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Note: This page contains sample records for the topic "high voltage large" 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 new VME based high voltage power supply for large experiments  

SciTech Connect

A new VME based high voltage power supply has been developed for the D{O} experiment at Fermilab. There are three types of supplies delivering up to {plus_minus}5.6 kV at 1.0 mA or +2.0 kV at 3.0 mA with a set accuracy of 1.5 V and extremely low voltage ripples. Complete computer control has allowed many special features to be developed for the supply, including user-defined control land monitor groups, variable ramp rates, and advanced histogram and graphic functions. 3 refs.

Ahn, S.C.; Angstadt, R.D.; Droege, T.F.; Johnson, M.E.; MacKinnon, B.A.; McNulty, S.E.; Shea, M.F.; Thompson, R.N.; Watson, M.M. [Fermi National Accelerator Lab., Batavia, IL (United States); Franzini, P. [Columbia Univ., New York, NY (United States); Jones, A.A. [Superconducting Super Collider Lab., Dallas, TX (United States); Lopez, M.L. [La Plata Univ. Nacional (Argentina); Wimpenny, S.J.; Yang, M.J. [California Univ., Riverside, CA (United States)

1991-11-01T23:59:59.000Z

2

A new VME based high voltage power supply for large experiments  

Science Conference Proceedings (OSTI)

A new VME based high voltage power supply has been developed for the D{O} experiment at Fermilab. There are three types of supplies delivering up to {plus minus}5.6 kV at 1.0 mA or +2.0 kV at 3.0 mA with a set accuracy of 1.5 V and extremely low voltage ripples. Complete computer control has allowed many special features to be developed for the supply, including user-defined control land monitor groups, variable ramp rates, and advanced histogram and graphic functions. 3 refs.

Ahn, S.C.; Angstadt, R.D.; Droege, T.F.; Johnson, M.E.; MacKinnon, B.A.; McNulty, S.E.; Shea, M.F.; Thompson, R.N.; Watson, M.M. (Fermi National Accelerator Lab., Batavia, IL (United States)); Franzini, P. (Columbia Univ., New York, NY (United States)); Jones, A.A. (Superconducting Super Collider Lab., Dallas, TX (United States)); Lopez, M.L. (La Plata Univ. Nacional (Argentina)); Wimpenny, S.J.; Yang, M.J

1991-11-01T23:59:59.000Z

3

HIGH VOLTAGE GENERATOR  

DOE Patents (OSTI)

A generator for producing relatively large currents at high voltages is described. In general, the invention comprises a plurality of capacitors connected in series by a plurality of switches alternately disposed with the capacitors. The above-noted circuit is mounted for movement with respect to contact members and switch closure means so that a load device and power supply are connected across successive numbers of capacitors, while the other capacitors are successively charged with the same power supply.

Schwemin, A.J.

1959-03-17T23:59:59.000Z

4

HIGH VOLTAGE GENERATOR  

DOE Patents (OSTI)

A generator is presented for producing relatively large currents at high voltages. In general, the invention comprises a plurality of capacitors connected in series by a plurality of switches alternately disposed with the capacitors. The circuit is mounted for movement with respect to contact members and switch closure means so that a load device and power supply are connected across successive numbers of capacitors, while the other capacitors are successively charged with the same power supply.

Schwemin, A.J.

1959-03-17T23:59:59.000Z

5

HIGH VOLTAGE ION SOURCE  

DOE Patents (OSTI)

A device is described for providing a source of molecular ions having a large output current and with an accelerated energy of the order of 600 kv. Ions are produced in an ion source which is provided with a water-cooled source grid of metal to effect maximum recombination of atomic ions to molecular ions. A very high accelerating voltage is applied to withdraw and accelerate the molecular ions from the source, and means are provided for dumping the excess electrons at the lowest possible potentials. An accelerating grid is placed adjacent to the source grid and a slotted, grounded accelerating electrode is placed adjacent to the accelerating grid. A potential of about 35 kv is maintained between the source grid and accelerating grid, and a potential of about 600 kv is maintained between the accelerating grid and accelerating electrode. In order to keep at a minimum the large number of oscillating electrons which are created when such high voltages are employed in the vicinity of a strong magnetic field, a plurality of high voltage cascaded shields are employed with a conventional electron dumping system being employed between each shield so as to dump the electrons at the lowest possible potential rather than at 600 kv.

Luce, J.S.

1960-04-19T23:59:59.000Z

6

HIGH VOLTAGE GENERATOR  

DOE Patents (OSTI)

This patent relates to high voltage supply circuits adapted for providing operating voltages for GeigerMueller counter tubes, and is especially directed to an arrangement for maintaining uniform voltage under changing conditions of operation. In the usual power supply arrangement for counter tubes the counter voltage is taken from across the power supply output capacitor. If the count rate exceeds the current delivering capaciiy of the capacitor, the capacitor voltage will drop, decreasing the counter voltage. The present invention provides a multivibrator which has its output voltage controlled by a signal proportional to the counting rate. As the counting rate increases beyond the current delivering capacity of the capacitor, the rectified voltage output from the multivibrator is increased to maintain uniform counter voltage.

Zito, G.V.

1959-04-21T23:59:59.000Z

7

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.

Stringfield, R.M.; Wheat, R.M. Jr.

1989-02-21T23:59:59.000Z

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 variable diameter insulator  

DOE Patents (OSTI)

A high voltage feedthrough assembly (10) having a tubular insulator (15) extending between the ground plane ring (16) and the high voltage ring (30). The insulator (15) is made of Pyrex and decreases in diameter from the ground plane ring (16) to the high voltage ring (30), producing equipotential lines almost perpendicular to the wall (27) of the insulator (15) to optimize the voltage-holding capability of the feedthrough assembly (10).

Vanecek, David L. (Martinez, CA); Pike, Chester D. (Pinole, CA)

1984-01-01T23:59:59.000Z

11

High voltage feedthrough bushing  

DOE Patents (OSTI)

A feedthrough bushing for a high voltage diode provides for using compression sealing for all sealing surfaces. A diode assembly includes a central conductor extending through the bushing and a grading ring assembly circumferentially surrounding and coaxial with the central conductor. A flexible conductive plate extends between and compressively seals against the central conductor and the grading ring assembly, wherein the flexibility of the plate allows inner and outer portions of the plate to axially translate for compression sealing against the central conductor and the grading ring assembly, respectively. The inner portion of the plate is bolted to the central conductor for affecting sealing. A compression beam is also bolted to the central conductor and engages the outer portion of the plate to urge the outer portion toward the grading ring assembly to obtain compression sealing therebetween.

Brucker, J.P.

1991-12-31T23:59:59.000Z

12

Low power, scalable multichannel high voltage controller  

DOE Patents (OSTI)

A low voltage control circuit is provided for individually controlling high voltage power provided over bus lines to a multitude of interconnected loads. An example of a load is a drive for capillary channels in a microfluidic system. Control is distributed from a central high voltage circuit, rather than using a number of large expensive central high voltage circuits to enable reducing circuit size and cost. Voltage is distributed to each individual load and controlled using a number of high voltage controller channel switches connected to high voltage bus lines. The channel switches each include complementary pull up and pull down photo isolator relays with photo isolator switching controlled from the central high voltage circuit to provide a desired bus line voltage. Switching of the photo isolator relays is further controlled in each channel switch using feedback from a resistor divider circuit to maintain the bus voltage swing within desired limits. Current sensing is provided using a switched resistive load in each channel switch, with switching of the resistive loads controlled from the central high voltage circuit.

Stamps, James Frederick (Livermore, CA); Crocker, Robert Ward (Fremont, CA); Yee, Daniel Dadwa (Dublin, CA); Dils, David Wright (Fort Worth, TX)

2006-03-14T23:59:59.000Z

13

Low power, scalable multichannel high voltage controller  

DOE Patents (OSTI)

A low voltage control circuit is provided for individually controlling high voltage power provided over bus lines to a multitude of interconnected loads. An example of a load is a drive for capillary channels in a microfluidic system. Control is distributed from a central high voltage circuit, rather than using a number of large expensive central high voltage circuits to enable reducing circuit size and cost. Voltage is distributed to each individual load and controlled using a number of high voltage controller channel switches connected to high voltage bus lines. The channel switches each include complementary pull up and pull down photo isolator relays with photo isolator switching controlled from the central high voltage circuit to provide a desired bus line voltage. Switching of the photo isolator relays is further controlled in each channel switch using feedback from a resistor divider circuit to maintain the bus voltage swing within desired limits. Current sensing is provided using a switched resistive load in each channel switch, with switching of the resistive loads controlled from the central high voltage circuit.

Stamps, James Frederick (Livermore, CA); Crocker, Robert Ward (Fremont, CA); Yee, Daniel Dadwa (Dublin, CA); Dils, David Wright (Fort Worth, TX)

2008-03-25T23:59:59.000Z

14

High frequency breakdown voltage  

SciTech Connect

This report contains information about the effect of frequency on the breakdown voltage of an air gap at standard pressure and temperature, 76 mm Hg and O{degrees}C, respectively. The frequencies of interest are 47 MHz and 60 MHz. Additionally, the breakdown in vacuum is briefly considered. The breakdown mechanism is explained on the basis of collision and ionization. The presence of the positive ions produced by ionization enhances the field in the gap, and thus determines the breakdown. When a low-frequency voltage is applied across the gap, the breakdown mechanism is the same as that caused by the DC or static voltage. However, when the frequency exceeds the first critical value f{sub c}, the positive ions are trapped in the gap, increasing the field considerably. This makes the breakdown occur earlier; in other words, the breakdown voltage is lowered. As the frequency increases two decades or more, the second critical frequency, f{sub ce}, is reached. This time the electrons start being trapped in the gap. Those electrons that travel multiple times across the gap before reaching the positive electrode result in an enormous number of electrons and positive ions being present in the gap. The result is a further decrease of the breakdown voltage. However, increasing the frequency does not decrease the breakdown voltage correspondingly. In fact, the associated breakdown field intensity is almost constant (about 29 kV/cm).The reason is that the recombination rate increases and counterbalances the production rate, thus reducing the effect of the positive ions` concentration in the gap. The theory of collision and ionization does not apply to the breakdown in vacuum. It seems that the breakdown in vacuum is primarily determined by the irregularities on the surfaces of the electrodes. Therefore, the effect of frequency on the breakdown, if any, is of secondary importance.

Chu, Thanh Duy

1992-03-01T23:59:59.000Z

15

High-voltage-compatible, fully depleted CCDs  

E-Print Network (OSTI)

result of this high-voltage requirement, we have taken a di?voltage is necessary in order to meet the PSF requirementsrequirements for SNAP have resulted in a need to operate at substrate bias voltages

2006-01-01T23:59:59.000Z

16

High voltage photovoltaic power converter  

DOE Patents (OSTI)

An array of independently connected photovoltaic cells on a semi-insulating substrate contains reflective coatings between the cells to enhance efficiency. A uniform, flat top laser beam profile is illuminated upon the array to produce electrical current having high voltage. An essentially wireless system includes a laser energy source being fed through optic fiber and cast upon the photovoltaic cell array to prevent stray electrical signals prior to use of the current from the array. Direct bandgap, single crystal semiconductor materials, such as GaAs, are commonly used in the array. Useful applications of the system include locations where high voltages are provided to confined spaces such as in explosive detonation, accelerators, photo cathodes and medical appliances.

Haigh, Ronald E. (Arvada, CO); Wojtczuk, Steve (Cambridge, MA); Jacobson, Gerard F. (Livermore, CA); Hagans, Karla G. (Livermore, CA)

2001-01-01T23:59:59.000Z

17

TRANSISTOR HIGH VOLTAGE POWER SUPPLY  

DOE Patents (OSTI)

High voltage, direct current power supplies are described for use with battery powered nuclear detection equipment. The particular advantages of the power supply described, are increased efficiency and reduced size and welght brought about by the use of transistors in the circuit. An important feature resides tn the employment of a pair of transistors in an alternatefiring oscillator circuit having a coupling transformer and other circuit components which are used for interconnecting the various electrodes of the transistors.

Driver, G.E.

1958-07-15T23:59:59.000Z

18

Comparative High Voltage Impulse Measurement  

Science Conference Proceedings (OSTI)

... substrate and surrounded by insulating oil; the low ... the amplitudes of the voltage peaks that are ... The uncertainties in the peak output voltages for the ...

2013-04-19T23:59:59.000Z

19

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

20

HIGH VOLTAGE, HIGH CURRENT SPARK GAP SWITCH  

DOE Patents (OSTI)

A high voltage and current spark gap switch comprising two main electrodes insulatingly supported in opposed spaced relationship and a middle electrode supported medially between the main electrodes and symmetrically about the median line of the main electrodes is described. The middle electrode has a perforation aligned with the median line and an irradiation electrode insulatingly supported in the body of the middle electrode normal to the median line and protruding into the perforation. (AEC)

Dike, R.S.; Lier, D.W.; Schofield, A.E.; Tuck, J.L.

1962-04-17T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage large" 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

Characterisation of the VELO High Voltage System  

E-Print Network (OSTI)

The high voltage system supplies the bias voltage to the 88 silicon sensors which comprise the LHCb Vertex Locator (VELO). This note describes the results of the tests which have been performed on the hardware of the high voltage system of the VELO. Each individual test detailed in this note corresponds to a specific requirement of the system. These requirements arise primarily from ensuring the safety of the silicon sensors and the quality of the data taken from the VELO modules. The tests performed are in four categories: normal operation of the high voltage system; verification of its stability under operation; discussion of its behaviour in failure modes; and details of operation at low voltage. Noteworthy issues, identified through the tests, include the behaviour of the high voltage modules at voltages below 9V, the current limit that can be applied during ramping of the voltage, and the speed with which the voltage is cut during failures of the system. The results of these tests provide high confidence that the high voltage system can be safely used and demonstrate that low noise is produced by the power supplies. LHCb Public Note, LHCb-2008-009Contents 1

Barinjaka Rakotomiaramanana; Chris Parkes; Lars Eklund

2008-01-01T23:59:59.000Z

22

Characterisation of the VELO High Voltage System  

E-Print Network (OSTI)

The high voltage system supplies the bias voltage to the 88 silicon sensors which comprise the LHCb Vertex Locator (VELO). This note describes the results of the tests which have been performed on the hardware of the high voltage system of the VELO. Each individual test detailed in this note corresponds to a specific requirement of the system. These requirements arise primarily from ensuring the safety of the silicon sensors and the quality of the data taken from the VELO modules. The tests performed are in four categories: normal operation of the high voltage system; vercation of its stability under operation; discussion of its behaviour in failure modes; and details of operation at low voltage. Noteworthy issues, identified through the tests, include the behaviour of the high voltage modules at voltages below 9V, the current limit that can be applied during ramping of the voltage, and the speed with which the voltage is cut during failures of the system. The results of these tests provide high confidence th...

Rakotomiaramanana, B; Eklund, L

2008-01-01T23:59:59.000Z

23

Characterisation of the VELO High Voltage System  

E-Print Network (OSTI)

The high voltage system supplies the bias voltage to the 88 silicon sensors which comprise the LHCb Vertex Locator (VELO). This note describes the results of the tests which have been performed on the hardware of the high voltage system of the VELO. Each individual test detailed in this note corresponds to a specific requirement of the system. These requirements arise primarily from ensuring the safety of the silicon sensors and the quality of the data taken from the VELO modules. The tests performed are in four categories: normal operation of the high voltage system; verification of its stability under operation; discussion of its behaviour in failure modes; and details of operation at low voltage. Noteworthy issues, identified through the tests, include the behaviour of the high voltage modules at voltages below 9V, the current limit that can be applied during ramping of the voltage, and the speed with which the voltage is cut during failures of the system. The results of these tests provide high confidence...

Rakotomiaramanana, B; Eklund, L

2008-01-01T23:59:59.000Z

24

High Voltage Safety Act | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

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

25

High Voltage Test Apparatus for a Neutron EDM Experiment and Lower Limit on the Dielectric Strength of Liquid Helium at Large Volumes  

E-Print Network (OSTI)

A new search for a permanent electric dipole moment (EDM) of the neutron is underway using ultracold neutrons produced and held in a bath of superfluid helium. Attaining the target sensitivity requires maintaining an electric field of several tens of kilovolts per centimeter across the experimental cell, which is nominally 7.5 cm wide and will contain about 4 liters of superfluid. The electrical properties of liquid helium are expected to be sufficient to meet the design goals, but little is known about these properties for volumes and electrode spacings appropriate to the EDM experiment. Furthermore, direct application of the necessary voltages from an external source to the experimental test cell is impractical. An apparatus to amplify voltages in the liquid helium environment and to test the electrical properties of the liquid for large volumes and electrode spacings has been constructed. The device consists of a large-area parallel plate capacitor immersed in a 200 liter liquid helium dewar. Preliminary results show the breakdown strength of normal state liquid helium is at least 90 kV/cm at these volumes, at the helium vapor pressure corresponding to 4.38 K. These fields hold for more than 11 hours with leakage currents less than 170 pA (about 20% of the maximum tolerable in the EDM experiment). The system is also found to be robust against anticipated radiation backgrounds. Preliminary results for superfluid show that fields of at least 30 kV/cm can be sustained at the volumes required for the EDM experiment, about 60% of the design goal. These results are likely limited by the low pressure that must be maintained above the superfluid bath.

J. C. Long; P. D. Barnes; J. G. Boissevain; D. J. Clark; M. D. Cooper; J. J. Gomez; S. K. Lamoreaux; R. E. Mischke; S. I. Penttila

2006-03-27T23:59:59.000Z

26

High-voltage-compatible, fully depleted CCDs  

SciTech Connect

We describe charge-coupled device (CCD) developmentactivities at the Lawrence Berkeley National Laboratory (LBNL).Back-illuminated CCDs fabricated on 200-300 mu m thick, fully depleted,high-resistivity silicon substrates are produced in partnership with acommercial CCD foundry.The CCDs are fully depleted by the application ofa substrate bias voltage. Spatial resolution considerations requireoperation of thick, fully depleted CCDs at high substrate bias voltages.We have developed CCDs that are compatible with substrate bias voltagesof at least 200V. This improves spatial resolution for a given thickness,and allows for full depletion of thicker CCDs than previously considered.We have demonstrated full depletion of 650-675 mu m thick CCDs, withpotential applications in direct x-ray detection. In this work we discussthe issues related to high-voltage operation of fully depleted CCDs, aswell as experimental results on high-voltage-compatible CCDs.

Holland, Stephen E.; Bebek, Chris J.; Dawson, Kyle S.; Emes, JohnE.; Fabricius, Max H.; Fairfield, Jessaym A.; Groom, Don E.; Karcher, A.; Kolbe, William F.; Palaio, Nick P.; Roe, Natalie A.; Wang, Guobin

2006-05-15T23:59:59.000Z

27

Contaminated Outdoor High Voltage Insulators  

Science Conference Proceedings (OSTI)

The external insulation of power lines and outdoor substations is a weak point in transmission systems. The insulation is particularly susceptible to failure if proper attention has not been given to its design, condition monitoring, and maintenance. In regions with high contamination levels, regular maintenance and the application of palliative measures can be critical to ensure that the system meets its outage performance targets. This can involve pure maintenance measures such as cleaning the insulato...

2009-12-22T23:59:59.000Z

28

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)

2008-07-15T23:59:59.000Z

29

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)

2007-01-09T23:59:59.000Z

30

High voltage VLF testing of power cables  

SciTech Connect

This publication describes a laboratory test program conducted with the objective to develop a test that would replace the existing dc withstand test. The article describes the methodology used to establish the voltage duration and magnitude of VLF (0.1 Hz) high voltage field tests suitable for crosslinked polyethylene (XLPE) insulated power cable. The results show that the voltage breakdown of laboratory aged XLPE cable at 0.1 Hz is approximately equal to that at 60 Hz, that proof tests at 0.1 Hz is approximately equal to that at 60 Hz, that proof tests at 0.1 Hz cause very little damage to the cable, and that 0.1 Hz testing appears to be a satisfactory alternate to dc testing. Preliminary values are suggested for voltage magnitude and time duration of cable acceptance, maintenance and proof tests at 0.1 Hz for XLPE cable rated up to 35 kV. A program is underway to similarly evaluate samples of service-aged XLPE cable; as well as to demonstrate the use of the preliminary test values at typical utility installations.

Eager, G.S.; Katz, C.; Fryszczyn, B. [Cable Technology Labs., Inc., New Brunswick, NJ (United States); Densley, J. [Ontario Hydro, Toronto, Ontario (Canada); Bernstein, B.S. [EPRI, Washington, DC (United States)

1997-04-01T23:59:59.000Z

31

Functionalized High Voltage Spinel Composite for High Power ...  

Science Conference Proceedings (OSTI)

Recently, spinel LiNi0.5Mn1.5O4 with high working voltage and long cycle life makes it become the one of most promising cathode for high power delivery.

32

Motor voltage high harmonics influence to efficient energy usage  

Science Conference Proceedings (OSTI)

Analysis of the effect of non-sinusoidal voltages on the three-phase induction motor is presented in the paper. When the induction motors are supplied by a rectangular shape of the voltage inverter with high levels of harmonic voltage (Uh,i ... Keywords: energy efficiency, harmonics, induction motor, non-sinusoidal voltage, power losses

Miloje M. Kostic; Branka B. Kostic

2011-07-01T23:59:59.000Z

33

Activated Sintering, Spark Plasma Sintering and High Voltage ...  

Science Conference Proceedings (OSTI)

Mar 4, 2013 ... Novel Synthesis and Consolidation of Powder Materials : Activated Sintering, Spark Plasma Sintering and High Voltage Electric Discharge...

34

High Voltage GaN Schottky Rectifiers  

SciTech Connect

Mesa and planar GaN Schottky diode rectifiers with reverse breakdown voltages (V{sub RB}) up to 550V and >2000V, respectively, have been fabricated. The on-state resistance, R{sub ON}, was 6m{Omega}{center_dot} cm{sup 2} and 0.8{Omega}cm{sup 2}, respectively, producing figure-of-merit values for (V{sub RB}){sup 2}/R{sub ON} in the range 5-48 MW{center_dot}cm{sup -2}. At low biases the reverse leakage current was proportional to the size of the rectifying contact perimeter, while at high biases the current was proportional to the area of this contact. These results suggest that at low reverse biases, the leakage is dominated by the surface component, while at higher biases the bulk component dominates. On-state voltages were 3.5V for the 550V diodes and {ge}15 for the 2kV diodes. Reverse recovery times were <0.2{micro}sec for devices switched from a forward current density of {approx}500A{center_dot}cm{sup -2} to a reverse bias of 100V.

CAO,X.A.; CHO,H.; CHU,S.N.G.; CHUO,C.-C.; CHYI,J.-I.; DANG,G.T.; HAN,JUNG; LEE,C.-M.; PEARTON,S.J.; REN,F.; WILSON,R.G.; ZHANG,A.P.

1999-10-25T23:59:59.000Z

35

Spark-plasma Sintering vs. High Voltage Electric Discharge ...  

Science Conference Proceedings (OSTI)

High voltage electric discharge consolidation (HVEDC) includes high axial pressure and discharge of the electrical energy stored in capacitors, thus enabling a...

36

Cascode buffer for monolithic voltage conversion operating at high input supply voltages  

E-Print Network (OSTI)

A high-to-low switching DC-DC converter that operates at input supply voltages up to two times as high as the maximum voltage permitted in a nanometer CMOS technology is proposed in this paper. The circuit technique is based on a cascode bridge that maintains the steady-state voltage differences among the terminals of all of the transistors within a range imposed by a specific fabrication technology. The proposed circuit technique permits the full integration of active and passive devices of a switching DC-DC converter with a high voltage conversion ratio in a standard low voltage CMOS process. An efficiency of 87.8 % is achieved for 3.6 volts to 0.9 volts conversion assuming

Volkan Kursun; Gerhard Schrom; Vivek K. De; Eby G. Friedman; Siva G. Narendra

2005-01-01T23:59:59.000Z

37

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...

38

High Voltage Electric Discharge Consolidation of Tantalum Powders  

Science Conference Proceedings (OSTI)

Abstract Scope, The high voltage electric discharge consolidation (HVEDC) is a promising method of the volumetric-porous body manufacturing, which can be...

39

(SPS) and High Voltage Electric Discharge Consolidation (HVEDC  

Science Conference Proceedings (OSTI)

Presentation Title, Inter-Particle Contact Phenomena in Spark-Plasma Sintering ( SPS) and High Voltage Electric Discharge Consolidation (HVEDC). Author(s)...

40

(SPS) and High Voltage Electric Discharge Consolidation (HVEDC)  

Science Conference Proceedings (OSTI)

Presentation Title, Local Heat Balance in Spark-plasma Sintering (SPS) and High Voltage Electric Discharge Consolidation (HVEDC). Author(s), Eugene...

Note: This page contains sample records for the topic "high voltage large" 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

Chronic Benzodiazepine Administration Potentiates High Voltage-Activated Calcium Currents  

E-Print Network (OSTI)

.aspetjournals.orgDownloadedfrom #12;other drugs of abuse has been reported to enhance high voltage-activated calcium channels (HVAs

Brand, Paul H.

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

A compact high voltage pulse generator  

SciTech Connect

A compact, easily transportable, pulse generator has been developed for a variety of applications that require a pulse duration in the range of 1 {mu} sec., voltages from 150 to 300 KV and current levels from 2,000 to 3,000 amps. The generator has a simple cylindrical configuration and modular construction to facilitate assembly and service. The generator may be operated single-pulse or repetitively at pulse repetition rates to 50 Hz in a burst mode.

Rohwein, G.J.; Babcock, S.R.

1994-07-01T23:59:59.000Z

44

Living and Working Safely Around High-Voltage Power Lines.  

Science Conference Proceedings (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

45

Planar LTCC transformers for high voltage flyback converters.  

SciTech Connect

This paper discusses the design and use of low-temperature (850 C to 950 C) co-fired ceramic (LTCC) planar magnetic flyback transformers for applications that require conversion of a low voltage to high voltage (> 100V) with significant volumetric constraints. Measured performance and modeling results for multiple designs showed that the LTCC flyback transformer design and construction imposes serious limitations on the achievable coupling and significantly impacts the transformer performance and output voltage. This paper discusses the impact of various design factors that can provide improved performance by increasing transformer coupling and output voltage. The experiments performed on prototype units demonstrated LTCC transformer designs capable of greater than 2 kV output. Finally, the work investigated the effect of the LTCC microstructure on transformer insulation. Although this paper focuses on generating voltages in the kV range, the experimental characterization and discussion presented in this work applies to designs requiring lower voltage.

Schofield, Daryl (NASCENT Technology Inc. , Watertown, SD); Schare, Joshua M.; Glass, Sarah Jill; Roesler, Alexander William; Ewsuk, Kevin Gregory; Slama, George (NASCENT Technology Inc. , Watertown, SD); Abel, Dave (NASCENT Technology Inc. , Watertown, SD)

2007-06-01T23:59:59.000Z

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

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

48

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

49

High-voltage air-core pulse transformers  

SciTech Connect

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

50

Optical control system for high-voltage terminals  

DOE Patents (OSTI)

An optical control system for the control of devices in the terminal of an electrostatic accelerator includes a laser that is modulated by a series of preselected codes produced by an encoder. A photodiode receiver is placed in the laser beam at the high-voltage terminal of an electrostatic accelerator. A decoder connected to the photodiode decodes the signals to provide control impulses for a plurality of devices at the high voltage of the terminal.

Bicek, John J. (Tinley Park, IL)

1978-01-01T23:59:59.000Z

51

Available Technologies: High Voltage Compatible, Fully ...  

APPLICATIONS OF TECHNOLOGY: Small pixel, scientific CCDs where good point spread function (PSF) is required; High quantum efficiency direct detection ...

52

Lipon Coatings for High Voltage and High Temperature Li-Ion ...  

use of high-capacity and high-voltage cathode materials, but charging to voltages approaching 4.5-5V invariably causes rapid loss of capacity with cycling.

53

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 the voltage of the output. The preferred embodiment also comprises a low voltage power supply for biasing the FETs at or near an operational voltage. 8 figs.

Christie, D.J.; Dallum, G.E.

1989-12-07T23:59:59.000Z

54

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

55

Planar LTCC transformers for high voltage flyback converters: Part II.  

Science Conference Proceedings (OSTI)

This paper is a continuation of the work presented in SAND2007-2591 'Planar LTCC Transformers for High Voltage Flyback Converters'. The designs in that SAND report were all based on a ferrite tape/dielectric paste system originally developed by NASCENTechnoloy, Inc, who collaborated in the design and manufacturing of the planar LTCC flyback converters. The output/volume requirements were targeted to DoD application for hard target/mini fuzing at around 1500 V for reasonable primary peak currents. High voltages could be obtained but with considerable higher current. Work had begun on higher voltage systems and is where this report begins. Limits in material properties and processing capabilities show that the state-of-the-art has limited our practical output voltage from such a small part volume. In other words, the technology is currently limited within the allowable funding and interest.

Schofield, Daryl (NASCENTechnology, Inc., Watertown, SD); Schare, Joshua M., Ph.D.; Slama, George (NASCENTechnology, Inc., Watertown, SD); Abel, David (NASCENTechnology, Inc., Watertown, SD)

2009-02-01T23:59:59.000Z

56

Design & Fabrication of a High-Voltage Photovoltaic Cell  

DOE Green Energy (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

57

High voltage series connected tandem junction solar battery  

DOE Patents (OSTI)

A high voltage series connected tandem junction solar battery which comprises a plurality of strips of tandem junction solar cells of hydrogenated amorphous silicon having one optical path and electrically interconnected by a tunnel junction. The layers of hydrogenated amorphous silicon, arranged in a tandem configuration, can have the same bandgap or differing bandgaps. The tandem junction strip solar cells are series connected to produce a solar battery of any desired voltage.

Hanak, Joseph J. (Lawrenceville, NJ)

1982-01-01T23:59:59.000Z

58

Gaseous insulators for high voltage electrical equipment  

DOE Patents (OSTI)

Gaseous insulators comprise compounds having high attachment cross sections for electrons having energies in the 0-1.3 electron volt range. Multi-component gaseous insulators comprise compounds and mixtures having overall high electron attachment cross sections in the 0-1.3 electron volt range and moderating gases having high cross sections for inelastic interactions with electrons of energies 1-4 electron volts. Suitable electron attachment components include hexafluorobutyne, perfluorobutene-2, perfluorocyclobutane, perfluorodimethylcyclobutane, perfluorocyclohexene, perfluoromethylcyclohexane, hexafluorobutadiene, perfluoroheptene-1 and hexafluoroazomethane. Suitable moderating gases include N.sub.2, CO, CO.sub.2 and H.sub.2. The gaseous insulating mixture can also contain SF.sub.6, perfluoropropane and perfluorobenzene.

Christophorou, Loucas G. (Oak Ridge, TN); James, David R. (Knoxville, TN); Pace, Marshall O. (Knoxville, TN); Pai, Robert Y. (Concord, TN)

1981-01-01T23:59:59.000Z

59

Gaseous insulators for high voltage electrical equipment  

DOE Patents (OSTI)

Gaseous insulators comprise compounds having high attachment cross sections for electrons having energies in the 0-1.3 electron volt range. Multi-component gaseous insulators comprise compounds and mixtures having overall high electron attachment cross sections in the 0-1.3 electron volt range and moderating gases having high cross sections for inelastic interactions with electrons of energies 1-4 electron volts. Suitable electron attachment components include hexafluorobutyne, perfluorobutene-2, perfluorocyclobutane, perfluorodimethylcyclobutane, perfluorocyclohexene, perfluoromethylcyclohexane, hexafluorobutadiene, perfluoroheptene-1 and hexafluoroazomethane. Suitable moderating gases include N.sub.2, CO, CO.sub.2 and H.sub.2. The gaseous insulating mixture can also contain SF.sub.6, perfluoropropane and perfluorobenzene.

Christophorou, Loucas G. (Oak Ridge, TN); James, David R. (Knoxville, TN); Pace, Marshall O. (Knoxville, TN); Pai, Robert Y. (Concord, TN)

1979-01-01T23:59:59.000Z

60

High-voltage crowbar circuit with cascade-triggered series ignitrons  

DOE Patents (OSTI)

A series string of ignitrons for switching a large current at high voltage to ground. Switching is initiated by means of a negative trigger pulse applied to the cathode of the lowest voltage level ignitron next to ground to draw ground current through diodes in the ignitor circuit. The trigger pulse is applied thereby to the next higher ignitron cathode and sequentially to the remainder of the ignitrons in the string through diodes in respective ignitor circuits. Full line voltage is held off of nonconducting diodes and ignitrons by means of varistors.

Baker, William R. (Orinda, CA)

1980-01-01T23:59:59.000Z

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We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

High-voltage crowbar circuit with cascade-triggered series ignitrons  

DOE Patents (OSTI)

A series string of ignitrons for switching a large current at high voltage to ground. Switching is initiated by means of a negative trigger pulse applied to the cathode of the lowest voltage level ignitron next to ground to draw ground current through diodes in the ignitor circuit. The trigger pulse is applied thereby to the next higher ignitron cathode and sequentially to the remainder of the ignitrons in the string through diodes in respective ignitor circuits. Full line voltage is held off of nonconducting diodes and ignitrons by means of varistors. 1 fig.

Baker, W.R.

1980-11-04T23:59:59.000Z

62

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

63

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

64

Experiment Hazard Class 13.0 - High Voltage  

NLE Websites -- All DOE Office Websites (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

65

Ultra-compact Marx-type high-voltage generator  

DOE Patents (OSTI)

An ultra-compact Marx-type high-voltage generator includes individual high-performance components that are closely coupled and integrated into an extremely compact assembly. In one embodiment, a repetitively-switched, ultra-compact Marx generator includes low-profile, annular-shaped, high-voltage, ceramic capacitors with contoured edges and coplanar extended electrodes used for primary energy storage; low-profile, low-inductance, high-voltage, pressurized gas switches with compact gas envelopes suitably designed to be integrated with the annular capacitors; feed-forward, high-voltage, ceramic capacitors attached across successive switch-capacitor-switch stages to couple the necessary energy forward to sufficiently overvoltage the spark gap of the next in-line switch; optimally shaped electrodes and insulator surfaces to reduce electric field stresses in the weakest regions where dissimilar materials meet, and to spread the fields more evenly throughout the dielectric materials, allowing them to operate closer to their intrinsic breakdown levels; and uses manufacturing and assembly methods to integrate the capacitors and switches into stages that can be arranged into a low-profile Marx generator.

