiation dose, and effect of iterative reconstruction  

Science Journals Connector (OSTI)

AbstractBackground Low tube voltage reduces radiation exposure in coronary CT angiography (CTA). Using 70 kVp tube potential has so far not been possible because CT systems were unable to provide sufficiently high tube current with low voltage. Objective We evaluated feasibility, image quality (IQ), and radiation dose of coronary CTA using a third-generation dual-source CT system capable of producing 450 mAs tube current at 70 kVp tube voltage. Methods Coronary CTA was performed in 26 consecutive patients with suspected coronary artery disease, selected for body weight pitch spiral acquisition was used. Filtered back projection (FBP) and iterative reconstruction (IR) algorithms were applied. IQ was assessed using a 4-point rating scale (1 = excellent, 4 = nondiagnostic) and objective parameters. Results Mean age was 62 ± 9 years (46% males; mean body mass index, 27.7 ± 3.8 kg/m2; mean heart rate, 54 ± 5 beats/min). Mean dose-length product was 20.6 ± 1.9 mGy × cm; mean estimated effective radiation dose was 0.3 ± 0.03 mSv. Diagnostic IQ was found in 365 of 367 (FBP) and 366 of 367 (IR) segments (P nonsignificant). IQ was rated “excellent” in 53% (FBP) and 86% (IR) segments (P = .001) and “nondiagnostic” in 2 (FBP) and 1 segment (IR) (P nonsignificant). Mean IQ score was lesser in FBP vs IR (1.5 ± 0.4 vs 1.1 ± 0.2; P pitch spiral acquisition and 70 kVp tube voltage is feasible and provides both robust IQ and very low radiation exposure.

Michaela M. Hell; Daniel Bittner; Annika Schuhbaeck; Gerd Muschiol; Michael Brand; Michael Lell; Michael Uder; Stephan Achenbach; Mohamed Marwan

2014-01-01T23:59:59.000Z

264

Magnetic relaxation, current-voltage characteristics, and possible dissipation mechanisms for high-Tc superconducting thin films of Y-Ba-Cu-O  

Science Journals Connector (OSTI)

We propose a mechanism that may account for the temperature-insensitive relaxation of the magnetic-shielding current in epitaxial thin films of YBa2Cu3O7-?. We show that such relaxation is related to the shape of the current-voltage (J-E) characteristic of the superconductor in its critical state. The weak temperature dependence of the relaxation implies a temperature-insensitive J-E characteristic that resembles that of conventional type-II superconductors when a spatial variation of critical current density (Jc) is present. We suggest such a distribution of Jc as an explanation for the apparently large and temperature-insensitive relaxation observed in YBa2Cu3O7-?.

J. Z. Sun; C. B. Eom; B. Lairson; J. C. Bravman; T. H. Geballe

1991-02-01T23:59:59.000Z

265

Comparative Assessment of Direct Drive High Temperature Superconducting Generators in Multi-Megawatt Class Wind Turbines  

SciTech Connect (OSTI)

This paper summarizes the work completed under the CRADA between NREL and American Superconductor (AMSC). The CRADA combined NREL and AMSC resources to benchmark high temperature superconducting direct drive (HTSDD) generator technology by integrating the technologies into a conceptual wind turbine design, and comparing the design to geared drive and permanent magnet direct drive (PMDD) wind turbine configurations. Analysis was accomplished by upgrading the NREL Wind Turbine Design Cost and Scaling Model to represent geared and PMDD turbines at machine ratings up to 10 MW and then comparing cost and mass figures of AMSC's HTSDD wind turbine designs to theoretical geared and PMDD turbine designs at 3.1, 6, and 10 MW sizes. Based on the cost and performance data supplied by AMSC, HTSDD technology has good potential to compete successfully as an alternative technology to PMDD and geared technology turbines in the multi megawatt classes. In addition, data suggests the economics of HTSDD turbines improve with increasing size, although several uncertainties remain for all machines in the 6 to 10 MW class.

Maples, B.; Hand, M.; Musial, W.

2010-10-01T23:59:59.000Z

266

Direct Drive Heavy-Ion-Beam Inertial Fusion at High Coupling Efficiency  

SciTech Connect (OSTI)

Issues with coupling efficiency, beam illumination symmetry and Rayleigh Taylor (RT) instability are discussed for spherical heavy-ion-beam-driven targets with and without hohlraums. Efficient coupling of heavy ion beams to compress direct-drive inertial fusion targets without hohlraums is found to require ion range increasing several-fold during the drive pulse. One-dimensional implosion calculations using the LASNEX ICF target physics code shows the ion range increasing four-fold during the drive pulse to keep ion energy deposition following closely behind the imploding ablation front, resulting in high coupling efficiencies (shell kinetic energy/incident beam energy of 16 to 18%). Ways to increase beam ion range while mitigating Rayleigh-Taylor instabilities are discussed for future work.

Logan, B. Grant; Logan, B. Grant; Perkins, L.J.; Barnard, J.J.

2007-06-25T23:59:59.000Z

267

Controllable fabrication of high purity Mg(OH)2 nanoneedles via direct transformation of natural brucite  

Science Journals Connector (OSTI)

Abstract High purity Mg(OH)2 nanoneedles with diameters of 3–5 nm and lengths of 40–60 nm were synthesized directly from natural brucite via a facile and dissolution-free route in the presence of magnesium sulfosalicylate and polyethylene glycol (PEG, MW1000). Under hydrothermal conditions, magnesium sulfosalicylate caused layered brucite to disintegrate into thin nanosheets and could transport hydroxyl groups from the nanosheets to Mg(OH)2 crystal nuclei as a “supplier”. The PEG1000 might regulate the one-dimensional morphology and improve the purity of the Mg(OH)2 nanoneedles by forming selective hydrogen bonds on the related Mg(OH)2 crystal surfaces. Since this novel approach is simple and low-cost in comparison with wet precipitation method, the process can easily be scaled up.

Xuesong Wang; Hongchang Pang; Wendan Chen; Yuan Lin; Guiling Ning

2014-01-01T23:59:59.000Z

268

High Transverse Momentum Direct Photon Production at Fermilab Fixed-Target Energies  

SciTech Connect (OSTI)

This thesis describes a study of the production of high transverse momentum direct photons and {pi}{sup 0} mesons by proton beams at 530 and 800 GeV/c and {pi}{sup -} beams at 515 GeV/c incident on beryllium, copper, and liquid hydrogen targets. The data were collected by Fermilab experiment E706 during the 1990 and 1991-92 fixed target runs. The apparatus included a large, finely segmented lead and liquid argon electromagnetic calorimeter and a charged particle spectrometer featuring silicon strip detectors in the target region and proportional wire chambers and drift tubes downstream of a large aperture analysis magnet. The inclusive cross sections are presented as functions of transverse momentum and rapidity. The measurements are compared with next-to-leading order perturbative QCD calculations and to results from previous experiments.

Apanasevich, Leonard; /Michigan State U.

2005-05-01T23:59:59.000Z

269

Rationale for continuing R&D in direct coal conversion to produce high quality transportation fuels  

SciTech Connect (OSTI)

For the foreseeable future, liquid hydrocarbon fuels will play a significant role in the transportation sector of both the United States and the world. Factors favoring these fuels include convenience, high energy density, and the vast existing infrastructure for their production and use. At present the U.S. consumes about 26% of the world supply of petroleum, but this situation is expected to change because of declining domestic production and increasing competition for imports from countries with developing economies. A scenario and time frame are developed in which declining world resources will generate a shortfall in petroleum supply that can be allieviated in part by utilizing the abundant domestic coal resource base. One option is direct coal conversion to liquid transportation fuels. Continued R&D in coal conversion technology will results in improved technical readiness that can significantly reduce costs so that synfuels can compete economically in a time frame to address the shortfall.

Srivastava, R.D.; McIlvried, H.G. [Burns and Roe Services Corp., Pittsburgh, PA (United States); Gray, D. [Mitre Corp, McLean, VA (United States)] [and others

1995-12-31T23:59:59.000Z

270

Direct X-B mode conversion for high-? national spherical torus experiment in nonlinear regime  

SciTech Connect (OSTI)

Electron Bernstein wave (EBW) can be effective for heating and driving currents in spherical tokamak plasmas. Power can be coupled to EBW via mode conversion of the extraordinary (X) mode wave. The most common and successful approach to study the conditions for optimized mode conversion to EBW was evaluated analytically and numerically using a cold plasma model and an approximate kinetic model. The major drawback in using radio frequency waves was the lack of continuous wave sources at very high frequencies (above the electron plasma frequency), which has been addressed. A future milestone is to approach high power regime, where the nonlinear effects become significant, exceeding the limits of validity for present linear theory. Therefore, one appropriate tool would be particle in cell (PIC) simulation. The PIC method retains most of the nonlinear physics without approximations. In this work, we study the direct X-B mode conversion process stages using PIC method for incident wave frequency f{sub 0}?=?15?GHz, and maximum amplitude E{sub 0}?=?10{sup 5?}V/m in the national spherical torus experiment (NSTX). The modelling shows a considerable reduction in X-B mode conversion efficiency, C{sub modelling}?=?0.43, due to the presence of nonlinearities. Comparison of system properties to the linear state reveals predominant nonlinear effects; EBW wavelength and group velocity in comparison with linear regime exhibit an increment around ?36% and 17%, respectively.

Ali Asgarian, M., E-mail: maliasgarian@ph.iut.ac.ir, E-mail: maa@msu.edu [Physics Department, Isfahan University of Technology, Isfahan 84156 (Iran, Islamic Republic of); Department of Electrical and Computer Engineering, Michigan State University, Michigan 48824-1226 (United States); Parvazian, A.; Abbasi, M. [Physics Department, Isfahan University of Technology, Isfahan 84156 (Iran, Islamic Republic of); Verboncoeur, J. P. [Department of Electrical and Computer Engineering, Michigan State University, Michigan 48824-1226 (United States)

2014-09-15T23:59:59.000Z

271

A High Temperature Direct Vehicle Exhaust Flowmeter for Heavy Duty Diesel Emission Measurements.  

Broader source: Energy.gov [DOE]

Poster presented at the 16th Directions in Engine-Efficiency and Emissions Research (DEER) Conference in Detroit, MI, September 27-30, 2010.

272

3-Cylinder Turbocharged Gasoline Direct Injection: A High Value Solution for Euro VI Emissions  

Broader source: Energy.gov [DOE]

3-cylindery gasoline direct injection engines offer similar value in CO2 reduction capability (Euros/% CO2 reduction) at a significantly lower on-cost.

273

Planning of distribution networks for medium voltage and low voltage.  

E-Print Network [OSTI]

??Determination of the placement and rating of transformers and feeders are the main objective of the basic distribution network planning. The bus voltage and the… (more)

Ziari, Iman

2011-01-01T23:59:59.000Z

274

Triple voltage dc-to-dc converter and method  

DOE Patents [OSTI]

A circuit and method of providing three dc voltage buses and transforming power between a low voltage dc converter and a high voltage dc converter, by coupling a primary dc power circuit and a secondary dc power circuit through an isolation transformer; providing the gating signals to power semiconductor switches in the primary and secondary circuits to control power flow between the primary and secondary circuits and by controlling a phase shift between the primary voltage and the secondary voltage. The primary dc power circuit and the secondary dc power circuit each further comprising at least two tank capacitances arranged in series as a tank leg, at least two resonant switching devices arranged in series with each other and arranged in parallel with the tank leg, and at least one voltage source arranged in parallel with the tank leg and the resonant switching devices, said resonant switching devices including power semiconductor switches that are operated by gating signals. Additional embodiments having a center-tapped battery on the low voltage side and a plurality of modules on both the low voltage side and the high voltage side are also disclosed for the purpose of reducing ripple current and for reducing the size of the components.

Su, Gui-Jia (Knoxville, TN)

2008-08-05T23:59:59.000Z

275

REFINED RFP LOOP VOLTAGE CALCULATION J.C. Sprott  

E-Print Network [OSTI]

is the stored magnetic energy, Up is the plasma energy, and 'E is the global energy confinement time, which-of-merit for RFP devices is the loop voltage. Low loop voltage implies high plasma temperature and long energy is smallest if the loop is as close to the outside of the shell and as far from the primary windings

Sprott, Julien Clinton

276

Direct high-precision measurement of the magnetic moment of the proton  

E-Print Network [OSTI]

The spin-magnetic moment of the proton $\\mu_p$ is a fundamental property of this particle. So far $\\mu_p$ has only been measured indirectly, analysing the spectrum of an atomic hydrogen maser in a magnetic field. Here, we report the direct high-precision measurement of the magnetic moment of a single proton using the double Penning-trap technique. We drive proton-spin quantum jumps by a magnetic radio-frequency field in a Penning trap with a homogeneous magnetic field. The induced spin-transitions are detected in a second trap with a strong superimposed magnetic inhomogeneity. This enables the measurement of the spin-flip probability as a function of the drive frequency. In each measurement the proton's cyclotron frequency is used to determine the magnetic field of the trap. From the normalized resonance curve, we extract the particle's magnetic moment in units of the nuclear magneton $\\mu_p=2.792847350(9)\\mu_N$. This measurement outperforms previous Penning trap measurements in terms of precision by a factor of about 760. It improves the precision of the forty year old indirect measurement, in which significant theoretical bound state corrections were required to obtain $\\mu_p$, by a factor of 3. By application of this method to the antiproton magnetic moment $\\mu_{\\bar{p}}$ the fractional precision of the recently reported value can be improved by a factor of at least 1000. Combined with the present result, this will provide a stringent test of matter/antimatter symmetry with baryons.

A. Mooser; S. Ulmer; K. Blaum; K. Franke; H. Kracke; C. Leiteritz; W. Quint; C. C. Rodegheri; C. Smorra; J. Walz

2014-06-18T23:59:59.000Z

277

Direct hybridization of tin oxide/graphene nanocomposites for highly efficient lithium-ion battery anodes  

Science Journals Connector (OSTI)

A facile direct hybridization route to prepare SnO2/graphene nanocomposites for Li-ion battery anode application is demonstrated. Uniform distribution of...2 nanoparticles on graphene layers was enabled by a one-...

Dong Ok Shin; Hun Park; Young-Gi Lee; Kwang Man Kim…

2014-06-01T23:59:59.000Z

278

A high-order accurate accelerated direct solver for acoustic scattering from surfaces  

Science Journals Connector (OSTI)

We describe an accelerated direct solver for the integral equations which model low-frequency acoustic scattering from curved surfaces. Surfaces are specified via a collection of smooth parameterizations given...

James Bremer; Adrianna Gillman; Per-Gunnar Martinsson

2014-07-01T23:59:59.000Z

279

Design of high-ionic conductivity electrodes for direct methanol fuel cells  

E-Print Network [OSTI]

Carbon-supported porous electrodes are used in low-temperature fuel cells to provide maximum catalyst surface area, while taking up little volume and using minimum catalyst material. In Direct Methanol Fuel Cells (DMFCs), ...

Schrauth, Anthony J

2011-01-01T23:59:59.000Z

280

Definition: Direct current | Open Energy Information  

Open Energy Info (EERE)

Definition Definition Edit with form History Facebook icon Twitter icon » Definition: Direct current Jump to: navigation, search Dictionary.png Direct current A type of electricity transmission and distribution by which electricity flows in one direction through the conductor, usually relatively low voltage and high current (such as from a battery). To be used for typical 120 volt or 220 volt household appliances, DC must be converted to alternating current (AC).[1][2] View on Wikipedia Wikipedia Definition Direct current (DC) is the unidirectional flow of electric charge. Direct current is produced by sources such as batteries, thermocouples, solar cells, and commutator-type electric machines of the dynamo type. Direct current may flow in a conductor such as a wire, but can also flow

Note: This page contains sample records for the topic "high voltage direct" from the National Library of EnergyBeta (NLEBeta).
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281

Intrinsic Surface Stability in LiMn2-xNix04-s (x = 0.45, 0.5) High Voltage Spinel Materials for Lithium Ion Batteries  

SciTech Connect (OSTI)

This work reports the surface stability of the high vollage Li ion cathode LiMn2_,Ni,Ooh\\ (x = 0.5, 0.45) by comparing thin fi lm and powder composite electrodes after cycling using X-ray photoelectron spectroscopy. The thin film electrodes offer the abili ty to probe the surface of the material without the need of a conductive agent and polymer binder typically used in composite electrodes. The resulls suggest that neither oxidation of PP6 to POF3 nor the decomposition of ethylene carbonate or dimethylene carbonate occurs on the surface of the spinel material. These resulls confirm the enhanced cycling stability and rate capability associated with the high vollage spinel material and suggests that the SE!IIayer fonns due to the reaction of electrochemically inactive components in composite electrodes with the electrolyte.

Carroll, Kyler J [University of California, San Diego; Yang, Ming-Che [University of Florida, Gainesville; Veith, Gabriel M [ORNL; Dudney, Nancy J [ORNL; Meng, Ying Shirley [University of California, San Diego

2012-01-01T23:59:59.000Z

282

LM139/LM239/LM339/LM2901/LM3302 Low Power Low Offset Voltage Quad Comparators  

E-Print Network [OSTI]

LM139/LM239/LM339/LM2901/LM3302 Low Power Low Offset Voltage Quad Comparators General Description The LM139 series consists of four independent precision voltage comparators with an offset voltage clock timers; multivibrators and high voltage digital logic gates. The LM139 series was designed

Lanterman, Aaron

283

A NEW HIGH FREQUENCY GLOBAL-TO-DIRECT IRRADIANCE CONVERSION METHODOLOGY  

E-Print Network [OSTI]

, Navarra (Spain) Abstract In order to accurately simulate the behavior of a solar thermal power plant will improve results of solar thermal power plants simulations. Keywords: Direct Normal Irradiance (DNI by knowing this information with accuracy, it will be possible to predict the solar thermal power plant

Paris-Sud XI, Université de

284

Optimization of direct drive induction motors for electric ship propulsion with high speed propellers  

Science Journals Connector (OSTI)

Direct drive electric ship propulsion can offer increased flexibility and reduced overall fuel consumption compared to geared mechanical systems [Davis 1987, Doerry 2007]. As a well-established technology, induction motors are a dependable and economical ... Keywords: AC motors, induction motor drives, induction motors, thermal analysis

S. C. Englebretson; J. L. Kirtley, Jr; C. Chryssostomidis

2009-07-01T23:59:59.000Z

285

Low voltage nonprimary explosive detonator  

DOE Patents [OSTI]

A low voltage, electrically actuated, nonprimary explosive detonator is disclosed wherein said detonation is achieved by means of an explosive train in which a deflagration-to-detonation transition is made to occur. The explosive train is confined within a cylindrical body and positioned adjacent to low voltage ignition means have electrical leads extending outwardly from the cylindrical confining body. Application of a low voltage current to the electrical leads ignites a self-sustained deflagration in a donor portion of the explosive train which then is made to undergo a transition to detonation further down the train.

Dinegar, Robert H. (Los Alamos, NM); Kirkham, John (Newbury, GB2)

1982-01-01T23:59:59.000Z

286

Langmuir probe measurements in a time-fluctuating-highly ionized non-equilibrium cutting arc: Analysis of the electron retarding part of the time-averaged current-voltage characteristic of the probe  

SciTech Connect (OSTI)

This work describes the application of Langmuir probe diagnostics to the measurement of the electron temperature in a time-fluctuating-highly ionized, non-equilibrium cutting arc. The electron retarding part of the time-averaged current-voltage characteristic of the probe was analysed, assuming that the standard exponential expression describing the electron current to the probe in collision-free plasmas can be applied under the investigated conditions. A procedure is described which allows the determination of the errors introduced in time-averaged probe data due to small-amplitude plasma fluctuations. It was found that the experimental points can be gathered into two well defined groups allowing defining two quite different averaged electron temperature values. In the low-current region the averaged characteristic was not significantly disturbed by the fluctuations and can reliably be used to obtain the actual value of the averaged electron temperature. In particular, an averaged electron temperature of 0.98 ± 0.07 eV (= 11400 ± 800 K) was found for the central core of the arc (30 A) at 3.5 mm downstream from the nozzle exit. This average included not only a time-average over the time fluctuations but also a spatial-average along the probe collecting length. The fitting of the high-current region of the characteristic using such electron temperature value together with the corrections given by the fluctuation analysis showed a relevant departure of local thermal equilibrium in the arc core.

Prevosto, L.; Mancinelli, B. [Grupo de Descargas Eléctricas, Departamento Ing. Electromecánica, Facultad Regional Venado Tuerto (UTN), Laprida 651, Venado Tuerto (2600) Santa Fe (Argentina)] [Grupo de Descargas Eléctricas, Departamento Ing. Electromecánica, Facultad Regional Venado Tuerto (UTN), Laprida 651, Venado Tuerto (2600) Santa Fe (Argentina); Kelly, H. [Grupo de Descargas Eléctricas, Departamento Ing. Electromecánica, Facultad Regional Venado Tuerto (UTN), Laprida 651, Venado Tuerto (2600) Santa Fe (Argentina) [Grupo de Descargas Eléctricas, Departamento Ing. Electromecánica, Facultad Regional Venado Tuerto (UTN), Laprida 651, Venado Tuerto (2600) Santa Fe (Argentina); Instituto de Física del Plasma (CONICET), Departamento de Física, Facultad de Ciencias Exactas y Naturales (UBA) Ciudad Universitaria Pab. I, 1428 Buenos Aires (Argentina)

2013-12-15T23:59:59.000Z

287

Nickel-hydrogen voltage-efficiency model  

SciTech Connect (OSTI)

A model for providing voltage vs. current relationships and coulombic efficiency has been developed applicable to Nickel-Hydrogen (NiH{sub 2}) batteries. The performance relationships can be used directly in dynamic electrical energy storage system models or customized by predicting the particular case of voltage as a function of applied current. The algorithm utilizes electrochemical models for competing cell reactions: a single Butler-Volmer equation for the main NiH{sub 2} reaction, and a Tafel relationship for oxygen generation. For the main NiH{sub 2} reaction, the dependence on state-of-charge is introduced via a Nerstian term containing concentrations of active materials present. Oxygen recombination and self-discharge are modeled as first order reactions. Model parameters are determined by a modified Marquardt algorithm to provide a best-fit of both voltage and pressure data to the physical model. The data fit is from electrical characterization tests which may include capacity measurements or repeated electrical cycling at specified depths-of-discharge or with particular regimens. It has been found that test performance data covering a wide domain of the independent variables (temperature, current, and state-of-charge) will produce a well-behaved model.

