Sample records for dc direct current

  1. Hardware model of a shipboard zonal electrical distribution system (ZEDS) : alternating current/direct current (AC/DC)

    E-Print Network [OSTI]

    Tidd, Chad N. (Chad Norman)

    2010-01-01T23:59:59.000Z

    A hardware model of a shipboard electrical distribution system based on aspects of the DDG 51 Flight IIA, Arleigh Burke class, 60Hz Alternating Current (AC) and the future direct current (DC), zonal electrical distribution ...

  2. Minimization of DC Reactor and Operation Characteristics of Direct-Power-Controlled Current-Source PWM Rectifier

    E-Print Network [OSTI]

    Fujimoto, Hiroshi

    Minimization of DC Reactor and Operation Characteristics of Direct-Power-Controlled Current control; hence inductance of the DC reactor can be reduced. Feasibility of the strategy is verified characteristics of the direct power control based current-source PWM rectifier with a miniaturized DC reactor

  3. Bi-directional dc-dc Converter

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

    MTBF Dc-dc Fabrication Validation Data Performance Validation BOM and Cost analysis EMIEMC Custom Components Fabrication Components Validation Vehicle System Review Phase-I...

  4. Bi-Directional DC-DC Converter for PHEV Applications

    SciTech Connect (OSTI)

    Abas Goodarzi

    2011-01-31T23:59:59.000Z

    Plug-In Hybrid Electric Vehicles (PHEV) require high power density energy storage system (ESS) for hybrid operation and high energy density ESS for Electric Vehicle (EV) mode range. However, ESS technologies to maximize power density and energy density simultaneously are not commercially feasible. The use of bi-directional DC-DC converter allows use of multiple energy storage, and the flexible DC-link voltages can enhance the system efficiency and reduce component sizing. This will improve fuel consumption, increase the EV mode range, reduce the total weight, reduce battery initial and life cycle cost, and provide flexibility in system design.

  5. Author's Copy: J.B. Bancroft, A. Morrison, G. Lachapelle, Validation of GNSS under 500,000 V Direct Current (DC) transmission lines, Computers and Electronics in Agriculture, Volume 83, April 2012, Pages 58-67, ISSN 0168-1699, 10.1016/j.compag.2012.01.013

    E-Print Network [OSTI]

    Calgary, University of

    masking by the towers. Tests were conducted under a set of three transmission lines, two 500 kV DC lines Current (DC) transmission lines, Computers and Electronics in Agriculture, Volume 83, April 2012, Pages 58 Validation of GNSS under 500,000 Volt Direct Current (DC) Transmission Lines J.B. Bancroft*, A. Morrison

  6. Soft commutated direct current motor [summary of proposed paper

    SciTech Connect (OSTI)

    Hsu, John S.

    1998-10-22T23:59:59.000Z

    A novel soft commutated direct current (DC) motor is introduced. The current of the commutated coil is intentionally drained before the brush disconnects the coil. This prevents the spark generation that normally occurs in conventional DC motors. A similar principle can be applied for DC generators.

  7. Direct current uninterruptible power supply method and system

    DOE Patents [OSTI]

    Sinha, Gautam

    2003-12-02T23:59:59.000Z

    A method and system are described for providing a direct current (DC) uninterruptible power supply with the method including, for example: continuously supplying fuel to a turbine; converting mechanical power from the turbine into alternating current (AC) electrical power; converting the AC electrical power to DC power within a predetermined voltage level range; supplying the DC power to a load; and maintaining a DC load voltage within the predetermined voltage level range by adjusting the amount of fuel supplied to the turbine.

  8. Soft-commutated direct current motor

    DOE Patents [OSTI]

    Hsu, J.S.

    1999-07-27T23:59:59.000Z

    A method and circuit is disclosed for soft-commutation of a direct current (DC) motor. An attenuation circuit is connected through auxiliary brushes A, A[prime], B and B[prime] to the commutator (16) to drain circuit from successive armature coils (15) before the main brushes (27, 28) disconnects from each of the coils (15). This prevents the spark generation that normally occurs in conventional DC motors. The attenuation circuit may also be connected before energization of the coil (15) for a soft turning on operation. 13 figs.

  9. Abstract--Environmentally friendly technologies such as photovoltaics and fuel cells are DC sources. In the current power

    E-Print Network [OSTI]

    Tolbert, Leon M.

    Abstract--Environmentally friendly technologies such as photovoltaics and fuel cells are DC sources in pollution [1]. The most well-known green technologies include photovoltaics and wind turbines. Although fuel, fuel cells and photovoltaics, produce direct current (DC). Currently, power system infrastructures

  10. Optimizing Energy Savings from Direct-DC in U.S. Residential Buildings

    SciTech Connect (OSTI)

    Garbesi, Karina; Vossos, Vagelis; Sanstad, Alan; Burch, Gabriel

    2011-10-13T23:59:59.000Z

    An increasing number of energy efficient appliances operate on direct current (DC) internally, offering the potential to use DC from renewable energy systems directly and avoiding the losses inherent in converting power to alternating current (AC) and back. This paper investigates that potential for net-metered residences with on-site photovoltaics (PV) by modeling the net power draw of the ‘direct-DC house’ with respect to today’s typical configuration, assuming identical DC-internal loads. Power draws were modeled for houses in 14 U.S. cities, using hourly, simulated PV-system output and residential loads. The latter were adjusted to reflect a 33% load reduction, representative of the most efficient DC-internal technology, based on an analysis of 32 electricity end-uses. The model tested the effect of climate, electric vehicle (EV) loads, electricity storage, and load shifting on electricity savings; a sensitivity analysis was conducted to determine how future changes in the efficiencies of power system components might affect savings potential. Based on this work, we estimate that net-metered PV residences could save 5% of their total electricity load for houses without storage and 14% for houses with storage. Based on residential PV penetration projections for year 2035 obtained from the National Energy Modeling System (2.7% for the reference case and 11.2% for the extended policy case), direct-DC could save the nation 10 trillion Btu (without storage) or 40 trillion Btu (with storage). Shifting the cooling load by two hours earlier in the day (pre-cooling) has negligible benefits for energy savings. Direct-DC provides no energy savings benefits for EV charging, to the extent that charging occurs at night. However, if charging occurred during the day, for example with employees charging while at work, the benefits would be large. Direct-DC energy savings are sensitive to power system and appliance conversion efficiencies but are not significantly influenced by climate. While direct-DC for residential applications will most likely arise as a spin-off of developments in the commercial sector—because of lower barriers to market entry and larger energy benefits resulting from the higher coincidence between load and insolation—this paper demonstrates that there are substantial benefits in the residential sector as well. Among residential applications, space cooling derives the largest energy savings from being delivered by a direct-DC system. It is the largest load for the average residence on a national basis and is particularly so in high-load regions. It is also the load with highest solar coincidence.

  11. Direct-current-like Phase Space Manipulation Using Chirped Alternating Current Fields

    SciTech Connect (OSTI)

    P.F. Schmit and N.J. Fisch

    2010-02-01T23:59:59.000Z

    Waves in plasmas can accelerate particles that are resonant with the wave. A dc electric field also accelerates particles, but without a resonance discrimination, which makes the acceleration mechanism profoundly different. Whereas wave-particle acceleration mechanisms have been widely discussed in the literature, this work discusses the direct analogy between wave acceleration and dc field acceleration in a particular parameter regime explored in previous works. Apart from the academic interest of this correspondence, there may be practical advantages in using waves to mimic dc electric fields, for example, in driving plasma current with high efficiency.

  12. E-Print Network 3.0 - average current dc Sample Search Results

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

    tronicsConfrenceAPC 92), Boston,February23-27,pp. 731-7j,. 1;2. A Resonant DC-DC Transformer Summary: State Operation. The steady state voltage and current waveforms when the...

  13. Direct current power transmission systems

    SciTech Connect (OSTI)

    Padiyar, K.R.

    1991-01-01T23:59:59.000Z

    This book represents text on HVDC transmission available. It deals with the various aspects of the state of the art in HVDC transmission technology. This book presents many aspects of interactions of AC/DC systems. Modeling and analysis of DC systems are also discussed in detail.

  14. Application of direct pulsewidth modulation scheme to AC-DC converters: - a way to reduce ripple

    E-Print Network [OSTI]

    Zhang, Yuemin

    1993-01-01T23:59:59.000Z

    Modulation (ISPWM), 4 Direct Pulsewidth Modulation (DPWM). 15 5 Single Phase Half Controlled PWM ac-dc Converter . 6 Single Phase Full controlled PWM ac-dc Converter . 18 18 7 Simulation of SPWM ac-dc Converter. 20 8 Output Voltage Spectra of SPWM ac... 30 Balanced Three Phase Inputs 31 Output Voltage of A Three Phase Full Controlled ac-dc SPWM Converter. 42 32 Output Voltage of A Three Phase Full Controlled ac-dc EPWM Con- verter 33 Output Voltage of A Three Phase Full Controlled ac-dc ISPWM Con...

  15. Summary of multiterminal high-voltage direct current transmission technology

    SciTech Connect (OSTI)

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

    1984-05-01T23:59:59.000Z

    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.

  16. Current Direct Neutrino Mass Experiments

    E-Print Network [OSTI]

    Drexlin, G; Mertens, S; Weinheimer, C

    2013-01-01T23:59:59.000Z

    In this contribution we review the status and perspectives of direct neutrino mass experiments. These experiments investigate the kinematics of $\\beta$-decays of specific isotopes ($^3$H, $^{187}$Re, $^{163}$Ho) to derive model-independent information on the averaged electron (anti-) neutrino mass, which is formed by the incoherent sum of the neutrino mass eigenstates contributing to the electron neutrino. We first review the kinematics of $\\beta$-decay and the determination of the neutrino mass, before giving a brief overview of past neutrino mass measurements (SN1987a-ToF studies, Mainz and Troitsk experiments for $^3$H, cryo-bolometers for $^{187}$Re). We then describe the Karlsruhe Tritium Neutrino (KATRIN) experiment which is currently under construction at Karlsruhe Institute of Technology. The large-scale setup will use the MAC-E-Filter principle pioneered earlier to push the sensitivity down to a value of 200 meV(90% C.L.). KATRIN faces many technological challenges that have to be resolved with regar...