Goerz, David A. (Brentwood, CA); Wilson, Michael J. (Modesto, CA)

2000-01-01T23:59:59.000Z

66

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

67

Control Techniques to Eliminate Voltage Emergencies in High Performance Processors  

E-Print Network (OSTI)

negligible impact on perfor­ mance and energy. With the ITRS roadmap predicting aggres­ sive drops in supply. At present it is difficult to design a high quality, low impedance power supply system, and industry trends in current variability, often re­ ferred to as the dI/dt problem, can cause supply voltage fluc­ tuations

Martonosi, Margaret

68

Control Techniques to Eliminate Voltage Emergencies in High Performance Processors  

E-Print Network (OSTI)

negligible impact on perfor- mance and energy. With the ITRS roadmap predicting aggres- sive drops in supply. At present it is difficult to design a high quality, low impedance power supply system, and industry trends in current variability, often re- ferred to as the dI/dt problem, can cause supply voltage fluc- tuations

Gupta, Rajiv

69

High Voltage Laboratory Testing of Femtosecond Laser Lightning Diversion  

Science Conference Proceedings (OSTI)

Lightning strikes cost the electric power industry an estimated 1 billion dollars annually in damage and lost revenue. One possible way of protecting critical and susceptible facilities from lightning strikes is to use lasers to trigger and divert lightning along a predetermined path. This report describes laboratory research on the use of ultrashort UV pulses and near IR pulses to trigger high voltage discharge.

1998-12-09T23:59:59.000Z

70

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

71

High voltage bipolar-CMOS structure using porous silicon  

DOE Patents (OSTI)

A method for integrating a silicon-on-insulator device and a bulk bipolar device on a semiconductor body. The invention simultaneously forms the two regions for the silicon-on-insulator device and the bipolar device. The invention enables a high voltage CMOS power device to be located on the same chip as a bipolar logic device enabling smart power devices.

Guilinger, T.R.; Kelly, M.J.; Tsao, S.S.

1990-01-01T23:59:59.000Z

72

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

SciTech Connect

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

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

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

75

Field Guide: Compressors for High-Voltage Circuit Breakers  

Science Conference Proceedings (OSTI)

High-voltage circuit breakers (HVCBs) perform essential protection and control functions on power transmission networks. Circuit breakers have multiple components that must operate in concert in order for the breaker to perform properly. If one component, such as the air or hydraulic system, does not operate correctly, the circuit breaker may misoperate or fail, possibly resulting in equipment damage or an outageboth expensive consequences. To help utilities prevent such undesirable events, this field gu...

2010-12-22T23:59:59.000Z

76

Field Guide: Compressors for High-Voltage Circuit Breakers  

Science Conference Proceedings (OSTI)

High-voltage circuit breakers (HVCBs) perform essential protection and control functions on power transmission networks. Circuit breakers have multiple components that must operate in concert in order for the breaker to perform properly. If one component, such as the air or hydraulic system, does not operate correctly, the circuit breaker may misoperate or fail, possibly resulting in equipment damage or an outageboth expensive consequences. To help ...

2012-12-14T23:59:59.000Z

77

High Voltage Direct Current (HVDC) Transmission Reference Book  

Science Conference Proceedings (OSTI)

The EPRI High-Voltage Direct Current (HVDC) Transmission Reference Book is a state-of-the-art guidebook that provides transmission companies with a comprehensive, single source of technical information and guidance for designing, building, operating, and extending the life of HVDC transmission systems. The book joins the landmark series of EPRI power delivery reference books. These comprehensive guidebookseach printed with a distinctive colored coverdocument and distill the ...

2012-12-31T23:59:59.000Z

78

High-Voltage Direct Current Line Conductor Optimization  

Science Conference Proceedings (OSTI)

Overhead transmission lines are designed to last for 40 years. Many ac lines in service today in North America are 70 or more years old. This survival rate is a result of conservative utility design practices and detailed product specifications. This reliability record has occurred despite a wide range of conductor types and sizes. In the present transmission system, there are far fewer high-voltage direct current (HVDC) lines, but those that have been designed and built have been similarly successful in...

2011-12-21T23:59:59.000Z

79

Field Guide: High-Voltage Circuit Breaker Compressors 2013 Update  

Science Conference Proceedings (OSTI)

High-voltage circuit breakers (HVCBs) perform essential protection and control functions on power transmission networks. Circuit breaker mechanisms have multiple components that must operate in concert in order for the breaker to perform properly. If one component, such as the air or hydraulic system, does not operate correctly, the circuit breaker may mis-operate or fail. A circuit breaker mis-operation may cause equipment damage and outagesboth ...

2013-12-19T23:59:59.000Z

80

Advanced Voltage Control Strategies for High Penetration of Distributed Generation  

Science Conference Proceedings (OSTI)

This research addresses advanced voltage control strategies for inverter-connected distributed generation. The emphasis is on photovoltaic (PV) generation, and results also apply to distributed wind, fuel cells, micro-turbines, and battery systems that are connected to the grid through an inverter. In related work, the Electric Power Research Institute (EPRI) identified a set of high-priority functions for distributed generation. These included reactive power control such as intelligent and autonomous vo...

2010-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage large" 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

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. 6 figs.

Renda, G.F.

1992-04-21T23:59:59.000Z

82

Advanced Gate Drive for the SNS High Voltage Converter Modulator  

SciTech Connect

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

83

High voltage design structure for high temperature superconducting device  

DOE Patents (OSTI)

In accordance with the present invention, modular corona shields are employed in a HTS device to reduce the electric field surrounding the HTS device. In a exemplary embodiment a fault current limiter module in the insulation region of a cryogenic cooling system has at least one fault current limiter set which employs a first corona shield disposed along the top portion of the fault current limiter set and is electrically coupled to the fault current limiter set. A second corona shield is disposed along the bottom portion of the fault current limiter set and is electrically coupled to the fault current limiter set. An insulation barrier is disposed within the insulation region along at least one side of the fault current limiter set. The first corona shield and the second corona shield act together to reduce the electric field surrounding the fault limiter set when voltage is applied to the fault limiter set.

Tekletsadik, Kasegn D. (Rexford, NY)

2008-05-20T23:59:59.000Z

84

Distribution System Voltage Performance Analysis for High-Penetration Photovoltaics  

DOE Green Energy (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

85

Curing system for high voltage cross linked cables  

DOE Patents (OSTI)

This invention makes extruded, vulcanized, high voltage cables insulated with thermosetting compounds at much higher rates of production and with superior insulation of reduced thickness and with reduced cavities or voids in the insulation. As the cable comes from an extruder, it passes into a curing chamber with a heat booster that quickly raises the insulation to a temperature at which it is cured much more quickly than with steam heating of the prior art. A high temperature liquid in contact with the insulation maintains the high temperature; and because of the greater curing heat, the cable can travel through the curing chamber at a faster rate and into a cooling tube where it contacts with a cooling liquid under high pressure. The insulation compound is treated to reduce the size of cavities; and the high pressure maintained by the curing and cooling mediums prevent expansion of cavities before the insulation is set.

Bahder, George (Edison, NJ); Katz, Carlos (Edison, NJ); Bopp, Louis A. (Fair Haven, NJ)

1978-01-01T23:59:59.000Z

86

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

SciTech Connect

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

87

Induction of nuclear fission by high-voltage application  

E-Print Network (OSTI)

In nuclear power generation, fissile materials are mainly used. For example, $U^{235}$ is fissile and therefore quite essential for use of nuclear energy. However, the material $U^{235}$ has very small natural abundance less than 1 %. We should seek possibility of utilizing fissionable materials such as $U^{238}$ because natural abundance of such fissionable materials is generally much larger than fissile ones. In this paper, we show that thermal neutrons with vanishing kinetic energy can induce nuclear fission when high voltage is applied to fissionable materials. To obtain this result, we use the liquid-drop model for nuclei. Finally, we propose how fissionable materials can be utilized.

Hirokazu Maruyama

2007-11-20T23:59:59.000Z

88

Worldwide reliability surveys of high voltage circuit breakers  

Science Conference Proceedings (OSTI)

This article reports on the results of two CIGRE 13.06 Working Group worldwide surveys of the reliability of high voltage circuit breakers, 63 kV and above. The first inquiry included 78,000 breaker-years of ``in service data`` from 102 utilities in 22 countries during the years 1974--1977 and included all interrupting technologies. The second inquiry included 70,708 breaker-years from 132 utilities in 22 countries for the years 1988--1991 and only included single-pressure SF6 breakers, because this is what most utilities are now buying. Thirty-one US utilities submitted data.

Heising, C.R.

1995-05-01T23:59:59.000Z

89

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

90

High Voltage Direct Current Live Line and Insulator Testing  

Science Conference Proceedings (OSTI)

This report has two main parts. The focus of the first part is on live work in overhead high-voltage direct current (HVDC) lines operating above 100 kV dc. It does not address issues related to lines for electric transport that typically operate below 60 kV dc worldwide. In addition, this first part of the report is not a detailed treatise on live work but, rather, addresses the main issues related to dc live work. More detailed information on the general topic of live work can be found in the references...

2011-12-23T23:59:59.000Z

91

High-Voltage Power Supply System for Laser Isotope Separation  

SciTech Connect

This report presents several concepts for Laser High-Voltage Power Supply (HVPS) Systems for a Laser Isotope Separation facility. Selection of equipments and their arrangement into operational systems is based on proven designs and on application concepts now being developed. This report has identified a number of alternative system arrangements and has provided preliminary cost estimates for each. The report includes a recommendation for follow-on studies that will further define the optimum Laser HVPS Systems. Brief descriptions are given of Modulator/Regulator circuit trade-offs, system control interfaces, and their impact on costs.

Ketaily, E.C.; Buckner, R.P.; Uhrik, R.L.

1979-06-26T23:59:59.000Z

92

An accurate continuous calibration system for high voltage current transformer  

SciTech Connect

A continuous calibration system for high voltage current transformers is presented in this paper. The sensor of this system is based on a kind of electronic instrument current transformer, which is a clamp-shape air core coil. This system uses an optical fiber transmission system for its signal transmission and power supply. Finally the digital integrator and fourth-order convolution window algorithm as error calculation methods are realized by the virtual instrument with a personal computer. It is found that this system can calibrate a high voltage current transformer while energized, which means avoiding a long calibrating period in the power system and the loss of power metering expense. At the same time, it has a wide dynamic range and frequency band, and it can achieve a high accuracy measurement in a complex electromagnetic field environment. The experimental results and the on-site operation results presented in the last part of the paper, prove that it can reach the 0.05 accuracy class and is easy to operate on site.

Tong Yue; Li Binhong [College of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan 430074, Hubei Province (China)

2011-02-15T23:59:59.000Z

93

Effect of Space Charge on Surface Insulation of High-Voltage Direct-Current Bushings  

Science Conference Proceedings (OSTI)

Operating data on bushings and post insulators for HVDC converter stations demonstrate that large-diameter insulators perform poorly when exposed to a combination of rain or fog and airborne contaminants. A technique that produces an intense space charge, resulting in corona at the high-voltage electrode of HVDC bushings, shows promise of improving flashover performance in some laboratory applications, but apparently has little effect under simulated service conditions.

1987-11-03T23:59:59.000Z

94

Dubal Cell Voltage Drop Initiatives towards Low Energy High ...  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, 2014 TMS Annual Meeting & Exhibition. Symposium , Aluminum Reduction Technology. Presentation Title, DUBAL CELL VOLTAGE...

95

High-voltage atmospheric breakdown across intervening rutile dielectrics.  

SciTech Connect

This report documents work conducted in FY13 on electrical discharge experiments performed to develop predictive computational models of the fundamental processes of surface breakdown in the vicinity of high-permittivity material interfaces. Further, experiments were conducted to determine if free carrier electrons could be excited into the conduction band thus lowering the effective breakdown voltage when UV photons (4.66 eV) from a high energy pulsed laser were incident on the rutile sample. This report documents the numerical approach, the experimental setup, and summarizes the data and simulations. Lastly, it describes the path forward and challenges that must be overcome in order to improve future experiments for characterizing the breakdown behavior for rutile.

Williamson, Kenneth Martin; Simpson, Sean; Coats, Rebecca Sue; Jorgenson, Roy Eberhardt; Hjalmarson, Harold Paul; Pasik, Michael Francis

2013-09-01T23:59:59.000Z

96

A high-voltage low-power DC-DC buck regulator for automotive applications  

Science Conference Proceedings (OSTI)

This work presents a High-Voltage Low-Power CMOS DC-DC buck regulator for automotive applications. The overall system, including the high and low voltage analog devices, the power MOS and the low voltage digital devices, was realized in the Austriamicrosystems ... Keywords: DC-DC regulator, buck converter, current control, low quiscent current, pulse frequency modulation

G. Pasetti; L. Fanucci; R. Serventi

2010-03-01T23:59:59.000Z

97

CMOS flash analog-to-digital converter for high speed and low voltage applications  

Science Conference Proceedings (OSTI)

A CMOS flash analog-to-digital converter (ADC) designed for high speed and low voltage is presented. Using the Threshold Inverter Quantization (TIQ) comparator technique, a flash ADC can be applied to low supply voltage. A fat tree encoder that has signal ... Keywords: TIQ comparator, analog-to-digital converter, fat tree encoder, flash ADC, high speed, low voltage

Jincheol Yoo; Kyusun Choi; Jahan Ghaznavi

2003-04-01T23:59:59.000Z

98

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

99

Voltage spike detection in high field superconducting accelerator magnets  

SciTech Connect

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

100

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

Note: This page contains sample records for the topic "high voltage large" 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

Circuit for monitoring temperature of high-voltage equipment  

DOE Patents (OSTI)

This invention relates to an improved circuit for measuring temperature in a region at high electric potential and generating a read-out of the same in a region at lower potential. The circuit is specially designed to combine high sensitivity, stability, and accuracy. A major portion of the circuit situated in the high-potential region can take the form of an integrated circuit. The preferred form of the circuit includes an input section which is situated in the high-potential region and comprises a temperature-compensated thermocouple circuit for sensing temperature, an oscillator circuit for generating a train of ramp voltages whose rise time varies inversely with the thermocouple output, a comparator and switching circuit for converting the oscillator output to pulses whose frequency is proportional to the thermocouple output, and a light-emitting diode which is energized by these pulses. An optical coupling transmits the light pulses generated by the diode to an output section of the circuit, situated in a region at ground. The output section comprises means for converting the transmitted pulses to electrical pulses of corresponding frequency, means for amplifying the electrical pulses, and means for displaying the frequency of the same. The preferred embodiment of the overall circuit is designed so that the frequency of the output signal in hertz and tenths of hertz is equal to the sensed temperature in degrees and tenths of degrees.

Jacobs, Martin E. (Chillicothe, OH)

1976-01-01T23:59:59.000Z

102

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

DOE Green Energy (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

103

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

104

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

105

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

106

Electrochemical Windows of Sulfone-Based Electrolytes for High-Voltage Li-Ion Batteries  

Science Conference Proceedings (OSTI)

Further development of high-voltage lithium-ion batteries requires electrolytes with electrochemical windows greater than 5 V. Sulfone-based electrolytes are promising for such a purpose. Here we compute the electrochemical windows for experimentally tested sulfone electrolytes by different levels of theory in combination with various solvation models. The MP2 method combined with the polarizable continuum model is shown to be the most accurate method to predict oxidation potentials of sulfone-based electrolytes with mean deviation less than 0.29 V. Mulliken charge analysis shows that the oxidation happens on the sulfone group for ethylmethyl sulfone and tetramethylene sulfone, and on the ether group for ether functionalized sulfones. Large electrochemical windows of sulfone-based electrolytes are mainly contributed by the sulfone group in the molecules which helps lower the HOMO level. This study can help understand the voltage limits imposed by the sulfone-based electrolytes and aid in designing new electrolytes with greater electrochemical windows.

Shao, Nan [ORNL; Sun, Xiao-Guang [ORNL; Dai, Sheng [ORNL; Jiang, Deen [ORNL

2011-01-01T23:59:59.000Z

107

LARGE AREA NEGATIVE ION SOURCE FOR HIGH VOLTAGE NEUTRAL BEAMS  

E-Print Network (OSTI)

2. The metal is heated in the boiler (typically to 550C) totempera ture than the boiler to minimize the fraction ofbeen employed. 4.5) VALVE BOILER X L 7911-12695 B Fig. 2.

Poulsen, P.

2010-01-01T23:59:59.000Z

108

ESS 2012 Peer Review - Low Cost, Manufacturable High Voltage...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Storage for Power Flow Management and Voltage Control on an 11kV UK Distribution Network", 20th International Conference on Electricity Distribution, June 2009. S1 S2 C1 C2...

109

High power impulse magnetron sputtering: Current-voltage-time ...  

pauses between pulses !typically 20 ms". The nominal volt-age of the pulser was adjustable up to 1000 V. The arc threshold was set to 120 A. If the current exceeded this

110

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

111

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 summarize (more)

Rountree, Barry

2009-01-01T23:59:59.000Z

112

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

E-Print Network (OSTI)

The subject of radio-frequency interference (RFI) generated by high-voltage transmission lines has long been of both academic and commercial interest because of concerns about

Patrick C. Crane

2010-01-01T23:59:59.000Z

113

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

DOE Green Energy (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

114

Laser-Triggered Lightning Laboratory Tests: Preparation for Testing at Mississippi State University High-Voltage Laboratory  

Science Conference Proceedings (OSTI)

Lightning diversion using laser technology could be operationally used in the power industry to protect sensitive facilities such as nuclear power plants and critical substations, control centers, and customer facilities. This report provides results to date and plans for large-scale, high-voltage laboratory testing of laser-triggered lightning technology.

1998-01-15T23:59:59.000Z

115

A model for the critical voltage for electrical degradation of GaN high electron mobility transistors  

E-Print Network (OSTI)

We have found that there is a critical drain-to-gate voltage beyond which GaN high-electron mobility transistors start to degrade in electrical-stress experiments. The critical voltage depends on the detailed voltage biasing ...

Joh, Jungwoo

116

Degradation of Photovoltaic Modules Under High Voltage Stress in the Field: Preprint  

DOE Green Energy (OSTI)

The degradation in performance for eight photovoltaic (PV) modules stressed at high voltage (HV) is presented. Four types of modules--tandem-junction and triple-junction amorphous thin-film silicon, plus crystalline and polycrystalline silicon modules--were tested, with a pair of each biased at opposite polarities. They were deployed outdoors between 2001 and 2009 with their respective HV leakage currents through the module encapsulation continuously monitored with a data acquisition system, along with air temperature and relative humidity. For the first 5 years, all modules were biased continuously at fixed 600 VDC, day and night. In the last 2 years, the modules were step-bias stressed cyclically up and down in voltage between 10 and 600 VDC, in steps of tens to hundreds of volts. This allowed characterization of leakage current versus voltage under a large range of temperature and moisture conditions, facilitating determination of leakage paths. An analysis of the degradation is presented, along with integrated leakage charge. In HV operation: the bulk silicon modules degraded either insignificantly or at rates of 0.1%/yr higher than modules not biased at HV; for the thin-film silicon modules, the added loss rates are insignificant for one type, or 0.2%/yr-0.6%/yr larger for the other type.

del Cueto, J. A.; Rummel, S. R.

2010-08-01T23:59:59.000Z

117

Unlikely Combination of Experiments with a Novel High-Voltage CIGS Photovoltaic Array (Presentation)  

DOE Green Energy (OSTI)

The goals of this study are to: (1) parameterize current-voltage (I-V) performance over a wide range of illumination and temperatures: (a) 50-1150 W/m{sup 2} irradiance, 5-65 C; (b) obtain array temperature coefficients; and (c) quantify energy production; (2) investigate high-voltage leakage currents from the CIS modules in a high-voltage array: determine dependence on moisture, temperature, and voltage bias and ascertain corrosion problems if any; and (3) study long-term power and energy production stability.

del Cueto, J. A.; Sekulic, B. R.

2006-05-01T23:59:59.000Z

118

A low-power, high-bandwidth LDO voltage regulator with no external capacitor  

E-Print Network (OSTI)

A low-dropout (LDO) voltage regulator for low-power applications is designed without an external capacitor for compensation. The regulator has two stages, the first a folded cascode amplifier and the second a large pass ...

Ha, Miranda J. (Miranda Joy)

2008-01-01T23:59:59.000Z

119

High voltage bus and auxiliary heater control system for an electric or hybrid vehicle  

DOE Green Energy (OSTI)

A control system for an electric or hybrid electric vehicle includes a vehicle system controller and a control circuit having an electric immersion heater. The heater is electrically connected to the vehicle's high voltage bus and is thermally coupled to a coolant loop containing a heater core for the vehicle's climate control system. The system controller responds to cabin heat requests from the climate control system by generating a pulse width modulated signal that is used by the control circuit to operate the heater at a duty cycle appropriate for the amount of cabin heating requested. The control system also uses the heater to dissipate excess energy produced by an auxiliary power unit and to provide electric braking when regenerative braking is not desirable and manual braking is not necessary. The control system further utilizes the heater to provide a safe discharge of a bank of energy storage capacitors following disconnection of the battery or one of the high voltage connectors used to transmit high voltage operating power to the various vehicle systems. The control circuit includes a high voltage clamping circuit that monitors the voltage on the bus and operates the heater to clamp down the bus voltage when it exceeds a pre-selected maximum voltage. The control system can also be used to phase in operation of the heater when the bus voltage exceeds a lower threshold voltage and can be used to phase out the auxiliary power unit charging and regenerative braking when the battery becomes fully charged.

Murty, Balarama Vempaty (West Bloomfield, MI)

2000-01-01T23:59:59.000Z

120

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

Note: This page contains sample records for the topic "high voltage large" 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

Capabilities of the High Voltage Stress Test System at the Outdoor Test Facility  

DOE Green Energy (OSTI)

We illustrate the capabilities of the High Voltage Stress Test (HVST) which operates continuously in the array field east of the Outdoor Test Facility at the National Renewable Energy Laboratory. Because we know that photovoltaic (PV) modules generating electrical power in both residential and utility-scale array installations will develop high-voltage biases approaching 600 VDC and 1,000 VDC, respectively, we expect such high voltages will result in current leakage between cells and ground, typically through the frames or mounts. We know that inevitably such leakage currents are capable of producing electrochemical corrosion that adversely impacts long-term module performance. With the HVST, we stress or operate PV modules under high-voltage bias, to characterize their leakage currents under all prevailing ambient conditions and assess performance changes emanating from high-voltage stress. We perform this test both on single modules and an active array.

del Cueto, J. A.; Trudell, D.; Sekulic, W.

2005-11-01T23:59:59.000Z

122

Assessment and Evaluation of Next Generation High-Voltage DC TechnologiesPhase 2  

Science Conference Proceedings (OSTI)

As an established technology for bulk power transmission, high-voltage direct current (HVDC) power transmission is being used worldwide, and more than 100 schemes are operating at present. Advances in voltage sourced converter (VSC) technologies and power electronic devices with use of insulated-gate bipolar transistors (IGBTs) will provide improved system performance and reliability. Also, the present highest operating voltage is +/- 800 kV as China and India are building +/- 800-kV lines. Anticipating ...

2009-12-17T23:59:59.000Z

123

SECONDARY ELECTRON TRAJECTORIES IN HIGH-GRADIENT VACUUM INSULATORS WITH FAST HIGH-VOLTAGE PULSES  

Science Conference Proceedings (OSTI)

Vacuum insulators composed of alternating layers of metal and dielectric, known as high-gradient insulators (HGIs), have been shown to withstand higher electric fields than conventional insulators. Primary or secondary electrons (emitted from the insulator surface) can be deflected by magnetic fields from external sources, the high-current electron beam, the conduction current in the transmission line, or the displacement current in the insulator. These electrons are deflected either toward or away from the insulator surface and this affects the performance of the vacuum insulator. This paper shows the effects of displacement current from short voltage pulses on the performance of high gradient insulators. Generally, vacuum insulator failure is due to surface flashover, initiated by electrons emitted from a triple junction. These electrons strike the insulator surface thus producing secondary electrons, and can lead to a subsequent electron cascade along the surface. The displacement current in the insulator can deflect electrons either toward or away from the insulator surface, and affects the performance of the vacuum insulator when the insulator is subjected to a fast high-voltage pulse. Vacuum insulators composed of alternating layers of metal and dielectric, known as high-gradient insulators (HGIs), have been shown to withstand higher electric fields than conventional insulators. HGIs, being tolerant of the direct view of high-current electron and ion beams, and having desirable RF properties for accelerators, are a key enabling technology for the dielectric-wall accelerators (DWA) being developed at Lawrence Livermore National Laboratory (LLNL). Characteristically, insulator surface breakdown thresholds go up as the applied voltage pulse width decreases. To attain the highest accelerating gradient in the DWA, short accelerating voltage pulses are only applied locally, along the HGI accelerator tube, in sync with the charged particle bunch, and the effects of displacement current on trajectories of electrons emitted from HGI surface are particularly interesting. This paper presents simulated electron trajectories experiencing either constant or short-duration applied voltage pulses. Comparisons of these trajectories clearly indicate the importance of the voltage pulse shape, especially the rise time, in the flashover initiation process for HGIs.

Chen, Y; Blackfield, D; Nelson, S D; Poole, B

2010-04-21T23:59:59.000Z

124

Summary of transient high-voltage calculations for the FRX-C experiment  

Science Conference Proceedings (OSTI)

Calculations of the electrical circuit equations are performed over a wide range of parameters corresponding to the FRX-C field-reversed THETA-pinch experiment at Los Alamos. Without any plasma or external damping, serious voltage doubling and quadrupling of the main capacitor bank charge voltage are observed. These oscillating high voltages are found to be adequately suppressed by the strategic placement of external snubber circuitry. On the other hand, no doubling of the THETA-pinch preionization bank charge voltage is found. Calculations of the equations for the z-pinch preionization circuit are also performed.

Kewish, R.W. Jr.; Rej, D.J.

1982-06-01T23:59:59.000Z

125

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

126

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

127

Look-ahead voltage and load margin contingency selection functions for large-scale power systems  

SciTech Connect

Given the current operating condition (obtained from the real-time data), the near-term load demand at each bus (obtained from short-term load forecast), and the generation dispatch (say, based on economic dispatch), the authors present in this paper a load margin measure (MW and/or MVAR) to assess the system`s ability to withstand the forecasted load and generation variations. The authors also present a method to predict near-term system voltage profiles. The proposed look-ahead measure and the proposed voltage prediction are then applied to contingency selections for the near-term power system in terms of load margins to collapse and of the bus voltage magnitudes. They evaluate the proposed load-ahead measure and the voltage profile prediction on several power systems including a 1169-bus power system with 53 contingencies with promising results.

Chiang, H.D.; Wang, C.S.; Flueck, A.J. [Cornell Univ., Ithaca, NY (United States). School of Electrical Engineering

1997-02-01T23:59:59.000Z

128

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

129

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.

Duckworth, Douglas C. (Knoxville, TN); Marcus, R. Kenneth (Clemson, SC); Donohue, David L. (Vienna, AT); Lewis, Trousdale A. (Oak Ridge, TN)

1994-01-01T23:59:59.000Z

130

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

SciTech Connect

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

131

Telecontrol of Ultra-High Voltage Electron Microscope over Global IPv6 Network  

Science Conference Proceedings (OSTI)

Osaka University has an Ultra-High VoltageElectron Microscope (UHVEM) which can provide highquality specimen images for worldwide researchers. Forusability improvements, we have worked on thetelecontrol of the UHVEM. In this paper, we would liketo introduce ...

Toyokazu Akiyama; Shinji Shimojo; Shojiro Nishio; Yoshinori Kitatsuji; Steven Peltier; Thomas Hutton; Fang-Pang Lin

2003-01-01T23:59:59.000Z

132

Piezoelectric based high voltage power simulator for implantation  

Science Conference Proceedings (OSTI)

It is based on resonant method that allows the piezoelectric transformer to generate a ... The device is small and with high power density and high efficiency

133

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

134

3430 IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY, VOL. 61, NO. 8, OCTOBER 2012 Experimental Validation of High-Voltage-Ratio  

E-Print Network (OSTI)

Validation of High-Voltage-Ratio Low-Input-Current-Ripple Converters for Hybrid Fuel Cell Supercapacitor

Simões, Marcelo Godoy

135

High voltage bus and auxiliary heater control system for an electric or hybrid vehicle  

DOE Patents (OSTI)

A control system for an electric or hybrid electric vehicle includes a vehicle system controller and a control circuit having an electric immersion heater. The heater is electrically connected to the vehicle's high voltage bus and is thermally coupled to a coolant loop containing a heater core for the vehicle's climate control system. The system controller responds to cabin heat requests from the climate control system by generating a pulse width modulated signal that is used by the control circuit to operate the heater at a duty cycle appropriate for the amount of cabin heating requested. The control system also uses the heater to dissipate excess energy produced by an auxiliary power unit and to provide electric braking when regenerative braking is not desirable and manual braking is not necessary. The control system further utilizes the heater to provide a safe discharge of a bank of energy storage capacitors following disconnection of the battery or one of the high voltage connectors used to transmit high voltage operating power to the various vehicle systems. The control circuit includes a high voltage clamping circuit that monitors the voltage on the bus and operates the heater to clamp down the bus voltage when it exceeds a pre-selected maximum voltage. The control system can also be used to phase in operation of the heater when the bus voltage exceeds a lower threshold voltage and can be used to phase out the auxiliary power unit charging and regenerative braking when the battery becomes fully charged.

Murty, Balarama Vempaty (West Bloomfield, MI)

2000-01-01T23:59:59.000Z

136

Operational Results of Pulse Shaping Techniques for the High Voltage Convertor Modulator  

Science Conference Proceedings (OSTI)

The High Voltage Converter Modulators (HVCMs) are used to power the RF klystrons used throughout the accelerator systems at Spallation Neutron Source (SNS). The output voltage of the HVCM has significant droop and ripple which, combined with low level RF (LLRF) system limitations, affect performance and efficiency of accelerator cavities. In conjunction with the progress in development of the new HVCM controller, different pulse modulation techniques were implemented and studied on the test modulator. This paper discusses the results of implementation of frequency modulation and phase modulation on output voltage. Operational data, including full average power operation, of test modulator is also discussed. Future plans for the new modulation scheme will be presented.

Patel, Gunjan P [ORNL; Anderson, David E [ORNL; Solley, Dennis J [ORNL; Wezensky, Mark W [ORNL

2012-01-01T23:59:59.000Z

137

GaAs series connected photovoltaic converters for high voltage capacitor charging applications  

DOE Green Energy (OSTI)

This report describes the design features of series connected photovoltaic arrays which will be required to charge capacitors to relatively high (400V) voltages in time periods on the order of 1 microsecond. The factors which determine the array voltage and the capacitor charge time are given. Individual element junction designs, along with an interconnect scheme, and a semiconductor process to realize them are presented. Finally, the input laser optical required to meet the requirements is determined.

Rose, B.H.

1997-09-01T23:59:59.000Z

138

High-voltage DC transmission: a power electronics workhorse  

Science Conference Proceedings (OSTI)

Thyristor-based HVDC converter technology is used for highly reliable power transfer across natural or national boundaries or between AC systems designed for different frequencies or incompatible frequency controls. The author discusses the benefits ...

N. G. Hingorani

1996-04-01T23:59:59.000Z

139

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

SciTech Connect

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

140

The progress and challenges of threshold voltage control of high-k/metal-gated devices for advanced technologies (Invited Paper)  

Science Conference Proceedings (OSTI)

This paper discusses recent progress in and challenges of threshold voltage control for advanced high-k/metal-gated (HKMG) devices. It presents the impact on threshold voltage (V"t) control of incorporating La and Al into HKMG devices. A dipole moment ... Keywords: CMOS, Capping layer, EOT, High-k, Metal gate, Threshold voltage control

Hsing-Huang Tseng; Paul Kirsch; C. S. Park; Gennadi Bersuker; Prashant Majhi; Muhammad Hussain; Raj Jammy

2009-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage large" 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

Oxidation Potentials of Functionalized Sulfone Solvents for High-Voltage Li-Ion Batteries: A Computational Study  

Science Conference Proceedings (OSTI)

New electrolytes with large electrochemical windows are needed to meet the challenge for high-voltage Li-ion batteries. Sulfone as an electrolyte solvent boasts of high oxidation potentials. Here we examine the effect of multiple functionalization on sulfone's oxidation potential. We compute oxidation potentials for a series of sulfone-based molecules functionalized with fluorine, cyano, ester, and carbonate groups by using a quantum chemistry method within a continuum solvation model. We find that multifunctionalization is a key to achieving high oxidation potentials. This can be realized through either a fluorether group on a sulfone molecule or sulfonyl fluoride with a cyano or ester group.

Shao, Nan [ORNL; Sun, Xiao-Guang [ORNL; Dai, Sheng [ORNL; Jiang, Deen [ORNL

2012-01-01T23:59:59.000Z

142

Experimental Results from Droop Compensation for the High Voltage Converter Modulators  

Science Conference Proceedings (OSTI)

The High Voltage Convertor Modulators are used to power the RF klystrons used throughout the linear accelerator at the Spallation Neutron Source. The output voltage of the modulator has significant voltage droop and ripple which, combined with low level RF system limitations, affect performance and stability of the accelerator cavities. In conjunction with the progress in the development of the new controller, different modulation techniques were implemented and studied on the test modulator. This paper discusses experimental results from implementation of different modulation schemes has on the modulator output voltage pulse. Thermal measurements were carried out to determine the effect of these modulations schemes on long term reliability of the modulator. Future plans are also discussed.

Patel, Gunjan P [ORNL; Anderson, David E [ORNL; Peplov, Vladimir V [ORNL; Saethre, Robert B [ORNL; Solley, Dennis J [ORNL; Wezensky, Mark W [ORNL

2013-01-01T23:59:59.000Z

143

Field Guide Updates for 2011: Volume 1 - Compressors for High-Voltage Circuit Breakers, Volume 2 - Lubrication of High-Voltage Circu it Breakers  

Science Conference Proceedings (OSTI)

High-voltage circuit breakers (HVCBs) perform essential protection and control functions on power transmission networks. Circuit breakers have multiple components that must operate in concert in order for the breaker to perform properly. If one component, such as the air or hydraulic system, does not operate correctly, the circuit breaker may misoperate or fail, possibly resulting in equipment damage or an outageboth expensive consequences. To help utilities prevent such undesirable events, this field gu...

2011-12-12T23:59:59.000Z

144

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

145

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

SciTech Connect

GENI Project: GE is developing electricity transmission hardware that could connect distributed renewable energy sources, like wind farms, directly to the grideliminating 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 grids 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

146

Unlikely Combination of Experiments With a Novel High-Voltage CIGS Photovoltaic Array: Preprint  

DOE Green Energy (OSTI)

A new high-voltage array comprising bipolar strings of copper indium gallium diselenide (CIGS) photovoltaic (PV) modules was inaugurated in 2005. It is equipped with a unique combination of tests, which likely have never before been deployed simultaneously within a single array: full current-voltage (I-V) traces, high-voltage leakage current measurements, and peak-power tracking or temporal stepped-bias profiling. The array nominally produces 1 kW power at 1 sun. The array's electrical characteristics are continuously monitored and controlled with a programmable electronic load interfaced to a data acquisition system (DAS), that also records solar and meteorological data. The modules are mounted with their frames electrically isolated from earth ground, in order to facilitate measurement of the leakage currents that arise between the high voltage bias developed in the series-connected cells and modules and their mounting frames. Because the DAS can perform stepped biasing of the array as a function of time, synchronous detection of the leakage current data with alternating bias is available. Leakage current data and their dependence on temperature and voltage are investigated. Array power data are analyzed across a wide range of varying illuminations and temperatures from the I-V traces. Array performance is also analyzed from an energy output perspective using peak-power tracking data.

del Cueto, J. A.; Sekulic, B. R.