Hafen, D.P.; Armantrout, J.D. [Lockheed Martin Missiles and Space, Sunnyvale, CA (United States)

1996-12-31T23:59:59.000Z

288

DSP IMPLEMENTATION OF DC VOLTAGE REGULATION USING ADAPTIVE CONTROL FOR 200 KW 62000 RPM  

E-Print Network [OSTI]

to control the DC voltage for 200 kW induction generator rated at a speed of 62000 RPM under different load to regulate the DC voltage for high speed induction generators rated from 5 kW to 200 kW. ii #12DSP IMPLEMENTATION OF DC VOLTAGE REGULATION USING ADAPTIVE CONTROL FOR 200 KW 62000 RPM INDUCTION

Wu, Thomas

289

Definition: Automated Voltage Regulators | Open Energy Information  

Open Energy Info (EERE)

Regulators Regulators Jump to: navigation, search Dictionary.png Automated Voltage Regulators Voltage regulators are transformers that can increase or decrease the voltage on a distribution circuit to help keep the voltage within a pre-determined band. Unlike capacitor banks, voltage regulators cannot adjust power factor. These devices typically monitor the voltage at the location where they are connected, and compare it to a programmed set point. If the voltage deviates too far from the set point, the voltage regulator can increase or decrease its output voltage by moving the tap on the secondary side up or down. An automated voltage regulator can operate with remote control signals, or in concert with other area voltage control devices, to help regulate distribution voltage in a coordinated fashion.

290

Open-cycle magnetohydrodynamic power plant based upon direct-contact closed-loop high-temperature heat exchanger  

DOE Patents [OSTI]

A magnetohydrodynamic (MHD) power generating system in which ionized combustion gases with slag and seed are discharged from an MHD combustor and pressurized high temperature inlet air is introduced into the combustor for supporting fuel combustion at high temperatures necessary to ionize the combustion gases, and including a heat exchanger in the form of a continuous loop with a circulating heat transfer liquid such as copper oxide. The heat exchanger has an upper horizontal channel for providing direct contact between the heat transfer liquid and the combustion gases to cool the gases and condense the slag which thereupon floats on the heat transfer liquid and can be removed from the channel, and a lower horizontal channel for providing direct contact between the heat transfer liquid and pressurized air for preheating the inlet air. The system further includes a seed separator downstream of the heat exchanger.

Berry, Gregory F. (Naperville, IL); Minkov, Vladimir (Skokie, IL); Petrick, Michael (Joliet, IL)

1988-01-01T23:59:59.000Z

291

Saving Megawatts with Voltage Optimization  

E-Print Network [OSTI]

that had been installed at several electric utility distribution substations in the U.S. and Canada. These systems, being operated in Conservation Voltage Regulation mode, have provided significant energy conservation where they have been installed...

Wilson, T.; Bell, D.

2010-01-01T23:59:59.000Z

292

A balloon borne detector to determine high energy neutrons in energy and direction  

Science Journals Connector (OSTI)

A balloon borne experiment for the measurement of solar and atmospheric neutrons in energy and direction above 50 MeV is described. The principle of measurement is the double elastic scattering process of the incoming neutrons with hydrogen atoms. For the registration of the recoil protons spark chambers are used. The hydrogen is contained in thin plastic scintillator and polyethylene plates, which are inserted between the spark chambers. The sparks are recorded photographically from two sides. A detailed description of the design of the experiment is given. The properties of the apparatus were determined by atmospheric neutron measurements at ground level.

E. Heidbreder; K. Pinkau; C. Reppin; V. Schönfelder

1970-01-01T23:59:59.000Z

293

Direct photonic production: towards high speed additive manufacturing of individualized goods  

Science Journals Connector (OSTI)

Especially the scale-scope dilemma is boosted by global trends like mass customization and open innovation which result in a highly fluctuating demand for individualized products at costs matching or beating thos...

H. Schleifenbaum; A. Diatlov; C. Hinke; J. Bültmann…

2011-08-01T23:59:59.000Z

294

Dry coating of micronized API powders for improved dissolution of directly compacted tablets with high drug loading  

Science Journals Connector (OSTI)

Motivated by our recent study showing improved flow and dissolution rate of the active pharmaceutical ingredient (API) powders (20 ?m) produced via simultaneous micronization and surface modification through continuous fluid energy milling (FEM) process, the performance of blends and direct compacted tablets with high drug loading is examined. Performance of 50 ?m API powders dry coated without micronization is also considered for comparison. Blends of micronized, non-micronized, dry coated or uncoated API powders at 30, 60 and 70% drug loading, are examined. The results show that the blends containing dry coated API powders, even micronized ones, have excellent flowability and high bulk density compared to the blends containing uncoated API, which are required for direct compaction. As the drug loading increases, the difference between dry coated and uncoated blends is more pronounced, as seen in the proposed bulk density-FFC phase map. Dry coating led to improved tablet compactibility profiles, corresponding with the improvements in blend compressibility. The most significant advantage is in tablet dissolution where for all drug loadings, the t80 for the tablets with dry coated \\{APIs\\} was well under 5 min, indicating that this approach can produce nearly instant release direct compacted tablets at high drug loadings.

Xi Han; Chinmay Ghoroi; Rajesh Davé

2013-01-01T23:59:59.000Z

295

High efficiency direct fuel cell hybrid power cycle for near term application  

SciTech Connect (OSTI)

Direct carbonate fuel cells being developed by Energy Research Corporation can generate power at an efficiency approaching 60% LHV. This unique fuel cell technology can consume natural gas and other hydrocarbon based fuels directly without requiring an external reformer, thus providing a simpler and inherently efficient power generation system. A 2 MW power plant demonstration of this technology has been initiated at an installation in the city of Santa Clara in California. A 2.85 MW commercial configuration shown in Figure 1 is presently being developed. The complete plant includes the carbonate fuel cell modules, an inverter, transformer and switchgear, a heat recovery unit and supporting instrument air and water treatment systems. The emission levels for this 2.85 MW plant are projected to be orders of magnitude below existing or proposed standards. The 30 year levelized cost of electricity, without inflation, is projected to be approximately 5{cents}/kW-h assuming capital cost for the carbonate fuel cell system of $1000/kW.

Steinfeld, G.; Maru, H.C. [Energy Research Corp., Danbury, CT (United States); Sanderson, R.A. [Fuel Cell Systems Consultant, Wethersfield, CT (United States)

1996-12-31T23:59:59.000Z

296

An experimental investigation of high performance natural gas engine with direct injection  

Science Journals Connector (OSTI)

This paper presents experimental results of a new compressed natural gas direct injection (CNG-DI) engine that has been developed from modification of a multi cylinder gasoline port injection (PI) engine. The original gasoline-PI engine was also modified to a CNG bi-fuel system. The test results obtained from CNG fuel using two different systems (i.e. bi-fuel and DI) have been investigated and compared with the original gasoline engine. The objective of this investigation is to compare the test results between CNG-DI, with CNG-BI and gasoline-PI engines with the same displacement volume. It was found that the CNG-DI engine produces similar brake power at 6000 rpm and wide open throttle (WOT) but produces higher brake power at part load condition as compared to the original gasoline. The CNG-BI engine produces 23% lower brake power than the CNG-DI engine. The average brake specific fuel consumption (BSFC) of the CNG-DI engine was 0.28% and 8% lower than gasoline-PI and CNG-BI engines respectively. The CNG-DI engine reduces 42% \\{NOx\\} emission as compared to the base engine. However, the CNG-DI engine produces higher HC and CO emissions as compared to the base engine. This paper discusses a review on the direct injection (DI) natural gas engine with new information along with other investigations.

M.A. Kalam; H.H. Masjuki

2011-01-01T23:59:59.000Z

297

A Low-cost, High-yield Process for the Direct Productin of High Energy Density Liquid Fuel from Biomass  

SciTech Connect (OSTI)

The primary objective and outcome of this project was the development and validation of a novel, low-cost, high-pressure fast-hydropyrolysis/hydrodeoxygenation (HDO) process (H{sub 2}Bioil) using supplementary hydrogen (H{sub 2}) to produce liquid hydrocarbons from biomass. The research efforts under the various tasks of the project have culminated in the first experimental demonstration of the H2Bioil process, producing 100% deoxygenated >C4+ hydrocarbons containing 36-40% of the carbon in the feed of pyrolysis products from biomass. The demonstrated H{sub 2}Bioil process technology (i.e. reactor, catalyst, and downstream product recovery) is scalable to a commercial level and is estimated to be economically competitive for the cases when supplementary H{sub 2} is sourced from coal, natural gas, or nuclear. Additionally, energy systems modeling has revealed several process integration options based on the H{sub 2}Bioil process for energy and carbon efficient liquid fuel production. All project tasks and milestones were completed or exceeded. Novel, commercially-scalable, high-pressure reactors for both fast-hydropyrolysis and hydrodeoxygenation were constructed, completing Task A. These reactors were capable of operation under a wide-range of conditions; enabling process studies that lead to identification of optimum process conditions. Model compounds representing biomass pyrolysis products were studied, completing Task B. These studies were critical in identifying and developing HDO catalysts to target specific oxygen functional groups. These process and model compound catalyst studies enabled identification of catalysts that achieved 100% deoxygenation of the real biomass feedstock, sorghum, to form hydrocarbons in high yields as part of Task C. The work completed during this grant has identified and validated the novel and commercially scalable H2Bioil process for production of hydrocarbon fuels from biomass. Studies on model compounds as well as real biomass feedstocks were utilized to identify optimized process conditions and selective HDO catalyst for high yield production of hydrocarbons from biomass. In addition to these experimental efforts, in Tasks D and E, we have developed a mathematical optimization framework to identify carbon and energy efficient biomass-to-liquid fuel process designs that integrate the use of different primary energy sources along with biomass (e.g. solar, coal or natural gas) for liquid fuel production. Using this tool, we have identified augmented biomass-to-liquid fuel configurations based on the fast-hydropyrolysis/HDO pathway, which was experimentally studied in this project. The computational approach used for screening alternative process configurations represents a unique contribution to the field of biomass processing for liquid fuel production.

Agrawal, Rakesh

2014-02-21T23:59:59.000Z

298

Superconducting Fault Current Limiter for Transmission Voltage  

Science Journals Connector (OSTI)

Within a collaboration of American Superconductor, Siemens, Nexans and Southern California Edison one electrical phase of a resistive superconducting fault current limiter for the 115 kV transmission voltage level has been designed and manufactured. The active part of the limiter consists of 63 bifilar coils made of 12 mm wide steel-stabilized YBCO conductor and is housed in a cryostat operated at 5 bar and 74 K. The first phase was completely assembled and successfully subjected to power switching tests and high voltage tests. The basic design of the system and the test results are reported. The work was funded in part by US-DOE under Contract Number DE-FC26-07NT43243.

Hans-Peter Kraemer; Wolfgang Schmidt; Hong Cai; Bruce Gamble; David Madura; Tim MacDonald; Joe McNamara; Walther Romanosky; Greg Snitchler; Nicolas Lallouet; Frank Schmidt; Syed Ahmed

2012-01-01T23:59:59.000Z

299

Methyl Chloride from Direct Methane Partial Oxidation: A High-Temperature Shilov-Like Catalytic System  

SciTech Connect (OSTI)

The intention of this study is to demonstrate and evaluate the scientific and economic feasibility of using special solvents to improve the thermal stability of Pt-catalyst in the Shilov system, such that a high reaction temperature could be achieved. The higher conversion rate (near 100%) of methyl chloride from partial oxidation of methane under the high temperature ({approx} 200 C) without significant Pt0 precipitation has been achieved. High concentration of the Cl- ion has been identified as the key for the stabilization of the Pt-catalysts. H/D exchange measurements indicated that the over oxidation will occur at the elevated temperature, developments of the effective product separation processes will be necessary in order to rationalize the industry-visible CH4 to CH3Cl conversion.

Yongchun Tang; John (Qisheng) Ma

2012-03-23T23:59:59.000Z

300

Direct high-resolution characterization of quantum correlations via classical measurements  

E-Print Network [OSTI]

Quantum optics plays a central role in the study of fundamental concepts in quantum mechanics, and in the development of new technological applications. Typical experiments employ non-classical light, such as entangled photons, generated by parametric processes. The standard characterization of the sources by quantum tomography, which relies on detecting the pairs themselves and thus requires single photon detectors, limits both measurement speed and accuracy. Here we show that the spectral characterization of the quantum correlations generated by two-photon sources can be directly performed classically with an unprecedented spectral resolution. This streamlined technique has the potential to speed up design and testing of massively parallel integrated sources by providing a fast and reliable quality control procedure. Adapting our method to explore other degrees of freedom would allow the complete characterization of biphoton states generated by parametric processes.

Andreas Eckstein; Guillaume Boucher; Aristide Lemaître; Pascal Filloux; Ivan Favero; Giuseppe Leo; John E. Sipe; Marco Liscidini; Sara Ducci

2013-12-15T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage direct" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Optically initiated silicon carbide high voltage switch  

DOE Patents [OSTI]

An improved photoconductive switch having a SiC or other wide band gap substrate material, such as GaAs and field-grading liners composed of preferably SiN formed on the substrate adjacent the electrode perimeters or adjacent the substrate perimeters for grading the electric fields.

Caporaso, George J. (Livermore, CA); Sampayan, Stephen E. (Manteca, CA); Sullivan, James S. (Livermore, CA); Sanders; David M. (Livermore, CA)

2011-02-22T23:59:59.000Z

302

HIGH-VOLTAGE SPINEL AND POLYANION CATHODES  

Broader source: Energy.gov (indexed) [DOE]

POLYANION CATHODES ARUMUGAM MANTHIRAM Electrochemical Energy Laboratory (ECEL) Materials Science and Engineering Program The University of Texas at Austin May 14, 2012 Project ID...

303

Lockout device for high voltage circuit breaker  

SciTech Connect (OSTI)

An improved lockout assembly is provided for a circuit breaker to lock the switch handle into a selected switch position. The lockout assembly includes two main elements, each having a respective foot for engaging a portion of the upper housing wall of the circuit breaker. The first foot is inserted into a groove in the upper housing wall, and the second foot is inserted into an adjacent aperture (e.g., a slot) in the upper housing wall. The first foot is slid under and into engagement with a first portion, and the second foot is slid under and into engagement with a second portion of the upper housing wall. At the same time the respective two feet are placed in engagement with the respective portions of the upper housing wall, two holes, one on each of the respective two main elements of the assembly, are placed in registration; and a locking device, such as a special scissors equipped with a padlock, is installed through the registered holes to secure the lockout assembly on the circuit breaker. When the lockout assembly of the invention is secured on the circuit breaker, the switch handle of the circuit breaker is locked into the selected switch position and prevented from being switched to another switch position.

Kozlowski, L.J.; Shirey, L.A.

1993-01-26T23:59:59.000Z

304

Lockout device for high voltage circuit breaker  

DOE Patents [OSTI]

An improved lockout assembly is provided for a circuit breaker to lock the switch handle into a selected switch position. The lockout assembly includes two main elements, each having a respective foot for engaging a portion of the upper housing wall of the circuit breaker. The first foot is inserted into a groove in the upper housing wall, and the second foot is inserted into an adjacent aperture (e.g., a slot) in the upper housing wall. The first foot is slid under and into engagement with a first portion, and the second foot is slid under and into engagement with a second portion of the upper housing wall. At the same time the repsective two feet are placed in engagement with the respective portions of the upper housing wall, two holes, one on each of the respective two main elements of the assembly, are placed in registration; and a locking device, such as a special scissors equipped with a padlock, is installed through the registered holes to secure the lockout assembly on the circuit breaker. When the lockout assembly of the invention is secured on the circuit breaker, the switch handle of the circuit breaker is locked into the selected switch position and prevented from being switched to another switch position.

Kozlowski, Lawrence J. (New Kensington, PA); Shirey, Lawrence A. (North Huntingdon, PA)

1993-01-01T23:59:59.000Z

305

Lookout device for high voltage circuit breaker  

SciTech Connect (OSTI)

An improved lockout assembly is provided for a circuit breaker to lock the switch handle into a selected switch position. The lockout assembly includes two main elements, each having a respective foot for engaging a portion of the upper housing wall of the circuit breaker. The first foot is inserted into a groove in the upper housing wall, and the second foot is inserted into an adjacent aperture (e.g., a slot) in the upper housing wall. The first foot is slid under and into engagement with a first portion, and the second foot is slid under and into engagement with a second portion of the upper housing wall. At the same time the respective two feet are placed in engagement with the respective portions of the upper housing wall, two holes, one on each of the respective two main elements of the assembly, are placed in registration; and a locking device, such as a special scissors equipped with a padlock, is installed through the registered holes to secure the lockout assembly on the circuit breaker. When the lockout assembly of the invention is secured on the circuit breaker, the switch handle of the circuit breaker is locked into the selected switch position and prevented from being switched to another switch position.

Kozlowski, L.J.; Shirey, L.A.

1991-12-31T23:59:59.000Z

306

High Voltage Power Supply Capacitor Problem Analysis  

E-Print Network [OSTI]

evidence of pits on the surface. One pit showed evidence that the silver had burned thru. It was concluded this was the shorted area.. A microsection of the capacitor (see photomicrograph #1} shows a pit in the dielectric material. Photomicrograph #2 shows another pit in the same capacitor. 2. 3 A total of eighteen capacitors

Rathbun, Julie A.

307

Production of high voltage by ion bombardment  

E-Print Network [OSTI]

E-08 2000 0. 511 1999. 489 5. 120E-08 0. 539 1999. 461 5. 401E-08 2500 O. B39 2499. 361 6. 403E-DB 0. 675 2499. 325 6. 764E-DB 3000 0. 769 2999. 231 7. 705E-OB 0. 810 2999. 190 8. 116E-OB 3500 0. 899 3499. 101 9. 008E-OB 0. 948 3499. 054 9. 479E...E-08 2000 0. 511 1999. 489 5. 120E-08 0. 539 1999. 461 5. 401E-08 2500 O. B39 2499. 361 6. 403E-DB 0. 675 2499. 325 6. 764E-DB 3000 0. 769 2999. 231 7. 705E-OB 0. 810 2999. 190 8. 116E-OB 3500 0. 899 3499. 101 9. 008E-OB 0. 948 3499. 054 9. 479E...

Phinney, Lucas Carter

2012-06-07T23:59:59.000Z

308

HIGH-VOLTAGE SPINEL AND POLYANION CATHODES  

Broader source: Energy.gov [DOE]

2012 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting

309

High Voltage Electrolyte for Lithium Batteries  

Broader source: Energy.gov [DOE]

2012 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting

310

High voltage photo switch package module  

DOE Patents [OSTI]

A photo-conductive switch package module having a photo-conductive substrate or wafer with opposing electrode-interface surfaces, and at least one light-input surface. First metallic layers are formed on the electrode-interface surfaces, and one or more optical waveguides having input and output ends are bonded to the substrate so that the output end of each waveguide is bonded to a corresponding one of the light-input surfaces of the photo-conductive substrate. This forms a waveguide-substrate interface for coupling light into the photo-conductive wafer. A dielectric material such as epoxy is then used to encapsulate the photo-conductive substrate and optical waveguide so that only the metallic layers and the input end of the optical waveguide are exposed. Second metallic layers are then formed on the first metallic layers so that the waveguide-substrate interface is positioned under the second metallic layers.

Sullivan, James S; Sanders, David M; Hawkins, Steven A; Sampayan, Stephen E

2014-02-18T23:59:59.000Z

311

High-voltage-compatible, fully depleted CCDs  

E-Print Network [OSTI]

B. Flaugher, “The dark energy survey,” Inter. J. of ModernTelescope (LSST), 1 the Dark Energy Survey camera, 2 the

2006-01-01T23:59:59.000Z

312

A Possible Mechanism of Direct Production of Muon Pairs at High Energies  

Science Journals Connector (OSTI)

......significant fraction of cosmic ray muons with energies greater than several TeVis produced...separation much greater than twice the muon rest energy, the probability of muon pair...meson produc- tion by very high energy muons.7) It should be noted that......

Satio Hayakawa; Ken Kikuchi

1969-02-01T23:59:59.000Z

313

Directed evolution of an ultrastable carbonic anhydrase for highly efficient carbon capture from flue gas  

Science Journals Connector (OSTI)

...library generation, and high-throughput...year, coal-fired power plants are...natural-gas–fired power...1. Flue gas from a coal-fired power plant is piped...depleted flue gas is released into...strategy for the generation of very large...

Oscar Alvizo; Luan J. Nguyen; Christopher K. Savile; Jamie A. Bresson; Satish L. Lakhapatri; Earl O. P. Solis; Richard J. Fox; James M. Broering; Michael R. Benoit; Sabrina A. Zimmerman; Scott J. Novick; Jack Liang; James J. Lalonde

2014-01-01T23:59:59.000Z

314

A direct AC-to-DC converter topology with high-frequency isolation  

E-Print Network [OSTI]

-to-ac converter eliminating the acto-dc rectification stage, power factor correction boost stage, and dc-dc converter stage present in the conventional system. The output of the high-frequency isolation transformer is rectified and processed via a filtering stage...

Sulistyono, Widodo

2012-06-07T23:59:59.000Z

315

Airflow Characteristics of Direct-Type Kitchen Hood Systems in High-Rise Apartment Buildings  

E-Print Network [OSTI]

, Samsung C&T, South Korea 2 Introduction ? Today?s high-rise apartment buildings exhibit high degree of air-tightness. ? They are also subjected to stack effect and seasonal, unpredictable, wind pressure variations. ? Therefore, it is questionable... characteristics for alt0 16 32CMH 0Pa 42CMH 0Pa 74CMH 16Pa 477CMH 984CMH 355CMH 815CMH 173CMH 26Pa 0CMH 0CMH 0CMH 54CMH 0Pa 158CMH 1Pa 35CMH 0Pa 74CMH 18Pa (a)?On?3rd?floor?at?12:00,?Jan?1st 1.5m/s North 50CMH 1Pa 23CMH 0Pa 75CMH 18Pa...

Park, M.