  17. A pulser for medium-frequency modulated direct-current reactive sputter deposition of insulators

    E-Print Network [OSTI]

    Cao, Hui

    for medium-frequency modulated direct-current dc reactive sputter deposition of electrical insulators at the target surface inherent to high- deposition-rate reactive sputtering of electrical insulators. TypicallyA pulser for medium-frequency modulated direct-current reactive sputter deposition of insulators G

  18. Multiphase soft switched DC/DC converter and active control technique for fuel cell ripple current elimination

    DOE Patents [OSTI]

    Lai, Jih-Sheng (Blacksburg, VA); Liu, Changrong (Sunnyvale, CA); Ridenour, Amy (Salem, VA)

    2009-04-14T23:59:59.000Z

    DC/DC converter has a transformer having primary coils connected to an input side and secondary coils connected to an output side. Each primary coil connects a full-bridge circuit comprising two switches on two legs, the primary coil being connected between the switches on each leg, each full-bridge circuit being connected in parallel wherein each leg is disposed parallel to one another, and the secondary coils connected to a rectifying circuit. An outer loop control circuit that reduces ripple in a voltage reference has a first resistor connected in series with a second resistor connected in series with a first capacitor which are connected in parallel with a second capacitor. An inner loop control circuit that reduces ripple in a current reference has a third resistor connected in series with a fourth resistor connected in series with a third capacitor which are connected in parallel with a fourth capacitor.

  19. Impact of quasi-dc currents on three-phase distribution transformer installations

    SciTech Connect (OSTI)

    McConnell, B.W.; Barnes, P.R. (Oak Ridge National Lab., TN (United States)); Tesche, F.M. (Tesche (F.M.), Dallas, TX (United States)); Schafer, D.A. (Mission Research Corp., Albuquerque, NM (United States))

    1992-06-01T23:59:59.000Z

    This report summarizes a series of tests designed to determine the response of quasi-dc currents on three-phase power distribution transformers for electric power systems. In general, if the dc injection is limited to the primary side of a step-down transformer, significant harmonic distortion is noted and an increase in the reactive power demand results. For dc injection on the secondary (load) side of the step-down transformer the harmonic content at the secondary side is quite high and saturation occurs with a relatively low level of dc injection; however, the reactive power demand is significantly lower. These tests produced no apparent damage to the transformers. Transformer damage is dependent on the duration of the dc excitation, the level of the excitation, and on thermal characteristics of the transfer. The transformer response time is found to be much shorter than seen in power transformer tests at lower dc injection levels. This shorter response time suggests that the response time is strongly dependent on the injected current levels, and that higher levels of dc injection for shorter durations could produce very high reactive power demands and harmonic distortion within a few tenths of a second. The added reactive power load could result in the blowing of fuses on the primary side of the transformer for even moderate dc injection levels, and neutral currents are quite large under even low-level dc injection. This smoking neutral'' results in high-level harmonic injection into equipment via the neutral and in possible equipment failure.

  20. Optimizing Energy Savings from Direct-DC in U.S. Residential Buildings

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01T23:59:59.000Z

    a-vis the impact of partial loads on power system componentto test the effect of partial load conditions and possibleto direct-DC savings. Partial load effects reduce estimates

  1. COMPLETELY DC-FREE DIRECT SEQUENCE SPECTRUM SPREADING SCHEME FOR LOW POWER, LOW COST, DIRECT CONVERSION TRANSCEIVER

    E-Print Network [OSTI]

    Lee, Thomas H.

    call the offset code spreading scheme. By employing the scheme, we can implement a direct- conversion- level design. The direct conversion receiver architecture combined with D-BPSK (differential, there are some design problems. In a direct conversion receiver, DC offset due to carrier leakage and 1/f mixer

  2. Phase-Shifted Full Bridge DC-DC Converter with Energy Recovery Clamp and Reduced Circulating Current

    E-Print Network [OSTI]

    of the switch conduction and turn-off losses achieved by an energy recovery secondary clamp circuit an improved PSFB DC-DC converter using only a modified energy recovery clamp circuit attached at the secondaryPhase-Shifted Full Bridge DC-DC Converter with Energy Recovery Clamp and Reduced Circulating

  3. Control of current and voltage oscillations in a short dc discharge making use of external auxiliary electrode

    E-Print Network [OSTI]

    Kaganovich, Igor

    Control of current and voltage oscillations in a short dc discharge making use of external://rsi.aip.org/about/rights_and_permissions #12;REVIEW OF SCIENTIFIC INSTRUMENTS 83, 103502 (2012) Control of current and voltage oscillations October 2012) A dc discharge with a hot cathode is subject to current and voltage plasma oscillations

  4. Hybrid high direct current circuit interrupter

    DOE Patents [OSTI]

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

    1998-08-11T23:59:59.000Z

    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.

  5. Apparatuses and method for converting electromagnetic radiation to direct current

    DOE Patents [OSTI]

    Kotter, Dale K; Novack, Steven D

    2014-09-30T23:59:59.000Z

    An energy conversion device may include a first antenna and a second antenna configured to generate an AC current responsive to incident radiation, at least one stripline, and a rectifier coupled with the at least one stripline along a length of the at least one stripline. An energy conversion device may also include an array of nanoantennas configured to generate an AC current in response to receiving incident radiation. Each nanoantenna of the array includes a pair of resonant elements, and a shared rectifier operably coupled to the pair of resonant elements, the shared rectifier configured to convert the AC current to a DC current. The energy conversion device may further include a bus structure operably coupled with the array of nanoantennas and configured to receive the DC current from the array of nanoantennas and transmit the DC current away from the array of nanoantennas.

  6. Switch contact device for interrupting high current, high voltage, AC and DC circuits

    DOE Patents [OSTI]

    Via, Lester C.; Witherspoon, F. Douglas; Ryan, John M.

    2005-01-04T23:59:59.000Z

    A high voltage switch contact structure capable of interrupting high voltage, high current AC and DC circuits. The contact structure confines the arc created when contacts open to the thin area between two insulating surfaces in intimate contact. This forces the arc into the shape of a thin sheet which loses heat energy far more rapidly than an arc column having a circular cross-section. These high heat losses require a dramatic increase in the voltage required to maintain the arc, thus extinguishing it when the required voltage exceeds the available voltage. The arc extinguishing process with this invention is not dependent on the occurrence of a current zero crossing and, consequently, is capable of rapidly interrupting both AC and DC circuits. The contact structure achieves its high performance without the use of sulfur hexafluoride.

  7. Ferrosilicon smelting in a direct current furnace

    DOE Patents [OSTI]

    Dosaj, V.D.; May, J.B.

    1992-12-29T23:59:59.000Z

    The present invention is a process for smelting ferrosilicon alloy. The process comprises adding a carbon source and tailings comprising oxides of silicon and iron to a substantially closed furnace. Heat is supplied to the furnace by striking a direct current arc between a cathode electrode and an anode functional hearth. In a preferred embodiment of the present invention, the cathode electrode is hollow and feed to the substantially closed furnace is through the hollow electrode. 1 figure.

  8. Mechanism behind self-sustained oscillations in direct current glow discharges and in dusty plasmas

    E-Print Network [OSTI]

    Cho, Sung Nae

    2013-01-01T23:59:59.000Z

    An alternative explanation to the mechanism behind self-sustained oscillations of ions in direct current (DC) glow discharges is provided. Such description is distinguished from the one provided by fluid models, where oscillations are attributed to positive feedback mechanism associated with photoionization of particles and photoemission of electrons from the cathode. Here, oscillations arise as consequence of interaction between an ion and surface charges induced by it at the bounding electrodes. Such mechanism provides an elegant explanation to why self-sustained oscillations occur only in the negative resistance region of the voltage-current characteristic curve in DC glow discharges. It is found that oscillation frequencies increase with ion's surface charge density, but at the rate which is significantly slower than it does with electric field. The presented mechanism also describes the self-sustained oscillations of ions in dusty plasmas, demonstrating that oscillations in dusty plasmas and DC glow disc...

  9. 232 IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 17, NO. 2, MARCH 2002 Current Control Strategy for Brushless DC Motors

    E-Print Network [OSTI]

    Catholic University of Chile (Universidad Católica de Chile)

    synchronous motor (PMSM), which is fed with sinusoidal currents 2) brushless dc motor (BDCM), which is fed, the power-to-weight ratio of PMSM and BDCM is higher than equivalent squirrel cage induction machines

  10. Direct current, closed furnace silicon technology

    SciTech Connect (OSTI)

    Dosaj, V.D. [Dow Corning Corp., Midland, MI (United States); May, J.B. [Dow Corning Corp., Freeland, MI (United States); Arvidson, A.N. [Meadow Materials, Manitoba (Canada)

    1994-05-01T23:59:59.000Z

    The dc closed furnace technology for smelting silicon offers technical operating challenges, as well as, economic opportunities for off-gas recovery, reduced electrode consumption, reduced reductant oxidation losses, reduced energy consumption, and improved silicon recovery. The 10 mva dc closed furnace is located in East Selkirk, Manitoba. Construction of this pilot plant was started in September 1990. Following successful commissioning of the furnace in 1992, a number of smelting tests have been conducted aimed at optimization of the furnace operation and the raw material mix. The operation of a closed furnace is significantly different from an open furnace operation. The major difference being in the mechanical movement of the mix, off-gas recovery, and inability to observe the process. These differences made data collection and analysis critical in making operating decisions. This closed furnace was operated by computer control (state of the art in the smelling industry).

  11. A static voltage-current characteristic for the low current DC arc

    E-Print Network [OSTI]

    Moores, Gregory Lee

    1998-01-01T23:59:59.000Z

    in the literature. Evaluated using the F-statistic, the best model, with a standard error of less than 3V , was a voltage source, opposed to the system voltage, dependent only on arc length. Current only influenced arc lifetime. Varc=l3v+l68v/inch*arc length...

  12. DC to DC power converters and methods of controlling the same

    DOE Patents [OSTI]

    Steigerwald, Robert Louis; Elasser, Ahmed; Sabate, Juan Antonio; Todorovic, Maja Harfman; Agamy, Mohammed

    2012-12-11T23:59:59.000Z

    A power generation system configured to provide direct current (DC) power to a DC link is described. The system includes a first power generation unit configured to output DC power. The system also includes a first DC to DC converter comprising an input section and an output section. The output section of the first DC to DC converter is coupled in series with the first power generation unit. The first DC to DC converter is configured to process a first portion of the DC power output by the first power generation unit and to provide an unprocessed second portion of the DC power output of the first power generation unit to the output section.