2006-05-01T23:59:59.000Z

147

Cooperative frequency control with a multi-terminal high-voltage DC network  

Science Conference Proceedings (OSTI)

We consider frequency control in power systems made of several non-synchronous AC areas connected by a multi-terminal high-voltage direct current (HVDC) grid. We propose two HVDC control schemes to make the areas collectively react to power imbalances, ... Keywords: Decentralized control, Frequency control, HVDC systems, Power system control

Alain Sarlette; Jing Dai; Yannick Phulpin; Damien Ernst

2012-12-01T23:59:59.000Z

148

LPAT: An interactive simulation tool for assessing the lightning performance of Hellenic high voltage transmission lines  

Science Conference Proceedings (OSTI)

The paper presents the Lightning Performance Assessment Tool (LPAT), an interactive simulation tool which assesses the lightning performance of high voltage transmission lines. The LPAT design was based on a recently published methodology that has been ... Keywords: Lightning performance, Optical transient density, Overhead transmission lines, Simulation, Software tool, User interface

P. Karampelas; L. Ekonomou; S. Panetsos; G. E. Chatzarakis

2011-01-01T23:59:59.000Z

149

Instantaneous Rainfall Rate: Its Measurement and Its Influence on High-Voltage Transmission Lines  

Science Conference Proceedings (OSTI)

When a high-voltage transmission line is exposed to rain there is generally a small amount of corona activity at the surface of the conductors. This activity usually results in a power loss and the generation of audible and radio noise. While the ...

Harold Kirkham

1980-01-01T23:59:59.000Z

150

Magnetic lens apparatus for a low-voltage high-resolution electron microscope  

DOE Patents (OSTI)

A lens apparatus in which a beam of charged particles of low accelerating voltage is brought to a focus by a magnetic field, the lens being situated behind the target position. The lens comprises an electrically-conducting coil arranged around the axis of the beam and a magnetic pole piece extending along the axis of the beam at least within the space surrounded by the coil. The lens apparatus comprises the sole focusing lens for high-resolution imaging in a low-voltage scanning electron microscope.

Crewe, Albert V. (Palos Park, IL)

1996-01-01T23:59:59.000Z

151

THE COST OF MAINTENANCE TRANSFER UNDER LOAD TAP OF THE TRANSFORMERS POWER OF EXTRA HIGH VOLTAGE THE ELETRONORTE.  

E-Print Network (OSTI)

??In this work a methodology for reduction of maintenance cost in the on-load tap changers (OLTC) of extra high voltage is proposed. The methodology is (more)

RAIMUNDO NONATO ROSA FILHO

2005-01-01T23:59:59.000Z

152

A Study On High Voltage AC Power Transmission Line Electric And Magnetic Field Coupling With Nearby Metallic Pipelines.  

E-Print Network (OSTI)

??In the recent years, there has been a trend to run metallic pipelines carrying petroleum products and high voltage AC power lines parallel to each (more)

Gupta, Abhishek

2006-01-01T23:59:59.000Z

153

Table 1. Design specifications of ultra-high speed PM motor. Supply voltage (V) 12  

E-Print Network (OSTI)

Analysis of Ultra-High Speed Permanent-Magnet Motor Masaru Kano, and Toshihiko Noguchi Department@vos.nagaokaut.ac.jp Abstract This paper describes a design of an ultra-high speed (UHS) permanent-magnet (PM) synchronous motor, a surface permanent-magnet (SPM) motor (150,000 r/min, 1.5 kW) fed by a low voltage battery (12 V

Fujimoto, Hiroshi

154

Environmental and Potential Health Effects of High Voltage Direct Current Transmission Lines  

Science Conference Proceedings (OSTI)

High-voltage direct current (HVDC) technology plays an important but highly selective role in the U.S. power delivery system. It is a cost-effective technology for transferring bulk power over long distances, a critical technology for asynchronous grid interconnection, and the preferred technology for long-distance underwater cable transmission. Current interest in renovating the national grid for greater loads and higher reliability as well as unique applications for renewable energy projects, including...

2012-07-31T23:59:59.000Z

155

Design and Optimization of Low Voltage High Performance Dual Threshold CMOS Circuits  

E-Print Network (OSTI)

Reduction in leakage power has become an important concern in lowvoltage, lowpower and high performance applications. In this paper, we use dual threshold technique to reduce leakage power by assigning high threshold voltage to some transistors in non-critical paths, and using lowthreshold transistors in critical paths. In order to achieve the best leakage power saving under target performance constraints, an algorithm is presented for selecting and assigning an optimal high threshold voltage. A general standby leakage current model which has been veri#ed by HSPICE is used to estimate standby leakage power. Results show that dual threshold technique is good for power reduction during both standby and active modes. The standby leakage power savings for some ISCAS benchmarks can be more than 50#. 1 Introduction With the growing use of portable and wireless electronic systems, reduction in power consumption has become more and more importantintoday's VLSI circuit and system designs #1#, ...

Liqiong Wei; Zhanping Chen; Mark Johnson; Kaushik Roy; Vivek De

1998-01-01T23:59:59.000Z

156

Digital Architecture for Driving Large LED Arrays with Dynamic Bus Voltage Regulation and Phase Shifted PWM  

E-Print Network (OSTI)

. Y. Tsao, "Light Emitting Diodes (LEDs) fi OIDA Technology Roadmap Update 2002 Development/Graphics/00038951_0.pdf ~d system efficiency at [16] E. F. Schubert, Light-Emitting Diodes, 2nd Edition, Cambridge, "Development of High Power Green digital control driving Light Emitting Diode Chips", MRS Internet Journal

157

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

Science Conference Proceedings (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

158

CRYOGENIC LIFETIME TESTS ON A COMMERCIAL EPOXY RESIN HIGH VOLTAGE BUSHING  

SciTech Connect

High-temperature superconducting (HTS) power devices operating in liquid nitrogen frequently require high-voltage bushings to carry the current leads from the superconducting windings to the room temperature grid connections. Oak Ridge National Laboratory is collaborating with Waukesha Electric Systems, SuperPower, and Southern California Edison to develop and demonstrate an HTS utility power transformer. Previous dielectric high voltage tests in support of this program have been carried out in test cryostats with commercial epoxy resin bushings from Electro Composites Inc. (ECI). Though the bushings performed well in these short-term tests, their long-term operation at high voltage in liquid nitrogen needs to be verified for use on the utility grid. Long-term tests are being carried out on a sample 28-kV-class ECI bushing. The bushing has a monolithic cast, cycloaliphatic resin body and is fire- and shatter-resistant. The test cryostat is located in an interlocked cage and is energized at 25 kVac around the clock. Liquid nitrogen (LN) is automatically refilled every 9.5 hours. Partial discharge, capacitance, and leakage resistance tests are periodically performed to check for deviations from factory values. At present, over 2400 hours have been accumulated with no changes in these parameters. The tests are scheduled to run for four to six months.

Schwenterly, S W [ORNL; Pleva, Ed [Waukesha Electric Systems, Waukesha, WI; Ha, Tam T [ORNL

2012-01-01T23:59:59.000Z

159

EPRI High-Voltage Direct Current (HVDC) Transmission Reference Book: Interim Report  

Science Conference Proceedings (OSTI)

The EPRI High-Voltage Direct Current (HVDC) Transmission Reference Book is a state-of-the-art guidebook that provides transmission companies with a comprehensive, single source of technical information and guidance for designing, building, operating, and extending the life of HVDC transmission systems. The book joins the landmark series of EPRI power delivery reference books. These comprehensive guidebookseach printed with a distinctive colored coverdocument and distill the knowledge and experience of th...

2011-12-30T23:59:59.000Z

160

Field Guide: Compressors for High-Voltage Circuit Breakers, Optimized for Electronic Viewing  

Science Conference Proceedings (OSTI)

High-voltage circuit breakers perform essential protection and control functions on power transmission networks. A circuit breaker that fails to operate within its design time period may cause serious damage and extended outages. Proper maintenance of compressors can help to ensure that breakers operate reliably and can prevent premature failures. This field guide, which has been optimized for use on electronic devices such as smart phones and tablets, is intended to help utility field personnel properly...

2011-11-09T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage large" 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

Round-robin artificial contamination test on high voltage dc insulators  

Science Conference Proceedings (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

162

Proceedings: High Voltage Current Transformers and Bushings: Failure Prediction and Prevention Symposium  

Science Conference Proceedings (OSTI)

EPRI-sponsored research has identified key parameters indicative of condition and impending failure of oil-filled, high-voltage current transformers (HVCTs) and bushings. These findings will assist utilities to improve the monitoring of HVCTs and bushings, and to develop mitigation techniques to reduce the risk of catastrophic transformer failure. These proceedings present the results of this research and the experiences of other researchers worldwide.

1999-12-01T23:59:59.000Z

163

Field Guide: Lubrication of High-Voltage Circuit Breakers - 2013 Update  

Science Conference Proceedings (OSTI)

High-voltage circuit breakers (HVCBs) perform essential protection and control functions on power transmission networks. Circuit breaker mechanisms have multiple components that must operate in concert in order for the breaker to perform properly. If one component does not operate correctly, the circuit breaker may mis-operate or fail. A circuit breaker mis-operation may cause equipment damage and outagesboth expensive consequences. Proper lubrication ...

2013-12-19T23:59:59.000Z

164

Voltage stability limits for weak power systems with high wind penetration.  

E-Print Network (OSTI)

??Analysis of power system voltage stability has practical value in increasing wind penetration levels. As wind penetration levels increase in power systems, voltage stability challenges (more)

Tamimi, Ala

2011-01-01T23:59:59.000Z

165

Experimental Estimate of Beam Loading and Minimum rf Voltage for Acceleration of High Intensity Beam in the Fermilab Booster  

E-Print Network (OSTI)

The difference between the rf voltage seen by the beam and the accelerating voltage required to match the rate of change of the Booster magnetic field is used to estimate the energy loss per beam turn. Because the rf voltage (RFSUM) and the synchronous phase can be experimentally measured, they can be used to calculate the effective accelerating voltage. Also an RFSUM reduction technique has been applied to measure experimentally the RFSUM limit at which the beam loss starts. With information on beam energy loss, the running conditions, especially for the high intensity beam, can be optimized in order to achieve a higher intensity beam from the Fermilab Booster.

Yang, X; Norem, J; Yang, Xi

2004-01-01T23:59:59.000Z

166

Experimental estimate of beam loading and minimum rf voltage for acceleration of high intensity beam in the Fermilab Booster  

SciTech Connect

The difference between the rf voltage seen by the beam and the accelerating voltage required to match the rate of change of the Booster magnetic field is used to estimate the energy loss per beam turn. Because the rf voltage (RFSUM) and the synchronous phase can be experimentally measured, they can be used to calculate the effective accelerating voltage. Also an RFSUM reduction technique has been applied to measure experimentally the RFSUM limit at which the beam loss starts. With information on beam energy loss, the running conditions, especially for the high intensity beam, can be optimized in order to achieve a higher intensity beam from the Fermilab Booster.

Xi Yang; Charles M Ankenbrandt and Jim Norem

2004-04-01T23:59:59.000Z

167

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

Science Conference Proceedings (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

168

A high voltage pulsed power supply for capillary discharge waveguide applications  

Science Conference Proceedings (OSTI)

We present an all solid-state, high voltage pulsed power supply for inducing stable plasma formation (density {approx}10{sup 18} cm{sup -3}) in gas-filled capillary discharge waveguides. The pulser (pulse duration of 1 {mu}s) is based on transistor switching and wound transmission line transformer technology. For a capillary of length 40 mm and diameter 265 {mu}m and gas backing pressure of 100 mbar, a fast voltage pulse risetime of 95 ns initiates breakdown at 13 kV along the capillary. A peak current of {approx}280 A indicates near complete ionization, and the r.m.s. temporal jitter in the current pulse is only 4 ns. Temporally stable plasma formation is crucial for deploying capillary waveguides as plasma channels in laser-plasma interaction experiments, such as the laser wakefield accelerator.

Abuazoum, S.; Wiggins, S. M.; Issac, R. C.; Welsh, G. H.; Vieux, G.; Jaroszynski, D. A. [Department of Physics, Scottish Universities Physics Alliance, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Ganciu, M. [Low Temperature Plasma Department, National Institute of Lasers, Plasma and Radiation Physics, 077125, Magurele, Bucharest (Romania)

2011-06-15T23:59:59.000Z

169

High Voltage CMOS Control Interface for Astronomy - Grade Charged Coupled Devices  

E-Print Network (OSTI)

The Pan-STARRS telescope consists of an array of smaller mirrors viewed by a Gigapixel arrays of CCDs. These focal planes employ Orthogonal Transfer CCDs (OTCCDs) to allow on-chip image stabilization. Each OTCCD has advanced logic features that are controlled externally. A CMOS Interface Device for High Voltage has been developed to provide the appropiate voltage signal levels from a readout and control system designated STARGRASP. OTCCD chip output levels range from -3.3V to 16.7V, with two different output drive strenghts required depending on load capacitance (50pF and 1000pF), with 24mA of drive and a rise time on the order of 100ns. Additional testing ADC structures have been included in this chip to evaluate future functional additions for a next version of the chip.

Martin, Elena; Koga, Aaron; Ruckman, Larry; Onaka, Peter; Tonry, John; Lee, Aaron

2008-01-01T23:59:59.000Z

170

Feasibility of high-voltage systems for a very long drift in liquid argon TPCs  

E-Print Network (OSTI)

Designs of high-voltage (HV) systems for creating a drift electric field in liquid argon TPCs are reviewed. In ongoing experiments systems capable of approx. 100 kV are realised for a drift field of 0.5-1 kV/cm over a length of up to 1.5 m. Two of them having different approaches are presented: (1) the ICARUS-T600 detector having a system consisting of an external power supply, HV feedthroughs and resistive voltage degraders and (2) the ArDM-1t detector having a cryogenic Greinacher HV multiplier inside the liquid argon volume. For a giant scale liquid argon TPC, a system providing 2 MV may be required to attain a drift length of approx. 20 m. Feasibility of such a system is evaluated by extrapolating the existing designs.

Horikawa, S; Kaufmann, L; Laffranchi, M; Marchionni, A; Messina, M; Natterer, G; Rubbia, A

2010-01-01T23:59:59.000Z

171

Electric power high-voltage transmission lines: Design options, cost, and electric and magnetic field levels  

SciTech Connect

This report provides background information about (1) the electric and magnetic fields (EMFs) of high-voltage transmission lines at typical voltages and line configurations and (2) typical transmission line costs to assist on alternatives in environmental documents. EMF strengths at 0 {+-} 200 ft from centerline were calculated for ac overhead lines, and for 345 and 230-kV ac underground line and for a {+-}450-kV dc overhead line. Compacting and height sensitivity factors were computed for the variation in EMFs when line conductors are moved closer or raised. Estimated costs for the lines are presented and discussed so that the impact of using alternative strategies for reducing EMF strengths and the implications of implementing the strategies can be better appreciated.

Stoffel, J.B.; Pentecost, E.D.; Roman, R.D.; Traczyk, P.A.

1994-11-01T23:59:59.000Z

172

Novel Nonflammable Electrolytes for Secondary Magnesium Batteries and High Voltage Electrolytes for Electrochemcial Supercapacitors  

Science Conference Proceedings (OSTI)

Magnesium has been used successfully in primary batteries, but its use in rechargeable cells has been stymied by the lack of suitable non-aqueous electrolyte that can conduct Mg+2 species, combined with poor stripping and plating properties. The development of a suitable cathode material for rechargeable magnesium batteries has also been a roadblock, but a nonflammable electrolyte is key. Likewise, the development of safe high voltage electrochemical supercapaitors has been stymied by the use of flammable solvents in the liquid electrolyte; to wit, acetonitrile. The purpose of the research conducted in this effort was to identify useful compositions of magnesium salts and polyphosphate solvents that would enable magnesium ions to be cycled within a secondary battery design. The polyphosphate solvents would provide the solvent for the magnesium salts while preventing the electrolyte from being flammable. This would enable these novel electrolytes to be considered as an alternative to THF-based electrolytes. In addition, we explored several of these solvents together with lithium slats for use as high voltage electrolytes for carbon-based electrochemical supercapacitors. The research was successful in that: 1) Magnesium imide dissolved in a phosphate ester solvent that contains a halogented phosphate ester appears to be the preferred electrolyte for a rechargeable Mg cell. 2) A combination of B-doped CNTs and vanadium phosphate appear to be the cathode of choice for a rechargeable Mg cell by virtue of higher voltage and better reversibility. 3) Magnesium alloys appear to perform better than pure magnesium when used in combination with the novel polyphosphate electrolytes. Also, this effort has established that Phoenix Innovation??s family of phosphonate/phosphate electrolytes together with specific lithium slats can be used in supercapacitor systems at voltages of greater than 10V.

Dr. Brian Dixon

2008-12-30T23:59:59.000Z

173

A Tracker for the Mu3e Experiment based on High-Voltage Monolithic Active Pixel Sensors  

E-Print Network (OSTI)

The Mu3e experiment searches for the lepton flavour violating decay mu+ -> e+e-e+, aiming for a branching fraction sensitivity of 10^-16. This requires an excellent momentum resolution for low energy electrons, high rate capability and a large acceptance. In order to minimize multiple scattering, the amount of material has to be as small as possible. These challenges can be met with a tracker built from high-voltage monolithic active pixel sensors (HV-MAPS), which can be thinned to 50 um and which incorporate the complete read-out electronics on the sensor chip. To further minimise material, the sensors are supported by a mechanical structure built from 25 um thick Kapton foil and cooled with gaseous helium.

Berger, Niklaus; Bachmann, Sebastian; Kiehn, Moritz; Peri?, Ivan; Perrevoort, Ann-Kathrin; Philipp, Raphael; Schning, Andr; Stumpf, Kevin; Wiedner, Dirk; Windelband, Bernd; Zimmermann, Marco

2013-01-01T23:59:59.000Z

174

A Tracker for the Mu3e Experiment based on High-Voltage Monolithic Active Pixel Sensors  

E-Print Network (OSTI)

The Mu3e experiment searches for the lepton flavour violating decay mu+ -> e+e-e+, aiming for a branching fraction sensitivity of 10^-16. This requires an excellent momentum resolution for low energy electrons, high rate capability and a large acceptance. In order to minimize multiple scattering, the amount of material has to be as small as possible. These challenges can be met with a tracker built from high-voltage monolithic active pixel sensors (HV-MAPS), which can be thinned to 50 um and which incorporate the complete read-out electronics on the sensor chip. To further minimise material, the sensors are supported by a mechanical structure built from 25 um thick Kapton foil and cooled with gaseous helium.

Niklaus Berger; Heiko Augustin; Sebastian Bachmann; Moritz Kiehn; Ivan Peri?; Ann-Kathrin Perrevoort; Raphael Philipp; Andr Schning; Kevin Stumpf; Dirk Wiedner; Bernd Windelband; Marco Zimmermann

2013-09-30T23:59:59.000Z

175

High-voltage technology for the LASL implosion-heating experiment  

SciTech Connect

The implosion-heating power supply uses four 125-kV generators in series. Each generator consists of a fast 125-kV pulse-forming network made up of capacitors attached to a 1m-wide parallel-plate transmission line which is fed through multiple cables from a 2.5- mu F, 0.5- mu H Marx bank charged to 180 kV. To simplify construction it was decided to do without oil or water for high- voltage insulation and grading. The developments described here are: (1) a low- inductance connection between the 125-kV capacitors and the parallel-plate transmission line using an elastomer gasket capable of holding 200 kV; (2) edge flashover prevention by ballooning'' the sheet insulation, by which a 10-cm edge extension of insulation is capable of withstanding a 200-kV pulse for several microseconds; (3) using the edge flashover for over-voltage prevention; (4) grading of voltage along insulators with conducting plastic sheets to prevent flashover at the load switches and cable connections; and (51 capacitively graded insulating supports for the Marx banks. (auth)

Hammel, J.E.; Henins, I.; Marshall, J.; Sherwood, A.R.

1973-01-01T23:59:59.000Z

176

The commercial development of water repellent coatings for high voltage transmission lines  

SciTech Connect

The purpose of the Cooperative Research and Development Agreement (CRADA) between UT-Battelle, LLC and Southwire Company was to jointly develop a low cost, commercially viable, water-repellant anti-icing coating system for high voltage transmission lines. Icing of power lines and other structures caused by freezing rain events occurs annually in the United States, and leads to severe and prolonged power outages. These outages cause untold economic and personal distress for many American families and businesses. Researchers at the Department of Energy?s Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee have previously developed a set of superhydrophobic coatings with remarkable anti-icing properties that could potentially be sprayed or painted onto high-tension power lines and pylons. These coatings drastically reduce ice accumulation on these structures during freezing rain events. The project involved obtaining technical input, supplies and test high voltage cables from Southwire, along with the joint development of anti-icing coating techniques, which would result in a commercial license agreement between Southwire and ORNL, and potentially other companies requiring water repellent anti-icing coatings.

Hunter, S. R. [ORNL] [ORNL; Daniel, A. [Southwire Company] [Southwire Company

2013-10-31T23:59:59.000Z

177

The commercial development of water repellent coatings for high voltage transmission lines  

SciTech Connect

The purpose of the Cooperative Research and Development Agreement (CRADA) between UT-Battelle, LLC and Southwire Company was to jointly develop a low cost, commercially viable, water-repellant anti-icing coating system for high voltage transmission lines. Icing of power lines and other structures caused by freezing rain events occurs annually in the United States, and leads to severe and prolonged power outages. These outages cause untold economic and personal distress for many American families and businesses. Researchers at the Department of Energy s Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee have previously developed a set of superhydrophobic coatings with remarkable anti-icing properties that could potentially be sprayed or painted onto high-tension power lines and pylons. These coatings drastically reduce ice accumulation on these structures during freezing rain events. The project involved obtaining technical input, supplies and test high voltage cables from Southwire, along with the joint development of anti-icing coating techniques, which would result in a commercial license agreement between Southwire and ORNL, and potentially other companies requiring water repellent anti-icing coatings.

Hunter, Scott Robert [ORNL] [ORNL

2013-10-01T23:59:59.000Z

178

Market Manual (Draft rev 5 Clean) Transmission Grid- High Voltage Metering  

E-Print Network (OSTI)

1.1. The Market Rules allow metering installations to be placed on the high voltage (HV) grid on the supply side of the Defined Meter Point. 1.2. The Market Rules allow metering installations on the high voltage grid to be associated to more than one connection point or embedded connection point. 1.3. The Market Rules permit a metering installation to be registered in respect of more than one facility even though the meter point is not located at the defined meter points, provided that all transfers of energy at any points of supply or consumption for the facilities to which the metering installation relates are determined in a manner satisfactory to the IESO. 1.4. This arrangement permits a reduction in the number of metering installations by using a single HV metering installation to settle multiple connection points or embedded connection points to a single delivery point. This arrangement applies to both energy and transmission settlement. 1.5. Any adjustment between the metering installations and the normal location of the Delivery Point(s) may be by means of an adjustment formula, provided that all

unknown authors

2008-01-01T23:59:59.000Z

179

Sulfone-based electrolytes for high voltage li-ion batteries.  

Science Conference Proceedings (OSTI)

Sulfone-based electrolytes have been investigated as electrolytes for lithium-ion cells using high-voltage positive electrodes, such as LiMn{sub 2}O{sub 4} and LiNi{sub 0.5}Mn{sub 1.5}O{sub 4} spinels, and Li{sub 4}Ti{sub 5}O{sub 12} spinel as negative electrode. In the presence of imide salt (LiTFSI) and ethyl methyl sulfone or tetramethyl sulfone (TMS) electrolytes, the Li{sub 4}Ti{sub 5}O{sub 12}/LiMn{sub 2}O{sub 4} cell exhibited a specific capacity of 80 mAh g{sup -1} with an excellent capacity retention after 100 cycles. In a cell with high-voltage LiNi{sub 0.5}Mn{sub 1.5}O{sub 4} positive electrode and 1 M LiPF{sub 6} in TMS as electrolyte, the capacity reached 110 mAh g{sup -1} at the C/12 rate. When TMS was blended with ethyl methyl carbonate, the Li{sub 4}Ti{sub 5}O{sub 12}/LiNi{sub 0.5}Mn{sub 1.5}O{sub 4} cell delivered an initial capacity of 80 mAh g{sup -1} and cycled fairly well for 1000 cycles under 2C rate. The exceptional electrochemical stability of the sulfone electrolytes and their compatibility with the Li{sub 4}Ti{sub 5}O{sub 12} safer and stable anode were the main reason behind the outstanding electrochemical performance observed with high-potential spinel cathode materials. These electrolytes could be promising alternative electrolytes for high-energy density battery applications such as plug-in hybrid and electric vehicles that require a long cycle life.

Abouimrane, A.; Belharouak, I.; Amine, K. (Chemical Sciences and Engineering Division)

2009-05-01T23:59:59.000Z

180

EPRI High-Voltage Direct Current (HVDC) Reference Book: Chapter 24 - Operation and Maintenance of HVDC Systems  

Science Conference Proceedings (OSTI)

This report contains descriptions of the operation and maintenance (O&M) activities of traditional high-voltage direct current (HVDC) line commutated (thyristor-based) and voltage-sourced converter (VSC) transmission systems. Both long-distance transmission schemesincluding the transmission linesand back-to-back schemes are included. The various tasks involved in the O&M of HVDC systems are described at some length, and a range of estimates is given for the staff requirements to carry out these activitie...

2010-01-19T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage large" 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.


181

High Voltage MOSFET Gate/Bulk Driver Controller for a Microbattery Switch Matrix in a 0.35 m Microwave SOI Technology  

Science Conference Proceedings (OSTI)

Integrated microbatteries are being currently developed to act as a "micropower" source in microsatellites. The current and voltage rating of the microbattery is fixed. Certain highly miniaturized systems require higher voltages and currents. A switching ... Keywords: LDMOSFET, SOI, microbattery, micropower

Vinesh Sukumar; Mahmoud Alahmad; Kevin Buck; Herbert Hess; Harry Li; Dave Cox; Fadi Nessir Zghoul; Jeremy Jackson; Stephen Terry; Ben Blalock; M. M. Mojarradi; W. C. West; J. F. Whitacre

2005-09-01T23:59:59.000Z

182

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

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

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.

183

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

NLE Websites -- All DOE Office Websites (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

184

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

185

Large Lenses of Highly Saline Mediterranean Water  

Science Conference Proceedings (OSTI)

Isolated compact anticyclonic eddies or salt lenses were found in the Canary Basin. Hydrographic surveys of three such lenses show large anomalies of salinity and temperature (0.8, 2.5C). They are centered at 1100 m, have a vertical extent of ...

Laurence Armi; Walter Zenk

1984-10-01T23:59:59.000Z

186

Status of High Polarization DC High Voltage GaAs Photoguns  

SciTech Connect

This talk will review the state of the art of high polarization GaAs photoguns used worldwide. Subject matter will include drive laser technology, photocathode material, gun design, vacuum requirements and photocathode lifetime as a function of beam current. Recent results have demonstrated high current, 85% polarized beams with high reliability and long lifetime under operational conditions. Research initiatives for ensuring production of high average and peak current beams for future accelerator facilities such as ELIC and the ILC will be also discussed.

P. A. Adderley; J. Brittian; J. Clark; J. Grames; J. Hansknecht; J. McCarter; M. Poelker; M. L. Stutzman; R. Suleiman; K. E. L. Surles-Law

2007-08-01T23:59:59.000Z

187

PRESENT AND FUTURE TECHNOLOGY OF HIGH VOLTAGE SYSTEMS FOR NEUTRAL BEAM INJECTORS  

E-Print Network (OSTI)

the accel voltage reg ulation requirement could be relaxedVOLTAGE SWITCHES TUBES SCR ASSEMBLIES CROSSED-FIELD INTERRUPTERS MAGNETIC CORE ARC SNUEBER3 COMPUTERS FOR CONTROL AND DIAGNOSTICS OPERATIONAL REQUIREMENTSvoltage- regulated (flat-topped) to 1%. If good regulation Is not a prime requirement,

Baker, W.R.

2011-01-01T23:59:59.000Z

188

An Ultra-Compact Marx-Type High-Voltage Generator  

DOE Green Energy (OSTI)

This paper discusses the design of an ultra-compact, Marx-type, high-voltage generator. This system incorporates high-performance components that are closely coupled and integrated into an extremely compact assembly. Low profile, custom ceramic capacitors with coplanar extended electrodes provide primary energy storage. Low-inductance, spark-gap switches incorporate miniature gas cavities imbedded within the central region of the annular shaped capacitors, with very thin dielectric sections separating the energy storage capacitors. Carefully shaped electrodes and insulator surfaces are used throughout to minimize field enhancements, reduce fields at triple-point regions, and enable operation at stress levels closer to the intrinsic breakdown limits of the dielectric materials. Specially shaped resistors and inductors are used for charging and isolation during operation. Forward-coupling ceramic capacitors are connected across successive switch-capacitor-switch stages to assist in switching. Pressurized SF, gas is used for electrical insulation in the spark-gap switches and throughout the unit. The pressure housing is constructed entirely of dielectric materials, with segments that interlock with the low-profile switch bodies to provide an integrated support structure for all of the components. This ultra-compact Marx generator employs a modular design that can be sized as needed for a particular application. Units have been assembled with 4, 10, and 30 stages and operated at levels up to 100 kV per stage.

Goerz, D; Ferriera, T; Nelson, D; Speer, R; Wilson, M

2001-06-15T23:59:59.000Z

189

Ceramic end seal design for high temperature high voltage nuclear instrumentation cables  

DOE Patents (OSTI)

A coaxial, hermetically sealed end structure is described for electrical instrumentation cables. A generally tubular ceramic body is hermetically sealed within a tubular sheath which is in turn sealed to the cable sheath. One end of the elongated tubular ceramic insulator is sealed to a metal end cap. The other end of the elongated tubular insulator has an end surface which is shaped concave relative to a central conductor which extends out of this end surface. When the end seal is hermetically sealed to an instrumentation cable device and the central conductor is maintained at a high positive potential relative to the tubular metal sheath, the electric field between the central conductor and the outer sheath tends to collect electrons from the concave end surface of the insulator. This minimizes breakdown pulse noise generation when instrumentation potentials are applied to the central conductor.

Meiss, James D. (Berkeley, CA); Cannon, Collins P. (Kennewick, VA)

1979-01-01T23:59:59.000Z

190

Current-Voltage and Capacitance-Voltage characteristics of Pd ...  

Science Conference Proceedings (OSTI)

Presentation Title, Current-Voltage and Capacitance-Voltage characteristics of Pd ... Nonlocal Modeling in High Rate Deformation and Ductile Fracture of...

191

Effect of MOSFET threshold voltage variation on high-performance circuits  

E-Print Network (OSTI)

The driving force for the semiconductor industry growth has been the elegant scaling nature of CMOS technology. In future CMOS technology generations, supply and threshold voltages will have to continually scale to sustain ...

Narendra, Siva G. (Siva Gurusami), 1971-

2002-01-01T23:59:59.000Z

192

Assessment of research directions for high-voltage direct-current power systems. Final report  

Science Conference Proceedings (OSTI)

High voltage direct current (HVDC) power transmission continues to be an emerging technology nearly thirty years after its introduction into modern power systems. To date its use has been restricted to either specialized applications having identifiable economic advantages (e.g., breakeven distance) or, rarely, applications where decoupling is needed. Only recently have the operational advantages (e.g., power modulation) of HVDC been realized on operating systems. A research project whose objective was to identify hardware developments and, where appropriate, system applications which can exemplify cost and operational advantages of integrated ac/dc power systems is discussed. The three principal tasks undertaken were: assessment of equipment developments; quantification of operational advantages; and interaction with system planners. Interest in HVDC power transmission has increased markedly over the past several years, and many new systems are now being investigated. The dissemination of information about HVDC, including specifically the symposium undertaken for Task 3, is a critical factor in fostering an understanding of this important adjunct to ac power transmission.

Long, W F

1982-09-01T23:59:59.000Z

193

Research on Fault Diagnosis on High Voltage SF6 Circuit Breaker Based on the Db Wavelet and Fuzzy Theory  

Science Conference Proceedings (OSTI)

This dissertation aims at providing a quick and accurate fault diagnosis method for on high voltage SF6circuit breaker. This method indirectly monitors the functioning of the breaker by observing the electric current in the coil of its switch. The electrical ... Keywords: SF6 circuit breaker, monitor, wavelet transform, fuzzy theory

Li Yang; Zhuo Yang; Yang Lei; Kejie Dai; Weiming Guan

2012-05-01T23:59:59.000Z

194

A Value Proposition for Developing an Industry Database for High Voltage Circuit Breakers & CIM Data Objects for T&D  

Science Conference Proceedings (OSTI)

EPRI initiated work to develop databases for performance analysis and benchmarking in order to address issues of performance data availability, support industry efforts to maximize power delivery asset values, and optimize maintenance activities. With the successful development of an industrywide database for distribution cables and the extension of that work to power transformers, interest has turned to high-voltage circuit breakers (HVCBs).

2007-11-19T23:59:59.000Z

195

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

196

Characterization of the Li(Si)/CoS(2) couple for a high-voltage, high-power thermal battery  

DOE Green Energy (OSTI)

In order to determined the capabilities of a thermal battery with high-voltage and high-power requirements, a detailed characterization of the candidate LiSi/LiCl-LiBr-LiF/CoS{sub 2} electrochemical couple was conducted. The rate capability of this system was investigated using 0.75 inch-dia. and 1.25 inch-dia. single and multiple cells under isothermal conditions, where the cells were regularly pulsed at increasingly higher currents. Limitations of the electronic loads and power supplies necessitated using batteries to obtain the desired maximum current densities possible for this system. Both 1.25 inch-dia. and 3 inch-dia. stacks were used with the number of cells ranging from 5 to 20. Initial tests involved 1.25 inch-dia. cells, where current densities in excess of 15 A/cm{sup 2} (>200 W/cm{sup 2}) were attained with 20-cell batteries during 1-s pulses. In subsequent follow-up tests with 3 inch-dia., 10-cell batteries, ten 400-A 1-s pulses were delivered over an operating period often minutes. These tests formed the foundation for subsequent full-sized battery tests with 125 cells with this chemistry.

GUIDOTTI,RONALD A.; REINHARDT,FREDERICK W.

2000-02-01T23:59:59.000Z

197

High-performance verification of large concurrent systems  

E-Print Network (OSTI)

High-performance verification of large concurrent systems Elbie taKrpska Ph.D. Thesis VU University Systems Ph.D. Thesis Elzbieta Krepska VU University Amsterdam, 2012 #12;This research was funded by the VU. #12;VRIJE UNIVERSITEIT TOWARDS BIG BIOLOGY: HIGH-PERFORMANCE VERIFICATION OF LARGE CONCURRENT SYSTEMS

Bal, Henri E.

