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

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

2

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

SciTech Connect (OSTI)

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

None

2012-01-25T23:59:59.000Z

3

An amorphous alloy core medium frequency magnetic-link for medium voltage photovoltaic inverters  

Science Journals Connector (OSTI)

The advanced magnetic materials with high saturation flux density and low specific core loss have led to the development of an efficient compact and lightweight multiple-input multiple-output medium frequency magnetic-link. It offers a new route to eliminate some critical limitations of recently proposed medium voltage photovoltaic inverters. In this paper a medium frequency magnetic-link is developed with Metglas amorphous alloy 2605S3A. The common magnetic-link generates isolated and balanced multiple DC supplies for all of the H-bridge inverter cells of the medium voltage inverter. The design and implementation of the prototype test platform and the experimental test results are analyzed and discussed. The medium frequency non-sinusoidal excitation electromagnetic characteristics of alloy 2605S3A are also compared with that of alloy 2605SA1. It is expected that the proposed new technology will have great potential for future renewable power generation systems and smart grid applications.

2014-01-01T23:59:59.000Z

4

Transient recovery voltage considerations in the application of medium voltage circuit breakers  

SciTech Connect (OSTI)

Medium Voltage Circuit Breakers can fail to interrupt 3-phase fault currents when power systems have Transient Recovery Voltage (TRV) characteristics which exceed the rating of the circuit breaker. This paper examines the application of 13.8kV generation and load switchgear for an oil refinery in which circuit parameters as originally designed would have exceeded the 13.8kV circuit breakers TRV ratings had corrective measures not been taken. This paper illustrates this case and discusses the basis of TRV, how TRV is assessed, and alternative actions taken to bring circuits to within the 13.8 kV circuit breaker ratings.

Swindler, D.L.; Schwartz, P.; Hamer, P.S.; Lambert, S.R.

1995-12-31T23:59:59.000Z

5

Electric Field Calculations on Dry-Type Medium Voltage Current Transformers.  

E-Print Network [OSTI]

??This research presents potential and electric field calculations on medium voltage (MV) epoxy insulated outdoor current transformers (CTs) using a numeri-cal calculation approach. Two designs… (more)

Lakshmichand Jain, Sandeep Kumar

2012-01-01T23:59:59.000Z

6

Optimal Placement of the Wind Generators in the Medium Voltage Power Grid  

Science Journals Connector (OSTI)

The minimization of power losses in the medium voltage (MV) grid requires adjustment of network of power sources. This problem is particularly important for renewable energy sources, for example for the farms of wind generators. Their placement and nominal ... Keywords: medium voltage power grid, wind generators, genetic algorithms, parallel processing

Andrzej Jordan; Ryszard Szczebiot; Carsten Maple; Slawomir Cieslik

2011-04-01T23:59:59.000Z

7

Application of evolutionary algorithms for the planning of urban distribution networks of medium voltage  

E-Print Network [OSTI]

Abstract—Currently, an important issue in power distribution is the need to optimize medium voltage (mv) networks serving urban areas. This paper shows how an evolutionary algorithm can be used as the basis for the type of efficient algorithm such optimization demands. The search for optimal network solution will be restricted to a graph defined from the urban map, so each graph branch represents a trench. The solution space (networks) is assumed with “loop feeder circuits”: networks with two electrical paths from the high voltage/medium voltage (hv/mv) substations to the customers. In the optimization process, the investment and loss load costs are considered taking into account the constraints of conductor capacities and voltage drop. The investment costs will take into account that some cables can be lying in the same trench. The process was applied for a Spanish city of 200 000 inhabitants. Index Terms—Evolutionary algorithm, medium voltage network planning, network design, urban distribution network. I.

unknown authors

2002-01-01T23:59:59.000Z

8

Analysis of asset health : an approach to monitoring and diagnostics for medium voltage circuit breakers  

E-Print Network [OSTI]

The Medium Voltage Electric Industry is a very conservative and risk adverse sector that has undergone very little change in the past 30 years when compared to other technologically dependent activities; this reality is ...

Corona, Erick (Erick Gustavo)

2013-01-01T23:59:59.000Z

9

A High Voltage Direct Current Generator  

Science Journals Connector (OSTI)

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

Richard E. Vollrath

1932-10-15T23:59:59.000Z

10

Summary of multiterminal high-voltage direct current transmission technology  

SciTech Connect (OSTI)

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

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

1984-05-01T23:59:59.000Z

11

Towards Decentralized Trading: A Topological Investigation of the Dutch Medium and Low Voltage Grids  

E-Print Network [OSTI]

The traditional Power Grid has been designed in a hierarchical fashion, with Energy pushed from the large scale production facilities towards the end users. But with the increasing availability of micro and medium scale generating facilities, the situation is changing. Many end users can now produce energy and share it over the Power Grid. Naturally, end users need to have incentives to do so and might want to be able to act in an open decentralized energy market. In the present work, we offer a novel analysis of the Medium and Low Voltage Power Grids of the North Netherlands using statistical tools from the Complex Network Analysis field. We use a weighted model based on actual Grid data and propose a set of statistical measures to evaluate the adequacy of the current infrastructure for a decentralized energy market. Further, we use the insight gained by the analysis to propose parameters that tie the statistical topological measures to economic factors that might influence the attractiveness to the end user...

Pagani, Giuliano Andrea

2011-01-01T23:59:59.000Z

12

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

SciTech Connect (OSTI)

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

Litzenberger, Wayne; Lava, Val

1994-08-01T23:59:59.000Z

13

Bi-directional power control system for voltage converter  

DOE Patents [OSTI]

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

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

1999-01-01T23:59:59.000Z

14

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

Science Journals Connector (OSTI)

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

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

2008-12-01T23:59:59.000Z

15

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

SciTech Connect (OSTI)

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

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

1996-12-31T23:59:59.000Z

16

Investigation into direct conversion with medium energy He-ion beams  

E-Print Network [OSTI]

INVESTIGATION INTO DIRECT ENERGY CONVERSION WITH MEDIUM ENERGY HELIUM-ION BEAMS A Thesis by AVERY ALLAN GUILD-BINGHAM Submitted to the Office of Graduate Studies of Texas A&M University in partial... fulfillment of the requirements for the degree of MASTER OF SCIENCE December 2004 Major Subject: Nuclear Engineering INVESTIGATION INTO DIRECT ENERGY CONVERSION WITH MEDIUM ENERGY HELIUM-ION BEAMS A Thesis...

Guild-Bingham, Avery A.

2005-02-17T23:59:59.000Z

17

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

Science Journals Connector (OSTI)

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

Mohammad Farshadnia; Seyed Abbas Taher

2014-01-01T23:59:59.000Z

18

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

E-Print Network [OSTI]

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

Pouwelse, Johan

19

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

SciTech Connect (OSTI)

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

None

2012-01-23T23:59:59.000Z

20

2.3-MW Medium-Voltage, Three-Level Wind Energy Inverter Applying a Unique Bus Structure and 4.5-kV Si/SiC Hybrid Isolated Power Modules: Preprint  

SciTech Connect (OSTI)

A high-efficiency, 2.3-MW, medium-voltage, three-level inverter utilizing 4.5-kV Si/SiC (silicon carbide) hybrid modules for wind energy applications is discussed. The inverter addresses recent trends in siting the inverter within the base of multimegawatt turbine towers. A simplified split, three-layer laminated bus structure that maintains low parasitic inductances is introduced along with a low-voltage, high-current test method for determining these inductances. Feed-thru bushings, edge fill methods, and other design features of the laminated bus structure provide voltage isolation that is consistent with the 10.4-kV module isolation levels. Inverter efficiency improvement is a result of the (essential) elimination of the reverse recovery charge present in 4.5-kV Si PIN diodes, which can produce a significant reduction in diode turn-off losses as well as insulated-gate bipolar transistor (IGBT) turn-on losses. The hybrid modules are supplied in industry-standard 140 mm x 130 mm and 190 mm x 130 mm packages to demonstrate direct module substitution into existing inverter designs. A focus on laminated bus/capacitor-bank/module subassembly level switching performance is presented.

Erdman, W.; Keller, J.; Grider, D.; VanBrunt, E.

2014-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "direct medium voltage" 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

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

Science Journals Connector (OSTI)

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

Mohammad Jafar Zandzadeh; Abolfazl Vahedi

2014-01-01T23:59:59.000Z

22

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

E-Print Network [OSTI]

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

Kimball, Jonathan W.

23

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

SciTech Connect (OSTI)

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

NONE

2005-07-01T23:59:59.000Z

24

A design for the interface between a battery storage and charging unit, and a medium voltage DC (MVDC) bus, as part of an integrated propulsion system (IPS) in the all electric ship (AES)  

Science Journals Connector (OSTI)

In this paper we present the design of a rechargeable battery storage device for use in an all-electric ship. The purpose of this device is to provide power of predictable quality to selected equipment. In addition a recharging unit is proposed for recharging ... Keywords: electric ship, energy storage, medium voltage DC (MVDC), pulse load

T. A. Trapp; P. Prempraneerach; C. Chryssostomidis; J. L. Kirtley, Jr.; G. E. Karniadakis

2011-06-01T23:59:59.000Z

25

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

SciTech Connect (OSTI)

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

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

1986-01-01T23:59:59.000Z

26

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

SciTech Connect (OSTI)

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

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

2014-10-15T23:59:59.000Z

27

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

SciTech Connect (OSTI)

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

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

2013-07-01T23:59:59.000Z

28

Analysis of a direct energy conversion system using medium energy helium ions  

E-Print Network [OSTI]

in Direct Energy Conversion Fission Electric Cells", Transactions of the American Nuclear Society, 91, 2(2004). 2) G. H. Miley, Fusion Energy Conversion, American Nuclear Society, Hinsdale, IL, 77 (1976). 3) G. I. Budker, ?Thermonuclear Reactions... in Direct Energy Conversion Fission Electric Cells", Transactions of the American Nuclear Society, 91, 2(2004). 2) G. H. Miley, Fusion Energy Conversion, American Nuclear Society, Hinsdale, IL, 77 (1976). 3) G. I. Budker, ?Thermonuclear Reactions...

Carter, Jesse James

2006-08-16T23:59:59.000Z

29

ABBGroup-1-High voltage lab  

E-Print Network [OSTI]

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

Basse, Nils Plesner

30

A NEW METHOD TO DIRECTLY MEASURE THE JEANS SCALE OF THE INTERGALACTIC MEDIUM USING CLOSE QUASAR PAIRS  

SciTech Connect (OSTI)

Although the baryons in the intergalactic medium (IGM) trace dark matter fluctuations on megaparsec scales, on smaller scales ?100 kpc, fluctuations are suppressed because the finite temperature gas is pressure supported against gravity, analogous to the classical Jeans argument. This Jeans filtering scale, which quantifies the small-scale structure of the IGM, has fundamental cosmological implications. First, it provides a thermal record of heat injected by ultraviolet photons during cosmic reionization events, and thus constrains the thermal and reionization history of the universe. Second, the Jeans scale determines the clumpiness of the IGM, a critical ingredient in models of cosmic reionization. Third, it sets the minimum mass scale for gravitational collapse from the IGM, and hence plays a pivotal role in galaxy formation. Unfortunately, it is extremely challenging to measure the Jeans scale via the standard technique of analyzing purely longitudinal Ly? forest spectra, because the thermal Doppler broadening of absorption lines along the line-of-sight, is highly degenerate with Jeans smoothing. In this work, we show that the Jeans filtering scale can be directly measured by characterizing the coherence of correlated Ly? forest absorption in close quasar pairs, with separations small enough ?100 kpc to resolve it. We present a novel technique for this purpose, based on the probability density function (PDF) of phase angle differences of homologous longitudinal Fourier modes in close quasar pair spectra. A Bayesian formalism is introduced based on the phase angle PDF, and Markov Chain Monte Carlo techniques are used to characterize the precision of a hypothetical Jeans scale measurement, and explore degeneracies with other thermal parameters governing the IGM. A semi-analytical model of the Ly? forest is used to generate a large grid (500) of thermal models from a dark matter only simulation. Our full parameter study indicates that a realistic sample of only 20 close quasar pair spectra can pinpoint the Jeans scale to ? 5% precision, independent of the amplitude T{sub 0} and slope ? of the temperature-density relation of the IGM T=T{sub 0}(?/ ?-bar ){sup ?-1}. This exquisite sensitivity arises because even long-wavelength one-dimensional Fourier modes ?10 Mpc, i.e., two orders of magnitude larger than the Jeans scale, are nevertheless dominated by projected small-scale three-dimensional (3D) power. Hence phase angle differences between all modes of quasar pair spectra actually probe the shape of the 3D power spectrum on scales comparable to the pair separation. We show that this new method for measuring the Jeans scale is unbiased and is insensitive to a battery of systematics that typically plague Ly? forest measurements, such as continuum fitting errors, imprecise knowledge of the noise level and/or spectral resolution, and metal-line absorption.

Rorai, Alberto; Hennawi, Joseph F. [Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg (Germany); White, Martin [Department of Astronomy, University of California at Berkeley, 601 Campbell Hall, Berkeley, CA 94720-3411 (United States)

2013-10-01T23:59:59.000Z

31

High-voltage engineering  

E-Print Network [OSTI]

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

Gaxiola, E

2006-01-01T23:59:59.000Z

32

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

SciTech Connect (OSTI)

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

Not Available

1988-04-01T23:59:59.000Z

33

Centralized wind power plant voltage control with optimal power flow algorithm.  

E-Print Network [OSTI]

??This thesis presents a method of controlling the reactive power injected into a medium-voltage collection system by multiple wind turbine generators such that the voltage… (more)

Kline, Jared Andrew

2011-01-01T23:59:59.000Z

34

On the Statistical Physics of Directed Polymers in a Random Medium and Their Relation to Tree Codes  

E-Print Network [OSTI]

Terms: directed polymer, Cayley tree, free energy, partition function, tree coding, rate to the distortion of the tree code) of this walk is the sum of energies along the bonds visited. For a given energy of a typical realization of the system. For the case where the walks are defined on a tree (from

Merhav, Neri

35

High-pressure late cycle direct injection of natural gas in a rail medium speed diesel engine  

SciTech Connect (OSTI)

The performance of an Electro-Motive Division (EMD) 567B, two-cylinder locomotive research engine, when operated on high-pressure/late-cycle injection of natural gas, is presented in this paper. A redesign and fabrication of the fuel system was undertaken to facilitate the consumption of natural gas. A small percentage of No.2 diesel fuel (DF-2) was used to ignite the natural gas. Engine performance, while running natural gas, resulted in matching rated speed and power with slightly lower thermal efficiency. Full power was achieved with a ratio of 99 percent natural gas and 1 percent diesel fuel. However, at high natural gas to diesel fuel ratios, audible knock was detected. The primary objective of the project was to establish technical feasibility of, and basic technology for, operating medium-speed rail diesel engines on high-pressure natural gas. Secondary objectives were to attain adequate engine performance levels for rail application, develop a system oriented toward retrofit of in-service locomotives, and realize any potential improvements in thermal efficiency due to use of the high-pressure/late-cycle approach.

Wakenell, J.F.; O'Neal, G.B.; Baker, Q.A.

1987-01-01T23:59:59.000Z

36

ABBGroup-1-High voltage lab  

E-Print Network [OSTI]

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

Basse, Nils Plesner

37

Direct  

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

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

38

Ignition distributor voltage generator  

SciTech Connect (OSTI)

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

Boyer, J.A.

1986-11-04T23:59:59.000Z

39

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

E-Print Network [OSTI]

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

40

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

Note: This page contains sample records for the topic "direct medium voltage" 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

The Matrix Converter Drive Performance Under Abnormal Input Voltage Conditions  

E-Print Network [OSTI]

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

Hava, Ahmet

42

Voltage stabilization system in traction substation of urban electric transport  

Science Journals Connector (OSTI)

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

S. V. Shapiro; S. F. Muftiev

2011-02-01T23:59:59.000Z

43

Liquid chromatographic extraction medium  

DOE Patents [OSTI]

A method and apparatus are disclosed for extracting strontium and technetium values from biological, industrial and environmental sample solutions using a chromatographic column. An extractant medium for the column is prepared by generating a solution of a diluent containing a Crown ether and dispersing the solution on a resin substrate material. The sample solution is highly acidic and is introduced directed to the chromatographic column and strontium or technetium is eluted using deionized water. 1 fig.

Horwitz, E.P.; Dietz, M.L.

1994-09-13T23:59:59.000Z

44

Liquid chromatographic extraction medium  

DOE Patents [OSTI]

A method and apparatus for extracting strontium and technetium values from biological, industrial and environmental sample solutions using a chromatographic column is described. An extractant medium for the column is prepared by generating a solution of a diluent containing a Crown ether and dispersing the solution on a resin substrate material. The sample solution is highly acidic and is introduced directed to the chromatographic column and strontium or technetium is eluted using deionized water.

Horwitz, E. Philip (Naperville, IL); Dietz, Mark L. (Evanston, IL)

1994-01-01T23:59:59.000Z

45

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

46

Constant voltage electro-slag remelting control  

DOE Patents [OSTI]

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

Schlienger, M.E.

1996-10-22T23:59:59.000Z

47

Constant voltage ultracapacitor  

Science Journals Connector (OSTI)

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

Ezzat G. Bakhoum

2012-01-01T23:59:59.000Z

48

Voltage balanced multilevel voltage source converter system  

DOE Patents [OSTI]

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

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

1997-01-01T23:59:59.000Z

49

Voltage balanced multilevel voltage source converter system  

DOE Patents [OSTI]

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

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

1997-07-01T23:59:59.000Z

50

Substation voltage upgrading  

SciTech Connect (OSTI)

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

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

1989-08-01T23:59:59.000Z

51

Electro-optical voltage sensor head  

DOE Patents [OSTI]

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

Woods, Gregory K. (Idaho Falls, ID)

1998-01-01T23:59:59.000Z

52

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

53

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

54

High voltage DC power supply  

DOE Patents [OSTI]

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

Droege, Thomas F. (Batavia, IL)

1989-01-01T23:59:59.000Z

55

Low-voltage gyrotrons  

SciTech Connect (OSTI)

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

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

2013-03-15T23:59:59.000Z

56

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

57

Measurement of high voltage using Rutherford backscattering spectrometry  

E-Print Network [OSTI]

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

Abrego, Celestino Pete

2007-04-25T23:59:59.000Z

58

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

DOE Patents [OSTI]

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

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

1999-01-01T23:59:59.000Z

59

Design and applications of a flicker voltage generator  

SciTech Connect (OSTI)

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

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

1995-12-31T23:59:59.000Z

60

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

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


61

Charge-pump voltage converter  

DOE Patents [OSTI]

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

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

2009-11-03T23:59:59.000Z

62

Substation voltage upgrading  

SciTech Connect (OSTI)

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

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

1992-04-01T23:59:59.000Z

63

Temperature controlled high voltage regulator  

DOE Patents [OSTI]

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

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

2004-04-20T23:59:59.000Z

64

Experiment Hazard Class 13.0 - High Voltage  

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

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

65

Charmonium in Hot Medium  

E-Print Network [OSTI]

. The momentum dependence of the charmonium dissociation rate is worked out. The dominant process for in-medium charmonium regeneration is found to be a 3-to-2 process. Its corresponding regeneration rates from different input charmquark momentum spectra...

Zhao, Xingbo

2012-02-14T23:59:59.000Z

66

Amorphous Medium Language  

E-Print Network [OSTI]

Programming reliable behavior on a large mesh network composed of unreliable parts is difficult. Amorphous Medium Language addresses this problem by abstracting robustness and networking issues away from the programmer via ...

Beal, Jacob

67

Low voltage nonprimary explosive detonator  

DOE Patents [OSTI]

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

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

1982-01-01T23:59:59.000Z

68

Nickel-hydrogen voltage-efficiency model  

SciTech Connect (OSTI)

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

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

1996-12-31T23:59:59.000Z

69

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.

70

Saving Megawatts with Voltage Optimization  

E-Print Network [OSTI]

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

Wilson, T.; Bell, D.

2010-01-01T23:59:59.000Z

71

Voltage, energy and power in electric circuits  

E-Print Network [OSTI]

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

Berzins, M.

72

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

SciTech Connect (OSTI)

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

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

2011-01-01T23:59:59.000Z

73

Ancillary service details: Voltage control  

SciTech Connect (OSTI)

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

Kirby, B.; Hirst, E.

1997-12-01T23:59:59.000Z

74

High-Voltage Test Laboratories  

Science Journals Connector (OSTI)

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

Wolfgang Hauschild; Eberhard Lemke

2014-01-01T23:59:59.000Z

75

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

Science Journals Connector (OSTI)

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

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

2007-06-01T23:59:59.000Z

76

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

E-Print Network [OSTI]

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

Lanterman, Aaron

77

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

E-Print Network [OSTI]

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

Cañizares, Claudio A.

78

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

E-Print Network [OSTI]

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

Dimarogonas, Dimos

79

Current vs. Voltage Feedback Amplifiers  

E-Print Network [OSTI]

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

Lanterman, Aaron

80

Modulated voltage metastable ionization detector  

SciTech Connect (OSTI)

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

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

1985-08-27T23:59:59.000Z

Note: This page contains sample records for the topic "direct medium voltage" 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

High-voltage direct current handbook: First edition  

SciTech Connect (OSTI)

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

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

1994-12-31T23:59:59.000Z

82

Low voltage operation of plasma focus  

Science Journals Connector (OSTI)

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

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

2010-01-01T23:59:59.000Z

83

A theoretical study of the incandescent filament lamp performance under voltage flicker  

SciTech Connect (OSTI)

Incandescent filament lamp flicker, produced by voltage fluctuation, is a power quality problem that caused engineering concern since the onset of electrical illumination technology. The flicker phenomenon was analyzed and explained in early studies. Standards dealing with acceptable flicker levels are well known, nevertheless, today the discussion about flicker continues to be a top priority topic due to the fact that steady-state and transient voltage waveform distortion is a growing problem in low and medium voltage systems. In many situations voltage flicker is caused by subharmonics and interharmonics of voltage. Cycloconverters, welders and arc furnaces, eccentrically operating tools and integral cycle controlled power equipment are notorious for producing voltage flicker. The goal of this paper is to provide solid mathematical basis for the analytical modeling of incandescent filament lamp flicker when the voltage is nonsinusoidal. A mathematical model that enables the evaluation of the luminous flux modulation caused by noninteger harmonics (subharmonics and interharmonics) is presented. Three situations are detailed: square-wave voltage modulation, sinusoidal modulation and the case of noninteger harmonics with nearly contiguous frequencies.

Peretto, L. [Univ. of Bologna (Italy)] [Univ. of Bologna (Italy); Emanuel, A.E. [Worcester Polytechnic Inst., MA (United States)] [Worcester Polytechnic Inst., MA (United States)

1997-01-01T23:59:59.000Z

84

High voltage stability performance of a gamma ray detection device  

SciTech Connect (OSTI)

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

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

2014-02-12T23:59:59.000Z

85

Automatic Voltage Control of Electrical Systems  

Science Journals Connector (OSTI)

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

1934-01-20T23:59:59.000Z

86

Implications of Pulser Voltage Ripple  

SciTech Connect (OSTI)

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

Barnard, J J

2011-12-21T23:59:59.000Z

87

Onset voltage of corona on coated conductors  

SciTech Connect (OSTI)

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

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

1995-12-31T23:59:59.000Z

88

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

Science Journals Connector (OSTI)

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

H. R. Pota

2013-01-01T23:59:59.000Z

89

Fiber optic current monitor for high-voltage applications  

DOE Patents [OSTI]

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

Renda, George F. (Plainsboro, NJ)

1992-01-01T23:59:59.000Z

90

CMVRTC: Medium Truck Duty Cycle  

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

medium truck duty cycle (MTdc) project medium truck duty cycle (MTdc) project OVERVIEW The Medium Truck Duty Cycle (MTDC) project involves efforts to collect, analyze and archive data related to medium-truck operations in real-world driving environments. Such data and information will be useful to support technology evaluation efforts and to provide a means of accounting for real-world driving performance within medium-class truck analyses. The project involves private industry partners from various truck vocations. The MTDC project is unique in that there currently does not exist a national database of characteristic duty cycles for medium trucks. This project involves the collection of data from multiple vocations (four vocations) and multiple vehicles within these vocations (three vehicles per

91

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

92

Wind Power Plant Voltage Stability Evaluation: Preprint  

SciTech Connect (OSTI)

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

Muljadi, E.; Zhang, Y. C.

2014-09-01T23:59:59.000Z

93

High voltage load resistor array  

DOE Patents [OSTI]

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

Lehmann, Monty Ray (Smithfield, VA)

2005-01-18T23:59:59.000Z

94

Medium Truck Duty Cycle (MTDC)  

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

Routes Data Acquisition System Setup Routes Data Acquisition System Setup Medium Truck Duty Cycle (MTDC) Objective This Department of Energy project focuses on the collection and analysis medium truck (Class-6 and -7) duty cycle data from real-world operations. Analysis of this data will provide information pertaining to the fuel efficiencies and performance of medium trucks in several vocations. Outcomes Rich source of data and information that can contribute to the development of new tools Sound basis upon which DOE can make technology investment decisions A national archive of real-world-based medium-truck operational data that will support medium-duty vehicle energy efficiency research Collected Data Speed & Acceleration Fuel Consumption GPS Location Road Grade

95

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

SciTech Connect (OSTI)

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

Wohlgemuth, J.

2013-05-01T23:59:59.000Z

96

High Voltage Electrolyte for Lithium Batteries  

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

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

97

Optimal Placement of Wind Generators in Medium Voltage Power Grids -- Investigations of Genetic Algorithm  

Science Journals Connector (OSTI)

The paper presents investigations of a genetic algorithm for computations of power losses in the MV power grid. In this case, the vector of start population PO0 and mutation likelihood was investigated. Diagrams of power losses in the grid dependent ... Keywords: genetic algorithm, wind generators, power grid, parallel processing, MPI

Andrzej Jordan; Carsten Maple; Ryszard Szczebiot; Lukasz Swierczewski

2011-04-01T23:59:59.000Z

98

Medium Voltage Overhead Power-line Broadband Communications; Transmission Capacity and Electromagnetic Interference  

E-Print Network [OSTI]

and Electromagnetic Interference P. Amirshahi and M. Kavehrad (FIEEE) The Pennsylvania State University, Department distribution networks for broadband power-line communications applications. Electromagnetic interference

Kavehrad, Mohsen

99

Performance of reduced wall EPR insulated medium voltage power cables. Part 2: Mechanical characteristics  

SciTech Connect (OSTI)

For the replacement of paper insulated lead covered cables (PILC) reduced insulation wall designs have been developed. They provide a reliable lower diameter cable design for installation in existing PILC conduits. Representing Part 2 of the investigation, this paper presents the results of mechanical testing conducted on both reduced and full wall EPR insulated cables. Both jacketed and non-jacketed cable designs have been subjected to mechanical pulling forces which greatly exceed recommended industry limitations, followed by electrical testing to ascertain cable performance. The results of this study conclude that reduced wall EPR insulated cables can safely withstand the same pulling forces as recommended for conventional walls and can be designed for installation under the same pulling limitations.

Wen, Y.; Cinquemani, P.L. [Pirelli Cable Corp., Lexington, SC (United States)

1997-04-01T23:59:59.000Z

100

Performance of reduced wall EPR insulated medium voltage power cables. Pat 1: Electrical characteristics  

SciTech Connect (OSTI)

Paper insulated lead covered cables (PILC) have had a long and successful heritage. After almost 100 years, this design of cable is still in operation and continues to be manufactured. However, utilities are now looking for a reliable replacement for PILC cables. This is due to two primary reasons: (1) difficulty in installing and maintaining this type of cable and (2) increasing pressure to replace these cables due to environmental concerns. To date diameter limitations of conventional extruded dielectric cables has impeded their replacement in existing PILC conduits. This paper describes a study for the evaluation for reliably reducing the insulation thickness to achieve a lower diameter cable to effectively replace PILC cable in existing conduits. Part 1 of the investigation reviews the theory of insulation wall determination and the test program carried out to evaluate electrical performance of reduced wall EPR cables. Additionally, cable design concepts and constructions are discussed. In Part 2 the mechanical performance on conventional and reduced wall EPR insulated cables are evaluated. This is reported in a separate paper.

Cinquemani, P.L.; Wen, Y.; Kuchta, F.L.; Doench, C. [Pirelli Cable Corp., Lexington, SC (United States)] [Pirelli Cable Corp., Lexington, SC (United States)

1997-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "direct medium voltage" 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

Abb Inc. medium-voltage products' supply chain analysis, including inventory, supplier scorecard, and risk assessments  

E-Print Network [OSTI]

In conformance with ABB's process excellence plan, this thesis study was undertaken to support improvements in on-time delivery of components, decreased order cycles, and reduced inventory levels for ADVAC (spring-mechan ...