  13. Impact of quasi-dc currents on three-phase distribution transformer installations. Power Systems Technology Program

    SciTech Connect (OSTI)

    McConnell, B.W.; Barnes, P.R. [Oak Ridge National Lab., TN (United States); Tesche, F.M. [Tesche (F.M.), Dallas, TX (United States); Schafer, D.A. [Mission Research Corp., Albuquerque, NM (United States)

    1992-06-01T23:59:59.000Z

    This report summarizes a series of tests designed to determine the response of quasi-dc currents on three-phase power distribution transformers for electric power systems. In general, if the dc injection is limited to the primary side of a step-down transformer, significant harmonic distortion is noted and an increase in the reactive power demand results. For dc injection on the secondary (load) side of the step-down transformer the harmonic content at the secondary side is quite high and saturation occurs with a relatively low level of dc injection; however, the reactive power demand is significantly lower. These tests produced no apparent damage to the transformers. Transformer damage is dependent on the duration of the dc excitation, the level of the excitation, and on thermal characteristics of the transfer. The transformer response time is found to be much shorter than seen in power transformer tests at lower dc injection levels. This shorter response time suggests that the response time is strongly dependent on the injected current levels, and that higher levels of dc injection for shorter durations could produce very high reactive power demands and harmonic distortion within a few tenths of a second. The added reactive power load could result in the blowing of fuses on the primary side of the transformer for even moderate dc injection levels, and neutral currents are quite large under even low-level dc injection. This ``smoking neutral`` results in high-level harmonic injection into equipment via the neutral and in possible equipment failure.

  14. Stressing of turbine-generator-exciter shafts by variable-frequency currents superimposed on DC currents in asynchronous HVDC links and following disturbances at converter stations

    SciTech Connect (OSTI)

    Hammons, T.J.; Bremner, J.J. (Univ. of Glasgow (United Kingdom))

    1994-09-01T23:59:59.000Z

    Ripple currents on the DC side of both HVDC synchronous and asynchronous. Links together with cleared HVDC and AC system disturbances can excite in some circumstances onerous torsional vibrations in large steam generator shafts. The problem has assumed importance in recent months on account of the HVDC Link between Scotland and Northern Ireland going ahead, on account of the proposed Eire/Wales Link, and because AC/DC/AC couplers are to be installed extensively to interconnect the East and West European Grid Systems. This paper discusses and analyses excitation of shaft torsional vibrations in steam turbine-generator-exciter shafts in close proximity to HVDC converter stations by (1) variable-frequency ripple currents superimposed on the DC currents in asynchronous Links, and (2) disturbances at bi-polar converter stations. The time response and tables show that for the systems studied variable-frequency ripple currents superimposed on the DC current in asynchronous Links can excite shaft torsional vibrations, the very small noncharacteristic currents could result in onerous shaft torques which might damage the machine, and that DC line faults at converter stations in close proximity of steam turbine-generator units can excite onerous turbine-generator shaft torsional response. Detailed simulation of the HVDC converter and generator is necessary for precise assessments of shaft torsional response following HVDC converter station faults. 500MW, 660MW, 1000MW and 1300MW machines are considered in the analyses that are made.

  15. Low energy electron-enhanced etching of Si(100) in hydrogen/helium direct-current plasma

    E-Print Network [OSTI]

    Dove, Patricia M.

    Low energy electron-enhanced etching of Si(100) in hydrogen/helium direct-current plasma H. P of a dc plasma reactor, and thus receives a large flux of low-energy electrons and hydrogen molecules-0269 Received 7 September 1994; accepted for publication 6 March 1995 Low energy electron-enhanced etching of Si

  16. EIS-0107: Mead-Phoenix +500-kV Direct Current Transmission Line

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy’s Western Area Power Administration (WAPA) prepared this statement to analyze the potential environmental and socioeconomic impacts arising from WAPA and regional project sponsors’ proposal to construct a 500 kilovolt (kV) alternating current (AC) transmission line with the capability to be upgraded later to 500kV direct current (DC), connecting the Westwing Substation, located north of Phoenix, Arizona, with a new McCullough II Substation, located approximately 14 miles west of Boulder City, Nevada. This statement modifies a previously prepared federal statement from which the participants' election to proceed had not occurred at the time this statement was prepared.

  17. In Proc of Direct Methanol Fuel Cell Symposium, 199th Electrochem.l Soc. Mtg, Washington DC, 3/01.

    E-Print Network [OSTI]

    Wang, Chao-Yang

    In Proc of Direct Methanol Fuel Cell Symposium, 199th Electrochem.l Soc. Mtg, Washington DC, 3/01. MATHEMATICAL MODELING OF LIQUID-FEED DIRECT METHANOL FUEL CELLS Z. H. Wang and C. Y. Wang Electrochemical methanol fuel cells (DMFC). Diffusion and convection of both gas and liquid phases are considered

  18. Phenomena of oscillations in atmospheric pressure direct current glow discharges

    SciTech Connect (OSTI)

    Liu, Fu-cheng [College of Physics Science and Technology, Hebei University, Baoding 071002 (China)] [College of Physics Science and Technology, Hebei University, Baoding 071002 (China); Yan, Wen; Wang, De-zhen [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)] [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

    2013-12-15T23:59:59.000Z

    Self-sustained oscillations in a dc glow discharge with a semiconductor layer at atmospheric pressure were investigated by means of a one-dimensional fluid model. It is found that the dc glow discharge initially becomes unstable in the subnormal glow region and gives rise to oscillations of plasma parameters. A variety of oscillations with one or more frequencies have been observed under different conditions. The discharge oscillates between the glow discharge mode and the Townsend discharge mode in the oscillations with large amplitude while operates in the subnormal glow discharge mode all the while in the oscillations with small amplitude. Fourier Transform spectra of oscillations reveal the transition mechanism between different oscillations. The effects of semiconductor conductivity on the oscillation frequency of the dominant mode, gas voltage, as well as the discharge current have also been analyzed.

  19. anodal direct current: Topics by E-print Network

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

    a model is (more) Bridges, Nathaniel Reese 2011-01-01 15 Design of Reactances and Transformers Which Carry Direct Current Engineering Websites Summary: Design of Reactances and...

  20. Direct-Current Resistivity Survey At Blue Mountain Area (Fairbank...

    Open Energy Info (EERE)

    Blue Mountain Area (Fairbank Engineering Ltd, 2005) Exploration Activity Details Location Blue Mountain Area Exploration Technique Direct-Current Resistivity Survey Activity Date...

  1. Direct-Current Resistivity At Cove Fort Area - Liquid (Warpinski...

    Open Energy Info (EERE)

    Warpinski, Et Al., 2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Direct-Current Resistivity At Cove Fort Area - Liquid (Warpinski, Et...

  2. Direct-Current Resistivity Survey At Mauna Loa Northeast Rift...

    Open Energy Info (EERE)

    Mauna Loa Northeast Rift Area (Thomas, 1986) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Direct-Current Resistivity Survey At Mauna Loa...

  3. Auxiliary resonant DC tank converter

    DOE Patents [OSTI]

    Peng, Fang Z. (Knoxville, TN)

    2000-01-01T23:59:59.000Z

    An auxiliary resonant dc tank (ARDCT) converter is provided for achieving soft-switching in a power converter. An ARDCT circuit is coupled directly across a dc bus to the inverter to generate a resonant dc bus voltage, including upper and lower resonant capacitors connected in series as a resonant leg, first and second dc tank capacitors connected in series as a tank leg, and an auxiliary resonant circuit comprising a series combination of a resonant inductor and a pair of auxiliary switching devices. The ARDCT circuit further includes first clamping means for holding the resonant dc bus voltage to the dc tank voltage of the tank leg, and second clamping means for clamping the resonant dc bus voltage to zero during a resonant period. The ARDCT circuit resonantly brings the dc bus voltage to zero in order to provide a zero-voltage switching opportunity for the inverter, then quickly rebounds the dc bus voltage back to the dc tank voltage after the inverter changes state. The auxiliary switching devices are turned on and off under zero-current conditions. The ARDCT circuit only absorbs ripples of the inverter dc bus current, thus having less current stress. In addition, since the ARDCT circuit is coupled in parallel with the dc power supply and the inverter for merely assisting soft-switching of the inverter without participating in real dc power transmission and power conversion, malfunction and failure of the tank circuit will not affect the functional operation of the inverter; thus a highly reliable converter system is expected.

  4. Mechanism behind self-sustained oscillations in direct current glow discharges and dusty plasmas

    SciTech Connect (OSTI)

    Cho, Sung Nae [Devices R and D Center, Samsung Advanced Institute of Technology, Samsung Electronics Co., Ltd., Mt. 14-1 Nongseo-dong, Giheung-gu, Yongin-si, Gyeonggi-do 446-712 (Korea, Republic of)

    2013-04-15T23:59:59.000Z

    An alternative explanation to the mechanism behind self-sustained oscillations of ions in direct current (DC) glow discharges is provided. Such description is distinguished from the one provided by the fluid models, where oscillations are attributed to the positive feedback mechanism associated with photoionization of particles and photoemission of electrons from the cathode. Here, oscillations arise as consequence of interaction between an ion and the surface charges induced by it at the bounding electrodes. Such mechanism provides an elegant explanation to why self-sustained oscillations occur only in the negative resistance region of the voltage-current characteristic curve in the DC glow discharges. Furthermore, this alternative description provides an elegant explanation to the formation of plasma fireballs in the laboratory plasma. It has been found that oscillation frequencies increase with ion's surface charge density, but at the rate which is significantly slower than it does with the electric field. The presented mechanism also describes self-sustained oscillations of ions in dusty plasmas, which demonstrates that self-sustained oscillations in dusty plasmas and DC glow discharges involve common physical processes.

  5. Direct-current effects on magnetization reversal properties of submicron-size permalloy patterns for radio-frequency devices.

    SciTech Connect (OSTI)

    Zhang, H.; Hoffmann, A.; Divan, R.; Wang, P.; Clemson Univ.