198

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

199

High voltage, fast turn-on and turn-off switch: Final report for period September 2, 1998 - March 17, 1999  

DOE Green Energy (OSTI)

The aspect to be investigated during this contract was an electron-beam triggered diamond switch to be used in high power modulators. Today's high power modulators require higher voltage switches than those developed to date. Specifically, the proposed 1 TeV linear collider, the NLC/ILC at the Stanford Linear Accelerator Center (SLAC), consists of two linacs with 6600 X-Band klystrons powered by 3300 high power modulators. These modulators require switches capable of handling 80 kV, switching 8 kA with pulse durations ranging from 2 ps (linac) to 6 {micro}s (pre-linac) with switching times <50 ns at pulse repetition frequencies up to 180 Hz. In addition the large number of switches and other components dictate a pulse to pulse jitter of <10 ns and a mean time between failures of at least 50,000 hours. The present approach is to use hydrogen filled thyratrons. While these switches meet the voltage and conduction current requirements they lack the required reliability (pulse to pulse jitter) and lifetime. Research to improve these aspects is in progress. A solid state switch inherently offers the required reliability and lifetime. However, Si-based switches developed to date are limited to about 5 kV and several must be stacked in series to deliver the required voltage. This further increases the already large parts count and compromises reliability and lifetime. A monolithic, solid state switch capable of meeting all the requirements for X-Band modulators would be ideal. DOE selected this proposal for a Phase 1 SBIR award and this final report describes the progress made during the contract.

Jochen Schein; Xiaoxi Xu; Niansheng Qi; Steven Gensler; Rahul Prasad; Mahadevan Krishnan

1999-04-10T23:59:59.000Z

200

PRESENT AND FUTURE TECHNOLOGY OF HIGH VOLTAGE SYSTEMS FOR NEUTRAL BEAM INJECTORS  

E-Print Network (OSTI)

savings tn the power conditioning transformers would result.power supply would be extremely simple, involving as major components only primary contactors, voltage-variable transformer,transformer reactance. For the LBL 160-kV, 75-A NBSTF Accel power

Baker, W.R.

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage large" 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

Real time prelocalisation of electrical defaults on high voltage underground cable (single-phase case)  

Science Conference Proceedings (OSTI)

This paper proposes an assistance tool to the prelocalisation of the insulation defaults affecting electrical single-phase cables by using voltage and current measurements available in source substation. An equivalent network modeling defaults to the ... Keywords: default distance, distributed parameters, insulation default, prelocalisation, sheath, underground cable

Thameur Aloui; Fathi Ben Amar; Nizar Derbel; Hsan Hadj Abdallah

2010-05-01T23:59:59.000Z

202

A new converter fault discrimination method for a 12-pulse high-voltage direct current system based on wavelet transform and Hidden Markov Models  

Science Conference Proceedings (OSTI)

The progressive development in high-voltage direct current (HVDC) transmission enhances the need to implement an efficient protection scheme to distinguish the minimum faulty part of the system and to relieve the stressed equipment. This paper proposes ... Keywords: Discrete Hidden Markov Models, converter faults, fault discrimination, high-voltage direct current, wavelet transform

Mohamad Tahan; Hassan Monsef; Shahrokh Farhangi

2012-06-01T23:59:59.000Z

203

EPRI Comments on a French Study of Residential Proximity to High-Voltage Power Lines and Childhood Leukemia  

Science Conference Proceedings (OSTI)

Results of a French case-control epidemiologic study of residential proximity to high-voltage power lines and risk of childhood acute leukemia were published in the British Journal of Cancer. The EPRI Comments provides background information on the study, summarizes the main results and discusses the studys strength and limitations. The EPRI Comments also highlights an ongoing EPRI-funded epidemiologic study in California that is expected to provide further insight ...

2013-04-23T23:59:59.000Z

204

High-Voltage Direct Current Corona Testing of Transmission Line Hardware and Insulator Assemblies: Development of Test Methodology  

Science Conference Proceedings (OSTI)

When specifying hardware for new high-voltage direct current (HVDC) lines or replacement hardware for existing HVDC lines utilities generally require that the hardware meet specific corona performance requirements.While standards and test methods exist for testing hardware used on HVAC systems, no such material is available for HVDC systems.HVAC tests are sometimes conducted on the hardware and the results obtained are then related to HVDC by utilizing the peak HVAC line to ...

2013-12-20T23:59:59.000Z

205

EPRI Comments on a UK Case-Control Study of Magnetic Fields from High Voltage Power Lines and Childhood Cancer  

Science Conference Proceedings (OSTI)

A paper, entitled "Childhood cancer and magnetic fields from high voltage power lines in England and Wales: a case-control study," was published in the British Journal of Cancer on September 28, 2010. The authors assessed the association between exposure to EMF from power lines at the address of birth and childhood cancer. The current paper provides additional results to a study published earlier from the same data set in 2005. These EPRI comments provide an overview of study findings, conclusions, stren...

2010-12-22T23:59:59.000Z

206

A monitor and control system for high voltage, gating, and triggering of a scintillating fiber active target  

SciTech Connect

A monitor and control system has been designed, constructed and tested at Notre Dame for the purpose of controlling all aspects of a Scintillating Fiber Acxtive Target system used in High Energy Physics Experimentation. The SFT Active Target system requires control of high voltages, gating, trigger counters, and monitoring. In addition, it resides in a radioactive area with very limited access. The control system uses a Leading Edge microcomputer, two specialized Z80-based processors, associated DACs, ADCs, discrete semiconductors, linear ICs and TTL and MECL logic. All of the hardware and software is custom-built; its design and performance is discussed.

Baumbaugh, B.; Bishop, J.; Gardner, R.W.; Mountain, R.J.; Ruchti, R.; Baumbaugh, A.; Knickerbocker, K.

1988-02-01T23:59:59.000Z

207

A monitor and control system for high voltage, gating, and triggering of a scintillating fiber active target  

SciTech Connect

A monitor and control system has been designed, constructed and tested at Notre Dame for the purpose of controlling all aspects of a Scintillating Fiber Active Target system used in High Energy Physics Experimentation. The SFT Active Target system requires control of high voltages, gating, trigger counters, and monitoring. In addition, it resides in a radioactive area with very limited access. The control system uses a Leading Edge microcomputer, two specialized Z80-based processors, associated DACs, ADCs, discrete semiconductors, linear ICs, and TTL and MECL logic. All of the hardware and software is custom-built; its design and performance is discussed. 5 refs., 4 figs.

Baumbaugh, B.; Bishop, J.; Gardner, R.W.; Mountain, R.J.; Ruchti, R.; Baumbaugh, A.; Knickerbocker, K.

1987-10-01T23:59:59.000Z

208

Determination of the cathode and anode voltage drops in high power low-pressure amalgam lamps  

Science Conference Proceedings (OSTI)

For the first time, cathode and anode drops of powerful low-pressure amalgam lamps were measured. The lamp discharge current is 3.2 A, discharge current frequency is 43 kHz, linear electric power is 2.4 W/cm. The method of determination of a cathode drop is based on the change of a lamp operating voltage at variation of the electrode filament current at constant discharge current. The total (cathode plus anode) drop of voltage was measured by other, independent ways. The maximum cathode fall is 10.8 V; the anode fall corresponding to the maximal cathode fall is 2.4 V. It is shown that in powerful low pressure amalgam lamps the anode fall makes a considerable contribution (in certain cases, the basic one) to heating of electrodes. Therefore, the anode fall cannot be neglected, at design an electrode and ballast of amalgam lamps with operating discharge current frequency of tens of kHz.

Vasilyak, L. M., E-mail: vasilyak@ihed.ras.ru [Russian Academy of Sciences, Joint Institute for High Temperatures (Russian Federation); Vasiliev, A. I., E-mail: vasiliev@npo.lit.ru; Kostyuchenko, S. V.; Sokolov, D. V.; Startsev, A. Yu. [Joint Stock Company NPO LIT (Russian Federation); Kudryavtsev, N. N. [Moscow Institute of Physics and Technology (State University) (Russian Federation)

2011-12-15T23:59:59.000Z

209

Optical voltage reference  

DOE Patents (OSTI)

An optical voltage reference for providing an alternative to a battery source. 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.

Rankin, R.; Kotter, D.

1992-12-31T23:59:59.000Z

210

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

211

Active filters for high-voltage direct-current (HVDC) converter terminals: Final report  

SciTech Connect

This report evaluates the technical and economic feasibility for active filtering of dc-side voltage harmonics and the ac-side current harmonics produced by a HVDC converter. The following designs for the active filter concepts are compared with the existing ac-side and dc-side passive filters used at the Dickinson terminal of the CU HVDC transmission line project: the dc-side active filter consisting of a capacitor coupled current injection source to actively ''neutralize'' the 12th, 24th and the 36th harmonics and, the ac-side active filter designed to provide the same fundamental frequency reactive VARs as the existing passive filters. Controlled currents are injected to actively filter the 11th and the 13th harmonic currents. A cost comparison is made between these active filter designs and existing passive filters supplied by the United Power Association (UPA). 22 figs., 11 tabs.

Mohan, N.; Wong, C.

1988-08-01T23:59:59.000Z

212

SF6 dielectric behavior in a high voltage circuit breaker at low temperature under lightning impulses  

Science Conference Proceedings (OSTI)

This work concerns the study of the dielectric and thermodynamic behavior of SF{sub 6} in a 145 kV circuit breaker subjected to lightning impulse voltages in both polarities at temperatures varying from ambient (20 C) to {minus}45 C. The filling of the circuit breaker with SF{sub 6} is carried out at the reference point: T = 15 C, P = 6 bars abs. and d = 39.6 kg/m{sup 3}. Devices allowing to detect the appearance of local condensation of SF{sub 6} and to identify the breakdown between the circuit-breaker contacts and the flashover outside the circuit-breaker, are presented. The experimental results show a general tendency to a decrease in the U{sub 50%} voltage when the temperature is decreased at constant density (a decrease by about 5% when the temperature was decreased from +20 C to {minus}25 C). Such a variation would not have a significant influence in industrial practice. Even if this variation is very weak, it also appears from the obtained results that the gas density is not the only parameter which has an influence on the electric strength of the gas. However, to compare results at different temperatures, it would be better to make it at constant density and not at constant pressure, to avoid the dependency of the ratio (E/N) on N (where E is the electric strength and N the density). On the other hand, it seems that the presence of the liquid in the circuit breaker is not a penalizing parameter. The distribution of the electric field corresponding to the geometrical configuration of the studied circuit-breaker is also presented.

Buret, F.; Beroual, A. [Ecole Centrale de Lyon, Ecully (France)

1996-01-01T23:59:59.000Z

213

Charge Lifetime Study of K2CsSb Photocathode Inside a JLAB DC High Voltage Gun  

SciTech Connect

Two photocathodes are frequently considered for generating high average current electron beams and/or beams with high brightness for current and future accelerator applications: GaAs:Cs and K2CsSb. Each photocathode has advantages and disadvantages, and need to demonstrate performance at 'production' accelerator facilities. To this end a K2CsSb photocathode was manufactured at Brookhaven National Lab and delivered to Jefferson Lab within a compact vacuum apparatus at pressure {approx} 5 x 10{sup -11} Torr. This photocathode was installed inside a dc high voltage photogun biased at voltages up to 200 kV, and illuminated with laser light at 440 or 532 nm, to generate beams up to 20 mA. Photocathode charge lifetime measurements indicate that under some conditions this cathode has exceptionally high charge lifetime, without measurable QE decay, even from the center of the photocathode where operation using GaAs photocathodes is precluded due to ion bombardment. These studies also suggest a complex QE decay mechanism likely related to chemistry and localized heating via the laser beam.

Mammei, R.; Rao, T.; Suleiman, R.; Poelker, M.; Smedley, J.; McCarter, J.L.

2011-10-01T23:59:59.000Z

214

Stability of high. beta. large aspect ratio tokamaks  

SciTech Connect

High {beta}({beta}{much gt} {epsilon}/q{sup 2}) large aspect ratio ({epsilon} {much gt} 1) tokamak equilibria are shown to be always stable to ideal M.H.D. modes that are localized about a flux surface. Both the ballooning and interchange modes are shown to be stable. This work uses the analytic high {beta} large aspect ratio tokamak equilibria developed by Cowley et.al., which are valid for arbitrary pressure and safety factor profiles. The stability results make no assumption about these profiles or the shape of the boundary. 14 refs., 4 figs.

Cowley, S.C.

1991-10-01T23:59:59.000Z

215

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

Science Conference Proceedings (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

216

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

Science Conference Proceedings (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

217

Analysis of system wide distortion in an integrated power system utilizing a high voltage DC bus and silicon carbide power devices  

E-Print Network (OSTI)

This research investigates the distortion on the electrical distribution system for a high voltage DC Integrated Power System (IPS). The analysis was concentrated on the power supplied to a propulsion motor driven by an ...

Fallier, William F. (William Frederick)

2007-01-01T23:59:59.000Z

218

Analog Integrated Circuits and Signal Processing, 42, 231238, 2005 c ? 2005 Springer Science + Business Media, Inc. Manufactured in The Netherlands. Cascode Monolithic DC-DC Converter for Reliable Operation at High Input Voltages  

E-Print Network (OSTI)

Abstract. A cascode bridge circuit for monolithic switching DC-DC converters operating at high input voltages is proposed in this paper. The proposed circuit can also be used as an I/O buffer to interface circuits operating at significantly different voltages. The circuit technique permits the full integration of the active and passive devices of a switching DC-DC converter with a high voltage conversion ratio in a standard low voltage CMOS technology. The cascode bridge structure guarantees the reliable operation of deep submicrometer MOSFETs without exposure to high voltage stress while operating at high input and output voltages. With the proposed circuit technique, steady-state voltage differences between the terminals of all of the MOSFETs in a switching DC-DC converter are maintained within a range imposed by a target low voltage CMOS technology. High-to-low DC-DC converters operating at input voltages up to three times as high as the maximum voltage that can be directly applied across the terminals of a MOSFET are described. An efficiency of 79.6 % is achieved for 5.4 volts to 0.9 volts conversion assuming a 0.18 m CMOS technology. The DC-DC converter operates at a switching frequency of 97 MHz while supplying a DC current of 250 mA to the load. Key Words: low voltage DC-DC converters, monolithic voltage regulators, low voltage CMOS technology, MOSFET reliability issues, high voltage stress 1.

Volkan Kursun; Siva G. Narendra; Vivek K. De; Eby G. Friedman

2004-01-01T23:59:59.000Z

219

Improved Off-State Stress Critical Voltage on AlGaN/GaN High Electron Mobility Transistors Utilizing Pt/Ti/Au Based Gate Metallization  

Science Conference Proceedings (OSTI)

The critical voltage for degradation of AlGaN/GaN high electron mobility transistors (HEMTs) employed with the Pt/Ti/Au gate metallization instead of the commonly used Ni/Au was significantly increased during the off-state stress. The typical critical voltage for HEMTs with Ni/Au gate metallization was around -60V. By sharp contrast, no critical voltage was observed for the HEMTs with Pt/Ti/Au gate metallization, even up to -100V, which was the instrumental limitation in this experiment. Both Schottky forward and reverse gate characteristics of the Ni/Au degraded once the gate voltage passed the critical voltage of around -60V. There was no degradation exhibited for the HEMTs with Pt-gated HEMTs.

Lo, C. F. [University of Florida; Liu, L. [University of Florida, Gainesville; Kang, Tsung Sheng [University of Florida, Gainesville; Davies, Ryan [University of Florida; Gila, Brent P. [University of Florida, Gainesville; Pearton, S. J. [University of Florida; Kravchenko, Ivan I [ORNL; Laboutin, O. [Kopin Corporation, Taunton, MA; Cao, Yu [Kopin Corporation, Taunton, MA; Johnson, Wayne J. [Kopin Corporation, Taunton, MA; Ren, F. [University of Florida

2011-01-01T23:59:59.000Z

220

Differential voltage analyses of high-power lithium-ion cells 4. Cells containing NMC.  

DOE Green Energy (OSTI)

Cells with and without a LiC{sub 2}O{sub 4}BF{sub 2} electrolyte additive and that contained Li{sub 1.05}(Mn{sub 1/3}Co{sub 1/3}Ni{sub 1/3}){sub 0.95}O{sub 2} (NMC) positive electrodes were tested for calendar and cycle life at 60% state of charge. The temperatures used in these tests were 25 and 45 C (cycle life) and 45 and 55 C (calendar life). An analysis of the C/25 capacity data shows that the C/25 capacity decreases with the square root of time. The additive slowed down the rate of capacity decline. The C/25 data were subjected to differential voltage analysis to determine the possible cause of the capacity decrease and at which electrode the capacity decrease was occurring. Data from full cells and half-cells were compared to elucidate individual electrode contributions. This analysis indicated that lithium-capacity-consuming side reactions were occurring primarily at the negative electrode.

Bloom, I.; Walker, L. K.; Basco, J. K.; Abraham, D. P.; Christophersen, J. P.; Ho, C. D.; Chemical Sciences and Engineering Division; INL

2010-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage large" 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

Measuring and tuning energy efficiency on large scale high performance computing platforms.  

Science Conference Proceedings (OSTI)

Recognition of the importance of power in the field of High Performance Computing, whether it be as an obstacle, expense or design consideration, has never been greater and more pervasive. While research has been conducted on many related aspects, there is a stark absence of work focused on large scale High Performance Computing. Part of the reason is the lack of measurement capability currently available on small or large platforms. Typically, research is conducted using coarse methods of measurement such as inserting a power meter between the power source and the platform, or fine grained measurements using custom instrumented boards (with obvious limitations in scale). To collect the measurements necessary to analyze real scientific computing applications at large scale, an in-situ measurement capability must exist on a large scale capability class platform. In response to this challenge, we exploit the unique power measurement capabilities of the Cray XT architecture to gain an understanding of power use and the effects of tuning. We apply these capabilities at the operating system level by deterministically halting cores when idle. At the application level, we gain an understanding of the power requirements of a range of important DOE/NNSA production scientific computing applications running at large scale (thousands of nodes), while simultaneously collecting current and voltage measurements on the hosting nodes. We examine the effects of both CPU and network bandwidth tuning and demonstrate energy savings opportunities of up to 39% with little or no impact on run-time performance. Capturing scale effects in our experimental results was key. Our results provide strong evidence that next generation large-scale platforms should not only approach CPU frequency scaling differently, but could also benefit from the capability to tune other platform components, such as the network, to achieve energy efficient performance.

Laros, James H., III

2011-08-01T23:59:59.000Z

222

Demonstration of Commissioning Tests for Extra-High Voltage Cross-Linked Polyethylene Cable Systems at Los Angeles Department of Wat er and Power  

Science Conference Proceedings (OSTI)

Today, utilities are installing an increasing number of cross-linked polyethylene (XLPE) transmission cables with system voltages ranging from 115 kV up to 345 kV. This report summarizes field partial discharge measurements and high-voltage ac commissioning tests performed on a Los Angeles Department of Water and Power (LADWP) 230-kV XLPE transmission cable system. The commissioning tests were performed with a field transportable, variable frequency, series resonant test set at 1.4 times rated voltage.

2002-09-11T23:59:59.000Z

223

High energy physics - The large and the small  

Science Conference Proceedings (OSTI)

In this Sixth International School on Field Theory and Gravitation, I was invited to give this talk to the students and researchers of Field Theory mainly about LHC - The Large Hadron Collider and results. I will try to summarize the main daily life of the high energy physics and give an idea about the experiments and the expectations for the near future. I will comment the present results and the prospects to LHC/CMS.

Santoro, Alberto [Universidade do Estado do Rio de Janeiro (Brazil)

2012-09-24T23:59:59.000Z

224

Fragmentation of Thin Wires under High Voltage Pulses and Bipolar Fusion  

Science Conference Proceedings (OSTI)

In this article we present an alternative explanation of the phenomenon of wire fragmentation under high transient currents based on classical electromagnetism. We also explain how this phenomenon can be utilized as a primitive example of low energy-high power disruptive phenomena that can affect even nuclear matter.

Papageorgiou, C. D. [Dept. of Electrical and Electronic Engineering, National Technical University of Athens (Greece); Raptis, T. E. [Division of Applied Technologies, National Centre for Science and Research 'Demokritos', Patriarchou Grigoriou and Neapoleos, Athens (Greece)

2010-01-21T23:59:59.000Z

225

Surge voltage suppression in residential power circuits  

Science Conference Proceedings (OSTI)

... Tran- sients in Low Voltage Supply Systems,'' The ... a high-voltage transformer for an oil furnace ... of service entrance SPD of 1960-1970 vintage were ...

2013-05-17T23:59:59.000Z

226

Design issues in low-voltage high-speed current-mode logic buffers  

Science Conference Proceedings (OSTI)

A current-mode logic (CML) buffer is based on a simple differential circuit. This paper investigates important problems involved in the design of a CML buffer as well as a chain of tapered CML buffers. A new design procedure to systematically design ... Keywords: VLSI, current-mode logic, high-speed, integrated circuit, noise

Payam Heydari

2003-04-01T23:59:59.000Z

227

Effect of trapping on the critical voltage for degradation in gan high electron mobility transistors  

E-Print Network (OSTI)

We have performed V[subscript DS] = 0 V and OFF-state step-stress experiments on GaN-on-Si and GaN-on-SiC high electron mobility transistors under UV illumination and in the dark. We have found that for both stress conditions, ...

Demirtas, Sefa

228

H20: New Ceramic-matrix Composite for Low Voltage High Energy ...  

Science Conference Proceedings (OSTI)

C19: Dissolution Behavior of Cu Under Bump Metallization in Ball Grid Array Structure ... E11: Evolution of the Grain Boundary Character Distribution During Grain ... for High Volume and Fast Turnaround Automated Inline TEM Sample Preparation .... H2: Triboluminescent Smart Sensors for Structural Health Monitoring.

229

Analysis and design of a high-current, high-voltage accurate power supply for the APS storage ring  

SciTech Connect

There are 81 dipole magnets contained in the storage ring at the Advanced Photon Source (APS). These magnets are connected in series and are energized by only one 12-phase power supply. The eighty-first magnet is located in a temperature-controlled room with an NMR probe to monitor the magnetic field in the magnet and provide a reference signal for correction of the field drift due to aging of the components. The current in the magnets will be held at 497 A. The required current stability of the power supply is {plus_minus}30 ppM, the current reproducibility is {plus_minus}50 ppM, and the current ripple is {plus_minus}400 ppM. The voltage required to maintain such a current in the magnets is about 1700 V. Different schemes for regulating current in the magnets are studied. Pspice software is used to simulate the behavior and the design of such a power supply under different conditions. The pros and cons of each scheme will be given and the proper power and regulating scheme will be selected.

Fathizadeh, M.

1993-08-01T23:59:59.000Z

230

Thermalization in collisions of large nuclei at high energies  

E-Print Network (OSTI)

Hydrodynamical analysis of experimental data of ultrarelativistic heavy ion collisions seems to indicate that the hot QCD matter created in the collisions thermalizes very quickly. Theoretically, we have no idea why this should be true. In this proceeding, I will describe how the thermalization takes place in the most theoretically clean limit -- that of large nuclei at asymptotically high energy per nucleon, where the system is described by weak-coupling QCD. In this limit, plasma instabilities dominate the dynamics from immediately after the collision until well after the plasma becomes nearly in equilibrium at time t \\alpha^(-5/2)Q^(-1).

Kurkela, Aleksi

2013-01-01T23:59:59.000Z

231

High Performance Multivariate Visual Data Exploration for Extremely Large Data  

SciTech Connect

One of the central challenges in modern science is the need to quickly derive knowledge and understanding from large, complex collections of data. We present a new approach that deals with this challenge by combining and extending techniques from high performance visual data analysis and scientific data management. This approach is demonstrated within the context of gaining insight from complex, time-varying datasets produced by a laser wakefield accelerator simulation. Our approach leverages histogram-based parallel coordinates for both visual information display as well as a vehicle for guiding a data mining operation. Data extraction and subsetting are implemented with state-of-the-art index/query technology. This approach, while applied here to accelerator science, is generally applicable to a broad set of science applications, and is implemented in a production-quality visual data analysis infrastructure. We conduct a detailed performance analysis and demonstrate good scalability on a distributed memory Cray XT4 system.

Rubel, Oliver; Wu, Kesheng; Childs, Hank; Meredith, Jeremy; Geddes, Cameron G.R.; Cormier-Michel, Estelle; Ahern, Sean; Weber, Gunther H.; Messmer, Peter; Hagen, Hans; Hamann, Bernd; Bethel, E. Wes; Prabhat,

2008-08-22T23:59:59.000Z

232

? Adjustable Output Voltage  

E-Print Network (OSTI)

The LM25010 features all the functions needed to implement a low cost, efficient, buck regulator capable of supplying in excess of 1A load current. This high voltage regulator integrates an N-Channel Buck Switch, and is available in thermally enhanced LLP-10 and TSSOP-14EP packages. The constant on-time regulation scheme requires no loop compensation resulting in fast load transient response and simplified circuit implementation. The operating frequency remains constant with line and load variations due to the inverse relationship between the input voltage and the on-time. The valley current limit detection is set at 1.25A. Additional features include: VCC under-voltage lock-out, thermal shutdown, gate drive under-voltage lock-out, and maximum duty cycle limiter.

Lmq Is Aec-q Grade

2008-01-01T23:59:59.000Z

233

HIGH VOLTAGE ELECTRODES  

DOE Patents (OSTI)

S>This patent relates to electrode structure for creating an intense direct current electric field which may have a field strength of the order of two to three times that heretofore obtained, with automatic suppression of arcing. The positive electrode is a conventional conductive material such as copper while the negative electrode is made from a special material having a resistivity greater than that of good conductors and less than that of good insulators. When an incipient arc occurs, the moderate resistivity of the negative electrode causes a momentary, localized decrease in the electric field intensity, thus suppressing the flow of electrons and avoiding arcing. Heated glass may be utilized for the negative electrode, since it provides the desired combination of resistivity, capacity, dielectric strength, mechani-cal strength, and thermal stability. (AEC)

Murray, J.J.

1963-04-23T23:59:59.000Z

234

An in depth examination of semi floating gate ultra low voltage flip-flops for high speed applications.  

E-Print Network (OSTI)

??In this thesis 4 different ultra low voltage (ULV) flip-flops are presented. Floating gates has been exploited to significantly increase the drain-source current. This technique (more)

Simenstad, Erik Jonathan

2013-01-01T23:59:59.000Z

235

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

E-Print Network (OSTI)

The profound digitization of modern microelectronic modules made Analog-to- Digital converters (ADC) key components in many systems. With resolutions up to 14bits and sampling rates in the 100s of MHz, the pipeline ADC is a prime candidate for a wide range of applications such as instrumentation, communications and consumer electronics. However, while past work focused on enhancing the performance of the pipeline ADC from an architectural standpoint, little has been done to individually address its fundamental building blocks. This work aims to achieve the latter by proposing design techniques to improve the performance of these blocks with minimal power consumption in low voltage environments, such that collectively high performance is achieved in the pipeline ADC. Towards this goal, a Recycling Folded Cascode (RFC) amplifier is proposed as an enhancement to the general performance of the conventional folded cascode. Tested in Taiwan Semiconductor Manufacturing Company (TSMC) 0.18?m Complementary Metal Oxide Semiconductor (CMOS) technology, the RFC provides twice the bandwidth, 8-10dB additional gain, more than twice the slew rate and improved noise performance over the conventional folded cascode-all at no additional power or silicon area. The direct auto-zeroing offset cancellation scheme is optimized for low voltage environments using a dual level common mode feedback (CMFB) circuit, and amplifier differential offsets up to 50mV are effectively cancelled. Together with the RFC, the dual level CMFB was used to implement a sample and hold amplifier driving a singleended load of 1.4pF and using only 2.6mA; at 200MS/s better than 9bit linearity is achieved. Finally a power conscious technique is proposed to reduce the kickback noise of dynamic comparators without resorting to the use of pre-amplifiers. When all techniques are collectively used to implement a 1Vpp 10bit 160MS/s pipeline ADC in Semiconductor Manufacturing International Corporation (SMIC) 0.18[mu]m CMOS, 9.2 effective number of bits (ENOB) is achieved with a near Nyquist-rate full scale signal. The ADC uses an area of 1.1mm2 and consumes 42mW in its analog core. Compared to recent state-of-the-art implementations in the 100-200MS/s range, the presented pipeline ADC uses the least power per conversion rated at 0.45pJ/conversion-step.

Assaad, Rida Shawky

2009-12-01T23:59:59.000Z

236

Large Scale Computing and Storage Requirements for High Energy Physics  

E-Print Network (OSTI)

Director Editors Richard Gerber Harvey Wasserman NERSC UserServices Group NERSC User Services Group Large ScaleNERSC

Gerber, Richard A.

2011-01-01T23:59:59.000Z

237

High-Order Terms in the Asymptotic Expansions of the Steady-State Voltage Potentials in the Presence of Conductivity Inhomogeneities of Small Diameter  

E-Print Network (OSTI)

We derive high-order terms in the asymptotic expansions of the steady-state voltage potentials in the presence of a finite number of diametrically small inhomogeneities with conductivities different from the background conductivity. Our derivation is rigorous, and based on layer potential techniques. The asymptotic expansions in this paper are valid for inhomogeneities with Lipschitz boundaries and those with extreme conductivities.

Habib Ammari; Hyeonbae Kang

2001-12-12T23:59:59.000Z

238

Low-voltage gyrotrons  

SciTech Connect

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

239

Large Scale Computing and Storage Requirements for High Energy Physics  

E-Print Network (OSTI)

Computing and Storage Requirements for High Energy Physics [for High Energy Physics Computational and Storage for High Energy Physics Computational and Storage

Gerber, Richard A.

2011-01-01T23:59:59.000Z

240

Large Scale Computing and Storage Requirements for High Energy Physics  

E-Print Network (OSTI)

the application of high performance computing (HPC) to theacceleration and high performance computing. He was thelibraries, and high performance computing. Lee is an active

Gerber, Richard A.

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage large" 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

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

Science Conference Proceedings (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

242

Large Scale Computing and Storage Requirements for High Energy Physics  

Science Conference Proceedings (OSTI)

The National Energy Research Scientific Computing Center (NERSC) is the leading scientific computing facility for the Department of Energy's Office of Science, providing high-performance computing (HPC) resources to more than 3,000 researchers working on about 400 projects. NERSC provides large-scale computing resources and, crucially, the support and expertise needed for scientists to make effective use of them. In November 2009, NERSC, DOE's Office of Advanced Scientific Computing Research (ASCR), and DOE's Office of High Energy Physics (HEP) held a workshop to characterize the HPC resources needed at NERSC to support HEP research through the next three to five years. The effort is part of NERSC's legacy of anticipating users needs and deploying resources to meet those demands. The workshop revealed several key points, in addition to achieving its goal of collecting and characterizing computing requirements. The chief findings: (1) Science teams need access to a significant increase in computational resources to meet their research goals; (2) Research teams need to be able to read, write, transfer, store online, archive, analyze, and share huge volumes of data; (3) Science teams need guidance and support to implement their codes on future architectures; and (4) Projects need predictable, rapid turnaround of their computational jobs to meet mission-critical time constraints. This report expands upon these key points and includes others. It also presents a number of case studies as representative of the research conducted within HEP. Workshop participants were asked to codify their requirements in this case study format, summarizing their science goals, methods of solution, current and three-to-five year computing requirements, and software and support needs. Participants were also asked to describe their strategy for computing in the highly parallel, multi-core environment that is expected to dominate HPC architectures over the next few years. The report includes a section that describes efforts already underway or planned at NERSC that address requirements collected at the workshop. NERSC has many initiatives in progress that address key workshop findings and are aligned with NERSC's strategic plans.

Gerber, Richard A.; Wasserman, Harvey

2010-11-24T23:59:59.000Z

243

Experimental and theoretical studies of a high temperature cesium-barium tacitron, with application to low voltage-high current inversion. Final report, April 1, 1993--February 28, 1994  

SciTech Connect

A low voltage/high current switch refer-red as ``Cs-Ba tacitron`` is studied for use as a dc to ac inverter in high temperature and/or ionizing radiation environments. The operational characteristics of the Cs-Ba tacitron as a switch were investigated experimentally in three modes: (a) breakdown mode, (b) I-V mode, and (c) current modulation mode. Operation parameters measured include switching frequencies up to 20 kHz, hold-off voltages up to 200 V, current densities in excess of 15 A/CM{sup 2}, switch power density of 1 kW/cm{sup 2}, and a switching efficiency in excess of 90 % at collector voltages greater than 30 V. Also, if the discharge current is circuit limited to a value below the maximum thermal emission current density, the voltage drop is constant and below 3 V.

Murray, C.S.; El-Genk, M.S.

1994-02-01T23:59:59.000Z

244

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

245

HIGH VOLTAGE TERMINAL IN COSY ELECTRON COOLER V.A. Chekavinskiy, E.A. Bekhtenev, I.A. Gusev, M.N. Kondaurov, V.R. Kozak, E.A. Kuper, V.R.  

E-Print Network (OSTI)

, and powered by multistage transformer, capable of 15 kW power at 26 kHz. Wireless control is passed through high voltage circumstances. Powering of HVT electronics is provided by cascade transformer acceleration system ­ high voltage terminal. All power and control electronics were placed in a single isolated

Kozak, Victor R.

246

Large Scale Computing and Storage Requirements for High Energy Physics  

NLE Websites -- All DOE Office Websites (Extended Search)

for High Energy Physics for High Energy Physics Accelerator Physics P. Spentzouris, Fermilab Motivation Accelerators enable many important applications, both in basic research and applied sciences Different machine attributes are emphasized for different applications * Different particle beams and operation principles * Different energies and intensities Accelerator science and technology objectives for all applications * Achieve higher energy and intensity, faster and cheaper machine design, more reliable operation a wide spectrum of requirements for very complex instruments. Assisting their design and operation requires an equally complex set of computational tools. High Energy Physics Priorities High energy frontier * Use high-energy colliders to discover new particles and

247

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

DOE Green Energy (OSTI)

This work reports the surface stability of the high voltage Li ion cathode LiMn{sub 2x}Ni{sub x}O{sub 4?} (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 PF{sub 6} to POF{sub 3} 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.; Yang, Ming-Che; Veith, G. M.; Dudney, N. J.; Meng, Ying Shirley

2012-01-01T23:59:59.000Z

248

Voltage balanced multilevel voltage source converter system  

SciTech Connect

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

249

Voltage balanced multilevel voltage source converter system  

SciTech Connect

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

250

Decision support system for estimating the technically and economically exploitable renewable energy sources potential in wide areas for connection to high voltage networks  

Science Conference Proceedings (OSTI)

A decision support information system for estimating the technically and economically exploitable renewable energy sources (RES) potential in wide areas is presented in this paper. The system estimates the RES potential in specific areas, examines ... Keywords: DSS, GIS, biomass, decision support systeoms, distributed generation, geographical information systems, high voltage network, renewable energy estimation, renewable energy forecasting, renewable energy potential, renewable energy sources, small hydro, wind energy, wind power

Michael Psalidas; Demosthenes Agoris; Vassilis Kilias; Kostas Tigas; Panagiotis Stratis; Giannis Vlachos

2005-04-01T23:59:59.000Z

251

Feasibility Study for the Development of High-Voltage, Low-Current Power Semiconductor Devices: 2003 Strategic Science and Technolog y Project  

Science Conference Proceedings (OSTI)

The intelligent universal transformer (IUT) will be an advanced power-electronics replacement for conventional distribution transformers that adds significant new functional capabilities to those available from conventional copper and iron transformers. This report assesses the state of the art and development options for obtaining high-voltage, low-current power semiconductors (both switches and diodes) needed in the circuit topology being developed for the IUT.