Gaskins, Tamboura E. (Tamboura Elyse)

2006-01-01T23:59:59.000Z

102

Modeling evaporation from porous medium influenced by turbulent free flow Thomas Fetzer  

E-Print Network [OSTI]

toolbox freeflow (1p2c) direct numerical simulation Reynolds-averaged- Navier-Stokes (RANS) Stokes flow medium (2p2c) direct numerical simulation pore network modeling representative elementary volume (REV as a one-phase, two-component system (1p2c), the porous medium as a two-phase, two-component system (2p2c

Cirpka, Olaf Arie

103

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

Science Journals Connector (OSTI)

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

Rishabh Dev Shukla; Ramesh Kumar Tripathi

2014-01-01T23:59:59.000Z

104

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

105

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

DOE Patents [OSTI]

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

Weiss, Jonathan D. (Albuquerque, NM)

1997-01-01T23:59:59.000Z

106

Analysis of Lightning-induced Voltages in Overhead Transmission Lines  

Science Journals Connector (OSTI)

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

Mostefa. Boumaiza; Djamel. Labed

2014-01-01T23:59:59.000Z

107

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

E-Print Network [OSTI]

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

LaMeres, Brock J.

108

Development of High Voltage Electron Microscope  

Science Journals Connector (OSTI)

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

Shinjiro KATAGIRI; Hirokazu KIMURA; Susumu OZASA; Kazumi SHIRAISHI

1969-01-01T23:59:59.000Z

109

Voltage regulation in linear induction accelerators  

DOE Patents [OSTI]

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

Parsons, William M. (Santa Fe, NM)

1992-01-01T23:59:59.000Z

110

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

111

Limitations of High-Voltage Insulation  

Science Journals Connector (OSTI)

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

1938-01-08T23:59:59.000Z

112

NREL: Measurements and Characterization - Current Versus Voltage  

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

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

113

High Voltage Safety Act | Department of Energy  

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

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

114

Non-contact current and voltage sensor  

DOE Patents [OSTI]

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

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

2014-03-25T23:59:59.000Z

115

Patch nearfield acoustic holography in a moving medium  

Science Journals Connector (OSTI)

Abstract To realize the accurate reconstruction of sound field in a moving medium under the condition of limited holographic aperture, a patch nearfield acoustic holography (NAH) in a moving medium is proposed. The proposed method not only reduces the influence caused by the limited aperture effects through sound field extrapolation, but also perfectly suits for sound field reconstruction in a moving medium by improving the shape of the modified Tikhonov regularization filter and the noise estimation method in accordance with flow effects. In the method, two cases that the flow direction is parallel to and perpendicular to the hologram surface are considered. Especially in the perpendicular case, the expression of the wavenumber component in the z direction is improved to make the proposed method suitable for the moving medium at a high Mach number. Simulations are investigated to examine the performance of the proposed method and show its advantages by comparing with NAH in a moving medium and the conventional patch NAH. It is found that, the proposed method is effective and robust at different flow velocities of the medium and different frequencies of the sound source.

Bi-Chun Dong; Chuan-Xing Bi; Xiao-Zheng Zhang; Yong-Bin Zhang

2014-01-01T23:59:59.000Z

116

High-voltage R-F feedthrough bushing  

DOE Patents [OSTI]

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

Grotz, G.F.

1982-09-03T23:59:59.000Z

117

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

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

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

118

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 +

119

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

120

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

Note: This page contains sample records for the topic "direct medium voltage" 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

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

122

Modular high voltage power supply for chemical analysis  

DOE Patents [OSTI]

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

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

2010-05-04T23:59:59.000Z

123

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

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

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

124

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

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

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

125

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

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

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

126

Cathode Synthesis and Voltage Fade: Designed Solutions Based...  

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

Cathode Synthesis and Voltage Fade: Designed Solutions Based on Theory Cathode Synthesis and Voltage Fade: Designed Solutions Based on Theory 2013 DOE Hydrogen and Fuel Cells...

127

Optimal Voltage Control of the Southern Norwegian Power Grid.  

E-Print Network [OSTI]

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

Hannisdal, Erik Lundegaard

2011-01-01T23:59:59.000Z

128

Addressing the Voltage Fade Issue with Lithium-Manganese-Rich...  

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

Addressing the Voltage Fade Issue with Lithium-Manganese-Rich Oxide Cathode Materials Addressing the Voltage Fade Issue with Lithium-Manganese-Rich Oxide Cathode Materials 2013 DOE...

129

High voltage overhead long transmission line design and fault analysis.  

E-Print Network [OSTI]

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

Elzain, Mohamed Ali

2011-01-01T23:59:59.000Z

130

Distribution System Voltage Performance Analysis for High-Penetration Photovoltaics  

SciTech Connect (OSTI)

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

Liu, E.; Bebic, J.

2008-02-01T23:59:59.000Z

131

Physical simulation study of dynamic voltage instability  

SciTech Connect (OSTI)

This paper presents a physical simulation of the dynamic behavior of voltage instability in an interconnected multimachine environment. The dynamic evolving process leading to eventual voltage collapse, the scenario of the progressive reactive support reduction resulting from the MXL protection relays, the OLTC operation, and the effect of switched-in capacitor banks are examined using physical facilities in the laboratory. The physical simulation results are also compared with digital simulation results. This physical investigation provides a reliable foundation for the effective development of assessment approaches and countermeasures.

Tso, S.K.; Zhu, T.X. [Univ. of Hong Kong (Hong Kong); Zeng, Q.Y. [Electric Power Research Inst., Beijing (China); Lo, K.L. [Univ. of Strathclyde, Glasgow (United Kingdom). Dept. of Electrical and Electrical Engineering

1995-12-31T23:59:59.000Z

132

Distributed voltage control strategy for LV networks with inverter-interfaced generators  

Science Journals Connector (OSTI)

Abstract Low voltage distribution networks are characterized by an ever growing diffusion of single and three phase distributed generators whose unregulated operation may deplete the power quality levels, in particular as regard voltage profiles and unbalances. This issue is at present under discussion by several national and international standardization bodies and the general trend is to require, for the new connections of generators to medium and low voltage grids, their participation to the reactive power network management. In this paper a novel strategy proposes to control the network voltage unbalance suitably for coordinating single and three-phase inverter interfaced embedded generators, concurrently with a local volt/var regulation action as foreseen by the new grid connection requirements. Simulations conducted on case study network representing a typical Italian 4-wire LV distribution system under different load/generation conditions, demonstrate that the coordinated action of single-phase and three-phase inverters may considerably reduce the degree of unbalance thus improving the network power quality levels.

R. Caldon; M. Coppo; R. Turri

2014-01-01T23:59:59.000Z

133

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

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

134

Electro-optic high voltage sensor  

DOE Patents [OSTI]

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

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

2002-01-01T23:59:59.000Z

135

Distribution System Voltage Regulation by Distributed Energy Resources  

SciTech Connect (OSTI)

This paper proposes a control method to regulate voltages in 3 phase unbalanced electrical distribution systems. A constrained optimization problem to minimize voltage deviations and maximize distributed energy resource (DER) active power output is solved by harmony search algorithm. IEEE 13 Bus Distribution Test System was modified to test three different cases: a) only voltage regulator controlled system b) only DER controlled system and c) both voltage regulator and DER controlled system. The simulation results show that systems with both voltage regulators and DER control provide better voltage profile.

Ceylan, Oguzhan [ORNL; Liu, Guodong [ORNL; Xu, Yan [ORNL; Tomsovic, Kevin [University of Tennessee, Knoxville (UTK)

2014-01-01T23:59:59.000Z

136

Four Phase Switched Reluctance Motor Direct Torque Control  

Science Journals Connector (OSTI)

The three-phase switched reluctance motor direct torque control method mostly is a simple transplantation of the three-phase AC asynchronous motor direct torque control method, not suitable for arbitrary-phase switched reluctance motor. In this paper, ... Keywords: SRM, Direct torque control, Flux vector, Voltage vector, Switched rule

Wang Mianhua

2011-01-01T23:59:59.000Z

137

Sacramento Area Voltage Support Environmental Impact Statement  

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

E E R R A N E V A D A R E G I O N Sacramento Area Voltage Support DRAFT ENVIRONMENTAL IMPACT STATEMENT DRAFT ENVIRONMENTAL IMPACT STATEMENT DOE/EIS-0323 NOVEMBER 2002 COVER SHEET Title: Sacramento Area Voltage Support Draft Environmental Impact Statement (EIS) Lead Agency: Western Area Power Administration (Western) Location: Alameda, Contra Costa, Placer, Sacramento, San Joaquin, and Sutter Counties, State of California. EIS Number: DOE/EIS-0323 Contact: Ms. Loreen McMahon, Environmental Project Manager Western Area Power Administration Sierra Nevada Region 114 Parkshore Drive Folsom, CA 95630 (916) 353-4460 (916) 985-1936 fax email: mcmahon@wapa.gov Website: Information is also available on our website: www.wapa.gov Hotline: 1-877-913-4440 (toll-free) Abstract The Western Area Power Administration's Central Valley Project transmission system forms an integral part of

138

High voltage electric substation performance in earthquakes  

SciTech Connect (OSTI)

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

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

1995-12-31T23:59:59.000Z

139

Superconducting Fault Current Limiter for Transmission Voltage  

Science Journals Connector (OSTI)

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

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

2012-01-01T23:59:59.000Z

140

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

Note: This page contains sample records for the topic "direct medium voltage" 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

Power-One produces the industry's broadest selection of linear power supplies with output voltages from 5 volts through 250 volts. Rugged  

E-Print Network [OSTI]

-A 5V @ 9A (Note 1,5) N 5V HD5-12/OVP-A 5V @ 12A (Note 1,5) D HE5-18/OVP-A 5V @ 18A (Note 1,5) E F5 regulatory standards, and is CE Marked to the Low Voltage Directive (LVD). INTERNATIONAL SERIES LINEARS marked to Low Voltage Directive · 100% Burn-In · 2 Year Warranty · Overvoltage Protection (OVP) Standard

Berns, Hans-Gerd

142

Low Voltage White Phosphorescent OLED Achievements  

Broader source: Energy.gov [DOE]

Universal Display Corporation (UDC) and its research partners at Princeton University and the University of Southern California have succeeded in developing a white phosphorescent OLED (PHOLED™) that achieved a record efficiency of 20 lumens per watt. This achievement is the result of the team's collaborative efforts to increase the efficiency of PHOLED lighting by focusing on two critical factors: lowering the drive voltages and increasing the amount of light extracted.

143

Classification of Voltage Sags Based on MPCA Models  

Science Journals Connector (OSTI)

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

Abbas Khosravi; Joaquim Melendez; Joan Colomer

2007-06-01T23:59:59.000Z

144

A BIST Technique for RF Voltage-Controlled Oscillators  

Science Journals Connector (OSTI)

A built-in self-test (BIST) architecture is proposed for voltage-controlled oscillators (VCO) operating at multigigahertz frequencies. By utilizing a frequency divider and a frequency-to-voltage converter (FVC), the output frequency and tuning range ...

Hsieh-Hung Hsieh; Yen-Chih Huang; Liang-Hung Lu; Guo-Wei Huang

2007-10-01T23:59:59.000Z

145

Low voltage amplifier architecture for high speed switched capacitor circuits  

E-Print Network [OSTI]

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

Shankar, Asit

2012-06-07T23:59:59.000Z

146

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

147

Analysis and design of an electronic voltage ratchet  

E-Print Network [OSTI]

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

Menendez, Jorge Carlos

2012-06-07T23:59:59.000Z

148

LM2907LM2917FrequencytoVoltageConverter February 1995  

E-Print Network [OSTI]

TL H 7942 LM2907LM2917FrequencytoVoltageConverter February 1995 LM2907 LM2917 Frequency to Voltage Converter General Description The LM2907 LM2917 series are monolithic frequency to voltage converters doubling for low ripple full input protection in two versions (LM2907-8 LM2917-8) and its output swings

Wedeward, Kevin

149

Low voltage vertical recording preamplifier for hard disk drives  

E-Print Network [OSTI]

. . . . . . . . . . . . . . . . . 4 2 Input drivers of the preamplifier along with the decoupling caps and parasitics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 3 Voltage bias voltage sensing scheme . . . . . . . . . . . . . . . . . . . 8 4 Current bias current... sensing scheme . . . . . . . . . . . . . . . . . . 9 5 Current bias scheme which common mode sense voltage to DE . . . . 10 6 Decoupling the inputs of the differential pair using feedback . . . . . 11 7 Barkhausen noise...

Mellachervu, Ramachandra Murthy

2004-11-15T23:59:59.000Z

150

Missing Thermal Energy of the Intracluster Medium  

E-Print Network [OSTI]

The Sunyaev-Zel'dovich (SZ) effect is a direct probe of thermal energy content of the Universe, induced in the cosmic microwave background (CMB) sky through scattering of CMB photons off hot electrons in the intracluster medium (ICM). We report a 9-sigma detection of the SZ signal in the CMB maps of Wilkinson Microwave Anisotropy Probe (WMAP) 3yr data, through study of a sample of 193 massive galaxy clusters with observed X-ray temperatures greater than 3 keV. For the first time, we make a model-independent measurement of the pressure profile in the outskirts of the ICM, and show that it closely follows the profiles obtained by X-ray observations and numerical simulations. We find that our measurements of the SZ effect would account for only half of the thermal energy of the cluster, if all the cluster baryons were in the hot ICM phase. Our measurements indicate that a significant fraction (35 +/- 8 %) of baryonic mass is missing from the hot ICM, and thus must have cooled to form galaxies, intracluster stars, or an unknown cold phase of the ICM. There does not seem to be enough mass in the form of stars or cold gas in the cluster galaxies or intracluster space, signaling the need for a yet-unknown baryonic component (at 3-sigma level), or otherwise new astrophysical processes in the ICM.

Niayesh Afshordi; Yen-Ting Lin; Daisuke Nagai; Alastair J. R. Sanderson

2006-12-26T23:59:59.000Z

151

Supernovae Driven Turbulence In The Interstellar Medium  

E-Print Network [OSTI]

I model the multi-phase interstellar medium (ISM) randomly heated and shocked by supernovae, with gravity, differential rotation and other parameters we understand to be typical of the solar neighbourhood. The simulations are 3D extending horizontally 1 x 1 kpc squared and vertically 2 kpc, symmetric about the galactic mid-plane. They routinely span gas number densities 1/10000 to 100 per cubic cm, temperatures 100 to 100 MK, speeds up to 10000 km/s and Mach number up to 25. Radiative cooling is applied from two widely adopted parameterizations, and compared directly to assess the sensitivity of the results to cooling. There is strong evidence to describe the ISM as comprising well defined cold, warm and hot regions, which are statistically close to thermal and total pressure equilibrium. This result is not sensitive to the choice of parameters considered here. The distribution of the gas density within each can be robustly modelled as lognormal. Appropriate distinction is required between the properties of t...

Gent, Frederick

2014-01-01T23:59:59.000Z

152

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

E-Print Network [OSTI]

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

Dolphin, Annette C.

153

Capacitively coupled RF voltage probe having optimized flux linkage  

DOE Patents [OSTI]

An RF sensor having a novel current sensing probe and a voltage sensing probe to measure voltage and current. The current sensor is disposed in a transmission line to link all of the flux generated by the flowing current in order to obtain an accurate measurement. The voltage sensor is a flat plate which operates as a capacitive plate to sense voltage on a center conductor of the transmission line, in which the measured voltage is obtained across a resistance leg of a R-C differentiator circuit formed by the characteristic impedance of a connecting transmission line and a capacitance of the plate, which is positioned proximal to the center conductor.

Moore, James A. (Powell, TN); Sparks, Dennis O. (Maryville, TN)

1999-02-02T23:59:59.000Z

154

Enrichment of the Intracluster Medium  

E-Print Network [OSTI]

The relevance of galaxies of different luminosity and mass for the chemical enrichment of the intracluster medium (ICM) is analysed. For this purpose, I adopt the composite luminosity function of cluster galaxies from Trentham (1998), which exhibits a significant rise at the very faint end. The model - adopting a universal Salpeter IMF - is calibrated on reproducing the M_Fe/L_tot, M_Fe/M_*, and alpha/Fe ratios observed in clusters. Although the contribution to total luminosity and ICM metals peaks around L* galaxies (M* approx -20), faint objects with M_B>-18 still provide at least 30 per cent of the metals present in the ICM. In consistency with the solar alpha/Fe ratios determined by {ASCA}, the model predicts that 60 per cent of the ICM iron comes from Type Ia supernovae. The predicted slope of the relation between intracluster gas mass and cluster luminosity emerges shallower than the observed one, indicating that the fraction of primordial gas increases with cluster richness.

D. Thomas

1998-11-25T23:59:59.000Z

155

Method of Controlling Corona Effects and Breakdown Voltage of Small Air Gaps Stressed by Impulse Voltages  

E-Print Network [OSTI]

This paper investigates the influence of a resistor on the dielectric behavior of an air gap. The resistor is connected in series with the air gap and the latter is stressed by impulse voltage. Air gap arrangements of different geometry with either the rod or the plate grounded are stressed with impulse voltages of both positive and negative polarity. The resistor is connected in series with the air gap in the return circuit connecting the gap with the impulse generator. The method followed involves the investigation of the graphs of the charging time concerning the air gaps capacitances, in connection to the value of the resistor, the geometry of the gap, the effect of grounding and the polarity effect. It is determined that the charging time of the air gap increases, as the value of the resistor increases. It is also determined that the peak voltage value of the fully charged air gap decreases as the value of the resistor increases. The results of the mathematical and simulation analysis are compared with the results of the oscillograms taken from experimental work. In addition and consequently to the above results it is concluded from the experimental work that the in series connection of the resistor in the circuit has significant influence on corona pulses (partial discharges) occurring in the gap and on the breakdown voltage of the gap. A new method of controlling the corona effects and consequently the breakdown voltage of small air gaps stressed by impulse voltage of short duration in connection to the ground effect and the polarity effect has arisen. Furthermore through mathematical analysis of the charging graphs obtained from simulation and experimental oscillograms there was a calculation of the values of the capacitance of the air gaps in relation to their geometry and the results were compared to the values calculated with mathematical analysis.

Athanasios Maglaras; Trifon Kousiouris; Frangiskos Topalis; Dimitrios Katsaros; Leandros A. Maglaras; Konstantina Giannakopoulou

2014-10-15T23:59:59.000Z

156

Low voltage ride-through of DFIG and brushless DFIG: Similarities and differences  

Science Journals Connector (OSTI)

Abstract The brushless doubly fed induction generator (BDFIG) has been proposed as a viable alternative in wind turbines to the commonly used doubly fed induction generator (DFIG). The BDFIG retains the benefits of the DFIG, i.e. variable speed operation with a partially rated converter, but without the use of brush gear and slip rings, thereby conferring enhanced reliability. As low voltage ride-through (LVRT) performance of the DFIG-based wind turbine is well understood, this paper aims to analyze LVRT behavior of the BDFIG-based wind turbine in a similar way. In order to achieve this goal, the equivalence between their two-axis model parameters is investigated. The variation of flux linkages, back-EMFs and currents of both types of generator are elaborated during three phase voltage dips. Moreover, the structural differences between the two generators, which lead to different equivalent parameters and hence different LVRT capabilities, are investigated. The analytical results are verified via time-domain simulations for medium size wind turbine generators as well as experimental results of a voltage dip on a prototype 250 kVA BDFIG.

S. Tohidi; P. Tavner; R. McMahon; H. Oraee; M.R. Zolghadri; S. Shao; E. Abdi

2014-01-01T23:59:59.000Z

157

Kirchhoff voltage law corrected for radiating circuits  

E-Print Network [OSTI]

When a circular loop composed by a RLC is put to oscillate, the oscillation will eventually vanish in an exponentially decaying current, even considering superconducting wires, due to the emission of electric and magnetic dipole radiation. In this work we propose a modification on the Kirchhoff voltage law by adding the radiative contributions to the energy loss as an effective resistance, whose value is relatively small when compared to typical resistance value, but fundamental to describe correctly real circuits. We have also analysed the change in the pattern of the radiation spectra emitted by the circuit as we vary both the effective and electrical resistance.

Lara, Vitor

2014-01-01T23:59:59.000Z

158

Jet Fragmentation in Medium and Vacuum with the PHENIX Detector  

E-Print Network [OSTI]

One of the most active areas of investigation in relativistic heavy-ion collisions is the study of the jet quenching phenomenon whereby hard partons lose their energy as they traverse the hot, dense matter created in such collisions. Strong parton energy loss has been observed in central nucleus-nucleus collisions as evidenced by the a large suppression of the yield of high pT hadrons as compared to the expected yield based on measurements in p+p collisions. Moreover, measurements of back-to-back correlations of charged hadrons suggest that jet shapes are strongly modified modified by the medium. The quantitative interpretation of single and di-hadron measurements is, however, complicated by the fact that the initial parton energy is unknown. A more informative measurement would be one in which the initial parton energy is known, allowing the determination of the fragmentation function, which may be effectively modified from its vacuum form by the presence of the medium. Two measurements in which the initial parton energy may be estimated are discussed in these proceedings: jet reconstruction and two- particle correlations using direct photons. Jet reconstruction in nuclear collisions is challenging due to the large background of soft particles, fluctuations of which give rise to fake jets. Direct photons can be used to estimate the initial parton energy of the recoil jet without recourse to jet reconstruction algorithms. However, such studies suffer from a smaller rate and the direct photon signal must be disentangled from a large background of decay photons. We present jet reconstruction results which use an algorithm suitable for a high multiplicity environment. We also present results of two-particle correlations using direct photons. These results are discussed in the context of medium modification to the fragmentation function.

Matthew Nguyen for the PHENIX Collaboration

2010-08-08T23:59:59.000Z

159

Chemical detection and laser wavelength stabilization employing spectroscopic absorption via laser compliance voltage sensing  

DOE Patents [OSTI]

Systems and methods are disclosed that provide a direct indication of the presence and concentration of an analyte within the external cavity of a laser device that employ the compliance voltage across the laser device. The systems can provide stabilization of the laser wavelength. The systems and methods can obviate the need for an external optical detector, an external gas cell, or other sensing region and reduce the complexity and size of the sensing configuration.

Taubman, Matthew S; Phillips, Mark C

2014-03-18T23:59:59.000Z

160

Directives Help  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

All DOE directives are available through this site. While it may seem overwhelming, given the number of documents, we have provided a number of ways in which you may get to the information you need.

Note: This page contains sample records for the topic "direct medium voltage" 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

Safe epoxy encapsulant for high voltage magnetics  

SciTech Connect (OSTI)

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

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

1998-01-01T23:59:59.000Z

162

Accelerator System Development at High Voltage Engineering  

SciTech Connect (OSTI)

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

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

2009-03-10T23:59:59.000Z

163

A renewed look at eta' in medium  

E-Print Network [OSTI]

We revisit the question of whether the U_A(1) symmetry is effectively restored in hot and dense medium. In particular, by generalizing the Witten-Veneziano formula to finite temperature, we investigate whether the mass of eta'-meson will change in medium due to the restoration of chiral symmetry.

Youngshin Kwon; Su Houng Lee; Kenji Morita; Gyuri Wolf

2012-04-14T23:59:59.000Z

164

Chiral Restoration in a Nuclear Medium  

Science Journals Connector (OSTI)

......nuclei and nuclear collisions. At the future Accelerator Facility...Structure of the Vacuum and Elementary...GSI future accelerator facility...antiprotons In a nuclear medium the...function for the vacuum production...mesons in a nuclear medium. With the accelerator facility...Structure of the Vacuum and Elementary......

Paul Kienle

2003-01-01T23:59:59.000Z

165

Rotor current transient analysis of DFIG-based wind turbines during symmetrical voltage faults  

Science Journals Connector (OSTI)

Abstract The impact of grid voltage fault on doubly fed induction generators (DFIGs), especially rotor currents, has received much attention. So, in this paper, the rotor currents of based-DFIG wind turbines are considered in a generalized way, which can be widely used to analyze the cases under different levels of voltage symmetrical faults. A direct method based on space vector is proposed to obtain an accurate expression of rotor currents as a function of time for symmetrical voltage faults in the power system. The presented theoretical analysis is simple and easy to understand and especially highlights the accuracy of the expression. Finally, the comparable simulations evaluate this analysis and show that the expression of the rotor currents is sufficient to calculate the maximum fault current, DC and AC components, and especially helps to understand the causes of the problem and as a result, contributes to adapt reasonable approaches to enhance the fault ride through (FRT) capability of DFIG wind turbines during a voltage fault.

Yu Ling; Xu Cai; Ningbo Wang

2013-01-01T23:59:59.000Z

166

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

Science Journals Connector (OSTI)

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

M. A. Vasyutin

2013-12-01T23:59:59.000Z

167

In-medium NN cross sections determined from stopping and collective flow in intermediate-energy heavy-ion collisions  

E-Print Network [OSTI]

In-medium nucleon-nucleon scattering cross sections are explored by comparing results of quantum molecular dynamics simulations to data on stopping and on elliptic and directed flow in intermediate-energy heavy-ion collisions. The comparison points to in-medium cross sections which are suppressed at low energies but not at higher energies. Positive correlations are found between the degree of stopping and the magnitudes of elliptic and directed flows.

Zhang, Y; Li, Z; Danielewicz, Pawel; Li, Zhuxia; Zhang, Yingxun

2007-01-01T23:59:59.000Z

168

In-medium NN cross sections determined from stopping and collective flow in intermediate-energy heavy-ion collisions  

E-Print Network [OSTI]

In-medium nucleon-nucleon scattering cross sections are explored by comparing results of quantum molecular dynamics simulations to data on stopping and on elliptic and directed flow in intermediate-energy heavy-ion collisions. The comparison points to in-medium cross sections which are suppressed at low energies but not at higher energies. Positive correlations are found between the degree of stopping and the magnitudes of elliptic and directed flows.

Yingxun Zhang; Zhuxia Li; Pawel Danielewicz

2007-03-14T23:59:59.000Z

169

Method to prepare nanoparticles on porous mediums  

DOE Patents [OSTI]

A method to prepare porous medium decorated with nanoparticles involves contacting a suspension of nanoparticles in an ionic liquid with a porous medium such that the particles diffuse into the pores of the medium followed by heating the resulting composition to a temperature equal to or greater than the thermal decomposition temperature of the ionic liquid resulting in the removal of the liquid portion of the suspension. The nanoparticles can be a metal, an alloy, or a metal compound. The resulting compositions can be used as catalysts, sensors, or separators.

Vieth, Gabriel M. (Knoxville, TN) [Knoxville, TN; Dudney, Nancy J. (Oak Ridge, TN) [Oak Ridge, TN; Dai, Sheng (Knoxville, TN) [Knoxville, TN

2010-08-10T23:59:59.000Z

170

High Temperature, High Voltage Fully Integrated Gate Driver Circuit  

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

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

171

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

172

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

E-Print Network [OSTI]

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

Ripunjoy Phukan

2013-10-04T23:59:59.000Z

173

Low voltage ride-through capability improvement of DFIG-based wind turbines under unbalanced voltage dips  

Science Journals Connector (OSTI)

Abstract This paper proposes a competent and effective scheme to enhance the ride-through capability of DFIG-based wind turbines under unbalanced voltage dip conditions. The proposed method is realized through joint use of the rotor-side converter control and a three-phase stator damping resistor (SDR) placed in series with the stator windings. By means of an asymmetrical SDR idea, during the unbalanced voltage dip the SDR resistors are activated only in phase(s) experiencing low voltage. Then, the rotor current is controlled such that no unbalance voltage appears on the stator voltage. The proposed ride-through approach limits the peak values of the rotor inrush current, electromagnetic torque and DFIG transient response at the times of occurrence and clearing the fault. It also suppresses fluctuation of the electromagnetic torque and DFIG transient response appeared during unbalanced voltage dips due to negative sequence component.

Mohsen Rahimi; Mostafa Parniani

2014-01-01T23:59:59.000Z

174

Commercial Reference Building: Medium Office | OpenEI  

Open Energy Info (EERE)

Medium Office Medium Office Dataset Summary Description Commercial reference buildings provide complete descriptions for whole building energy analysis using EnergyPlus simulation software. Included here is data pertaining to the reference building type Medium Office for each of the 16 climate zones, and each of three construction categories: new construction, post-1980 construction existing buildings, pre-1980 construction existing buildings. The dataset includes four key components: building summary, zone summary, location summary and a picture. Building summary includes details about: form, fabric, and HVAC. Zone summary includes details such as: area, volume, lighting, and occupants for all types of zones in the building. Location summary includes key building information as it pertains to each climate zone, including: fabric and HVAC details, utility costs, energy end use, and peak energy demand.In total, DOE developed 16 reference building types that represent approximately 70% of commercial buildings in the U.S.; for each type, building models are available for three categories: new construction, post-1980 construction existing buildings, pre-1980 construction existing buildings. The commercial reference buildings (formerly known as commercial building benchmark models) were developed by the U.S. Department of Energy (DOE), in conjunction with three of its national laboratories.Additional data is available directly from DOE's Energy Efficiency & Renewable Energy (EERE) Website, including EnergyPlus software input files (.idf) and results of the EnergyPlus simulations (.html).