2011-01-01T23:59:59.000Z

316

Electro-optic voltage sensor with Multiple Beam Splitting  

DOE Patents [OSTI]

A miniature electro-optic voltage sensor system capable of accurate operation at high voltages without use of the dedicated voltage dividing hardware. The invention achieves voltage measurement without significant error contributions from neighboring conductors or environmental perturbations. The invention employs a transmitter, a sensor, a detector, and a signal processor. The transmitter produces a beam of electromagnetic radiation which is routed into the sensor. Within the sensor the beam undergoes the Pockels electro-optic effect. The electro-optic effect produces a modulation of the beam's polarization, which is in turn converted to a pair of independent conversely-amplitude-modulated signals, from which the voltage of the E-field is determined by the signal processor. The use of converse AM signals enables the signal processor to better distinguish signal from noise. The sensor converts the beam by splitting the beam in accordance with the axes of the beam's polarization state (an ellipse) into at least two AM signals. These AM signals are fed into a signal processor and processed to determine the voltage between a ground conductor and the conductor on which voltage is being measured.

Woods, Gregory K. (Cornelius, OR); Renak, Todd W. (Idaho Falls, ID); Crawford, Thomas M. (Idaho Falls, ID); Davidson, James R. (Idaho Falls, ID)

2000-01-01T23:59:59.000Z

317

Electro-optic voltage sensor with beam splitting  

DOE Patents [OSTI]

The invention is a miniature electro-optic voltage sensor system capable of accurate operation at high voltages without use of the dedicated voltage dividing hardware typically found in the prior art. The invention achieves voltage measurement without significant error contributions from neighboring conductors or environmental perturbations. The invention employs a transmitter, a sensor, a detector, and a signal processor. The transmitter produces a beam of electromagnetic radiation which is routed into the sensor. Within the sensor the beam undergoes the Pockels electro-optic effect. The electro-optic effect produces a modulation of the beam's polarization, which is in turn converted to a pair of independent conversely-amplitude-modulated signals, from which the voltage of the E-field is determined by the signal processor. The use of converse AM signals enables the signal processor to better distinguish signal from noise. The sensor converts the beam by splitting the beam in accordance with the axes of the beam's polarization state (an ellipse) into at least two AM signals. These AM signals are fed into a signal processor and processed to determine the voltage between a ground conductor and the conductor on which voltage is being measured.

Woods, Gregory K. (Cornelius, OR); Renak, Todd W. (Idaho Falls, ID); Davidson, James R. (Idaho Falls, ID); Crawford, Thomas M. (Idaho Falls, ID)

2002-01-01T23:59:59.000Z

318

Voltage, energy and power in electric circuits  

E-Print Network [OSTI]

Voltage, energy and power in electric circuits Science teaching unit #12;Disclaimer The Department-2008DVD-EN Voltage, energy and power in electric circuits #12;#12;© Crown copyright 2008 1The National Strategies | Secondary Voltage, energy and power in electric circuits 00094-2008DVD-EN Contents Voltage

Berzins, M.

319

Electro-optic voltage sensor head  

DOE Patents [OSTI]

The invention is an electro-optic voltage sensor head designed for integration with existing types of high voltage transmission and distribution apparatus. The sensor head contains a transducer, which comprises a transducing material in which the Pockels electro-optic effect is observed. In the practice of the invention at least one beam of electromagnetic radiation is routed into the transducing material of the transducer in the sensor head. The beam undergoes an electro-optic effect in the sensor head when the transducing material is subjected to an E-field. The electro-optic effect is observed as a differential phase a shift, also called differential phase modulation, of the beam components in orthogonal planes of the electromagnetic radiation. In the preferred embodiment the beam is routed through the transducer along an initial axis and then reflected by a retro-reflector back substantially parallel to the initial axis, making a double pass through the transducer for increased measurement sensitivity. The preferred embodiment of the sensor head also includes a polarization state rotator and at least one beam splitter for orienting the beam along major and minor axes and for splitting the beam components into two signals which are independent converse amplitude-modulated signals carrying E-field magnitude and hence voltage information from the sensor head by way of optic fibers.

Crawford, Thomas M. (Idaho Falls, ID); Davidson, James R. (Idaho Falls, ID); Woods, Gregory K. (Cornelius, OR)

1999-01-01T23:59:59.000Z

320

Direct ion flux measurements at high-pressure-depletion conditions for microcrystalline silicon deposition  

SciTech Connect (OSTI)

The contribution of ions to the growth of microcrystalline silicon thin films has been investigated in the well-known high-pressure-depletion (HPD) regime by coupling thin-film analysis with plasma studies. The ion flux, measured by means of a capacitive probe, has been studied in two regimes, i.e., the amorphous-to-microcrystalline transition regime and a low-to-high power regime; the latter regime had been investigated to evaluate the impact of the plasma power on the ion flux in collisional plasmas. The ion flux was found not to change considerably under the conditions where the deposited material undergoes a transition from the amorphous to the microcrystalline silicon phase; for solar-grade material, an ion-to-Si deposition flux of ?0.30 has been determined. As an upper-estimation of the ion energy, a mean ion energy of ?19 eV has been measured under low-pressure conditions (<1 mbar) by means of a retarding field energy analyzer. Combining this upper-estimate with an ion per deposited Si atom ratio of ?0.30, it is concluded that less than 6 eV is available per deposited Si atom. The addition of a small amount of SiH{sub 4} to an H{sub 2} plasma resulted in an increase of the ion flux by about 30% for higher power values, whereas the electron density, deduced from optical emission spectroscopy analysis, decreased. The electron temperature, also deduced from optical emission spectroscopy analysis, reveals a slight decrease with power. Although the dominant ion in the HPD regime is SiH{sub 3}{sup +}, i.e., a change from H{sub 3}{sup +} in pure hydrogen HPD conditions, the measured larger ion loss can be explained by assuming steeper electron density profiles. These results, therefore, confirm the results reported so far: the ion-to-Si deposition flux is relatively large but has neither influence on the microcrystalline silicon film properties nor on the phase transition. Possible explanations are the reported high atomic hydrogen to deposition flux ratio, mitigating the detrimental effects of an excessive ion flux.

Bronneberg, A. C.; Kang, X.; Palmans, J.; Janssen, P. H. J.; Lorne, T. [Applied Physics Department, Eindhoven University of Technology, P.O. Box 513, 5600MB Eindhoven (Netherlands)] [Applied Physics Department, Eindhoven University of Technology, P.O. Box 513, 5600MB Eindhoven (Netherlands); Creatore, M. [Applied Physics Department, Eindhoven University of Technology, P.O. Box 513, 5600MB Eindhoven (Netherlands) [Applied Physics Department, Eindhoven University of Technology, P.O. Box 513, 5600MB Eindhoven (Netherlands); Solliance Solar Research, High Tech Campus 5, 5656AE Eindhoven (Netherlands); Sanden, M. C. M. van de [Applied Physics Department, Eindhoven University of Technology, P.O. Box 513, 5600MB Eindhoven (Netherlands); Dutch Institute for Fundamental Energy Research (DIFFER), P.O. Box 1207, 3430BE Nieuwegein (Netherlands)

2013-08-14T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage direct" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Ancillary service details: Voltage control  

SciTech Connect (OSTI)

Voltage control is accomplished by managing reactive power on an alternating-current power system. Reactive power can be produced and absorbed by both generation and transmission equipment. Reactive-power devices differ substantially in the magnitude and speed of response and in their capital costs. System operators, transmission owners, generators, customers, power marketers, and government regulators need to pay close attention to voltage control as they restructure the U.S. electricity industry. Voltage control can affect reliability and commerce in three ways: (1) Voltages must be maintained within an acceptable range for both customer and power-system equipment to function properly. (2) The movement of reactive power consumes transmission resources, which limits the ability to move real power and worsens congestion. (3) The movement of reactive power results in real-power losses. When generators are required to supply excessive amounts of reactive power, their real-power production must be curtailed. These opportunity costs are not currently compensated for in most regions. Current tariffs are based on embedded costs. These embedded-cost tariffs average about $0.51/MWh, equivalent to $1.5 billion annually for the United States as a whole. Although this cost is low when compared with the cost of energy, it still aggregates to a significant amount of money. This report takes a basic look at why the power system requires reactive power (an appendix explains the fundamentals of real and reactive power). The report then examines the various types of generation and transmission resources used to supply reactive power and to control voltage. Finally it discusses how these resources are deployed and paid for in several reliability regions around the country. As the U.S. electricity industry is restructured, the generation, transmission, and system-control equipment and functions that maintain voltages within the appropriate ranges are being deintegrated.

Kirby, B.; Hirst, E.

1997-12-01T23:59:59.000Z

322

High efficiency direct detection of ions from resonance ionization of sputtered atoms  

DOE Patents [OSTI]

A method and apparatus are provided for trace and other quantitative analysis with high efficiency of a component in a sample, with the analysis involving the removal by ion or other bombardment of a small quantity of ion and neutral atom groups from the sample, the conversion of selected neutral atom groups to photoions by laser initiated resonance ionization spectroscopy, the selective deflection of the photoions for separation from original ion group emanating from the sample, and the detection of the photoions as a measure of the quantity of the component. In some embodiments, the original ion group is accelerated prior to the RIS step for separation purposes. Noise and other interference are reduced by shielding the detector from primary and secondary ions and deflecting the photoions sufficiently to avoid the primary and secondary ions.

Gruen, D.M.; Pellin, M.J.; Young, C.E.

1985-01-16T23:59:59.000Z

323

Rationale for continuing R&D in direct coal conversion to produce high quality transportation fuels  

SciTech Connect (OSTI)

Liquid hydrocarbon fuels will continue to play a significant role in the transportation sector in the future of both the world and the United States because of the their convenience, high energy density, and vast existing infrastructure. At present the U.S. consumes about 26% of the world supply of petroleum, but this situation is expected to change because of declining domestic production and increasing competition for imports by developing overseas economies. A scenario and time frame are developed in which declining world resources will generate a shortfall in petroleum supply that can be alleviated in part by utilizing the abundant domestic coal resource base. Continued R&D in coal conversion technology is expected to significantly reduce costs so that synfuels can compete economically at a much earlier date than previously forecast.

Srivastava, R.; McIlvried, H.G. [Burns and Roe Services Co., Pittsburgh, PA (United States); Gray, D.; Klunder, E.B.

1995-12-31T23:59:59.000Z

324

Consideration of critically when directly disposing highly enriched spent nuclear fuel in unsaturated tuff: Bounding estimates  

SciTech Connect (OSTI)

This report presents one of 2 approaches (bounding calculations) which were used in a 1994 study to examine the possibility of a criticality in a repository. Bounding probabilities, although rough, point to the difficulty of creating conditions under which a critical mass could be assembled (container corrosion, separation of neutron absorbers from fissile material, collapse or precipitation of fissile material) and how significant the geochemical and hydrologic phenomena are. The study could not conceive of a mechanism consistent with conditions under which an atomic explosion could occur. Should a criticality occur in or near a container in the future, boundary consequence calculations showed that fissions from one critical event (<10{sup 20} fissions, if similar to aqueous and metal accidents and experiments) are quite small compared to the amount of fissions represented by the spent fuel itself. If it is assumed that the containers necessary to hold the highly enriched spent fuel went critical once per day for 1 million years, creating an energy release of about 10{sup 20} fissions, the number of fissions equals about 10{sup 28}, which corresponds to only 1% of the fission inventory in a repository containing 70,000 metric tons of heavy metal, the expected size for the proposed repository at Yucca Mountain, Nevada.

Rechard, R.P.; Tierney, M.S.; Sanchez, L.C.; Martell, M.-A.

1996-05-01T23:59:59.000Z

325

Use of High?Power Combiners and Fast Directional Switches in ECRH Systems  

Science Journals Connector (OSTI)

The new generation of compact devices for the combination and the fast switching of high?power millimeter?wave beams [1] for Electron Cyclotron Heating (ECH) gives the possibility to switch the power (in tens of microseconds) between two lines (or two ECH launchers even modulating it between them) and combine two gyrotron sources (or in principle even more) in one single transmission line for doubling the transmitted power. This is useful in many respects in order to: 1) ?double the efficiency in modulated EC for neoclassical Tearing Modes (NTM) stabilization 2) avoid to switch?off gyrotrons in conventional (slow) switching 3) electronically control the power sharing between different applications (heating/current?drive or NTM stabilization) 4) upgrade the existing ECH systems to twice the power without adding complete transmission lines and launchers 5) test components at a power doubled with respect to the power capability of the available sources. This opens the way to the development of a more effective “active” real?time control of the ECRH power routing and generally to more flexible and powerful ECH systems. The development of different devices and the advantages for (and in view of) ITER are addressed.

A. Bruschi; W. Kasparek; V. Erckmann; M. Petelin; W. Bin; O. D’Arcangelo; L. Lubyako; V. Muzzini; B. Plaum

2009-01-01T23:59:59.000Z

326

Optical crystal based devices for current and voltage measurement  

SciTech Connect (OSTI)

A prerequisite for safe, stable operation of an electric power system is accurate, reliable measurement of the system parameters, in particular, current and voltage. Traditionally this has been achieved on High Voltage (HV) systems by expensive, bulky iron-cored current transformers (CTs) and capacitor voltage transformers (VTs). Both these devices are increasingly coming under review in modern power systems due to their cost, safety implications for personnel and surrounding plant if failure occurs, installation time and indeed substation land requirements. This paper describes novel designs for magneto-optic and electro-optic crystal sensors providing potentially separate and combined current and voltage measurement. The results of testing programs are presented and details of the work associated with field trials given.

Cruden, A.; Richardson, Z.J.; McDonald, J.R.; Andonovic, I. [Univ. of Strathclyde (United Kingdom)] [Univ. of Strathclyde (United Kingdom)

1995-07-01T23:59:59.000Z

327

Voltage Regulator Chip: Power Supplies on a Chip  

SciTech Connect (OSTI)

ADEPT Project: CPES at Virginia Tech is finding ways to save real estate on a computer's motherboard that could be used for other critical functions. Every computer processor today contains a voltage regulator that automatically maintains a constant level of electricity entering the device. These regulators contain bulky components and take up about 30% of a computer's motherboard. CPES at Virginia Tech is developing a voltage regulator that uses semiconductors made of gallium nitride on silicon (GaN-on-Si) and high-frequency soft magnetic material. These materials are integrated on a small, 3D chip that can handle the same amount of power as traditional voltage regulators at 1/10 the size and with improved efficiency. The small size also frees up to 90% of the motherboard space occupied by current voltage regulators.

None

2010-09-01T23:59:59.000Z

328

Current vs. Voltage Feedback Amplifiers  

E-Print Network [OSTI]

?' In most applications, the differences between current feedback (CFB) and voltage feedback (VFB) are not apparent. Today's CFB and VFB amplifiers have comparable performance, but there are cer- tain unique Performance · Feedback Freedom Aside from the well-known attribute of CFB amplifiers, gain

Lanterman, Aaron

329

Low voltage operation of plasma focus  

Science Journals Connector (OSTI)

Plasma foci of compact sizes and operating with low energies (from tens of joules to few hundred joules) have found application in recent years and have attracted plasma-physics scientists and engineers for research in this direction. We are presenting a low energy and miniature plasma focus which operates from a capacitor bank of 8.4 ? ? F capacity charged at 4.2–4.3 kV and delivering approximately 52 kA peak current at approximately 60 nH calculated circuit inductance. The total circuit inductance includes the plasma focusinductance. The reported plasma focus operates at the lowest voltage among all reported plasma foci so far. Moreover the cost of capacitor bank used for plasma focus is nearly 20 U.S. dollars making it very cheap. At low voltage operation of plasma focus the initial breakdown mechanism becomes important for operation of plasma focus. The quartz glass tube is used as insulator and breakdown initiation is done on its surface. The total energy of the plasma focus is approximately 75 J. The plasma focus system is made compact and the switching of capacitor bank energy is done by manual operating switch. The focus is operated with hydrogen and deuterium filled at 1–2 mbar.

Rohit Shukla; S. K. Sharma; P. Banerjee; R. Das; P. Deb; T. Prabahar; B. K. Das; B. Adhikary; A. Shyam

2010-01-01T23:59:59.000Z

330

Field test of two high-pressure, direct-contact downhole steam generators. Volume I. Air/diesel system  

SciTech Connect (OSTI)

As a part of the Project DEEP STEAM to develop technology to more efficiently utilize steam for the recovery of heavy oil from deep reservoirs, a field test of a downhole steam generator (DSG) was performed. The DSG burned No. 2 diesel fuel in air and was a direct-contact, high pressure device which mixed the steam with the combustion products and injected the resulting mixture directly into the oil reservoir. The objectives of the test program included demonstration of long-term operation of a DSG, development of operational methods, assessment of the effects of the steam/combustion gases on the reservoir and comparison of this air/diesel DSG with an adjacent oxygen/diesel direct contact generator. Downhole operation of the air/diesel DSG was started in June 1981 and was terminated in late February 1982. During this period two units were placed downhole with the first operating for about 20 days. It was removed, the support systems were slightly modified, and the second one was operated for 106 days. During this latter interval the generator operated for 70% of the time with surface air compressor problems the primary source of the down time. Thermal contact, as evidenced by a temperature increase in the production well casing gases, and an oil production increase were measured in one of the four wells in the air/diesel pattern. Reservoir scrubbing of carbon monoxide was observed, but no conclusive data on scrubbing of SO/sub x/ and NO/sub x/ were obtained. Corrosion of the DSG combustor walls and some other parts of the downhole package were noted. Metallurgical studies have been completed and recommendations made for other materials that are expected to better withstand the downhole combustion environment. 39 figures, 8 tables.

Marshall, B.W.

1983-05-01T23:59:59.000Z

331

On the scaling of rf and dc self-bias voltages with pressure in electronegative capacitively coupled plasmas  

SciTech Connect (OSTI)

Higher gas densities and lower diffusion losses at higher operating pressures typically lead to increased charged species densities (and hence flux) for a constant power deposition in capacitively coupled plasmas (CCP). As a result, one would expect that the bias radio-frequency (rf) voltage required to deposit a given power in a CCP reactor decreases with increasing operating pressure. These observations may not hold true in multiple frequency CCPs, commonly used for dielectric etching in microelectronics fabrication, due to nonlinear interactions between the rf sources. Wafer-based measurements of the rf and self-generated direct current (dc) bias voltages in a dual-frequency capacitively coupled electronegative plasma were made, which indicate that the rf and dc voltages vary nonmonotonically with pressure. These experimental results are presented in this paper and a computational plasma model is used to explain the experimental observations for varying 60 MHz and 13 MHz powers in the Ar/CF{sub 4}/CHF{sub 3} plasma over a pressure range of 25 to 400 mTorr. The authors found that while the ion density increases with pressure, the increase is most dominant near the electrode with the high frequency source (60 MHz). The rf and dc bias voltages are ultimately influenced by both charged species density magnitudes and spatial profiles.

Agarwal, Ankur; Dorf, Leonid; Rauf, Shahid; Collins, Ken [Applied Materials Inc., 974 E. Arques Avenue, M/S 81312, Sunnyvale, California 94085 (United States)

2012-03-15T23:59:59.000Z

332

Automatic Voltage Control of Electrical Systems  

Science Journals Connector (OSTI)

... to have complete automatic voltage regulation and it also has supervisory control for its main substations. By a careful application of automatically controlled regulators it is shown that the voltage ...

1934-01-20T23:59:59.000Z

333

Implications of Pulser Voltage Ripple  

SciTech Connect (OSTI)

In a recent set of measurements obtained by G. Kamin, W. Manning, A. Molvik, and J. Sullivan, the voltage waveform of the diode pulser had a ripple of approximately {+-}1.3% of the 65 kV flattop voltage, and the beam current had a larger corresponding ripple of approximately {+-}8.4% of the 1.5 mA average current at the location of the second Faraday cup, approximately 1.9 m downstream from the ion source. The period of the ripple was about 1 {mu}s. It was initially unclear whether this large current ripple was in fact a true measurement of the current or a spurious measurement of noise produced by the pulser electronics. The purpose of this note is to provide simulations which closely match the experimental results and thereby corroborate the physical nature of those measurements, and to provide predictions of the amplitude of the current ripples as they propagate to the end of linear transport section. Additionally analytic estimates are obtained which lend some insight into the nature of the current fluctuations and to provide an estimate of what the maximum amplitude of the current fluctuations are expected to be, and conversely what initial ripple in the voltage source is allowed, given a smaller acceptable tolerance on the line charge density.

Barnard, J J

2011-12-21T23:59:59.000Z

334

Determination of Depleted Uranium in Urine via Isotope Ratio Measurements Using Large-Bore Direct Injection High Efficiency Nebulizer–Inductively Coupled Plasma Mass Spectrometry  

Science Journals Connector (OSTI)

Inductively coupled plasma mass spectrometry (ICP-MS), coupled with a large-bore direct injection high efficiency nebulizer (LB-DIHEN), was utilized to determine the concentration and...

Westphal, Craig S; McLean, John A; Hakspiel, Shelly J; Jackson, William E; McClain, David E; Montaser, Akbar

2004-01-01T23:59:59.000Z

335

Onset voltage of corona on coated conductors  

SciTech Connect (OSTI)

This paper is aimed for investigating the effect of surface coating on the positive and negative onset voltages of corona from stressed conductor as a pre-requisite for onset-voltage calculation. The electric field is accurately calculated by the charge simulation technique. The calculated onset voltages agreed satisfactorily with those measured experimentally for bare conductors. The effect of coating-layer thickness and permittivity as well as conductor radius and height on the onset-voltage values is discussed.

Abdel-Salam, M. [Assiut Univ. (Egypt). Electrical Engineering Dept.; Abo-Shal, Y. [SCECO-East, Dammam (Saudi Arabia). Electrical Engineering Div.

1995-12-31T23:59:59.000Z

336

Improving the low voltage ride through of doubly fed induction generator during intermittent voltage source converter faults  

Science Journals Connector (OSTI)

The impact of different voltage source converter (VSC) faults on the low voltage ride through (LVRT) capability of the doubly fed induction generator (DFIG) is also investigated. Faults such as fire-through of the VSC switches and short circuit across the DC-link capacitor are considered in this paper. The impact of internal VSC faults when they occur within the grid side converter (GSC) and rotor side converter is investigated. A proper static synchronous compensator (STATCOM) controller to mitigate the effects of these faults is proposed. The DFIG compliance with numerous and recently released LVRT grid codes under these faults with and without the STATCOM is examined and compared. Simulation results indicate that these types of faults have a severe impact on the DFIG voltage profile especially when these faults occur in the GSC. This is attributed to the fact that the GSC directly regulates the point of common coupling (PCC) voltage. Moreover the proposed controller is capable of bringing the voltage profile at the PCC to the nominal steady state level and hence maintaining the connection of the wind turbine during the various studied faults.