2004-03-29T23:59:59.000Z

252

Impact of High-Penetration PV on Distribution System Performance: Assessment of Regulation Control Options for Voltage Mitigation  

Science Conference Proceedings (OSTI)

Photovoltaics are beginning to challenge distribution system power engineers nationwide. The impact photovoltaics (PV) has on the power system is directly tied to system characteristics which include but are not limited to voltage class, load, regulation, and short circuit capacity. In addition to the system characteristics, the solar characteristics also play a key role. These include details on the PV systems themselves in addition to the solar irradiance data. The correlation of PV output and ...

2012-12-31T23:59:59.000Z

253

New Class of High Strength Nanostructured Steel for Large Scale ...  

Science Conference Proceedings (OSTI)

... from automotive and aerospace applications to power tools and household ... Consolidation of Blended Magnesium and Ceramic Powders by Microwave Heating ... High Energy Ball Milling of A356 Aluminium Casting Alloy Machining Chips.

254

High-Throughput Dry Processes for Large-Area Devices  

DOE Green Energy (OSTI)

In October 1996, an interdisciplinary team began a three-year LDRD project to study the plasma processes of reactive ion etching and plasma-enhanced chemical vapor deposition on large-area silicon devices. The goal was to develop numerical models that could be used in a variety of applications for surface cleaning, selective etching, and thin-film deposition. Silicon solar cells were chosen as the experimental vehicle for this project because an innovative device design was identified that would benefit from immediate performance improvement using a combination of plasma etching and deposition processes. This report presents a summary of the technical accomplishments and conclusions of the team.

BUSS,RICHARD J.; HEBNER,GREGORY A.; RUBY,DOUGLAS S.; YANG,PIN

1999-11-01T23:59:59.000Z

255

Characterization of a commercially available large area, high detection efficiency single-photon avalanche diode  

E-Print Network (OSTI)

We characterize a new commercial, back-illuminated reach-through silicon single-photon avalanche photo diode (SPAD) SAP500 (Laser Components. Inc.), operated in Geiger-mode for purpose of photon counting. We show that for this sensor a significant interplay exists between dark counts, detection efficiency, afterpulsing, excess voltage and operating temperature, sometimes requiring a careful optimization tailored for a specific application. We find that a large flat plateau of sensitive area of about 0.5 mm in diameter, a peak quantum efficiency of 73% at 560 nm and timing precision down to 150 ps FWHM are the main distinguishing characteristics of this SPAD.

Stip?evi?, Mario; Ursin, Rupert

2013-01-01T23:59:59.000Z

256

Cell Voltage Noise Reduction Based on Wavelet in Aluminum ...  

Science Conference Proceedings (OSTI)

Presentation Title, Cell Voltage Noise Reduction Based on Wavelet in Aluminum ... cell voltage signals collected in aluminium electrolysis process are with high...

257

Dynamic Simulation of Cell Voltage Resonance Effect in Aluminum ...  

Science Conference Proceedings (OSTI)

Dubal Cell Voltage Drop Initiatives towards Low Energy High Amperage Cells Dynamic Simulation of Cell Voltage Resonance Effect in Aluminum Electrolysis...

258

High voltage research (breakdown strengths of gaseous and liquid insulators). Semiannual report, April 1--September 30, 1977  

DOE Green Energy (OSTI)

Direct current breakdown strength measurements on a large number of multicomponent gas mixtures at low (approximately less than 1 atm) and high (approximately less than 5 atm) pressures led to the discovery of many gas mixtures of electron-attaching gases and strongly electron-attaching gases with N/sub 2/ and C/sub 3/F/sub 8/ which are superior to SF/sub 6/. Of special significance are mixtures containing C/sub 4/F/sub 6/ (perfluoro-2-butyne). The breakdown strength of one such mixture (20 percent C/sub 4/F/sub 6/ to 80 percent SF/sub 6/) is approximately 30 percent higher than pure SF/sub 6/ under identical conditions, both at low (approximately 0.7 atm) and high (4.6 atm) pressures. Perfluorocyclohexene (C/sub 6/F/sub 10/) and C/sub 5/F/sub 8/ (perfluorocyclopentene) were found at low pressure (approximately 0.2 atm) to be, respectively, approximately 2.1 and 2.2 times better than SF/sub 6/ under comparable conditions; they both have a potential as additives in gas mixtures. The effect of the inelastic electron scattering properties of a gas via negative ion resonances in the low-energy range (1 to approximately 4 eV) on the breakdown strength has been demonstrated for H/sub 2/, N/sub 2/, and CO and binary mixtures of these with SF/sub 6/ and C/sub 4/F/sub 6/ (perfluoro-2-butyne). The construction of a new high pressure (to approximately 11 atm), variable temperature (-50/sup 0/C to + 150/sup 0/C) apparatus has been completed and a practical test facility utilizing cylindrical electrode geometries has been put into operation; the first results on the latter apparatus were on SF/sub 6/-N/sub 2/ and c-C/sub 4/F/sub 8/--N/sub 2/ mixtures. Studies of environmental effects of dielectric gases via their electron-impact-induced decompositions and analysis of their breakdown products have begun using mass spectrometry and gas chromatography; C/sub 4/F/sub 6/ (perfluoro-2-butyne) seems to be resistant to electron-impact-induced decomposition indicating long-term stability.

Christophorou, L. G.; James, D. R.; Pai, R. Y.; Mathis, R. A.; Pace, M. O.; Bouldin, D. W.; Christodoulides, A. A.; Chan, C. C.

1977-11-01T23:59:59.000Z

259

PQ Encyclopedia: Understanding Voltage Unbalance  

Science Conference Proceedings (OSTI)

This PQ Encyclopedia examines voltage unbalance, methods to calculate line voltages and the degree of voltage unbalance, and mitigation techniques.

2009-12-11T23:59:59.000Z

260

Low voltage ride-through capability improvement of wind power generation using dynamic voltage restorer  

Science Conference Proceedings (OSTI)

Recently, the total amount of generation from wind power plants has been increased all over the world. In this situation, a large amount of disconnection of wind generation may give a serious influence in the power system. Consequently, Low Voltage Ride-Through ... Keywords: dynamic voltage restorer, energy storage, fault ride-through, fixed-speed induction generator, low voltage ride-through, voltage sag, wind power generation

Naohiro Hasegawa; Teruhisa Kumano

2010-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage large" 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

Remote visualization of large scale data for ultra-high resolution display environments  

Science Conference Proceedings (OSTI)

ParaView is one of the most widely used scientific tools that support parallel visualization of large scale data. The Scalable Adaptive Graphics Environment (SAGE) is a graphics middleware that enables real-time streaming of ultra-high resolution visual ... Keywords: ParaView, SAGE, large-scale data, remote visualization, ultra-high resolution visualization

Sungwon Nam; Byungil Jeong; Luc Renambot; Andrew Johnson; Kelly Gaither; Jason Leigh

2009-11-01T23:59:59.000Z

262

Enhancing Open Circuit Voltage by Combining Thermoelectric ...  

Science Conference Proceedings (OSTI)

Enhancing Open Circuit Voltage by Combining Thermoelectric Materials and Dye -Sensitized Solar Cell in Series Estimation of Compressive Strength of High...

263

Mitigation of different type voltage sags in low voltage distribution systems using dynamic voltage restorer  

Science Conference Proceedings (OSTI)

The main problems of the voltage sag in low voltage distribution systems due to sensitive loads. Voltage sags can caused malfunction in the distribution system. In order to protect voltage sags in the network a device which called Dynamic Voltage Restorer ... Keywords: custom device, dynamic voltage restorer (DVR), low voltage, power injected, voltage sag

Rosli Omar

2010-03-01T23:59:59.000Z

264

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

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

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

265

Large Plastic Deformation in High-Capacity Lithium-Ion Batteries Caused by Charge and Discharge  

E-Print Network (OSTI)

Large Plastic Deformation in High-Capacity Lithium-Ion Batteries Caused by Charge and Discharge, Massachusetts 02138 Evidence has accumulated recently that a high-capacity elec- trode of a lithium-ion battery in the particle is high, possibly leading to fracture and cavitation. I. Introduction LITHIUM-ION batteries

Suo, Zhigang

266

Virtually distortion-free imaging system for large field, high resolution lithography  

DOE Patents (OSTI)

Virtually distortion free large field high resolution imaging is performed using an imaging system which contains large field distortion or field curvature. A reticle is imaged in one direction through the optical system to form an encoded mask. The encoded mask is then imaged back through the imaging system onto a wafer positioned at the reticle position.

Hawryluk, Andrew M. (Modesto, CA); Ceglio, Natale M. (Livermore, CA)

1993-01-01T23:59:59.000Z

267

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

268

Induced-charge electrokinetics at large voltages  

E-Print Network (OSTI)

The classical transport theory cannot explain the experimental behavior of electrochemical systems in the extreme operating conditions required by modern microfluidics devices. Some experimental puzzles include strange ...

Kilic, Mustafa Sabri

2008-01-01T23:59:59.000Z

269

Constant voltage ultracapacitor  

Science Conference Proceedings (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

Ezzat G. Bakhoum

2012-01-01T23:59:59.000Z

270

The correlation of the electrical properties with electron irradiation and constant voltage stress for MIS devices based on high-k double layer (HfTiSiO: N and HfTiO:N) dielectrics  

Science Conference Proceedings (OSTI)

This paper describes the influence of e-beam irradiation and constant voltage stress on the electrical characteristics of metal-insulator-semiconductor structures, with double layer high-k dielectric stacks containing HfTiSiO:N and HfTiO:N ultra-thin ... Keywords: Electrical properties, High-k dielectrics, Metal-insulator-semiconductor (MIS) devices

V. Mikhelashvili; P. Thangadurai; W. D. Kaplan; G. Eisenstein

2010-11-01T23:59:59.000Z

271

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

Science Conference Proceedings (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

272

Temperature Fitting Method Predicting Equidistant Voltage Drop of ...  

Science Conference Proceedings (OSTI)

High Temperature Compression Test to Determine the Anode Paste ... Temperature Fitting Method Predicting Equidistant Voltage Drop of Anode Nod in ...

273

Automated Voltage Control in LHCb  

E-Print Network (OSTI)

LHCb is one of the 4 LHC experiments. In order to ensure the safety of the detector and to maximize efficiency, LHCb needs to coordinate its own operations, in particular the voltage configuration of the different subdetectors, according to the accelerator status. A control software has been developed for this purpose, based on the Finite State Machine toolkit and the SCADA system used for control throughout LHCb (and the other LHC experiments). This software permits to efficiently drive both the Low Voltage (LV) and High Voltage (HV) systems of the 10 different sub-detectors that constitute LHCb, setting each sub-system to the required voltage (easily configurable at run-time) based on the accelerator state. The control software is also responsible for monitoring the state of the Sub-detector voltages and adding it to the event data in the form of status-bits. Safe and yet flexible operation of the LHCb detector has been obtained and automatic actions, triggered by the state changes of the ...

Granado Cardoso, L; Jacobsson, R

2011-01-01T23:59:59.000Z

274

Substation voltage upgrading  

SciTech Connect

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

275

The Use of Large Transparent Ceramics in a High Powered, Diode Pumped Solid State Laser  

SciTech Connect

The advent of large transparent ceramics is one of the key enabling technological advances that have shown that the development of very high average power compact solid state lasers is achievable. Large ceramic neodymium doped yttrium aluminum garnet (Nd:YAG) amplifier slabs are used in Lawrence Livermore National Laboratory's (LLNL) Solid State Heat Capacity Laser (SSHCL), which has achieved world record average output powers in excess of 67 kilowatts. We will describe the attributes of using large transparent ceramics, our present system architecture and corresponding performance; as well as describe our near term future plans.

Yamamoto, R; Bhachu, B; Cutter, K; Fochs, S; Letts, S; Parks, C; Rotter, M; Soules, T

2007-09-24T23:59:59.000Z

276

Ultra high energy cosmic rays and the large scale structure of the galactic magnetic field  

E-Print Network (OSTI)

We study the deflection of ultra high energy cosmic ray protons in different models of the regular galactic magnetic field. Such particles have gyroradii well in excess of 1 kpc and their propagation in the galaxy reflects only the large scale structure of the galactic magnetic field. A future large experimental statistics of cosmic rays of energy above 10$^{19}$ eV could be used for a study of the large scale structure of the galactic magnetic field if such cosmic rays are indeed charged nuclei accelerated at powerful astrophysical objects and if the distribution of their sources is not fully isotropic.

Todor Stanev

1996-07-17T23:59:59.000Z

277

A 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 picoampers 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, G.M.

1990-12-21T23:59:59.000Z

278

Incorporating Voltage Fluctuations of the Power Distribution Network into the Transient Analysis of CMOS Logic Gates  

Science Conference Proceedings (OSTI)

Decreased power supply levels have reduced the tolerance to voltage changes within power distribution networks in CMOS integrated circuits. High on-chip currents, required to charge and discharge large on-chip loads while operating at high frequencies, ... Keywords: IR drops, power distribution network, system-on-a-chip

Kevin T. Tang; Eby G. Friedman

2002-05-01T23:59:59.000Z

279

High-Voltage Impulse Testers  

Science Conference Proceedings (OSTI)

... The objective of this test circuit is to super- impose on a ... pulse is coupled across inductance L by the coupling capacitor Ca. ... P lastic Capacitors, Inc. ...

2013-05-17T23:59:59.000Z

280

Automated Voltage Standard Ready  

Science Conference Proceedings (OSTI)

... We wanted a standard that was ... as envisioned, then within our lifetimes there will no longer be a need for voltage transfer standards that have to be ...

2013-04-08T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage large" 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.


281

Study of highly-excited string states at the Large Hadron Collider  

E-Print Network (OSTI)

In TeV-scale gravity scenarios with large extra dimensions, black holes may be produced at future colliders. Good arguments have been made for why general relativistic black holes may be just out of reach of the Large Hadron Collider (LHC). However, in weakly-coupled string theory, highly excited string states - string balls - could be produced at the LHC with high rates and decay thermally, not unlike general relativistic black holes. In this paper, we simulate and study string ball production and decay at the LHC. We specifically emphasize the experimentally-detectable similarities and differences between string balls and general relativistic black holes at a TeV scale.

Douglas M. Gingrich; Kevin Martell

2008-08-19T23:59:59.000Z

282

Effect of high-energy neutral particles on extreme ultraviolet spectroscopy in large helical device  

Science Conference Proceedings (OSTI)

Spectra measured by an extreme ultraviolet (EUV) spectrometer frequently suffer large spike noise when Large Helical Device is operated in low-density range ({order to examine the effect of NBI, a carbon filter with thickness of 150 nm was installed in the EUV spectrometer. As a result, the spike noise was reduced by an order of magnitude. It is experimentally verified that the spike noise is caused by escaping high-energy neutral particles resulting from the circulating high-energy hydrogen ions borne from NBI.

Dong Chunfeng; Sakaue, Hiroyuki [National Institute for Fusion Science, Toki 509-5292, Gifu (Japan); Morita, Shigeru; Tokitani, Masayuki; Goto, Motoshi [National Institute for Fusion Science, Toki 509-5292, Gifu (Japan); Department of Fusion Science, Graduate University for Advanced Studies, Toki 509-5292, Gifu (Japan); Wang, Erhui [Department of Fusion Science, Graduate University for Advanced Studies, Toki 509-5292, Gifu (Japan); Zushi, Hideki [RIAM, Kyushu University, Kasuga 816-8580, Fukuoka (Japan)

2012-10-15T23:59:59.000Z

283

High Temperature, Large Sample Volume, Constant Flow Magic Angle Spinning NMR Probe for a 11  

NLE Websites -- All DOE Office Websites (Extended Search)

High Temperature, Large Sample Volume, Constant Flow Magic Angle Spinning NMR Probe for a High Temperature, Large Sample Volume, Constant Flow Magic Angle Spinning NMR Probe for a 11.7 T Magnetic Field for In Situ Catalytic Reaction Characterization Project start date: April 1, 2007 EMSL Lead Investigator: Joseph Ford, EMSL High Field Magnetic Resonance Facility Co-investigators: Jian Zhi Hu, Macromolecular Structure and Dynamics, Biological Science Division, FCSD Jesse Sears and David W. Hoyt, EMSL High Field Magnetic Resonance Facility Detailed understanding of the mechanisms involved in a catalytic reaction requires identification of the nature of the active sites and the temporal evolution of reaction intermediates. Although optical methods such as UV-visible and infrared (IR) spectroscopies can be used for some types of reactions, these do not

284

LARGE-SCALE HYDROGEN PRODUCTION FROM NUCLEAR ENERGY USING HIGH TEMPERATURE ELECTROLYSIS  

DOE Green Energy (OSTI)

Hydrogen can be produced from water splitting with relatively high efficiency using high-temperature electrolysis. This technology makes use of solid-oxide cells, running in the electrolysis mode to produce hydrogen from steam, while consuming electricity and high-temperature process heat. When coupled to an advanced high temperature nuclear reactor, the overall thermal-to-hydrogen efficiency for high-temperature electrolysis can be as high as 50%, which is about double the overall efficiency of conventional low-temperature electrolysis. Current large-scale hydrogen production is based almost exclusively on steam reforming of methane, a method that consumes a precious fossil fuel while emitting carbon dioxide to the atmosphere. Demand for hydrogen is increasing rapidly for refining of increasingly low-grade petroleum resources, such as the Athabasca oil sands and for ammonia-based fertilizer production. Large quantities of hydrogen are also required for carbon-efficient conversion of biomass to liquid fuels. With supplemental nuclear hydrogen, almost all of the carbon in the biomass can be converted to liquid fuels in a nearly carbon-neutral fashion. Ultimately, hydrogen may be employed as a direct transportation fuel in a hydrogen economy. The large quantity of hydrogen that would be required for this concept should be produced without consuming fossil fuels or emitting greenhouse gases. An overview of the high-temperature electrolysis technology will be presented, including basic theory, modeling, and experimental activities. Modeling activities include both computational fluid dynamics and large-scale systems analysis. We have also demonstrated high-temperature electrolysis in our laboratory at the 15 kW scale, achieving a hydrogen production rate in excess of 5500 L/hr.

James E. O'Brien

2010-08-01T23:59:59.000Z

285

Large area, high spatial resolution tracker for new generation of high luminosity experiments in Hall A at Jefferson Lab  

Science Conference Proceedings (OSTI)

In 2014 the CEBAF electron accelerator at Jefferson Lab (JLab) will deliver a longitudinally polarized (up to 85%), high intensity (up to 100 ?A) beam with maximum energy of 12 GeV, twice the present value. To exploit the new opportunities that the energy upgrade will offer, a new spectrometer (Super BigBite - SBS) is under development, featuring very forward angle, large acceptance and ability to operate in high luminosity environment. The tracking system of SBS will consist of large area (40150 cm2 and 50200 cm2), high spatial resolution (better than 100 ?m) chambers based on the GEM technology and 2 small (1020 cm) Silicon Strip Detector planes. The design of the GEM chambers and its sub-components such as the readout electronics is resented here.

Bellini, V; Castelluccio, D; Colilli, S; Cisbani, E; De Leo, R; Fratoni, R; Frullani, S; Garibaldi, F; Guiliani, F; Guisa, A; Gricia, M; Lucentini, M; Meddi, F; Minutoli, S; Musico, P; Noto, F; De Oliveira, R; Santavenere, F; Sutera, M C

2011-06-01T23:59:59.000Z

286

Distant Freehand Pointing and Clicking on Very Large, High Resolution Displays  

E-Print Network (OSTI)

Distant Freehand Pointing and Clicking on Very Large, High Resolution Displays Daniel Vogel, Ravin" selection with finger or thumb. ABSTRACT We explore the design space of freehand pointing and clicking interfaces. Although alternatives like gesture-based interfaces have been explored, the self-revealing nature

Toronto, University of

287

Free Boundary, High Beta Equilibrium in a Large Aspect Ratio Tokamak with Nearly  

E-Print Network (OSTI)

Free Boundary, High Beta Equilibrium in a Large Aspect Ratio Tokamak with Nearly Circular Plasma Boundary H. Qin A. Reiman September 25, 1996 Abstract An analytic solution is obtained for free. In the absence of surface currents at the plasma-vacuum in- terface, the free-boundary equilibrium solution

288

Free Boundary, High Beta Equilibrium in a Large Aspect Ratio Tokamak with Nearly  

E-Print Network (OSTI)

Free Boundary, High Beta Equilibrium in a Large Aspect Ratio Tokamak with Nearly Circular Plasma Boundary H. Qin A. Reiman September 25, 1996 Abstract An analytic solution is obtained for free. In the absence of surface currents at the plasma­vacuum in­ terface, the free­boundary equilibrium solution

289

Charge trapping in ultrathin Gd2O3 high-k dielectric  

Science Conference Proceedings (OSTI)

Charge trapping in ultrathin high-k Gd"2O"3 dielectric leading to appearance of hysteresis in C-V curves is studied by capacitance-voltage and current-voltage techniques. It was shown that the large leakage current at a negative gate voltage causes the ... Keywords: Charge trapping, Gd2O3, High-k dielectric, Rare earth oxide

A. N. Nazarov; Y. V. Gomeniuk; Y. Y. Gomeniuk; H. D. B. Gottlob; M. Schmidt; M. C. Lemme; M. Czernohorsky; H. J. Osten

2007-09-01T23:59:59.000Z

290

Recent progress in large grain/single crystal high RRR niobium  

DOE Green Energy (OSTI)

High RRR bulk niobium Superconducting Radio Frequency (SRF) cavity technology is chosen for the International Linear Collider (ILC). The SRF community was convinced until now that fine grain polycrystalline RRR niobium sheets obtained via forging and cross rolling are essential for forming the SRF Cavities. However, it was recently discovered under a joint Reference Metals Company, Inc., - JLAB CRADA that large grain/single crystal RRR niobium sliced directly from ingots is highly ductile reaching 100 percent elongation. This discovery led to the successful fabrication of several SRF single and/or multi cell structures, formed with sliced RRR discs from the ingots, operating at 2.3, 1.5 and 1.3 GHz. This new exciting development is expected to offer high performance accelerator structures not only at reduced costs but also with simpler fabrication and processing conditions. As a result there is a renewed interest in the evaluation and understanding of the large grain and single crystal niobium with respect to their mechanical & physical properties as well as the oxidation behavior and the influence of impurities such as hydrogen and Ta. In this paper the results of many collaborative studies on large grain and single crystal high RRR niobium between JLAB, Universities and Industry are presented.

Ganapati Rao Myneni; Peter Kneisel; Tadeu Carneiro; S.R. Agnew; F. Stevie

2005-11-07T23:59:59.000Z

291

Reactive Power Management to Address Short-Term Voltage Stability Using Optimal Reactive Power Allocation Method  

Science Conference Proceedings (OSTI)

Voltage stability has attracted attention recently because power systems are increasingly operated under heavy loads and subjected to high levels of dynamic fast acting loads. Voltage instability under these conditions can be manifested as depressed voltage profiles, delayed voltage recovery at load buses following a major disturbance, and even fast voltage collapse. Single-phase, low-inertia induction motors can have adverse effect on voltage stability as they decelerate in the event of voltage ...

2012-11-28T23:59:59.000Z

292

Substation voltage upgrading  

SciTech Connect

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

293

Voltage Quality Improvement Using DVR  

Science Conference Proceedings (OSTI)

The problem of voltage sags and Swells and its severe impact on sensitive loads is well known. To solve this problem, custom power devices are used. One of those devices is the Dynamic Voltage Restorer (DVR), which is one of the most efficient and effective ... Keywords: Dynamic Voltage Restorer (DVR), Voltage sags, Voltage swells, Custom power, Power Quality

M. Arun Bhaskar; S. S. Dash; C. Subramani; M. Jagadeesh Kumar; P. R. Giresh; M. Varun Kumar

2010-03-01T23:59:59.000Z

294

Parametric Study Of Large-Scale Production Of Syngas Via High Temperature Co-Electrolysis  

DOE Green Energy (OSTI)

A process model has been developed to evaluate the potential performance of a largescale high-temperature co-electrolysis plant for the production of syngas from steam and carbon dioxide. The co-electrolysis process allows for direct electrochemical reduction of the steam carbon dioxide gas mixture, yielding hydrogen and carbon monoxide, or syngas. The process model has been developed using the Honeywell UniSim systems analysis code. Using this code, a detailed process flow sheet has been defined that includes all the components that would be present in an actual plant such as pumps, compressors, heat exchangers, turbines, and the electrolyzer. Since the electrolyzer is not a standard UniSim component, a custom one-dimensional co-electrolysis model was developed for incorporation into the overall UniSim process flow sheet. The one dimensional co-electrolysis model assumes local chemical equilibrium among the four process-gas species via the gas shift reaction. The electrolyzer model allows for the determination of co-electrolysis outlet temperature, composition (anode and cathode sides); mean Nernst potential, operating voltage and electrolyzer power based on specified inlet gas flow rates, heat loss or gain, current density, and cell area-specific resistance. The one-dimensional electrolyzer model was validated by comparison with results obtained from a fully three dimensional computational fluid dynamics model developed using FLUENT, and by comparison to experimental data. This paper provides representative results obtained from the UniSim flow sheet model for a 300 MW co-electrolysis plant, coupled to a high-temperature gas-cooled nuclear reactor. The coelectrolysis process, coupled to a nuclear reactor, provides a means of recycling carbon dioxide back into a useful liquid fuel. If the carbon dioxide source is based on biomass, the overall process, from production through utilization, would be climate neutral.

J. E. O'Brien; M. G. McKellar; C. M. Stoots; J. S. Herring; G. L. Hawkes

2007-11-01T23:59:59.000Z

295

Large High Resolution Displays for Co-Located Collaborative Sensemaking: Display Usage and Territoriality  

SciTech Connect

Large, high-resolution vertical displays carry the potential to increase the accuracy of collaborative sensemaking, given correctly designed visual analytics tools. From an exploratory user study using a fictional textual intelligence analysis task, we investigated how users interact with the display to construct spatial schemas and externalize information, as well as how they establish shared and private territories. We investigated the space management strategies of users partitioned by type of tool philosophy followed (visualization- or text-centric). We classified the types of territorial behavior exhibited in terms of how the users interacted with information on the display (integrated or independent workspaces). Next, we examined how territorial behavior impacted the common ground between the pairs of users. Finally, we offer design suggestions for building future co-located collaborative visual analytics tools specifically for use on large, high-resolution vertical displays.

Bradel, Lauren; Endert, Alexander; Koch, Kristen; Andrews, Christopher; North, Chris

2013-08-01T23:59:59.000Z

296

Operating Water Cherenkov Detectors in high altitude sites for the Large Aperture GRB Observatory  

E-Print Network (OSTI)

Water Cherenkov Detectors (WCD) are efficient detectors for detecting GRBs in the 10 GeV - 1 TeV energy range using the single particle technique, given their sensitivity to low energy secondary photons produced by high energy photons when cascading in the atmosphere. The Large Aperture GRB Observatory (LAGO) operates arrays of WCD in high altitude sites (above 4500 m a.s.l.) in Bolivia, Mexico and Venezuela, with planned extension to Peru. Details on the operation and stability of these WCD in remote sites with high background rates of particles will be detailed, and compared to simulations. Specific issues due to operation at high altitude, atmospheric effects and solar activity, as well as possible hardware enhancements will also be presented.

Allard, D; Asorey, H; Barros, H; Bertou, X; Castillo, M; Chirinos, J M; De Castro, A; Flores, S; Gonzlez, J; Berisso, M Gomez; Grajales, J; Guada, C; Day, W R Guevara; Ishitsuka, J; Lpez, J A; Martnez, O; Melfo, A; Meza, E; Loza, P Miranda; Barbosa, E Moreno; Murrugarra, C; Nez, L A; Ormachea, L J Otiniano; Prez, G; Perez, Y; Ponce, E; Quispe, J; Quintero, C; Rivera, H; Rosales, M; Rovero, A C; Saavedra, O; Salazar, H; Tello, J C; Peralda, R Ticona; Varela, E; Velarde, A; Villaseor, L; Wahl, D; Zamalloa, M A

2009-01-01T23:59:59.000Z

297

Distributed Generation Source Stiffness and Its Impact on Voltage Distortion  

Science Conference Proceedings (OSTI)

Distributed generators with loads that create high harmonics can cause excessive voltage distortion. This report's objective was to evaluate under controlled laboratory conditions voltage distortion resulting from application of nonlinear load for three different types of rotary generators and one inverter-based generator. Test results also were used to verify the analytical model for predicting voltage distortion from nonlinear load application.

2001-11-27T23:59:59.000Z

298

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

SciTech Connect

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

299

Device for monitoring cell voltage  

SciTech Connect

A device for monitoring a rechargeable battery having a number of electrically connected cells includes at least one current interruption switch for interrupting current flowing through at least one associated cell and a plurality of monitoring units for detecting cell voltage. Each monitoring unit is associated with a single cell and includes a reference voltage unit for producing a defined reference threshold voltage and a voltage comparison unit for comparing the reference threshold voltage with a partial cell voltage of the associated cell. The reference voltage unit is electrically supplied from the cell voltage of the associated cell. The voltage comparison unit is coupled to the at least one current interruption switch for interrupting the current of at least the current flowing through the associated cell, with a defined minimum difference between the reference threshold voltage and the partial cell voltage.

Doepke, Matthias (Garbsen, DE); Eisermann, Henning (Edermissen, DE)

2012-08-21T23:59:59.000Z

300

Cryogenic loading of large volume presses for high-pressure experimentation and synthesis of novel materials  

Science Conference Proceedings (OSTI)

We present an efficient easily implemented method for loading cryogenic fluids in a large volume press. We specifically apply this method to the high-pressure synthesis of an extended solid derived from CO using a Paris-Edinburgh cell. This method employs cryogenic cooling of Bridgman type WC anvils well insulated from other press components, condensation of the load gas within a brass annulus surrounding the gasket between the Bridgman anvils. We demonstrate the viability of the described approach by synthesizing macroscopic amounts (several milligrams) of polymeric CO-derived material, which were recovered to ambient conditions after compression of pure CO to 5 GPa or above.

Lipp, M J; Evans, W J; Yoo, C S

2005-01-21T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage large" 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

Electron launching voltage monitor  

DOE Patents (OSTI)

An electron launching voltage monitor measures MITL voltage using a relationship between anode electric field and electron current launched from a cathode-mounted perturbation. An electron launching probe extends through and is spaced from the edge of an opening in a first MITL conductor, one end of the launching probe being in the gap between the MITL conductor, the other end being adjacent a first side of the first conductor away from the second conductor. A housing surrounds the launching probe and electrically connects the first side of the first conductor to the other end of the launching probe. A detector detects the current passing through the housing to the launching probe, the detected current being representative of the voltage between the conductors.

Mendel, Clifford W. (Albuquerque, NM); Savage, Mark E. (Albuquerque, NM)

1992-01-01T23:59:59.000Z

302

Voltage Stability/Security Assessment and On-Line Control: Volumes 1-4  

Science Conference Proceedings (OSTI)

To address growing utility concerns of voltage instability and possible voltage collapse, EPRI has developed a new voltage stability analysis package for large power systems, VSTAB. This off-line planning tool provides information on a utility power system's proximity to and mechanism of voltage instability.

1993-05-01T23:59:59.000Z

303

P.: Quick simulation methods for estimating the unreliability of regenerative models of large highly reliable systems  

E-Print Network (OSTI)

We investigate fast simulation techniques for estimating the unreliability in large Markovian models of highly reliable systems for which analytical0numerical techniques are difficult to apply+ We first show mathematically that for small time horizons, the relative simulation error, when using the importance sampling techniques of failure biasing and forcing, remains bounded as component failure rates tend to zero+ This is in contrast to naive simulation where the relative error tends to infinity+ For large time horizons where these techniques are not efficient, we use the approach of first bounding the unreliability in terms of regenerative-cycle-based measures and then estimating the regenerative-cycle-based measures using importance sampling; the latter can be done very efficiently+ We first use bounds developed in the literature for the asymptotic distribution of the time to hitting a rare set in regenerative systems+ However, these bounds are close to the unreliability only for a certain range of time horizons+ We develop new bounds that make use of the special structure of the systems that we consider and are close to the unreliability for a much wider range of time horizons+ These techniques extend to non-Markovian, highly reliable systems as long as the regenerative structure is preserved+ 2004 Cambridge University Press 0269-9648004 $16+00 339340 M. K. Nakayama and P. Shahabuddin 1.

Marvin K. Nakayama; Perwez Shahabuddin

2004-01-01T23:59:59.000Z

304

Development of Large High-Voltage PV Modules with Improved Reliability and Lower Cost: Final Subcontract Report, 1 April 2006--31 August 2007  

DOE Green Energy (OSTI)

The overall objective was to provide NREL with technical results that enhance its capability to improve PV manufacturing technology by developing a PV module with specified characteristics.

Wohlgemuth, J.

2009-05-01T23:59:59.000Z

305

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

306

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

307

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

308

The Current-voltage Characteristics of Grain Boundaries in Ionic ...  

Science Conference Proceedings (OSTI)

Presentation Title, The Current-voltage Characteristics of Grain Boundaries in Ionic ... A High-temperature Mssbauer Study of Iron-doped Ruddlesden-popper ...

309

Voltage Controlled Creep of a Nanoporous Gold/Electrolyte Hybrid ...  

Science Conference Proceedings (OSTI)

And the creep rate can also be controlled by the voltage (electrochemical ... CNT Reinforced Copper Composite for High Contact Pressure Electrodes by...

310

Patents and Perspective on Surge Protection for Low-Voltage ...  

Science Conference Proceedings (OSTI)

... In a high-voitage inverter the impedance is a resistor functioning to dampen voltage o\\ershoots and to im- plement a relay or solid state second ...

2013-05-17T23:59:59.000Z

311

Demonstration of High Efficiency Elastocaloric Cooling with Large Delta- T Using NiTi Wires  

Science Conference Proceedings (OSTI)

Vapor compression (VC) is by far the most dominant technology for meeting all cooling and refrigeration needs around the world. It is a mature technology with the efficiency of modern compressors approaching the theoretical limit, but its envi-ronmental footprint remains a global problem. VC refrigerants such as hydrochlo-roflurocarbons (HCFCs) and hydrofluorocarbons (HFCs) are a significant source of green house gas (GHG) emissions, and their global warming potential (GWP) is as high as 1000 times that of CO2. It is expected that building space cooling and re-frigeration alone will amount to {approx} 5% of primary energy consumption and {approx}5% of all CO2 emission in U.S. in 2030 . As such, there is an urgent need to develop an al-ternative high-efficiency cooling technology that is affordable and environmentally friendly. Among the proposed candidates, magnetocaloric cooling (MC) is currently received a lot of attention because of its high efficiency. However, MC is inherently expensive because of the requirement of large magnetic field and rare earth materi-als. Here, we demonstrate an entirely new type of solid-state cooling mechanism based on the latent heat of reversible martensitic transformation. We call it elasto-caloric cooling (EC) after the superelastic transformation of austenite it utilizes. The solid-state refrigerant of EC is cost-effective, and it completely eliminates the use of any refrigerants including HCFCs/HFCs. We show that the COP (coefficient of per-formance) of a jugular EC with optimized materials can be as high as > 10 with measured {Delta}T of 17 C.