175

Hadrons in the Nuclear Medium  

SciTech Connect (OSTI)

Quantum Chromodynamics, the microscopic theory of strong interactions, has not yet been applied to the calculation of nuclear wave functions. However, it certainly provokes a number of specific questions and suggests the existence of novel phenomena in nuclear physics which are not part of the traditional framework of the meson-nucleon description of nuclei. Many of these phenomena are related to high nuclear densities and the role of color in nucleonic interactions. Quantum fluctuations in the spatial separation between nucleons may lead to local high density configurations of cold nuclear matter in nuclei, up to four times larger than typical nuclear densities. We argue here that experiments utilizing the higher energies available upon completion of the Jefferson Laboratory energy upgrade will be able to probe the quark-gluon structure of such high density configurations and therefore elucidate the fundamental nature of nuclear matter. We review three key experimental programs: quasi-elastic electro-disintegration of light nuclei, deep inelastic scattering from nuclei at x>1, and the measurement of tagged structure functions. These interrelated programs are all aimed at the exploration of the quark structure of high density nuclear configurations. The study of the QCD dynamics of elementary hard processes is another important research direction and nuclei provide a unique avenue to explore these dynamics. We argue that the use of nuclear targets and large values of momentum transfer at would allow us to determine whether the physics of the nucleon form factors is dominated by spatially small configurations of three quarks.

Misak Sargsian; G.A. Miller; John Arrington; William Bertozzi; Werner Boeglin; Carl Carlson; Donal Day; Leonid Frankfurt; Kim Egiyan; Rolf Ent; Shalev Gilad; Keith Griffioen; Douglas Higinbotham; Sebastian Kuhn; Wally Melnitchouk; Eliezer Piasetzky; Stepan Stepanyan; Mark Strikman; Lawrence Weinstein

2002-10-01T23:59:59.000Z

176

A MODEL FOR POROUS-MEDIUM COMBUSTION  

Science Journals Connector (OSTI)

......these applied in coal combustion appears in...understanding of the chemistry of combustion...GLASSMAN, Combustion (Academic Press...ESSENHIGH, In Chemistry of Coal Utilization...POROUS-MEDIUM COMBUSTION 177 8. D. A......

J. NORBURY; A. M. STUART

1989-02-01T23:59:59.000Z

177

Cognitive Medium Access: Exploration, Exploitation and Competition  

E-Print Network [OSTI]

1 Cognitive Medium Access: Exploration, Exploitation and Competition Lifeng Lai, Hesham El Gamal, Hai Jiang and H. Vincent Poor Abstract-- This paper establishes the equivalence between cognitive cognitive user wishes to opportunistically exploit the availability of empty fre- quency bands

El-Gamal, Hesham

178

Definition: Direct current | Open Energy Information  

Open Energy Info (EERE)

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

179

Simplified VO M&V Protocol Simplified Voltage Optimization (VO)  

E-Print Network [OSTI]

Simplified VO M&V Protocol 1 Simplified Voltage Optimization (VO) Measurement and Verification Protocol 1.0 Introduction 1.1 Purpose The Simplified Voltage Optimization (VO) Measurement and Verification requirements, and measurement and verification formulations are included as part of this Protocol. 1

180

Task Scheduling and Voltage Selection for Energy Minimization  

E-Print Network [OSTI]

system con gurations. 1. INTRODUCTION Energy consumption has become a primary concern in today's ICTask Scheduling and Voltage Selection for Energy Minimization Yumin Zhang Synopsys, Inc. 700 East-phase framework that inte- grates task assignment, ordering and voltage selection VS together to minimize energy

Hu, Xiaobo Sharon

Note: This page contains sample records for the topic "direct medium voltage" 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

IMPACT OF DYNAMIC VOLTAGE SCALING (DVS) ON CIRCUIT OPTIMIZATION  

E-Print Network [OSTI]

and dynamic power, respectively. Both gate sizing and Dual-VT are design-time techniques, which are applied to the circuit at a fixed voltage. On the other hand, DVS is a run-time technique and implies that the circuit will be operating at a different voltage...

Esquit Hernandez, Carlos A.

2010-01-16T23:59:59.000Z

182

REFINED RFP LOOP VOLTAGE CALCULATION J.C. Sprott  

E-Print Network [OSTI]

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

Sprott, Julien Clinton

183

LOW VOLTAGE ANALOG CIRCUITS USING STANDARD CMOS TECHNOLOGY  

E-Print Network [OSTI]

LOW VOLTAGE ANALOG CIRCUITS USING STANDARD CMOS TECHNOLOGY Phillip E. Allen, Benjamin J. Blalock, and Gabriel A. Rincon School of Electrical and Computer Engineering Georgia Institute of Technology Atlanta supply voltages in CMOS integrated circuits. As the channel lengths of CMOS technology decrease

Rincon-Mora, Gabriel A.

184

Nonlinear voltages in multiple-lead coherent conductors  

Science Journals Connector (OSTI)

We use the generalized S-matrix approach to study multiple-lead coherent conductors in the case of finite applied voltages. In this framework we discuss the transverse voltage arising in a four-lead conductor with two symmetric biased leads.

Gordey B. Lesovik and Carlo Presilla

1993-01-15T23:59:59.000Z

185

The Cavendish high-voltage laboratory 1935–39  

Science Journals Connector (OSTI)

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

1999-01-01T23:59:59.000Z

186

Spark-safe low-voltage detonator  

DOE Patents [OSTI]

A column of explosive in a low-voltage detonator which makes it spark-safe ncludes an organic secondary explosive charge of HMX in the form of a thin pad disposed in a bore of a housing of the detonator in an ignition region of the explosive column and adjacent to an electrical ignition device at one end of the bore. The pad of secondary charge has an axial thickness within the range of twenty to thirty percent of its diameter. The explosive column also includes a first explosive charge of CP disposed in the housing bore in the ignition region of the explosive column next to the secondary charge pad on a side opposite from the ignition device. The first CP charge is loaded under sufficient pressure, 25 to 40 kpsi, to provide mechanical confinement of the pad of secondary charge and physical coupling thereof with the ignition device. The explosive column further includes a second explosive charge of CP disposed in the housing bore in a transition region of the explosive column next to the first CP charge on a side opposite from the pad of secondary charge. The second CP charge is loaded under sufficient pressure, about 10 kpsi, to allow occurrence of DDT. The first explosive CP charge has an axial thickness within the range of twenty to thirty percent of its diameter, whereas the second explosive CP charge contains a series of increments (nominally 4) each of which has an axial thickness-to-diameter ratio of one to two.

Lieberman, Morton L. (Albuquerque, NM)

1989-01-01T23:59:59.000Z

187

Bonfire-safe low-voltage detonator  

DOE Patents [OSTI]

A column of explosive in a low-voltage detonator which makes it bonfire-safe includes a first layer of an explosive charge of CP, or a primary explosive, and a second layer of a secondary organic explosive charge, such as PETN, which has a degradation temperature lower than the autoignition temperature of the CP or primary explosives. The first layer is composed of a pair of increments disposed in a bore of a housing of the detonator in an ignition region of the explosive column and adjacent to and in contact with an electrical ignition device at one end of the bore. The second layer is composed of a plurality of increments disposed in the housing bore in a transition region of the explosive column next to and in contact with the first layer on a side opposite from the ignition device. The first layer is loaded under a sufficient high pressure, 25 to 40 kpsi, to achieve ignition, whereas the second layer is loaded under a sufficient low pressure, about 10 kpsi, to allow occurrence of DDT. Each increment of the first and second layers has an axial length-to-diameter ratio of one-half.

Lieberman, Morton L. (Albuquerque, NM)

1990-01-01T23:59:59.000Z

188

Definition: Automated Voltage And Var Control | Open Energy Information  

Open Energy Info (EERE)

Voltage And Var Control Voltage And Var Control Jump to: navigation, search Dictionary.png Automated Voltage And Var Control Automated voltage and VAR control requires coordinated operation of reactive power resources such as capacitor banks, voltage regulators, transformer load-tap changers, and distributed generation (DG) with sensors, controls, and communications systems. These devices could operate autonomously in response to local events or in response to signals from a central control system.[1] View on Wikipedia Wikipedia Definition Also Known As Volt-VAR Control (VVC) Related Terms smart grid, Reactive Power References ↑ SmartGrid.gov 'Description of Functions' An i LikeLike UnlikeLike You like this.Sign Up to see what your friends like. nline Glossary Definition Retrieved from

189

Living and Working Safely Around High-Voltage Power Lines.  

SciTech Connect (OSTI)

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

United States. Bonneville Power Administration.

2001-06-01T23:59:59.000Z

190

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

191

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

192

Variable Voltage Substation Electric Fire and Emergency Response  

Broader source: Energy.gov [DOE]

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

193

ON THE PROPAGATION OF ENERGY IN A STRATIFIED GASEOUS MEDIUM  

Science Journals Connector (OSTI)

...MEDIUM Steven Rosencrans MASSACHUSETTS INSTITUTE OF TECHNOLOGY ON...STRATIFIED GASEOUS MEDIUM. | MASSACHUSETTS INSTITUTE OF TECHNOLOGY...MEDIUM* BY STEVEN ROSENCRANS MASSACHUSETTS INSTITUTE OF TECHNOLOGY Communicated...responsible for the heating of the solar corona.6 (The top of our...

Steven Rosencrans

1965-01-01T23:59:59.000Z

194

Direct costing  

E-Print Network [OSTI]

oau 5e reduced. Under the same oonOitions, even ~Me on a bread scale entails not mere1y the conduct of the direct oyeraticns cf yrccessing the materials into finished products, but also the performance of auxiliary functions. these may 'ba power y... purposes have been advanced as folkway le Most of a o03RyaxO' 8 products Grc usual13r sold at prices which oovex' full product costs y plus 861ling a%el administrative expenses, plus normal profit. The inventoi~ valuate. on should be consistent...

Browning, Donald Bullock

2012-06-07T23:59:59.000Z

195

LNT + SCR Aftertreatment for Medium-Heavy Duty Applications:...  

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

+ SCR Aftertreatment for Medium-Heavy Duty Applications: A Systems Approach LNT + SCR Aftertreatment for Medium-Heavy Duty Applications: A Systems Approach Poster presentation at...

196

Small- and Medium-Size Building Automation and Control System...  

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

Small- and Medium-Size Building Automation and Control System Needs: Scoping Study Small- and Medium-Size Building Automation and Control System Needs: Scoping Study Emerging...

197

Removal of Carbon Tetrachloride from a Layered Porous Medium...  

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

Carbon Tetrachloride from a Layered Porous Medium by Means of Soil Vapor Extraction Enhanced by Desiccation and Water Removal of Carbon Tetrachloride from a Layered Porous Medium...

198

Removal of carbon tetrachloride from a layered porous medium...  

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

carbon tetrachloride from a layered porous medium by means of soil vapor extraction enhanced by desiccation and water Removal of carbon tetrachloride from a layered porous medium...

199

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

200

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

Note: This page contains sample records for the topic "direct medium voltage" 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

Improving waveform quality in direct power control of DFIG using fuzzy controller  

Science Journals Connector (OSTI)

This paper proposes a new direct power control (DPC) strategy of double-fed induction generator using fuzzy logic controller. The active and reactive power equations are expanded, and effects of voltage vecto...

H. Z. Boroujeni; M. F. Othman; A. H. Shirdel…

2014-11-01T23:59:59.000Z

202

Category:MediumOffice | Open Energy Information  

Open Energy Info (EERE)

MediumOffice MediumOffice Jump to: navigation, search Go Back to PV Economics By Building Type Media in category "MediumOffice" The following 77 files are in this category, out of 77 total. SVMediumOffice Bismarck ND Montana-Dakota Utilities Co (North Dakota).png SVMediumOffice Bismarc... 72 KB SVMediumOffice Cedar City UT Moon Lake Electric Assn Inc (Utah).png SVMediumOffice Cedar C... 62 KB SVMediumOffice International Falls MN Northern States Power Co (Minnesota) Excel Energy.png SVMediumOffice Interna... 83 KB SVMediumOffice LA CA City of Los Angeles California (Utility Company).png SVMediumOffice LA CA C... 87 KB SVMediumOffice Memphis TN City of Memphis Tennessee (Utility Company).png SVMediumOffice Memphis... 65 KB SVMediumOffice Minneapolis MN Northern States Power Co (Minnesota) Excel Energy.png

203

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

E-Print Network [OSTI]

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

Szabados, Barna

204

Direct numerical simulation of electroconvective instability and hysteretic current-voltage response of a permselective membrane  

E-Print Network [OSTI]

We present a systematic, multiscale, fully detailed numerical modeling for dynamics of fluid flow and ion transport covering Ohmic, limiting, and overlimiting current regimes in conductance of ion-selective membrane. By ...

Pham, Van Sang

205

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

SciTech Connect (OSTI)

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

Eisele, F.L.

1989-05-01T23:59:59.000Z

206

Electro-optic voltage sensor with Multiple Beam Splitting  

DOE Patents [OSTI]

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

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

2000-01-01T23:59:59.000Z

207

Electro-optic voltage sensor with beam splitting  

DOE Patents [OSTI]

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

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

2002-01-01T23:59:59.000Z

208

Panel Session: Optimization Techniques in Voltage Collapse Analysis," IEEE PES Summer Meeting, San Diego, July 14, 1998. Applications of Optimization to Voltage Collapse Analysis  

E-Print Network [OSTI]

Panel Session: Optimization Techniques in Voltage Collapse Analysis," IEEE PES Summer Meeting, San Diego, July 14, 1998. Applications of Optimization to Voltage Collapse Analysis Claudio A. Ca|Thispaper describesseveralapplica- tions of optimization for voltage stability analysis VSA of power systems. Voltage stability prob

Cañizares, Claudio A.

209

In-Medium Properties of Hadrons  

E-Print Network [OSTI]

A diverse experimental program for the study of the photoproduction of mesons off nuclei has been carried out - and is still running - at the Mainz MAMI and Bonn ELSA electron accelerators with the TAPS, Crystal Barrel, and Crystal Ball calorimeters. It is motivated as a detailed study of the in-medium properties of hadrons and the meson - nucleus interactions. Typical examples for the in-medium behavior of vector mesons ($\\omega$), scalar mesons ($\\sigma$), and nucleon resonances (P$_{33}$(1232), S$_{11}$(1535), D$_{15}$(1520)) are discussed. Special attention is paid to meson - nucleus final state interactions.

B. Krusche

2006-08-24T23:59:59.000Z

210

Direct power control of grid connected PV systems with three level NPC inverter  

SciTech Connect (OSTI)

This paper presents the control of a three-level Neutral Point Clamped (NPC) voltage source inverter for grid connected photovoltaic (PV) systems. The control method used is the Extended Direct Power Control (EDPC), which is a generic approach for Direct Power Control (DPC) of multilevel inverters based on geometrical considerations. Maximum Power Point Tracking (MPPT) algorithms, that allow maximal power conversion into the grid, have been included. These methods are capable of extracting maximum power from each of the independent PV arrays connected to each DC link voltage level. The first one is a conventional MPPT which outputs DC link voltage references to EDPC. The second one is based on DPC concept. This new MPPT outputs power increment references to EDPC, thus avoiding the use of a DC link voltage regulator. The whole control system has been tested on a three-level NPC voltage source inverter connected to the grid and results confirm the validity of the method. (author)

Alonso-Martinez, Jaime; Eloy-Garcia, Joaquin; Arnaltes, Santiago [Dept. of Electrical Engineering, University Carlos III of Madrid, Avda. Universidad 30, 28911 Leganes, Madrid (Spain)

2010-07-15T23:59:59.000Z

211

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

E-Print Network [OSTI]

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

Fernando, W. Anand Krisantha

2012-06-07T23:59:59.000Z

212

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

213

High-voltage supply for backward-wave tube  

SciTech Connect (OSTI)

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

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

1986-04-01T23:59:59.000Z

214

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

Science Journals Connector (OSTI)

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

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

2011-01-01T23:59:59.000Z

215

Optically Transparent, Electrically Conductive Composite Medium  

Science Journals Connector (OSTI)

...found below and above these two lower shale beds. Although it is possible that reworking...by the three shocked quartz-bearing shales, but there are at least 250 m of Norian...of the transparent composite medium. anisotropic. The transparency along the ver-tical...

S. JIN; T. H. TIEFEL; R. WOLFE; R. C. SHERWOOD; J. J. MOTTINE JR.

1992-01-24T23:59:59.000Z

216

In-Medium Modifications of Hadron Properties  

E-Print Network [OSTI]

The in-medium modifications of hadron properties are briefly discussed. We restrict the discussion to the lattice QCD calculations for the hadron masses, screening masses, decay constants and wave functions. We review the progress made so far and describe how to broaden its horizon.

A. Tawfik

2006-03-22T23:59:59.000Z

217

High-voltage air-core pulse transformers  

SciTech Connect (OSTI)

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

Rohwein, G. J.

1981-01-01T23:59:59.000Z

218

Eliminate Excessive In-Plant Distribution System Voltage Drops...  

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

connections-can account for less than 1% to more than 4% of total plant electrical energy consumption. This two-page tip sheet recommends conducting a voltage drop survey and...

219

Optical crystal based devices for current and voltage measurement  

SciTech Connect (OSTI)

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

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

1995-07-01T23:59:59.000Z

220

Design & Fabrication of a High-Voltage Photovoltaic Cell  

SciTech Connect (OSTI)

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

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

2012-09-05T23:59:59.000Z

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


221

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

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

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

222

Long term voltage stability analysis for small disturbances  

E-Print Network [OSTI]

This dissertation attempts to establish an analytical and comprehensive framework to deal with two critical challenges associated with voltage stability analysis: 1. To study the new competitive environment appropriately and give more incentive...

Men, Kun

2009-05-15T23:59:59.000Z

223

Voltage asymmetry at the buses of a combined substation  

Science Journals Connector (OSTI)

The voltage asymmetry at the buses of a combined (ac/dc) substation is calculated by phase method, using Mathcad ... , power may be supplied to a combined substation along a common line from a limited-...

A. G. Pakulin; V. A. Zagorskii; V. F. Put’ko

2013-07-01T23:59:59.000Z

224

Operation of buck regulator with ultra-low input voltage  

E-Print Network [OSTI]

Based on the LTC3621 and LTC3624, the designed buck regulator proposed in this thesis aims to lower the allowed input voltage and increase efficiency compared to the original part without making significant changes to ...

Harris, Cory Angelo

2014-01-01T23:59:59.000Z

225

Voltage Regulator Chip: Power Supplies on a Chip  

SciTech Connect (OSTI)

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

None

2010-09-01T23:59:59.000Z

226

Reactive Support and Voltage Control Service: Key Issues and Challenges  

E-Print Network [OSTI]

Reactive Support and Voltage Control Service: Key Issues and Challenges George Gross^, Paolo of Illinois at Urbana-Champaign, Urbana, IL 61801, USA, e-mail gross@uiuc.edu ° Dipartimento di Ingegneria

Gross, George

227

Automotive high-voltage electrical system with integrated safeguard  

Science Journals Connector (OSTI)

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

Thomas Flottmann

2007-03-01T23:59:59.000Z

228

Modeling the operating voltage of liquid metal battery cells  

E-Print Network [OSTI]

A one-dimensional, integrative model of the voltage during liquid metal battery operation has been developed to enhance the understanding of performance at the cell level. Two liquid metal batteries were studied: Mg-Sb for ...

Newhouse, Jocelyn Marie

2014-01-01T23:59:59.000Z

229

Voltage Fade, an ABR Deep Dive Project: Status and Outcomes  

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

Budget * Voltage Fade project * 3,900K Barriers * Calendarcycle life of lithium-ion cells being developed for PHEV and EV batteries that meet or exceed DOEUSABC goals Partners...

230

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

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

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

231

High voltage dry-type air-core shunt reactors  

Science Journals Connector (OSTI)

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

Klaus Papp; Michael R. Sharp…

2014-11-01T23:59:59.000Z

232

High-speed low-voltage ultraviolet light source  

Science Journals Connector (OSTI)

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

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

1984-01-01T23:59:59.000Z

233

Advanced Vehicle Testing Activity: Medium- and Heavy-Duty Vehicles  

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

Medium- and Medium- and Heavy-Duty Vehicles to someone by E-mail Share Advanced Vehicle Testing Activity: Medium- and Heavy-Duty Vehicles on Facebook Tweet about Advanced Vehicle Testing Activity: Medium- and Heavy-Duty Vehicles on Twitter Bookmark Advanced Vehicle Testing Activity: Medium- and Heavy-Duty Vehicles on Google Bookmark Advanced Vehicle Testing Activity: Medium- and Heavy-Duty Vehicles on Delicious Rank Advanced Vehicle Testing Activity: Medium- and Heavy-Duty Vehicles on Digg Find More places to share Advanced Vehicle Testing Activity: Medium- and Heavy-Duty Vehicles on AddThis.com... Home Overview Light-Duty Vehicles Medium- and Heavy-Duty Vehicles Transit Vehicles Trucks Idle Reduction Oil Bypass Filter Airport Ground Support Equipment Medium and Heavy Duty Hybrid Electric Vehicles

234

LM111/LM211/LM311 Voltage Comparator  

E-Print Network [OSTI]

LM111/LM211/LM311 Voltage Comparator 1.0 General Description The LM111, LM211 and LM311 are voltage comparators that have input currents nearly a thousand times lower than devices like the LM106 or LM710A. Both the inputs and the outputs of the LM111, LM211 or the LM311 can be isolated from system ground

Lanterman, Aaron

235

Sinusoidal voltage controlled oscillators using operational transconductance amplifiers  

E-Print Network [OSTI]

SINUSOIDAI. VOLTAGE CONTROLLED OSCILLATORS I. SING OPERATIONAL TRANSCONDUCTANCE AMPLIFIERS A Thesis JAVIFB . IOAQUIN HOYI. K I'ASSANO Suhndtted to the Graduate College ol' 'I'exes A8cM University in partial fulfillment of the requirement... for the degree of MASTER OF SCIENCE May 1985 Major Subject: Electrical Engineering SINUSOIDAL VOLTAGE CONTROLLED OSCILLATORS USING OPERATIONAI, TRANSCONDUCTANCE AMPLIFIERS A Thesis by JAVIER JOAQUIN HOYLE PASSANO Approved as to style and content by: o...

Hoyle Passano, Javier Joaquin

1985-01-01T23:59:59.000Z

236

Image-line voltage controlled oscillators and grating antennas  

E-Print Network [OSTI]

IMAGE-LINE VOLTAGE CONTROLLED OSCILLATORS AND GRATING ANTENNAS A Thesis by ALEXANDER MacDONALD KIRK Submitted to the Office of Graduate Studies of Texas ABM University in partial fulfillment of the requirements for the degree of MASTER... OF SCIENCE May 1991 Major Subject: Electrical Engineering IMAGE-LINE VOLTAGE CONTROLLED OSCILLATORS AND GRATING ANTENNAS A Thesis by ALEXANDER MacDONALD KIRK Approved as to style and content by: Kai Chang (Chair of Committee) Robert D. Nevels...

Kirk, Alexander MacDonald

1991-01-01T23:59:59.000Z

237

Design issues for high voltage converters for ion engines  

SciTech Connect (OSTI)

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

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

1995-12-31T23:59:59.000Z

238

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

239

Oil displacement through a porous medium with a temperature gradient  

E-Print Network [OSTI]

We investigate the effect of a temperature gradient on oil recovery in a two-dimensional pore-network model. The oil viscosity depends on temperature as, $\\mu_o=exp(B/T)$, where $B$ is a physico-chemical parameter depending on the type of oil, and $T$ is the temperature. A temperature gradient is applied across the medium in the flow direction. Initially, the porous medium is saturated with oil and, then, another fluid is injected. We have considered two cases representing different injection strategies. In the first case, the invading fluid viscosity is constant (finite viscosity ratio) while in the second one, the invading fluid is inviscid (infinite viscosity ratio). Our results show that, for the case of finite viscosity ratio, recovery increases with $\\Delta T$ independently on strength or sign of the gradient. For an infinite viscosity ratio, a positive temperature gradient is necessary to enhance recovery. Moreover, we show that, for $\\Delta T>0$, the percentage of oil recovery generally decreases (inc...

Oliveira, C L N; Herrmann, H J

2011-01-01T23:59:59.000Z

240

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

E-Print Network [OSTI]

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

Park, Sangtak

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "direct medium voltage" 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

Integrated, Low Voltage, DynamicallyIntegrated, Low Voltage, Dynamically Adaptive BuckAdaptive Buck--Boost ConverterBoost Converter  

E-Print Network [OSTI]

Improvement in battery life Low voltage Single cell operation (Li-ion/NiCd/NiMH/Fuel Cell) Integrated Linearity degradation #12;55Georgia Tech Analog Consortium Biranchinath Sahu School of Electrical

Rincon-Mora, Gabriel A.

242

Axial thermal medium delivery tubes and retention plates for a gas turbine rotor  

DOE Patents [OSTI]

In a multi-stage turbine rotor, tubes are disposed in openings adjacent the rotor rim for flowing a thermal medium to rotor buckets and returning spent thermal medium. The tubes have axially spaced lands of predetermined wall thickness with thin-walled tube sections between the lands and of increasing thickness from the forward to the aft ends of the tubes. A pair of retention plates are carried on the aft end face of the aft wheel and straddle the tube and engage against a shoulder on the tube to preclude displacement of the tube in an aft direction.

Mashey, Thomas Charles (Coxsackie, NY)

2002-01-01T23:59:59.000Z

243

Some properties of convective oscillations in porous medium  

SciTech Connect (OSTI)

Convective oscillations in porous media are studied numerically. A two-dimensional square, differentially heated cavity, filled with a saturated porous medium, is considered subject to linear harmonic oscillations in the vertical direction. The formulation is based on the Darcy-Boussinesq model. The problem includes three nondimensional parameters: the Rayleigh number for porous media Ra, its vibrational analog Ra{sub v}, and the nondimensional frequency f. The time-dependent Darcy-Boussinesq equations have been solved using a pseudo-spectral Chebyshev collocation method. The instantaneous fields of the established oscillatory regimes are presented. Also, some instantaneous and mean characteristics are studied and discussed. The distinctions from the case of viscous fluid alone are emphasized.

Khallouf, H.; Mojitabi, A. [Univ. Paul Sabatier, Toulouse (France); Gershuni, G.Z. [Perm State Univ. (Russian Federation). Dept. of Theoretical Physics

1996-11-08T23:59:59.000Z

244

Medium-fi EvaluationMedium-fi PrototypesMedium-fi DesignLow-fi EvaluationLow-fi Prototypes What is Aphasia?  

E-Print Network [OSTI]

Medium-fi EvaluationMedium-fi PrototypesMedium-fi DesignLow-fi EvaluationLow-fi Prototypes What Cycle Investigated ability of existing technologies to fulfill needs. Extra time is needed to ensure. Evaluated with two participants. One had aphasia as a result of a brain tumour and the other as a result

Findlater, Leah

245

Physical vacuum is a special superfluid medium  

E-Print Network [OSTI]

The Navier-Stokes equation contains two terms which have been subjected to slight modification: (a) the viscosity term depends of time (the viscosity in average on time is zero, but its variance is non-zero); (b) the pressure gradient contains an added term describing the quantum entropy gradient multiplied by the pressure. Owing to these modifications, the Navier-Stokes equation can be reduced to the Schr\\"odinger equation describing behavior of a particle into the vacuum being as a superfluid medium. Vortex structures arising in this medium show infinitely long life owing to zeroth average viscosity. The non-zero variance describes exchange of the vortex energy with zero-point energy of the vacuum. Radius of the vortex trembles around some average value. This observation sheds the light to the Zitterbewegung phenomenon. The long-lived vortex has a non-zero core where the vortex velocity vanishes.

Sbitnev, Valeriy I

2015-01-01T23:59:59.000Z

246

Transient multiwave mixing in a nonlinear medium  

Science Journals Connector (OSTI)

We present a detailed quantitative theory of transient multiwave mixing effects in a nonlinear medium produced by two incident coherent laser beams. Our theory accounts for all the relevant parameters such as laser pulse widths, medium response times, nonlinearities, interaction length, intensities, beam ratio, phase-modulation effects, losses, side diffractions, and explicitly shows how the dynamics and the multiwave mixing processes are interrelated with these parameters. The crucial role played by the diffracted beams and the time-dependent phase shifts among the beams and the interplay among the various intensity and index gratings are explicitly evaluated. In particular, the gain experienced by a weak incident probe beam via these mixing effects from the incident strong pump beam is investigated as a function of the aforementioned parameters.