H. R. Pota

2013-01-01T23:59:59.000Z

337

Method and apparatus for digitally based high speed x-ray spectrometer for direct coupled use with continuous discharge preamplifiers  

DOE Patents [OSTI]

A high speed, digitally based, signal processing system which accepts directly coupled input data from a detector with a continuous discharge type preamplifier and produces a spectral analysis of the x-rays illuminating the detector. The system's principal elements are an analog signal conditioning section, a combinatorial logic section which implements digital triangular filtering and pileup inspection, and a microprocessor which accepts values captured by the logic section and uses them to compute x-ray energy values. Operating without pole-zero correction, the system achieves high resolution by capturing, in conjunction with each peak value from the digital filter, an associated value of the unfiltered signal, and using this latter signal to correct the former for errors which arise from its local slope terms. This correction greatly reduces both energy resolution degradation and peak centroid shifting in the output spectrum as a function of input count rate. When the noise of this correction is excessive, a modification allows two filtered averages of the signal to be captured and a corrected peak amplitude computed therefrom.

Warburton, William K. (1300 Mills St., Menlo Park, CA 94025)

1998-01-01T23:59:59.000Z

338

Method and apparatus for digitally based high speed x-ray spectrometer for direct coupled use with continuous discharge preamplifiers  

DOE Patents [OSTI]

A high speed, digitally based, signal processing system is disclosed which accepts directly coupled input data from a detector with a continuous discharge type preamplifier and produces a spectral analysis of the x-rays illuminating the detector. The system`s principal elements are an analog signal conditioning section, a combinatorial logic section which implements digital triangular filtering and pileup inspection, and a microprocessor which accepts values captured by the logic section and uses them to compute x-ray energy values. Operating without pole-zero correction, the system achieves high resolution by capturing, in conjunction with each peak value from the digital filter, an associated value of the unfiltered signal, and using this latter signal to correct the former for errors which arise from its local slope terms. This correction greatly reduces both energy resolution degradation and peak centroid shifting in the output spectrum as a function of input count rate. When the noise of this correction is excessive, a modification allows two filtered averages of the signal to be captured and a corrected peak amplitude computed therefrom. 14 figs.

Warburton, W.K.

1998-06-30T23:59:59.000Z

339

Surface and Structural Stabilities of Carbon Additives in High...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Structural Stabilities of Carbon Additives in High Voltage Lithium Ion Batteries. Surface and Structural Stabilities of Carbon Additives in High Voltage Lithium Ion Batteries....

340

Chapter 17. High-Voltage Systems and Dielectric Materials High-Voltage Systems and Dielectric Materials  

E-Print Network [OSTI]

aromatic, naphthenic, and paraffinic molecules with complex molecular structures. With the advancement

Note: This page contains sample records for the topic "high voltage direct" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Faceted growth of primary Al{sub 2}Cu crystals during directional solidification in high magnetic field  

SciTech Connect (OSTI)

The high magnetic field is widely used to modify the crystal morphology. In this work, the effect of the magnetic field on growing behavior of faceted crystals in the Al-40 wt. %Cu alloy was investigated using directional solidification technique. It was found that the faceted growth of primary Al{sub 2}Cu phase was degraded and the primary spacing was reduced upon applying the magnetic field. Additionally, the length of the mushy zone first decreased and then increased with increase of the magnetic field intensity. The quantitative analysis reveals that the shear stress induced by the fluid motion is insufficient to break the atom bonds at the solid-liquid interface. However, both of the thermoelectric magnetic convection (TEMC) and the thermoelectric magnetic force (TEMF) cause dendrites to fracture and reduce the primary spacing. The two effects also weaken the faceting growth. Moreover, the instability of the solid-liquid interface is generated by the TEMF, which further leads to degrade the faceted growth. The length of mushy zone was changed by the TEMC and reached the minimum in the magnetic field of 0.5 T, which is in good agreement with the predicted value (0.83 T)

Li, Chuanjun; Ren, Zhongming; Shen, Yu [School of Materials Science and Engineering, Shanghai University, Shanghai 200072 (China)] [School of Materials Science and Engineering, Shanghai University, Shanghai 200072 (China); Wang, Qiuliang; Dai, Yinming; Wang, Hui [Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing 100190 (China)] [Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing 100190 (China)

2013-10-21T23:59:59.000Z

342

Direct formation of supermassive black holes in metal-enriched gas at the heart of high-redshift galaxy mergers  

E-Print Network [OSTI]

We present novel 3D multi-scale SPH simulations of gas-rich galaxy mergers between the most massive galaxies at $z \\sim 8 - 10$, designed to scrutinize the direct collapse formation scenario for massive black hole seeds proposed in \\citet{mayer+10}. The simulations achieve a resolution of 0.1 pc, and include both metallicity-dependent optically-thin cooling and a model for thermal balance at high optical depth. We consider different formulations of the SPH hydrodynamical equations, including thermal and metal diffusion. When the two merging galaxy cores collide, gas infall produces a compact, optically thick nuclear disk with densities exceeding $10^{-10}$ g cm$^3$. The disk rapidly accretes higher angular momentum gas from its surroundings reaching $\\sim 5$ pc and a mass of $\\gtrsim 10^9$ $M_{\\odot}$ in only a few $10^4$ yr. Outside $\\gtrsim 2$ pc it fragments into massive clumps. Instead, supersonic turbulence prevents fragmentation in the inner parsec region, which remains warm ($\\sim 3000-6000$ K) and dev...

Mayer, Lucio; Bonoli, Silvia; Quinn, Thomas; Roskar, Rok; Shen, Sijing; Wadsley, James

2014-01-01T23:59:59.000Z

343

Local Voltage Support from Distributed Energy Resources to Prevent Air Conditioner Motor Stalling  

SciTech Connect (OSTI)

Microgrid voltage collapse often happens when there is a high percentage of low inertia air-conditioning (AC) motors in the power systems. The stalling of the AC motors results in Fault Induced Delayed Voltage Recovery (FIDVR). A hybrid load model including typical building loads, AC motor loads, and other induction motor loads is built to simulate the motoring stalling phenomena. Furthermore, distributed energy resources (DE) with local voltage support capability are utilized to boost the local bus voltage during a fault, and prevent the motor stalling. The simulation results are presented. The analysis of the simulation results show that local voltage support from multiple DEs can effectively and economically solve the microgrid voltage collapse problem.

Baone, Chaitanya A [ORNL] [ORNL; Xu, Yan [ORNL] [ORNL; Kueck, John D [ORNL] [ORNL

2010-01-01T23:59:59.000Z

344

High Temperature, High Voltage Fully Integrated Gate Driver Circuit  

Broader source: Energy.gov [DOE]

2010 DOE Vehicle Technologies and Hydrogen Programs Annual Merit Review and Peer Evaluation Meeting, June 7-11, 2010 -- Washington D.C.

345

High Temperature, High Voltage Fully Integrated Gate Driver Circuit  

Broader source: Energy.gov [DOE]

2009 DOE Hydrogen Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting, May 18-22, 2009 -- Washington D.C.

346

A Static Pattern-Independent Technique for Power Grid Voltage Integrity Verification  

E-Print Network [OSTI]

A Static Pattern-Independent Technique for Power Grid Voltage Integrity Verification Dionysios Design verification must include the power grid. Checking that the voltage on the power grid does) the obviously large size of the power grids for modern high-performance chips, and ii) the difficulty of setting

Najm, Farid N.

347

A Static PatternIndependent Technique for Power Grid Voltage Integrity Verification #  

E-Print Network [OSTI]

A Static Pattern­Independent Technique for Power Grid Voltage Integrity Verification # Dionysios Design verification must include the power grid. Checking that the voltage on the power grid does) the obviously large size of the power grids for modern high­performance chips, and ii) the di#culty of setting

Najm, Farid N.

348

Reactive power management of distribution networks with wind generation for improving voltage stability  

E-Print Network [OSTI]

Reactive power management of distribution networks with wind generation for improving voltage February 2013 Available online Keywords: Composite load Distributed generation D-STATCOM Q with distributed wind generation. Firstly, the impact of high wind penetration on the static voltage stability

Pota, Himanshu Roy

349

Definition: Operating Voltage | Open Energy Information  

Open Energy Info (EERE)

Voltage Voltage Jump to: navigation, search Dictionary.png Operating Voltage The voltage level by which an electrical system is designated and to which certain operating characteristics of the system are related; also, the effective (root-mean-square) potential difference between any two conductors or between a conductor and the ground. The actual voltage of the circuit may vary somewhat above or below this value.[1] Related Terms system References ↑ Glossary of Terms Used in Reliability Standards An LikeLike UnlikeLike You like this.Sign Up to see what your friends like. inline Glossary Definition Retrieved from "http://en.openei.org/w/index.php?title=Definition:Operating_Voltage&oldid=480559" Categories: Definitions ISGAN Definitions What links here Related changes

350

Wind Power Plant Voltage Stability Evaluation: Preprint  

SciTech Connect (OSTI)

Voltage stability refers to the ability of a power system to maintain steady voltages at all buses in the system after being subjected to a disturbance from a given initial operating condition. Voltage stability depends on a power system's ability to maintain and/or restore equilibrium between load demand and supply. Instability that may result occurs in the form of a progressive fall or rise of voltages of some buses. Possible outcomes of voltage instability are the loss of load in an area or tripped transmission lines and other elements by their protective systems, which may lead to cascading outages. The loss of synchronism of some generators may result from these outages or from operating conditions that violate a synchronous generator's field current limit, or in the case of variable speed wind turbine generator, the current limits of power switches. This paper investigates the impact of wind power plants on power system voltage stability by using synchrophasor measurements.

Muljadi, E.; Zhang, Y. C.

2014-09-01T23:59:59.000Z

351

Field test of two high-pressure direct-contact downhole steam generators. Volume II. Oxygen/diesel system  

SciTech Connect (OSTI)

A field test of an oxygen/diesel fuel, direct contact steam generator has been completed. The field test, which was a part of Project DEEP STEAM and was sponsored by the US Department of Energy, involved the thermal stimulation of a well pattern in the Tar Zone of the Wilmington Oil Field. The activity was carried out in cooperation with the City of Long Beach and the Long Beach Oil Development Company. The steam generator was operated at ground level, with the steam and combustion products delivered to the reservoir through 2022 feet of calcium-silicate insulated tubing. The objectives of the test included demonstrations of safety, operational ease, reliability and lifetime; investigations of reservoir response, environmental impact, and economics; and comparison of those points with a second generator that used air rather than oxygen. The test was extensively instrumented to provide the required data. Excluding interruptions not attributable to the oxygen/diesel system, steam was injected 78% of the time. System lifetime was limited by the combustor, which required some parts replacement every 2 to 3 weeks. For the conditions of this particular test, the use of trucked-in LOX resulted in liess expense than did the production of the equivalent amount of high pressure air using on site compressors. No statistically significant production change in the eight-acre oxygen system well pattern occurred during the test, nor were any adverse effects on the reservoir character detected. Gas analyses during the field test showed very low levels of SOX (less than or equal to 1 ppM) in the generator gaseous effluent. The SOX and NOX data did not permit any conclusion to be drawn regarding reservoir scrubbing. Appreciable levels of CO (less than or equal to 5%) were measured at the generator, and in this case produced-gas analyses showed evidence of significant gas scrubbing. 64 figures, 10 tables.

Moreno, J.B.

1983-07-01T23:59:59.000Z

352

Alternative Energy Development and China's Energy Future  

E-Print Network [OSTI]

high voltage direct current (HVDC) transmission which canhigh voltage direct current (HVDC) transmission, an increase

Zheng, Nina

2012-01-01T23:59:59.000Z

353

Group 3: Humidity, Temperature, and Voltage (Presentation)  

SciTech Connect (OSTI)

Group 3 is chartered to develop accelerated stress tests that can be used as comparative predictors of module lifetime versus stresses associated with humidity, temperature and voltage.

Wohlgemuth, J.

2013-05-01T23:59:59.000Z

354

Variable Voltage Substation Electric Fire and Emergency Response  

Broader source: Energy.gov [DOE]

Variable Voltage Substation Electric Fire and Emergency Response My question is from an emergency response perspective. You stated that it took ~ ½ for electricians to de-energize the electrical components before firefighters were allowed in to fight the fire. This delay causes more damage to equipment and potential propagation of the fire. Is there not a “master” breaker or switch? You’ve brought up a very good point. It gave me a good opportunity to discuss this with our Facilities Department and get a better understanding of the infrastructure upgrade plans. The direct answer to your question is “Yes, but…” Yes, there are “master” breakers and switches, but we can’t control them remotely. SLAC’s AC electrical distribution system at present is manual breakers – we have not installed the infrastructure to remotely control them (except see below). We recently underwent an upgrade to our Master Substation that will allow us to remotely control some high voltage breakers in the future, but we aren’t there yet. We do recognize the value in having this capability (and more importantly, our vulnerability in NOT having it), and have begun the preliminary planning to make this happen. One issue were are working on is cyber security for the power distribution networked infrastructure. Before we install the capability to remotely control the main electrical breakers, we are planning the infrastructure with our Information Technologies organization to ensure we have a robust secure network that is protected from unauthorized access. Once the cyber security issues are addressed and funded, we’re probably 5-10 years out from having remote operation capability due to limited resources to fund and install the infrastructure. Having said the above, we do have the capability of remotely opening the VVS Secondary Main Breakers – the ones that send power to the modulator distribution breakers - from our control room. Those breakers are integral parts of our safety systems in that interlock violation causes the breakers to open and remove power to the klystrons. But everything else is manual only. That remote operation capability would not have helped us in this case, as the VVS Secondary Main Breaker was the one that fried. We needed to open the breaker upstream of the VVS. Thanks for your interest. Let me know if I can provide further information.

355

A novel voltage and frequency controller for standalone DFIG based Wind Energy Conversion System  

Science Journals Connector (OSTI)

Abstract This paper presents a new speed-sensorless control strategy for a stand-alone doubly-fed induction generator supplying energy to an isolated load. The method is based on the root mean square (rms) detection scheme. The generated stator voltage is controlled via rotor currents. Amplitude of stator voltage and its frequency are controlled simultaneously. The output signals from the voltage controllers are the reference signals for the rotor current amplitude and frequency of the stator voltage is regulated with the help of frequency control loop. This developed direct voltage control method is applicable for both the balanced and unbalanced load and also for standalone and grid connected mode. The control pulses for the rotor side converter is supplied by the hysteresis controller which is operated on the error signal calculated between actual and reference rotor currents. This paper also provides the brief idea about the voltage and frequency control on modern Autonomous DFIG based Wind Energy Systems via single phase mathematical model of standalone DFIG system. A short state-of-the-art review on mechanical position/speed sensorless control schemes for autonomous DFIG based \\{WESs\\} is presented, which helps the present researcher and students working in this area. These include stator flux oriented control techniques; direct voltage control techniques; MARS observer based techniques for autonomous DFIG-based variable-speed WESs. Simulation results obtained from a 2MVA DFIG system, prototype in MATLab/Simulink, are presented and discussed in this paper.

Rishabh Dev Shukla; Ramesh Kumar Tripathi

2014-01-01T23:59:59.000Z

356

Strain-optic voltage monitor wherein strain causes a change in the optical absorption of a crystalline material  

DOE Patents [OSTI]

A voltage monitor which uses the shift in absorption edge of crystalline material to measure strain resulting from electric field-induced deformation of piezoelectric or electrostrictive material, providing a simple and accurate means for measuring voltage applied either by direct contact with the crystalline material or by subjecting the material to an electric field.

Weiss, Jonathan D. (Albuquerque, NM)

1997-01-01T23:59:59.000Z

357

Vanadium Mesoporous Silica Catalyst Prepared by Direct Synthesis as High Performing Catalyst in Oxidative Dehydrogenation of n-Butane  

Science Journals Connector (OSTI)

The catalytic oxidative dehydrogenation (ODH) of light alkanes has great potential to be used for production of alkenes instead classically used dehydrogenation. We report successful direct synthesis of vanadi...

Michal Setni?ka; Pavel ?i?manec; Roman Bulánek; Arnošt Zukal…

2014-01-01T23:59:59.000Z

358

High-dimensionality 13C direct-detected NMR experiments for the automatic assignment of intrinsically disordered proteins  

Science Journals Connector (OSTI)

We present three novel exclusively heteronuclear 5D 13C direct-detected NMR experiments, namely (HN-flipN)CONCACON, (HCA)CONCACON and (H)CACON(CA)CON, designed for easy sequence-specific resonance assignment of i...

Wolfgang Bermel; Isabella C. Felli; Leonardo Gonnelli…

2013-12-01T23:59:59.000Z

359

Method for high-volume sequencing of nucleic acids: random and directed priming with libraries of oligonucleotides  

DOE Patents [OSTI]

Random and directed priming methods for determining nucleotide sequences by enzymatic sequencing techniques, using libraries of primers of lengths 8, 9 or 10 bases, are disclosed. These methods permit direct sequencing of nucleic acids as large as 45,000 base pairs or larger without the necessity for subcloning. Individual primers are used repeatedly to prime sequence reactions in many different nucleic acid molecules. Libraries containing as few as 10,000 octamers, 14,200 nonamers, or 44,000 decamers would have the capacity to determine the sequence of almost any cosmid DNA. Random priming with a fixed set of primers from a smaller library can also be used to initiate the sequencing of individual nucleic acid molecules, with the sequence being completed by directed priming with primers from the library. In contrast to random cloning techniques, a combined random and directed priming strategy is far more efficient.

Studier, F. William (Stony Brook, NY)

1995-04-18T23:59:59.000Z

360

High resolution biomedical imaging system with direct detection of x-rays via a charge coupled device  

DOE Patents [OSTI]

An imaging system is provided for direct detection of x-rays from an irradiated biological tissue. The imaging system includes an energy source for emitting x-rays toward the biological tissue and a charge coupled device (CCD) located immediately adjacent the biological tissue and arranged transverse to the direction of irradiation along which the x-rays travel. The CCD directly receives and detects the x-rays after passing through the biological tissue. The CCD is divided into a matrix of cells, each of which individually stores a count of x-rays directly detected by the cell. The imaging system further includes a pattern generator electrically coupled to the CCD for reading a count from each cell. A display device is provided for displaying an image representative of the count read by the pattern generator from the cells of the CCD. 13 figs.

Atac, M.; McKay, T.A.

1998-04-21T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage direct" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

High resolution biomedical imaging system with direct detection of x-rays via a charge coupled device  

DOE Patents [OSTI]

An imaging system is provided for direct detection of x-rays from an irradiated biological tissue. The imaging system includes an energy source for emitting x-rays toward the biological tissue and a charge coupled device (CCD) located immediately adjacent the biological tissue and arranged transverse to the direction of irradiation along which the x-rays travel. The CCD directly receives and detects the x-rays after passing through the biological tissue. The CCD is divided into a matrix of cells, each of which individually stores a count of x-rays directly detected by the cell. The imaging system further includes a pattern generator electrically coupled to the CCD for reading a count from each cell. A display device is provided for displaying an image representative of the count read by the pattern generator from the cells of the CCD.

Atac, Muzaffer (Wheaton, IL); McKay, Timothy A. (Ann Arbor, MI)

1998-01-01T23:59:59.000Z

362

Non-Directed Line-of-Sight Visible Light System providing High-Speed and Robustness to Ambient Light  

Science Journals Connector (OSTI)

We demonstrate the first optical wireless link operating in non-direct line-of-sight configuration over typical room distances, with data-rate up to 200 Mbit/s at acceptable...

Cossu, Giulio; Khalid, Amir M; Corsini, Raffaele; Ciaramella, Ernesto

363

Low Beam Voltage, 10 MW, L-Band Cluster Klystron  

SciTech Connect (OSTI)

Conceptual design of a multi-beam klystron (MBK) for possible ILC and Project X applications is presented. The chief distinction between this MBK design and existing 10-MW MBK's is the low operating voltage of 60 kV. There are at least four compelling reasons that justify development at this time of a low-voltage MBK, namely (1) no pulse transformer; (2) no oil tank for high-voltage components and for the tube socket; (3) no high-voltage cables; and (4) modulator would be a compact 60-kV IGBT switching circuit. The proposed klystron consists of four clusters containing six beams each. The tube has common input and output cavities for all 24 beams, and individual gain cavities for each cluster. A closely related optional configuration, also for a 10 MW tube, would involve four totally independent cavity clusters with four independent input cavities and four 2.5 MW output ports, all within a common magnetic circuit. This option has appeal because the output waveguides would not require a controlled atmosphere, and because it would be easier to achieve phase and amplitude stability as required in individual SC accelerator cavities.

Teryaev, V.; /Novosibirsk, IYF; Yakovlev, V.P.; /Fermilab; Kazakov, S.; /KEK, Tsukuba; Hirshfield, J.L.; /Yale U. /Omega-P, New Haven

2009-05-01T23:59:59.000Z

364

Analysis of Lightning-induced Voltages in Overhead Transmission Lines  

Science Journals Connector (OSTI)

Abstract In this work we study the coupling of lightning induced voltages in Overhead Transmission Lines .The study is led directly in the time domain with hold in account the effect of a finite conductivity of the soil. After discretization by the method so-called FDTD (Finite Difference Time Domain) of the lines equations excited by a lightning wave and the application in every node of the network in current and voltage, we deduct a equations system, of which the resolution permits us to deduct the induced electric quantities in every node of the network. In order to confirm our theoretical work, we present a set of applications that allows validating this study.

Mostefa. Boumaiza; Djamel. Labed

2014-01-01T23:59:59.000Z

365

DESIGN AND IMPLEMENTATION OF A FUZZY LOGIC-BASED VOLTAGE CONTROLLER FOR VOLTAGE REGULATION  

E-Print Network [OSTI]

1 DESIGN AND IMPLEMENTATION OF A FUZZY LOGIC-BASED VOLTAGE CONTROLLER FOR VOLTAGE REGULATION In this paper the design and implementation of a fuzzy logic-based controller is described for regulating the output voltage of a synchronous generator. An automated fuzzy logic-based control strategy is presented

LaMeres, Brock J.

366

Voltage regulation in linear induction accelerators  

DOE Patents [OSTI]

Improvement in voltage regulation in a Linear Induction Accelerator wherein a varistor, such as a metal oxide varistor, is placed in parallel with the beam accelerating cavity and the magnetic core. The non-linear properties of the varistor result in a more stable voltage across the beam accelerating cavity than with a conventional compensating resistance.