Cui, Jun; Wu, Yiming; Muehlbauer, Jan; Hwang, Yunho; Radermacher, Reinhard; Fackler, Sean; Wuttig, Manfred; Takeuchi, Ichiro

2012-08-01T23:59:59.000Z

312

Automatic voltage-imbalance detector  

DOE Patents (OSTI)

A device is described 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, R.E.; McCormick, J.B.; Kerwin, W.J.

1981-05-20T23:59:59.000Z

313

ANTARES proposal: Towards a large scale high energy cosmic neutrino undersea detector  

E-Print Network (OSTI)

The ANTARES collaboration propose to observe High Energy Cosmic Neutrinos using a Deep Sea Cherenkov detector. The sky survey with high energy neutrinos is complementary to the observations with photons. It is expected that this will shed a new light on the understanding of the origin of cosmics rays, on galactic and extra galactic sources. In this document, we will elaborate on the potential interest of such a study for Astrophysicists and Particle Physicists. For Oceanologists participating in the collaboration, the main goal is a long term measurement of environmental parameters in the deep sea. We propose to explore the possibility of a km-scale detector to be installed in a deep site in the Mediterranean sea, for which a broad collaboration will be needed. A variety of technical problems have to be solved. Strong constraints coming from the deep sea environment and the lack of accessibility, require sea science engineering expertise. For items such as detector deployment in deep water, data transmission through optical cables, corrosion, bio-fouling of optical modules, positioning, we have found technical support from collaborators and partners which have experience in this field (COM, CSTN, CTME, IFREMER, France Telecom Cables, INSU-CNRS...). We will test the sea engineering part of a detector including test deployments close to the Toulon coast (France) where technical support is available and where several sites at depths down to 2500 m are easily accessible. During the same time, issues connected to the accomplishment of a large scale detector and the selection of an optimum site will be addressed. We propose to build and install a demonstrator (a fully equipped 3-dimensional test array) the design of which can be extended to a km^3 scale detector. We plan to reach this goal within the next 2 years.

ANTARES collaboration

1997-07-11T23:59:59.000Z

314

Original article: Selective compensation of voltage harmonics in grid-connected microgrids  

Science Conference Proceedings (OSTI)

In this paper, a novel approach is proposed for selective compensation of main voltage harmonics in a grid-connected microgrid. The aim of compensation is to provide a high voltage quality at the point of common coupling (PCC). PCC voltage quality is ... Keywords: Distributed generator (DG), Grid-connected, Microgrid, Voltage harmonics compensation

Mehdi Savaghebi, Juan C. Vasquez, Alireza Jalilian, Josep M. Guerrero, Tzung-Lin Lee

2013-05-01T23:59:59.000Z

315

Novel Large Area High Resolution Neutron Detector for the Spallation Neutron Source  

Science Conference Proceedings (OSTI)

Neutron scattering is a powerful technique that is critically important for materials science and structural biology applications. The knowledge gained from past developments has resulted in far-reaching advances in engineering, pharmaceutical and biotechnology industries, to name a few. New facilities for neutron generation at much higher flux, such as the SNS at Oak Ridge, TN, will greatly enhance the capabilities of neutron scattering, with benefits that extend to many fields and include, for example, development of improved drug therapies and materials that are stronger, longer-lasting, and more impact-resistant. In order to fully realize this enhanced potential, however, higher neutron rates must be met with improved detection capabilities, particularly higher count rate capability in large size detectors, while maintaining practicality. We have developed a neutron detector with the technical and economic advantages to accomplish this goal. This new detector has a large sensitive area, offers 3D spatial resolution, high sensitivity and high count rate capability, and it is economical and practical to produce. The proposed detector technology is based on B-10 thin film conversion of neutrons in long straw-like gas detectors. A stack of many such detectors, each 1 meter in length, and 4 mm in diameter, has a stopping power that exceeds that of He-3 gas, contained at practical pressures within an area detector. With simple electronic readout methods, straw detector arrays can provide spatial resolution of 4 mm FWHM or better, and since an array detector of such form consists of several thousand individual elements per square meter, count rates in a 1 m^2 detector can reach 2?10^7 cps. Moreover, each individual event can be timetagged with a time resolution of less than 0.1 ?sec, allowing accurate identification of neutron energy by time of flight. Considering basic elemental cost, this novel neutron imaging detector can be commercially produced economically, probably at a small fraction of the cost of He-3 detectors. In addition to neutron scattering science, the fully developed base technology can be used as a rugged, low-cost neutron detector in area monitoring and surveying. Radiation monitors are used in a number of other settings for occupational and environmental radiation safety. Such a detector can also be used in environmental monitoring and remote nuclear power plant monitoring. For example, the Department of Energy could use it to characterize nuclear waste dumps, coordinate clean-up efforts, and assess the radioactive contaminants in the air and water. Radiation monitors can be used to monitor the age and component breakdown of nuclear warheads and to distinguish between weapons and reactor grade plutonium. The UN's International Atomic Energy Agency (IAEA) uses radiation monitors for treaty verification, remote monitoring, and enforcing the non-proliferation of nuclear weapons. As part of treaty verification, monitors can be used to certify the contents of containers during inspections. They could be used for portal monitoring to secure border checkpoints, sea ports, air cargo centers, public parks, sporting venues, and key government buildings. Currently, only 2% of all sea cargo shipped is inspected for radiation sources. In addition, merely the presence of radiation is detected and nothing is known about the radioactive source until further testing. The utilization of radiation monitors with neutron sensitivity and capability of operation in hostile port environments would increase the capacity and effectiveness of the radioactive scanning processes.

Lacy, Jeffrey L

2009-05-22T23:59:59.000Z

316

An active-optic x-ray fluorescence analyzer with high energy resolution, large solid angle coverage, and a large tuning range  

SciTech Connect

A crystal-optic x-ray fluorescence energy analyzer has been designed and tested, which combines the features of electron-volt energy resolution, large solid angle coverage, and tunability over several kilo-electron-volts. The design is based upon the principle of active optics, with ten actuators available to optimally adjust the shape of a silicon crystal used in the Bragg geometry. In most applications the shape is that of a logarithmic spiral for high energy resolution with a spatially nonresolving detector, but a wide range of other shapes is also possible for applications such as imaging or single-shot spectroscopy in a spectral range of the operator's choosing.

Adams, Bernhard W.; Attenkofer, Klaus [Argonne National Laboratory, Argonne, Illinois 60439 (United States)

2008-02-15T23:59:59.000Z

317

The Constant Voltage Transformer (CVT) for Mitigating Effects of Voltage Sags on Industrial Equipment  

E-Print Network (OSTI)

Electric quality problems associated with power interactions between distribution and industrial process control systems can be prevented. Surveys of large users that buy power at the transmission and distribution voltages turn up relatively few complaints about the quality of their incoming power, while surveys of small users connected at secondary voltages tum up numerous complaints about the quality of their incoming power. Three major changes in the characteristics of customer loads and power distribution systems have altered the nature of the power quality equation: (I) greater sensitivity of devices and equipment to electric power variations, (2) the interconnection of sensitive loads in extensive networks and automated processes, and (3) an increase in loads that use power electronics in some type of power conversion configuration [1][2]. This paper presents applications of the constant-voltage transformer (CVT) for mitigating the effects of electric service voltage sags on industrial equipment in an oil refinery. Unlike conventional transformers, the CVT or ferro-resonant transformer allows the core to become saturated with magnetic flux, which maintains a relatively constant output voltage during input voltage variations such as undervoltages, overvoltages, and harmonic distortion.

Ferraro, R. J.; Osborne, R.; Stephens, R.

2000-04-01T23:59:59.000Z

318

Sequential circuit design for radiation hardened multiple voltage integrated circuits  

DOE Patents (OSTI)

The present invention includes a radiation hardened sequential circuit, such as a bistable circuit, flip-flop or other suitable design that presents substantial immunity to ionizing radiation while simultaneously maintaining a low operating voltage. In one embodiment, the circuit includes a plurality of logic elements that operate on relatively low voltage, and a master and slave latches each having storage elements that operate on a relatively high voltage.

Clark, Lawrence T. (Phoenix, AZ); McIver, III, John K. (Albuquerque, NM)

2009-11-24T23:59:59.000Z

319

High speed, very large (8 megabyte) first in/first out buffer memory (FIFO)  

DOE Patents (OSTI)

A fast FIFO (First In First Out) memory buffer capable of storing data at rates of 100 megabytes per second. The invention includes a data packer which concatenates small bit data words into large bit data words, a memory array having individual data storage addresses adapted to store the large bit data words, a data unpacker into which large bit data words from the array can be read and reconstructed into small bit data words, and a controller to control and keep track of the individual data storage addresses in the memory array into which data from the packer is being written and data to the unpacker is being read.

Baumbaugh, Alan E. (Batavia, IL); Knickerbocker, Kelly L. (Aurora, IL)

1989-01-01T23:59:59.000Z

320

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

Note: This page contains sample records for the topic "high voltage large" 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

Cell Broadening Revisited: Results from High-Resolution Large-Eddy Simulations of Cold Air Outbreaks  

Science Conference Proceedings (OSTI)

Large-eddy simulations (LES) have been carried out in order to investigate the structure and development of organized mesoscale cellular convection (MCC) during cold air outbreaks (CAOB) and to reevaluate results by Mller and Chlond. Some ...

M. Schrter; S. Raasch; H. Jansen

2005-06-01T23:59:59.000Z

322

Chromatin Signature Reveals over a Thousand Highly Conserved Large Non-Coding Rnas in Mammals  

E-Print Network (OSTI)

There is growing recognition that mammalian cells produce many thousands of large intergenic transcripts [1, 2, 3, 4]. However, the functional significance of these transcripts has been particularly controversial. Although ...

Guttman, Mitchell

323

Large-area fabrication of high aspect ratio tantalum photonic crystals for high-temperature selective emitters  

E-Print Network (OSTI)

The authors present highly selective emitters based on two-dimensional tantalum (Ta) photonic crystals, fabricated on 2 in. polycrystalline Ta substrates, for high-temperature applications, e.g., thermophotovoltaic energy ...

Rinnerbauer, Veronika

324

Virtually distortion-free imaging system for large field, high resolution lithography using electrons, ions or other particle beams  

DOE Patents (OSTI)

Virtually distortion free large field high resolution imaging is performed using an imaging system which contains large field distortion or field curvature. A reticle is imaged in one direction through the optical system to form an encoded mask. The encoded mask is then imaged back through the imaging system onto a wafer positioned at the reticle position. Particle beams, including electrons, ions and neutral particles, may be used as well as electromagnetic radiation.

Hawryluk, Andrew M. (Modesto, CA); Ceglio, Natale M. (Livermore, CA)

1993-01-01T23:59:59.000Z

325

Virtually distortion-free imaging system for large field, high resolution lithography using electrons, ions or other particle beams  

DOE Patents (OSTI)

Virtually distortion free large field high resolution imaging is performed using an imaging system which contains large field distortion or field curvature. A reticle is imaged in one direction through the optical system to form an encoded mask. The encoded mask is then imaged back through the imaging system onto a wafer positioned at the reticle position. Particle beams, including electrons, ions and neutral particles, may be used as well as electromagnetic radiation.

Hawryluk, A.M.; Ceglio, N.M.

1991-04-10T23:59:59.000Z

326

Electrochemical and rate performance study of high-voltage lithium-richcomposition: Li1.2Mn0.525Ni0.175Co0.1O2  

Science Conference Proceedings (OSTI)

We report electrochemical studies of high voltage cathodes composed of lithium rich layeredlayered material having the nominal composition Li1.2Mn0.525Ni0.175Co0.1O2, or equivalently 0.6Li[Li1/3Mn2/3]O2 0.4Li[Mn0.3Ni0.45Co0.25]O2. These aspects were investigated by cyclic voltammetry studies in conjunction with electrochemical impedance spectroscopy measurements to understand the redox reactions involving multiple transition metals and their capacity contribution at higher voltages, up to 4.9 V. Further, cathodes with 1.5 wt.% carbon nanofibers added to the Li1.2Mn0.525Ni0.175Co0.1O2 composite electrode showed stable reversible capacities of about 280 mAh g 1 when cycled to 4.9 V for more than 100 cycles, and almost a factor of two improvements in the rate performance compared to the electrode composition prepared using conventional composition (7.5% carbon black and 7.5% binder).

Martha, Surendra K [ORNL; Nanda, Jagjit [ORNL; Veith, Gabriel M [ORNL; Dudney, Nancy J [ORNL

2012-01-01T23:59:59.000Z

327

Humidity, Temperature, and Voltage (Presentation)  

SciTech Connect

An update is given on the work of the PV Quality Assurance Task Force; Group 3: studying the effects of humidity, temperature, and voltage bias.

Wohlgemuth, J.

2012-03-01T23:59:59.000Z

328

Voltage Vehicles | Open Energy Information  

Open Energy Info (EERE)

Sector Vehicles Product Voltage Vehicles is a nascent, full-service alternative fuel vehicle distributor specializing in the full spectrum of electric vehicles (EV) and...

329

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

330

Poster: Towards Highly Accurate Large-Scale Ab Initio Calculations Using Fragment Molecular Method in GAMESS  

Science Conference Proceedings (OSTI)

One of the major challenges of modern quantum chemistry (QC) is to apply it to large systems with thousands of correlated electrons and basis functions. The availability of supercomputers and development of novel methods are necessary to realize this ... Keywords: applications

Maricris L. Mayes, Graham D. Fletcher, Mark S. Gordon

2012-11-01T23:59:59.000Z

331

Large-Eddy Simulation of Flow over Two-Dimensional Obstacles: High Drag States and Mixing  

Science Conference Proceedings (OSTI)

A three-dimensional large-eddy simulation (LES) model was used to examine how stratified flow interacts with bottom obstacles in the coastal ocean. Bottom terrain representing a 2D ridge was modeled using a finite-volume approach with ridge ...

Eric D. Skyllingstad; Hemantha W. Wijesekera

2004-01-01T23:59:59.000Z

332

High resolution mass spectrometry method and system for analysis of whole proteins and other large molecules  

DOE Patents (OSTI)

A matrix assisted laser desorption/ionization (MALDI) method and related system for analyzing high molecular weight analytes includes the steps of providing at least one matrix-containing particle inside an ion trap, wherein at least one high molecular weight analyte molecule is provided within the matrix-containing particle, and MALDI on the high molecular weight particle while within the ion trap. A laser power used for ionization is sufficient to completely vaporize the particle and form at least one high molecular weight analyte ion, but is low enough to avoid fragmenting the high molecular weight analyte ion. The high molecular weight analyte ion is extracted out from the ion trap, and is then analyzed using a detector. The detector is preferably a pyrolyzing and ionizing detector.

Reilly, Peter T. A. (Knoxville, TN); Harris, William A. (Naperville, IL)

2010-03-02T23:59:59.000Z

333

Research on high efficiency, large-area CuInSe{sub 2}-based thin-film modules. Annual subcontract report, 1 May 1991--30 April 1992  

DOE Green Energy (OSTI)

Objective was to demonstrate 12.5% aperture efficient, large area (3900 cm{sup 2}) encapsulated thin thin CuInSe{sub 2} (CIS) modules. The module design consists of 53 series-connected ZnO/CdS/CIS/Mo/glass cells fabricated on a glass substrate. A baseline characterization of the CIS modules was established during Phase 1. Maps of open circuit voltage provide information on junction quality uniformity. Maps of cell voltages at fixed forward bias show variations in resistance losses due to interconnects. Individual cell I-V curves can be evaluated. Physical nature of defects is correlated using OBIC, EBIC, SEM, tape adhesion, etc. A new world record of 37.7 W and 9.7% aperture efficiency was attained for an encapsulated module; an unencapsulated CIS module plate achieved 40.8 W and 10.5% aperture efficiency.

Mitchell, K.W.; Eberspacher, C. [Siemens Solar Industries, Camarillo, CA (United States)

1993-02-01T23:59:59.000Z

334

Measuring and tuning energy efficiency on large scale high performance computing platforms.  

E-Print Network (OSTI)

??Recognition of the importance of power in the field of High Performance Computing, whether it be as an obstacle, expense or design consideration, has never (more)

Laros, James Howard III

2012-01-01T23:59:59.000Z

335

High Throughput Pretreatment and Enzyme Hydrolysis of Biomass: Screening Recalcitrance in Large Sample Populations (Presentation)  

DOE Green Energy (OSTI)

Presentation on the execution of the first high-throughput thermochemical pretreatment/enzyme digestion pipeline for screening biomass for recalcitrance.

Decker, S. R.

2010-10-01T23:59:59.000Z

336

Strain-optic voltage monitor  

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, J.D.

1995-12-31T23:59:59.000Z

337

Researchers at the National Renewable Energy Laboratory (NREL) develop a high-fidelity large-eddy simulation model  

E-Print Network (OSTI)

than current models. As the market for wind energy grows, wind turbines and wind plants are becoming wind plants, reduce the cost of wind energy, and save wind plant developers millions of dollars in lostResearchers at the National Renewable Energy Laboratory (NREL) develop a high-fidelity large

338

Energy Requirement Analysis of Large-Scale Biogas Project in High-Cold Region of China  

Science Conference Proceedings (OSTI)

The annual mean temperature is very low in high cold region of china. The insulating and heating measures on the basis of the energy requirement analysis of biogas project are needed to ensure the normal running of fermentation process. In this paper, ... Keywords: High-cold, Biogas, Fermentation, Heat

Yinsheng Yang; Lili Wang

2012-01-01T23:59:59.000Z

339

Energy based performance tuning for large scale high performance computing systems  

Science Conference Proceedings (OSTI)

Recognition of the importance of power in the field of High Performance Computing, whether it be as an obstacle, expense or design consideration, has never been greater and more pervasive. In response to this challenge, we exploit the unique power measurement ... Keywords: energy efficiency, frequency scaling, high performance computing (HPC), power

James H. Laros, III; Kevin T. Pedretti; Suzanne M. Kelly; Wei Shu; Courtenay T. Vaughan

2012-03-01T23:59:59.000Z

340

Multilevel converters for large electric drives  

SciTech Connect

Traditional two-level high frequency pulse width modulation (PWM) inverters for motor drives have several problems associated with their high frequency switching which produces common-mode voltage and high voltage change (dV/dt) rates to the motor windings. Multilevel inverters solve these problems because their devices can switch at a much lower frequency. Two different multilevel topologies are identified for use as a converter for electric drives, a cascade inverter with separate dc sources and a back-to-back diode clamped converter. The cascade inverter is a natural fit for large automotive all electric drives because of the high VA ratings possible and because it uses several levels of dc voltage sources which would be available from batteries or fuel cells. The back to back diode damped converter is ideal where a source of ac voltage is available such as a hybrid electric vehicle. Simulation and experimental results show the superiority of these two converters over PWM based drives.

Tolbert, L.M.; Peng, F.Z.

1997-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage large" 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

LOW VOLTAGE 14 Mev NEUTRON SOURCE  

DOE Patents (OSTI)

An apparatus yielding high-energy neutrons at the rate of 10/sup 8/ or more per second by the D,T or D,D reactions is described. The deuterium gas filling is ionized by electrons emitted from a filament, and the resulting ions are focused into a beam and accelerated against a fixed target. The apparatus is built in accordance with the relationship V/sub s/ = A--B log pd, where V/sub s/ is the sparking voltage, p the gas pressure, and d the gap length between the high voltage electrodes. Typical parameters to obtain the high neutron yields are 55 to 80 kv, 0.5 to 7.0 ma beam current, 5 to 12 microns D/sub 2/, and a gap length of 1 centimeter.

Little, R.N. Jr.; Graves, E.R.

1959-09-29T23:59:59.000Z

342

Large Field Erected and Packaged High Temperature Water (HTW) Generators for Coal Firing  

E-Print Network (OSTI)

The purpose of the paper is to disseminate information on the energy savings possible with High Temperature Water (HTW) for heating and industrial process application and to provide information on coal fired HTW generator design and availability.

Boushell, C. C.

1980-01-01T23:59:59.000Z

343

High Energy Large Area Surveys: optically obscured AGN and the history of accretion  

E-Print Network (OSTI)

Hard X-ray, large area surveys are a fundamental complement of ultra-deep, pencil beam surveys in obtaining a more complete coverage of the L-z plane, allowing to find luminous QSO in wide z ranges. Furthermore, results from these surveys can be used to make reliable predictions about the luminosity (and hence the redshift) of the sources in the deep surveys which have optical counterparts too faint to be observed with the present generation of optical telescopes. This allows us to obtain accurate luminosity functions on wide luminosity and redshift intervals.

F. Fiore; the HELLAS2XMM collaboration

2004-06-01T23:59:59.000Z

344

BB5, Nearly Ideal Current-Voltage Characteristics of Schottky Barrier ...  

Science Conference Proceedings (OSTI)

Recently, high-quality GaN free-standing substrates are available by various methods. ... Current-voltage (I-V) characteristics and capacitance-voltage (C-V)...

345

Two terminal line voltage thermostat  

Science Conference Proceedings (OSTI)

A two terminal line voltage thermostat includes a switch which effectively connects line voltage to a heater load. The entire process is controlled by an integrated circuit microcontroller which is powered by a rectified voltage from a transformer secondary connected to a primary which is in series with the heater load. Backup battery power is provided to maintain limited functions of the microcontroller in the event of overall power loss. The microcontroller is programmed to meet the temperature sensing and control requirements specific to a two terminal electric baseboard heating installation. 7 figs.

Stalsberg, K.J.; Ingalls, J.E.; Hoglund, S.R.

1995-10-10T23:59:59.000Z

346

Large-Scale Energy Transformations in the High Latitudes of the Northern Hemisphere  

Science Conference Proceedings (OSTI)

The kinetic energy balance and kinetic energy source are studied for high latitudes north of 55N with twice daily upper air observations during a seven-year period from 1973 to 1979. Energy variables are presented for 5 latitudinal zones from ...

E. C. Kung; S. E. Masters; J. A. M. Corte-Real

1983-05-01T23:59:59.000Z

347

Distributed computation of the knn graph for large high-dimensional point sets  

Science Conference Proceedings (OSTI)

High-dimensional problems arising from robot motion planning, biology, data mining, and geographic information systems often require the computation of k nearest neighbor (knn) graphs. The knn graph of a data set is obtained by connecting each point ... Keywords: Approximate nearest neighbors, Distributed and parallel algorithms, Metric spaces, Nearest neighbors, Range queries, Robotics, knn graphs

Erion Plaku; Lydia E. Kavraki

2007-03-01T23:59:59.000Z

348

High-Efficiency Solar Cells for Large-Scale Electricity Generation  

DOE Green Energy (OSTI)

One strategy for helping the solar industry to grow faster is to use very high efficiency cells under concentrating optics. By using lenses or mirrors to concentrate the light, very small solar cells can be used, reducing the amount of semiconductor material and allowing use of higher efficiency cells, which are now >40% efficient.

Kurtz, S.; Olson, J.; Geisz, J.; Friedman, D.; McMahon, W.; Ptak, A.; Wanlass, M.; Kibbler, A.; Kramer, C.; Bertness, K.; Ward, S.; Duda, A.; Young, M.; Carapella, J.; Steiner, M.

2008-09-26T23:59:59.000Z

349

Modeling of large aperture third harmonic frequency conversion of high power Nd:glass laser systems  

SciTech Connect

To provide high-energy, high-power beams at short wavelengths for inertial-confinement-fusion experiments, we routinely convert the 1.053-{mu}m output of the Nova, Nd:phosphate-glass, laser system to its third-harmonic wavelength. We describe performance and conversion efficiency modeling of the 3 {times} 3 arrays potassium-dihydrogen-phosphate crystal plates used for type II/type II phase-matched harmonic conversion of Nova 0.74-m diameter beams, and an alternate type I/type II phase-matching configuration that improves the third-harmonic conversion efficiency. These arrays provide energy conversion of up to 65% and intensity conversion to 70%. 19 refs., 11 figs.

Henesian, M.A.; Wegner, P.J.; Speck, D.R.; Bibeau, C.; Ehrlich, R.B.; Laumann, C.W.; Lawson, J.K.; Weiland, T.L.

1991-03-13T23:59:59.000Z

350

Chapter 4 - Understanding Voltage Sags  

Science Conference Proceedings (OSTI)

This chapter of the EPRI Solutions PQ Encyclopedia provides information for understanding the voltage sag, which is the single most potent cause of end user power quality (PQ) problems.

2005-12-31T23:59:59.000Z

351

Extending PVSCAN to meet the market needs for high-speed, large-area scanning  

DOE Green Energy (OSTI)

PVSCAN is a versatile instrument that has many applications in the PV industry, including high-speed mapping of material and cell parameters such as defect density, reflectance, and LBIC response. Recently, the PV community has been interested in acquiring this instrument for material and cell analyses and for process monitoring. This paper explores various issues that arise in developing a commercial instrument such as PVSCAN. Emphasis is on the technical details of the ability to scan fast and the detrimental effects this fast scan can have on the image quality of various material/cell parameters.

Sopori, B.; Chen, W.; Zhang, Y.; Hemschoot, T.; Madjdpour, J.

1999-10-26T23:59:59.000Z

352

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.

353

Large Oscillations of the Magnetoresistance in Nanopatterned High-temperature Superconducting Films  

SciTech Connect

Measurements on nanoscale structures constructed from high-temperature superconductors are expected to shed light on the origin of superconductivity in these materials. To date, loops made from these compounds have had sizes of the order of hundreds of nanometeres. Here, we report the results of measurements on loops of La{sub 1.84}Sr{sub 0.16}CuO{sub 4}, a high-temperature superconductor that loses its resistance to electric currents when cooled below {approx}38 K, with dimensions down to tens of nanometres. We observe oscillations in the resistance of the loops as a function of the magnetic flux through the loops. The oscillations have a period of h/2e, and their amplitude is much larger than the amplitude of the resistance oscillations expected from the Little-Parks effect. Moreover, unlike Little-Parks oscillations, which are caused by periodic changes in the superconducting transition temperature, the oscillations we observe are caused by periodic changes in the interaction between thermally excited moving vortices and the oscillating persistent current induced in the loops. However, despite the enhanced amplitude of these oscillations, we have not detected oscillations with a period of h/e, as recently predicted for nanoscale loops of superconductors with d-wave symmetry or with a period of h/4e, as predicted for superconductors that exhibit stripes.

Sochnikov, I.; Bozovic, I.; Shaulov, A.; Yeshurun, Y.; Logvenov, G.

2010-07-01T23:59:59.000Z

354

Local Dynamic Reactive Power for Correction of System Voltage Problems  

SciTech Connect

Distribution systems are experiencing outages due to a phenomenon known as local voltage collapse. Local voltage collapse is occurring in part because modern air conditioner compressor motors are much more susceptible to stalling during a voltage dip than older motors. These motors can stall in less than 3 cycles (.05s) when a fault, such as on the sub-transmission system, causes voltage to sag to 70 to 60%. The reasons for this susceptibility are discussed in the report. During the local voltage collapse, voltages are depressed for a period of perhaps one or two minutes. There is a concern that these local events are interacting together over larger areas and may present a challenge to system reliability. An effective method of preventing local voltage collapse is the use of voltage regulation from Distributed Energy Resources (DER) that can supply or absorb reactive power. DER, when properly controlled, can provide a rapid correction to voltage dips and prevent motor stall. This report discusses the phenomenon and causes of local voltage collapse as well as the control methodology we have developed to counter voltage sag. The problem is growing because of the use of low inertia, high efficiency air conditioner (A/C) compressor motors and because the use of electric A/C is growing in use and becoming a larger percentage of system load. A method for local dynamic voltage regulation is discussed which uses reactive power injection or absorption from local DER. This method is independent, rapid, and will not interfere with conventional utility system voltage control. The results of simulations of this method are provided. The method has also been tested at the ORNL s Distributed Energy Communications and Control (DECC) Laboratory using our research inverter and synchronous condenser. These systems at the DECC Lab are interconnected to an actual distribution system, the ORNL distribution system, which is fed from TVA s 161kV sub-transmission backbone. The test results are also provided and discussed. The simulations and testing show that local voltage control from DER can prevent local voltage collapse. The results also show that the control can be provided so quickly, within 0.5 seconds, that is does not interfere with conventional utility methods.

Kueck, John D [ORNL; Rizy, D Tom [ORNL; Li, Fangxing [ORNL; Xu, Yan [ORNL; Li, Huijuan [University of Tennessee, Knoxville (UTK); Adhikari, Sarina [ORNL; Irminger, Philip [ORNL

2008-12-01T23:59:59.000Z

355

Detection and Correction of Silent Data Corruption for Large-Scale High-Performance Computing  

SciTech Connect

Faults have become the norm rather than the exception for high-end computing on clusters with 10s/100s of thousands of cores. Exacerbating this situation, some of these faults remain undetected, manifesting themselves as silent errors that corrupt memory while applications continue to operate and report incorrect results. This paper studies the potential for redundancy to both detect and correct soft errors in MPI message-passing applications. Our study investigates the challenges inherent to detecting soft errors within MPI application while providing transparent MPI redundancy. By assuming a model wherein corruption in application data manifests itself by producing differing MPI message data between replicas, we study the best suited protocols for detecting and correcting MPI data that is the result of corruption. To experimentally validate our proposed detection and correction protocols, we introduce RedMPI, an MPI library which resides in the MPI profiling layer. RedMPI is capable of both online detection and correction of soft errors that occur in MPI applications without requiring any modifications to the application source by utilizing either double or triple redundancy. Our results indicate that our most efficient consistency protocol can successfully protect applications experiencing even high rates of silent data corruption with runtime overheads between 0% and 30% as compared to unprotected applications without redundancy. Using our fault injector within RedMPI, we observe that even a single soft error can have profound effects on running applications, causing a cascading pattern of corruption in most cases causes that spreads to all other processes. RedMPI's protection has been shown to successfully mitigate the effects of soft errors while allowing applications to complete with correct results even in the face of errors.

Fiala, David J [ORNL; Mueller, Frank [North Carolina State University; Engelmann, Christian [ORNL; Ferreira, Kurt Brian [Sandia National Laboratories (SNL); Brightwell, Ron [Sandia National Laboratories (SNL); Riesen, Rolf [IBM Research, Ireland

2012-07-01T23:59:59.000Z

356

Detection and Correction of Silent Data Corruption for Large-Scale High-Performance Computing  

SciTech Connect

Faults have become the norm rather than the exception for high-end computing on clusters with 10s/100s of thousands of cores. Exacerbating this situation, some of these faults remain undetected, manifesting themselves as silent errors that corrupt memory while applications continue to operate and report incorrect results. This paper studies the potential for redundancy to both detect and correct soft errors in MPI message-passing applications. Our study investigates the challenges inherent to detecting soft errors within MPI application while providing transparent MPI redundancy. By assuming a model wherein corruption in application data manifests itself by producing differing MPI message data between replicas, we study the best suited protocols for detecting and correcting MPI data that is the result of corruption. To experimentally validate our proposed detection and correction protocols, we introduce RedMPI, an MPI library which resides in the MPI profiling layer. RedMPI is capable of both online detection and correction of soft errors that occur in MPI applications without requiring any modifications to the application source by utilizing either double or triple redundancy. Our results indicate that our most efficient consistency protocol can successfully protect applications experiencing even high rates of silent data corruption with runtime overheads between 0% and 30% as compared to unprotected applications without redundancy. Using our fault injector within RedMPI, we observe that even a single soft error can have profound effects on running applications, causing a cascading pattern of corruption in most cases causes that spreads to all other processes. RedMPI's protection has been shown to successfully mitigate the effects of soft errors while allowing applications to complete with correct results even in the face of errors.

Fiala, David J [ORNL; Mueller, Frank [North Carolina State University; Engelmann, Christian [ORNL; Ferreira, Kurt Brian [Sandia National Laboratories (SNL); Brightwell, Ron [Sandia National Laboratories (SNL); Riesen, Rolf [IBM Research, Ireland

2013-01-01T23:59:59.000Z

357

Research on stable, high-efficiency, large-area, amorphous-silicon-based submodules  

SciTech Connect

The primary objective of this subcontract is to develop the technology for same bandgap, amorphous silicon tandem junction photovoltaic modules having an area of at least 900 cm{sup 2} with the goal of achieving an aperture area efficiency of 9%. A further objective is to demonstrate modules that retain 95% of their under standard light soaking conditions. Our approach to the attainment of these objective is based on the following distinctive technologies: (a) in-house deposition of SiO{sub 2}/SnO{sub 2}:F onto soda lime glass by APCVD to provide a textured, transparent electrode, (b) single chamber r.f. flow discharge deposition of the a-Si:H layers onto vertical substrates contained with high package density in a box carrier'' to which the discharge is confined (c) sputter deposition of highly reflecting, ZnO-based back contacts, and (d) laser scribing of the a-Si:H and electrodes with real-time scribe tracking to minimize area loss. Continued development of single junction amorphous silicon was aggressively pursued as proving ground for various optical enhancement schemes, new p-layers, and i-layers quality. We have rigorously demonstrated that the introduction of a transitional i-layer does not impair stability and that the initial gain in performance is retained. We have demonstrated a small improvement in cell stability through a post-fabrication treatment consisting of multiple, intense light flashes followed by sufficient annealing. Finally, several experiments have indicated that long term stability can be improved by overcoating the SnO{sub 2} with ZnO. 25 refs., 17 figs.

Delahoy, A.E.; Tonon, T.; Macneil, J. (Chronar Corp., Princeton, NJ (USA))

1991-06-01T23:59:59.000Z

358

Research on stable, high-efficiency, large-area, amorphous-silicon-based submodules  

DOE Green Energy (OSTI)

The primary objective of this subcontract is to develop the technology for same bandgap, amorphous silicon tandem junction photovoltaic modules having an area of at least 900 cm{sup 2} with the goal of achieving an aperture area efficiency of 9%. A further objective is to demonstrate modules that retain 95% of their under standard light soaking conditions. Our approach to the attainment of these objective is based on the following distinctive technologies: (a) in-house deposition of SiO{sub 2}/SnO{sub 2}:F onto soda lime glass by APCVD to provide a textured, transparent electrode, (b) single chamber r.f. flow discharge deposition of the a-Si:H layers onto vertical substrates contained with high package density in a box carrier'' to which the discharge is confined (c) sputter deposition of highly reflecting, ZnO-based back contacts, and (d) laser scribing of the a-Si:H and electrodes with real-time scribe tracking to minimize area loss. Continued development of single junction amorphous silicon was aggressively pursued as proving ground for various optical enhancement schemes, new p-layers, and i-layers quality. We have rigorously demonstrated that the introduction of a transitional i-layer does not impair stability and that the initial gain in performance is retained. We have demonstrated a small improvement in cell stability through a post-fabrication treatment consisting of multiple, intense light flashes followed by sufficient annealing. Finally, several experiments have indicated that long term stability can be improved by overcoating the SnO{sub 2} with ZnO. 25 refs., 17 figs.