    2009-01-01T23:59:59.000Z

    Ferromagnetic resonance (FMR) spectroscopy is used to measure direct-current (dc) effects on the magnetization reversal properties of submicron-sized lateral patterned magnetic material. The observed FMR frequency-field relationship shows that for both 240 and 550 nm wide Permalloy (Py) nanowires the coercivity is reduced by {approx}33% when a 50 mA dc passes through the transmission line where the nanowires are incorporated. The temperature dependence of the coercivity has a {radical}T relationship which suggests the coherent rotation mode tendency in such 100 nm thick Py nanowires.

  6. A Superconducting transformer system for high current cable testing

    E-Print Network [OSTI]

    Godeke, A.

    2010-01-01T23:59:59.000Z

    A Superconducting Transformer System for High Current Cablea Direct-Current (DC) superconducting transformer system forhigh current test of superconducting cables. The transformer

  7. Over-Current Protection Scheme for SiC Power MOSFET DC Circuit Breaker

    E-Print Network [OSTI]

    Zhang, Yuan; Liang, Yung C.

    2015-01-01T23:59:59.000Z

    V. Radun, “SiC based solid state power controller,” in 23tha solid-state circuit breaker based on SiC power MOSFET withSolid-state DC circuit breakers made of the modern wide bandgap power

  8. Optimizing Energy Savings from Direct-DC in U.S. Residential Buildings

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01T23:59:59.000Z

    Appliance type Standard technology DC-internal best technology Lighting Incandescent, fluorescent, LED Incandescent Electronic Heating Heater Electric resistance Cooling Motor (& compressor,

  9. Power links with Ireland -- Excitation of turbine-generator shaft torsional vibrations by variable frequency currents superimposed on DC currents in asynchronous HVDC links

    SciTech Connect (OSTI)

    Hammons, T.J.; Tay, B.W.; Kok, K.L. [Glasgow Univ. (United Kingdom)] [Glasgow Univ. (United Kingdom)

    1995-08-01T23:59:59.000Z

    The paper describes an in-depth analysis of excitation of shaft torsional vibrations in steam-turbine-generator-exciter shafts in close proximity to HVDC converter stations by variable-frequency ripple currents superimposed on the DC currents in asynchronous Links. It extends earlier work to include an in depth analysis of system scaling factors for harmonic currents impressed on generators in Northern Ireland by an inverter and to investigate the phenomena for possible torsional vibrations in the generators by the Link. Frequencies at which shaft torsional vibrations would be excited by modulation product harmonics in 50Hz/50Hz asynchronous Links as a function of deviation in system frequency is reviewed. Relative noncharacteristic current levels for 50Hz/50Hz connectors are illustrated assuming ripple currents at the inverter which gives realistic harmonic voltages in a twelve-pulse bridge. The paper then shows that torques in machines in multi-machine networks may be estimated by proportioning HVDC link harmonic disturbance current appropriately to each machine at risk. It is concluded that variable-frequency ripple currents superimposed on the DC current in asynchronous links can excite sympathetic torsional vibrations in turbine-generator-exciter shafts.

  10. Optimizing Energy Savings from Direct-DC in U.S. Residential Buildings

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01T23:59:59.000Z

    wind/fuel cell hybrid energy systems. Energy and Buildings,National Energy Modeling System PHEV plug-in hybrid electrica hybrid DC and AC power system that included energy storage

  11. Analysis of variable-frequency currents superimposed on DC currents in asynchronous HVDC Links in stressing turbine-generator-exciter shafts

    SciTech Connect (OSTI)

    Hammons, T.J.; Bremner, J.J. [Univ. of Glasgow (United Kingdom)] [Univ. of Glasgow (United Kingdom)

    1995-03-01T23:59:59.000Z

    Ripple currents on the DC side of both HVDC asynchronous and synchronous Links can excite in some circumstances onerous torsional vibrations in large steam generator shafts. The problem has assumed importance in recent months on account of the HVDC Link between Scotland and Northern Ireland going ahead, on account of the proposed Eire/Wales Link, because AC/DC/AC couplers are to be installed to interconnect the East and West European Grid Systems, and because resonances have been observed on machines in close proximity to AC/DCIAC couplers and HVDC Links. This paper discusses and analyses excitation of shaft torsional vibrations in steam turbine-generator-exciter shafts in close proximity to HVDC converter stations by variable-frequency ripple currents superimposed on DC currents in asynchronous Links. It presents technical knowledge not arranged for convenient reference heretofore in studying possible excitation of turbine-generator-v/ exciter shaft torsional vibrations by non-characteristic HVDC converter harmonic currents if a machine should be considered to be at risk. Shaft torques in multi-machine networks are evaluated by proportioning HVDC Link disturbance currents to each machine at risk using system network data, generator data and fault analysis data considering frequency dependence of the system parameters. This scaling factor is calculated for different scenarios of system operation and load. Equivalent circuits for the synchronous generator are employed appropriately to correlate HVDC Link disturbance current impressed on the generator stator with s state torque excitation from which magnitude of turbine-generator-exciter shaft torque is deduced.

  12. DC attenuation meter

    DOE Patents [OSTI]

    Hargrove, Douglas L.

    2004-09-14T23:59:59.000Z

    A portable, hand-held meter used to measure direct current (DC) attenuation in low impedance electrical signal cables and signal attenuators. A DC voltage is applied to the signal input of the cable and feedback to the control circuit through the signal cable and attenuators. The control circuit adjusts the applied voltage to the cable until the feedback voltage equals the reference voltage. The "units" of applied voltage required at the cable input is the system attenuation value of the cable and attenuators, which makes this meter unique. The meter may be used to calibrate data signal cables, attenuators, and cable-attenuator assemblies.

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

    SciTech Connect (OSTI)

    Not Available

    1988-04-01T23:59:59.000Z

    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.

  14. Active electron energy distribution function control in direct current discharge using an auxiliary electrode

    SciTech Connect (OSTI)

    Schweigert, I. V. [Institute of Theoretical and Applied Mechanics, Novosibirsk 630090 (Russian Federation) [Institute of Theoretical and Applied Mechanics, Novosibirsk 630090 (Russian Federation); George Washington University, Washington, DC 20052 (United States); Kaganovich, I. D. [Princeton Plasma Physics Laboratory, Princeton, NJ 08543 (United States)] [Princeton Plasma Physics Laboratory, Princeton, NJ 08543 (United States); Demidov, V. I. [West Virginia University, Morgantown, WV 26506 (United States) [West Virginia University, Morgantown, WV 26506 (United States); St. Petersburg State University, St. Petersburg (Russian Federation)

    2013-10-15T23:59:59.000Z

    The electron energy distribution functions are studied in the low voltage dc discharge with a constriction, which is a diaphragm with an opening. The dc discharge glows in helium and is sustained by the electron current emitted from a heated cathode. We performed kinetic simulations of dc discharge characteristics and electron energy distribution functions for different gas pressures (0.8 Torr-4 Torr) and discharge current of 0.1 A. The results of these simulations indicate the ability to control the shape of the electron energy distribution functions by variation of the diaphragm opening radius.

  15. Predicting Air Quality: Current Status and Future Directions

    E-Print Network [OSTI]

    Sandu, Adrian

    Predicting Air Quality: Current Status and Future Directions Gregory R. Carmichael ,a Adrian Sandu, OR 97207, USA Abstract Air quality prediction plays an important role in the management of our envi can predict pollution in an urban air shed with spatial resolution less than a kilometer, and cover

  16. Transformer coupling for transmitting direct current through a barrier

    DOE Patents [OSTI]

    Brown, R.L.; Guilford, R.P.; Stichman, J.H.

    1987-06-29T23:59:59.000Z

    The transmission system for transmitting direct current from an energy source on one side of an electrical and mechanical barrier to a load on the other side of the barrier utilizes a transformer comprising a primary core on one side of the transformer and a secondary core on the other side of the transformer. The cores are magnetically coupled selectively by moving a magnetic ferrite coupler in and out of alignment with the poles of the cores. The direct current from the energy source is converted to a time varying current by an oscillating circuit, which oscillating circuit is optically coupled to a secondary winding on the secondary core to interrupt oscillations upon the voltage in the secondary winding exceeding a preselected level. 4 figs.

  17. Transformer coupling for transmitting direct current through a barrier

    DOE Patents [OSTI]

    Brown, Ralph L. (Albuquerque, NM); Guilford, Richard P. (Albuquerque, NM); Stichman, John H. (Albuquerque, NM)

    1988-01-01T23:59:59.000Z

    The transmission system for transmitting direct current from an energy source on one side of an electrical and mechanical barrier to a load on the other side of the barrier utilizes a transformer comprising a primary core on one side of the transformer and a secondary core on the other side of the transformer. The cores are magnetically coupled selectively by moving a magnetic ferrite coupler in and out of alignment with the poles of the cores. The direct current from the energy source is converted to a time varying current by an oscillating circuit, which oscillating circuit is optically coupled to a secondary winding on the secondary core to interrupt oscillations upon the voltage in the secondary winding exceeding a preselected level.

  18. POSITION ESTIMATOR AND SIMPLIFIED CURRENT CONTROL STRATEGY FOR BRUSHLESS-DC MOTORS, USING DSP TECHNOLOGY

    E-Print Network [OSTI]

    Catholic University of Chile (Universidad Católica de Chile)

    motor (PMSM), with sinusoidal back emf. This machine has been tested with quasi-square current waveforms

  19. Damping of a parallel ac-dc power system using PID power system stabilizers and rectifier current regulators

    SciTech Connect (OSTI)

    Hsu, Y.Y.; Wang, L. (Dept. of Electrical Engineering, National Taiwan Univ., Taipei (TW))

    1988-09-01T23:59:59.000Z

    A novel approach is presented to improve the dynamic stability of a parallel AC-DC power system. The developed scheme employs a proportional-integral-derivative (PID) power system stabilizer (PSS) and a PID rectifier current regulator (RCR) to enhance the damping for the electromagnetical mode of the system. The parameters of the proposed PID controllers are determined using a unified approach based on modal control theory. Eigenvalue analyses are performed for the system under various operating conditions in order to compare the damping effects provided by the two different control schemes. To demonstrate the effectiveness of the proposed damping schemes under disturbance conditions simulated dynamic response tests based on a nonlinear system model are also performed.