Parsons, William M. (Santa Fe, NM)

1992-01-01T23:59:59.000Z

367

Voltage regulation in linear induction accelerators  

DOE Patents [OSTI]

Improvement in voltage regulation in a linear induction accelerator wherein a varistor, such as a metal oxide varistor, is placed in parallel with the beam accelerating cavity and the magnetic core is disclosed. The non-linear properties of the varistor result in a more stable voltage across the beam accelerating cavity than with a conventional compensating resistance. 4 figs.

Parsons, W.M.

1992-12-29T23:59:59.000Z

368

NREL: Measurements and Characterization - Current Versus Voltage  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Current Versus Voltage Current Versus Voltage The National Renewable Energy Laboratory (NREL) Device Performance group uses current versus voltage (I-V) measurement systems to assess the main performance parameters for photovoltaic (PV) cells and modules. I-V measurement systems determine the output performance of devices, including: open-circuit voltage (Voc), short-circuit current (Isc), fill factor (FF), maximum power output of the device (Pmax), voltage at maximum power (Vmax), current at maximum power (Imax), and conversion efficiency of the device (η). Some I-V systems may also be used to perform dark I-V measurements to determine diode properties and series and shunt resistances. We use three I-V systems to measure performance of individual PV cells; and four for modules - two for measurements under simulated conditions; and

369

Non-contact current and voltage sensor  

DOE Patents [OSTI]

A detachable current and voltage sensor provides an isolated and convenient device to measure current passing through a conductor such as an AC branch circuit wire, as well as providing an indication of an electrostatic potential on the wire, which can be used to indicate the phase of the voltage on the wire, and optionally a magnitude of the voltage. The device includes a housing that contains the current and voltage sensors, which may be a ferrite cylinder with a hall effect sensor disposed in a gap along the circumference to measure current, or alternative a winding provided through the cylinder along its axis and a capacitive plate or wire disposed adjacent to, or within, the ferrite cylinder to provide the indication of the voltage.

Carpenter, Gary D; El-Essawy, Wael; Ferreira, Alexandre Peixoto; Keller, Thomas Walter; Rubio, Juan C; Schappert, Michael A

2014-03-25T23:59:59.000Z

370

Anisotropy and chemical composition of ultra-high energy cosmic rays using arrival directions measured by the Pierre Auger Observatory  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

The Pierre Auger Collaboration has reported evidence for anisotropy in the distribution of arrival directions of the cosmic rays with energies E > Eth = 5.5 x 1019 eV. These show a correlation with the distribution of nearby extragalactic objects, including an apparent excess around the direction of Centaurus A. If the particles responsible for these excesses at E > Eth are heavy nuclei with charge Z, the proton component of the sources should lead to excesses in the same regions at energies E/Z. We here report the lack of anisotropies in these directions at energies above Eth/Z (for illustrative values of Z = 6,13,26). If the anisotropies above Eth are due to nuclei with charge Z, and under reasonable assumptions about the acceleration process, these observations imply stringent constraints on the allowed proton fraction at the lower energies.

Abreu, P [Lisbon, IST; Aglietta, M [IFSI, Turin; Ahn, E J [Fermilab; Albuquerque, I F.M. [Sao Paulo U.; Allard, D [APC, Paris; Allekotte, I [Centro Atomico Bariloche; Allen, J [New York U.; Allison, P [Ohio State U.; Alvarez Castillo, J [Mexico U., ICN; Alvarez-Muniz, J [Santiago de Compostela U.; Ambrosio, M [Napoli Seconda U.; INFN, Naples; Nijmegen U., IMAPP

2011-06-17T23:59:59.000Z

371

The direct production of electron pairs by high-energy muons underground (148 m w.e.)  

Science Journals Connector (OSTI)

Direct production of electron pairs in thin iron targets by muons of mean energy 32.6 GeV was studied with a ... two or more electrons associated with each outgoing muon from the targets were selected and their energy

N. Chaudhuri; M. S. Sinha

1964-01-16T23:59:59.000Z

372

Low-voltage, low-power circuits for data communication systems  

E-Print Network [OSTI]

There are growing industrial demands for low-voltage supply and low-power consumption circuits and systems. This is especially true for very high integration level and very large scale integrated (VLSI) mixed-signal chips and system...

Chen, Mingdeng

2005-02-17T23:59:59.000Z

373

Application of evolutionary algorithms for the planning of urban distribution networks of medium voltage  

E-Print Network [OSTI]

Abstract—Currently, an important issue in power distribution is the need to optimize medium voltage (mv) networks serving urban areas. This paper shows how an evolutionary algorithm can be used as the basis for the type of efficient algorithm such optimization demands. The search for optimal network solution will be restricted to a graph defined from the urban map, so each graph branch represents a trench. The solution space (networks) is assumed with “loop feeder circuits”: networks with two electrical paths from the high voltage/medium voltage (hv/mv) substations to the customers. In the optimization process, the investment and loss load costs are considered taking into account the constraints of conductor capacities and voltage drop. The investment costs will take into account that some cables can be lying in the same trench. The process was applied for a Spanish city of 200 000 inhabitants. Index Terms—Evolutionary algorithm, medium voltage network planning, network design, urban distribution network. I.

unknown authors

2002-01-01T23:59:59.000Z

374

Anisotropy and chemical composition of ultra-high energy cosmic rays using arrival directions measured by the Pierre Auger Observatory  

SciTech Connect (OSTI)

The Pierre Auger Collaboration has reported evidence for anisotropy in the distribution of arrival directions of the cosmic rays with energies E > Eth = 5.5 x 1019 eV. These show a correlation with the distribution of nearby extragalactic objects, including an apparent excess around the direction of Centaurus A. If the particles responsible for these excesses at E > Eth are heavy nuclei with charge Z, the proton component of the sources should lead to excesses in the same regions at energies E/Z. We here report the lack of anisotropies in these directions at energies above Eth/Z (for illustrative values of Z = 6,13,26). If the anisotropies above Eth are due to nuclei with charge Z, and under reasonable assumptions about the acceleration process, these observations imply stringent constraints on the allowed proton fraction at the lower energies.

Abreu, P [Lisbon, IST; Aglietta, M [IFSI, Turin; Ahn, E J [Fermilab; Albuquerque, I F.M. [Sao Paulo U.; Allard, D [APC, Paris; Allekotte, I [Centro Atomico Bariloche; Allen, J [New York U.; Allison, P [Ohio State U.; Alvarez Castillo, J [Mexico U., ICN; Alvarez-Muniz, J [Santiago de Compostela U.; Ambrosio, M [Napoli Seconda U.; INFN, Naples; Nijmegen U., IMAPP

2011-06-17T23:59:59.000Z

375

Bonfire-safe low-voltage detonator  

DOE Patents [OSTI]

A column of explosive in a low-voltage detonator which makes it bonfire-safe includes a first layer of an explosive charge of CP, or a primary explosive, and a second layer of a secondary organic explosive charge, such as PETN, which has a degradation temperature lower than the autoignition temperature of the CP or primary explosives. The first layer is composed of a pair of increments disposed in a bore of a housing of the detonator in an ignition region of the explosive column and adjacent to and in contact with an electrical ignition device at one end of the bore. The second layer is composed of a plurality of increments disposed in the housing bore in a transition region of the explosive column next to and in contact with the first layer on a side opposite from the ignition device. The first layer is loaded under a sufficient high pressure, 25 to 40 kpsi, to achieve ignition, whereas the second layer is loaded under a sufficient low pressure, about 10 kpsi, to allow occurrence of DDT. Each increment of the first and second layers has an axial length-to-diameter ratio of one-half.

Lieberman, Morton L. (Albuquerque, NM)

1990-01-01T23:59:59.000Z

376

Effect of current compliance and voltage sweep rate on the resistive switching of HfO{sub 2}/ITO/Invar structure as measured by conductive atomic force microscopy  

SciTech Connect (OSTI)

The electrical characterization of HfO{sub 2}/ITO/Invar resistive switching memory structure was studied using conductive atomic force microscopy (AFM) with a semiconductor parameter analyzer, Agilent 4156C. The metal alloy Invar was used as the metal substrate to ensure good ohmic contact with the substrate holder of the AFM. A conductive Pt/Ir AFM tip was placed in direct contact with the HfO{sub 2} surface, such that it acted as the top electrode. Nanoscale current-voltage (I-V) characteristics of the HfO{sub 2}/ITO/Invar structure were measured by applying a ramp voltage through the conductive AFM tip at various current compliances and ramp voltage sweep rates. It was found that the resistance of the low resistance state (RLRS) decreased with increasing current compliance value, but resistance of high resistance state (RHRS) barely changed. However, both the RHRS and RLRS decreased as the voltage sweep rate increased. The reasons for this dependency on current compliance and voltage sweep rate are discussed.

Wu, You-Lin, E-mail: ylwu@ncnu.edu.tw; Liao, Chun-Wei [Department of Electrical Engineering, National Chi Nan University, Puli, Nantou, Taiwan (China); Ling, Jing-Jenn [Department of Applied Materials and Optoelectronic Engineering, National Chi Nan University, Puli, Nantou, Taiwan (China)

2014-06-16T23:59:59.000Z

377

Property:Nominal Voltage | Open Energy Information  

Open Energy Info (EERE)

Nominal Voltage Nominal Voltage Jump to: navigation, search Property Name Nominal Voltage Property Type Number This is a property of type Number. Pages using the property "Nominal Voltage" Showing 22 pages using this property. D Distributed Generation Study/10 West 66th Street Corp + 480 + Distributed Generation Study/615 kW Waukesha Packaged System + 480 + Distributed Generation Study/Aisin Seiki G60 at Hooligans Bar and Grille + 240 + Distributed Generation Study/Arrow Linen + 480 + Distributed Generation Study/Dakota Station (Minnegasco) + 0 + Distributed Generation Study/Elgin Community College + 4,160 + Distributed Generation Study/Emerling Farm + 480 + Distributed Generation Study/Floyd Bennett + 480 + Distributed Generation Study/Harbec Plastics + 480 +

378

Direct observation of muon-pair production by high-energy muons in the liquid-argon calorimeter BARS  

Science Journals Connector (OSTI)

Experimental data accumulated over a long-term exposure of the big liquid-argon spectrometer BARS at the Institute for High Energy Physics (IHEP, Protvino) in a horizontal ... the aim of selecting events that cor...

V. B. Anikeev; S. N. Gurzhiev; S. P. Denisov; O. S. Zolina…

2005-02-01T23:59:59.000Z

379

Vehicle Technologies Office Merit Review 2014: High-Dilution Stoichiometric Gasoline Direct-Injection (SGDI) Combustion Control Development  

Broader source: Energy.gov [DOE]

Presentation given by Oak Ridge National Laboratory at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about high-dilution...

380

Cathode Synthesis and Voltage Fade: Designed Solutions Based...  

Broader source: Energy.gov (indexed) [DOE]

Cathode Synthesis and Voltage Fade: Designed Solutions Based on Theory Cathode Synthesis and Voltage Fade: Designed Solutions Based on Theory 2013 DOE Hydrogen and Fuel Cells...

Note: This page contains sample records for the topic "high voltage direct" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Addressing the Voltage Fade Issue with Lithium-Manganese-Rich...  

Broader source: Energy.gov (indexed) [DOE]

Addressing the Voltage Fade Issue with Lithium-Manganese-Rich Oxide Cathode Materials Addressing the Voltage Fade Issue with Lithium-Manganese-Rich Oxide Cathode Materials 2013 DOE...

382

A CCD Camera with Electron Decelerator for Intermediate Voltage Electron Microscopy  

SciTech Connect (OSTI)

Electron microscopists are increasingly turning to Intermediate Voltage Electron Microscopes (IVEMs) operating at 300 - 400 kV for a wide range of studies. They are also increasingly taking advantage of slow-scan charge coupled device (CCD) cameras, which have become widely used on electron microscopes. Under some conditions CCDs provide an improvement in data quality over photographic film, as well as the many advantages of direct digital readout. However, CCD performance is seriously degraded on IVEMs compared to the more conventional 100 kV microscopes. In order to increase the efficiency and quality of data recording on IVEMs, we have developed a CCD camera system in which the electrons are decelerated to below 100 kV before impacting the camera, resulting in greatly improved performance in both signal quality and resolution compared to other CCDs used in electron microscopy. These improvements will allow high-quality image and diffraction data to be collected directly with the CCD, enabling improvements in data collection for applications including high-resolution electron crystallography, single-particle reconstruction of protein structures, tomographic studies of cell ultrastructure and remote microscope operation. This approach will enable us to use even larger format CCD chips that are being developed with smaller pixels.

Downing, Kenneth H; Downing, Kenneth H.; Mooney, Paul E.

2008-03-17T23:59:59.000Z

383

Double row loop-coil configuration for high-speed electrodynamic maglev suspension, guidance, propulsion and guideway directional switching  

DOE Patents [OSTI]

A stabilization and propulsion system are disclosed comprising a series of loop-coils arranged in parallel rows wherein two rows combine to form one of two magnetic rails. Levitation and lateral stability are provided when the induced field in the magnetic rails interacts with the superconducting magnets mounted on the magnetic levitation vehicle. The loop-coils forming the magnetic rails have specified dimensions and a specified number of turns and by constructing differently these specifications, for one rail with respect to the other, the angle of tilt of the vehicle can be controlled during directional switching. Propulsion is provided by the interaction of a traveling magnetic wave associated with the coils forming the rails and the superconducting magnets on the vehicle. 12 figs.

He, J.; Rote, D.M.

1996-05-21T23:59:59.000Z

384

High-pressure late cycle direct injection of natural gas in a rail medium speed diesel engine  

SciTech Connect (OSTI)

The performance of an Electro-Motive Division (EMD) 567B, two-cylinder locomotive research engine, when operated on high-pressure/late-cycle injection of natural gas, is presented in this paper. A redesign and fabrication of the fuel system was undertaken to facilitate the consumption of natural gas. A small percentage of No.2 diesel fuel (DF-2) was used to ignite the natural gas. Engine performance, while running natural gas, resulted in matching rated speed and power with slightly lower thermal efficiency. Full power was achieved with a ratio of 99 percent natural gas and 1 percent diesel fuel. However, at high natural gas to diesel fuel ratios, audible knock was detected. The primary objective of the project was to establish technical feasibility of, and basic technology for, operating medium-speed rail diesel engines on high-pressure natural gas. Secondary objectives were to attain adequate engine performance levels for rail application, develop a system oriented toward retrofit of in-service locomotives, and realize any potential improvements in thermal efficiency due to use of the high-pressure/late-cycle approach.

Wakenell, J.F.; O'Neal, G.B.; Baker, Q.A.

1987-01-01T23:59:59.000Z

385

Direct conversion of surplus fissile materials, spent nuclear fuel, and other materials to high-level-waste glass  

SciTech Connect (OSTI)

With the end of the cold war the United States, Russia, and other countries have excess plutonium and other materials from the reductions in inventories of nuclear weapons. The United States Academy of Sciences (NAS) has recommended that these surplus fissile materials (SFMs) be processed so they are no more accessible than plutonium in spent nuclear fuel (SNF). This spent fuel standard, if adopted worldwide, would prevent rapid recovery of SFMs for the manufacture of nuclear weapons. The NAS recommended investigation of three sets of options for disposition of SFMs while meeting the spent fuel standard: (1) incorporate SFMs with highly radioactive materials and dispose of as waste, (2) partly burn the SFMs in reactors with conversion of the SFMs to SNF for disposal, and (3) dispose of the SFMs in deep boreholes. The US Government is investigating these options for SFM disposition. A new method for the disposition of SFMs is described herein: the simultaneous conversion of SFMs, SNF, and other highly radioactive materials into high-level-waste (HLW) glass. The SFMs include plutonium, neptinium, americium, and {sup 233}U. The primary SFM is plutonium. The preferred SNF is degraded SNF, which may require processing before it can be accepted by a geological repository for disposal.

Forsberg, C.W.; Elam, K.R.

1995-01-31T23:59:59.000Z

386

Novel passive lossless turn-on snubber for voltage source inverters  

SciTech Connect (OSTI)

A novel passive lossless turn-on snubber with a soft clamped turn-off snubber circuit for voltage source inverters is proposed. The energy trapped in the snubber is recovered into the dc supply and load without any active devices, associated control circuitry, or resistors. The overshoot voltage on the switches is clamped, and the peak switch current is low, making this snubber suitable for use in high-power insulated gate bipolar transistor (IGBT) inverters.

He, X.; Qian, Z.M. [Zhejiang Univ., Hangzhou (China). Dept. of Electrical Engineering; Finney, S.J.; Williams, B.W. [Heriot-Watt Univ., Edinburgh (United Kingdom). Dept. of Computing and Electrical Engineering

1997-01-01T23:59:59.000Z

387

Analysis of an extremely fast valve opening camless system to improve transient performance in a turbocharged high speed direct injection diesel engine  

Science Journals Connector (OSTI)

This article describes a theoretical study on the performance optimisation of a high speed direct injection turbocharged diesel engine equipped with an electro-hydraulic variable valve actuation 'camless' system. This system provides extremely fast valve opening and closing slopes. Thus, its potential for recovering part of the energy lost in the valves by reducing gas flow sonic conditions in the valve throat has been investigated. This study has been mainly focused on the analysis of engine performance during a load transient evolution, but the full load steady state attained at the end of the load transient has been also discussed. The results of this investigation have confirmed important improvements in engine performance during the load transient owing to less energy being lost across the valves, which directly results in more energy being available in the turbine. This benefit has also been observed at full load steady state conditions.

J. Benajes; J.R. Serrano; V. Dolz; R. Novella

2009-01-01T23:59:59.000Z

388

LM231A/LM231/LM331A/LM331 Precision Voltage-to-Frequency Converters  

E-Print Network [OSTI]

LM231A/LM231/LM331A/LM331 Precision Voltage-to-Frequency Converters General Description The LM231/LM331 family of voltage-to-frequency converters are ideally suited for use in simple low, the LM231A/LM331A attain a new high level of accuracy versus temperature which could only be at- tained

Lanterman, Aaron

389

8 - High-Performance Polyimides and Related Thermoset Polymers: Past and Present Development, and Future Research Directions  

Science Journals Connector (OSTI)

Publisher Summary Polyimides, prepared from a variety of dianhydride and diamine monomers, are characterized by repeating imide structural units (I) in the polymer backbone. This structure contributes to the exceptional thermal and oxidative stability of polyimides. It is necessary to have the imide structure along with the aromatic moieties because wholly aromatic polymers such as polyphenylenes are not as thermo-oxidatively resistant as polyimides. The combination of the aromatic structure and the imide structure results in a polymer with a high glass transition temperature (Tg) and high thermo-oxidative stability. These aromatic polyimides can be processed either as thermosetting or thermoplastic resins, depending on the processing characteristics of the polymer resin or the process required to transform the prepolymer resin into the final form or shape. These polymers are broken down conveniently into three categories, depending on their processing characteristics. One of these categories includes thermoplastic polyimides. The polyimides in this first category are processed via precursors that undergo condensation reactions to form the final product. The precursors are usually the amic acid or the amic ester intermediate. They are tractable, soluble in common organic solvents, and generally applied as lacquers.

Abraham L. Landis; Kreisler S.Y. Lau

1999-01-01T23:59:59.000Z

390

Crystalline mesoporous tungsten oxide nanoplate monoliths synthesized by directed soft template method for highly sensitive NO{sub 2} gas sensor applications  

SciTech Connect (OSTI)

Graphical abstract: Display Omitted Highlights: ? Mesoporous WO{sub 3} nanoplate monoliths were obtained by direct templating synthesis. ? Enable effective accession of the analytic molecules for the sensor applications. ? The WO{sub 3} sensor exhibited a high performance to NO{sub 2} gas at low temperature. -- Abstract: Controllable synthesis of nanostructured metal oxide semiconductors with nanocrystalline size, porous structure, and large specific surface area is one of the key issues for effective gas sensor applications. In this study, crystalline mesoporous tungsten oxide nanoplate-like monoliths with high specific surface areas were obtained through instant direct-templating synthesis for highly sensitive nitrogen dioxide (NO{sub 2}) sensor applications. The copolymer soft template was converted into a solid carbon framework by heat treatment in an inert gas prior to calcinations in air to sustain the mesoporous structure of tungsten oxide. The multidirectional mesoporous structures of tungsten oxide with small crystalline size, large specific surface area, and superior physical characteristics enabled the rapid and effective accession of analytic gas molecules. As a result, the sensor response was enhanced and the response and recovery times were reduced, in which the mesoporous tungsten oxide based gas sensor exhibited a superior response of 21,155% to 5 ppm NO{sub 2}. In addition, the developed sensor exhibited selective detection of low NO{sub 2} concentration in ammonia and ethanol at a low temperature of approximately 150 °C.

Hoa, Nguyen Duc, E-mail: ndhoa@itims.edu.vn [International Training Institute for Materials Science (ITIMS), Hanoi University of Science and Technology (HUST) (Viet Nam); Duy, Nguyen Van [International Training Institute for Materials Science (ITIMS), Hanoi University of Science and Technology (HUST) (Viet Nam)] [International Training Institute for Materials Science (ITIMS), Hanoi University of Science and Technology (HUST) (Viet Nam); Hieu, Nguyen Van, E-mail: hieu@itims.edu.vn [International Training Institute for Materials Science (ITIMS), Hanoi University of Science and Technology (HUST) (Viet Nam)

2013-02-15T23:59:59.000Z

391

An experimental–numerical investigation of heat distribution and stress field in single- and multi-track laser cladding by a high-power direct diode laser  

Science Journals Connector (OSTI)

Abstract High-power direct diode laser (HPDDL) cladding offers several advantages in the laser surface modification and repair of high-value parts. The wider beam and uniform energy distribution in the direct diode laser provide a smooth heating and cooling cycle during the cladding process. Subsequently, lower dimensional distortion and thermally-induced stress occur during the process. In this paper, temperature evolution and molten pool dimensions as well as stress-and-strain fields were studied by utilizing experimental and numerical methods. A three-dimensional (3D) transient uncoupled thermo-elastic–plastic model was developed to simulate a thermal process during the single- and multi-track laser cladding and the thermally-induced residual stress in the laser cladding. The effect of latent heat and phase transformations are considered in the thermal analysis. The numerical results were validated by experimentally-measured values, and the maximum prediction error was 3.5%. The experimental results were collected by in-situ monitoring techniques (e.g., thermocouples and a high-speed CCD camera). The level of residual stresses at the cladded surfaces were measured by an X-ray diffractometer. In addition, the effect of scanning speed on the thermal and stress evolution was quantitatively discussed.