Delahoy, A.E.; Tonon, T.; Macneil, J. (Chronar Corp., Princeton, NJ (USA))

1991-06-01T23:59:59.000Z

359

Detection and Correction of Silent Data Corruption for Large-Scale High-Performance Computing  

SciTech Connect

Faults have become the norm rather than the exception for high-end computing on clusters with 10s/100s of thousands of cores. Exacerbating this situation, some of these faults remain undetected, manifesting themselves as silent errors that corrupt memory while applications continue to operate and report incorrect results. This paper studies the potential for redundancy to both detect and correct soft errors in MPI message-passing applications. Our study investigates the challenges inherent to detecting soft errors within MPI application while providing transparent MPI redundancy. By assuming a model wherein corruption in application data manifests itself by producing differing MPI message data between replicas, we study the best suited protocols for detecting and correcting MPI data that is the result of corruption. To experimentally validate our proposed detection and correction protocols, we introduce RedMPI, an MPI library which resides in the MPI profiling layer. RedMPI is capable of both online detection and correction of soft errors that occur in MPI applications without requiring any modifications to the application source by utilizing either double or triple redundancy. Our results indicate that our most efficient consistency protocol can successfully protect applications experiencing even high rates of silent data corruption with runtime overheads between 0% and 30% as compared to unprotected applications without redundancy. Using our fault injector within RedMPI, we observe that even a single soft error can have profound effects on running applications, causing a cascading pattern of corruption in most cases causes that spreads to all other processes. RedMPI's protection has been shown to successfully mitigate the effects of soft errors while allowing applications to complete with correct results even in the face of errors.

Fiala, David J [ORNL; Mueller, Frank [North Carolina State University; Engelmann, Christian [ORNL; Ferreira, Kurt Brian [Sandia National Laboratories (SNL); Brightwell, Ron [Sandia National Laboratories (SNL); Riesen, Rolf [IBM Research, Ireland

2012-07-01T23:59:59.000Z

360

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

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 levelseliminating 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. Satcons new power conversion devices will eliminate these heavy transformers and connect a utility-scale solar power system directly to the grid. Satcons modular devices are designed to ensure reliabilityif one device fails it can be bypassed and the system can continue to run.

None

2012-01-25T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage large" from the National Library of EnergyBeta (NLEBeta).
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361

A CMOS threshold voltage reference source for very-low-voltage applications  

Science Conference Proceedings (OSTI)

This paper describes a CMOS voltage reference that makes use of weak inversion CMOS transistors and linear resistors, without the need for bipolar transistors. Its operation is analogous to the bandgap reference voltage, but the reference voltage is ... Keywords: Threshold voltage, Ultra-low-power, Very-low-voltage, Voltage reference

Luis H. C. Ferreira; Tales C. Pimenta; Robson L. Moreno

2008-12-01T23:59:59.000Z

362

Performance of Dynamic Voltage Restorer (DVR) against Voltage Sags and Swells Using Space Vector PWM Technique  

Science Conference Proceedings (OSTI)

Due to increasing complexity in the power system, voltage sags are now becoming one of the most significant power quality problems. Voltage sag is a short reduction voltage from nominal voltage, occurs in a short time. Short-lived voltage sags may not ... Keywords: Custom power, power quality, voltage sag, SPWM, SVPWM, DVR, PSCAD/EMTDC.

Palaparthi Ananthababu; Burle Trinadha; K. Ram Charan

2009-12-01T23:59:59.000Z

363

Research on stable, high-efficiency, large-area amorphous silicon based modules -- Task B  

DOE Green Energy (OSTI)

This report documents progress in developing a stable, high- efficiency, four-terminal hybrid tandem module. The module consists of a semi-transparent, thin-film silicon:hydrogen alloy (TFS) top circuit and a copper indium diselenide (CuInSe{sub 2}) bottom circuit. Film deposition and patterning processes were successfully extended to 0.4-m{sup 2} substrates. A 33.2-W (8.4% efficient) module with a 3970-cm{sup 2} aperture area and a white back reflector was demonstrated; without the back reflector, the module produced 30.2 W (7.6% efficient). Placing a laminated, 31.6-W, 8.1%-efficient CuInSe{sub 2} module underneath this TFS module, with an air gap between the two, produces 11.2 W (2.9% efficient) over a 3883-cm{sup 2} aperture area. Therefore, the four-terminal tandem power output is 41.4 W, translating to a 10.5% aperture-area efficiency. Subsequently, a 37.8-W (9.7% aperture-area efficiency) CuInSe{sub 2} module was demonstrated with a 3905-cm{sup 2} aperture area. Future performances of single-junction and tandem modules of this size were modeled, and predicted power outputs exceed 50 W (13% efficient) for CuInSe{sub 2} and 65 W (17% efficient) for TFS/CuInSe{sub 2} tandem modules.

Mitchell, K.W.; Willet, D.R. (Siemens Solar Industries, Camarillo, CA (USA))

1990-10-01T23:59:59.000Z

364

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

365

Lockout device for high voltage circuit breaker  

Science Conference Proceedings (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

366

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 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

367

Lookout 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 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

368

Fiber Optic Cables in High Voltage Environments  

Science Conference Proceedings (OSTI)

In recent years, it has become common for electric utilities to place fiber optic cables within their transmission rights-of-way. Overhead transmission power line corridors can provide the telecommunications industry with cost-effective alternative routes, and at the same time benefit the electric utilities by generating additional revenues using existing facilities. Also, within the power utility industry, reliable internal communications are vital to ensure ptotection and control of the power system. S...

2000-12-07T23:59:59.000Z

369

Voltage Node Arcing in the ICRH Antenna Vacuum Transmission Lines at JET  

Science Conference Proceedings (OSTI)

The observation of parasitic low-VSWR activity during operations of JET RF plant and the damage caused by arcing at the voltage-node in the vacuum transmission line (VTL) in 2004 highlight the importance of the problem of low-voltage breakdown in the ICRH systems. Simulations demonstrate little response of the RF circuit to the voltage-node arcing which explains why it remains largely unnoticed and complicates the design of protection systems. Analysis of the damage pattern produced by the voltage-node arcing suggests that multipactor-related phenomena occurring at elevated voltage thresholds in conditions of unfavorable VTL geometry are most plausible arc-provoking factors.

Monakhov, I.; Graham, M.; Mayoral, M.-L.; Nicholls, K.; Walden, A. [Euratom/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Bobkov, V. [Max-Planck Institut fuer Plasmaphysik, EURATOM Association, D-85748 Garching (Germany)

2007-09-28T23:59:59.000Z

370

Fiber-optic voltage sensor  

DOE Patents (OSTI)

A fiber optic voltage sensor is described which includes a source of light, a reference fiber for receiving a known percentage of the light and an electrostrictive element having terminals across which is applied, a voltage to be measured. The electrostrictive element is responsive to the applied voltage to assume an altered physical state. A measuring fiber also receives a known percentage of light from the light source and is secured about the electrostrictive element. The measuring fiber is provided with a cladding and exhibits an evanescent wave in the cladding. The measuring fiber has a known length which is altered when the electrostrictive element assumes its altered physical state. A differential sensor is provided which senses the intensity of light in both the reference fiber and the measuring fiber and provides an output indicative of the difference between the intensities.

Wood, C.B.

1990-01-01T23:59:59.000Z

371

Fiber-optic voltage sensor  

DOE Patents (OSTI)

A fiber optic voltage sensor is described which includes a source of light, a reference fiber for receiving a known percentage of the light and an electrostrictive element having terminals across which is applied, a voltage to be measured. The electrostrictive element is responsive to the applied voltage to assume an altered physical state. A measuring fiber also receives a known percentage of light from the light source and is secured about the electrostrictive element. The measuring fiber is provided with a cladding and exhibits an evanescent wave in the cladding. The measuring fiber has a known length which is altered when the electrostrictive element assumes its altered physical state. A differential sensor is provided which senses the intensity of light in both the reference fiber and the measuring fiber and provides an output indicative of the difference between the intensities.

Wood, C.B.

1990-12-31T23:59:59.000Z

372

Ancillary service details: Voltage control  

SciTech Connect

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

373

Portec Voltage Regulators: for Emergency Diesel Generators  

Science Conference Proceedings (OSTI)

This report contains information to help utilities address emergency diesel generator voltage regulator issues.

2004-12-15T23:59:59.000Z

374

Multilevel cascade voltage source inverter with seperate DC sources  

SciTech Connect

A multilevel cascade voltage source inverter having separate DC sources is described herein. This inverter is applicable to high voltage, high power applications such as flexible AC transmission systems (FACTS) including static VAR generation (SVG), power line conditioning, series compensation, phase shifting and voltage balancing and fuel cell and photovoltaic utility interface systems. The M-level inverter consists of at least one phase wherein each phase has a plurality of full bridge inverters equipped with an independent DC source. This inverter develops a near sinusoidal approximation voltage waveform with only one switching per cycle as the number of levels, M, is increased. The inverter may have either single-phase or multi-phase embodiments connected in either wye or delta configurations.

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

1997-01-01T23:59:59.000Z

375

Multilevel cascade voltage source inverter with seperate DC sources  

DOE Patents (OSTI)

A multilevel cascade voltage source inverter having separate DC sources is described herein. This inverter is applicable to high voltage, high power applications such as flexible AC transmission systems (FACTS) including static VAR generation (SVG), power line conditioning, series compensation, phase shifting and voltage balancing and fuel cell and photovoltaic utility interface systems. The M-level inverter consists of at least one phase wherein each phase has a plurality of full bridge inverters equipped with an independent DC source. This inverter develops a near sinusoidal approximation voltage waveform with only one switching per cycle as the number of levels, M, is increased. The inverter may have either single-phase or multi-phase embodiments connected in either wye or delta configurations.

Peng, Fang Zheng (Knoxville, TN); Lai, Jih-Sheng (Blacksburg, VA)

2002-01-01T23:59:59.000Z

376

Multilevel cascade voltage source inverter with separate DC sources  

DOE Patents (OSTI)

A multilevel cascade voltage source inverter having separate DC sources is described herein. This inverter is applicable to high voltage, high power applications such as flexible AC transmission systems (FACTS) including static VAR generation (SVG), power line conditioning, series compensation, phase shifting and voltage balancing and fuel cell and photovoltaic utility interface systems. The M-level inverter consists of at least one phase wherein each phase has a plurality of full bridge inverters equipped with an independent DC source. This inverter develops a near sinusoidal approximation voltage waveform with only one switching per cycle as the number of levels, M, is increased. The inverter may have either single-phase or multi-phase embodiments connected in either wye or delta configurations. 15 figs.

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

1997-06-24T23:59:59.000Z

377

Low-voltage-swing Monolithic DC-DC Conversion  

E-Print Network (OSTI)

AbstractA low-voltage-swing MOSFET gate drive technique is proposed in this paper for enhancing the efficiency characteristics of high-frequency-switching dcdc converters. The parasitic power dissipation of a dcdc converter is reduced by lowering the voltage swing of the power transistor gate drivers. A comprehensive circuit model of the parasitic impedances of a monolithic buck converter is presented. Closed-form expressions for the total power dissipation of a low-swing buck converter are proposed. The effect of reducing the MOSFET gate voltage swings is explored with the proposed circuit model. A range of design parameters is evaluated, permitting the development of a design space for full integration of active and passive devices of a low-swing buck converter on the same die, for a target CMOS technology. The optimum gate voltage swing of a power MOSFET that maximizes efficiency is lower than a standard full voltage swing. An efficiency of 88 % at a switching frequency of 102 MHz is achieved for a voltage conversion from 1.8 to 0.9 V with a low-swing dcdc converter based on a 0.18- m CMOS technology. The power dissipation of a low-swing dcdc converter is reduced by 27.9 % as compared to a standard full-swing dcdc converter. Index TermsBuck converter, dcdc converters, enhanced efficiency, high frequency, low power, low swing, monolithic integration, on-chip voltage conversion, parameter optimization, parasitic impedances, power dissipation modeling, power supply, reduced energy dissipation, reduced voltage swing, switching voltage regulator. I.

Volkan Kursun; Siva G. Narendra; Vivek K. De; Eby G. Friedman

2004-01-01T23:59:59.000Z

378

Probabilistic voltage assessment and VAR compensation  

SciTech Connect

The system voltage profile subject to system elements' forced outage is accessed. Two system voltage reliability indexes are evaluated: the loss of voltage probability, and the expected voltage violation. A similar set of two voltage reliability indexes are also calculated for every load bus in the system. A simple VAR compensation approach is introduced. It enhances the voltage profile assuming a maximum of three overlapping element outages can occur. For purposes of demonstration, the system and load bus voltage reliability indexes are calculated for the AEP 30-bus system. Results of applying the proposed VAR compensation scheme to the 30-bus system are also presented and discussed.

Sharaf, T.A.M.; Berg, G.J.

1988-01-01T23:59:59.000Z

379

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

380

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. 6 figs.

Crawford, T.M.; Davidson, J.R.; Woods, G.K.

1999-08-17T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage large" 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

Constraints on Lorentz Invariance Violating Quantum Gravity and Large Extra Dimensions Models using High Energy Gamma Ray Observations  

E-Print Network (OSTI)

Observations of the multi-TeV spectra of the nearby BL objects Mkn 421 and Mkn 501 exhibit the high energy cutoffs predicted to be the result of intergalactic annihilation interactions, primarily with infrared photons having a flux level as determined by various astronomical observations. After correction for this absorption effect, the derived intrinsic spectra of these multi-TeV sources can be explained within the framework of simple synchrotron self-Compton emission models. Stecker and Glashow have shown that the existence of such annihilations via electron-positron pair production interactions up to an energy of 20 TeV puts strong constraints on Lorentz invariance violation. Such constraints have important implications for Lorentz invariance violating (LIV) quantum gravity models as well as LIV models involving large extra dimensions. We also discuss the implications of observations of high energy ?-rays from the Crab Nebula on constraining quantum gravity models.

F. W. Stecker

2003-01-01T23:59:59.000Z

382

Study of the Variation of Transverse Voltage in the 4 Rod Crab Cavity for LHC  

Science Conference Proceedings (OSTI)

The planned high luminosity upgrade to LHC will utilise crab cavities to rotate the beam in order to increase the luminosity in the presence of a finite crossing angle. A compact design is required in order for the cavities to fit between opposing beam-lines. In this paper we discuss we discuss one option for the LHC crab cavity based on a 4 rod TEM deflecting cavity. Due to the large transverse size of the LHC beam the cavity is required to have a large aperture while maintaining a constant transverse voltage across the aperture. The cavity has been optimised to minimise the variation of the transverse voltage while keeping the peak surface electric and magnetic fields low for a given kick. This is achieved while fitting within the strict design space of the LHC. The variation of deflecting voltage across the aperture has been studied numerically and compared with numerical and analytical estimates of other deflecting cavity types. Performance measurements an aluminium prototype of this cavity are presented and compared to the simulated design.

B. Hall, G. Burt, C. Lingwood, R. Rimmer, H. Wang

2011-04-01T23:59:59.000Z

383

HIGH-TEMPERATURE ELECTROLYSIS FOR LARGE-SCALE HYDROGEN AND SYNGAS PRODUCTION FROM NUCLEAR ENERGY SYSTEM SIMULATION AND ECONOMICS  

DOE Green Energy (OSTI)

A research and development program is under way at the Idaho National Laboratory (INL) to assess the technological and scale-up issues associated with the implementation of solid-oxide electrolysis cell technology for efficient high-temperature hydrogen production from steam. This work is supported by the US Department of Energy, Office of Nuclear Energy, under the Nuclear Hydrogen Initiative. This paper will provide an overview of large-scale system modeling results and economic analyses that have been completed to date. System analysis results have been obtained using the commercial code UniSim, augmented with a custom high-temperature electrolyzer module. Economic analysis results were based on the DOE H2A analysis methodology. The process flow diagrams for the system simulations include an advanced nuclear reactor as a source of high-temperature process heat, a power cycle and a coupled steam electrolysis loop. Several reactor types and power cycles have been considered, over a range of reactor outlet temperatures. Pure steam electrolysis for hydrogen production as well as coelectrolysis for syngas production from steam/carbon dioxide mixtures have both been considered. In addition, the feasibility of coupling the high-temperature electrolysis process to biomass and coal-based synthetic fuels production has been considered. These simulations demonstrate that the addition of supplementary nuclear hydrogen to synthetic fuels production from any carbon source minimizes emissions of carbon dioxide during the production process.

J. E. O'Brien; M. G. McKellar; E. A. Harvego; C. M. Stoots

2009-05-01T23:59:59.000Z

384

ETTM: Low Voltage System Protection and Coordination Computer-Based Training Version 1.0  

Science Conference Proceedings (OSTI)

ETTM Low Voltage System Protection and Coordination is a computer-based training module that allows users to access training when desired and review it at their own pace. It provides graphics and limited interactive features to enhance learning. Low voltage power systems are generally classified as AC power systems operating at the 120 600 Volt level. Because they often serve a large number of diverse loads in residences, businesses, and power plants, low voltage power systems present a unique set of cha...

2010-11-30T23:59:59.000Z

385

Phase-Field Simulations of a Simple Voltage-Controlled Magnetic ...  

Science Conference Proceedings (OSTI)

The voltage-induced magnetization and/or magnetic domain switching dynamics in ... Our results offer a promising new way towards future high-performance...

386

Effect of Voltage Pulse Duration on Surface Properties of Micro Arc ...  

Science Conference Proceedings (OSTI)

Durations of successive positive and negative voltage pulses in one cycle ... Electrodeposition of Ni-Al-Cr Bond Coat and Its High Temperature Behavior on...

387

Triple-Voltage DC-DC Converter - Oak Ridge National Laboratory  

Overall Project Objective ... Saving in the switch and gate drive component count increases ... power transfer between the low-voltage buses and the high

388

Implementation of a Large Scale Control System for a High-Energy Physics Detector: The CMS Silicon Strip Tracker  

E-Print Network (OSTI)

Control systems for modern High-Energy Physics (HEP) detectors are large distributed software systems managing a significant data volume and implementing complex operational procedures. The control software for the LHC experiments at CERN is built on top of a commercial software used in industrial automation. However, HEP specific requirements call for extended functionalities. This thesis focuses on the design and implementation of the control system for the CMS Silicon Strip Tracker but presents some general strategies that have been applied in other contexts. Specific design solutions are developed to ensure acceptable response times and to provide the operator with an effective summary of the status of the devices. Detector safety is guaranteed by proper configuration of independent hardware systems. A software protection mechanism is used to avoid the widespread intervention of the hardware safety and to inhibit dangerous commands. A wizard approach allows non expert operators to recover error situations...

Masetti, Lorenzo; Fischer, Peter

2011-01-01T23:59:59.000Z

389

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-on-a-chip. It is mainly due to the limited power dissipation within a small area and the costs related to the packaging and thermal management. In this research work, two low-voltage, low-power integrated circuits used for data communication systems are introduced. The first one is a high performance continuous-time linear phase filter with automatic frequency tuning. The filter can be used in hard disk driver systems and wired communication systems such as 1000Base-T transceivers. A pseudo-differential operational transconductance amplifier (OTA) based on transistors operating in triode region is used to achieve a large linear signal swing with low-voltage supplies. A common-mode (CM) control circuit that combines common-mode feedback (CMFB), common-mode feedforward (CMFF), and adaptive-bias has been proposed. With a 2.3V single supply, the filter?s total harmonic distortion is less than ?44dB for a 2VPP differential input, which is due to the well controlled CM behavior. The ratio of the root mean square value of the ac signal to the power supply voltage is around 31%, which is much better than previous realizations. The second integrated circuit includes two LVDS drivers used for high-speed point-to-point links. By removing the stacked switches used in the conventional structures, both LVDS drivers can operate with ultra low-voltage supplies. Although the Double Current Sources (DCS) LVDS driver draws twice minimum static current as required by the signal swing, it is quite simple and achieves very high speed operation. The Switchable Current Sources (SCS) LVDS driver, by dynamically switching the current sources, draws minimum static current and reduces the power consumption by 60% compared to the previously reported LVDS drivers. Both LVDS drivers are compliant to the standards and operate at data rates up to gigabits-per-second.

Chen, Mingdeng

2003-12-01T23:59:59.000Z

390

Voltage Control Devices on the IEEE 8500 Node Test Feeder  

SciTech Connect

The IEEE Test Cases provide researchers with distribution system models that can be used to validate new analytic methods. The newest of these models is the 8500-node test feeder which contains multiple devices for voltage control. In addition to a substation regulator there are multiple inline regulators as well as capacitor banks. This paper will discuss the detail in which voltage control devises should be modeled when examining large distribution systems. This discussion will include issues associated with power flow analysis for a single time step as well as for time series analysis.

Schneider, Kevin P.; Fuller, Jason C.

2010-01-06T23:59:59.000Z

391

Point of Collapse and Continuation Methods for Large AC/DC Systems  

E-Print Network (OSTI)

This paper describes the implementation of both Point of Collapse (PoC) methods and continuation methods for the computation of voltage collapse points (saddle-node bifurcations) in large ac/dc systems. A comparison of the performance of these methods is presented for real systems of up to 2158 buses. The paper discusses computational details of the implementation of the PoC and continuation methods, and the unique challenges encountered due to the presence of high voltage direct current (HVDC) transmission, area interchange power control, regulating transformers, and voltage and reactive power limits. The characteristics of a robust PoC power ow program are presented, and its application to detection and solution of voltage stability problems is demonstrated.

Claudio A. Caizares; Fernando L. Alvarado

1993-01-01T23:59:59.000Z

392

Voltage unbalance effects on induction motor performance  

Science Conference Proceedings (OSTI)

The reliability of electric drives and driven motors depends on the quality of the power supply voltage especially in the critical industrial process. In this work, a theoretical study of the effects of voltage unbalances, sags and swells on induction ... Keywords: efficiency, power losses and derating factor, sags, symmetrical components, voltage unbalance

L. Refoufi; H. Bentarzi; F. Z. Dekhandji

2006-09-01T23:59:59.000Z

393

An amplifier for use with large-area photodiodes  

DOE Green Energy (OSTI)

We describe a high-gain ({approximately}10{sup 7}) amplifier for use with large-area silicon photodiodes for monitoring the intensity of plasma light from fusion experiments. To achieve the necessary gain without saturating the output signal, the amplifier design incorporates a bootstrap technique and capacitive coupling between amplifier stages. This design eliminates voltage offset at the amplifier output due to detector leakage, while retaining desirable low-frequency response characteristics.

Dyer, G.R.; Uckan, T. (Fusion Energy Division, Oak Ridge National Laboratory, Oak Ridge, TN (USA))

1990-12-01T23:59:59.000Z

394

High PRF high current switch  

DOE Green Energy (OSTI)

A triggerable, high voltage, high current, spark gap switch for use in pu power systems. The device comprises a pair of electrodes in a high pressure hydrogen environment that is triggered by introducing an arc between one electrode and a trigger pin. Unusually high repetition rates may be obtained by undervolting the switch, i.e., operating the trigger at voltages much below the self-breakdown voltage of the device.

Moran, Stuart L. (Fredericksburg, VA); Hutcherson, R. Kenneth (College Park, MD)

1990-03-27T23:59:59.000Z

395

Opto-Electronics in Large Array Gas Detector Systems  

E-Print Network (OSTI)

Large array gas detector systems are used in particle and nuclear physics experiments involving high-energy nucleon-nucleon and heavy-ion collisions. We have observed that in large array gas detector systems the momentary discharges inside the detector cells result in slowdown of High Voltage conditioning and possible hindrances in signal processing. We have explored the opto-electronic devices like the opto-coupler, optical fibre and signal processing circuit, which provide successful monitoring procedures and preventive measures to overcome the challenges produced in such complex detector systems.

M. R. Dutta Majumdar; Debasish Das; Tapan K. Nayak

2005-12-23T23:59:59.000Z

396

GLOBULAR CLUSTER ABUNDANCES FROM HIGH-RESOLUTION, INTEGRATED-LIGHT SPECTROSCOPY. III. THE LARGE MAGELLANIC CLOUD: Fe AND AGES  

Science Conference Proceedings (OSTI)

In this paper, we refine our method for the abundance analysis of high-resolution spectroscopy of the integrated light of unresolved globular clusters (GCs). This method was previously demonstrated for the analysis of old (>10 Gyr) Milky Way (MW) GCs. Here, we extend the technique to young clusters using a training set of nine GCs in the Large Magellanic Cloud. Depending on the signal-to-noise ratio of the data, we use 20-100 Fe lines per cluster to successfully constrain the ages of old clusters to within a {approx}5 Gyr range, the ages of {approx}2 Gyr clusters to a 1-2 Gyr range, and the ages of the youngest clusters (0.05-1 Gyr) to a {approx}200 Myr range. We also demonstrate that we can measure [Fe/H] in clusters with any age less than 12 Gyr with similar or only slightly larger uncertainties (0.1-0.25 dex) than those obtained for old MW GCs (0.1 dex); the slightly larger uncertainties are due to the rapid evolution in stellar populations at these ages. In this paper, we present only Fe abundances and ages. In the next paper in this series, we present our complete analysis of {approx}20 elements for which we are able to measure abundances. For several of the clusters in this sample, there are no high-resolution abundances in the literature from individual member stars; our results are the first detailed chemical abundances available. The spectra used in this paper were obtained at Las Campanas with the echelle on the du Pont Telescope and with the MIKE spectrograph on the Magellan Clay Telescope.

Colucci, Janet E.; Bernstein, Rebecca A. [Department of Astronomy and Astrophysics, 1156 High Street, UCO/Lick Observatory, University of California, Santa Cruz, CA 95064 (United States); Cameron, Scott A. [Astronomy Department, 500 Church Street, University of Michigan, Ann Arbor, MI 48109-1090 (United States); McWilliam, Andrew, E-mail: jcolucci@ucolick.org, E-mail: rab@ucolick.org, E-mail: sacamero@umich.edu, E-mail: andy@ociw.edu [The Observatories of the Carnegie Institute of Washington, 813 Santa Barbara Street, Pasadena, CA 91101-1292 (United States)

2011-07-01T23:59:59.000Z

397

A STUDY OF HIGH-ORDER NON-GAUSSIANITY WITH APPLICATIONS TO MASSIVE CLUSTERS AND LARGE VOIDS  

SciTech Connect

The statistical meaning of the local non-Gaussianity parameters f{sub NL} and g{sub NL} is examined in detail. Their relations to the skewness and the kurtosis of the initial distribution are shown to obey simple fitting formulae, accurate on galaxy-cluster scales. We argue that the knowledge of f{sub NL} and g{sub NL} is insufficient for reconstructing a well-defined distribution of primordial fluctuations. Requiring the reconstructed probability density function (pdf) to be positive enforces a theoretical lower bound g{sub NL} {approx}> -1.2 x 10{sup 5}, competitive with the observational bounds in the current literature. By weakening the statistical significance of f{sub NL} and g{sub NL}, it is possible to reconstruct a well-defined pdf by using a truncated Edgeworth series. We give some general guidelines on the use of such a series, noting in particular that (1) the Edgeworth series cannot represent models with nonzero f{sub NL}, unless g{sub NL} is nonzero, and also (2) the series cannot represent models with g{sub NL} < 0, unless some higher-order non-Gaussianities are known. Finally, we apply the Edgeworth series to calculate the effects of g{sub NL} on the abundances of massive clusters and large voids. We show that the abundance of voids may generally be more sensitive to high-order non-Gaussianities than the cluster abundance.

Chongchitnan, Sirichai; Silk, Joseph, E-mail: siri@astro.ox.ac.u [Oxford Astrophysics Denys, Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom)

2010-11-20T23:59:59.000Z

398

Influence of voltage drop to electric drive with induction motor and voltage sourced inverter  

Science Conference Proceedings (OSTI)

This paper solves problematic of immunity from the voltage drop of the power supply of the electric drive with induction motor with Voltage-Fed inverter. There are reflected opportune control algorithms for the quickly to change of working regime from ... Keywords: electric drive with induction motor, electric drive with voltage sourced inverter, voltage drop

P. Bene; J. Fo?t; M. Pittermann

2011-09-01T23:59:59.000Z

399

Dynamic Voltage Regulation Using Distributed Energy Resources  

Science Conference Proceedings (OSTI)

Many distributed energy resources (DE) are near load centres and equipped with power electronics converters to interface with the grid, therefore it is feasible for DE to provide ancillary services such as voltage regulation, nonactive power compensation, and power factor correction. A synchronous condenser and a microturbine with an inverter interface are implemented in parallel in a distribution system to regulate the local voltage. Voltage control schemes of the inverter and the synchronous condenser are developed. The experimental results show that both the inverter and the synchronous condenser can regulate the local voltage instantaneously, while the dynamic response of the inverter is faster than the synchronous condenser; and that integrated voltage regulation (multiple DE perform voltage regulation) can increase the voltage regulation capability, increase the lifetime of the equipment, and reduce the capital and operation costs.

Xu, Yan [ORNL; Rizy, D Tom [ORNL; Li, Fangxing [ORNL; Kueck, John D [ORNL

2007-01-01T23:59:59.000Z

400

High Bandwidth Differential Amplifier for Shock Experiments  

Science Conference Proceedings (OSTI)

We developed a high bandwidth differential amplifier for gas gun shock experiments. The circuit has a bandwidth up to 1 GHz, and is capable of measuring signals of ?1.5 V with a common mode rejection of 250 V. Conductivity measurements of gas gun targets are measured by flowing high currents through the targets. The voltage is measured across the target using a technique similar to a four-point probe. Because of the design of the current source and load, the target voltage is approximately 250 V relative to ground. Since the expected voltage change in the target is < 1 V, the differential amplifier must have a large common mode rejection. Various amplifying designs are shown, although the increased amplification decreases bandwidth. Bench tests show that the amplifier can withstand significant common mode DC voltage and measure 10 ns, and 50 mV signals.

Ross, P., Tran, V., Chau, R.

2012-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage large" 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

Evaluation of local content strategies to plan large engineering projects in the oil & gas industry in high risk country areas  

Science Conference Proceedings (OSTI)

The Local content of a complex project is an important variable to create value and increase the overall sustainability of large engineering projects in the Oil & Gas industry, especially in the developing countries. The paper proposes a method to ... Keywords: causal knowledge map, large engineering projects, local content, scenario analysis

Troncone Enzo Piermichele; De Falco Massimo; Gallo Mos; Santillo Liberatina Carmela; Pier Alberto Viecelli

2012-01-01T23:59:59.000Z

402

Voltage holding study of 1 MeV accelerator for ITER neutral beam injector  

Science Conference Proceedings (OSTI)

Voltage holding test on MeV accelerator indicated that sustainable voltage was a half of that of ideal quasi-Rogowski electrode. It was suggested that the emission of the clumps is enhanced by a local electric field concentration, which leads to discharge initiation at lower voltage. To reduce the electric field concentration in the MeV accelerator, gaps between the grid supports were expanded and curvature radii at the support corners were increased. After the modifications, the accelerator succeeded in sustaining -1 MV in vacuum without beam acceleration. However, the beam energy was still limited at a level of 900 keV with a beam current density of 150 A/m{sup 2} (346 mA) where the 3 x 5 apertures were used. Measurement of the beam profile revealed that deflection of the H{sup -} ions was large and a part of the H{sup -} ions was intercepted at the acceleration grid. This causes high heat load on the grids and the breakdowns during beam acceleration. To suppress the direct interception, new grid system was designed with proper aperture displacement based on a 3D beam trajectory analysis. As the result, the beam deflection was compensated and the voltage holding during the beam acceleration was improved. Beam parameter of the MeV accelerator was increased to 980 keV, 185 A/m{sup 2} (427 mA), which is close to the requirement of ITER accelerator (1 MeV, 200 A/m{sup 2}).

Taniguchi, M.; Kashiwagi, M.; Umeda, N.; Dairaku, M.; Takemoto, J.; Tobari, H.; Tsuchida, K.; Yamanaka, H.; Watanabe, K.; Kojima, A.; Hanada, M.; Sakamoto, K.; Inoue, T. [Japan Atomic Energy Agency (JAEA), 801-1 Mukoyama, Naka, Ibaraki 311-0193 (Japan)

2012-02-15T23:59:59.000Z

403

Abstract: Towards Highly Accurate Large-Scale Ab Initio Calculations Using Fragment Molecular Orbital Method in GAMESS  

Science Conference Proceedings (OSTI)

One of the major challenges of modern quantum chemistry (QC) is to apply it to large systems with thousands of correlated electrons and basis functions. The availability of supercomputers and development of novel methods are necessary to realize this ...

Maricris L. Mayes, Graham D. Fletcher, Mark S. Gordon

2012-11-01T23:59:59.000Z

404

Abstract Large numbers of maize chromosome 9 can be collected with high purity by flow cytometric sorting of  

E-Print Network (OSTI)

of this reporter system is fluorescence-activated cell-sorter (FACS) screening [22,23] of large pools of mammalian to be optimistic about biodiesel: seed meal as a valuable soil amendment Michael F. Cohen and Mark Mazzola USDA

Gill, Kulvinder

405

Easily disassembled electrical connector for high voltage, high frequency connections  

DOE Patents (OSTI)

An easily accessible electrical connector capable of rapid assembly and disassembly is described wherein a wide metal conductor sheet may be evenly contacted over the entire width of the conductor sheet by opposing surfaces on the connector which provide an even clamping pressure against opposite surfaces of the metal conductor sheet using a single threaded actuating screw. 13 figures.

Milner, J.R.

1994-05-10T23:59:59.000Z

406

Needs and Wants-Suggestions for High Voltage and High ...  

Science Conference Proceedings (OSTI)

... generation capacity installed or in backlog, Generated more than one billion kilowatt hours of ultra-clean power. Page 3. ...

2012-06-08T23:59:59.000Z

407

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

408

Lowering Power using the Voltage Identification Bit  

E-Print Network (OSTI)

Voltage identification is a form of adaptive voltage scaling (AVS). The voltage-identification technique described in this application note enables certain devices in the Virtex-7 family to be operated at a lower voltage of 0.9V while delivering the same specified performance as that of a device operating at the nominal supply voltage of 1.0V. Voltage identification capable devices consume approximately 30 % lower worst case (maximum) static power and correspondingly dissipate less heat. Reduced power consumption is a desirable characteristic and one that Xilinx 7 series FPGAs fulfill in multiple ways. The primary purpose of the voltage-identification technique is to reduce the worst-case power consumption of-1C devices. However, the significance of the voltage-identification technique goes beyond an individual device dissipating less energy, it also can lower the overall system cost. Power supplies and thermal management requirements are normally specified based on the worst-case power demands of all the systems components. Although the 7 series FPGAs-1C devices are the most cost-effective, the total cost of a product is the sum of all parts, and costs associated with the power supply and thermal management can be significant. The voltage-identification technique specifically reduces worst-case power consumption, which reduces the overall costs associated with specifying a larger power supply, requiring a heat sink, adding forced air cooling, or including similar devices. This application note shows the technical aspects of implementing the voltage-identification technique and introduces a reference design for the VC707 evaluation kit. It also explains how voltage identification fits into the complete power portfolio of Virtex-7 FPGAs and highlights the benefits of using the voltage-identification technique to reduce power consumption and system costs.