  20. DC BUFFERING AND FLOATING CURRENT FOR A HIGH VOLTAGE IMB APPLICATION

    SciTech Connect (OSTI)

    J.L. Morrison

    2014-08-01T23:59:59.000Z

    An interface technique for the latest generation of the Impedance Measurement Box (IMB) has been conceived to enable measurement of impedance spectra for battery modules up to 300V. A 300V capable or higher IMB is an enabling technology for in-situ diagnostics within electric vehicle charging stations or battery back-ups within power distribution sub-stations. It is possible that the existing IMB can be adapted via a 300V interface module to a test battery with voltage significantly greater than 50V. Recently a new concept was conceived for the calibration, algorithm and electronics of the IMB. That algorithm and calibration for that concept have been physically validated. The principal feature of the new electronics is the floating current source excitation of the battery under test. The single ended current excitation of the battery under test, used in the 50V IMB, requires that the negative terminal of the test battery must be the analog ground for the IMB. The new floating current technique allows the test battery to be fully high impedance isolated for a measurement. That isolation will improve IMB noise immunity and enable interrogation of cells internal to a battery module. All these techniques still use the same rapid concept for impedance measurement with the IMB. The purpose of this disclosure is to provide an overview of the analytical validation for three concepts to interface the floating current excitation to a high voltage battery. Recursive simulation models were used in different test scenarios to validate the various new concepts. The analysis will show that it is possible to interface the floating signal current to obtain an impedance measurement on a high voltage test battery. Additionally, the analysis will investigate stress seen by electronics while testing a 300V battery.

  1. Dependence of the magnitude and direction of the persistent current on the magnetic flux in superconducting rings

    SciTech Connect (OSTI)

    Gurtovoi, V. L.; Dubonos, S. V.; Nikulov, A. V., E-mail: nikulov@ipmt-hpm.ac.ru; Osipov, N. N.; Tulin, V. A. [Russian Academy of Sciences, Institute of Microelectronic Technology and High-Purity Materials (Russian Federation)

    2007-12-15T23:59:59.000Z

    The obtained periodic magnetic-field dependences I{sub c+}({phi}/{phi}{sub 0}) and I{sub c-}({phi}/{phi}{sub 0}) of the critical current measured in opposite directions on asymmetric superconducting aluminum rings has made it possible to explain previously observed quantum oscillations of dc voltage as a result of alternating current rectification. It was found that a higher rectification efficiency of both single rings and ring systems is caused by hysteresis of the current-voltage characteristics. The asymmetry of current-voltage characteristics providing the rectification effect is due to the relative shifts of the magnetic dependences I{sub c-}({phi}/{phi}{sub 0}) = I{sub c+}({phi}/{phi}{sub 0} + {delta}{phi}) of the critical current measured in opposite directions. This shift means that the position of I{sub c+}({phi}/{phi}{sub 0}) and I{sub c-}({phi}/{phi}{sub 0}) minima does not correspond to n + 0.5 magnetic flux {phi} quanta, which is in direct contradiction to measured Little-Parks resistance oscillations. Despite this contradiction, the amplitude I{sub c,an}({phi}/{phi}{sub 0}) = I{sub c+}({phi}/{phi}{sub 0}) - I{sub c-}({phi}/{phi}{sub 0}) of critical current anisotropy oscillations and its variations with temperature correspond to the expected amplitude of persistent current oscillations and its variations with temperature.

  2. High-voltage direct current handbook: First edition

    SciTech Connect (OSTI)

    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

    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.

  3. Evaluation of a Current Source Active Power Filter to Reduce the DC Bus Capacitor in a Hybrid Electric Vehicle Traction Drive

    E-Print Network [OSTI]

    Tolbert, Leon M.

    system, additional heat, audible noise, mechanical stress, and vibration [1]. DC bus harmonic current- powered three-phase inverter is used to drive the traction motor. Due to the switching behavior combustion engine, electric motor, and energy storage device (for example, batteries and ultracapacitors

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

    E-Print Network [OSTI]

    Essakiappan, Somasundaram

    2011-08-08T23:59:59.000Z

    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...

  5. Method and apparatus for monitoring armature position in direct-current solenoids

    DOE Patents [OSTI]

    Moyers, John C. (Oak Ridge, TN); Haynes, Howard D. (Knoxville, TN)

    1996-12-10T23:59:59.000Z

    A method for determining the position of an armature of a dc-powered solenoid. Electrical circuitry is provided to introduce a small alternating current flow through the coil. As a result, the impedance and resistance of the solenoid coil can be measured to provide information indicative of the armature's position.

  6. Measured Savings of DC to AC Drive Retrofit in Plastic Extrusion

    E-Print Network [OSTI]

    Sfeir, R. A.

    2008-01-01T23:59:59.000Z

    This paper presents the potential electrical energy efficiency improvements for utilizing alternating current (AC) motors controlled by variable frequency drives (VFD) in place of direct current (DC) motors to drive plastic extrusion machines. A...

  7. Catalog of DC Appliances and Power Systems

    SciTech Connect (OSTI)

    Garbesi, Karina; Vossos, Vagelis; Shen, Hongxia

    2010-10-13T23:59:59.000Z

    This document catalogs the characteristics of current and potential future DC products and power systems.

  8. A High Frequency Isolated Current-fed Bidirectional DC/AC Converter For Grid-Tied Energy Storage System

    E-Print Network [OSTI]

    King Jet, TSENG

    2013-01-01T23:59:59.000Z

    tied energy storage systems (ESS) will be voltage to a high-DC/AC converter to interface ESS based on low voltage cellscharging and discharging of the ESS and the control strategy

  9. A Generalized Class of Stationary Frame-Current Controllers for Grid-Connected AC–DC Converters

    E-Print Network [OSTI]

    Hwang, J. George

    Within power systems, high-power pulsewidth-modulated ac-dc converters are used in flexible ac transmission systems controllers and for interfacing renewable energy sources to the grid. These converters traditionally ...

  10. Electrochemical synthesis of nanosized hydroxyapatite by pulsed direct current method

    SciTech Connect (OSTI)

    Nur, Adrian; Rahmawati, Alifah; Ilmi, Noor Izzati; Affandi, Samsudin; Widjaja, Arief [Departement of Chemical Engineering, Faculty of Industrial Technology, Sepuluh Nopember Institute of Technology, Kampus ITS Sukolilo, Surabaya 60111 (Indonesia)

    2014-02-24T23:59:59.000Z

    Synthesis of nanosized of hydroxyapatite (HA) by electrochemical pulsed direct current (PDC) method has been studied. The aim of this work is to study the influence of various PDC parameters (pH initial, electrode distance, duty cycle, frequency, and amplitude) on particle surface area of HA powders. The electrochemical synthesis was prepared in solution Ca{sup 2+}/EDTA{sup 4?}/PO{sub 4}{sup 3+} at concentration 0.25/0.25/0.15 M for 24 h. The electrochemical cell was consisted of two carbon rectangular electrodes connected to a function generator to produce PDC. There were two treatments for particles after electrosynthesized, namely without aging and aged for 2 days at 40 °C. For both cases, the particles were filtered and washed by demineralized water to eliminate the impurities and unreacted reactants. Then, the particles were dried at 100 °C for 2 days. The dried particles were characterized by X-ray diffraction, surface area analyzer, scanning electron microscopy (SEM), Fourier transform infrared spectra and thermogravimetric and differential thermal analysis. HA particles can be produced when the initial pH > 6. The aging process has significant effect on the produced HA particles. SEM images of HA particles showed that the powders consisted of agglomerates composed of fine crystallites and have morphology plate-like and sphere. The surface area of HA particles is in the range of 25 – 91 m{sup 2}/g. The largest particle surface area of HA was produced at 4 cm electrode distance, 80% cycle duty, frequency 0.1 Hz, amplitude 9 V and with aging process.

  11. IEEE Applied Power Elecb"onics Confererice (APEC '93) Record, pp. 58-64, San Diego, March 1993. Current-Fed Multi-Resonant DC-DC Converter

    E-Print Network [OSTI]

    .: +(972) 57461-561; FAX: +(972) 57281-340; Email: SBY@BGUEE.BI1NET Department of ElecUical and Computer at the output, a high voltage gain and zero voltage switching over a iarge range of output voitage against short circuit at the output while maintaining Zero Voltage Switching (ZVS) or Zero Current

  12. Ver.2003.01.27 Development of Low-Voltage and Large-Current DC Power Supply

    E-Print Network [OSTI]

    Fujimoto, Hiroshi

    -4000A 1kHz 1kHz 940-2188 1603-1 Nagaoka University of Technology 1603-1 Kamitomioka, Nagaoka : 1 4 13V-5000A Fig. 4. Cross section diagram of high-frequency step down transformer of 13V-5000A DC

  13. Direct Biological Conversion of Electrical Current into Methane by

    E-Print Network [OSTI]

    electrical energy and substrate heat of combustion energy (82%) (3). One disadvantage of electrically-chamber MEC, methane was produced at anoverallenergyefficiencyof80%(electricalenergyandsubstrate heat of combustion). These results show that electrometha- nogenesis can be used to convert electrical current

  14. Lightning strikes to tall objects: Currents inferred from far electromagnetic fields versus directly measured currents

    E-Print Network [OSTI]

    Florida, University of

    -field-to-current conversion factor for lightning strikes to flat ground based on the transmission line model and (b currents on tall towers are used for testing the validity of field-to-current conversion equations [e on current measurement location (e.g., near the top or bottom of the tower) and on whether initial or largest

  15. Theoretical investigation of the effect of hydrogen addition on the formation and properties of soliton in direct current argon plasma

    SciTech Connect (OSTI)

    Saikia, P., E-mail: partha.008@gmail.com; Goswami, K. S.; Saikia, B. K. [Centre of Plasma Physics, Institute for Plasma Research, Nazirakhat, Sonapur, Kamrup, Assam-782 402 (India)] [Centre of Plasma Physics, Institute for Plasma Research, Nazirakhat, Sonapur, Kamrup, Assam-782 402 (India)

    2014-03-15T23:59:59.000Z

    In this study the effect of hydrogen addition on the formation and properties of soliton in direct-current (DC) argon plasma is theoretically investigated. By coupling fluid equations with Poisons equation for such multi-component plasma, the Mach number and amplitude of the soliton are determined following pseudo potential method. Addition of hydrogen in argon discharge leads to the decrease of electron, Ar{sup +} ion density while a reverse trend was observed for ArH{sup +} and hydrogen like ions. It was found that presence of hydrogen like ions in argon plasma affects the formation of soliton with its amplitude significantly decreases as concentration of hydrogen increases. On the other hand, increase in ion to electron temperature ratios of the lighter ions in the discharge also has a significant influence on the amplitude and formation of soliton. The inverse relation between solitons width and amplitude is found to be consistent for the entire range of study.