Parisa Farahmand; Radovan Kovacevic

2014-01-01T23:59:59.000Z

392

Physical simulation study of dynamic voltage instability  

SciTech Connect (OSTI)

This paper presents a physical simulation of the dynamic behavior of voltage instability in an interconnected multimachine environment. The dynamic evolving process leading to eventual voltage collapse, the scenario of the progressive reactive support reduction resulting from the MXL protection relays, the OLTC operation, and the effect of switched-in capacitor banks are examined using physical facilities in the laboratory. The physical simulation results are also compared with digital simulation results. This physical investigation provides a reliable foundation for the effective development of assessment approaches and countermeasures.

Tso, S.K.; Zhu, T.X. [Univ. of Hong Kong (Hong Kong); Zeng, Q.Y. [Electric Power Research Inst., Beijing (China); Lo, K.L. [Univ. of Strathclyde, Glasgow (United Kingdom). Dept. of Electrical and Electrical Engineering

1995-12-31T23:59:59.000Z

393

Direct photoetching of polymers using radiation of high energy density from a table-top extreme ultraviolet plasma source  

Science Journals Connector (OSTI)

In order to perform material interaction studies with intense extreme ultraviolet(EUV)radiation a Schwarzschild mirror objective coated with Mo/Si multilayers was adapted to a compact laser-driven EUV plasma source utilizing a solid Au target. By 10× demagnified imaging of the plasma a maximum pulse energy density of ? 0.73 ? J / cm 2 at a wavelength of 13.5 nm can be achieved in the image plane of the objective at a pulse duration of 8.8 ns. In this paper we present EUV photoetching rates measured for polymethyl methacrylate polycarbonate and polytetrafluoroethylene at various fluence levels. A linear dependence between etch depth and applied EUV pulse number could be observed without the necessity for any incubation pulses. By evaluating the slope of these data etch rates were determined revealing also a linear behavior for low fluences. A threshold energy density could not be observed. The slope of the linear etch regime as well as deviations from the linear trend at higher energy densities are discussed and compared to data known from deep UV laser ablation. Furthermore the surface roughness of the structuredpolymers was measured by atomic force microscopy and compared to the nonirradiated polymer surface indicating a rather smooth etch process (roughness increase of 20%–30%). The different shapes of the etch craters observed for the three polymers at high energy densities can be explained by the measured fluence dependence of the etch rates having consequences for the proper use of polymerablation for beam profiling of focused EUVradiation.

Frank Barkusky; Armin Bayer; Christian Peth; Klaus Mann

2009-01-01T23:59:59.000Z

394

Direct photoetching of polymers using radiation of high energy density from a table-top extreme ultraviolet plasma source  

SciTech Connect (OSTI)

In order to perform material interaction studies with intense extreme ultraviolet (EUV) radiation, a Schwarzschild mirror objective coated with Mo/Si multilayers was adapted to a compact laser-driven EUV plasma source utilizing a solid Au target. By 10x demagnified imaging of the plasma a maximum pulse energy density of {approx}0.73 J/cm{sup 2} at a wavelength of 13.5 nm can be achieved in the image plane of the objective at a pulse duration of 8.8 ns. In this paper we present EUV photoetching rates measured for polymethyl methacrylate, polycarbonate, and polytetrafluoroethylene at various fluence levels. A linear dependence between etch depth and applied EUV pulse number could be observed without the necessity for any incubation pulses. By evaluating the slope of these data, etch rates were determined, revealing also a linear behavior for low fluences. A threshold energy density could not be observed. The slope of the linear etch regime as well as deviations from the linear trend at higher energy densities are discussed and compared to data known from deep UV laser ablation. Furthermore, the surface roughness of the structured polymers was measured by atomic force microscopy and compared to the nonirradiated polymer surface, indicating a rather smooth etch process (roughness increase of 20%-30%). The different shapes of the etch craters observed for the three polymers at high energy densities can be explained by the measured fluence dependence of the etch rates, having consequences for the proper use of polymer ablation for beam profiling of focused EUV radiation.

Barkusky, Frank; Bayer, Armin; Peth, Christian; Mann, Klaus [Laser-Laboratorium-Goettingen e.V., Hans-Adolf-Krebs-Weg 1, D-37077 Goettingen (Germany)

2009-01-01T23:59:59.000Z

395

A High shear stress segment along the San Andreas Fault: Inferences based on near-field stress direction and stress magnitude observations in the Carrizo Plain Area  

SciTech Connect (OSTI)

Nearly 200 new in-situ determinations of stress directions and stress magnitudes near the Carrizo plain segment of the San Andreas fault indicate a marked change in stress state occurring within 20 km of this principal transform plate boundary. A natural consequence of this stress transition is that if the observed near-field ``fault-oblique`` stress directions are representative of the fault stress state, the Mohr-Coulomb shear stresses resolved on San Andreas sub-parallel planes are substantially greater than previously inferred based on fault-normal compression. Although the directional stress data and near-hydrostatic pore pressures, which exist within 15 km of the fault, support a high shear stress environment near the fault, appealing to elevated pore pressures in the fault zone (Byerlee-Rice Model) merely enhances the likelihood of shear failure. These near-field stress observations raise important questions regarding what previous stress observations have actually been measuring. The ``fault-normal`` stress direction measured out to 70 km from the fault can be interpreted as representing a comparable depth average shear strength of the principal plate boundary. Stress measurements closer to the fault reflect a shallower depth-average representation of the fault zone shear strength. If this is true, only stress observations at fault distances comparable to the seismogenic depth will be representative of the fault zone shear strength. This is consistent with results from dislocation monitoring where there is pronounced shear stress accumulation out to 20 km of the fault as a result of aseismic slip within the lower crust loading the upper locked section. Beyond about 20 km, the shear stress resolved on San Andreas fault-parallel planes becomes negligible. 65 refs., 15 figs.

Castillo, D. A., [Department of Geology and Geophysics, University of Adelaide (Australia); Younker, L.W. [Lawrence Livermore National Lab., CA (United States)

1997-01-30T23:59:59.000Z

396

Soft Magnetic Materials in High-Frequency, High-Power Conversion Applications  

E-Print Network [OSTI]

Voltage DC (HVDC) technologies aim to improve the effi- ciency of power networks and benefit from high

McHenry, Michael E.

397

Mathematical Modeling of Liquid-Feed Direct Methanol Fuel Z. H. Wang* and C. Y. Wang*,z  

E-Print Network [OSTI]

density and high Tafel slope.1 Methanol crossover further causes lower open-circuit voltage OCV and waste

398

Distribution System Voltage Regulation by Distributed Energy Resources  

SciTech Connect (OSTI)

This paper proposes a control method to regulate voltages in 3 phase unbalanced electrical distribution systems. A constrained optimization problem to minimize voltage deviations and maximize distributed energy resource (DER) active power output is solved by harmony search algorithm. IEEE 13 Bus Distribution Test System was modified to test three different cases: a) only voltage regulator controlled system b) only DER controlled system and c) both voltage regulator and DER controlled system. The simulation results show that systems with both voltage regulators and DER control provide better voltage profile.

Ceylan, Oguzhan [ORNL; Liu, Guodong [ORNL; Xu, Yan [ORNL; Tomsovic, Kevin [University of Tennessee, Knoxville (UTK)

2014-01-01T23:59:59.000Z

399

Four Phase Switched Reluctance Motor Direct Torque Control  

Science Journals Connector (OSTI)

The three-phase switched reluctance motor direct torque control method mostly is a simple transplantation of the three-phase AC asynchronous motor direct torque control method, not suitable for arbitrary-phase switched reluctance motor. In this paper, ... Keywords: SRM, Direct torque control, Flux vector, Voltage vector, Switched rule

Wang Mianhua

2011-01-01T23:59:59.000Z

400

CORRELATIONS OF THE ARRIVAL DIRECTIONS OF ULTRA-HIGH ENERGY COSMIC RAYS WITH EXTRAGALACTIC OBJECTS AS OBSERVED BY THE TELESCOPE ARRAY EXPERIMENT  

SciTech Connect (OSTI)

We search for correlations between the positions of extragalactic objects and the arrival directions of ultra-high energy cosmic rays (UHECRs) with primary energy E ? 40 EeV as observed by the surface detector array of the Telescope Array (TA) experiment during the first 40 months of operation. We examine several public astronomical object catalogs, including the Veron-Cetty and Veron catalog of active galactic nuclei. We count the number of TA events correlated with objects in each catalog as a function of three parameters: the maximum angular separation between a TA event and an object, the minimum energy of the events, and the maximum redshift of the objects. We determine the combination of these parameters that maximizes the correlations, and we calculate the probability of having the same levels of correlations from an isotropic distribution of UHECR arrival directions. No statistically significant correlations are found when penalties for scanning over the above parameters and for searching in several catalogs are taken into account.

Abu-Zayyad, T.; Allen, M.; Anderson, R.; Barcikowski, E.; Belz, J. W.; Bergman, D. R.; Blake, S. A.; Cady, R.; Hanlon, W. [High Energy Astrophysics Institute and Department of Physics and Astronomy, University of Utah, Salt Lake City, UT (United States); Aida, R. [Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Kofu, Yamanashi (Japan); Azuma, R.; Fukuda, T. [Graduate School of Science and Engineering, Tokyo Institute of Technology, Meguro, Tokyo (Japan); Cheon, B. G.; Cho, E. J. [Department of Physics and The Research Institute of Natural Science, Hanyang University, Seongdong-gu, Seoul (Korea, Republic of); Chiba, J. [Department of Physics, Tokyo University of Science, Noda, Chiba (Japan); Chikawa, M. [Department of Physics, Kinki University, Higashi Osaka, Osaka (Japan); Cho, W. R. [Department of Physics, Yonsei University, Seodaemun-gu, Seoul (Korea, Republic of); Fujii, H. [Institute of Particle and Nuclear Studies, KEK, Tsukuba, Ibaraki (Japan); Fujii, T. [Graduate School of Science, Osaka City University, Osaka (Japan); Fukushima, M. [Institute for Cosmic Ray Research, University of Tokyo, Kashiwa, Chiba (Japan); and others

2013-11-10T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage direct" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Sacramento Area Voltage Support Environmental Impact Statement  

Broader source: Energy.gov (indexed) [DOE]

E E R R A N E V A D A R E G I O N Sacramento Area Voltage Support DRAFT ENVIRONMENTAL IMPACT STATEMENT DRAFT ENVIRONMENTAL IMPACT STATEMENT DOE/EIS-0323 NOVEMBER 2002 COVER SHEET Title: Sacramento Area Voltage Support Draft Environmental Impact Statement (EIS) Lead Agency: Western Area Power Administration (Western) Location: Alameda, Contra Costa, Placer, Sacramento, San Joaquin, and Sutter Counties, State of California. EIS Number: DOE/EIS-0323 Contact: Ms. Loreen McMahon, Environmental Project Manager Western Area Power Administration Sierra Nevada Region 114 Parkshore Drive Folsom, CA 95630 (916) 353-4460 (916) 985-1936 fax email: mcmahon@wapa.gov Website: Information is also available on our website: www.wapa.gov Hotline: 1-877-913-4440 (toll-free) Abstract The Western Area Power Administration's Central Valley Project transmission system forms an integral part of

402

Power-One produces the industry's broadest selection of linear power supplies with output voltages from 5 volts through 250 volts. Rugged  

E-Print Network [OSTI]

-A 5V @ 9A (Note 1,5) N 5V HD5-12/OVP-A 5V @ 12A (Note 1,5) D HE5-18/OVP-A 5V @ 18A (Note 1,5) E F5 regulatory standards, and is CE Marked to the Low Voltage Directive (LVD). INTERNATIONAL SERIES LINEARS marked to Low Voltage Directive · 100% Burn-In · 2 Year Warranty · Overvoltage Protection (OVP) Standard

Berns, Hans-Gerd

403

Low Voltage White Phosphorescent OLED Achievements  

Broader source: Energy.gov [DOE]

Universal Display Corporation (UDC) and its research partners at Princeton University and the University of Southern California have succeeded in developing a white phosphorescent OLED (PHOLED™) that achieved a record efficiency of 20 lumens per watt. This achievement is the result of the team's collaborative efforts to increase the efficiency of PHOLED lighting by focusing on two critical factors: lowering the drive voltages and increasing the amount of light extracted.

404

A BIST Technique for RF Voltage-Controlled Oscillators  

Science Journals Connector (OSTI)

A built-in self-test (BIST) architecture is proposed for voltage-controlled oscillators (VCO) operating at multigigahertz frequencies. By utilizing a frequency divider and a frequency-to-voltage converter (FVC), the output frequency and tuning range ...

Hsieh-Hung Hsieh; Yen-Chih Huang; Liang-Hung Lu; Guo-Wei Huang

2007-10-01T23:59:59.000Z

405

LM2907LM2917FrequencytoVoltageConverter February 1995  

E-Print Network [OSTI]

TL H 7942 LM2907LM2917FrequencytoVoltageConverter February 1995 LM2907 LM2917 Frequency to Voltage Converter General Description The LM2907 LM2917 series are monolithic frequency to voltage converters doubling for low ripple full input protection in two versions (LM2907-8 LM2917-8) and its output swings

Wedeward, Kevin

406

Low voltage vertical recording preamplifier for hard disk drives  

E-Print Network [OSTI]

. . . . . . . . . . . . . . . . . 4 2 Input drivers of the preamplifier along with the decoupling caps and parasitics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 3 Voltage bias voltage sensing scheme . . . . . . . . . . . . . . . . . . . 8 4 Current bias current... sensing scheme . . . . . . . . . . . . . . . . . . 9 5 Current bias scheme which common mode sense voltage to DE . . . . 10 6 Decoupling the inputs of the differential pair using feedback . . . . . 11 7 Barkhausen noise...

Mellachervu, Ramachandra Murthy

2004-11-15T23:59:59.000Z

407

High Voltage DC Transmission 1.0 Introduction  

E-Print Network [OSTI]

HVDC HelWin 2 Germany - Büttel 53°5501N9° 1355E Germany - HelWin Beta platform 54°2711N 7 °4420E 130 320 690 2015 IGBT HVDC DolWin 2 Germany - Heede 52°5852N7° 1526E Germany - DolWin Bets platform 53 14 450 650 2014 Thy HVDC SylWin 1 Germany - Büttel 53°5501N9° 1355E Germany - SylWin Alpha platform

McCalley, James D.

408

,"Table 6. Proposed High-voltage Transmission Line Additions...  

U.S. Energy Information Administration (EIA) Indexed Site

,2010,"US","WECC","NORW","AC","300-399","300-399",1398,6,2011,"South Jordan, UT","SLC,UT",0,"OH",,,14354,"PACE","I",100,"Camp Williams- Terminal 345 kV 1...

409

,"Table 6. Proposed High-voltage Transmission Line Additions...  

U.S. Energy Information Administration (EIA) Indexed Site

"Planned","Reliability"," " ,"US","SERC","Southeastern","AC","100-120",115,290,5,2014,"Jordan dam","Bouldin Dam",0,"OH","Unknown","Unknown",795,"Other","Single",1,1,195,"Alabama...

410

Electrolytes and Separators for High Voltage Li Ion Cells  

Broader source: Energy.gov [DOE]

2012 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting

411

Nanoscale Morphological and Chemical Changes of High Voltage...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

reconstructed from nano-tomography data (left panel). The distribution of the three transition metal ions is rendered and quantified in the middle and right columns. In this...

412

Studies on High Voltage Lithium Rich MNC Composite Cathodes  

Broader source: Energy.gov [DOE]

2012 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting

413

Optically-initiated silicon carbide high voltage switch  

DOE Patents [OSTI]

An improved photoconductive switch having a SIC or other wide band gap substrate material, such as GaAs and field-grading liners composed of preferably SiN formed on the substrate adjacent the electrode perimeters or adjacent the substrate perimeters for grading the electric fields.

Caporaso, George J. (Livermore, CA); Sampayan, Stephen E. (Manteca, CA); Sullivan, James S. (Livermore, CA); Sanders, David M. (Livermore, CA)

2012-02-28T23:59:59.000Z

414

Highline Pacific Northwests High-Voltage Transmission System  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Elliot Mainzer Greg Delwiche Claudia Andrews Mark Gendron Cathy Ehli Administrators of BPA Nancy Mitman Mission Vision Values History Vintage Film Vault 75th Anniversary...

415

Electrolytes and Separators for High Voltage Li Ion Cells  

Broader source: Energy.gov [DOE]

2011 DOE Hydrogen and Fuel Cells Program, and Vehicle Technologies Program Annual Merit Review and Peer Evaluation

416

Electrolytes and Separators for High Voltage Li Ion Cells  

Broader source: Energy.gov [DOE]

2013 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting

417

High-Voltage Solid Polymer Batteries for Electric Drive Vehicles  

Broader source: Energy.gov [DOE]

2012 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting

418

High-Voltage Solid Polymer Batteries for Electric Drive Vehicles  

Broader source: Energy.gov [DOE]

2013 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting

419

Four generations of high-voltage electron microscopes  

Science Journals Connector (OSTI)

......TM' py and Analysis, ed. Nixon , , , , , ,, , , , W C, p. 188, (Institute of Physics Conf. Series Nr. 10, London ceed only if the ballistic exchange rate exceeds the thermal a n d Bristol). rate sufficiently. This implies that the transformation......

Alfred Seeger

1999-01-01T23:59:59.000Z

420

Studies on High Voltage Lithium Rich MNC Composite Cathodes  

Broader source: Energy.gov (indexed) [DOE]

Compositions from Toda Inc. Subtask 1.2 : Improving the rate performance using 1.5 wt% carbon fiber additives ProgressStatus : 100% complete Task 2: Ex situ SoC analysis of...

Note: This page contains sample records for the topic "high voltage direct" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

High Voltage Electrolytes for Li-ion Batteries  

Broader source: Energy.gov (indexed) [DOE]

effective than HFiP in improving cycle life in LNMOgraphite cells at RT. - Synthesized Al(HFiP) additives with electron deficient center Al - Calculated oxidation potential of...

422

High Voltage Electrolytes for Li-ion Batteries  

Broader source: Energy.gov [DOE]

2013 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting

423

High-Voltage Solid Polymer Batteries for Electric Drive Vehicles  

Broader source: Energy.gov (indexed) [DOE]

complete Timeline Budget Barriers Partners Overview * Barriers addressed: - A. Battery cost - C. Performance: Energy Density - E. Lifetime * Targets - prototype cells...

424

ESS 2012 Peer Review - Low Cost, Manufacturable High Voltage...  

Broader source: Energy.gov (indexed) [DOE]

11 kV 600 kW ESS 6 Comparison of solutions for a 13.8 kV 480 V 100 kVA substation transformer 2 S. Bhattacharya, "15kV SiC IGBT Modules for Grid Scale Power Conversion",...

425

High Voltage Electrolytes for Li-ion Batteries  

Broader source: Energy.gov (indexed) [DOE]

below 4.5 V; * Sulfone-based solvents showed anodic stability up to 5.8 V but: * SEI chemistry from reduction of sulfones does not provide protection of graphitic anodes * Most...

426

Four generations of high-voltage electron microscopes  

Science Journals Connector (OSTI)

......microscopes 307 Table 3 Edge lengths of elementary cubes. a0, and separations...data were obtained by electrical resistance measurements [41,42], those...measure- ment of the residual electric resistance using 'conven- tional' accelerator......

Alfred Seeger

1999-01-01T23:59:59.000Z

427

CLNS 03/1827 VERY HIGH VOLTAGE PHOTOEMISSION ELECTRON GUNS*  

E-Print Network [OSTI]

photoemission electron guns, will be reviewed. INTRODUCTION The successful demonstration of beam energy recovery with demanding specifications on transverse and longitudinal emittances. DC electron guns with photoemission, there are few restrictions on vacuum chamber geometry or the location and size of ports, and many choices

428

High Voltage Electrolytes for Li-ion Batteries  

Broader source: Energy.gov (indexed) [DOE]

FY09 and FY10 * 400K (DOE) Timeline Budget Barriers * Argonne National Laboratory * Saft Batteries * University of Maryland Partners * State-of-the-art LiPF 6 Carbonate...

429

High Voltage Electrolytes for Li-ion Batteries  

Broader source: Energy.gov (indexed) [DOE]

* Funding for FY12 * 250K Timeline Budget Barriers * Argonne National Laboratory * Saft Batteries * U of Texas, Austin * U of Utah * U of Maryland Partners * SOA electrolytes...

430

Utility-Scale Power Router: Dynamic Control of Grid Assets Using Direct AC Converter Cells  

SciTech Connect (OSTI)

ADEPT Project: Georgia Tech is developing a cost-effective, utility-scale power router that uses an enhanced transformer to more efficiently direct power on the grid. Existing power routing technologies are too expensive for widespread use, but the ability to route grid power to match real-time demand and power outages would significantly reduce energy costs for utilities, municipalities, and consumers. Georgia Tech is adding a power converter to an existing grid transformer to better control power flows at about 1/10th the cost of existing power routing solutions. Transformers convert the high-voltage electricity that is transmitted through the grid into the low-voltage electricity that is used by homes and businesses. The added converter uses fewer steps to convert some types of power and eliminates unnecessary power storage, among other improvements. The enhanced transformer is more efficient, and it would still work even if the converter fails, ensuring grid reliability.

None

2010-09-01T23:59:59.000Z

431

Capacitively coupled RF voltage probe having optimized flux linkage  

DOE Patents [OSTI]

An RF sensor having a novel current sensing probe and a voltage sensing probe to measure voltage and current. The current sensor is disposed in a transmission line to link all of the flux generated by the flowing current in order to obtain an accurate measurement. The voltage sensor is a flat plate which operates as a capacitive plate to sense voltage on a center conductor of the transmission line, in which the measured voltage is obtained across a resistance leg of a R-C differentiator circuit formed by the characteristic impedance of a connecting transmission line and a capacitance of the plate, which is positioned proximal to the center conductor.