I. C. Khoo and Ping Zhou

1990-02-01T23:59:59.000Z

247

JC3 Medium Impact Assessment Bulletins  

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

medium-impact-assessment-bulletins medium-impact-assessment-bulletins Office of the Chief Information Officer 1000 Independence Ave., SW Washington, DC 202-586-0166 en V-237: TYPO3 Security Bypass Vulnerabilities http://energy.gov/cio/articles/v-237-typo3-security-bypass-vulnerabilities V-237: TYPO3 Security Bypass Vulnerabilities

248

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

249

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

250

Alternative Fuels Data Center: Medium-Duty Vehicle Idle Reduction  

Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

Medium-Duty Vehicle Medium-Duty Vehicle Idle Reduction Strategies to someone by E-mail Share Alternative Fuels Data Center: Medium-Duty Vehicle Idle Reduction Strategies on Facebook Tweet about Alternative Fuels Data Center: Medium-Duty Vehicle Idle Reduction Strategies on Twitter Bookmark Alternative Fuels Data Center: Medium-Duty Vehicle Idle Reduction Strategies on Google Bookmark Alternative Fuels Data Center: Medium-Duty Vehicle Idle Reduction Strategies on Delicious Rank Alternative Fuels Data Center: Medium-Duty Vehicle Idle Reduction Strategies on Digg Find More places to share Alternative Fuels Data Center: Medium-Duty Vehicle Idle Reduction Strategies on AddThis.com... More in this section... Idle Reduction Benefits & Considerations Heavy-Duty Vehicles Medium-Duty Vehicles

251

Screening masses in thermal and dense medium  

E-Print Network [OSTI]

Screening masses of different hadronic states are studied in thermal and dense medium on lattice. It has been found that screening masses increase with the temperature. In deconfinement phase, chemical potential enhances the screening masses. We use the normalization with respect to lowest Matsubara frequency to characterize dissolving of hadronic bound states at high temperatures. It has been found that different hadronic states have different dissolving temperatures and their survivals are considerably improved at finite chemical potentials.

A. Tawfik

2006-05-29T23:59:59.000Z

252

Exploring medium effects on the nuclear force  

SciTech Connect (OSTI)

This STI product contains a description of results from theoretical studies in nuclear physics. The goal is a systematic investigation of the nuclear force in the nuclear medium. The problems addressed are: density-dependent effective interactions as seen through proton-nucleus reactions, nuclear matter with unequal densities of protons and neutrons, applications to asymmetric nuclei through predictions of neutron radii and neutron skins.

F. Sammarruca

2004-04-18T23:59:59.000Z

253

MHK Technologies/Oregon State University Columbia Power Technologies Direct  

Open Energy Info (EERE)

State University Columbia Power Technologies Direct State University Columbia Power Technologies Direct Drive Point Absorber < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Oregon State University Columbia Power Technologies Direct Drive Point Absorber.jpg Technology Profile Primary Organization Oregon State University OSU Project(s) where this technology is utilized *MHK Projects/OSU Direct Drive Power Generation Buoys Technology Resource Click here Wave Technology Type Click here Point Absorber Technology Readiness Level Click here TRL 1-3: Discovery / Concept Definition / Early Stage Development & Design & Engineering Technology Description When the coil experiences a changing magnetic field created by the heaving magnets voltage is generated Technology Dimensions

254

In-medium NN cross sections determined from the nuclear stopping and collective flow in heavy-ion collisions at intermediate energies  

SciTech Connect (OSTI)

In-medium nucleon-nucleon scattering cross sections are explored by comparing results of quantum molecular dynamics simulations to data on stopping and on elliptic and directed flow in intermediate-energy heavy-ion collisions. The comparison points to in-medium cross sections which are suppressed at low energies but not at higher energies. Positive correlations are found between the degree of stopping and the magnitudes of elliptic and directed flows.

Zhang Yingxun [China Institute of Atomic Energy, P.O. Box 275 (18), Beijing 102413 (China); Li Zhuxia [China Institute of Atomic Energy, P.O. Box 275 (18), Beijing 102413 (China); Center of Theoretical Nuclear Physics, National Laboratory of Lanzhou Heavy Ion Accelerator, Lanzhou 730000 (China); Institute of Theoretical Physics, Chinese Academic of Science, Beijing 100080 (China); Danielewicz, Pawel [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States)

2007-03-15T23:59:59.000Z

255

Minimization of voltage deviation and power losses in power networks using Pareto optimization methods  

Science Journals Connector (OSTI)

Voltage regulation is an important task in electrical engineering for controlling node voltages in a power network. A widely used solution for the problem of voltage regulation is based on adjusting the taps in under load tap changers (ULTCs) power transformers ... Keywords: Multi-objective optimization, Power distribution network, Power losses, Under load tap changers, Voltage regulation

Francisco G. Montoya; Raúl Bańos; Consolación Gil; Antonio Espín; Alfredo Alcayde; Julio Gómez

2010-08-01T23:59:59.000Z

256

Requirements for a Standard Test to Rate the Durability of PV Modules at System Voltage (Presentation)  

SciTech Connect (OSTI)

Degradation modes in photovoltaic modules under system bias voltage stress are described and classified.

Hacke, P.; Terwilliger, K.; Glick, S.; Kempe, M.; Kurtz, S.; Bennett, I.; Kloos, M.

2011-02-01T23:59:59.000Z

257

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

Science Journals Connector (OSTI)

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

1963-08-31T23:59:59.000Z

258

Elevated voltage level I.sub.DDQ failure testing of integrated circuits  

DOE Patents [OSTI]

Burn in testing of static CMOS IC's is eliminated by I.sub.DDQ testing at elevated voltage levels. These voltage levels are at least 25% higher than the normal operating voltage for the IC but are below voltage levels that would cause damage to the chip.

Righter, Alan W. (Albuquerque, NM)

1996-01-01T23:59:59.000Z

259

Elevated voltage level I{sub DDQ} failure testing of integrated circuits  

DOE Patents [OSTI]

Burn in testing of static CMOS IC`s is eliminated by I{sub DDQ} testing at elevated voltage levels. These voltage levels are at least 25% higher than the normal operating voltage for the IC but are below voltage levels that would cause damage to the chip. 4 figs.

Righter, A.W.

1996-05-21T23:59:59.000Z

260

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

SciTech Connect (OSTI)

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

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

2012-03-15T23:59:59.000Z

Note: This page contains sample records for the topic "direct medium voltage" 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

Voltage controlled stand-alone microhydro induction generator system  

Science Journals Connector (OSTI)

The paper discusses simulated control cases of the wound rotor self-excited induction generator WRSEIG. The generator external controller is designed to regulate the output voltage and frequency for constant or variable speed operation of the prime mover and has the inherent capability of protecting the load from short circuit, which permits voltage collapse under heavy loads. WRSEIG is self-excited using one set of excitation capacitance connected across the generator stator side. At the rotor side, a PWM controlled resistor is connected to the rotor windings through the rotating slips and act as a slip power controller. The controller can be configured to regulate the voltage as the speed or the load changes. The presented system has the capability to generate good quality AC power source with minimum controlling elements and can operate under constant or adjustable prime mover speed that suits many microhydro electricity-generating plants.

K.A. Nigim

2005-01-01T23:59:59.000Z

262

Voltage Impacts of Utility-Scale Distributed Wind  

SciTech Connect (OSTI)

Although most utility-scale wind turbines in the United States are added at the transmission level in large wind power plants, distributed wind power offers an alternative that could increase the overall wind power penetration without the need for additional transmission. This report examines the distribution feeder-level voltage issues that can arise when adding utility-scale wind turbines to the distribution system. Four of the Pacific Northwest National Laboratory taxonomy feeders were examined in detail to study the voltage issues associated with adding wind turbines at different distances from the sub-station. General rules relating feeder resistance up to the point of turbine interconnection to the expected maximum voltage change levels were developed. Additional analysis examined line and transformer overvoltage conditions.

Allen, A.

2014-09-01T23:59:59.000Z

263

Operability and Emissions from a Medium-Duty Fleet Operating...  

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

Operability and Emissions from a Medium-Duty Fleet Operating with GTL Fuel and Catalyzed DPFs Operability and Emissions from a Medium-Duty Fleet Operating with GTL Fuel and...

264

Self-Excited ac High Voltage Generation Using Water Droplets  

Science Journals Connector (OSTI)

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

Markus Zahn

1973-01-01T23:59:59.000Z

265

Voltage Control Devices on the IEEE 8500 Node Test Feeder  

SciTech Connect (OSTI)

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

266

Reduction of interference on substation low voltage wiring  

SciTech Connect (OSTI)

This paper describes test results and mitigation methods of electromagnetic interference (EMI) on control and low voltage circuits in substations caused by air disconnect switch operation. The tests are focused on a comparison between unshielded and shielded circuits from capacitively coupled voltage transformers (CCVT) and other equipment circuits in the vicinity. New test data are presented comparing unshielded and shielded cables and transient currents on all connections to the CCVT including the pedestal and ground strap. The paper gives a practical and understandable explanation of the causes of EMI in substations and how shielded cable and parallel ground conductors reduce interference. Design guidelines are listed in the Conclusion.

Gavazza, R.J. [Pacific Gas and Electric Co., San Francisco, CA (United States)] [Pacific Gas and Electric Co., San Francisco, CA (United States); Wiggins, C.M. [Carl M. Wiggins and Associates, Friendswood, TX (United States)] [Carl M. Wiggins and Associates, Friendswood, TX (United States)

1996-07-01T23:59:59.000Z

267

Conditions for Capacitor Voltage Regulation in a Five-Level Cascade Multilevel Inverter: Application to Voltage-Boost in a PM Drive  

E-Print Network [OSTI]

Conditions for Capacitor Voltage Regulation in a Five-Level Cascade Multilevel Inverter Abstract-- A cascade multilevel inverter is a power electronic device built to synthesize a desired AC voltage from several levels of DC voltages. Such inverters have been the subject of research in the last

Tolbert, Leon M.

268

Bi-directional Current-fed Medium Frequency Transformer Isolated AC-DC Converter  

E-Print Network [OSTI]

and the development of new grid systems like HVDC transmission lines. The new solution proposed needs to incorporate methods for the renewable sources to receive power for monitoring and control, during periods of zero production. This calls for a power converter...

Essakiappan, Somasundaram

2011-08-08T23:59:59.000Z

269

Comparative study of voltage oriented and frequency coordinated control of grid connected doubly fed induction generator  

Science Journals Connector (OSTI)

In this paper a comparative study between voltage oriented control (VOC) and frequency coordinated control (FCC) of grid connected doubly fed induction generator (DFIG) is presented. The two method controls are deeply done on DFIG converter sides grid side converter (GSC) and rotor side converter (RSC). The VOC method permanently maintains the DFIG reactive power to zero values to achieve stable voltage. This control is implemented by regulating the rotor direct axis reference current in RSC using grid reactive power. On the other hand the FCC has employed the active power obtaining from the system frequency deviation to control the rotor quadrature axis reference current in the RSC. The GSC is the same in two studies and its applied vector controlled method. The comparison study between the two methods is conducted at a steady and dynamic state under constant and variable wind speeds. The simulation results are carried out by using PSCAD/EMTDC electromagnetic transient program to validate the comparison study between two methods control of DFIG. The outcomes of the simulation show that the VOC is very convenient when the DFIG operated at transient mode and variable wind speeds while the FCC is feasible and effective for steady-state mode applications. Furthermore the FCC method has an ability to reduce the active and reactive powers ripples as well as decreasing torque harmonics. Both of two methods had fewer transient recovery values of output parameters which ensure safety dynamic response of DFIG and power system. This study contributes significantly to choose the suitable control of the DFIG converters according to electrical grid operation conditions. In addition if a joint control has been applied to these two methods the wind power gained strong and flexible control of the frequency and voltage for different operating conditions.

Li Yang

2014-01-01T23:59:59.000Z

270

Hybrid high direct current circuit interrupter  

DOE Patents [OSTI]

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

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

1998-08-11T23:59:59.000Z

271

Hybrid high direct current circuit interrupter  

DOE Patents [OSTI]

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

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

1998-01-01T23:59:59.000Z

272

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

SciTech Connect (OSTI)

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

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

2009-05-01T23:59:59.000Z

273

Power Grid Voltage Integrity Verification Department of ECE  

E-Print Network [OSTI]

Power Grid Voltage Integrity Verification Maha Nizam Department of ECE University of Toronto devgan@magma-da.com ABSTRACT Full-chip verification requires one to check if the power grid is safe, i of the circuit attached to the grid, thereby precluding early verification of the grid. We propose a power grid

Najm, Farid N.

274

Voltage Regulation through Smart Utilization of Potential Reactive Power Resources  

Science Journals Connector (OSTI)

The introduction of demand response concept, in addition to increment of penetration of distributed generation (DG) based on renewable energies, make opportunities for the novel control schemes to be integrated in power system on a smart grid framework. ... Keywords: Demand response, distributed generation, reactive power, renewable energy, smart grid, voltage control

H. Kazari; A. Abbaspour-Tehrani Fard; A. S. Dobakhshari; A. M. Ranjbar

2011-11-01T23:59:59.000Z

275

ORIGINAL ARTICLES Induced Transmembrane Voltage and Its Correlation  

E-Print Network [OSTI]

to investigate the correlation between DWm and molecular transport through an elec- troporated membrane to a voltage (electric potential difference) caused by a system of ion pumps and channels in the membrane, or electropermea- bilization, and permits transmembrane transport of mole- cules for which an intact membrane

Ljubljana, University of

276

Topical Review Voltage Dependence of the Na/K Pump  

E-Print Network [OSTI]

or ``ion well'' hy- pothesis. There are only two ways that net transport can be voltage dependent. Either of the external Na+ and K+ bind- ing sites within the membrane field. This access channel or ``ion well produced by applying a blocking Key words: Na,K-ATPase -- Membrane potential -- Access channel -- Ion well

Gadsby, David

277

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

278

Load Balancing in Wireless Sensor Networks using Kirchhoff's Voltage Law  

E-Print Network [OSTI]

Load Balancing in Wireless Sensor Networks using Kirchhoff's Voltage Law Stavros Toumpis Electrical balancing in wireless networks with a single class of traffic, focusing our attention on an important example, i.e., Wireless Sensor Networks. The analysis is based on the Wireless Minimum Cost Problem

Toumpis, Stavros

279

Power and Voltage Smooth Control of Doubly Fed Induction Generator  

Science Journals Connector (OSTI)

Doubly-fed induction generator (DFIG) is the leading in wind power technology currently. In this paper, decoupling control of DFIG is studied and a new energy storage device is used in the smooth control of DFIG system's power and voltage. This new method ... Keywords: Doubly fed induction generator, Energy storage device, Decoupling control

An-Ren Ma; Cai-Xia Wang; Zhi-Wen Zhou; Tao Wu

2012-07-01T23:59:59.000Z

280

Analysis on DFIG Wind Power System Low-Voltage Ridethrough  

Science Journals Connector (OSTI)

Due to the double fed induction generator’s (DFIG) advantage of controlling active and reactive power independently and partial power converter, DFIG is becoming a popular type of wind power generation system. Nowadays, the grid code demands that ... Keywords: VSCF, DFIG, LVRT, Crowbar, Voltage sags

Yulong Wang; Jianlin Li; Shuju Hu; Honghua Xu

2009-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "direct medium voltage" 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

SVC Voltage Regulator Based on Fractional Order PID  

Science Journals Connector (OSTI)

Contradiction exist between rapid and smooth in the dynamic adjustment process of SVC, however, Fractional order PID controller has two degrees of freedom more than the integer order PID controller, and it has better control performance. This article ... Keywords: SVC, Fractional order PID, Voltage regulator, Oustaloup

Manyu Liu; Huaying Dong; Guishu Liang

2012-12-01T23:59:59.000Z

282

Way to reduce arc voltage losses in hybrid thermionic converters  

SciTech Connect (OSTI)

Experimental results are reported concerning the output and emission characteristics of the arc and hybrid regimes in a plane-parallel thermionic converter with Pt--Zr--O electrode pair. It is shown that arc voltage losses can be reduced to values below those obtainable in ordinary arc thermionic converters.

Tskhakaya, V.K.; Yarygin, V.I.

1982-03-01T23:59:59.000Z

283

Field Optimization of Three Dimensional High Voltage C. Trinitis  

E-Print Network [OSTI]

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

Stamatakis, Alexandros

284

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

285

High Voltage DC Transmission 2 1.0 Introduction  

E-Print Network [OSTI]

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

McCalley, James D.

286

Alternative Fuels Data Center: Medium-Speed and Neighborhood Electric  

Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

Medium-Speed and Medium-Speed and Neighborhood Electric Vehicle (NEV) Definition and Access to Roadways to someone by E-mail Share Alternative Fuels Data Center: Medium-Speed and Neighborhood Electric Vehicle (NEV) Definition and Access to Roadways on Facebook Tweet about Alternative Fuels Data Center: Medium-Speed and Neighborhood Electric Vehicle (NEV) Definition and Access to Roadways on Twitter Bookmark Alternative Fuels Data Center: Medium-Speed and Neighborhood Electric Vehicle (NEV) Definition and Access to Roadways on Google Bookmark Alternative Fuels Data Center: Medium-Speed and Neighborhood Electric Vehicle (NEV) Definition and Access to Roadways on Delicious Rank Alternative Fuels Data Center: Medium-Speed and Neighborhood Electric Vehicle (NEV) Definition and Access to Roadways on Digg

287

Building Technologies Office: Small- and Medium-Sized Building Automation  

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

Small- and Medium-Sized Small- and Medium-Sized Building Automation and Control System Needs: Scoping Study Research Project to someone by E-mail Share Building Technologies Office: Small- and Medium-Sized Building Automation and Control System Needs: Scoping Study Research Project on Facebook Tweet about Building Technologies Office: Small- and Medium-Sized Building Automation and Control System Needs: Scoping Study Research Project on Twitter Bookmark Building Technologies Office: Small- and Medium-Sized Building Automation and Control System Needs: Scoping Study Research Project on Google Bookmark Building Technologies Office: Small- and Medium-Sized Building Automation and Control System Needs: Scoping Study Research Project on Delicious Rank Building Technologies Office: Small- and Medium-Sized Building

288

On the Virial Theorem for Interstellar Medium  

SciTech Connect (OSTI)

An attempt has been made to derive a version of the virial integral that would describe average properties of the interstellar medium (ISM). It is suggested to eliminate the (large) contribution of stellar matter by introducing 'exclusion zones' surrounding stars. Such an approach leads to the appearance of several types of additional surface integrals in the general expression. Their contribution depends on the rate of energy and matter exchange between the stars and ISM. If this exchange is weak, one can obtain a desired virial integral for ISM. However, the presence of intermittent large-scale energetic events significantly constrains the applicability of the virial theorem. If valid, the derived virial integral is dominated by cold molecular/atomic clouds, with only minor contribution of the global magnetic field and low-density warm part.

Ryutov, D

2007-09-24T23:59:59.000Z

289

Light Vector Mesons in the Nuclear Medium  

SciTech Connect (OSTI)

The light vector mesons ($\\rho$, $\\omega$, and $\\phi$) were produced in deuterium, carbon, titanium, and iron targets in a search for possible in-medium modifications to the properties of the $\\rho$ meson at normal nuclear densities and zero temperature. The vector mesons were detected with the CEBAF Large Acceptance Spectrometer (CLAS) via their decays to $e^{+}e^{-}$. The rare leptonic decay was chosen to reduce final-state interactions. A combinatorial background was subtracted from the invariant mass spectra using a well-established event-mixing technique. The $\\rho$ meson mass spectrum was extracted after the $\\omega$ and $\\phi$ signals were removed in a nearly model-independent way. Comparisons were made between the $\\rho$ mass spectra from the heavy targets ($A > 2$) with the mass spectrum extracted from the deuterium target. With respect to the $\\rho$-meson mass, we obtain a small shift compatible with zero. Also, we measure widths consistent with standard nuclear many-body eff

Wood, Michael; Nasseripour, Rakhsha; Weygand, Dennis; Djalali, Chaden; Tur, Clarisse; Mosel, Ulrich; Muehlich, Pascal; Adams, Gary; Amaryan, Moscov; Amaryan, Moskov; Ambrozewicz, Pawel; Anghinolfi, Marco; Asryan, Gegham; Avagyan, Harutyun; Baghdasaryan, Hovhannes; Baillie, Nathan; Ball, James; Baltzell, Nathan; Barrow, Steve; Battaglieri, Marco; Bedlinskiy, Ivan; Bektasoglu, Mehmet; Bellis, Matthew; Benmouna, Nawal; Berman, Barry; Biselli, Angela; Blaszczyk, Lukasz; Bouchigny, Sylvain; Boyarinov, Sergey; Bradford, Robert; Branford, Derek; Briscoe, William; Brooks, William; Burkert, Volker; Butuceanu, Cornel; Calarco, John; Careccia, Sharon; Carman, Daniel; Carnahan, Bryan; Casey, Liam; Chen, Shifeng; Cheng, Lu; Cole, Philip; Collins, Patrick; Coltharp, Philip; Crabb, Donald; Crannell, Hall; Crede, Volker; Cummings, John; Dashyan, Natalya; De Vita, Raffaella; De Sanctis, Enzo; Degtiarenko, Pavel; Denizli, Haluk; Dennis, Lawrence; Deur, Alexandre; Dharmawardane, Kahanawita; Dickson, Richard; Dodge, Gail; Doughty, David; Dugger, Michael; Dytman, Steven; Dzyubak, Oleksandr; Egiyan, Hovanes; Egiyan, Kim; Elfassi, Lamiaa; Elouadrhiri, Latifa; Eugenio, Paul; Fedotov, Gleb; Feldman, Gerald; Feuerbach, Robert; Fradi, Ahmed; Funsten, Herbert; Garcon, Michel; Gavalian, Gagik; Gilfoyle, Gerard; Giovanetti, Kevin; Girod, Francois-Xavier; Goetz, John; Gordon, Christopher; Gothe, Ralf; Griffioen, Keith; Guidal, Michel; Guler, Nevzat; Guo, Lei; Gyurjyan, Vardan; Hadjidakis, Cynthia; Hafidi, Kawtar; Hakobyan, Hayk; Hakobyan, Rafael; Hanretty, Charles; Hardie, John; Hassall, Neil; Hersman, F.; Hicks, Kenneth; Hleiqawi, Ishaq; Holtrop, Maurik; Hyde, Charles; Ilieva, Yordanka; Ireland, David; Ishkhanov, Boris; Isupov, Evgeny; Ito, Mark; Jenkins, David; Jo, Hyon-Suk; Johnstone, John; Joo, Kyungseon; Juengst, Henry; Kalantarians, Narbe; Kellie, James; Khandaker, Mahbubul; Khetarpal, Puneet; Kim, Wooyoung; Klein, Andreas; Klein, Franz; Klimenko, Alexei; Kossov, Mikhail; Krahn, Zebulun; Kramer, Laird; Kubarovsky, Valery; Kuhn, Joachim; Kuhn, Sebastian; Kuleshov, Sergey; Lachniet, Jeff; Laget, Jean; Langheinrich, Jorn; Lawrence, David; Li, Ji; Livingston, Kenneth; Lu, Haiyun; MacCormick, Marion; Markov, Nikolai; Mattione, Paul; McAleer, Simeon; McKinnon, Bryan; McNabb, John; Mecking, Bernhard; Mehrabyan, Surik; Melone, Joseph; Mestayer, Mac; Meyer, Curtis; Mibe, Tsutomu; Mikhaylov, Konstantin; Minehart, Ralph; Mirazita, Marco; Miskimen, Rory; Mokeev, Viktor; Moriya, Kei; Morrow, Steven; Moteabbed, Maryam; Mueller, James; Munevar Espitia, Edwin; Mutchler, Gordon; Nadel-Turonski, Pawel; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria-Ioana; Niczyporuk, Bogdan; Niroula, Megh; Niyazov, Rustam; Nozar, Mina; Osipenko, Mikhail; Ostrovidov, Alexander; Park, Kijun; Pasyuk, Evgueni; Paterson, Craig; Pereira, Sergio; Pierce, Joshua; Pivnyuk, Nikolay; Pocanic, Dinko; Pogorelko, Oleg; Pozdnyakov, Sergey; Preedom, Barry; Price, John; Prok, Yelena; Protopopescu, Dan; Raue, Brian; Riccardi, Gregory; Ricco, Giovanni; Ripani, Marco; Ritchie, Barry; Ronchetti, Federico; Rosner, Guenther; Rossi, Patrizia; Sabatie, Franck; Salamanca, Julian; Salgado, Carlos; Santoro, Joseph; Sapunenko, Vladimir; Schumacher, Reinhard; Serov, Vladimir; Sharabian, Youri; Sharov, Dmitri; Shvedunov, Nikolay; Smith, Elton; Smith, Lee; Sober, Daniel; Sokhan, Daria; Stavinsky, Aleksey; Stepanyan, Stepan; Stepanyan, Samuel; Stokes, Burnham; Stoler, Paul; Strakovski, Igor; Strauch, Steffen; Taiuti, Mauro; Tedeschi, David; Tkabladze, Avtandil; Tkachenko, Svyatoslav; Todor, Luminita; Ungaro, Maurizio; Vineyard, Michael; Vlassov, Alexander; Watts, Daniel; Weinstein, Lawrence; Williams, Michael; Wolin, Elliott; Yegneswaran, Amrit; Zana, Lorenzo; Zhang, Bin; Zhang, Jixie; Zhao, Bo; Zhao, Zhiwen

2008-07-01T23:59:59.000Z

290

Orthopositronium-orthopositronium scattering at medium energies  

SciTech Connect (OSTI)

The scattering of ortho-positronium (o-Ps) atoms has been investigated using the first Born approximation (FBA) and Born-Oppenheimer (B-O) model at medium energies. The angle integrated total elastic cross sections of o-Ps-o-Ps scattering have been reported. Apart from this, the inelastic cross sections for discrete excitations (principal quantum number, n{<=}3) of the single and both the Ps atoms as well as single and double Ps atom ionization have also been obtained. We have also predicted the total cross section of o-Ps-o-Ps scattering by adding all these partial cross sections. The first Born and B-O scattering amplitudes have also been evaluated using partial wave technique. It has been noticed that odd values of the partial wave B-O amplitude vanishes for even parity transitions and vice versa. To the best of our knowledge, this feature has not been noticed for other systems.

Chakraborty, Sumana; Ghosh, A.S. [Department of Theoretical Physics, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700 032 (India); Kumari, Kiran [Department of Physics, R N College, Hajipur (Vaishali), B R A Bihar University, Muzaffarpur, Bihar (India)

2005-08-15T23:59:59.000Z

291

Optimizing Medium Baseline Reactor Neutrino Experiments  

E-Print Network [OSTI]

10 years from now medium baseline reactor neutrino experiments will attempt to determine the neutrino mass hierarchy from the observed antineutrino spectra. In this letter we present the results of more than four million detailed simulations of such experiments, studying the dependence of the probability of successfully determining the hierarchy upon the analysis method, the neutrino mass matrix parameters, reactor flux models and, in particular, combinations of baselines. We show that the strong dependence of the hierarchy determination upon mass differences and flux models found by Qian et al. results from a spurious dependence of the Fourier analysis upon the high energy tail of the reactor spectrum which can be removed by using a weighted Fourier transform. Such experiments necessarily use flux from multiple reactors at distinct baselines, smearing the oscillation signal and thus impeding the determination of the hierarchy. Using the results of our simulations, we determine the optimal baselines and corre...

Ciuffoli, Emilio; Zhang, Xinmin

2013-01-01T23:59:59.000Z

292

An innovative tri-directional broadband piezoelectric energy harvester  

SciTech Connect (OSTI)

This paper presents a tri-directional piezoelectric energy harvester that is able to harvest vibration energy over a wide bandwidth from three orthogonal directions. The harvester consists of a main beam, an auxiliary beam, and a spring-mass system, with magnets integrated to introduce nonlinear force and couple the three sub-systems. Theoretical analysis and experiments were performed at constant acceleration under frequency sweeps to acquire frequency responses. The experimental results show that the voltage can achieve more than 2?V over more than 5?Hz of bandwidth with 1 M? load in the three orthogonal directions.

Su, Wei-Jiun, E-mail: weijiun@mie.utoronto.ca; Zu, Jean [Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, Ontario M5S 3G8 (Canada)] [Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, Ontario M5S 3G8 (Canada)

2013-11-11T23:59:59.000Z

293

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

294

Directives Quarterly Updates  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

Listings of new Justification Memoranda and new or revised Directives that have been posted to the DOE Directives, Delegations, and Requirements Portal. Updated quarterly.