  16. Direct current sputtering of boron from boron/boron mixtures

    DOE Patents [OSTI]

    Timberlake, J.R.; Manos, D.; Nartowitz, E.

    1994-12-13T23:59:59.000Z

    A method for coating a substrate with boron by sputtering includes lowering the electrical resistance of a boron-containing rod to allow electrical conduction in the rod; placing the boron-containing rod inside a vacuum chamber containing substrate material to be coated; applying an electrical potential between the boron target material and the vacuum chamber; countering a current avalanche that commences when the conduction heating rate exceeds the cooling rate, and until a steady equilibrium heating current is reached; and, coating the substrate material with boron by sputtering from the boron-containing rod. 2 figures.

  17. A graphical method for determining electrical conductivity of ionic solutions by direct current

    E-Print Network [OSTI]

    Simpson, Harold Navayne

    2012-06-07T23:59:59.000Z

    Ce AND D. C, HEASURENENTS IH PHASE I FOR VARIOUS CONCENTRATIONS OF Pb(N03)2 AT 30 C Normality R K AC K DC k (ohms) (ob%1 ow ) (os% N& ) (0% ) 1, 0000 0. 5000 0. 2000 0. 1000 23t 5 31, 8 52. 4 86. 7 0. 0752 0. 0541 0. 0305 0. 0167 0. 0757 0... ~ ~ ~ ~ t ~ ~ t ~ ~ ~ ~ ~ ~ 32 7. R ~ vs Current Data for Varions Oonoentratione of Ph(803)2 sell Solntione at 30 C Phase I ~ ~ ~ ~ ~ ~ t ~ ~ ~ t ~ ~ ~ ~ ~ ~ 33 8. Graphical Data for Varioas Conoentrations of Pb(803)2 at 0 30 c PhaN I...

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

    E-Print Network [OSTI]

    Dimarogonas, Dimos

    }@kth.se.) Abstract: High-voltage direct current (HVDC) is a commonly used technology for long-distance power for multi-terminal HVDC (MTDC) systems is proposed. Under certain conditions on the controller gains factor behind long-distance power transmission. High-voltage direct current (HVDC) is a commonly used

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

    SciTech Connect (OSTI)

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

    2014-12-11T23:59:59.000Z

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

  20. Electrochimica Acta 52 (2007) 43174324 Porous current collectors for passive direct methanol fuel cells

    E-Print Network [OSTI]

    Zhao, Tianshou

    2007-01-01T23:59:59.000Z

    Electrochimica Acta 52 (2007) 4317­4324 Porous current collectors for passive direct methanol fuel methanol fuel cell (DMFC) with its cathode current collector made of porous metal foam was investigated that the passive DMFC having the porous current collector yielded much higher and much more stable performance than

  1. Stochastic ratcheting of two dimensional colloids : Directed current and dynamical transitions

    E-Print Network [OSTI]

    Dipanjan Chakraborty; Debasish Chaudhuri

    2014-07-09T23:59:59.000Z

    We present results of molecular dynamics simulations for two-dimensional repulsively interacting colloids driven by an one dimensional asymmetric and commensurate ratchet potential, switching on and off stochastically. The resultant time- and space-averaged directed current exhibits resonance with change in ratcheting frequency. The resonance frequency itself varies non-monotonically with density. We use scaling arguments to derive analytic expression for the directed current which reproduces these features. Our simulations reveal re-entrant dynamical transitions between solid and modulated liquid phases as a function of ratcheting frequency, associated with the variation of directed current.

  2. Bi-directional dc-dc Converter

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

    Gate drive over -voltage protection T 1 SiC VJFET T 2 D 1 D 2 R g Built-in UV lockout 2008 DOE Merit Review Guidelines Preliminary, Experimental Gate-drive Results 11 V ds...

  3. Bi-directional dc-dc Converter

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

    Custom Components Fabrication Components Validation Vehicle System Review with customer Delay of FY09 schedule Design Functional Validation, EMIEMC Production Planning PPAP, APQP...

  4. The effect of a direct current field on the microparticle charge in the plasma afterglow

    SciTech Connect (OSTI)

    Wörner, L. [Max Planck Institute for extraterrestrial Physics, P.O. Box 1312, Giessenbachstr., 85741 Garching (Germany) [Max Planck Institute for extraterrestrial Physics, P.O. Box 1312, Giessenbachstr., 85741 Garching (Germany); Groupe de Recherches sur l'Energétique des Milieux Ionisés, UMR7344, CNRS, Univ. Orléans, F-45067 Orléans (France); Ivlev, A. V.; Huber, P.; Hagl, T.; Thomas, H. M.; Morfill, G. E. [Max Planck Institute for extraterrestrial Physics, P.O. Box 1312, Giessenbachstr., 85741 Garching (Germany)] [Max Planck Institute for extraterrestrial Physics, P.O. Box 1312, Giessenbachstr., 85741 Garching (Germany); Couëdel, L. [Centre National de la Recherche Scientifique, Aix-Marseille-Université, Laboiratoire de Physique des Intéractions Ioniques et Moléculaires, UMR 7345, 13397 Marseille cedex 20 (France)] [Centre National de la Recherche Scientifique, Aix-Marseille-Université, Laboiratoire de Physique des Intéractions Ioniques et Moléculaires, UMR 7345, 13397 Marseille cedex 20 (France); Schwabe, M. [Max Planck Institute for extraterrestrial Physics, P.O. Box 1312, Giessenbachstr., 85741 Garching (Germany) [Max Planck Institute for extraterrestrial Physics, P.O. Box 1312, Giessenbachstr., 85741 Garching (Germany); Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, California 94720 (United States); Mikikian, M.; Boufendi, L. [Groupe de Recherches sur l'Energétique des Milieux Ionisés, UMR7344, CNRS, Univ. Orléans, F-45067 Orléans (France)] [Groupe de Recherches sur l'Energétique des Milieux Ionisés, UMR7344, CNRS, Univ. Orléans, F-45067 Orléans (France); Skvortsov, A. [Yuri Gagarin Cosmonauts Training Center, RU-141160 Star City (Russian Federation)] [Yuri Gagarin Cosmonauts Training Center, RU-141160 Star City (Russian Federation); Lipaev, A. M.; Molotkov, V. I.; Petrov, O. F.; Fortov, V. E. [Joint Institute for High Temperatures, RU-125412 Moscow (Russian Federation)] [Joint Institute for High Temperatures, RU-125412 Moscow (Russian Federation)

    2013-12-15T23:59:59.000Z

    Residual charges of individual microparticles forming dense clouds were measured in a RF discharge afterglow. Experiments were performed under microgravity conditions on board the International Space Station, which ensured particle levitation inside the gas volume after the plasma switch-off. The distribution of residual charges as well as the spatial distribution of charged particles across the cloud were analyzed by applying a low-frequency voltage to the electrodes and measuring amplitudes of the resulting particle oscillations. Upon “free decharging” conditions, the charge distribution had a sharp peak at zero and was rather symmetric (with charges concentrated between ?10e and +10e), yet positively and negatively charged particles were homogeneously distributed over the cloud. However, when decharging evolved in the presence of an external DC field (applied shortly before the plasma switch-off) practically all residual charges were positive. In this case, the overall charge distribution had a sharp peak at about +15e and was highly asymmetric, while the spatial distribution exhibited a significant charge gradient along the direction of the applied DC field.

  5. Formation of ozone and oxidation of methane in a direct current corona discharge

    E-Print Network [OSTI]

    Tangirala, Umashanker

    1976-01-01T23:59:59.000Z

    FORMATION OF OZONE AND OXIDATION OF METHANE IN A DIRECT CURRENT CORONA DISCHARGE A Thesis by UMASHANKER TANGIRALA Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER... OF SCIENCE May 1976 Major Subject: Chemical Engineering FORMATION OF OZONE AND OXIDATION OF METHANE IN A DIRECT CURRENT CORONA DISCHARGE A Thesis by UMASHANKER TANGIRALA Approved as to style and content by: (Chairman of Committee) ( ad of Department...

  6. DC current induced metal-insulator transition in epitaxial Sm{sub 0.6}Nd{sub 0.4}NiO{sub 3}/LaAlO{sub 3} thin film

    SciTech Connect (OSTI)

    Huang, Haoliang [Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China) [Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); CAS Key Laboratory of Materials for Energy Conversion, Department of Materials Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026 (China); Luo, Zhenlin, E-mail: zlluo@ustc.edu.cn; Yang, Yuanjun; Yang, Mengmeng; Wang, Haibo; Hu, Sixia; Bao, Jun [CAS Key Laboratory of Materials for Energy Conversion, Department of Materials Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026 (China) [CAS Key Laboratory of Materials for Energy Conversion, Department of Materials Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026 (China); National Synchrotron Radiation Laboratory and School of Nuclear Science and Technology, University of Science and Technology of China, Hefei, Anhui 230026 (China); Yun, Yu; Meng, Dechao; Lu, Yalin [CAS Key Laboratory of Materials for Energy Conversion, Department of Materials Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026 (China)] [CAS Key Laboratory of Materials for Energy Conversion, Department of Materials Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026 (China); Gao, Chen, E-mail: cgao@ustc.edu.cn [Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China) [Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); CAS Key Laboratory of Materials for Energy Conversion, Department of Materials Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026 (China); National Synchrotron Radiation Laboratory and School of Nuclear Science and Technology, University of Science and Technology of China, Hefei, Anhui 230026 (China)

    2014-05-15T23:59:59.000Z

    The metal-insulator transition (MIT) in strong correlated electron materials can be induced by external perturbation in forms of thermal, electrical, optical, or magnetic fields. We report on the DC current induced MIT in epitaxial Sm{sub 0.6}Nd{sub 0.4}NiO{sub 3} (SNNO) thin film deposited by pulsed laser deposition on (001)-LaAlO{sub 3} substrate. It was found that the MIT in SNNO film not only can be triggered by thermal, but also can be induced by DC current. The T{sub MI} of SNNO film decreases from 282 K to 200 K with the DC current density increasing from 0.003 × 10{sup 9} A•m{sup ?2} to 4.9 × 10{sup 9} A•m{sup ?2}. Based on the resistivity curves measured at different temperatures, the MIT phase diagram has been successfully constructed.