Moore, James A. (Powell, TN); Sparks, Dennis O. (Maryville, TN)

1999-02-02T23:59:59.000Z

432

Method of Controlling Corona Effects and Breakdown Voltage of Small Air Gaps Stressed by Impulse Voltages  

E-Print Network [OSTI]

This paper investigates the influence of a resistor on the dielectric behavior of an air gap. The resistor is connected in series with the air gap and the latter is stressed by impulse voltage. Air gap arrangements of different geometry with either the rod or the plate grounded are stressed with impulse voltages of both positive and negative polarity. The resistor is connected in series with the air gap in the return circuit connecting the gap with the impulse generator. The method followed involves the investigation of the graphs of the charging time concerning the air gaps capacitances, in connection to the value of the resistor, the geometry of the gap, the effect of grounding and the polarity effect. It is determined that the charging time of the air gap increases, as the value of the resistor increases. It is also determined that the peak voltage value of the fully charged air gap decreases as the value of the resistor increases. The results of the mathematical and simulation analysis are compared with the results of the oscillograms taken from experimental work. In addition and consequently to the above results it is concluded from the experimental work that the in series connection of the resistor in the circuit has significant influence on corona pulses (partial discharges) occurring in the gap and on the breakdown voltage of the gap. A new method of controlling the corona effects and consequently the breakdown voltage of small air gaps stressed by impulse voltage of short duration in connection to the ground effect and the polarity effect has arisen. Furthermore through mathematical analysis of the charging graphs obtained from simulation and experimental oscillograms there was a calculation of the values of the capacitance of the air gaps in relation to their geometry and the results were compared to the values calculated with mathematical analysis.

Athanasios Maglaras; Trifon Kousiouris; Frangiskos Topalis; Dimitrios Katsaros; Leandros A. Maglaras; Konstantina Giannakopoulou

2014-10-15T23:59:59.000Z

433

Transient recovery voltage considerations in the application of medium voltage circuit breakers  

SciTech Connect (OSTI)

Medium Voltage Circuit Breakers can fail to interrupt 3-phase fault currents when power systems have Transient Recovery Voltage (TRV) characteristics which exceed the rating of the circuit breaker. This paper examines the application of 13.8kV generation and load switchgear for an oil refinery in which circuit parameters as originally designed would have exceeded the 13.8kV circuit breakers TRV ratings had corrective measures not been taken. This paper illustrates this case and discusses the basis of TRV, how TRV is assessed, and alternative actions taken to bring circuits to within the 13.8 kV circuit breaker ratings.

Swindler, D.L.; Schwartz, P.; Hamer, P.S.; Lambert, S.R.

1995-12-31T23:59:59.000Z

434

Kirchhoff voltage law corrected for radiating circuits  

E-Print Network [OSTI]

When a circular loop composed by a RLC is put to oscillate, the oscillation will eventually vanish in an exponentially decaying current, even considering superconducting wires, due to the emission of electric and magnetic dipole radiation. In this work we propose a modification on the Kirchhoff voltage law by adding the radiative contributions to the energy loss as an effective resistance, whose value is relatively small when compared to typical resistance value, but fundamental to describe correctly real circuits. We have also analysed the change in the pattern of the radiation spectra emitted by the circuit as we vary both the effective and electrical resistance.

Lara, Vitor

2014-01-01T23:59:59.000Z

435

Chemical detection and laser wavelength stabilization employing spectroscopic absorption via laser compliance voltage sensing  

DOE Patents [OSTI]

Systems and methods are disclosed that provide a direct indication of the presence and concentration of an analyte within the external cavity of a laser device that employ the compliance voltage across the laser device. The systems can provide stabilization of the laser wavelength. The systems and methods can obviate the need for an external optical detector, an external gas cell, or other sensing region and reduce the complexity and size of the sensing configuration.

Taubman, Matthew S; Phillips, Mark C

2014-03-18T23:59:59.000Z

436

Directives Help  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

All DOE directives are available through this site. While it may seem overwhelming, given the number of documents, we have provided a number of ways in which you may get to the information you need.

437

Coordination of Voltage and Frequency Feedback in Load-Frequency Control Capability of Wind Turbine  

E-Print Network [OSTI]

Coordination of Voltage and Frequency Feedback in Load-Frequency Control Capability of Wind Turbine-Frequency Control (LFC) is gradually shifted to Variable Speed Wind Turbines (VSWTs). In order to equip VSWT@et.aau.dk Abstract--In near future, with high penetration of Wind Energy (WE) in power system, the burden of Load

Silva, Filipe Faria Da

438

Experimental investigation of the effect of combined hydrogen and diesel combustion on the particulate size distribution from a high speed direct injection diesel engine  

Science Journals Connector (OSTI)

The effects of hydrogen addition and exhaust gas recirculation (EGR) levels on the exhaust particulate matter size distribution in a diesel engine have been investigated. The experiments were performed on a 2.0 litre, 4-cylinder, direct injection engine equipped with a modern high-pressure common rail. A nano-Micro-Orifice Uniform Deposit Impactor (nano-MOUDI) was used in this work to study the particulate matter size distribution. All tests were conducted at the set operating point of 1,500 rpm. The experimental work showed that the particulate matter size distribution was not dramatically altered by the addition of EGR, but the main peak was shifted towards the nucleation mode with the addition of hydrogen. The addition of hydrogen increases the emissions of nitrogen oxides (NOx), but reduces the emissions of unburnt hydrocarbons (THC). Conversely, the addition of EGR reduces NOx, but can increase THC. Hydrogen addition increases the peak cylinder pressure and the maximum rate of pressure rise.

L. McWilliam; A. Megaritis

2009-01-01T23:59:59.000Z

439

Experimental research on the feature of Talbot-Lau interferometer vs. tube accelerating voltage  

E-Print Network [OSTI]

Talbot-Lau interferometer has been used most widely to perform X-ray phase-contrast imaging with a conventional low-brilliance X-ray source, it yields high-sensitivity phase and dark-field images of sample producing low absorption contrast, thus bearing tremendous potential for future clinical diagnosis. In this manuscript, while changing accelerating voltage of the X-ray tube from 35KV to 45KV, X-ray phase-contrast imaging of a test sample were performed at each integer KV position to investigate the characteristic of a Talbot-Lau interferometer (located in the Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Japan.) vs. tube voltage. Experimental results and data analysis show that this Talbot-Lau interferometer is insensitive to the tube accelerating voltage within a certain range, fringe visibility around 44% is maintained in the aforementioned tube voltage range. This experimental research is of guiding significance for choosing optimal tube accelerating voltage with thi...

Wang, Shenghao; Wang, Zhili; Gao, Kun; Zhang, Kai; Momose, Atsushi; Wu, Ziyu

2014-01-01T23:59:59.000Z

440

High  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

the pitch of B (r), and B(r), flips toroidally, such that the unidirectional toroidal electric field drives current in opposite directions, with respect to B, in the regions...

Note: This page contains sample records for the topic "high voltage direct" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

2.3-MW Medium-Voltage, Three-Level Wind Energy Inverter Applying a Unique Bus Structure and 4.5-kV Si/SiC Hybrid Isolated Power Modules: Preprint  

SciTech Connect (OSTI)

A high-efficiency, 2.3-MW, medium-voltage, three-level inverter utilizing 4.5-kV Si/SiC (silicon carbide) hybrid modules for wind energy applications is discussed. The inverter addresses recent trends in siting the inverter within the base of multimegawatt turbine towers. A simplified split, three-layer laminated bus structure that maintains low parasitic inductances is introduced along with a low-voltage, high-current test method for determining these inductances. Feed-thru bushings, edge fill methods, and other design features of the laminated bus structure provide voltage isolation that is consistent with the 10.4-kV module isolation levels. Inverter efficiency improvement is a result of the (essential) elimination of the reverse recovery charge present in 4.5-kV Si PIN diodes, which can produce a significant reduction in diode turn-off losses as well as insulated-gate bipolar transistor (IGBT) turn-on losses. The hybrid modules are supplied in industry-standard 140 mm x 130 mm and 190 mm x 130 mm packages to demonstrate direct module substitution into existing inverter designs. A focus on laminated bus/capacitor-bank/module subassembly level switching performance is presented.

Erdman, W.; Keller, J.; Grider, D.; VanBrunt, E.

2014-11-01T23:59:59.000Z

442

Rotor current transient analysis of DFIG-based wind turbines during symmetrical voltage faults  

Science Journals Connector (OSTI)

Abstract The impact of grid voltage fault on doubly fed induction generators (DFIGs), especially rotor currents, has received much attention. So, in this paper, the rotor currents of based-DFIG wind turbines are considered in a generalized way, which can be widely used to analyze the cases under different levels of voltage symmetrical faults. A direct method based on space vector is proposed to obtain an accurate expression of rotor currents as a function of time for symmetrical voltage faults in the power system. The presented theoretical analysis is simple and easy to understand and especially highlights the accuracy of the expression. Finally, the comparable simulations evaluate this analysis and show that the expression of the rotor currents is sufficient to calculate the maximum fault current, DC and AC components, and especially helps to understand the causes of the problem and as a result, contributes to adapt reasonable approaches to enhance the fault ride through (FRT) capability of DFIG wind turbines during a voltage fault.

Yu Ling; Xu Cai; Ningbo Wang

2013-01-01T23:59:59.000Z

443

A high performance differential amplifier through the direct monolithic integration of InP HBTs and Si CMOS on silicon substrates  

E-Print Network [OSTI]

We present results on the direct monolithic integration of III-V devices and Si CMOS on a silicon substrate. InP HBTs (0.5 times 5 um2 emitter) with ft and fmax > 200 GHz were grown directly in windows adjacent to CMOS ...

Bulsara, Mayank

444

Directions and Maps  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Directions & Maps Directions & Maps Plan Your Visit Visit About the Museum Museum Hours Directions & Maps When to Visit Arrange for a Visit Around Los Alamos Contact Us invisible utility element Directions and Maps Aerial View of Los Alamos Aerial approach to the Los Alamos airport Where we're located Los Alamos (elevation 7,355 feet) is perched high atop the Pajarito Plateau in the Jemez Mountains, 35 miles northwest of Santa Fe. The Bradbury Science Museum is located in downtown Los Alamos at the corner of Central Avenue and 15th Street. If you're driving here and using GPS navigation, our address is 1350 Central Avenue, Los Alamos, NM 87544. How to get here From Albuquerque take I-25 north to Santa Fe (take NM 599 for most direct route), then US 84/285 north to Pojoaque. At Pojoaque take the NM 502 exit

445

Low voltage ride-through capability improvement of DFIG-based wind turbines under unbalanced voltage dips  

Science Journals Connector (OSTI)

Abstract This paper proposes a competent and effective scheme to enhance the ride-through capability of DFIG-based wind turbines under unbalanced voltage dip conditions. The proposed method is realized through joint use of the rotor-side converter control and a three-phase stator damping resistor (SDR) placed in series with the stator windings. By means of an asymmetrical SDR idea, during the unbalanced voltage dip the SDR resistors are activated only in phase(s) experiencing low voltage. Then, the rotor current is controlled such that no unbalance voltage appears on the stator voltage. The proposed ride-through approach limits the peak values of the rotor inrush current, electromagnetic torque and DFIG transient response at the times of occurrence and clearing the fault. It also suppresses fluctuation of the electromagnetic torque and DFIG transient response appeared during unbalanced voltage dips due to negative sequence component.

Mohsen Rahimi; Mostafa Parniani

2014-01-01T23:59:59.000Z

446

An algorithm for faulted phase and feeder selection under high impedance fault conditions  

E-Print Network [OSTI]

substation. One-line diagram of a distribution system with two feeders. Typical high impedance fault, showing little or no change in phase voltage due to the fault. . Phase voltage and high frequency current component during a staged high impedance... substation. One-line diagram of a distribution system with two feeders. Typical high impedance fault, showing little or no change in phase voltage due to the fault. . Phase voltage and high frequency current component during a staged high impedance...

Benner, Carl Lee

2012-06-07T23:59:59.000Z

447

Calmodulin and calcium differentially regulate the neuronal Nav1.1 voltage-dependent sodium channel  

SciTech Connect (OSTI)

Highlights: {yields} Both Ca{sup ++}-Calmodulin (CaM) and Ca{sup ++}-free CaM bind to the C-terminal region of Nav1.1. {yields} Ca{sup ++} and CaM have both opposite and convergent effects on I{sub Nav1.1}. {yields} Ca{sup ++}-CaM modulates I{sub Nav1.1} amplitude. {yields} CaM hyperpolarizes the voltage-dependence of activation, and increases the inactivation rate. {yields} Ca{sup ++} alone antagonizes CaM for both effects, and depolarizes the voltage-dependence of inactivation. -- Abstract: Mutations in the neuronal Nav1.1 voltage-gated sodium channel are responsible for mild to severe epileptic syndromes. The ubiquitous calcium sensor calmodulin (CaM) bound to rat brain Nav1.1 and to the human Nav1.1 channel expressed by a stably transfected HEK-293 cell line. The C-terminal region of the channel, as a fusion protein or in the yeast two-hybrid system, interacted with CaM via a consensus C-terminal motif, the IQ domain. Patch clamp experiments on HEK1.1 cells showed that CaM overexpression increased peak current in a calcium-dependent way. CaM had no effect on the voltage-dependence of fast inactivation, and accelerated the inactivation kinetics. Elevating Ca{sup ++} depolarized the voltage-dependence of fast inactivation and slowed down the fast inactivation kinetics, and for high concentrations this effect competed with the acceleration induced by CaM alone. Similarly, the depolarizing action of calcium antagonized the hyperpolarizing shift of the voltage-dependence of activation due to CaM overexpression. Fluorescence spectroscopy measurements suggested that Ca{sup ++} could bind the Nav1.1 C-terminal region with micromolar affinity.

Gaudioso, Christelle; Carlier, Edmond; Youssouf, Fahamoe [INSERM U641, Institut Jean Roche, Marseille F-13344 (France) [INSERM U641, Institut Jean Roche, Marseille F-13344 (France); Universite de la Mediterranee, Faculte de Medecine Secteur Nord, IFR 11, Marseille F-13344 (France); Clare, Jeffrey J. [Eaton Pharma Consulting, Eaton Socon, Cambridgeshire PE19 8EF (United Kingdom)] [Eaton Pharma Consulting, Eaton Socon, Cambridgeshire PE19 8EF (United Kingdom); Debanne, Dominique [INSERM U641, Institut Jean Roche, Marseille F-13344 (France) [INSERM U641, Institut Jean Roche, Marseille F-13344 (France); Universite de la Mediterranee, Faculte de Medecine Secteur Nord, IFR 11, Marseille F-13344 (France); Alcaraz, Gisele, E-mail: gisele.alcaraz@univmed.fr [INSERM U641, Institut Jean Roche, Marseille F-13344 (France) [INSERM U641, Institut Jean Roche, Marseille F-13344 (France); Universite de la Mediterranee, Faculte de Medecine Secteur Nord, IFR 11, Marseille F-13344 (France)

2011-07-29T23:59:59.000Z

448

High Performance Mixed Signal Circuits Enabled by the Direct Monolithic Heterogeneous Integration of InP HBT and Si CMOS on a Silicon Substrate  

E-Print Network [OSTI]

We present recent results on the direct heterogeneous integration of InP HBTs and Si CMOS on a silicon template wafer or SOLES (Silicon On Lattice Engineered Substrate). InP HBTs whose performance are comparable to HBTs ...

Kazior, T. E.

449

Azimuthal correlations between charged hadrons and direct photons at high-p$_{t}$ in $p+p$ and $Au+Au$ collisions at $\\sqrt{s_{NN}}$ = 200 GeV  

E-Print Network [OSTI]

Recent results at STAR for direct $\\gamma$-charged hadron azimuthal correlations in heavy-ion collisions are presented. These correlations are used to study the color charge density of the medium through the medium-induced modification of high-p$_T$ parton fragmentation. Azimuthal correlations of direct photons at high transverse energy 8 $<$ E$_T$ $<$ 16 GeV with away-side charged hadrons of transverse momentum 3 $<$ p$_T$ $<$ 6 GeV/c have been measured over a broad range of centrality for $Au+Au$ collisions and $p+p$ collisions at $\\sqrt{s_{NN}}$ = 200 GeV in the STAR experiment. The per-trigger away-side yield of direct $\\gamma$ is smaller than from $\\pi^{0}$ triggers in the same centrality class.

A. M. Hamed

2008-11-11T23:59:59.000Z

450

Simplified VO M&V Protocol Simplified Voltage Optimization (VO)  

E-Print Network [OSTI]

Simplified VO M&V Protocol 1 Simplified Voltage Optimization (VO) Measurement and Verification Protocol 1.0 Introduction 1.1 Purpose The Simplified Voltage Optimization (VO) Measurement and Verification requirements, and measurement and verification formulations are included as part of this Protocol. 1

451

Task Scheduling and Voltage Selection for Energy Minimization  

E-Print Network [OSTI]

system con gurations. 1. INTRODUCTION Energy consumption has become a primary concern in today's ICTask Scheduling and Voltage Selection for Energy Minimization Yumin Zhang Synopsys, Inc. 700 East-phase framework that inte- grates task assignment, ordering and voltage selection VS together to minimize energy

Hu, Xiaobo Sharon

452

IMPACT OF DYNAMIC VOLTAGE SCALING (DVS) ON CIRCUIT OPTIMIZATION  

E-Print Network [OSTI]

and dynamic power, respectively. Both gate sizing and Dual-VT are design-time techniques, which are applied to the circuit at a fixed voltage. On the other hand, DVS is a run-time technique and implies that the circuit will be operating at a different voltage...

Esquit Hernandez, Carlos A.

2010-01-16T23:59:59.000Z

453

LOW VOLTAGE ANALOG CIRCUITS USING STANDARD CMOS TECHNOLOGY  

E-Print Network [OSTI]

LOW VOLTAGE ANALOG CIRCUITS USING STANDARD CMOS TECHNOLOGY Phillip E. Allen, Benjamin J. Blalock, and Gabriel A. Rincon School of Electrical and Computer Engineering Georgia Institute of Technology Atlanta supply voltages in CMOS integrated circuits. As the channel lengths of CMOS technology decrease

Rincon-Mora, Gabriel A.

454

Nonlinear voltages in multiple-lead coherent conductors  

Science Journals Connector (OSTI)

We use the generalized S-matrix approach to study multiple-lead coherent conductors in the case of finite applied voltages. In this framework we discuss the transverse voltage arising in a four-lead conductor with two symmetric biased leads.

Gordey B. Lesovik and Carlo Presilla

1993-01-15T23:59:59.000Z

455

Advanced High-Speed Framing Camera Development for Fast, Visible Imaging Experiments  

SciTech Connect (OSTI)

The advances in high-voltage switching developed in this project allow a camera user to rapidly vary the number of output frames from 1 to 25. A high-voltage, variable-amplitude pulse train shifts the deflection location to the new frame location during the interlude between frames, making multiple frame counts and locations possible. The final deflection circuit deflects to five different frame positions per axis, including the center position, making for a total of 25 frames. To create the preset voltages, electronically adjustable {+-}500 V power supplies were chosen. Digital-to-analog converters provide digital control of the supplies. The power supplies are clamped to {+-}400 V so as not to exceed the voltage ratings of the transistors. A field-programmable gated array (FPGA) receives the trigger signal and calculates the combination of plate voltages for each frame. The interframe time and number of frames are specified by the user, but are limited by the camera electronics. The variable-frame circuit shifts the plate voltages of the first frame to those of the second frame during the user-specified interframe time. Designed around an electrostatic image tube, a framing camera images the light present during each frame (at the photocathode) onto the tube’s phosphor. The phosphor persistence allows the camera to display multiple frames on the phosphor at one time. During this persistence, a CCD camera is triggered and the analog image is collected digitally. The tube functions by converting photons to electrons at the negatively charged photocathode. The electrons move quickly toward the more positive charge of the phosphor. Two sets of deflection plates skew the electron’s path in horizontal and vertical (x axis and y axis, respectively) directions. Hence, each frame’s electrons bombard the phosphor surface at a controlled location defined by the voltages on the deflection plates. To prevent the phosphor from being exposed between frames, the image tube is gated off between exposures.

Amy Lewis, Stuart Baker, Brian Cox, Abel Diaz, David Glass, Matthew Martin

2011-05-11T23:59:59.000Z

456

Spark-safe low-voltage detonator  

DOE Patents [OSTI]

A column of explosive in a low-voltage detonator which makes it spark-safe ncludes an organic secondary explosive charge of HMX in the form of a thin pad disposed in a bore of a housing of the detonator in an ignition region of the explosive column and adjacent to an electrical ignition device at one end of the bore. The pad of secondary charge has an axial thickness within the range of twenty to thirty percent of its diameter. The explosive column also includes a first explosive charge of CP disposed in the housing bore in the ignition region of the explosive column next to the secondary charge pad on a side opposite from the ignition device. The first CP charge is loaded under sufficient pressure, 25 to 40 kpsi, to provide mechanical confinement of the pad of secondary charge and physical coupling thereof with the ignition device. The explosive column further includes a second explosive charge of CP disposed in the housing bore in a transition region of the explosive column next to the first CP charge on a side opposite from the pad of secondary charge. The second CP charge is loaded under sufficient pressure, about 10 kpsi, to allow occurrence of DDT. The first explosive CP charge has an axial thickness within the range of twenty to thirty percent of its diameter, whereas the second explosive CP charge contains a series of increments (nominally 4) each of which has an axial thickness-to-diameter ratio of one to two.

Lieberman, Morton L. (Albuquerque, NM)

1989-01-01T23:59:59.000Z

457

Definition: Automated Voltage And Var Control | Open Energy Information  

Open Energy Info (EERE)

Voltage And Var Control Voltage And Var Control Jump to: navigation, search Dictionary.png Automated Voltage And Var Control Automated voltage and VAR control requires coordinated operation of reactive power resources such as capacitor banks, voltage regulators, transformer load-tap changers, and distributed generation (DG) with sensors, controls, and communications systems. These devices could operate autonomously in response to local events or in response to signals from a central control system.[1] View on Wikipedia Wikipedia Definition Also Known As Volt-VAR Control (VVC) Related Terms smart grid, Reactive Power References ↑ SmartGrid.gov 'Description of Functions' An i LikeLike UnlikeLike You like this.Sign Up to see what your friends like. nline Glossary Definition Retrieved from

458

Direct costing  

E-Print Network [OSTI]

oau 5e reduced. Under the same oonOitions, even ~Me on a bread scale entails not mere1y the conduct of the direct oyeraticns cf yrccessing the materials into finished products, but also the performance of auxiliary functions. these may 'ba power y... purposes have been advanced as folkway le Most of a o03RyaxO' 8 products Grc usual13r sold at prices which oovex' full product costs y plus 861ling a%el administrative expenses, plus normal profit. The inventoi~ valuate. on should be consistent...