295

Another face of DIRECT  

E-Print Network [OSTI]

authors, see for example, tree-Direct [5]. This paper ..... [4] J.M. Gablonsky, Modifications of the DIRECT Algorithm, Ph.D. Thesis, North Carolina State. University ...

chiter

2007-08-01T23:59:59.000Z

296

Guidelines for Working at Voltages < 240 Volts  

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

Guidelines for Working at Voltages < 240 Volts Guidelines for Working at Voltages < 240 Volts February 4, 2005---DRAFT NOTE: Working hot is a LAST ALTERNATIVE. Electrical hot work is defined as: Working on or near exposed conducting parts that are or might become energized at 50V or more. Refer to Electrical Safety Flowchart for Working On or Near Live Parts. Engineered methods to prevent exposed sources of 50V and greater are to be implemented wherever practical. Only QUALIFIED PERSONNEL {as defined in NFPA 70E Article 110.6(D) 2004 edition} as authorized by the CAT/supervisor/division can perform such work. Refer to Qualified Electrical Worker Flow Chart. Training requirements: ES&H 114 (LOTO) / ES&H 375 (NFPA 70E) / ES&H 371 (electrical worker) - Observe Electrical Safe Work Practices. Refer to

297

Optimal Distributed Voltage Regulation in Power Distribution Networks  

E-Print Network [OSTI]

In this paper, we address the problem of voltage regulation in power distribution networks with deep-penetration of distributed energy resources (DERs), e.g., renewable-based generation, and storage-capable loads such as plug-in hybrid electric vehicles. We cast the problem as an optimization program, where the objective is to minimize the losses in the network subject to constraints on bus voltage magnitudes, limits on active and reactive power injections, transmission line thermal limits and losses. We provide sufficient conditions under which the optimization problem can be solved via its convex relaxation. Using data from existing networks, we show that the conditions are expected to be satisfied by most networks. We also provide an efficient distributed algorithm to solve the problem. The algorithm is asynchronous, with a communication topology that is the same as the electrical network topology. We illustrate the algorithm's performance in the IEEE 34-bus and the 123-bus feeder test systems.

Lam, Albert Y S; Dominguez-Garcia, Alejandro; Tse, David

2012-01-01T23:59:59.000Z

298

In-medium effects for nuclear matter in the Fermi energy domain  

E-Print Network [OSTI]

We study nuclear stopping in central collisions for heavy-ion induced reactions in the Fermi energy domain, between $15$ and $100$ A\\,\\textrm{MeV}. Using the large dataset of exclusive measurements provided by the $4\\pi$ array \\emph{INDRA}, we determine the relative degree of stopping as a function of system mass and bombarding energy. We show that the stopping can be directly related to the transport properties in the nuclear medium. By looking specifically at free nucleons (here protons), we present for the first time a comprehensive body of experimental results concerning the mean free path, the nucleon-nucleon cross-section and in-medium effects in nuclear matter. It is shown that the mean free path exhibits a maximum at $\\lambda_{NN}=9.5 \\pm 2$ \\textrm{fm}, around $E_{inc}=35-40$ A\\,\\textrm{MeV} incident energy and decreases toward an asymptotic value $\\lambda_{NN}= 4.5 \\pm 1$ \\textrm{fm} at $E_{inc} = 100$ A\\,\\textrm{MeV}. After accounting for Pauli blocking of elastic nucleon-nucleon collisions, it is shown that the effective in-medium \\emph{NN} cross section is further reduced compared to the free value in this energy range. Therefore, in-medium effects cannot be neglected in the Fermi energy range. These results bring new fundamental inputs for microscopic descriptions of nuclear reactions in the Fermi energy domain.

O. Lopez; D. Durand; G. Lehaut; B. Borderie; M. F. Rivet; R. Bougault; E. Galichet; D. Guinet; N. Le Neindre; P. Marini; P. Napolitani; M. Pârlog; E. Rosato; G. Spadaccini; E. Vient; M. Vigilante

2014-09-02T23:59:59.000Z

299

Energetic Electron Transport In An Inhomogeneous Plasma Medium  

SciTech Connect (OSTI)

A review of the work carried out at IPR on energetic electron transport through an inhomogeneous plasma medium is presented in this article. A Generalized Electron Magnetohydrodynamic (G-EMHD) fluid model has been developed and employed for such studies. Novel observations such as (i) the trapping of electron current pulse structure in a high density plasma region, (ii) the formation of sharp magnetic field shock structures at the inhomogeneous plasma density layer (iii) and intense energy dissipation at the shock layer even in the collisionless limit are reported. The intense energy dissipation of the electron current pulse at the shock layer provides a mechanism whereby highly energetic electrons which are essentially collision-less can also successfully deposit their energy in a local region of the plasma. This is specially attractive as it opens up the possibility of heating a localized region of an overdense plasma (where lasers cannot penetrate) by highly energetic collision-less electrons. A direct application of this mechanism to Fast Ignition (FT) experiments is discussed.

Das, Amita [Institute for Plasma Research, Bhat Gandhinagar-382428 (India)

2010-11-23T23:59:59.000Z

300

Method for producing low and medium BTU gas from coal  

SciTech Connect (OSTI)

A process for producing low and medium BTU gas from carbonizable material is described which comprises: partly devolatizing the material and forming hot incandescent coke therefrom by passing a bed of the same part way through a hot furnace chamber on a first horizontally moving grate while supplying a sub-stoichiometric quantity of air to the same and driving the reactions: C + O/sub 2/ = CO/sub 2/; 2C + O/sub 2/ = 2CO discharging the hot incandescent coke from the end of the first grate run onto a second horizontally moving grate run below the first grate run in the same furnace chamber so as to form a bed thereon, the bed formed on the second grate run being considerably thicker than the bed formed on the first grate run, passing the hot incandescent coke bed on the second grate run further through the furnace chamber in a substantially horizontal direction while feeding air and stream thereto so as to fully burn the coke and in ratio of steam to air driving the following reactions: 2C + O/sub 2/ = 2CO; C + H/sub 2/O = H/sub 2/ + CO; C + 2H/sub 2/O = 2H/sub 2/ + CO/sub 2/; CO + H/sub 2/O = H/sub 2/ + CO/sub 2/ taking off the ash residue of the burned coke and taking off the gaseous products of the reactions.

Mansfield, V.; Francoeur, C.M.

1988-06-07T23:59:59.000Z

Note: This page contains sample records for the topic "direct medium voltage" 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

Reference Buildings by Building Type: Medium office  

Broader source: Energy.gov [DOE]

In addition to the ZIP file for each building type, you can directly view the "scorecard" spreadsheet that summarizes the inputs and results for each location. This Microsoft Excel spreadsheet is also included in the ZIP file. For version 1.4, only the IDF file is included.

302

Distribution capacitor automation that controls voltage and saves energy  

SciTech Connect (OSTI)

The Electric Distribution Business Line of Southern California Edison Company (SCE) has begun a program to improve the distribution system operations and electrical efficiency. The program, called the Distribution System Efficiency Enhancement Program (DSEEP), consists of five principal projects: Automated Switching, Circuit Lock-Out Alarming, Substation Monitoring and Control, Outage Management, and Distribution Capacitor Automation Project (DCAP). DCAP is the largest and most sophisticated of the projects being implemented. The project takes advantage of fine-tuning customer voltages for conservation voltage regulation (CVR) benefits as well as minimizes line losses by reducing unnecessary reactive power flow. DCAP can also help to increase transmission line and substation capacity by improving system power factor. The DCAP system takes advantage of the distributed processing capability of meters, capacitor controllers, radios, and substation processors. DCAP uses two-way packet radios and new electronic meters that read real-time customer voltages as well as energy consumption. The radios transmit customer meter voltage information and capacitor status to substation processors, where a control algorithm runs to determine which capacitors should be turned on or off. The objective of DCAP is to reduce over-all net energy transfer from the substation to the customer and meet system VAR requirements. SCE has tested the system on 66 circuit capacitors (including 3 substation capacitors) on 18 circuits served from two substations. The positive results of the DCAP demonstrations has led to an aggressive roll-out plan for system-wide implementation of automating over 7600 switched capacitors by year-end 1995.

Williams, B.R.

1994-12-31T23:59:59.000Z

303

Archive Reference Buildings by Building Type: Medium office | Department of  

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

Medium office Medium office Archive Reference Buildings by Building Type: Medium office Here you will find past versions of the reference buildings for new construction commercial buildings, organized by building type and location. A summary of building types and climate zones is available for reference. Current versions are also available. You can download ZIP files that contain the following: An EnergyPlus software input file (.idf) An html file showing the results from the EnergyPlus simulation (.html) A spreadsheet that summarizes the inputs and results for each location (.xls) The EnergyPlus TMY2 weather file (.epw). benchmark-v1.0_3.0-medium_office.zip benchmark-v1.1_3.1-medium_office.zip benchmark-new-v1.2_4.0-medium_office.zip More Documents & Publications Archive Reference Buildings by Building Type: Large office

304

Real time voltage control using emergency demand response in distribution system by integrating advanced metering infrastructure  

Science Journals Connector (OSTI)

In this paper an analytical study is reported to demonstrate the effects of demand response on distribution network voltages profile. Also a new approach for real time voltage control is proposed which uses emergency demand response program aiming at maintaining voltage profile in an acceptable range with minimum cost. This approach will be active in emergency conditions where in real time the voltages in some nodes leave their permissible ranges. These emergency conditions are Distributed Generation (DG) units and lines outage and unpredictable demand and renewable generations' fluctuations. The proposed approach does not need the load and renewable generation forecast data to regulate voltage. To verify the effectiveness and robustness of the proposed control scheme the proposed voltage control scheme is tested on a typical distribution network. The simulation results show the effectiveness and capability of the proposed real time voltage control model to maintain smart distribution network voltage in specified ranges in both normal and emergency conditions.

Alireza Zakariazadeh; Shahram Jadid

2014-01-01T23:59:59.000Z

305

Demand Response by Decentralized Device Control Based on Voltage Level  

Science Journals Connector (OSTI)

This paper introduces a distributed, self-organizing approach to load control based on voltage measurement. A local voltage measurement defines a Level of Service (LoS), which is balanced with the neighboring ...

Wilfried Elmenreich; Stefan Schuster

2014-01-01T23:59:59.000Z

306

Demand Side Management using VOLTAGE / DISTRIBUTION OPTIMIZATION Quality improvement & Peak reduction  

Science Journals Connector (OSTI)

In order to improve the quality of the electrical energy delivered at consumer households a Voltage Optimization Device (VOD) is introduced in each household. This device controls the output voltage accurately at...

N. H. M. Hofmeester; C. J. van de Water

1994-01-01T23:59:59.000Z

307

E-Print Network 3.0 - ac voltage standard Sample Search Results  

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

"volts, AC"), the "secondary" voltage is roughly 6 VAC. We shall use the "Universal Transformer... :" conversion of AC to DC You can use a diode to convert the AC voltage of the...

308

E-Print Network 3.0 - applied voltages ii Sample Search Results  

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

dc-link voltage error is applied to the fun... --In this paper, a new hybrid active power filter topology is presented. A higher-voltage, low-switching fre... - quency...

309

Advanced Gate Drive for the SNS High Voltage Converter Modulator  

SciTech Connect (OSTI)

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

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

2009-05-07T23:59:59.000Z

310

Linear inductive voltage adders (IVA) for advanced hydrodynamic radiography  

SciTech Connect (OSTI)

The electron beam which drifts through the multiple cavities of conventional induction linacs (LIA) is replaced in an IVA by a cylindrical metal conductor which extends along the entire length of the device and effectuates the addition of the accelerator cavity voltages. In the approach to radiography, the linear inductive voltage adder drives a magnetically immersed electron diode with a millimeter diameter cathode electrode and a planar anode/bremsstrahlung converter. Both anode and cathode electrodes are immersed in a strong (15--50 T) solenoidal magnetic field. The electron beam cross section is approximately of the same size as the cathode needle and generates a similar size, very intense x-ray beam when it strikes the anode converter. An IVA driven diode can produce electron beams of equal size and energy as a LIA but with much higher currents (40--50 kA versus 4--5 kA), simpler hardware and thus lower cost. The authors present here first experimental validations of the technology utilizing HERMES 3 and SABRE IVA accelerators. The electron beam voltage and current were respectively of the order of 10 MV and 40 kA. X-ray doses of up to 1 kR {at} 1 m and spot sizes as small as 1.7 mm (at 200 R doses) were measured.

Mazarakis, M.G.; Boyes, J.D.; Johnson, D.L. [and others

1998-09-01T23:59:59.000Z

311

Thermally-induced voltage alteration for integrated circuit analysis  

DOE Patents [OSTI]

A thermally-induced voltage alteration (TIVA) apparatus and method are disclosed for analyzing an integrated circuit (IC) either from a device side of the IC or through the IC substrate to locate any open-circuit or short-circuit defects therein. The TIVA apparatus uses constant-current biasing of the IC while scanning a focused laser beam over electrical conductors (i.e. a patterned metallization) in the IC to produce localized heating of the conductors. This localized heating produces a thermoelectric potential due to the Seebeck effect in any conductors with open-circuit defects and a resistance change in any conductors with short-circuit defects, both of which alter the power demand by the IC and thereby change the voltage of a source or power supply providing the constant-current biasing. By measuring the change in the supply voltage and the position of the focused and scanned laser beam over time, any open-circuit or short-circuit defects in the IC can be located and imaged. The TIVA apparatus can be formed in part from a scanning optical microscope, and has applications for qualification testing or failure analysis of ICs.

Cole, Jr., Edward I. (Albuquerque, NM)

2000-01-01T23:59:59.000Z

312

An Open Question about Dependency of Life Time of Hardware Components and Dynamic Voltage Scaling  

E-Print Network [OSTI]

Open question about Dependency of Life Time of Hardware Components and Dynamic Voltage Scaling (A primary idea)

Jaberi, Nasrin

2012-01-01T23:59:59.000Z

313

Limiting discharge voltage of a capacitive energy store in a subway car  

Science Journals Connector (OSTI)

A method is proposed for calculating the limiting discharge voltage of a capacitive energy store in a subway car.

G. G. Ryabtsev; I. A. Ermakov

2012-12-01T23:59:59.000Z

314

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

E-Print Network [OSTI]

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

Ellingson, Steven W.

315

Direct laser acceleration of electrons in free-space  

E-Print Network [OSTI]

Compact laser-driven accelerators are versatile and powerful tools of unarguable relevance on societal grounds for the diverse purposes of science, health, security, and technology because they bring enormous practicality to state-of-the-art achievements of conventional radio-frequency accelerators. Current benchmarking laser-based technologies rely on a medium to assist the light-matter interaction, which impose material limitations or strongly inhomogeneous fields. The advent of few cycle ultra-intense radially polarized lasers has materialized an extensively studied novel accelerator that adopts the simplest form of laser acceleration and is unique in requiring no medium to achieve strong longitudinal energy transfer directly from laser to particle. Here we present the first observation of direct longitudinal laser acceleration of non-relativistic electrons that undergo highly-directional multi-GeV/m accelerating gradients. This demonstration opens a new frontier for direct laser-driven particle accelerati...

Carbajo, Sergio; Wong, Liang Jie; Miller, R J Dwayne; Kärtner, Franz X

2015-01-01T23:59:59.000Z

316

Plug-In Hybrid Electric Medium Duty Commercial Fleet Demonstration...  

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

rravt068vssmiyasato2011o .pdf More Documents & Publications SCAQMD:Plug-In Hybrid Electric Medium-Duty Commercial Fleet Demonstration and Evaluation Plug-In Hybrid Electric...

317

Guidelines and Toolkits for Urban Transport Development in Medium...  

Open Energy Info (EERE)

practitioners in states and municipal governments who are concerned with urban transport development in medium-sized cities in India. In addition, officials within the central...

318

Radiation pressure of light in a refractive medium  

Science Journals Connector (OSTI)

The radiation pressure and energy density of light in a refractive medium is calculated in terms of the index of refraction of the medium. The factor equal to the cube of the index of refraction that occurs in the expressions for the energy density and pressure of light in a refractive medium is shown to arise from the basic thermodynamic nature of the photon system and from the volume dependence of the index of refraction. It is shown that a mechanical pressure exists in a refractive medium which is in equilibrium with the blackbody radiation of the vacuum.

Richard A. Weiss

1976-01-01T23:59:59.000Z

319

Direct detector for terahertz radiation  

DOE Patents [OSTI]

A direct detector for terahertz radiation comprises a grating-gated field-effect transistor with one or more quantum wells that provide a two-dimensional electron gas in the channel region. The grating gate can be a split-grating gate having at least one finger that can be individually biased. Biasing an individual finger of the split-grating gate to near pinch-off greatly increases the detector's resonant response magnitude over prior QW FET detectors while maintaining frequency selectivity. The split-grating-gated QW FET shows a tunable resonant plasmon response to FIR radiation that makes possible an electrically sweepable spectrometer-on-a-chip with no moving mechanical optical parts. Further, the narrow spectral response and signal-to-noise are adequate for use of the split-grating-gated QW FET in a passive, multispectral terahertz imaging system. The detector can be operated in a photoconductive or a photovoltaic mode. Other embodiments include uniform front and back gates to independently vary the carrier densities in the channel region, a thinned substrate to increase bolometric responsivity, and a resistive shunt to connect the fingers of the grating gate in parallel and provide a uniform gate-channel voltage along the length of the channel to increase the responsivity and improve the spectral resolution.

Wanke, Michael C. (Albuquerque, NM); Lee, Mark (Albuquerque, NM); Shaner, Eric A. (Albuquerque, NM); Allen, S. James (Santa Barbara, CA)

2008-09-02T23:59:59.000Z

320

Topology optimization-based distribution design of actuation voltage in static shape control of plates  

Science Journals Connector (OSTI)

This paper investigates the optimal spatial distribution of single-channel actuation voltage in static structural shape control problem. It is pointed out that single-channel actuation voltage input for shape control applications is of practical importance ... Keywords: Shape control, Single channel, Topology optimization, Voltage distribution

Zhan Kang; Liyong Tong

2008-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "direct medium voltage" 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

Impact of Wind Generation Variability on Voltage Profile of Radial Power Systems  

Science Journals Connector (OSTI)

This paper provides the results of a study conducted to assess the impacts of the "wind generation variability" on the voltage profile in a small-scale radial power system. The power network has been modeled using one of the well-known simulation programs ... Keywords: Wind Generation, Voltage Profile, Power Grids, Voltage Impacts, Minimum Singular Value, SSV index

M. O. Alruwaili; M. Y. Vaziri; S. Vadhva; S. Vaziri

2013-04-01T23:59:59.000Z

322

Statistical Estimation of Leakage-Induced Power Grid Voltage Drop Considering Within-Die Process Variations  

E-Print Network [OSTI]

Statistical Estimation of Leakage-Induced Power Grid Voltage Drop Considering Within-Die Process the power grid, the grid develops large voltage drops, which is an unavoidable background level of noise on the grid. We develop techniques for estimation of the statistics of the leakage-induced power grid voltage

Najm, Farid N.

323

Statistical Estimation of LeakageInduced Power Grid Voltage Drop Considering WithinDie Process Variations #  

E-Print Network [OSTI]

Statistical Estimation of Leakage­Induced Power Grid Voltage Drop Considering Within­Die Process the power grid, the grid develops large voltage drops, which is an unavoidable background level of noise on the grid. We develop techniques for estimation of the statistics of the leakage­induced power grid voltage

Najm, Farid N.

324

Statistical Estimation of Circuit Timing Vulnerability Due to Leakage-Induced Power Grid Voltage Drop  

E-Print Network [OSTI]

Statistical Estimation of Circuit Timing Vulnerability Due to Leakage-Induced Power Grid Voltage voltage drops on the power grid that can affect circuit timing. We propose a statistical analysis supply voltage to circuit devices is referred to as the power grid. The consequences of power grid

Najm, Farid N.

325

Low-Voltage Ride-Through Techniques for DFIG-Based Wind Turbines  

E-Print Network [OSTI]

Low-Voltage Ride-Through Techniques for DFIG-Based Wind Turbines: State-of-the-Art Review deals with low-voltage ride-through (LVRT) capability of wind turbines (WTs) and in particular those as to index some emerging solutions. Index Terms--Wind turbine, doubly-fed induction generator, low voltage

Paris-Sud XI, Université de

326

Research on fuzzy logic based dynamic boundary voltage and reactive power integrated control method  

Science Journals Connector (OSTI)

Aiming at the existing problems of conventional substation voltage and reactive power integrated control method, a new fuzzy logic based dynamic reactive power boundary voltage and reactive power integrated control method is proposed. Fuzzy logic control ... Keywords: dynamic boundary, fuzzy logic, reactive power, voltage

Zigang Xu; Fei Wang

2009-06-01T23:59:59.000Z

327

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

E-Print Network [OSTI]

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

Wu, Thomas

328

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

E-Print Network [OSTI]

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

Powell, Warren B.

329

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

E-Print Network [OSTI]

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

Catholic University of Chile (Universidad CatĂłlica de Chile)

330

Method and apparatus for high-efficiency direct contact condensation  

DOE Patents [OSTI]

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

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

1999-01-01T23:59:59.000Z

331

Method and apparatus for high-efficiency direct contact condensation  

DOE Patents [OSTI]

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

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

1999-07-20T23:59:59.000Z

332

Foreign Direct Investment  

Gasoline and Diesel Fuel Update (EIA)

Investment Investment Foreign Direct Investment Foreign Direct Investment Foreign Direct Investment in U.S. Energy in U.S. Energy in U.S. Energy in U.S. Energy in 1999 in 1999 in 1999 in 1999 June 2001 ii iii Contents Foreign Affiliates' Role in U.S. Energy Industry Operations ..............................................................................1 Foreign Direct Investment: The International Transactions Accounts ..............................................................8 U.S. Companies' Direct Investment Abroad in Energy ......................................................................................14 Conclusion...............................................................................................................................................................19

333

Electrically controlling the polarizing direction of a graphene polarizer  

SciTech Connect (OSTI)

We theoretically demonstrate a polarizer with an electrically controllable polarizing direction in the far infrared range using two orthogonal periodic arrays of graphene ribbons, which have different widths and are supported on a dielectric film placed on a thick piece of metal. The operation mechanism originates from the polarization-dependent resonant absorption of the two orthogonal graphene ribbons, which can be respectively controlled with different external bias voltages. The operation wavelength can be expanded to terahertz (THz) radiation.

Zhu, Z. H., E-mail: zzhwcx@163.com; Qin, S. Q. [College of Optoelectronic Science and Engineering, National University of Defense Technology, Changsha 410073 (China); State Key Laboratory of High Performance Computing, National University of Defense Technology, Changsha 410073 (China); Guo, C. C.; Liu, K.; Zhang, J. F.; Ye, W. M.; Yuan, X. D. [College of Optoelectronic Science and Engineering, National University of Defense Technology, Changsha 410073 (China)

2014-09-14T23:59:59.000Z

334

Direct determination of quantum efficiency of semiconducting films  

DOE Patents [OSTI]

Photovoltaic quantum efficiency of semiconductor samples is determined directly, without requiring that a built-in photovoltage be generated by the sample. Electrodes are attached to the sample so as to form at least one Schottky barrier therewith. When illuminated, the generated photocurrent carriers are collected by an external bias voltage impressed across the electrodes. The generated photocurrent is measured, and photovoltaic quantum efficiency is calculated therefrom.

Faughnan, Brian W. (Princeton, NJ); Hanak, Joseph J. (Lawrenceville, NJ)

1986-01-01T23:59:59.000Z

335

Fluid breakup during simultaneous two-phase flow through a three-dimensional porous medium  

E-Print Network [OSTI]

We use confocal microscopy to directly visualize the simultaneous flow of both a wetting and a non-wetting fluid through a model three-dimensional (3D) porous medium. We find that, for small flow rates, both fluids flow through unchanging, distinct, connected 3D pathways; in stark contrast, at sufficiently large flow rates, the non-wetting fluid is broken up into discrete ganglia. By performing experiments over a range of flow rates, using fluids of different viscosities, and with porous media having different geometries, we show that this transition can be characterized by a state diagram that depends on the capillary numbers of both fluids, suggesting that it is controlled by the competition between the viscous forces exerted on the flowing oil and the capillary forces at the pore scale. Our results thus help elucidate the diverse range of behaviors that arise in two-phase flow through a 3D porous medium.

Sujit S. Datta; Jean-Baptiste Dupin; David A. Weitz

2014-06-26T23:59:59.000Z

336

Optical quantum swapping in a coherent atomic medium  

E-Print Network [OSTI]

We propose to realize a passive optical quantum swapping device which allows for the exchange of the quantum fluctuations of two bright optical fields interacting with a coherent atomic medium in an optical cavity. The device is based on a quantum interference process between the fields within the cavity bandwidth arising from coherent population trapping in the atomic medium.

Aurelien Dantan

2011-10-03T23:59:59.000Z

337

The Application of Droop-Control in Distributed Energy Resources to Extend the Voltage Collapse Margin  

SciTech Connect (OSTI)

The growth in distributed energy resources has the potential to reduce system stresses caused by transmission grid congestion by supplying power and voltage regulation closer to load centers. However, the additional voltage regulation provided by these resources can mask the onset of voltage collapse. Local voltage support flattens the slope in the upper region of the power-voltage nose curve. Coordinating voltage-regulation behavior with the droop-control scheme in distributed resources improves the observation of voltage collapse margins. Incorporating distributed resource models in the continuation power flow analysis, allows the exploration of the power transfer gains by the application of distributed resources. The analysis provides insight to the impact of droop control on the behavior of the power-voltage curve and voltage collapse. The analysis is applied to a fixed speed induction generator wind farm with separate reactive compensation and the interconnection to the local power system. Results reveal that coordinating the droop control strategy allows the distributed resource to significantly increase the voltage collapse margin without hiding the threat of voltage stability problems.

Henry, Shawn D. [Florida State University; Rizy, D Tom [ORNL; Baldwin, Thomas L [Florida State University; Kueck, John D [ORNL; Li, Fangxing [ORNL

2008-01-01T23:59:59.000Z

338

Outdoor PV Module Degradation of Current-Voltage Parameters: Preprint  

SciTech Connect (OSTI)

Photovoltaic (PV) module degradation rate analysis quantifies the loss of PV power output over time and is useful for estimating the impact of degradation on the cost of energy. An understanding of the degradation of all current-voltage (I-V) parameters helps to determine the cause of the degradation and also gives useful information for the design of the system. This study reports on data collected from 12 distinct mono- and poly-crystalline modules deployed at the National Renewable Energy Laboratory (NREL) in Golden, Colorado. Most modules investigated showed < 0.5%/year decrease in maximum power due to short-circuit current decline.

Smith, R. M.; Jordan, D. C.; Kurtz, S. R.

2012-04-01T23:59:59.000Z

339

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

340

Voltage sensor with fiber Fabry-Perot interferometer  

E-Print Network [OSTI]

with smaller strain constants, a larger voltage must be applied to get a 2x round trip phase shift. Hence, a longer FFPI is needed to get higher resolution. 16 A plate type PZT was selected because it's more convenient to attach to a thermo-electric cooler... in electron-beam evaporation system, they can be spliced to uncoated fibers, which also have cleaved end surfaces. The basic configuration for this Siecor Model M 67 fusion splicer is shown in fig. 12. A electric arc is initiated between the electrodes...

Wann, Been-Huey

1992-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "direct medium voltage" 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

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

342

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

343

Open bottom mesons in hot asymmetric hadronic medium  

E-Print Network [OSTI]

The in-medium masses and optical potentials of $B$ and ${\\bar B}$ mesons are studied in an isospin asymmetric, strange, hot and dense hadronic environment using a chiral effective model. The chiral $SU(3)$ model originally designed for the light quark sector, is generalized to include the heavy quark sector ($c$ and $b$) to derive the interactions of the $B$ and $\\bar B$ mesons with the light hadrons. Due to large mass of bottom quark, we use only the empirical form of these interactions for the desired purpose, while treating the bottom degrees of freedom to be frozen in the medium. Hence, all medium effects are due to the in-medium interaction of the light quark content of these open-bottom mesons. Both $B$ and $\\bar B$ mesons are found to experience net attractive interactions in the medium, leading to lowering of their masses in the medium. The mass degeneracy of particles and antiparticles, ($B^+$, $B^-$) as well as ($B^0$, ${\\bar B}^0$), is observed to be broken in the medium, due to equal and opposite contributions from a vectorial Weinberg-Tomozawa interaction term. Addition of hyperons to the medium lowers further the in-medium mass for each of these four mesons, while a non-zero isospin asymmetry is observed to break the approximate mass degeneracy of each pair of isospin doublets. These medium effects are found to be strongly density dependent, and bear a considerably weaker temperature dependence. The results obtained in the present investigation are compared to predictions from the quark-meson coupling model, heavy meson effective theory, and the QCD Sum Rule approach.

Divakar Pathak; Amruta Mishra

2014-09-02T23:59:59.000Z

344

Direct/Indirect Costs  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

This chapter provides recommended categories for direct and indirect elements developed by the Committee for Cost Methods Development (CCMD) and describes various estimating techniques for direct and indirect costs.