  7. Parallel electric fields in the upward current region of the aurora: Indirect and direct observations

    E-Print Network [OSTI]

    California at Berkeley, University of

    Parallel electric fields in the upward current region of the aurora: Indirect and direct In this article we present electric field, magnetic field, and charged particle observations from the upward current region of the aurora focusing on the structure of electric fields at the boundary between

  8. Sensorless Direct Torque Control For Salient Pole PMSM Based on Extended Kalman Filter Fed By AC/DC/AC Converter

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Sensorless Direct Torque Control For Salient ­ Pole PMSM Based on Extended Kalman Filter Fed By AC is proposed. The Direct Torque Control (DTC) technique for PMSM is receiving increasing attention due on the stochastic intromission, in others words, noise. The PMSM is fed by an indirect power electronic converter

  9. ELSEVIER Bioelectrochemistry and Bioenergetics 35 (1994) 99-101 Low level direct current -cell culture fibroblast model

    E-Print Network [OSTI]

    Ljubljana, University of

    ELSEVIER Bioelectrochemistry and Bioenergetics 35 (1994) 99-101 Low level direct current - cell;100 U. Batista et al. / Bioelectrochemistry and Bioenergetics 35 (1994) 99-101 2.2. Direct current

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

    SciTech Connect (OSTI)

    Litzenberger, Wayne; Lava, Val

    1994-08-01T23:59:59.000Z

    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).

  11. Integration of offshore wind farms through High Voltage Direct Current networks.

    E-Print Network [OSTI]

    Livermore, Luke

    2013-01-01T23:59:59.000Z

    ??The integration of offshore wind farms through Multi Terminal DC (MTDC) networks into the GB network was investigated. The ability of Voltage Source Converter (VSC)… (more)

  12. DC arc weld starter

    DOE Patents [OSTI]

    Campiotti, Richard H. (Tracy, CA); Hopwood, James E. (Oakley, CA)

    1990-01-01T23:59:59.000Z

    A system for starting an arc for welding uses three DC power supplies, a high voltage supply for initiating the arc, an intermediate voltage supply for sustaining the arc, and a low voltage welding supply directly connected across the gap after the high voltage supply is disconnected.

  13. Ozone generation by negative direct current corona discharges in dry air fed coaxial wire-cylinder reactors

    SciTech Connect (OSTI)

    Yehia, Ashraf [Department of Physics, Faculty of Science, Assiut University, Assiut 71516, Egypt and Department of Physics, College of Science and Humanitarian Studies in Alkharj, Salman bin Abdulaziz University, P.O. Box 83, Alkharj 11942 (Saudi Arabia)] [Department of Physics, Faculty of Science, Assiut University, Assiut 71516, Egypt and Department of Physics, College of Science and Humanitarian Studies in Alkharj, Salman bin Abdulaziz University, P.O. Box 83, Alkharj 11942 (Saudi Arabia); Mizuno, Akira [Department of Environmental and Life Sciences, Toyohashi University of Technology, Tempaku-cho, Toyohashi 441-8580 (Japan)] [Department of Environmental and Life Sciences, Toyohashi University of Technology, Tempaku-cho, Toyohashi 441-8580 (Japan)

    2013-05-14T23:59:59.000Z

    An analytical study was made in this paper for calculating the ozone generation by negative dc corona discharges. The corona discharges were formed in a coaxial wire-cylinder reactor. The reactor was fed by dry air flowing with constant rates at atmospheric pressure and room temperature, and stressed by a negative dc voltage. The current-voltage characteristics of the negative dc corona discharges formed inside the reactor were measured in parallel with concentration of the generated ozone under different operating conditions. An empirical equation was derived from the experimental results for calculating the ozone concentration generated inside the reactor. The results, that have been recalculated by using the derived equation, have agreed with the experimental results over the whole range of the investigated parameters, except in the saturation range for the ozone concentration. Therefore, the derived equation represents a suitable criterion for expecting the ozone concentration generated by negative dc corona discharges in dry air fed coaxial wire-cylinder reactors under any operating conditions in range of the investigated parameters.

  14. The MAPS Program in the Pacific Northwest: Current Status and Future Direction

    E-Print Network [OSTI]

    DeSante, David F.

    The MAPS Program in the Pacific Northwest: Current Status and Future Direction Report Submitted #12;#12;The MAPS Program in the Pacific Northwest - i TABLE OF CONTENTS EXECUTIVE SUMMARY........................................................................................................................................... 10 Adult Capture Rates and Station Longevity at MAPS Stations in the Pacific Northwest Region

  15. Chemical Vapor Deposition of Silicon Dioxide by Direct-Current Corona Discharges in Dry Air

    E-Print Network [OSTI]

    Chen, Junhong

    Chemical Vapor Deposition of Silicon Dioxide by Direct-Current Corona Discharges in Dry Air, Si4O4(CH3)8) widely used as additives in personal care products. In both photocopiers and air in indoor air, the gas-phase processes limit the rate of deposition. KEY WORDS: Corona plasma; corona

  16. Growth of tungsten nanoparticles in direct-current argon glow discharges

    SciTech Connect (OSTI)

    Kishor Kumar, K.; Coueedel, L.; Arnas, C. [Laboratoire de Physique des Interactions Ioniques et Moleculaires, CNRS-Aix-Marseille Universite, 13397 Marseille (France)

    2013-04-15T23:59:59.000Z

    The growth of nanoparticles from the sputtering of a tungsten cathode in DC argon glow discharges is reported. The study was performed at fixed argon pressure and constant discharge current. The growth by successive agglomerations is evidenced. First, tungsten nanocrystallites agglomerate into primary particles, the most probable size of which being {approx}30 nm. Primary particles of this size are observed for all plasma durations and always remain the most numerous in the discharge. Primary particles quickly agglomerate to form particles with size up to {approx}150 nm. For short plasma duration, log-normal functions describe accurately the dust particle size distributions. On the contrary, for long discharge durations, a second hump appears in the distributions toward large particle sizes. In the meantime, the discharge voltage, electron density, and emission line intensities strongly evolve. Their evolutions can be divided in four separate phases and exhibit unusual distinctive features compared to earlier observations in discharges in which particles were growing. The evolution of the different parameters is explained by a competition between the surface state of the tungsten cathode and the influence of the growing nanoparticles. The differences with sputtering glow discharges and chemically active plasmas suggest that the nanoparticle growth and its influence on discharge parameters is system and material dependent.

  17. High efficiency resonant dc/dc converter for solar power applications

    E-Print Network [OSTI]

    Inam, Wardah

    2013-01-01T23:59:59.000Z

    This thesis presents a new topology for a high efficiency dc/dc resonant power converter that utilizes a resistance compression network to provide simultaneous zero voltage switching and near zero current switching across ...

  18. Hall mobility of cuprous oxide thin films deposited by reactive direct-current magnetron sputtering

    E-Print Network [OSTI]

    Lee, Yun Seog

    Cuprous oxide (Cu[subscript 2]O) is a promising earth-abundant semiconductor for photovoltaic applications. We report Hall mobilities of polycrystalline Cu[subscript 2]O thin films deposited by reactive dc magnetron ...

  19. Structure formation upon reactive direct current magnetron sputtering of transition metal oxide films

    SciTech Connect (OSTI)

    Ngaruiya, J.M.; Kappertz, O.; Mohamed, S.H.; Wuttig, M. [I. Physikalisches Institut der RWTH Aachen, D-52056 Aachen, Germany and Jomo Kenyatta University of Agriculture and Technology, Box 62000 Nairobi (Kenya); I. Physikalisches Institut der RWTH Aachen, D-52056 Aachen (Germany)

    2004-08-02T23:59:59.000Z

    A comparative study of reactive direct current magnetron sputtering for different transition metal oxides reveals crystalline films at room temperature for group 4 and amorphous films for groups 5 and 6. This observation cannot be explained by the known growth laws and is attributed to the impact of energetic particles, originating from the oxidized target, on the growing film. This scenario is supported by measured target characteristics, the evolution of deposition stress of the films, and the observed backsputtering.

  20. A Multi-Level Grid Interactive Bi-directional AC/DC-DC/AC Converter and a Hybrid Battery/Ultra-capacitor Energy Storage System with Integrated Magnetics for Plug-in Hybrid Electric Vehicles

    SciTech Connect (OSTI)

    Onar, Omer C [ORNL] [ORNL

    2011-01-01T23:59:59.000Z

    This study presents a bi-directional multi-level power electronic interface for the grid interactions of plug-in hybrid electric vehicles (PHEVs) as well as a novel bi-directional power electronic converter for the combined operation of battery/ultracapacitor hybrid energy storage systems (ESS). The grid interface converter enables beneficial vehicle-to-grid (V2G) interactions in a high power quality and grid friendly manner; i.e, the grid interface converter ensures that all power delivered to/from grid has unity power factor and almost zero current harmonics. The power electronic converter that provides the combined operation of battery/ultra-capacitor system reduces the size and cost of the conventional ESS hybridization topologies while reducing the stress on the battery, prolonging the battery lifetime, and increasing the overall vehicle performance and efficiency. The combination of hybrid ESS is provided through an integrated magnetic structure that reduces the size and cost of the inductors of the ESS converters. Simulation and experimental results are included as prove of the concept presenting the different operation modes of the proposed converters.

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

    SciTech Connect (OSTI)

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

    1996-12-31T23:59:59.000Z

    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.

  2. 3D direct and inverse solvers for eddy current testing of deposits in steam generator

    E-Print Network [OSTI]

    Haddar, Houssem

    2014-01-01T23:59:59.000Z

    We consider the inverse problem of estimating the shape profile of an unknown deposit from a set of eddy current impedance measurements. The measurements are acquired with an axial probe, which is modeled by a set of coils that generate a magnetic field inside the tube. For the direct problem, we validate the method that takes into account the tube support plates, highly conductive part, by a surface impedance condition. For the inverse problem, finite element and shape sensitivity analysis related to the eddy current problem are provided in order to determine the explicit formula of the gradient of a least square misfit functional. A geometrical-parametric shape inversion algorithm based on cylindrical coordinates is designed to improve the robustness and the quality of the reconstruction. Several numerical results are given in the experimental part. Numerical experiments on synthetic deposits, nearby or far away from the tube, with different shapes are considered in the axisymmetric configuration.