Ken Chapman; Jameel Hussein

2012-01-01T23:59:59.000Z

409

The effect of DVR location for enhancing voltage sag  

Science Conference Proceedings (OSTI)

Recently, Dynamic Voltage Restorer (DVR) has become a popular power electronic device as a protection for sensitive loads from voltage sag. Voltage sag widely known as one of the major problem in power quality, it is defined as a short reduction of voltage ... Keywords: dynamic voltage restorer, power quality, voltage sag

Rohanim Ibrahim; Ahmed M. A. Haidar; M. Zahim; Herbert Iu

2010-03-01T23:59:59.000Z

410

Emergency Diesel Generator Voltage Regulator Guidelines  

Science Conference Proceedings (OSTI)

This product kit, containing six separate documents, provides information to help utilities address emergency diesel generator voltage regulator issues and maintenance.

2005-12-20T23:59:59.000Z

411

Quantum Voltage System Development and Dissemination  

Science Conference Proceedings (OSTI)

... of the unit of electric potential difference, the volt, and precise techniques for measuring voltage are essential to the electrical ... Facilities/Tools Used: ...

2012-11-14T23:59:59.000Z

412

Voltage Source Converter Technology for Offshore Grids.  

E-Print Network (OSTI)

??This master thesis has investigated the possible application of voltage source converters (VSC) for the interconnection of offshore installations, i.e. wind farms and petroleum platforms, (more)

Vormedal, Pl Kristian Myhrer

2010-01-01T23:59:59.000Z

413

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

DOE Green Energy (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

414

Voltage stability/security assessment and on-line control  

SciTech Connect

Project RP3040-1 was initiated in 1989, and concluded with the release of the Voltage Stability analysis program, VSTAB, in 1992. VSTAB is a production grade program for voltage stability assessment of large complex power systems. During the course of the RP3040-1, much effort was spent in developing a clear understanding of voltage stability and in defining the special modeling and analytical techniques required to accurately capture the phenomenon through simulation. The result was the development of new steady state methods which can complement the dynamic simulation methods currently available with EPRI's Extended Transient/Midterm Stability Program (ETMSP). VSTAB uses an enhanced powerflow combined with a specially developed modal analysis algorithm to provide information regarding both the proximity to, and mechanism of, voltage instability. The program is fast, easy to use, and comprehensive in both modeling and analysis features. This Programmer's Manual documents the structure and code details of VSTAB. It is intended as a reference document for those required to maintain or enhance the VSTAB program. For details on analytical techniques used in the program, readers are directed to the VSTAB Application Guide and Final Report for project RP3040-1.

Morison, G.K.; Gao, B.; Hamadanizadeh, H. (Ontario Hydro, Toronto, ON (Canada))

1993-04-01T23:59:59.000Z

415

Capturing power at higher voltages from arrays of microbial fuel cells without voltage reversal  

E-Print Network (OSTI)

is too low to be used directly for many practical applications. For example, a single light emitting diode (LED) requires a minimum voltage of 2 V.2 Thus, effective methods of boosting MFC voltages

416

Aalborg Universitet Mitigation of Voltage Sags in CIGRE Low Voltage Distribution Network  

E-Print Network (OSTI)

software version 15.0. Index Terms--Wind Turbine Generator (WTG), Photovoltaic (PV), Voltage Source of voltage sags. I. INTRODUCTION Power quality, reliability and stability are the prime requirement of modern

Bak-Jensen, Birgitte

417

Energy-efficient datapath scheduling using multiple voltages and dynamic clocking  

Science Conference Proceedings (OSTI)

Recently, dynamic frequency scaling has been explored at the CPU and system levels for power optimization. Low-power datapath scheduling using multiple supply voltages has been well researched. In this work, we develop new datapath scheduling algorithms ... Keywords: High-level synthesis, dynamic frequency clocking, low-power datapath synthesis, multiple voltage scheduling, resource-constrained scheduling, time-constrained scheduling

Saraju P. Mohanty; N. Ranganathan

2005-04-01T23:59:59.000Z

418

Voltage-tunable singlet-triplet transition in lateral quantum dots  

E-Print Network (OSTI)

Results of calculations and high source-drain transport measurements are presented which demonstrate voltage-tunable entanglement of electron pairs in lateral quantum dots. At a fixed magnetic field, the application of a judiciously-chosen gate voltage alters the ground-state of an electron pair from an entagled spin singlet to a spin triplet.

Jordan Kyriakidis; M. Pioro-Ladriere; M. Ciorga; A. S. Sachrajda; P. Hawrylak

2001-11-28T23:59:59.000Z

419

Voltage Stability Studies for Southern Company Services  

Science Conference Proceedings (OSTI)

This report describes a study conducted under an EPRI Tailored Collaboration project to develop and demonstrate procedures for the assessment of voltage security of the Southern Electric System (SES). The contractor used EPRI steady-state analysis tools including VSTAB (Voltage STABility assessment program) to assess stability margins and verified them using EPRI dynamic tools including ETMSP (Extended Transient / Mid-term Stability Program).

1997-12-31T23:59:59.000Z

420

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 when it 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, W.M.

1991-03-19T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage large" 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

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

422

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

SciTech Connect

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

423

NREL: Measurements and Characterization - Current Versus Voltage  

NLE Websites -- All DOE Office Websites (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

424

Flexible method for monitoring fuel cell voltage  

DOE Patents (OSTI)

A method for equalizing the measured voltage of each cluster in a fuel cell stack wherein at least one of the clusters has a different number of cells than the identical number of cells in the remaining clusters by creating a pseudo voltage for the different cell numbered cluster. The average cell voltage of the all of the cells in the fuel cell stack is calculated and multiplied by a constant equal to the difference in the number of cells in the identical cell clusters and the number of cells in the different numbered cell cluster. The resultant product is added to the actual voltage measured across the different numbered cell cluster to create a pseudo voltage which is equivalent in cell number to the number of cells in the other identical numbered cell clusters.

Mowery, Kenneth D. (Noblesville, IN); Ripley, Eugene V. (Russiaville, IN)

2002-01-01T23:59:59.000Z

425

Corona and Motor Voltage Interim Report  

SciTech Connect

It has been suggested that to meet the FreedomCAR objectives for cost, size, weight, efficiency, and reliability higher buss voltages be utilized in HEV and FC automotive applications. The reasoning is that since electric power is equal to the product of voltage and current for a given power a higher voltage and lower current would result in smaller cable and inverter switching components. Consequently, the system can be lighter and smaller. On the other hand, higher voltages are known to require better and thicker electrical insulation that reduce the available slot area for motor windings. One cause of slow insulation breakdown is corona that gradually erodes the insulation and shortens the life expectancy of the motor. This study reports on the results of a study on corona initiating voltages for mush-wound and bobbin-wound stators. A unique testing method is illustrated.

Hsu, J.S.

2005-05-06T23:59:59.000Z

426

High-Resolution Large-Eddy Simulations of Scalar Transport in Atmospheric Boundary Layer Flow over Complex Terrain  

Science Conference Proceedings (OSTI)

This paper presents high-resolution numerical simulations of the atmospheric flow and concentration fields accompanying scalar transport and diffusion from a point source in complex terrain. Scalar dispersion is affected not only by mean flow, ...

Takenobu Michioka; Fotini Katopodes Chow

2008-12-01T23:59:59.000Z

427

Large-Scale Testing and High-Fidelity Simulation Capabilities at Sandia National Laboratories to Support Space Power and Propulsion  

SciTech Connect

Sandia National Laboratories, as a Department of Energy, National Nuclear Security Agency, has major responsibility to ensure the safety and security needs of nuclear weapons. As such, with an experienced research staff, Sandia maintains a spectrum of modeling and simulation capabilities integrated with experimental and large-scale test capabilities. This expertise and these capabilities offer considerable resources for addressing issues of interest to the space power and propulsion communities. This paper presents Sandia's capability to perform thermal qualification (analysis, test, modeling and simulation) using a representative weapon system as an example demonstrating the potential to support NASA's Lunar Reactor System.

Dobranich, Dean [Thermal and Reactive Processes Department, Sandia National Laboratories Albuquerque, NM 87185 (United States); Blanchat, Thomas K. [Fire Science and Technology Department, Sandia National Laboratories Albuquerque, NM 87185 (United States)

2008-01-21T23:59:59.000Z

428

High-Dielectric Constant, High-Temperature Ceramic Capacitors for ...  

Science Conference Proceedings (OSTI)

Growth of Thick, On-Axis SiC Epitaxial Layers by High Temperature Halide CVD for High Voltage Power Devices High-Dielectric Constant, High-Temperature...

429

Low-voltage cathodoluminescence of europium-activated yttrium orthovanadate  

Science Conference Proceedings (OSTI)

Emissive flat panel display systems operating in full color demand higher performance at low voltages (ca. 501000 V) from cathodoluminescent (CL) phosphors than cathode ray tubes require. Hydrothermal synthesis has been suggested as a route to phosphors with improved efficiencies, lower voltage thresholds, and increased saturation power. This hypothesis was tested in europium-doped yttrium orthovanadate (YVO{sub 4}:Eu), an efficient, red emitting CL phosphor. The CL efficiency of YVO{sub 4}:Eu crystallized from aqueous solution at 200{degrees}C is relatively low until it is annealed. The distribution of particle sizes in the low-temperature phosphor is similar to that in material made via a solid-state route, but crystallites remain much smaller (ca. 400 {Angstrom}) until they are annealed. These observations, along with the anomalously strong dependence of CL intensity on europium concentration, support a model in which efficiency principally depends on crystallite size. CL efficiency of both solid state and hydrothermal YVO{sub 4}:Eu increases with voltage at constant power. Surface-bound electrons are likely the dominant influence on efficiency at voltages near threshold. Saturation power is independent of synthetic route. It is apparent that the CL properties of hydrothermally synthesized YVO{sub 4}:Eu are essentially the same as those of YVO{sub 4}:Eu produced via conventional, high-temperature routes.

Phillips, M.L.F.

1995-03-01T23:59:59.000Z

430

A Stable Vanadium Redox-Flow Battery with High Energy Density for Large-scale Energy Storage  

SciTech Connect

Low cost, high performance redox flow batteries are highly demanded for up to multi-megawatt levels of renewable and grid energy storage. Here, we report a new vanadium redox flow battery with a significant improvement over the current technologies. This new battery utilizes a sulfate-chloride mixed solution, which is capable of dissolving more than 2.5 M vanadium or about a 70% increase in the energy storage capacity over the current vanadium sulfate system. More importantly, the new electrolyte remains stable over a wide temperature range of -5 to 60oC, potentially eliminating the need of active heat management. Its high energy density, broad operational temperature window, and excellent electrochemical performance would lead to a significant reduction in the cost of energy storage, thus accelerating its market penetration.

Li, Liyu; Kim, Soowhan; Wang, Wei; Vijayakumar, M.; Nie, Zimin; Chen, Baowei; Zhang, Jianlu; Xia, Guanguang; Hu, Jian Z.; Graff, Gordon L.; Liu, Jun; Yang, Zhenguo

2011-05-01T23:59:59.000Z

431

Voltage controlled spintronics device for logic applications.  

SciTech Connect

We consider logic device concepts based on our previously proposed spintronics device element whose magnetization orientation is controlled by application of a bias voltage instead of a magnetic field. The basic building block is the voltage-controlled rotation (VCR) element that consists of a four-layer structure--two ferromagnetic layers separated by both nanometer-thick insulator and metallic spacer layers. The interlayer exchange coupling between the two ferromagnetic layers oscillates as a function of applied voltage. We illustrate transistor-like concepts and re-programmable logic gates based on VCR elements.

Bader, S. D.; You, C.-Y.

1999-09-03T23:59:59.000Z

432

Voltage controlled spintronic devices for logic applications  

SciTech Connect

We consider logic device concepts based on our previously proposed spintronics device element whose magnetization orientation is controlled by application of a bias voltage instead of a magnetic field. The basic building block is the voltage-controlled rotation (VCR) element that consists of a four-layer structure--two ferromagnetic layers separated by both nanometer-thick insulator and metallic spacer layers. The interlayer exchange coupling between the two ferromagnetic layers oscillates as a function of applied voltage. We illustrate transistorlike concepts and reprogrammable logic gates based on VCR elements. (c) 2000 American Institute of Physics.

You, Chun-Yeol [Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Bader, S. D. [Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

2000-05-01T23:59:59.000Z

433

Interphase power controller with voltage injection  

Science Conference Proceedings (OSTI)

This paper introduces a new family of Interphase Power Controllers (IPC) based on the principle of voltage injection commonly used in phase-shifting transformers (PST). The voltage injection IPC exhibits power (active and reactive) control characteristics similar to previously defined IPC's and retains their inherent qualities: passive control, short circuit limitation and voltage decoupling. It also provides more flexibility for the adjustment of the operating points. Two promising topologies are described in more detail. One of them offers the potential of retrofitting existing phase-shifting transformers into full-fledged IPC's.

Beauregard, F.; Brochu, J.; Morin, G.; Pelletier, P. (Centre d'Innovation sur le Transport d'Energie du Quebec, Varennes, Quebec (Canada))

1994-10-01T23:59:59.000Z

434

Performance of a voltage peak detection-based flickermeter  

Science Conference Proceedings (OSTI)

Voltage fluctuations and rapid voltage changes lead to lamps flickering and disturbance of visual perception may occur consequently. For evaluation of the flicker severity level by means of voltage measurement there was developed an instrument called ... Keywords: Matlab Simulink, flickermeter, interharmonics, performance analysis, voltage fluctuation, voltage peak detection

Jiri Drapela

2009-12-01T23:59:59.000Z

435

High concentration two-stage optics for parabolic trough solar collectors with tubular absorber and large rim angle  

SciTech Connect

A new two-stage optical design is proposed for parabolic trough solar collectors with tubular absorbers. It can boost the concentration ratio by a factor of 2.5 relative to the conventional design, while maintaining the large rim angles (i.e., low nominal f-numbers) that are desirable for practical and economical reasons. The second state involves asymmetric nonimaging concentrators of the CPC type, facing segments of the parabolic first stage. The second stage can be accommodated inside an evacuated receiver, allowing the use of first-surface silvered reflectors. The low heat loss of this design opens the possibility of producing steam at temperatures and pressures of conventional power plants, using only one-axis tracking. The improvement in conversion efficiency would be substantial.

Collares-Pereira, M. (Centro para a Conservacao de Energia, Amadora (Portugal)); Gordon, J.M. (Ben Gurion Univ. of the Negev, Beersheva (Israel)); Rabl, A. (Centre d'Energetique, Paris (France)); Winston, R. (Univ. of Chicago, IL (United States))

1991-01-01T23:59:59.000Z

436

High Bandwidth Differential Amplifier for Shock Experiments  

Science Conference Proceedings (OSTI)

We developed a high bandwidth differential amplifier for gas gun shock experiments/applications. The circuit has a bandwidth > 1 GHz, and is capable of measuring signals of ?1.5 V with a common mode rejection of 250 V. Conductivity measurements of gas gun targets are measured by flowing high currents through the targets. The voltage is measured across the target using a technique similar to a four-point probe. Because of the design of the current source and load, the target voltage is approximately 250 V relative to ground. Since the expected voltage change in the target is < 1 V, the differential amplifier must have a large common mode rejection. High pass filters suppress internal ringing of operational amplifiers. Results of bench tests are shown.

Ross, P. W., Tran, V., Chau, R.

2012-04-30T23:59:59.000Z

437

Demonstration and System Analysis of High Temperature Steam Electrolysis for Large-Scale Hydrogen Production Using SOFCs  

DOE Green Energy (OSTI)

At the Idaho National Engineering Laboratory, an integrated laboratory scale (ILS), 15 kW high-temperature electrolysis (HTE) facility has been developed under the U.S. Department of Energy Nuclear Hydrogen Initiative. Initial operation of this facility resulted in over 400 hours of operation with an average hydrogen production rate of approximately 0.9 Nm3/hr. The integrated laboratory scale facility is designed to address larger-scale issues such as thermal management (feed-stock heating, high-temperature gas handling), multiple-stack hot-zone design, multiple-stack electrical configurations, and other integral issues. Additionally, a reference process model of a commercial-scale high-temperature electrolysis plant for hydrogen production has been developed. The reference plant design is driven by a 600 megawatt thermal high-temperature helium-cooled reactor coupled to a direct Brayton power cycle. The electrolysis unit used to produce hydrogen consists of 4.01106 cells with a per-cell active area of 225 cm2. A nominal cell area-specific resistance, ASR, value of 0.4 Ohmcm2 with a current density of 0.25 A/cm2 was used, and isothermal boundary conditions were assumed. The overall system thermal-to-hydrogen production efficiency (based on the low heating value of the produced hydrogen) is 47.1% at a hydrogen production rate of 2.36 kg/s with the high-temperature helium-cooled reactor concept. This paper documents the initial operation of the ILS, with experimental details about heat-up, initial stack performance, as well as long-term operation and stack degradation. The paper will also present the optimized design for the reference nuclear-driven HTE hydrogen production plant which may be compared with other hydrogen production methods and power cycles to evaluate relative performance characteristics and plant economics.

Michael G. McKellar; James E. O'Brien; Carl M. Stoots; J. Stephen Herring

2008-07-01T23:59:59.000Z

438

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 +

439

Superconducting Low Voltage Direct Current (LVDC) Networks  

Science Conference Proceedings (OSTI)

A low voltage dc superconducting distribution network is a challenging future opportunity for power distribution. This report presents a scheme for a superconducting, parallel- connected, multiterminal dc transmission system.

1994-04-27T23:59:59.000Z

440

Assessment of Voltage Security Methods and Tools  

Science Conference Proceedings (OSTI)

To ensure voltage-secure operation of a power system, VAR control devices must be optimally placed and operated. This project assessed tools and methods that claim to help utilities meet these needs and recommended specific enhancements to these tools.

1995-10-26T23:59:59.000Z

Note: This page contains sample records for the topic "high voltage large" 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

High speed signal and data processing using very large scale integrated (VLSI)/VHSIC general purpose computer systems  

SciTech Connect

The combined requirements of size, weight, throughput, reliability, and testability imposed on signal and data processing systems by new electro-optical sensors cannot be met with conventional architectures or circuit technology. One solution to this problem is described by the authors. This solution is a result of five years of work done to date on the Modular Missile Borne Computer (MMBC) combined with the more recent very high speed integrated circuit (VHSIC) program. 12 references.

Ramseyer, R.; Johnson, M.; Thomas, J.

1982-01-01T23:59:59.000Z

442

Nano-Composite Dielectrics on Medium-Voltage Model Cables  

Science Conference Proceedings (OSTI)

EPRI early recognized the potential for nanotechnology in power distribution and started a program in 2003 to explore the possibilities of using the technology to enhance the properties of high-voltage (HV) cable dielectrics based on both polyethylene and on ethylene-propylene rubber. This research resulted in encouraging findings, particularly for a formulation based on functionalized silicon dioxide nanoparticles in a cross-linked polyethylene (XLPE) polymer. Following this success, EPRI entered into a...

2007-12-19T23:59:59.000Z

443

Research on high-efficiency, large-area, CuInSe{sub 2}-based thin- film modules. Annual subcontract report, 1 May 1992--15 Aug 1993  

DOE Green Energy (OSTI)

This report describes work to demonstrate 12.5% aperture efficient, large-area (3900-cm{sup 2}) encapsulated thin-film CuInSe{sub 2} (CIS) photovoltaic modules. Module design consists of 53 series-connected ZnO/CdS/CIS/Mo/glass cells fabricated on a 4141-cm{sup 2} (128.6 {times} 32.2 cm) glass substrate with a nominal aperture area of 3895 cm{sup 2} (127.3 {times} 30.6 cm). Four CIS modules were shipped to NREL under the terms of the subcontract. Phase 2 consisted of fabricating large-area (3900-cm{sup 2}) modules for high-performance module processing. The large-area parts proved to be cumbersome, and we decided to use smaller substrates (100 cm{sup 2}) to accelerate the progress in solving the types of technical challenges that were discovered in processing large-area parts, and then to apply these solutions to larger areas to meet the objectives of the investigation. Most critical issues determining module yield losses can be grouped into three major categories: (1) Uniformity and reproducibility of the absorber formation process dominates the fundamental performance of the material over a large area, (2) interaction of the substrate with the Mm requires appropriate selection criterial and preparation techniques for minimizing defects that lead to shunting and areas of poor photoresponse, and (3) performance losses near interconnects reduce module performance and can cause inadequate performance through module durability testing.

Knapp, K.E.; Gay, R.R. [Siemens Solar Industries, Camarillo, CA (United States)

1994-01-01T23:59:59.000Z

444

Spark gap with low breakdown voltage jitter  

SciTech Connect

Novel spark gap devices and electrodes are disclosed. The novel spark gap devices and electrodes are suitable for use in a variety of spark gap device applications. The shape of the electrodes gives rise to local field enhancements and reduces breakdown voltage jitter. Breakdown voltage jitter of approximately 5% has been measured in spark gaps according the invention. Novel electrode geometries and materials are disclosed.

Rohwein, Gerald J. (Albuquerque, NM); Roose, Lars D. (Albuquerque, NM)

1996-01-01T23:59:59.000Z

445

Voltage Control Optimization to Improve Transmission Efficiency  

Science Conference Proceedings (OSTI)

An optimal power flow solution is unique from a conventional power flow solution in that an objective function and user-specified constraints are enforced and satisfied to reach a valid solution. This report presents an analytical study on the optimization of power flow in order to minimize reactive power losses via the modification of generator voltage schedules and transmission switched shunt status. The study examines the potential benefits and applicability of near-real-time voltage control ...

2012-11-08T23:59:59.000Z

446

Power Quality Hotline Call-of-the-Month for August 2009: Voltage Harmonics, Part 1: Fundamentals  

Science Conference Proceedings (OSTI)

This Call of the Month discusses what harmonics are and how they're produced. Part 2 will address the equipment concerns related to the presence of high levels of harmonic distortion in a customer's service voltage.

2009-12-11T23:59:59.000Z

447

Fault-Delayed Voltage Recovery Control with Plug-In Hybrid Electric Vehicles  

Science Conference Proceedings (OSTI)

This paper presents an investigation into the impact that plug-in hybrid electric vehicles (PHEVs) could have to mitigate the effects of fault-delayed voltage recovery. The energy storage and conversion system in PHEVs, given potentially high levels ...

Curtis Roe; Yousef M. Al-Abdullah; Dhwanil Desai; George K. Stefopoulos; George J. Cokkinides; A. P. Meliopoulos

2010-01-01T23:59:59.000Z

448

Design of a low-voltage low-power dc-dc HF converter  

E-Print Network (OSTI)

Many portable electronic applications could benefit from a power converter able to achieve high efficiency across wide input and output voltage ranges at a small size. However, it is difficult for many conventional power ...

Hu, Jingying, Ph. D. Massachusetts Institute of Technology.

2008-01-01T23:59:59.000Z

449

System for increasing corona inception voltage of insulating oils  

DOE Patents (OSTI)

The Corona Inception Voltage of insulating oils is increased by repetitive cycles of prestressing the oil with a voltage greater than the corona inception voltage, and either simultaneously or serially removing byproducts of corona by evacuation and heating the oil.

Rohwein, Gerald J. (Albuquerque, NM)

1998-01-01T23:59:59.000Z

450

Voltage protection scheme for MG sets used to drive inductive energy storage systems  

DOE Green Energy (OSTI)

A recent tokamak proposal at ORNL called for MG (motor-generator) sets to drive the ohmic heating (OH) coil, which was to be subjected to 20 kV immediately after coil charge-up to initiate the experiment. Since most rotating machinery is inherently low voltage, including the machines available at ORNL, a mechanism was necessary to isolate the generators from the high voltage portions of the circuit before the appearance of this voltage. It is not the expected 20 kV at the coil that causes difficulty, because the main interrupting switch handles this. The voltage induced in the armature due to di/dt and the possibility of faults are the greatest causes for concern and are responsible for the complexity of the voltage protection scheme, which must accommodate any possible combination of fault time and location. Such a protection scheme is presented in this paper.

Campen, G.L.; Easter, R.B.

1977-01-01T23:59:59.000Z

451

A NOVEL LOW THERMAL BUDGET THIN-FILM POLYSILICON FABRICATION PROCESS FOR LARGE-AREA, HIGH-THROUGHPUT SOLAR CELL PRODUCTION  

DOE Green Energy (OSTI)

methods. The poly-Si solar cell structure and the performance have been examined. In principle, the new process is potentially applicable to produce large-area thin-film poly-Si solar cells at a high throughput and low cost. A critical issue in this process is to prevent the excessive dopant diffusion during crystallization. Process parameters and the cell structure have to be optimized to achieve the production goal.

Yue Kuo

2010-08-15T23:59:59.000Z

452

Ultra-low voltage resonant tunnelling diode electroabsorption modulator  

E-Print Network (OSTI)

Embedding a double barrier resonant tunnelling diode (RTD) in an unipolar InGaAlAs optical waveguide gives rise to a very low driving voltage electroabsorption modulator (EAM) at optical wavelengths around 1550 nm. The presence of the RTD within the waveguide core introduces high non-linearity and negative differential resistance in the current-voltage (I-V) characteristic of the waveguide. This makes the electric field distribution across the waveguide core strongly dependent on the bias voltage: when the current decreases from the peak to the valley there is an increase of the electric field across the depleted core. The electric field enhancement in the core-depleted layer causes the Franz-Keldysh absorption band-edge to red shift, which is responsible for the electroabsorption effect. High frequency ac signals as low as 100 mV can induce electric field high speed switching, producing substantial light modulation (up to 15 dB) at photon energies slightly lower than the waveguide core band-gap energy. The k...

Figueiredo, J M L; Stanley, C R

2002-01-01T23:59:59.000Z

453

Chemical Abundances in Twelve Red Giants of the Large Magellanic Cloud from High-Resolution Infrared Spectroscopy  

E-Print Network (OSTI)

High-resolution infrared spectra (R=50,000) have been obtained for twelve red-giant members of the LMC with the Gemini South 8.3-meter telescope plus Phoenix spectrometer. Quantitative chemical abundances of carbon-12, carbon-13, nitrogen-14, and oxygen-16 were derived from molecular lines of CO, CN, and OH, while sodium, scandium, titanium, and iron abundances were derived from neutral atomic lines. The LMC giants have masses from about 1 to 4 solar masses and span a metallicity range from [Fe/H]= -1.1 to -0.3. The program red giants all show evidence of first dredge-up mixing, with low 12C/13C ratios, and low 12C correlated with high 14N abundances. Comparisons of the oxygen-to-iron ratios in the LMC and the Galaxy indicate that the trend of [O/Fe] versus [Fe/H] in the LMC falls about 0.2 dex below the Galactic trend. Such an offset can be modeled as due to an overall lower rate of supernovae per unit mass in the LMC relative to the Galaxy, as well as a slightly lower ratio of supernovae of type II to supernovae of type Ia.

V. V. Smith; K. H. Hinkle; K. Cunha; B. Plez; D. L. Lambert; C. A. Pilachowski; B. Barbuy; J. Melendez; S. Balachandran; M. S. Bessell; D. P. Geisler; J. E. Hesser; C. Winge

2002-08-22T23:59:59.000Z

454

Operation of a large GEM-MSGC detector in a high intensity hadronic test beam using fully pipelined readout electronics  

E-Print Network (OSTI)

98-060 In a recent test beam experiment at PSI a new tracking device for very high particle fluxes consisting of a low gain micro strip gas chamber (MSGC) combined with a gas electron multiplier (GEM) foil has been run under beam conditions similar to those foreseen in the HERA-B experiment [1], where such devices are being installed for the inner tracker. They are also being evaluated for the LHCb experiment [2]. In both detectors very high, mainly hadronic particle densities (up to 10 4 mm -2 sec -1) are expected, while the momentum resolution of the magnetic spectrometers foreseen in the two experiments is limited by multiple scattering. Also photon conversions represent a significant background source and therefore a minimal thickness in terms of radiation length is important, while position resolution requirements are moderate (typically 300 mu m pitch is sufficient). This paper describes the detailed construction of this novel detector, the test beam configuration and some of the data taken using the fu...

Eisele, F; Straumann, U; Straumann, Ulrich

1998-01-01T23:59:59.000Z

455

Detection of ultra high energy neutrinos with an underwater very large volume array of acoustic sensors: A simulation study  

E-Print Network (OSTI)

This thesis investigates the detection of ultra high energy (E > 1 EeV) cosmic neutrinos using acoustic sensors immersed in water. The method is based on the thermoacoustic model describing the production of microsecond bipolar acoustic pulses by neutrino-induced particle cascades. These cascades locally heat the medium which leads to rapid expansion and a short sonic pulse detectable in water with hydrophones over distances of several kilometres. This makes acoustic detection an approach complementary to todays optical Cerenkov and radio Cerenkov detectors, and could help to reduce the respective systematic uncertainties. In this work a complete simulation / reconstruction chain for a submarine acoustic neutrino telescope is developed, and the sensitivity of such a detector to a diffuse flux of ultra highenergy cosmic neutrinos is estimated.

Timo Karg

2006-08-15T23:59:59.000Z

456

Appendix C: California ISO Real Time Voltage Security Assessment...  

NLE Websites -- All DOE Office Websites (Extended Search)

C: California ISO Real Time Voltage Security Assessment (VSA) Prototype Functional SpecificationsPrototype Development Title Appendix C: California ISO Real Time Voltage Security...

457

Appendix B: California ISO Real Time Voltage Security Assessment...  

NLE Websites -- All DOE Office Websites (Extended Search)

B: California ISO Real Time Voltage Security Assessment (VSA) Summary Report Title Appendix B: California ISO Real Time Voltage Security Assessment (VSA) Summary Report Publication...

458

Appendix A: California ISO Real Time Voltage Security Assessment...  

NLE Websites -- All DOE Office Websites (Extended Search)

A: California ISO Real Time Voltage Security Assessment (VSA) Project: Summary of Survey Results on Methodologies for use in Real-Time Voltage Security Assessment Title Appendix A:...

459

Green Island Power Authority Transmission Voltage Support System...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Green Island Power Authority Transmission Voltage Support System Project Green Island Power Authority Transmission Voltage Support System Project Power point presentation...

460

A Reconfigurable 8T Ultra-Dynamic Voltage Scalable (U-DVS) SRAM in 65 nm CMOS  

E-Print Network (OSTI)

In modern ICs, the trend of integrating more on-chip memories on a die has led SRAMs to account for a large fraction of total area and energy of a chip. Therefore, designing memories with dynamic voltage scaling (DVS) ...

Verma, Naveen

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461

The analysis and specification of large high-pressure, high-temperature valves for combustion turbine protection in second-generation PFB power plants: Topical report  

SciTech Connect

The purpose of this study was to provide a specification for the high-pressure/high-temperature valves for turbine overspeed protection in a commercial-scale second-generation pressurized fluidized bed combustion (PFBC) power plant. In the event of a loss of external (generator) load, the gas turbine rapidly accelerates from its normal operating speed. Protection from excessive overspeed can be maintained by actuation of fuel isolation and air bypass valves. A design specification for these valves was developed by analyses of the turbine/compressor interaction during a loss of load and analyses of pressure and flow transients during operation of the overspeed protection valves. The basis for these analyses was the Phase 1 plant conceptual design prepared in 1987.

1994-08-01T23:59:59.000Z

462

765kV Transmission line Voltage gradient  

E-Print Network (OSTI)

Corona ring Transmission lines Nowadays, due to the ever increasing energy consumption and power supply optimization, it is required to construct new power plants, substations and transmission lines. In Iran, also, because of increasing demand for electrical energy, for a significant power loss reduction in power transmission over long distances, and to construct high transmission lines that lead to reduction in the economic costs of transmission lines, the transmission lines must be considered at extra high voltage (EHV) levels. These EHV levels should be compared with the low voltage levels in order to extract the benefits. Therefore, in this paper, a review has been conducted on the types of 765 kV transmission lines used in different countries and a comparison between them and the low voltage levels have been performed. Accordingly, the advantages of EHV transmission lines are summarized. Finally, designing a line of 765 kV single-circuit with 6 conductors per bundle based on existing standards is presented.

unknown authors

2012-01-01T23:59:59.000Z

463

A Large-Area Cross-Correlation Study of High Galactic Latutude Soft and Hard X-ray Skies  

E-Print Network (OSTI)

We have made cross-correlation analyses of (2 -- 15 keV) HEAO A2 and 1 keV ROSAT PSPC All-Sky Survey maps over a selected area ($\\sim$ 4000 deg$^2$) with high galactic latitude (b>40 deg). We have calculated the correlations for the bright ROSAT sources and residual background separately with the \\HEAO A2 TOT (2 -- 10 keV) and HRD (5 -- 15 keV) maps. The amplitude of the bright \\ROSAT source -- A2 CCFs are consistent with expectations from model populations of AGNs and clusters of galaxies, which emit in both bands. However, the residual ROSAT background -- A2 CCFs amplitude at zero degree are about a factor of three larger than that expected from the model populations. Our soft-hard zero-lag and angular CCF results have been compared with the 1 keV auto-correlation function (ACF) found by Soltan et al. (1995) for the same ROSAT data. Their significant angular CCF at a scale of ACF has a hot plasma spectrum with kT\\sim 2 keV, contribution of this component is consistent with both our zero-lag CCF in excess of the population synthesis model prediction and the upper-limit to the angular CCF at \\theta \\sim 2.5 deg. On the other hand, if this component has a lower temperature or a steeper spectrum, a major modification to the population synthesis model and/or an introduction of new classes would be needed.

Takamitsu Miyaji; Guenther Hasinger; Roland Egger; Joachim Truemper; Michael J. Freyberg

1996-01-30T23:59:59.000Z

464

A capacitor-less low drop-out voltage regulator with fast transient response  

E-Print Network (OSTI)

Power management has had an ever increasing role in the present electronic industry. Battery powered and handheld applications require power management techniques to extend the life of the battery and consequently the operation life of the device. Most systems incorporate several voltage regulators which supply various subsystems and provide isolation among such subsystems. Low dropout (LDO) voltage regulators are generally used to supply low voltage, low noise analog circuitry. Each LDO regulator demands a large external capacitor, in the range of a few microfarads, to perform. These external capacitors occupy valuable board space, increase the IC pin count, and prohibit system-on-chip (SoC) solutions. The presented research provides a solution to the present bulky external capacitor LDO voltage regulators with a capacitor-less LDO architecture. The large external capacitor was completely removed and replaced with a reasonable 100pF internal output capacitor, allowing for greater power system integration for SoC applications. A new compensation scheme is presented that provides both a fast transient response and full range ac stability from a 0mA to 50mA load current. A 50mA, 2.8V, capacitor-less LDO voltage regulator was fabricated in a TSMC 0.35um CMOS technology, consuming only 65uA of ground current with a dropout voltage of 200mV. Experimental results show that the proposed capacitor-less LDO voltage regulator exceeds the current published works in both transient response and ac stability. The architecture is also less sensitive to process variation and loading conditions. Thus, the presented capacitor-less LDO voltage<