1997-03-28T23:59:59.000Z

345

A CCD Camera with Electron Decelerator for Intermediate Voltage Electron Microscopy  

SciTech Connect (OSTI)

Electron microscopists are increasingly turning to Intermediate Voltage Electron Microscopes (IVEMs) operating at 300 - 400 kV for a wide range of studies. They are also increasingly taking advantage of slow-scan charge coupled device (CCD) cameras, which have become widely used on electron microscopes. Under some conditions CCDs provide an improvement in data quality over photographic film, as well as the many advantages of direct digital readout. However, CCD performance is seriously degraded on IVEMs compared to the more conventional 100 kV microscopes. In order to increase the efficiency and quality of data recording on IVEMs, we have developed a CCD camera system in which the electrons are decelerated to below 100 kV before impacting the camera, resulting in greatly improved performance in both signal quality and resolution compared to other CCDs used in electron microscopy. These improvements will allow high-quality image and diffraction data to be collected directly with the CCD, enabling improvements in data collection for applications including high-resolution electron crystallography, single-particle reconstruction of protein structures, tomographic studies of cell ultrastructure and remote microscope operation. This approach will enable us to use even larger format CCD chips that are being developed with smaller pixels.

Downing, Kenneth H; Downing, Kenneth H.; Mooney, Paul E.

2008-03-17T23:59:59.000Z

346

Directives System Manual  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

This Manual provides detailed requirements to supplement DOE O 251.1A, Directives System, dated 1-30-98.

1998-01-30T23:59:59.000Z

347

Methods, systems and apparatus for controlling third harmonic voltage when operating a multi-space machine in an overmodulation region  

SciTech Connect (OSTI)

Methods, system and apparatus are provided for controlling third harmonic voltages when operating a multi-phase machine in an overmodulation region. The multi-phase machine can be, for example, a five-phase machine in a vector controlled motor drive system that includes a five-phase PWM controlled inverter module that drives the five-phase machine. Techniques for overmodulating a reference voltage vector are provided. For example, when the reference voltage vector is determined to be within the overmodulation region, an angle of the reference voltage vector can be modified to generate a reference voltage overmodulation control angle, and a magnitude of the reference voltage vector can be modified, based on the reference voltage overmodulation control angle, to generate a modified magnitude of the reference voltage vector. By modifying the reference voltage vector, voltage command signals that control a five-phase inverter module can be optimized to increase output voltages generated by the five-phase inverter module.

Perisic, Milun; Kinoshita, Michael H; Ranson, Ray M; Gallegos-Lopez, Gabriel

2014-06-03T23:59:59.000Z

348

Evaluation of the electromagnetic effects due to direct lighting to nuclear explosive areas at Pantex. Final report  

SciTech Connect (OSTI)

This report summarizes the effort to quantify the electromagnetic environments in the nuclear explosive areas at Pantex due to direct lightning. The fundamental measure of the threat to nuclear safety is assumed to be the maximum voltage between any two points in an assembly area, which is then available for producing arcing or for driving current into critical subsystems of a nuclear weapon. This maximum voltage has been computed with simple analytical models and with three-dimensional finite-difference computer codes.

Merewether, K.O.; Chen, K.C.

1993-11-01T23:59:59.000Z

349

JC3 Medium Impact Assessment Bulletins | Department of Energy  

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

Medium Impact Medium Impact Assessment Bulletins JC3 Medium Impact Assessment Bulletins RSS December 4, 2012 V-039: Samsung and Dell printers Firmware Backdoor Unauthorized Access Vulnerability Samsung has issued a security advisory and an optional firmware update for all current Samsung networked laser printers and multifunction devices to enhance Simple Network Management Protocol (SNMP) security. November 30, 2012 V-037: Wireshark Multiple Bugs Let Remote Users Deny Service Several vulnerabilities were reported in Wireshark. November 29, 2012 V-036: EMC Smarts Network Configuration Manager Database Authentication Bypass Vulnerability Two vulnerabilities were reported in EMC Smarts Network Configuration Manager. November 27, 2012 V-034: RSA Adaptive Authentication (On-Premise) Input Validation Flaws

350

Electromagnetic field quantization in a linear dielectric medium  

E-Print Network [OSTI]

By modeling a dielectric medium with two independent reservoirs, i.e., electric and magnetic reservoirs, the electromagnetic field is quantized in a linear dielectric medium consistently. A Hamiltonian is proposed from which using the Heisenberg equations, not only the Maxwell equations but also the structural equations can be obtained. Using the Laplace transformation, the wave equation for the electromagnetic vector potential is solved in the case of a homogeneous dielectric medium. Some examples are considered showing the applicability of the model to both absorptive and nonabsorptive dielectrics.

F. Kheirandish; M. Amooshahi

2005-11-13T23:59:59.000Z

351

Evaporation-driven growth of large crystallized salt structures in a porous medium  

Science Journals Connector (OSTI)

Subflorescence refers to crystallized salt structures that form inside a porous medium. We report a drying experiment revealing major development of subflorescence in the dry region of the porous medium away from the liquid zone. Using a combination of image analyses and numerical computations, we show that the growth is directly correlated to the evaporation flux distribution along the boundary of the growing salt structure. This indicates that the salt is transported into the domain occupied by the salt structure in the porous medium up to the structure periphery, where salt deposition takes place. This is confirmed when a growing salt structure encounters dry subflorescence formed earlier during the drying process. The dry subflorescence is reimbibed and resumes its growth. The analysis also suggests that the solution within the growing subflorescence is in equilibrium with the crystallized salt wall. These results shed light on the growth mechanisms of subflorescence, a phenomenon that can play a fundamental role in several important issues such as carbon dioxide sequestration or salt weathering.

N. Sghaier; S. Geoffroy; M. Prat; H. Eloukabi; S. Ben Nasrallah

2014-10-14T23:59:59.000Z

352

DYNAMICAL FRICTION IN A GASEOUS MEDIUM WITH A LARGE-SCALE MAGNETIC FIELD  

SciTech Connect (OSTI)

The dynamical friction force experienced by a massive gravitating body moving through a gaseous medium is modified by sufficiently strong large-scale magnetic fields. Using linear perturbation theory, we calculate the structure of the wake generated by, and the gravitational drag force on, a body traveling in a straight-line trajectory in a uniformly magnetized medium. The functional form of the drag force as a function of the Mach number ({identical_to} V{sub 0}/c{sub s} , where V{sub 0} is the velocity of the body and c{sub s} is the sound speed) depends on the strength of the magnetic field and on the angle between the velocity of the perturber and the direction of the magnetic field. In particular, the peak value of the drag force is not near Mach number {approx}1 for a perturber moving in a sufficiently magnetized medium. As a rule of thumb, we may state that for supersonic motion, magnetic fields act to suppress dynamical friction; for subsonic motion, they tend to enhance dynamical friction. For perturbers moving along the magnetic field lines, the drag force at some subsonic Mach numbers may be stronger than at supersonic velocities. We also mention the relevance of our findings to black hole coalescence in galactic nuclei.

Sanchez-Salcedo, F. J., E-mail: jsanchez@astroscu.unam.mx [Instituto de Astronomia, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, 04510 Mexico City (Mexico)

2012-02-01T23:59:59.000Z

353

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

E-Print Network [OSTI]

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

Lanterman, Aaron

354

Electromagnetic radiation in a time-varying background medium  

E-Print Network [OSTI]

Analytical solutions are presented for the electromagnetic radiation by an arbitrary pulsed source into a homogeneous time-varying background medium. In the constant-impedance case an explicit radiation formula is obtained for the synchronous permittivity and permeability described by any positive function of time. As might be expected, such a medium introduces significant spectral shifts and spatio-temporal modulation, which are analized here for the linear and exponential time-variations of the medium parameters. In the varying-impedance case the solution is obtained for the fourth-order polynomial time-dependence of the permittivity. In addition to the spectral shifts and modulation this spatially homogeneous medium scatters the field introducing causal echoes at the receiver location.

Budko, Neil V

2009-01-01T23:59:59.000Z

355

Multiphase turbulent interstellar medium: some recent results from radio astronomy  

E-Print Network [OSTI]

The radio frequency 1.4 GHz transition of the atomic hydrogen is one of the important tracers of the diffuse neutral interstellar medium. Radio astronomical observations of this transition, using either a single dish telescope or an array interferometer, reveal different properties of the interstellar medium. Such observations are particularly useful to study the multiphase nature and turbulence in the interstellar gas. Observations with multiple radio telescopes have recently been used to study these two closely related aspects in greater detail. Using various observational techniques, the density and the velocity fluctuations in the Galactic interstellar medium was found to have a Kolmogorov-like power law power spectra. The observed power law scaling of the turbulent velocity dispersion with the length scale can be used to derive the true temperature distribution of the medium. Observations from a large ongoing atomic hydrogen absorption line survey have also been used to study the distribution of gas at d...

Roy, Nirupam

2015-01-01T23:59:59.000Z

356

Georgia Power - Small and Medium Scale Advanced Solar Initiative (GPASI)  

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

Georgia Power - Small and Medium Scale Advanced Solar Initiative Georgia Power - Small and Medium Scale Advanced Solar Initiative (GPASI) (Georgia) Georgia Power - Small and Medium Scale Advanced Solar Initiative (GPASI) (Georgia) < Back Eligibility Agricultural Commercial General Public/Consumer Installer/Contractor Institutional Local Government Multi-Family Residential Nonprofit Residential Schools State Government Savings Category Solar Buying & Making Electricity Program Info Start Date 03/01/2013 State Georgia Program Type Other Incentive Provider GPASI Project Manager '''''Note: The application process for the small and medium scale solar programs began on March 1, 2013 and will continue through March 11, 2013. If completed applications exceed program capacity limit of 45 megawatts (MW), a lottery will be conducted, with Georgia Public Service Commission

357

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

SciTech Connect (OSTI)

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

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

2010-01-01T23:59:59.000Z

358

Bright and fast voltage reporters across the visible spectrum via electrochromic FRET (eFRET)  

E-Print Network [OSTI]

We present a palette of brightly fluorescent genetically encoded voltage indicators (GEVIs) with excitation and emission peaks spanning the visible spectrum, sensitivities from 6 - 10% Delta F/F per 100 mV, and half-maximal response times from 1 - 7 ms. A fluorescent protein is fused to an Archaerhodopsin-derived voltage sensor. Voltage-induced shifts in the absorption spectrum of the rhodopsin lead to voltage-dependent nonradiative quenching of the appended fluorescent protein. Through a library screen, we identified linkers and fluorescent protein combinations which reported neuronal action potentials in cultured rat hippocampal neurons with a single-trial signal-to-noise ratio from 6.6 to 11.6 in a 1 kHz imaging bandwidth at modest illumination intensity. The freedom to choose a voltage indicator from an array of colors facilitates multicolor voltage imaging, as well as combination with other optical reporters and optogenetic actuators.

Zou, Peng; Douglass, Adam D; Hochbaum, Daniel R; Brinks, Daan; Werley, Christopher A; Harrison, D Jed; Campbell, Robert E; Cohen, Adam E

2014-01-01T23:59:59.000Z

359

Seismic vulnerability assessment of a high voltage disconnect switch  

Science Journals Connector (OSTI)

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

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

2014-01-01T23:59:59.000Z

360

Discriminator based on voltage comparator for nuclear physics research  

SciTech Connect (OSTI)

This paper describes a simple discriminator of low-level pulses with integral discrimination based on a K521SA3 comparator. The discriminator can be used to record pulses with durations of greater than or equal to 0.1 usec and amplitudes of greater than or equal to 1 mV. the input-pulse amplitude must not exceed the supply-voltage amplitude. A schematic diagram of the discriminator is given. For operation of the NGR spectrometer in the constant-velocity mode, the comparator was gated by the bipolar vibrator-velocity signal. The described circuit is reliable under laboratory conditions and its use is promising in multi-input systems such as those with multisection coordinate detectors.

Vorob'ev, V.A.; Kiselev, A.A.; Kuz'min, R.N.

1985-12-01T23:59:59.000Z

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


361

Effect of DC voltage pulses on memristor behavior.  

SciTech Connect (OSTI)

Current knowledge of memristor behavior is limited to a few physical models of which little comprehensive data collection has taken place. The purpose of this research is to collect data in search of exploitable memristor behavior by designing and implementing tests on a HP Labs Rev2 Memristor Test Board. The results are then graphed in their optimal format for conceptualizing behavioral patterns. This series of experiments has concluded the existence of an additional memristor state affecting the behavior of memristors when pulsed with positively polarized DC voltages. This effect has been observed across multiple memristors and data sets. The following pages outline the process that led to the hypothetical existence and eventual proof of this additional state of memristor behavior.

Evans, Brian R.

2013-10-01T23:59:59.000Z

362

Voltage flicker prediction for two simultaneously operated ac arc furnaces  

SciTech Connect (OSTI)

An EMTP-based arc furnace model was developed for evaluation of flicker concerns associated with supplying a large integrated steel mill as they go from one to two furnace operation and as system changes are implemented that will affect the short circuit capacity at the 230 kV power supply substation. The model includes a dynamic arc representation which is designed to be characteristic of the initial portions of the melt cycle when the arc characteristics are the most variable (worst flicker conditions). The flicker calculations are verified using previous measurements with one furnace operation. Flicker simulations were then performed to evaluate a variety of different possible system strengths with both one and two furnaces in operation. The primary flicker measure used for this study is the unweighted rms value of the fluctuation envelope, expressed as a percentage of the rms line-to-ground voltage magnitude.

Tang, L. [ABB Power T and D Co., Inc., Raleigh, NC (United States)] [ABB Power T and D Co., Inc., Raleigh, NC (United States); Kolluri, S. [Entergy Services, New Orleans, LA (United States)] [Entergy Services, New Orleans, LA (United States); McGranaghan, M.F. [Electrotek Concepts, Inc., Knoxville, TN (United States)] [Electrotek Concepts, Inc., Knoxville, TN (United States)

1997-04-01T23:59:59.000Z

363

Voltage spike detection in high field superconducting accelerator magnets  

SciTech Connect (OSTI)

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

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

2004-12-01T23:59:59.000Z

364

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

365

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

SciTech Connect (OSTI)

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

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

2008-01-01T23:59:59.000Z

366

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

367

Departmental Directives Program  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

To define requirements and responsibilities for implementing the Department of Energy (DOE) Directives Program in support of the Secretary's memorandum of September 10, 2007, Principles Governing Departmental Directives. See also the current list of Directives Requiring Further Documentation, as required by Appendix D of this Order. Cancels DOE P 251.1A, DOE O 251.1B, DOE M 251.1-1B.

2007-09-10T23:59:59.000Z

368

Sacramento Area Voltage Support Draft Environmental Impact Statement  

SciTech Connect (OSTI)

The Western Area Power Administration's Central Valley Project transmission system forms an integral part of the interconnected Sacramento area transmission grid. Western is contractually responsible to oversee that the system is operated in accordance with strict reliability standards. Growth in the greater Sacramento, California area and power imported from generation outside the region, have increased the demand on the interconnected electric transmission system, leading to transmission system overloads and reducing the reliability and security of the area power system. Western has prepared this Sacramento Area Voltage Support (SVS) Draft Environmental Impact Statement (EIS) in compliance with Federal laws, regulations and guidelines, principally the ''National Environmental Policy Act'' (NEPA). This Draft EIS evaluates the potential environmental effects of physical improvements to the area's power system. Enhancements are needed to improve system reliability and provide voltage support for the Sacramento area. The results of public scoping meetings, workshops, meetings with agencies, and earlier studies by Western and area utilities helped to develop a range of alternatives for analysis. The Proposed Action involves: Constructing a new double-circuit, 230-kV transmission line paralleling the existing double-circuit, 230-kV line from the O'Banion Substation to the Elverta Substation; Realigning a portion of the existing Cottonwood-Roseville single-circuit, 230-kV transmission line north of Elverta Substation; and Reconductoring the existing double-circuit, 230-kV transmission line from the Elverta Substation to the Tracy Substation. Public Hearings on the Draft EIS will be held between December 9-12, 2002. Comments on this Draft EIS are encouraged and should be sent to Ms. Loreen McMahon (above). Comments must be received by December 30, 2002.

N /A

2002-11-15T23:59:59.000Z

369

Sacramento Area Voltage Support Final Environmental Impact Statement  

SciTech Connect (OSTI)

The Western Area Power Administration's Central Valley Project transmission system forms an integral part of the interconnected Sacramento area transmission grid. Western is contractually responsible to oversee that the system is operated in accordance with strict reliability standards. Growth in the greater Sacramento, California area and power imported from generation outside the region, have increased the demand on the interconnected electric transmission system, leading to transmission system overloads and reducing the reliability and security of the area power system. Western has prepared this Sacramento Area Voltage Support (SVS) Draft Environmental Impact Statement (EIS) in compliance with Federal laws, regulations and guidelines, principally the National Environmental Policy Act (NEPA). This Draft EIS evaluates the potential environmental effects of physical improvements to the area's power system. Enhancements are needed to improve system reliability and provide voltage support for the Sacramento area. The results of public scoping meetings, workshops, meetings with agencies, and earlier studies by Western and area utilities helped to develop a range of alternatives for analysis. The Proposed Action involves: (1) Constructing a new double-circuit, 230-kV transmission line paralleling the existing double-circuit, 230-kV line from the O'Banion Substation to the Elverta Substation; (2) Realigning a portion of the existing Cottonwood-Roseville single-circuit, 230-kV transmission line north of Elverta Substation; and (3) Reconductoring the existing double-circuit, 230-kV transmission line from the Elverta Substation to the Tracy Substation. Public Hearings on the Draft EIS will be held between December 9-12, 2002. Comments on this Draft EIS are encouraged and should be sent to Ms. Loreen McMahon (above). Comments must be received by December 30, 2002.

N /A

2003-09-19T23:59:59.000Z

370

Directives System Manual  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

This Manual provides detailed requirements to supplement DOE O 251.1, which establishes requirements for the development, coordination, and sunset review of DOE directives.

1995-10-16T23:59:59.000Z

371

Departmental Directives Program  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

To establish directives as the primary means to set, communicate, and institutionalize policies, requirements, responsibilities, and procedures for Departmental elements and contractors.

2014-10-16T23:59:59.000Z

372

Investigation of dc precise voltage sources for use as Zener transport standard  

SciTech Connect (OSTI)

20 precise compact voltage sources based on zener diodes were manufactured. These sources were under investigation at measuring system in NPO VNIIFTRI during the year. A few sources with voltage drift less than 5 ppm per year and noise level lower than 100 nV in the frequency band of 0,01-10 Hz were selected for manufacturing of 4-channels dc voltage transportable reference standard. This reference standard was investigated by Russian 1-V Josephson systems.

Karpov, O.V.; Shulga, V.M.; Shakirzyanova, F.R. [National Scientifical and Research Institute for Physical Technical and Radiotechnical Measurements, Moscow (Russian Federation)

1994-12-31T23:59:59.000Z

373

February 2008 Rev 21 1/49 Very low drop voltage regulators with inhibit  

E-Print Network [OSTI]

. In the three terminal configuration the device has the same electrical performance, but is fixed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 4 Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Figure 4. Dropout voltage vs output current

Berns, Hans-Gerd

374

Object Oriented Safety Analysis of an Extra High Voltage Substation Bay  

Science Journals Connector (OSTI)

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

Bartosz Nowicki; Janusz Górski

1998-01-01T23:59:59.000Z

375

Dynamic voltage-current characteristics for a water jet plasma arc  

SciTech Connect (OSTI)

A virtual instrument technology is used to measure arc current, arc voltage, dynamic V-I characteristics, and nonlinear conductance for a cone-shaped water jet plasma arc under ac voltage. Experimental results show that ac arc discharge mainly happens in water vapor evaporated from water when heated. However, due to water's cooling effect and its conductance, arc conductance, reignition voltage, extinguish voltage, and current zero time are very different from those for ac arc discharge in gas work fluid. These can be valuable to further studies on mechanism and characteristics of plasma ac discharge in water, and even in gas work fluid.

Yang Jiaxiang; Lan Sheng; Xu Zuoming [College of Electrical and Electronic Engineering, Harbin University of Science and Technology, Harbin, Heilongjiang 150040 (China)

2008-05-05T23:59:59.000Z

376

Lab Trials of an Electricity Transmission Line Voltage Sensor Based on Thermally Poled Silica Fibre  

Science Journals Connector (OSTI)

Voltage sensing using helically coiled lengths of thermally poled twin-hole silica optical fibre is presented. Lab accuracy test results showing good linearity and signal to noise...

Michie, Andrew M; Hambley, Philip; Bassett, Ian M; Haywood, John H; Henry, Peter; Ingram, John

377

The design of an A-C voltage regulator using a Wein Bridge detector  

E-Print Network [OSTI]

equipment, which in turn demands a mox'e closely regulated power supply. In satisfying these demands there have been many kinds of voltage regulators designed, constructed, and needs A voltage regulator oonsists essentially of two pax'ts, the "detectox...-V, 424-8, 470 3, 499-503 1950 4. Patchett, G. N. , "The Theory of Nonlinear Bridge Circuit Applied to Voltage Stabilizers, " J. I . E. E . , Vol. 93, Pt. III, p. 18 (1948). 5. Choudbury, J. K. t Das Gupta, S. C. , and Sen, P. C, , "An A-C Voltage...

Brown, Richard True

2012-06-07T23:59:59.000Z

378

Solid State NMR Studies and Local Structure of Voltage Fade Materials  

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

with the Voltage Fade Team Michael Slater, Jason Croy, Kevin Gallagher, Christopher Johnson, Yang Ren DOE Vehicle Technologies Program Annual Merit Review Arlington, VA May 13 -...

379

Consideration of 34. 5 KV as an in-plant voltage for a large industrial user  

SciTech Connect (OSTI)

Traditionally, the in-plant distribution voltage for a large refinery or petrochemical complex has been 13.8 kV. Selection of this voltage level was dictated primarily by economic factors, simply because in most cases the magnitude of the loads or the lengths of the feeders did not produce sufficient savings to compensate for the costlier higher voltage switchgear. This paper presents some engineering and cost considerations for distribution at 34.5 kV and attempts to show that this voltage level is both economically and technically feasible for large electrical systems.

Niculescu, T.D.; Regan, R.R.

1983-09-01T23:59:59.000Z

380

E-Print Network 3.0 - affects voltage-gated calcium Sample Search...  

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

modulate neuronal voltage-gated calcium cur- rents, we performed a whole-cell patch... that hippocampal neurons in an astrocyte-enriched environment show augmentation of...

Note: This page contains sample records for the topic "direct medium voltage" 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

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

382

Abrupt Decline in the Open-Circuit Voltage of Direct Methanol Fuel Cells at Critical Oxygen Feed Rate  

E-Print Network [OSTI]

PEMFCs . In an effort to reduce methanol crossover, many researchers have sought either to develop new is more sluggish than that of hydrogen. Thus, more reactive electrocatalysts are desired.1,8,9 The second depresses the cathode potential as well as poisons the cathode electrocatalyst.2 In addition, the permeated

Zhao, Tianshou

383

Ripping Graphene: Preferred Directions  

Science Journals Connector (OSTI)

Ripping Graphene: Preferred Directions ... Here we present experimental and theoretical studies on cracks or tears in suspended monolayer graphene membranes. ... Edges from mechanically induced ripping exhibit straight lines and are predominantly aligned in the armchair or zigzag directions of the graphene lattice. ...

Kwanpyo Kim; Vasilii I. Artyukhov; William Regan; Yuanyue Liu; M. F. Crommie; Boris I. Yakobson; A. Zettl

2011-12-12T23:59:59.000Z

384

Departmental Directives System  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

The order establishes the directives system to be used for publishing permanent and temporary directives issued by DOE Headquarters and addressed to Headquarters and/or field elements. Chg 1 dated 3-14-85. Cancels DOE 1321.1A.

1983-04-07T23:59:59.000Z

385

direct_deposit_111609  

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

PROTECT YOUR BANKING INFORMATION: PROTECT YOUR BANKING INFORMATION: DO NOT complete this form until you are ready to submit it to the Payroll Department. DIRECT DEPOSIT REQUEST Directions: 1. Provide required information neatly, legibly; 2. If Checking Account Direct Deposit, include a voided check. a. DO NOT submit a deposit slip! 3. If Savings Account Direct Deposit, include a copy of savings card. 4. Sign this form; 5. Inter-office mail it to Craft Payroll at "P238." DIRECT DEPOSITION AUTHORIZATION I hereby authorize Los Alamos National Laboratory, hereinafter called The Laboratory, to initiate credit entries and, if necessary, debit entries and adjustments for any credit entries in error to my account listed on this form. If deposit is for:

386

Directions and Maps  

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

Directions & Maps Directions & Maps Plan Your Visit Visit About the Museum Museum Hours Directions & Maps When to Visit Arrange for a Visit Around Los Alamos Contact Us invisible utility element Directions and Maps Aerial View of Los Alamos Aerial approach to the Los Alamos airport Where we're located Los Alamos (elevation 7,355 feet) is perched high atop the Pajarito Plateau in the Jemez Mountains, 35 miles northwest of Santa Fe. The Bradbury Science Museum is located in downtown Los Alamos at the corner of Central Avenue and 15th Street. If you're driving here and using GPS navigation, our address is 1350 Central Avenue, Los Alamos, NM 87544. How to get here From Albuquerque take I-25 north to Santa Fe (take NM 599 for most direct route), then US 84/285 north to Pojoaque. At Pojoaque take the NM 502 exit

387

The Distribution of Pressures in a Supernova-Driven Interstellar Medium. I. Magnetized Medium  

E-Print Network [OSTI]

Observations have suggested substantial departures from pressure equilibrium in the interstellar medium (ISM) in the plane of the Galaxy, even on scales under 50 pc. Nevertheless, multi-phase models of the ISM assume at least locally isobaric gas. The pressure then determines the density reached by gas cooling to stable thermal equilibrium. We use numerical models of the magnetized ISM to examine the consequences of supernova driving for interstellar pressures. In this paper we examine a (200 pc)^3 periodic domain threaded by magnetic fields. Individual parcels of gas at different pressures reach widely varying points on the thermal equilibrium curve: no unique set of phases is found, but rather a dynamically-determined continuum of densities and temperatures. A substantial fraction of the gas remains entirely out of thermal equilibrium. Our results appear consistent with observations of interstellar pressures. They also suggest that the high pressures observed in molecular clouds may be due to ram pressures in addition to gravitational forces. Much of the gas in our model lies far from equipartition between thermal and magnetic pressures, with ratios ranging from 0.1 to $10^4$ and ratios of uniform to fluctuating magnetic field of 0.5--1. Our models show broad pressure probability distribution functions with log-normal functional forms produced by both shocks and rarefaction waves, rather than power-law distributions produced by isolated supernova remnants. The width of the distribution can be described quantitatively by a formula derived from the work of Padoan, Nordlund, & Jones (1997).

Mordecai-Mark Mac Low; Dinshaw S. Balsara; Jongsoo Kim; Miguel A. Avillez

2004-10-29T23:59:59.000Z

388

A Multilevel Voltage-Source Inverter with Separate DC Sources  

Office of Scientific and Technical Information (OSTI)

directly to a 13 kV power line. The corresponding parameters have been mentioned in Section IILC. The capacitances for the ten FBI units' dc capacitors are C,, C2, -,...

389

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

SciTech Connect (OSTI)

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

Long, W F

1981-01-01T23:59:59.000Z

390

Coupled numerical modelling of power loss generation in busbar system of low-voltage switchgear  

Science Journals Connector (OSTI)

Abstract This paper presents a coupled mathematical model of the heat transfer processes in an electric switchgear. The considered problem required the computation of the detailed distribution of the power losses and all the heat transfer modes (radiation, convection, and conduction) within a unit. In this complex thermal analysis, different definitions of electric busbar heating were considered and compared. The most advanced model, which couples the thermal and electromagnetic fields in two ways, was also compared with the simplified approaches. First, the direct current loading of the busbar, which neglected the alternating current effects, was considered. Second, models that included only one method of coupling were calculated for different assumed average busbar temperatures. Finally, the model with the two-way coupling, which took the eddy currents and proximity effects into account, was simulated using an iteration loop between the electromagnetic and fluid flow solvers. This study employed a geometrical model of industrial low-voltage switchgear. The presented mathematical model was also validated against temperature measurements carried out by a certified laboratory. The obtained results show that a fully coupled model produces very satisfactory agreement between computed and experimental data.

Mateusz Bedkowski; Jacek Smolka; Krzysztof Banasiak; Zbigniew Bulinski; Andrzej J. Nowak; Tomasz Tomanek; Adam Wajda

2014-01-01T23:59:59.000Z

391

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

SciTech Connect (OSTI)

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

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

2008-10-15T23:59:59.000Z

392

Heat transfer modeling at an interface between a porous medium and a free region.  