Browning, Donald Bullock

2012-06-07T23:59:59.000Z

459

Mitigating Voltage Fade in Cathode Materials by Improving the Atomic Level Uniformity of Elemental Distribution  

SciTech Connect (OSTI)

Li-rich and Mn-rich (LMR) layered structured materials are very promising cathodes for high-energy lithium-ion batteries. However, their fundamental structure and voltage fading mechanisms are far from being well understood. Here we report the first evidence on the reduced voltage and energy fade of LMR cathode by improving the atomic level spatial distribution of the chemical species. LMR cathode (Li[Li0.2Ni0.2M0.6]O2) prepared by co-precipitation and sol-gel methods are dominated by R-3m phase and show significant Ni-segregation at the surface of the particles. They exhibit large voltage-fade and fast capacity degradation. In contrast, LMR cathode prepared by hydrothermal assisted method is dominated by C2/m phase and minimal Ni-segregation. It also demonstrates much smaller voltage-fade and excellent capacity retention. The fundamental correlation between the atomic level spatial distribution of the chemical species and the functional stability of the materials found in this work also guide the design of other functional materials with enhanced stabilities.

Zheng, Jianming; Gu, Meng; Genc, Arda; Xiao, Jie; Xu, Pinghong; Chen, Xilin; Zhu, Zihua; Zhao, Wenbo; Pullan, Lee; Wang, Chong M.; Zhang, Jiguang

2014-04-07T23:59:59.000Z

460

Improving waveform quality in direct power control of DFIG using fuzzy controller  

Science Journals Connector (OSTI)

This paper proposes a new direct power control (DPC) strategy of double-fed induction generator using fuzzy logic controller. The active and reactive power equations are expanded, and effects of voltage vecto...

H. Z. Boroujeni; M. F. Othman; A. H. Shirdel…

2014-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage direct" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Direct numerical simulation of electroconvective instability and hysteretic current-voltage response of a permselective membrane  

E-Print Network [OSTI]

We present a systematic, multiscale, fully detailed numerical modeling for dynamics of fluid flow and ion transport covering Ohmic, limiting, and overlimiting current regimes in conductance of ion-selective membrane. By ...

Pham, Van Sang

462

Vacuum ultra-violet emission of plasma discharges with high Xe partial pressure using a cathode protective layer with high secondary electron emission  

SciTech Connect (OSTI)

In this work, the mechanism of the vacuum ultra-violet (VUV) emission of plasma discharges, with high Xe partial pressure and high ion-induced secondary electrons emission protective layer, is studied by measuring the VUV light emission directly and comparing it with two-dimensional simulations. From the panel measurement, we find that the high intensity of excimer VUV mainly contributes to the high luminous efficacy of SrCaO-plasma display panels (PDP) at a low sustain voltage. The unchanged Xe excitation efficiency indicates that the electron temperature is not decreased by the high secondary electrons emission protective layer, even though the sustain voltage is much lower. From the two-dimensional simulations, we can find that the ratio of excimer VUV to resonant VUV, which is determined by the collision rate in the discharge, is only significantly affected by the Xe partial pressure, while it is independent of the sustain voltage and the secondary-electrons-emission capability of protective layer. The unchanged average electron energy at the moment when the electric field becomes maximum confirms that the improvement of the VUV production efficiency mainly is attributed to the increase in electron heating efficiency of a PDP with high ion-induced secondary electrons emission protective layer. Combining the experimental and the simulation results, we conclude about the mechanism by which the VUV production is improved for the plasma display panel with a high Xe partial pressure and a cold cathode with high ion-induced secondary electrons emission.

Zhu, Di [School of Electronics and Information Engineering, Tianjin Polytechnic University, Tianjin (China); Song, Le, E-mail: songle@tju.edu.cn [State Key Laboratory of Precision Measuring Technology and Instruments, Tianjin University, Tianjin (China); Zhang, Xiong [School of Electronic Science and Engineering, Southeast University, Nanjing (China); Kajiyama, Hiroshi [Graduate School of Advanced Science of Matter, Hiroshima University, Higashi-hiroshima, Hiroshima (Japan)

2014-02-14T23:59:59.000Z

463

Panel Session: Optimization Techniques in Voltage Collapse Analysis," IEEE PES Summer Meeting, San Diego, July 14, 1998. Applications of Optimization to Voltage Collapse Analysis  

E-Print Network [OSTI]

Panel Session: Optimization Techniques in Voltage Collapse Analysis," IEEE PES Summer Meeting, San Diego, July 14, 1998. Applications of Optimization to Voltage Collapse Analysis Claudio A. Ca|Thispaper describesseveralapplica- tions of optimization for voltage stability analysis VSA of power systems. Voltage stability prob

Cañizares, Claudio A.

464

Direct power control of grid connected PV systems with three level NPC inverter  

SciTech Connect (OSTI)

This paper presents the control of a three-level Neutral Point Clamped (NPC) voltage source inverter for grid connected photovoltaic (PV) systems. The control method used is the Extended Direct Power Control (EDPC), which is a generic approach for Direct Power Control (DPC) of multilevel inverters based on geometrical considerations. Maximum Power Point Tracking (MPPT) algorithms, that allow maximal power conversion into the grid, have been included. These methods are capable of extracting maximum power from each of the independent PV arrays connected to each DC link voltage level. The first one is a conventional MPPT which outputs DC link voltage references to EDPC. The second one is based on DPC concept. This new MPPT outputs power increment references to EDPC, thus avoiding the use of a DC link voltage regulator. The whole control system has been tested on a three-level NPC voltage source inverter connected to the grid and results confirm the validity of the method. (author)

Alonso-Martinez, Jaime; Eloy-Garcia, Joaquin; Arnaltes, Santiago [Dept. of Electrical Engineering, University Carlos III of Madrid, Avda. Universidad 30, 28911 Leganes, Madrid (Spain)

2010-07-15T23:59:59.000Z

465

Dynamic voltage scaling of OLED displays  

Science Journals Connector (OSTI)

Unlike liquid crystal display (LCD) panels that require high-intensity backlight, organic LED (OLED) display panels naturally consume low power and provide high image quality thanks to their self-illuminating characteristic. In spite of this fact, the ... Keywords: DVS, OLED, image processing, low-power design

Donghwa Shin; Younghyun Kim; Naehyuck Chang; Massoud Pedram

2011-06-01T23:59:59.000Z

466

high  

Gasoline and Diesel Fuel Update (EIA)

0 0 Summary Our short-term outlook for a wide array of energy prices has been adjusted upward as international and domestic energy supply conditions have tightened. We think that crude oil prices are as likely as not to end the year $2 to $3 per barrel higher than our previous projections. Thus, we think that the probability of West Texas Intermediate costing an average of $30 per barrel or more at midwinter is about 50 percent. On their current track, heating oil prices are likely to be about 30 percent above year-ago levels in the fourth quarter. Prices for Q1 2001 seem more likely now to match or exceed the high level seen in Q1 2000. Tight oil markets this year and an inherent propensity for high gas utilization in incremental power supply have resulted in rising North American natural gas

467

Eliminate Excessive In-Plant Distribution System Voltage Drops...  

Broader source: Energy.gov (indexed) [DOE]

connections-can account for less than 1% to more than 4% of total plant electrical energy consumption. This two-page tip sheet recommends conducting a voltage drop survey and...

468

Long term voltage stability analysis for small disturbances  

E-Print Network [OSTI]

This dissertation attempts to establish an analytical and comprehensive framework to deal with two critical challenges associated with voltage stability analysis: 1. To study the new competitive environment appropriately and give more incentive...

Men, Kun

2009-05-15T23:59:59.000Z

469

Voltage asymmetry at the buses of a combined substation  

Science Journals Connector (OSTI)

The voltage asymmetry at the buses of a combined (ac/dc) substation is calculated by phase method, using Mathcad ... , power may be supplied to a combined substation along a common line from a limited-...

A. G. Pakulin; V. A. Zagorskii; V. F. Put’ko

2013-07-01T23:59:59.000Z

470

Operation of buck regulator with ultra-low input voltage  

E-Print Network [OSTI]

Based on the LTC3621 and LTC3624, the designed buck regulator proposed in this thesis aims to lower the allowed input voltage and increase efficiency compared to the original part without making significant changes to ...

Harris, Cory Angelo

2014-01-01T23:59:59.000Z

471

Reactive Support and Voltage Control Service: Key Issues and Challenges  

E-Print Network [OSTI]

Reactive Support and Voltage Control Service: Key Issues and Challenges George Gross^, Paolo of Illinois at Urbana-Champaign, Urbana, IL 61801, USA, e-mail gross@uiuc.edu ° Dipartimento di Ingegneria

Gross, George

472

Modeling the operating voltage of liquid metal battery cells  

E-Print Network [OSTI]

A one-dimensional, integrative model of the voltage during liquid metal battery operation has been developed to enhance the understanding of performance at the cell level. Two liquid metal batteries were studied: Mg-Sb for ...

Newhouse, Jocelyn Marie

2014-01-01T23:59:59.000Z

473

Voltage Fade, an ABR Deep Dive Project: Status and Outcomes  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Budget * Voltage Fade project * 3,900K Barriers * Calendarcycle life of lithium-ion cells being developed for PHEV and EV batteries that meet or exceed DOEUSABC goals Partners...

474

LM111/LM211/LM311 Voltage Comparator  

E-Print Network [OSTI]

LM111/LM211/LM311 Voltage Comparator 1.0 General Description The LM111, LM211 and LM311 are voltage comparators that have input currents nearly a thousand times lower than devices like the LM106 or LM710A. Both the inputs and the outputs of the LM111, LM211 or the LM311 can be isolated from system ground

Lanterman, Aaron

475

Sinusoidal voltage controlled oscillators using operational transconductance amplifiers  

E-Print Network [OSTI]

SINUSOIDAI. VOLTAGE CONTROLLED OSCILLATORS I. SING OPERATIONAL TRANSCONDUCTANCE AMPLIFIERS A Thesis JAVIFB . IOAQUIN HOYI. K I'ASSANO Suhndtted to the Graduate College ol' 'I'exes A8cM University in partial fulfillment of the requirement... for the degree of MASTER OF SCIENCE May 1985 Major Subject: Electrical Engineering SINUSOIDAL VOLTAGE CONTROLLED OSCILLATORS USING OPERATIONAI, TRANSCONDUCTANCE AMPLIFIERS A Thesis by JAVIER JOAQUIN HOYLE PASSANO Approved as to style and content by: o...

Hoyle Passano, Javier Joaquin

1985-01-01T23:59:59.000Z

476

Image-line voltage controlled oscillators and grating antennas  

E-Print Network [OSTI]

IMAGE-LINE VOLTAGE CONTROLLED OSCILLATORS AND GRATING ANTENNAS A Thesis by ALEXANDER MacDONALD KIRK Submitted to the Office of Graduate Studies of Texas ABM University in partial fulfillment of the requirements for the degree of MASTER... OF SCIENCE May 1991 Major Subject: Electrical Engineering IMAGE-LINE VOLTAGE CONTROLLED OSCILLATORS AND GRATING ANTENNAS A Thesis by ALEXANDER MacDONALD KIRK Approved as to style and content by: Kai Chang (Chair of Committee) Robert D. Nevels...

Kirk, Alexander MacDonald

1991-01-01T23:59:59.000Z

477

High-Temperature Co-electrolysis of Steam and Carbon Dioxide for Direct Production of Syngas; Equilibrium Model and Single-Cell Tests  

SciTech Connect (OSTI)

An experimental study has been completed to assess the performance of single solid-oxide electrolysis cells operating over a temperature range of 800 to 850ºC in the coelectrolysis mode, simultaneously electrolyzing steam and carbon dioxide for the direct production of syngas. The experiments were performed over a range of inlet flow rates of steam, carbon dioxide, hydrogen and nitrogen and over a range of current densities (-0.1 to 0.25 A/cm2) using single electrolyte-supported button electrolysis cells. Steam and carbon dioxide consumption rates associated with electrolysis were measured directly using inlet and outlet dewpoint instrumentation and a gas chromatograph, respectively. Cell operating potentials and cell current were varied using a programmable power supply. Measured values of open-cell potential and outlet gas composition are compared to predictions obtained from a chemical equilibrium coelectrolysis model. Model predictions of outlet gas composition based on an effective equilibrium temperature are shown to agree well with measurements. Cell area-specific resistance values were similar for steam electrolysis and coelectrolysis.

O'Brien, J. E.; Stoots, C. M.; Herring, J. S.; Hartvigsen, J. J.

2007-07-01T23:59:59.000Z

478

Centralized wind power plant voltage control with optimal power flow algorithm.  

E-Print Network [OSTI]

??This thesis presents a method of controlling the reactive power injected into a medium-voltage collection system by multiple wind turbine generators such that the voltage… (more)

Kline, Jared Andrew

2011-01-01T23:59:59.000Z

479

Integrated, Low Voltage, DynamicallyIntegrated, Low Voltage, Dynamically Adaptive BuckAdaptive Buck--Boost ConverterBoost Converter  

E-Print Network [OSTI]

Improvement in battery life Low voltage Single cell operation (Li-ion/NiCd/NiMH/Fuel Cell) Integrated Linearity degradation #12;55Georgia Tech Analog Consortium Biranchinath Sahu School of Electrical

Rincon-Mora, Gabriel A.

480

Performance assessment of the direct disposal in unsaturated tuff or spent nuclear fuel and high-level waste owned by USDOE: Volume 2, Methodology and results  

SciTech Connect (OSTI)

This assessment studied the performance of high-level radioactive waste and spent nuclear fuel in a hypothetical repository in unsaturated tuff. The results of this 10-month study are intended to help guide the Office of Environment Management of the US Department of Energy (DOE) on how to prepare its wastes for eventual permanent disposal. The waste forms comprised spent fuel and high-level waste currently stored at the Idaho National Engineering Laboratory (INEL) and the Hanford reservations. About 700 metric tons heavy metal (MTHM) of the waste under study is stored at INEL, including graphite spent nuclear fuel, highly enriched uranium spent fuel, low enriched uranium spent fuel, and calcined high-level waste. About 2100 MTHM of weapons production fuel, currently stored on the Hanford reservation, was also included. The behavior of the waste was analyzed by waste form and also as a group of waste forms in the hypothetical tuff repository. When the waste forms were studied together, the repository was assumed also to contain about 9200 MTHM high-level waste in borosilicate glass from three DOE sites. The addition of the borosilicate glass, which has already been proposed as a final waste form, brought the total to about 12,000 MTHM.

Rechard, R.P. [ed.

1995-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage direct" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

An amorphous alloy core medium frequency magnetic-link for medium voltage photovoltaic inverters  

Science Journals Connector (OSTI)

The advanced magnetic materials with high saturation flux density and low specific core loss have led to the development of an efficient compact and lightweight multiple-input multiple-output medium frequency magnetic-link. It offers a new route to eliminate some critical limitations of recently proposed medium voltage photovoltaic inverters. In this paper a medium frequency magnetic-link is developed with Metglas amorphous alloy 2605S3A. The common magnetic-link generates isolated and balanced multiple DC supplies for all of the H-bridge inverter cells of the medium voltage inverter. The design and implementation of the prototype test platform and the experimental test results are analyzed and discussed. The medium frequency non-sinusoidal excitation electromagnetic characteristics of alloy 2605S3A are also compared with that of alloy 2605SA1. It is expected that the proposed new technology will have great potential for future renewable power generation systems and smart grid applications.

2014-01-01T23:59:59.000Z

482

Capability constraints to mitigate voltage fluctuations from DFIG wind farms when delivering ancillary services to the network  

Science Journals Connector (OSTI)

Abstract Majority of the wind power resources are typically sited at remote locations in power networks and generated power is transmitted through rural transmission corridors to load centres. With increased penetration level of the wind generation there is an increased requirement to provide ancillary services from distributed wind power resources, hence they are operated under different control strategies to provide ancillary services to the network. The control strategies and capability characteristics will significant impact on voltage fluctuations in distribution networks. This paper presents a comparative analysis between different wind generator control strategies (i.e. power factor control strategy, voltage control strategy and reactive power dispatch strategy) on network voltage fluctuations during variable wind conditions while considering extended reactive power capability (i.e. with both generator and power electronic converter reactive power capabilities) for the doubly-fed induction generator (DFIG). Voltage fluctuations are analysed using real wind data measured at a DFIG based wind farm, and the wind farm model was verified against real measurements. Study has shown that voltage fluctuations are exacerbated when wind generator is at mode transition (i.e. from power optimisation mode to power limitation mode). A sensitivity analysis has shown that voltage fluctuations are exacerbated due to the limitations of the reactive power capability of the DFIG, and the operating point of the DFIG power curve irrespective of the control strategy implemented at the wind generator. Furthermore, a mitigation strategy was developed as an integrated control scheme to the main control scheme in order to reduce voltage fluctuations due to wind power variations. However, effectiveness of the mitigation strategy is greatly affected by the reactive power capability of the DFIG, in particular during high wind turbulences.

Lasantha Meegahapola; Sarath Perera

2014-01-01T23:59:59.000Z

483

high  

Gasoline and Diesel Fuel Update (EIA)

0 0 Highlights International Oil Markets Prices. We have raised our world oil price projection by about $2 per barrel for this month because of assumed greater compliance by OPEC to targeted cuts, especially for the second quarter of 2000 (Figure 1). The expected decline in world petroleum inventories continues (Figure 2), and, given the generally stiff resolve of OPEC members to maintain production cuts, any sign of a turnaround in stocks may be postponed until later this year than previously assumed (Q3 instead of Q2). Our current estimate for the average import cost this past January is now $25 per barrel, a nearly $15-per-barrel increase from January 1999. Crude oil prices are expected to remain at relatively high levels for the first half of 2000, but

484

2428 IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 23, NO. 5, SEPTEMBER 2008 A Modular Strategy for Control and Voltage  

E-Print Network [OSTI]

, voltage balancing. I. INTRODUCTION WITH THE advancement of power electronics and emer- gence of new.1109/TPEL.2008.2002055 The CHB converters can be used as inverters in ac motor drives, high power2428 IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 23, NO. 5, SEPTEMBER 2008 A Modular Strategy

Paris-Sud XI, Université de

485

Direct observation of the intergrown {alpha}-phase in {beta}-TmAlB{sub 4} via high-resolution electron microscopy  

SciTech Connect (OSTI)

A TmAlB{sub 4} crystal with a ThMoB{sub 4}-type ({beta}-type) structure phase related to a hexagonal AlB{sub 2}-type structure was studied by electron diffraction and high-resolution electron microscopy. A high-resolution image clearly exhibits an intergrown lamellar structure of a YCrB{sub 4}-type ({alpha}-type) phase in the matrix of the {beta}-type phase in TmAlB{sub 4} crystal. The lamellar structure can be characterized by a tiling of deformed hexagons, which are a common structure unit in the {alpha}-type and {beta}-type structures. The intergrown nanostructure is considered to be attributed to the origin of low temperature anomalies in physical properties.

Yubuta, Kunio, E-mail: yubuta@imr.tohoku.ac.jp [Institute for Materials Research, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai 980-8577 (Japan); Mori, Takao [International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), Tsukuba 305-0044 (Japan); Leithe-Jasper, Andreas; Grin, Yuri [Max-Plank-Institut fuer Chemische Physik fester Stoeffe, 01187 Dresden (Germany); Okada, Shigeru [Department of Science and Engineering, Kokushikan University, Tokyo 154-8515 (Japan); Shishido, Toetsu [Institute for Materials Research, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai 980-8577 (Japan)

2009-08-05T23:59:59.000Z

486

MHK Technologies/Oregon State University Columbia Power Technologies Direct  

Open Energy Info (EERE)

State University Columbia Power Technologies Direct State University Columbia Power Technologies Direct Drive Point Absorber < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Oregon State University Columbia Power Technologies Direct Drive Point Absorber.jpg Technology Profile Primary Organization Oregon State University OSU Project(s) where this technology is utilized *MHK Projects/OSU Direct Drive Power Generation Buoys Technology Resource Click here Wave Technology Type Click here Point Absorber Technology Readiness Level Click here TRL 1-3: Discovery / Concept Definition / Early Stage Development & Design & Engineering Technology Description When the coil experiences a changing magnetic field created by the heaving magnets voltage is generated Technology Dimensions

487

Minimization of voltage deviation and power losses in power networks using Pareto optimization methods  

Science Journals Connector (OSTI)

Voltage regulation is an important task in electrical engineering for controlling node voltages in a power network. A widely used solution for the problem of voltage regulation is based on adjusting the taps in under load tap changers (ULTCs) power transformers ... Keywords: Multi-objective optimization, Power distribution network, Power losses, Under load tap changers, Voltage regulation

Francisco G. Montoya; Raúl Baños; Consolación Gil; Antonio Espín; Alfredo Alcayde; Julio Gómez

2010-08-01T23:59:59.000Z

488

Requirements for a Standard Test to Rate the Durability of PV Modules at System Voltage (Presentation)  

SciTech Connect (OSTI)

Degradation modes in photovoltaic modules under system bias voltage stress are described and classified.

Hacke, P.; Terwilliger, K.; Glick, S.; Kempe, M.; Kurtz, S.; Bennett, I.; Kloos, M.

2011-02-01T23:59:59.000Z

489

Elevated voltage level I.sub.DDQ failure testing of integrated circuits  

DOE Patents [OSTI]

Burn in testing of static CMOS IC's is eliminated by I.sub.DDQ testing at elevated voltage levels. These voltage levels are at least 25% higher than the normal operating voltage for the IC but are below voltage levels that would cause damage to the chip.

Righter, Alan W. (Albuquerque, NM)

1996-01-01T23:59:59.000Z

490

Elevated voltage level I{sub DDQ} failure testing of integrated circuits  

DOE Patents [OSTI]

Burn in testing of static CMOS IC`s is eliminated by I{sub DDQ} testing at elevated voltage levels. These voltage levels are at least 25% higher than the normal operating voltage for the IC but are below voltage levels that would cause damage to the chip. 4 figs.

Righter, A.W.

1996-05-21T23:59:59.000Z

491

Fig. 1. Circuit diagram of LCC resonant inverter, HV-transformer and symmetrical three-stage voltage multiplier rectifier [9] (Each of the shown diode consists of 10 single diodes connected in series with parallel snubbers and capacitors).  

E-Print Network [OSTI]

Böcker Paderborn University Power Electronics and Electrical Drives 33095 Paderborn, Germany E-Mail: {hu the circuit diagram of the power supply generating the positive half-wave of the test voltage: The zero, industrial control, modeling, reduced-order systems. I. INTRODUCTION Mobile (HV) high voltage test generators

Paderborn, Universität

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