E-Print Network [OSTI]

??This work deals with the study of heat transfer between a porous medium and a free medium, using multi scale approaches. First, we derive the… (more)

D'hueppe, Aliénor

2011-01-01T23:59:59.000Z

393

E-Print Network 3.0 - areas medium sized Sample Search Results  

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

Medium... file with tables 12;Simulation Progress Modeled 802.15.4 Medium Access Control (MAC) and Physical Source: National Institute of Standards and Technology (NIST),...

394

E-Print Network 3.0 - alkaline medium peliculas Sample Search...  

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

rate: medium Texture: medium Foliage Leaf arrangement: alternate (Fig... requirement: tree grows in full sun Soil tolerances: clay; loam; sand; slightly alkaline; acidic;...

395

Medium Modifications of Hadron Properties and Partonic Processes  

E-Print Network [OSTI]

Chiral symmetry is one of the most fundamental symmetries in QCD. It is closely connected to hadron properties in the nuclear medium via the reduction of the quark condensate , manifesting the partial restoration of chiral symmetry. To better understand this important issue, a number of Jefferson Lab experiments over the past decade have focused on understanding properties of mesons and nucleons in the nuclear medium, often benefiting from the high polarization and luminosity of the CEBAF accelerator. In particular, a novel, accurate, polarization transfer measurement technique revealed for the first time a strong indication that the bound proton electromagnetic form factors in 4He may be modified compared to those in the vacuum. Second, the photoproduction of vector mesons on various nuclei has been measured via their decay to e+e- to study possible in-medium effects on the properties of the rho meson. In this experiment, no significant mass shift and some broadening consistent with expected collisional broadening for the rho meson has been observed, providing tight constraints on model calculations. Finally, processes involving in-medium parton propagation have been studied. The medium modifications of the quark fragmentation functions have been extracted with much higher statistical accuracy than previously possible.

W. K. Brooks; S. Strauch; K. Tsushima

2011-04-11T23:59:59.000Z

396

An Ensemble Empirical Mode Decomposition Approach for Voltage Sag Detection in a Smart Grid Context  

E-Print Network [OSTI]

An Ensemble Empirical Mode Decomposition Approach for Voltage Sag Detection in a Smart Grid Context Yassine Amirat1,2 , Mohamed Benbouzid2 , Tianzhen Wang3 and Sylvie Turri2 Abstract­Smart grids have become, using the instantaneous power for voltage sags detection in smart grids. Copyright © 2013 Praise Worthy

Brest, Université de

397

Hydroelectric Voltage Generation Based on Water-Filled Single-Walled Carbon Nanotubes  

Science Journals Connector (OSTI)

Hydroelectric Voltage Generation Based on Water-Filled Single-Walled Carbon Nanotubes ... The hydroelectric voltage generator can be expressed by the model illustrated in Figure 6a and b. ... Individual water-filled single-walled carbon nanotubes as hydroelectric power converters ...

Quanzi Yuan; Ya-Pu Zhao

2009-04-21T23:59:59.000Z

398

A genetic algorithm approach to voltage-VAR control in systems with distributed generation  

Science Journals Connector (OSTI)

This paper presents a case study that highlights the influences which the connection of distributed generation sources may have over the solutions of reactive power compensation and voltage control already existing in a given network. The problem of ... Keywords: distributed generation, genetic algorithms, renewable sources, voltage-var control

Iulia Coroama; Mihai Gavrilas; Ovidiu Ivanov

2010-10-01T23:59:59.000Z

399

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

E-Print Network [OSTI]

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

Najm, Farid N.

400

A Static PatternIndependent Technique for Power Grid Voltage Integrity Verification #  

E-Print Network [OSTI]

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

Najm, Farid N.

Note: This page contains sample records for the topic "direct medium voltage" 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

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

E-Print Network [OSTI]

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

402

Creation of Onset Voltage Hash by Anode Spots in a Magnetoplasmadynamic Thruster  

E-Print Network [OSTI]

Creation of Onset Voltage Hash by Anode Spots in a Magnetoplasmadynamic Thruster Luke Uribarri flow rate) of onset voltage fluctuations in a magnetoplasmadynamic thruster operating with three anode materials, and an anode spot model is presented which provides a physical explanation for the properties

Choueiri, Edgar

403

The Onset of Voltage Hash and its Relationship to Anode Spots in Magnetoplasmadynamic Thrusters  

E-Print Network [OSTI]

The Onset of Voltage Hash and its Relationship to Anode Spots in Magnetoplasmadynamic Thrusters, 08544 A phenomenological model is developed to elucidate the relationship between voltage hash and anode electromagnetic force density leads to a mass depletion in the anode region which, in turn, leads to a disparity

Choueiri, Edgar

404

Importance of the Equlibrium Node in Preventing the Voltage Collapse Occurs in the Wind Power System  

E-Print Network [OSTI]

Importance of the Equlibrium Node in Preventing the Voltage Collapse Occurs in the Wind Power collapse will occurs in a wind power system is discussed next. The method of power flow calculation is the specific analysis of a given simplified wind power system. Keywords--voltage collapse; Newton

Lavaei, Javad

405

Meter Any Wire, Anywhere by Virtualizing the Voltage Channel Thomas Schmid, David Culler, Prabal Dutta  

E-Print Network [OSTI]

Meter Any Wire, Anywhere by Virtualizing the Voltage Channel Thomas Schmid, David Culler, Prabal}@eecs.umich.edu culler@cs.berkeley.edu Abstract AC power meters require both voltage and current to be sampled physical proximity and fed into a single power metering de- vice. In this paper, we explore the viability

Dutta, Prabal

406

Onset Voltage Hash and Anode Spots in Quasi-Steady Magnetoplasmadynamic  

E-Print Network [OSTI]

Onset Voltage Hash and Anode Spots in Quasi-Steady Magnetoplasmadynamic Thrusters Luke Uribarri: Edgar Y. Choueiri November 2008 #12;ONSET VOLTAGE HASH AND ANODE SPOTS IN QUASI noise ("hash") and anode damage in a self-field, quasi-steady magnetoplasmadynamic thruster (MPDT

Choueiri, Edgar

407

Scaling of Anode Sheath Voltage Fall with the Operational Parameters in Applied-Field MPD  

E-Print Network [OSTI]

Scaling of Anode Sheath Voltage Fall with the Operational Parameters in Applied-Field MPD Thrusters (EPPDyL) Princeton University, Princeton, NJ, 08544, USA Scaling laws for the anode sheath voltage fall in applied-field MPD thrusters are derived in order to better understand the physics behind anode sheath

Choueiri, Edgar

408

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

E-Print Network [OSTI]

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

Pota, Himanshu Roy

409

Voltage Control of Distribution Networks with Distributed Generation using Reactive Power  

E-Print Network [OSTI]

Voltage Control of Distribution Networks with Distributed Generation using Reactive Power. Nasiruzzaman Abstract--Voltage profile of distribution networks with dis- tributed generation are affected significantly due to the integra- tion of distributed generation (DG) on it. This paper presents a way

Pota, Himanshu Roy

410

Energy Aware Dynamic Voltage and Frequency Selection for Real-Time Systems with Energy Harvesting  

E-Print Network [OSTI]

Energy Aware Dynamic Voltage and Frequency Selection for Real-Time Systems with Energy Harvesting}@binghamton.edu Abstract In this paper, an energy aware dynamic voltage and frequency selection (EA-DVFS) algorithm energy and the harvested energy in a future duration. Specifically, if the system has sufficient energy

Qiu, Qinru

411

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

Science Journals Connector (OSTI)

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

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

2003-01-01T23:59:59.000Z

412

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

E-Print Network [OSTI]

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

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

2015-01-01T23:59:59.000Z

413

DECENTRALIZED VOLTAGE CONTROL TO MINIMIZE DISTRIBUTION LOSSES IN AN ISLANDED MICROGRID  

E-Print Network [OSTI]

power sources and energy storage systems such as batteries requires new power and voltage control-time voltage control algorithm that minimizes power losses for a microgrid supported by inverter based Microgrids can bring electricity power to rural communities or isolated military forward operation bases

Peng, Huei

414

The activated state of a sodium channel voltage sensor in a membrane environment  

Science Journals Connector (OSTI)

...suggests a displacement of ?4 elementary charges per subunit across...voltage sensor reveals a focused electric field . Nature 427 ( 6974...CA Horn R ( 2005 ) Focused electric field across the voltage sensor of potassium...protease activity for protamine resistance of Escherichia coli . Arch...

Sudha Chakrapani; Pornthep Sompornpisut; Pathumwadee Intharathep; Benoît Roux; Eduardo Perozo

2010-01-01T23:59:59.000Z

415

Public Opinions of Building Additional High-Voltage Electric Power Lines  

E-Print Network [OSTI]

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

Tesfatsion, Leigh

416

A new technique to reject dc-link voltage ripple in PWM inverters  

E-Print Network [OSTI]

on the rlc-link, is numerically calculated. Let us assume, Inverfer output frequency f, ? 60 Hz Vs, = 1 pu Dc ? link voltage rrpple = k Vs, ? 0. 2 x Vge = . 2 pu Dc ? link voltage ripple frequency f, = 120 Hz :tfodulation index ? 0. 5 Frequency spectrum...

Shireen, Wajiha

1990-01-01T23:59:59.000Z

417

A Fully Directional Universal Power Electronic Interface for EV, HEV, and PHEV Applications  

SciTech Connect (OSTI)

This study focuses on a universal power electronic interface that can be utilized in any type of the electric vehicles, hybrid electric vehicles, and plug-in hybrid electric vehicles (PHEVs). Basically, the proposed converter interfaces the energy storage device of the vehicle with the motor drive and the external charger, in case of PHEVs. The proposed converter is capable of operating in all directions in buck or boost modes with a noninverted output voltage (positive output voltage with respect to the input) and bidirectional power flow.

Onar, Omer C [ORNL

2012-01-01T23:59:59.000Z

418

Supercritical Hadley circulation within a layer of fluid saturated porous medium: Bifurcation to traveling wave  

SciTech Connect (OSTI)

Hadley circulation induced by horizontal and vertical temperature gradients imposed on a fluid saturated porous medium layer is simulated numerically. The flow is assumed to be longitudinal, that is the secondary flow is composed of cells with axes transverse to the direction of the Hadley circulation. Critical (bifurcation) states predicted theoretically via linear stability analysis are verified by the numerical results giving confidence on the accuracy of the method. Several values of horizontal Rayleigh number, Ra{sub h}, and vertical Rayleigh number, Ra{sub v}, are studied. Results indicate that beyond a threshold horizontal Rayleigh number value the flow and temperature fields evolve from subcritical Hadley circulation to a supercritical time periodic flow. The secondary flow emerges in the form of a traveling wave aligned with the main (Hadley) flow direction. This traveling wave is characterized, at supercritical low vertical Rayleigh numbers, by the continuous drifting of two horizontal layers of flow cells that move in opposite directions. As the vertical Rayleigh number increases, the traveling wave becomes characterized by a unique layer of cells drifting in the direction opposite to the applied horizontal temperature gradient. Numerical animation unravels the main features of the transport process. This simplified model is of fundamental and practical importance, for instance, to the study of geothermal activities, underground transport of pollutants, paper processing, crystal growth, building insulation, and gas reservoirs.

Manole, D.M. [MCD Inc., Anniston, AL (United States); Lage, J.L.; Antohe, B.V. [Southern Methodist Univ., Dallas, TX (United States)

1995-12-31T23:59:59.000Z

419

Direct Discharge Permit (Vermont)  

Broader source: Energy.gov [DOE]

A direct discharge permit is required if a project involves the discharge of pollutants to state waters. For generation purposes, this involves the withdrawal of surface water for cooling purposes...

420

Directed transport in equilibrium  

E-Print Network [OSTI]

We investigate how a microscopic system, which can move only in one direction, comes to equilibrium with a heat-bath. To understand this problem, we investigate a symmetry broken dimer constrained to move in a particular direction when in contact with a uniform heat-bath at a constant temperature. The dimer is not driven by any external force. The system gains kinetic energy from the heat-bath and that the system can only use in directed transport. At the hard core collision limit between the particles of the dimer, we show by exact analytic calculations and complementary numerical results that the dimer undergoes steady directed transport by attaining a stationary distribution for a relevant degree of freedom. Our observation, being perfectly consistent with the {\\it second law of thermodynamics}, leads to a generalization of the existing {\\it Brownian ratchet} paradigm and points out some important limitations of {\\it Fokker-Planck} dynamics.

Bhattacharyay, A

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "direct medium voltage" 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

Surface Wind Direction Variability  

Science Journals Connector (OSTI)

Common large shifts of wind direction in the weak-wind nocturnal boundary layer are poorly understood and are not adequately captured by numerical models and statistical parameterizations. The current study examines 15 datasets representing a ...

Larry Mahrt

2011-01-01T23:59:59.000Z

422

Art Directable Tornadoes  

E-Print Network [OSTI]

......................................................................... 25 2. Directional Force ........................................................... 26 3. Vortex Force .................................................................. 26 4. Lattice... ................................................................... 7 7 Tornado in its rope stage before disappearing ........................................... 9 8 Fire vortex and Waterspout ........................................................................ 10 9 Landspout and Gustnado...

Dwivedi, Ravindra

2011-08-08T23:59:59.000Z

423

Training Manual for Micro, Small and Medium Entrepreneurs in Energy  

Open Energy Info (EERE)

Training Manual for Micro, Small and Medium Entrepreneurs in Energy Training Manual for Micro, Small and Medium Entrepreneurs in Energy Business Financing Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Training Manual for Micro, Small and Medium Entrepreneurs in Energy Business Financing Agency/Company /Organization: GVEP International Sector: Energy Focus Area: Renewable Energy, Non-renewable Energy Phase: Bring the Right People Together, Create a Vision, Determine Baseline, Evaluate Options, Develop Goals, Prepare a Plan Topics: Finance Resource Type: Training materials User Interface: Website Website: www.gvepinternational.org/sites/default/files/manual_for_sme_energy_fi Cost: Free UN Region: Eastern Africa Language: English The training manual is developed as a modular guide to enable energy entrepreneurs to acquire supplementary knowledge in order to expand their

424

Guidelines and Toolkits for Urban Transport Development in Medium Sized  

Open Energy Info (EERE)

Guidelines and Toolkits for Urban Transport Development in Medium Sized Guidelines and Toolkits for Urban Transport Development in Medium Sized Cities in India Jump to: navigation, search Tool Summary Name: Guidelines and Toolkits for Urban Transport Development in Medium Sized Cities in India Agency/Company /Organization: Asian Development Bank Focus Area: Governance - Planning - Decision-Making Structure Topics: Best Practices Complexity/Ease of Use: Not Available Website: sti-india-uttoolkit.adb.org/ Transport Toolkit Region(s): Asia Related Tools Promoting Clean Cars: Case Study of Stockholm and Sweden MOtor Vehicle Emission Simulator (MOVES) The World Bank - Transport ... further results Find Another Tool FIND TRANSPORTATION TOOLS This resource is designed to help decision makers and practitioners in states and municipal governments who are concerned with urban transport

425

JC3 Medium Impact Assessment Bulletins | Department of Energy  

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

Medium Impact Medium Impact Assessment Bulletins JC3 Medium Impact Assessment Bulletins RSS September 9, 2013 V-237: TYPO3 Security Bypass Vulnerabilities TYPO3 comes with the possibility to restrict editors to certain file actions (copy, delete, move etc.) and to restrict these actions to be performed in certain locations September 4, 2013 V-234: EMC RSA Archer GRC Open Redirection Weakness and Security Bypass Security Issue This fixes multiple vulnerabilities, which can be exploited to bypass certain security restrictions and to conduct spoofing attacks September 3, 2013 V-233: Red Hat update for JBoss Fuse This fixes multiple vulnerabilities, which can be exploited by malicious people to bypass certain security restrictions and cause a DoS. August 28, 2013 V-229: IBM Lotus iNotes Input Validation Flaws Permit Cross-Site Scripting

426

The role of the mobile medium in multichannel CRM communication  

Science Journals Connector (OSTI)

Research concerning the multichannel environment in different industries and contexts is increasing. However, the majority of studies fail to acknowledge the different characteristics of each individual channel. Therefore, this study takes a closer look at the mobile medium within the multichannel environment in CRM. More specifically, the purpose of this study is to examine the role of the mobile medium among other channels within multichannel CRM communication. Based on the purpose of the study, this research builds on an empirical single-case study in the airline industry. The findings of the study indicate that the mobile medium has an important, albeit complementary, role within multichannel CRM communication. The role is enhanced when the company takes into account the phase of the customer relationship and, moreover, the customers' travelling process.

Jaakko Sinisalo

2011-01-01T23:59:59.000Z

427

Quantum-mechanical description of in-medium fragmentation  

E-Print Network [OSTI]

We present a quantum-mechanical description of quark-hadron fragmentation in a nuclear environment. It employs the path-integral formulation of quantum mechanics, which takes care of all phases and interferences, and which contains all relevant time scales, like production, coherence, formation, etc. The cross section includes the probability of pre-hadron (colorless dipole) production both inside and outside the medium. Moreover, it also includes inside-outside production, which is a typical quantum-mechanical interference effect (like twin-slit electron propagation). We observe a substantial suppression caused by the medium, even if the pre-hadron is produced outside the medium and no energy loss is involved. This important source of suppression is missed in the usual energy-loss scenario interpreting the effect of jet quenching observed in heavy ion collisions. This may be one of the reasons of a too large gluon density, reported by such analyzes.

B. Z. Kopeliovich; H. -J. Pirner; I. K. Potashnikova; Ivan Schmidt; A. V. Tarasov; O. O. Voskresenskaya

2008-09-27T23:59:59.000Z

428

Medium Modifications of Hadron Properties and Partonic Processes  

E-Print Network [OSTI]

Chiral symmetry is one of the most fundamental symmetries in QCD. It is closely connected to hadron properties in the nuclear medium via the reduction of the quark condensate , manifesting the partial restoration of chiral symmetry. To better understand this important issue, a number of Jefferson Lab experiments over the past decade have focused on understanding properties of mesons and nucleons in the nuclear medium, often benefiting from the high polarization and luminosity of the CEBAF accelerator. In particular, a novel, accurate, polarization transfer measurement technique revealed for the first time a strong indication that the bound proton electromagnetic form factors in 4He may be modified compared to those in the vacuum. Second, the photoproduction of vector mesons on various nuclei has been measured via their decay to e+e- to study possible in-medium effects on the properties of the rho meson. In this experiment, no significant mass shift and some broadening consistent with expected collisional broa...

Brooks, W K; Tsushima, K

2011-01-01T23:59:59.000Z

429

Demand response medium sized industry consumers (Smart Grid Project) | Open  

Open Energy Info (EERE)

response medium sized industry consumers (Smart Grid Project) response medium sized industry consumers (Smart Grid Project) Jump to: navigation, search Project Name Demand response medium sized industry consumers Country Denmark Headquarters Location Aarhus, Denmark Coordinates 56.162937°, 10.203921° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":56.162937,"lon":10.203921,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

430

Feature - Fuel Economy for Medium- and Heavy-Duty Vehicles  

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

New Report Looks at Fuel Economy for Medium- and Heavy-Duty Vehicles New Report Looks at Fuel Economy for Medium- and Heavy-Duty Vehicles heavy duty trucks Argonne researcher Aymeric Rousseau was part of a National Academy of Science (NAS) committee established to make recommendations on improving and regulating fuel consumption for medium- and heavy-duty vehicles. On March 31, the committee issued a report that evaluates various technologies and methods that could improve the fuel economy of these vehicles. As a system analysis engineer at Argonne's Center for Transportation Research, Rousseau contributed his expertise on vehicle modeling and simulation to the committee, which was comprised of 19 members from industry, research organizations and academia. Rousseau, who leads the development of Argonne's PSAT and Autonomie software tools, helped the committee determine how modeling and simulation tools can be used to:

431

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

432

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

433

Refrigerant directly cooled capacitors  

DOE Patents [OSTI]

The invention is a direct contact refrigerant cooling system using a refrigerant floating loop having a refrigerant and refrigeration devices. The cooling system has at least one hermetic container disposed in the refrigerant floating loop. The hermetic container has at least one electronic component selected from the group consisting of capacitors, power electronic switches and gating signal module. The refrigerant is in direct contact with the electronic component.

Hsu, John S. (Oak Ridge, TN); Seiber, Larry E. (Oak Ridge, TN); Marlino, Laura D. (Oak Ridge, TN); Ayers, Curtis W. (Kingston, TN)

2007-09-11T23:59:59.000Z

434

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

435

Determination of the inductance of imploding wire array Z-pinches using measurements of load voltage  

SciTech Connect (OSTI)

The inductance of imploding cylindrical wire array z-pinches has been determined from measurements of load voltage and current. A thorough analysis method is presented that explains how the load voltage of interest is found from raw signals obtained using a resistive voltage divider. This method is applied to voltage data obtained during z-pinch experiments carried out on the MAGPIE facility (1.4 MA, 240 ns rise-time) in order to calculate the load inductance and thereafter the radial trajectory of the effective current sheath during the snowplough implosion. Voltage and current are monitored very close to the load, allowing these calculations to be carried out without the need for circuit modelling. Measurements give a convergence ratio for the current of between 3.1 and 5.7 at stagnation of the pinch.

Burdiak, G. C.; Lebedev, S. V.; Hall, G. N.; Harvey-Thompson, A. J.; Suzuki-Vidal, F.; Swadling, G. F.; Khoory, E.; Pickworth, L.; Bland, S. N.; Grouchy, P. de; Skidmore, J. [Blackett Laboratory, Imperial College, London SW7 2BW (United Kingdom)

2013-03-15T23:59:59.000Z

436

New Directions in Direct Dark Matter Searches  

E-Print Network [OSTI]

I present the status of direct dark matter detection with specific attention to the experimental results and their phenomenological interpretation in terms of dark matter interactions. In particular I review a new and more general approach to study signals in this field based on non-relativistic operators which parametrize more efficiently the dark matter-nucleus interactions in terms of a very limited number of relevant degrees of freedom. Then I list the major experimental results, pointing out the main uncertainties that affect the theoretical interpretation of the data. Finally, since the underlying theory that describes both the dark matter and the standard model fields is unknown, I address the uncertainties coming from the nature of the interaction. In particular, the phenomenology of a class of models in which the interaction between dark matter particles and target nuclei is of a long-range type is discussed.

Paolo Panci

2014-02-06T23:59:59.000Z

437

Advances and new directions in direct liquefaction  

SciTech Connect (OSTI)

With advance in single stage processes such as H-Coal, EDS and SRC, and refining and upgrading of coal liquids by Chevron and UOP, the direct liquefaction process has continuously evolved to the present two-stage catalytic configuration, which produces the highest liquid yield and product quality of any process worldwide. The Two Stage Liquefaction (TSL) process has been successfully applied to bituminous and subbituminous coals, overcoming problems associated with earlier processes. But, potential for additional improvement is recognized in several areas: cleaning coal prior to liquefaction; low temperature and pressure preconditioning of feed coal; novel catalysts development to arrest regressive reactions and improve hydrotreatment and cracking reactions; improvement in hydrocarbon value recovery and reduced energy rejection by alternate bottoms processing techniques. In this paper, after discussing briefly the history of liquefaction and development of the TSL process, present potential areas for research and development are presented.

Rao, S.N.; Schindler, H.D.; McGurl, G.V.

1988-01-01T23:59:59.000Z

438

Definition: Direct-Current Resistivity Survey | Open Energy Information  

Open Energy Info (EERE)

form form View source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Definition Edit with form History Facebook icon Twitter icon » Definition: Direct-Current Resistivity Survey Jump to: navigation, search Dictionary.png Direct-Current Resistivity Survey Direct-current (DC) resistivity is an active source electrical technique in which current is applied to the ground using electrodes and the earth response (voltage or potential difference) is recorded. This survey generates a geoelectric section of apparent resistivity and enables an inference of subsurface geology.[1] View on Wikipedia Wikipedia Definition References ↑ http://www.nga.com/Flyers_PDF/NGA_DC_Resistivity.pdf

439

Increasing the Competitiveness of Small and Medium-sized Enterprises  

Open Energy Info (EERE)

Page Page Edit with form History Facebook icon Twitter icon » Increasing the Competitiveness of Small and Medium-sized Enterprises Through the Use of Environmentally Sound Technologies Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Increasing the Competitiveness of Small and Medium-sized Enterprises Through the Use of Environmentally Sound Technologies: : Assessing the Potential for the Development of Second-generation Biofuels in the ESCWA Region Agency/Company /Organization: United Nations Economic and Social Commission for Western Asia Sector: Energy Focus Area: Renewable Energy, Biomass Topics: Market analysis, Policies/deployment programs, Background analysis, Technology characterizations Resource Type: Guide/manual, Lessons learned/best practices

440

Medium effects and jet fragmentation at the LHC  

SciTech Connect (OSTI)

In this work we study the production of charged hadrons in ultrarelativistic heavy ion collisions. We quantify the medium effects by calculating the nuclear ratio R{sub AA} as a function of the transverse momentum of the produced hadron. The main ingredients are the shadowing of the nuclear parton distributions, the jet energy loss and the fragmentation functions modified by the hot and dense medium. Our results are focused on the interplay of the different effects, and results are compared with recent LHC data.

Martins, S.; Mariotto, C. B.; Mackedanz, L. F. [Instituto de Matematica, Estatistica e Fisica, Universidade Federal do Rio Grande, Caixa Postal 474, CEP 96203-900, Rio Grande, RS (Brazil)

2013-03-25T23:59:59.000Z

Note: This page contains sample records for the topic "direct medium voltage" 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

Impact of Increasing Distributed Wind Power and Wind Turbine Siting on Rural Distribution Feeder Voltage Profiles: Preprint  

SciTech Connect (OSTI)

Many favorable wind energy resources in North America are located in remote locations without direct access to the transmission grid. Building transmission lines to connect remotely-located wind power plants to large load centers has become a barrier to increasing wind power penetration in North America. By connecting utility-sized megawatt-scale wind turbines to the distribution system, wind power supplied to consumers could be increased greatly. However, the impact of including megawatt-scale wind turbines on distribution feeders needs to be studied. The work presented here examined the impact that siting and power output of megawatt-scale wind turbines have on distribution feeder voltage. This is the start of work to present a general guide to megawatt-scale wind turbine impact on the distribution feeder and finding the amount of wind power that can be added without adversely impacting the distribution feeder operation, reliability, and power quality.

Allen, A.; Zhang, Y. C.; Hodge, B. M.

2013-09-01T23:59:59.000Z

442

Energy Efficiency Programs for Small and Medium Sized Industry  

E-Print Network [OSTI]

site. In this paper, we will examine the ways in which decisions are made in small and medium-sized facilities. A review of existing energy efficiency programs geared toward this sector will be analyzed. We will look into some of the failures...

Shipley, A. M.; Elliott, R. N.

443

Isotope Effects and Medium Effects on Sulfuryl Transfer Reactions  

Science Journals Connector (OSTI)

Kinetic isotope effects and medium effects have been measured for sulfuryl-transfer reactions of the sulfate ester p-nitrophenyl sulfate (pNPS). The results are compared to those from previous studies of phosphoryl transfer, a reaction with mechanistic ...

Richard H. Hoff; Paul Larsen; Alvan C. Hengge

2001-08-30T23:59:59.000Z

444

Medium Term Planning & Scheduling under Uncertainty for BP Chemicals  

E-Print Network [OSTI]

for PTA PX. From crude oil to PTA From crude oil to PX Production Chains: Products & Applications Models for planning medium term operations Monthly production Inventory targets What proportion of demand should be satisfied from which inventory location ? Types of businesses: PX PTA Deterministic model represents: Global

Grossmann, Ignacio E.

445

Distributed Medium Access Control for Next Generation CDMA Wireless Networks  

E-Print Network [OSTI]

Distributed Medium Access Control for Next Generation CDMA Wireless Networks Hai Jiang, Princeton wireless networks are expected to have a simple infrastructure with distributed control. In this article, we consider a generic distributed network model for future wireless multi- media communications

Zhuang, Weihua

446

In-medium antikaon interactions and bound states  

E-Print Network [OSTI]

Correct treatment of subthreshold Kbar-N dynamics is mandatory in kaonic-atom and Kbar-nuclear bound-state calculations, as demonstrated by using in-medium chirally-based models of Kbar-N interactions. Recent studies of kaonic-atom data reveal appreciable multi-nucleon contributions. Kbar-nuclear widths larger than 50 MeV are anticipated.

Avraham Gal; Eli Friedman; Nir Barnea; Aleš Cieplý; Ji?í Mareš; Daniel Gazda

2014-11-05T23:59:59.000Z

447

In-medium antikaon interactions and bound states  

E-Print Network [OSTI]

Correct treatment of subthreshold Kbar-N dynamics is mandatory in kaonic-atom and Kbar-nuclear bound-state calculations, as demonstrated by using in-medium chirally-based models of Kbar-N interactions. Recent studies of kaonic-atom data reveal appreciable multi-nucleon contributions. Kbar-nuclear widths larger than 50 MeV are anticipated.

Gal, Avraham; Barnea, Nir; Cieplý, Aleš; Mareš, Ji?í; Gazda, Daniel

2014-01-01T23:59:59.000Z

448

Effect of current compliance and voltage sweep rate on the resistive switching of HfO{sub 2}/ITO/Invar structure as measured by conductive atomic force microscopy  

SciTech Connect (OSTI)

The electrical characterization of HfO{sub 2}/ITO/Invar resistive switching memory structure was studied using conductive atomic force microscopy (AFM) with a semiconductor parameter analyzer, Agilent 4156C. The metal alloy Invar was used as the metal substrate to ensure good ohmic contact with the substrate holder of the AFM. A conductive Pt/Ir AFM tip was placed in direct contact with the HfO{sub 2} surface, such that it acted as the top electrode. Nanoscale current-voltage (I-V) characteristics of the HfO{sub 2}/ITO/Invar structure were measured by applying a ramp voltage through the conductive AFM tip at various current compliances and ramp voltage sweep rates. It was found that the resistance of the low resistance state (RLRS) decreased with increasing current compliance value, but resistance of high resistance state (RHRS) barely changed. However, both the RHRS and RLRS decreased as the voltage sweep rate increased. The reasons for this dependency on current compliance and voltage sweep rate are discussed.

Wu, You-Lin, E-mail: ylwu@ncnu.edu.tw; Liao, Chun-Wei [Department of Electrical Engineering, National Chi Nan University, Puli, Nantou, Taiwan (China); Ling, Jing-Jenn [Department of Applied Materials and Optoelectronic Engineering, National Chi Nan University, Puli, Nantou, Taiwan (China)

2014-06-16T23:59:59.000Z

449

First Direct Imaging of Swollen Microgel Particles  

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

First Direct Imaging of Swollen Microgel Particles Print First Direct Imaging of Swollen Microgel Particles Print Microgels are soft-material particles consisting of cross-linked polymer networks, 100 nm to 1 ÎĽm in diameter, dispersed in a continuous medium such as water. A useful feature of certain types of microgel particles is that they can swell or shrink with changes in external triggers such as pH and temperature. Thus microgel particles can act like "nanosponges" and offer many potential applications in medicine, environmental science, and industry. Because microgels are usually employed in their swollen state, in situ characterization of these particles under such conditions is desirable for understanding their behavior. However, optical microscopy is inadequate to this task, being limited in resolution and by the very small difference in refractive index (i.e., contrast) between the swollen particles and the continuous phase. Now, an international team of researchers from the U.S. and U.K. have obtained the first images of swollen microgel particles directly in aqueous solution using x-ray microscopy at the ALS, which, together with spectroscopic determination of their chemical state, provides insight into the underlying swelling mechanism.

450

First Direct Imaging of Swollen Microgel Particles  

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

First Direct Imaging of Swollen Microgel Particles Print First Direct Imaging of Swollen Microgel Particles Print Microgels are soft-material particles consisting of cross-linked polymer networks, 100 nm to 1 ÎĽm in diameter, dispersed in a continuous medium such as water. A useful feature of certain types of microgel particles is that they can swell or shrink with changes in external triggers such as pH and temperature. Thus microgel particles can act like "nanosponges" and offer many potential applications in medicine, environmental science, and industry. Because microgels are usually employed in their swollen state, in situ characterization of these particles under such conditions is desirable for understanding their behavior. However, optical microscopy is inadequate to this task, being limited in resolution and by the very small difference in refractive index (i.e., contrast) between the swollen particles and the continuous phase. Now, an international team of researchers from the U.S. and U.K. have obtained the first images of swollen microgel particles directly in aqueous solution using x-ray microscopy at the ALS, which, together with spectroscopic determination of their chemical state, provides insight into the underlying swelling mechanism.

451

First Direct Imaging of Swollen Microgel Particles  

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

Direct Imaging of Swollen Microgel Particles Print Direct Imaging of Swollen Microgel Particles Print Microgels are soft-material particles consisting of cross-linked polymer networks, 100 nm to 1 ÎĽm in diameter, dispersed in a continuous medium such as water. A useful feature of certain types of microgel particles is that they can swell or shrink with changes in external triggers such as pH and temperature. Thus microgel particles can act like "nanosponges" and offer many potential applications in medicine, environmental science, and industry. Because microgels are usually employed in their swollen state, in situ characterization of these particles under such conditions is desirable for understanding their behavior. However, optical microscopy is inadequate to this task, being limited in resolution and by the very small difference in refractive index (i.e., contrast) between the swollen particles and the continuous phase. Now, an international team of researchers from the U.S. and U.K. have obtained the first images of swollen microgel particles directly in aqueous solution using x-ray microscopy at the ALS, which, together with spectroscopic determination of their chemical state, provides insight into the underlying swelling mechanism.

452

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

Broader source: Energy.gov [DOE]

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

453

Source of Sustained Voltage Difference between the Xylem of a Potted Ficus benjamina Tree and Its Soil  

E-Print Network [OSTI]

It has long been known that there is a sustained electrical potential (voltage) difference between the xylem of many plants

Mershin, Andreas

454

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

SciTech Connect (OSTI)

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

N. Greenough, E. Fredd, S. DePasquale

2009-09-21T23:59:59.000Z

455

Monitoring voltage collapse margin with synchrophasors across transmission corridors with multiple lines and multiple contingencies  

E-Print Network [OSTI]

We use synchrophasor measurements of the complex voltage and current at both ends of multiple transmission lines that connect areas of a power system to monitor the online voltage collapse margin. A new reduction is used to reduce the multiple transmission lines to a single line equivalent and determine how to combine the synchrophasor measurements. Generator reactive power limits can be accommodated. The results show that this methodology can capture the effect of multiple contingencies inside the transmission corridors, giving awareness to the operators about the severity of contingencies with respect to voltage stability.

Ramirez, Lina

2014-01-01T23:59:59.000Z

456

Directional gamma detector  

DOE Patents [OSTI]

An improved directional gamma radiation detector has a collector sandwiched etween two layers of insulation of varying thicknesses. The collector and insulation layers are contained within an evacuated casing, or emitter, which releases electrons upon exposure to gamma radiation. Delayed electrons and electrons entering the collector at oblique angles are attenuated as they pass through the insulation layers on route to the collector.

LeVert, Francis E. (Downers Grove, Knoxville, TN); Cox, Samson A. (Downers Grove, IL)

1981-01-01T23:59:59.000Z

457

Extension of DOE Directives  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

This Notice extends the following directives until 2/16/04: DOE N 205.2, Foreign National Access to DOE Cyber Systems, and DOE N 205.3, Password Generation, Protection, and Use, dated 11/23/99-7/1/00.

2003-02-24T23:59:59.000Z

458

Laser-induced heating of a multilayered medium resting on a half-space: Part 2 - Moving source  

SciTech Connect (OSTI)

Direct access storage devices (DASDs) are widely used in the computer industry to store and manage data. In conventional magnetic recording, an induction head flying very close to the disk surface alters the polarization of the magnetic field of the disk surface to erase and or write the information on the disk. However, a new technology known as magneto optical recording or optical recording has considerable promise to increase data densities and reliability of data source. In magneto-optical storage, magnetic fields are altered by a laser source, which heats the magnetic medium beyond its Curie point, a temperature at which the magnetic medium loses its magnetization. This domain with zero magnetization is subsequently reversed by using an induction magnet. All these processes take place when the disk is rotating at a very high speed with respect to the laser source. An optical disk is a multilayered medium consisting of a thick glass disk on which many layers of different materials are sputtered, only one layer of which serves as a magnetic medium. Therefore, in this paper, a problem of laser-induced heating of a multilayered medium resting on a half-space is considered when the laser is translation with respect to it. The transient heat conduction equation is solved by employing the Laplace transform in the time domain and the Fourier Transform in the x, y dimension. The resulting ordinary differential equation is solved and the inversion of the Lapplace transform is obtained by a technique developed by Crump. The Fourier inversion is obtained by using a Fast Fourier Transform. The technique developed here is then applied to calculate domain size for recorded bits for a given disk, laser power, source characteristics, and rotational velocity.

Kant, R.; Deckert, K.L. (IBM Research Div., San Jose, CA (USA))

1991-02-01T23:59:59.000Z

459

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

Science Journals Connector (OSTI)

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

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

2014-01-01T23:59:59.000Z

460

Dynamic synchrotron X-ray imaging study of effective temperature in a vibrated granular medium  

E-Print Network [OSTI]

We present a dynamic synchrotron X-ray imaging study of the effective temperature $T_{eff}$ in a vibrated granular medium. By tracking the directed motion and the fluctuation dynamics of the tracers inside, we obtained $T_{eff}$ of the system using Einstein relation. We found that as the system unjams with increasing vibration intensities $\\Gamma$, the structural relaxation time $\\tau$ increases substantially which can be fitted by an Arrhenius law using $T_{eff}$. And the characteristic energy scale of structural relaxation yielded by the Arrhenius fitting is $E = 0.21 \\pm 0.02$ $pd^3$, where $p$ is the pressure and $d$ is the background particle diameter, which is consistent with those from hard sphere simulations in which the structural relaxation happens via the opening up of free volume against pressure.

Yixin Cao; Xiaodan Zhang; Binquan Kou; Xiangting Li; Xianghui Xiao; Kamel Fezzaa; Yujie Wang

2014-03-21T23:59:59.000Z

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


461

Letter: Direction and Guidance for Implementing Direct DOE Relationship &  

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

Letter: Direction and Guidance for Implementing Direct DOE Letter: Direction and Guidance for Implementing Direct DOE Relationship & Funding for EMSSABs Letter: Direction and Guidance for Implementing Direct DOE Relationship & Funding for EMSSABs From: Assistant Secretary, Jessie Hill Roberson (EM-11) To: Mr. Monte Wilson, Chair, INEEL Citizens Advisory Board This letter is in response to a November 21, 2003 letter regarding direction and guidance for implementing direct DOE relationship and funding for Environmental Management Site Specific Advisory Boards. Roberson Letter - December 12, 2003 More Documents & Publications Letter: Progress in Implementing a Direct DOE Relationship & Funding for the EMSSABs Letter: Mission, Objectives & Scope of the Site Specific Advisory Board Memorandum: Direction and Guidance for Implementing Direct DOE Relationship

462

Letter: Direction and Guidance for Implementing Direct DOE Relationship &  

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

Letter: Direction and Guidance for Implementing Direct DOE Letter: Direction and Guidance for Implementing Direct DOE Relationship & Funding for EMSSABs Letter: Direction and Guidance for Implementing Direct DOE Relationship & Funding for EMSSABs From: Assistant Secretary, Jessie Hill Roberson (EM-11) To: Mr. Monte Wilson, Chair, INEEL Citizens Advisory Board This letter is in response to a November 21, 2003 letter regarding direction and guidance for implementing direct DOE relationship and funding for Environmental Management Site Specific Advisory Boards. Roberson Letter - December 12, 2003 More Documents & Publications Letter: Progress in Implementing a Direct DOE Relationship & Funding for the EMSSABs Letter: Mission, Objectives & Scope of the Site Specific Advisory Board Memorandum: Direction and Guidance for Implementing Direct DOE Relationship

463

Active and reactive power ripple minimization in direct power control of matrix converter-fed DFIG  

Science Journals Connector (OSTI)

Abstract Despite the advantages of matrix converters (MCs) compared with standard voltage source converters (VSCs), all of the direct power control (DPC) strategies for doubly fed induction generator (DFIG) reported in the literature, only utilize VSCs. In this paper, the influence of MC voltage vectors on active and reactive powers variation is investigated. Compared with VSCs, \\{MCs\\} generate higher number of voltage vectors. Using this inherent advantage of MC, the main contribution of this paper is to reduce large active and reactive power ripples which is one of the main drawbacks of conventional DPC method. Utilizing a wide range of voltage vectors with different amplitudes, a new switching table is derived which using this table, not only large power ripple is compensated but also, a close to unity input power factor for MC can be achieved. In the other word, the presented scheme adds the advantages of MC and DPC together. Moreover, Owing to the operation of MC in direct ac–ac form, the presented scheme effectively eliminates the need for the grid side converter used in conventional DPC, which has a complicated control method is eliminated. Simulation results show the effectiveness of the proposed method and have a reasonable correspondence with theoretical and mathematical analysis.

Arjang Yousefi-Talouki; Edris Pouresmaeil; Bo Nřrregaard Jřrgensen

2014-01-01T23:59:59.000Z

464

A SCR SWITCHED CAPACITOR VOLTAGE REGULATOR FOR 150 kV NEUTRAL BEAM POWER SUPPLY  

E-Print Network [OSTI]

2 ;;o c: REGULATOR BANK SCR TRIGGER CHASSIS BLOCK DIAGRAMLBL-8156 UC-20 A SCR SWITCHED CAPACITOR VOLTAGE REGULATORwill discharge through the SCR and the diodes. All of the

Milnes, K.A.

2011-01-01T23:59:59.000Z

465

Backstepping DC Voltage Control in a Multi-terminal HVDC System Connecting Offshore Wind Farms  

Science Journals Connector (OSTI)

Wind power is projected to play an important ... current and future power systems. To integrate offshore wind farms to the existing onshore grid, voltage source ... in a safe range. To distribute transmitted wind

Xiaodong Zhao; Kang Li; Yusheng Xue

2014-01-01T23:59:59.000Z

466

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

Science Journals Connector (OSTI)

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

Aleksandar Rankovi?; Milan S. Savi?

2010-07-01T23:59:59.000Z

467

Research on Low-Voltage Early Warning System of Coalmine Power Grid  

Science Journals Connector (OSTI)

Research is proposed on coalmine power grid safety-running in case to insure coalmine ... voltage problem now still lying in the coalmine power grid, a method combined fuzzy comprehensive evaluation with gray com...

Tieying Zhao; Na Wang

2012-01-01T23:59:59.000Z

468

Scaling Analysis of On-Chip Power Grid Voltage Variations in Nanometer Scale ULSI  

Science Journals Connector (OSTI)

This paper presents a detailed scaling analysis of the power supply distribution network voltage drop in DSM technologies. The effects of chip temperature, electromigration and interconnect technology scaling (in...

Amir H. Ajami; Kaustav Banerjee…

2005-03-01T23:59:59.000Z

469

Voltage Sag-Related Upsets of Industrial Process Controls in Petroleum and Chemical Industries  

E-Print Network [OSTI]

with PLC controls. The sensitivity of these process controls can stop an essential service motor required for a continuous process such as in a refinery or chemical plant. Typically the controls are sensitive to the common momentary voltage sag caused...

Mansoor, A.; Key, T.; Woinsky, S.

470

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

Broader source: Energy.gov [DOE]

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

471

Insulation co-ordination for continuous operating voltages and temporary overvoltages  

Science Journals Connector (OSTI)

This paper presents an approach to the insulation co-ordination of electric-power installations in ... calculate the necessary required withstand voltages of unit insulations for short-duration (1 min) power-...

Zlatoje Zdravkovi?; Petar Vukelja; Jovan Mrvi?

2006-06-01T23:59:59.000Z

472

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

Science Journals Connector (OSTI)

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

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

473

Algorithms for Combined Inter- and Intra-Task Dynamic Voltage Scaling  

Science Journals Connector (OSTI)

......CDVS well by fully exploiting the benefit of voltage scaling and processor's...No. 2011- 0029805), under the Smart IT Convergence System Research Center...Cognitive Packet Network. Int. Conf. Smart Grids Green Communications and IT Energy-aware......

Hyungjung Seo; Jaewon Seo; Taewhan Kim

2012-11-01T23:59:59.000Z

474

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

Science Journals Connector (OSTI)

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

Qiang Gao; Hongli Wang; Huaxiang Wang

2008-01-01T23:59:59.000Z

475

Fuzzy Control on Voltage/Reactive Power in Electric Power Substation  

Science Journals Connector (OSTI)

A fuzzy method using in voltage and reactive power control in electric substation is proposed based on the improved 17 ... times at the tap positions of transformers in substation are much less than usual. So,...

Xiu-hua Wu; Jun-cheng Wang; Ping Yang…

2009-01-01T23:59:59.000Z

476

A multilevel energy buffer and voltage modulator for grid-interfaced micro-inverters  

E-Print Network [OSTI]

Micro-inverters operating into the single-phase grid from solar photovoltaic (PV) panels or other low-voltage sources must buffer the twice-line-frequency variations between the energy sourced by the PV panel and that ...

Chen, Minjie

477

STATCOM-based voltage and frequency regulator for stand-alone asynchronous generator  

Science Journals Connector (OSTI)

This paper presents a STATCOM-based voltage and frequency regulation for stand-alone asynchronous generator feeding linear and nonlinear loads. The SEIG have inherent poor voltage and frequency regulation. The voltage and frequency depend upon the load current and power factor of the load with fixed excitation capacitor employing unregulated turbines. The changing consumer load requires variable reactive power compensation for excitation requirement. Consumer load contains harmonics and performance of SEIG is largely affected by these load harmonics. A current controlled voltage source inverter working as STATCOM is used for harmonic elimination, load balancing and variable reactive power compensation. A DC chopper with dump load is connected across DC bus capacitor to regulate varying consumer load. The control algorithm has been first co-simulated with processor in the loop (PIL) and then experimentally validated. The transient behaviour of developed prototype system for application and removal of balanced, unbalanced, nonlinear load is investigated.

Dheeraj Kumar Palwalia

2014-01-01T23:59:59.000Z

478

The current-voltage characteristic of a hot-cathode electric arc at low pressures  

Science Journals Connector (OSTI)

It has been shown that in a hot-cathode electric arc operating at low pressures of the working ... drop arises that results in an increase in discharge voltage with current even before the transition of the discharge

C. P. Nikulin

2011-03-01T23:59:59.000Z

479

Nonlinear DSTATCOM controller design for distribution network with distributed generation to enhance voltage stability  

E-Print Network [OSTI]

Nonlinear DSTATCOM controller design for distribution network with distributed generation Accepted 19 June 2013 Keywords: Distributed generation Distribution network DSATACOM Partial feedback connected to a distribution network with distributed generation (DG) to regulate the line voltage

Pota, Himanshu Roy

480

Comparison of resonant current regulators for DFIG during grid voltage distortion  

Science Journals Connector (OSTI)

We investigate two different kinds of resonant current regulators for a doubly fed induction generator (DFIG) under distorted grid voltage conditions: proportional ... part. Based on the mathematical model of DFIG

Yi-peng Song; Heng Nian

2013-12-01T23:59:59.000Z

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


481

In Vivo Voltage-Sensitive Dye Optical Functional Imaging of the Subcortical Brain  

Science Journals Connector (OSTI)

We combined voltage-sensitive dye imaging (VSDi) with gradient-index (GRIN) rod lens to study neural functions in mice vibrissae system. Neural activities evoked in the thalamic...

Tang, Qinggong; Tsytsarev, Vassiliy; Liang, Chia-Pin; Erzurumlu, Reha; Chen, Yu

482

Electrical aging of stator insulation of low voltage rotating machines supplied by inverters  

SciTech Connect (OSTI)

Nowadays, use of inverters for speed variation of low voltage motors becomes more and more usual. The most common technology for this kind of apparatus uses the Pulse Width Modulation (PWM). It is characterized by a square voltage shape with short rise and fall times. In order to insure the quality of turn to ground insulation submitted to these constraints, a study on the aging of Polyethylene terephthalate (Mylar{trademark}) has been undertaken. Influence of rise and fall times, frequency and voltage magnitude has been investigated for time duration up to 1,000 hours. To realize a good voltage application, samples were previously metalized. Two different behaviors according to the rise time and magnitude are observed. For long rise and fall times, changes in the capacity values are obtained although, for smaller rise or fall times, a degradation of the metalized electrode appears. A surface charge generation process is discussed to explain this phenomena.

Bellomo, J.P.; Lebey, T. [Lab. Genie Electrique de Toulouse (France); Oraison, J.M.; Peltier, F. [Leroy-Somer, Angouleme (France)

1996-12-31T23:59:59.000Z

483

Harmonic control of multiple-stator induction machines for voltage regulation  

E-Print Network [OSTI]

Small, one to a few horsepower, three-phase induction machines with three sets of electrically-isolated, magnetically-coupled stator winding circuits are described. A voltage inverter is developed and used to drive one set ...

Holloway, Jack Wade, 1980-

2004-01-01T23:59:59.000Z

484

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

E-Print Network [OSTI]

There are growing industrial demands for low-voltage supply and low-power consumption circuits and systems. This is especially true for very high integration level and very large scale integrated (VLSI) mixed-signal chips and system...

Chen, Mingdeng

2005-02-17T23:59:59.000Z

485

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

E-Print Network [OSTI]

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

Smith, Sterling Lane

2012-06-07T23:59:59.000Z

486

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

Science Journals Connector (OSTI)

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

Akio TAKAOKA; Katsumi URA; Kiyokazu YOSHIDA

1982-01-01T23:59:59.000Z

487

Arc voltage distribution skewness as an indicator of electrode gap during vacuum arc remelting  

DOE Patents [OSTI]

The electrode gap of a VAR is monitored by determining the skewness of a distribution of gap voltage measurements. A decrease in skewness indicates an increase in gap and may be used to control the gap. 4 figs.

Williamson, R.L.; Zanner, F.J.; Grose, S.M.

1998-01-13T23:59:59.000Z

488

State-of-the-Art Fuel Cell Voltage Durability Status: Spring 2013 Composite Data Products  

SciTech Connect (OSTI)

This presentation from the U.S. Department of Energy's National Renewable Energy Laboratory includes composite data products (CDPs) produced in 2013 for state-of-the-art fuel cell voltage durability status.

Kurtz, J.; Sprik, S.; Saur, G.; Peters, M.; Post, M.; Ainscough, C.

2013-05-01T23:59:59.000Z

489

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

Office of Environmental Management (EM)

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

490

Analysis of three-phase rectifiers with constant-voltage loads  

E-Print Network [OSTI]

This work presents a quantitative analysis of the operating characteristics of three-phase diode bridge rectifiers with AC-side reactance and constant-voltage loads. We focus on the case where the AC-side currents vary ...

Caliskan, Vahe

491

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

Science Journals Connector (OSTI)

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

S. P. Bugaev; F. Ya. Zagulov

1973-10-01T23:59:59.000Z

492

On the Simulation of NBTI-Induced Performance Degradation Considering Arbitrary Temperature and Voltage Variations  

Science Journals Connector (OSTI)

With aggressive CMOS technology scaling, Negative Bias Temperature Instability (NBTI) has emerged as one of the major system lifetime reliability threats, which gradually increases PMOS transistor threshold voltage and hence results in increased circuit ...

Ting Wang, Qiang Xu

2014-06-01T23:59:59.000Z

493

Manufacturing challenges of optical current and voltage sensors for utility applications  

SciTech Connect (OSTI)

Measurement of voltages and currents in power transmission and distribution systems are critical to the electric utility industry for both revenue metering and reliability. Nonconventional instrument transformers based on intensity modulation of optical signals have been reported in the literature for more than 20 years. Recently described devices using passive bulk optical sensor elements include the Electro-Optic Voltage Transducer (EOVT) and Magneto-Optic Current Transducer (MOCT). These technologies offer substantial advantages over conventional instrument transformers in accuracy, optical isolation bandwidth, environmental compatibility, weight and size. This paper describes design and manufacturing issues associated with the EOVT and the Optical Metering Unit (OMU) recently introduced by ABB with field installation results presented for prototype units in the 345 kV and 420 kV voltage classes. The OMU incorporates an EOVT and MOCT to monitor the voltage and current on power transmission lines using a single free-standing device.

Yakymyshyn, C.P. [Montana State Univ., Bozeman, MT (United States). Dept. of Electrical and Computer Engineering; Brubaker, M.A. [Los Alamos National Lab., NM (United States); Johnston, P.M. [Johnston (Paul M.), Raleigh, NC (United States); Reinbold, C. [ABB High Voltage Switchgear, Greensburg, PA (United States)

1997-12-01T23:59:59.000Z

494

The constitutive equations for an electrochemically polarizable medium  

E-Print Network [OSTI]

or in time. The general expression for the constitutive equations in these media may then be given by Fi(E(r, t), B(r, t), D(r, t), H(r, t), E(r, t), B(r, t), D(r, t}, H(r, t). . . )K; i=1. . . , , 6 (41) where the dependence on hi~~r order time... equations for a semi-conducting electrochsndcally polarizable medium ~ (49) (50) 26 F2(E(r, t), B(r, t), K(r, t), H(r, t)) = B -u H = 0 (51) where &, u, and & are the permittivity, perma&ility and conductivity of the medium respectively, written...

Benavidez, Alberto

2012-06-07T23:59:59.000Z

495

An Improved Treatment of Cosmological Intergalactic Medium Evolution  

E-Print Network [OSTI]

The modeling of galaxy formation and reionization, two central issues of modern cosmology, relies on the accurate follow-up of the intergalactic medium (IGM). Unfortunately, owing to the complex nature of this medium, the differential equations governing its ionization state and temperature are only approximate. In this paper, we improve these master equations. We derive new expression for the distinct composite inhomogeneous IGM phases, including all relevant ionizing/recombining and cooling/heating mechanisms, taking into account inflows/outflows into/from halos, and using more accurate recombination coefficients. Furthermore, to better compute the source functions in the equations we provide an analytic procedure for calculating the halo mass function in ionized environments, accounting for the bias due to the ionization state of their environment. Such an improved treatment of IGM evolution is part of a complete realistic model of galaxy formation presented elsewhere.

Manrique, Alberto

2015-01-01T23:59:59.000Z

496

Medium and Heavy Duty Vehicle Field Evaluations (Presentation)  

SciTech Connect (OSTI)

This presentation discusses field evaluations of medium- and heavy-duty vehicles performed by NREL. The project provides medium-duty (MD) and heavy-duty (HD) test results, aggregated data, and detailed analysis, including 3rd party unbiased data (data that would not normally be shared by industry in an aggregated and detailed manner). Over 5.6 million miles of advanced technology MD and HD truck data have been collected, documented, and analyzed on over 240 different vehicles since 2002. Data, analysis, and reports are shared within DOE, national laboratory partners, and industry for R&D planning and strategy. The results help guide R&D for new technology development, help define intelligent usage of newly developed technology, and help fleets/users understand all aspects of advanced technology.

Walkowicz, K.

2014-06-01T23:59:59.000Z

497

The Baryon Catastrophe and the multiphase intracluster medium  

E-Print Network [OSTI]

We review the theories and observations which together have led to the concept of the Baryon Catastrophe: observations of the baryon fraction on the scale of clusters of galaxies appear to be at least three times as high as the universal baryon fraction predicted by the theory of primordial nucleosynthesis in a flat, $\\Omega_0 = 1$, universe. We investigate whether this discrepancy could be eliminated by treating the intracluster gas as a multiphase medium, and find that this treatment both lowers the calculated mass of gas in a cluster and increases the inferred gravitational potential. These combined effects can reduce the calculated baryon fraction by between a quarter and a half: the precise amount depends upon the volume fraction distribution of density phases in the gas but is independent of the temperature profile across the cluster. Thus moving to a multiphase intracluster medium cannot resolve the Baryon Catastrophe by itself; other possible causes and explanations are discussed.

K. F. Gunn; P. A. Thomas

1995-10-17T23:59:59.000Z

498

Novel passive lossless turn-on snubber for voltage source inverters  

SciTech Connect (OSTI)

A novel passive lossless turn-on snubber with a soft clamped turn-off snubber circuit for voltage source inverters is proposed. The energy trapped in the snubber is recovered into the dc supply and load without any active devices, associated control circuitry, or resistors. The overshoot voltage on the switches is clamped, and the peak switch current is low, making this snubber suitable for use in high-power insulated gate bipolar transistor (IGBT) inverters.

He, X.; Qian, Z.M. [Zhejiang Univ., Hangzhou (China). Dept. of Electrical Engineering; Finney, S.J.; Williams, B.W. [Heriot-Watt Univ., Edinburgh (United Kingdom). Dept. of Computing and Electrical Engineering

1997-01-01T23:59:59.000Z

499

Hybrid integrated active antennas, voltage-controlled oscillators and switchable & tunable CPW-slotline filters  

E-Print Network [OSTI]

HYBRID INTEGRATED ACTIVE ANTENNAS, VOLTAGE-CONTROLLED OSCILLATORS AND SWITCHABLE & TUNABLE CPW-SLOTLINE FILTERS A Thesis by JULIO ANGEL NAVARRO Submitted to the Office of Graduate Studies of Texas ARM University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE December 1990 Major Subject: Electrical Engineering HYBRID INTEGRATED ACTIVE ANTENNAS, VOLTAGE-CONTROLLED OSCILLATORS AND SWITCHABLE 2 TUNABLE CPW-SLOTLINE FILTERS A Thesis by JULIO ANGEL NAVARRO...

Navarro, Julio A

1990-01-01T23:59:59.000Z

500

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