  3. Light-weight DC to very high voltage DC converter

    DOE Patents [OSTI]

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

    1998-01-01T23:59:59.000Z

    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.

  4. Light-weight DC to very high voltage DC converter

    DOE Patents [OSTI]

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

    1998-06-30T23:59:59.000Z

    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.

  5. Triple voltage dc-to-dc converter and method

    DOE Patents [OSTI]

    Su, Gui-Jia (Knoxville, TN)

    2008-08-05T23:59:59.000Z

    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.

  6. Structural properties of dusty plasma in direct current and radio frequency gas discharges

    SciTech Connect (OSTI)

    Ramazanov, T. S.; Dzhumagulova, K. N.; Jumabekov, A. N.; Dosbolayev, M. K. [Al Farabi Kazakh National University, IETP, Tole bi 96a, Almaty, 050012 (Kazakhstan)

    2008-05-15T23:59:59.000Z

    This paper presents radial distribution functions of dust particles obtained experimentally in dc and rf discharges. Pressure and interaction energy of dusty particles were calculated on the basis of these functions. The Langevin dynamics computer simulation for each experiment was performed. The comparisons with computer simulations are made.

  7. The Use of DC Glow Discharges as Undergraduate Educational Tools

    SciTech Connect (OSTI)

    Stephanie A. Wissel and Andrew Zwicker, Jerry Ross, and Sophia Gershman

    2012-10-09T23:59:59.000Z

    Plasmas have a beguiling way of getting students excited and interested in physics. We argue that plasmas can and should be incorporated into the undergraduate curriculum as both demonstrations and advanced investigations of electromagnetism and quantum effects. Our device, based on a direct current (DC) glow discharge tube, allows for a number of experiments into topics such as electrical breakdown, spectroscopy, magnetism, and electron temperature.

  8. Investigation of DC distribution by measuring and modelling power supply devices for buildings with PV

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    requiring power transformation components. Since any type of load can be potentially fed with direct current panels without any power transformation seems to be obvious, nevertheless, precise simulations needInvestigation of DC distribution by measuring and modelling power supply devices for buildings

  9. Lightweight PV Inverters: Dual Bi-Directional IGBTs Modules Enables Breakthrough PV Inverter Using Current Modulation Topology

    SciTech Connect (OSTI)

    None

    2012-01-30T23:59:59.000Z

    Solar ADEPT Project: PV inverters convert DC power generated by modules into usable AC power. IPC’s initial 30kW 94lb. PV inverter reduces the weight of comparable 30kW PV inverters by 90%—reducing the cost of materials, manufacturing, shipping, and installation. With ARPA-E support, new bi-directional silicon power switches will be developed, commercialized, and utilized in IPC’s next-generation PV inverter. With these components, IPC will produce 100kW inverters that weight less than 100lb., reducing the weight of conventional 3,000lb. 100kW inverters by more than 95%. The new power switches will cut IPC’s $/W manufacturing cost in half, as well as further reduce indirect shipping and installation costs.

  10. Nonlocal control of electron temperature in short direct current glow discharge plasma

    SciTech Connect (OSTI)

    Demidov, V. I. [Department of Optics and Spectroscopy, St. Petersburg State University, St. Petersburg 199034 (Russian Federation); International Laboratory “Nonlocal Plasma in Nanotechnology and Medicine”, ITMO University, Kronverkskiy pr. 49, St. Petersburg 197101 (Russian Federation); Department of Physics and Astronomy, West Virginia University, Morgantown, West Virginia 26506 (United States); Kudryavtsev, A. A.; Stepanova, O. M. [Department of Optics and Spectroscopy, St. Petersburg State University, St. Petersburg 199034 (Russian Federation); Kurlyandskaya, I. P. [International Laboratory “Nonlocal Plasma in Nanotechnology and Medicine”, ITMO University, Kronverkskiy pr. 49, St. Petersburg 197101 (Russian Federation); St. Petersburg University of State Fire Service of EMERCOM RF, Murmansk Branch, Murmansk 183040 (Russian Federation)

    2014-09-15T23:59:59.000Z

    To demonstrate controlling the electron temperature in nonlocal plasma, experiments have been performed on a short (without positive column) dc glow discharge with a cold cathode by applying different voltages to the conducting discharge wall. The experiments have been performed for low-pressure noble gas discharges. The applied voltage can modify trapping the energetic electrons emitted from the cathode sheath and arising from the atomic and molecular processes in the plasma within the device volume. This phenomenon results in the energetic electrons heating the slow plasma electrons, which consequently modifies the electron temperature. Furthermore, a numerical model of the discharge has demonstrated the electron temperature modification for the above case.

  11. Mechanism of direct current electrical charge conduction in p-toluenesulfonate doped polypyrrole/carbon composites

    SciTech Connect (OSTI)

    Kumar, Amit [National Physical Laboratory, Council of Scientific and Industrial Research, Dr. K. S. Krishnan Marg, New Delhi 110012 (India); Department of Chemistry, Banaras Hindu University, Varanasi 221005 (India); Singh, Rajiv K.; Singh, Hari K.; Singh, Ramadhar, E-mail: ramadhar@mail.nplindia.org [National Physical Laboratory, Council of Scientific and Industrial Research, Dr. K. S. Krishnan Marg, New Delhi 110012 (India); Srivastava, Pankaj [Department of Chemistry, Banaras Hindu University, Varanasi 221005 (India)

    2014-03-14T23:59:59.000Z

    Polypyrrole/carbon (PPy/C) composites have been synthesized using varying concentration of p-toluenesulfonate (pTS) dopant by surface initiated in-situ chemical oxidative polymerization. The synthesis and influence of pTS on the structure of the PPy/C composites are confirmed by Fourier transform infrared studies and the morphological features have been examined by scanning electron microscopy. X-ray photoelectron spectroscopy, employed to examine the surface composition and doping level of these composites, confirms the anionic doping into the polymer backbone. Electron spin resonance measurement has been carried out on these samples to identify the nature of the charge carriers and their concentration at different doping levels. The dc electrical conductivity of these composites has been measured in the temperature range ?10–305?K. The observed results have been analyzed in the framework of existing theoretical models. Different Mott's parameters, such as characteristic temperature (T{sub 0}), density of states at the Fermi level (N(E{sub F})), average hopping distance (R), and average hopping energy (W), evaluated from dc conductivity data supports the applicability of Mott's three dimensional variable range hopping mechanism in this system.

  12. The case for a directional dark matter detector and the status of current experimental efforts

    E-Print Network [OSTI]

    Battat, James

    We present the case for a dark matter detector with directional sensitivity. This document was developed at the 2009 CYGNUS workshop on directional dark matter detection, and contains contributions from theorists and ...

  13. Effects of Transcranial Direct Current Stimulation (tDCS) on Human Memory.

    SciTech Connect (OSTI)

    Matzen, Laura E.; Trumbo, Michael Christopher Stefan

    2014-10-01T23:59:59.000Z

    Training a person in a new knowledge base or skill set is extremely time consuming and costly, particularly in highly specialized domains such as the military and the intelligence community. Recent research in cognitive neuroscience has suggested that a technique called transcranial direct current stimulation (tDCS) has the potential to revolutionize training by enabling learners to acquire new skills faster, more efficiently, and more robustly (Bullard et al., 2011). In this project, we tested the effects of tDCS on two types of memory performance that are critical for learning new skills: associative memory and working memory. Associative memory is memory for the relationship between two items or events. It forms the foundation of all episodic memories, so enhancing associative memory could provide substantial benefits to the speed and robustness of learning new information. We tested the effects of tDCS on associative memory, using a real-world associative memory task: remembering the links between faces and names. Working memory refers to the amount of information that can be held in mind and processed at one time, and it forms the basis for all higher-level cognitive processing. We investigated the degree of transfer between various working memory tasks (the N-back task as a measure of verbal working memory, the rotation-span task as a measure of visuospatial working memory, and Raven's progressive matrices as a measure of fluid intelligence) in order to determine if tDCS-induced facilitation of performance is task-specific or general.

  14. Summary of electric vehicle dc motor-controller tests

    SciTech Connect (OSTI)

    McBrien, E F; Tryon, H B

    1982-09-01T23:59:59.000Z

    Available performance data for production motors are usually of marginal value to the electric vehicle designer. To provide at least a partial remedy to this situation, tests of typical dc propulsion motors and controllers were conducted as part of the DOE Electric Vehicle Program. The objectives of this program were to evaluate the differences in the performance of dc motors when operating with chopper-type controllers and when operating on direct current; and to gain an understanding of the interactions between the motor and the controller which cause these differences. Toward this end, motor-controller tests performed by the NASA Lewis Research Center provided some of the first published data that quantified motor efficiency variations for both ripple-free (straight dc) and chopper modes of operation. Test and analysis work at the University of Pittsburgh explored motor-controller relationships in greater depth. And to provide additional data, 3E Vehicles tested two small motors, both on a dynamometer and in a vehicle, and the Eaton Corporation tested larger motors, using sophisticated instrumentation and digital processing techniques. All the motors tested were direct-current types. Of the separately excited types, seven were series wound and two were shunt wound. One self-excited permanent magnet type was also tested. Four of the series wound motors used brush shifting to obtain good commutation. In almost all cases, controller limitations constrained the test envelope so that the full capability of the motors could not be explored.

  15. Cancer Stem Cells--Perspectives on Current Status and Future Directions: AACR Workshop on Cancer Stem Cells

    E-Print Network [OSTI]

    Wahl, Geoffrey M.

    Cancer Stem Cells--Perspectives on Current Status and Future Directions: AACR Workshop on Cancer Hospital for Sick Children, Toronto, Ontario, Canada; 4 Terry Fox Laboratory BC Cancer Research Center, Vancouver, British Columbia, Canada; 5 Moores University of California San Diego Cancer Center; 6 The Salk

  16. FC/Battery Power Management for Electric Vehicle Based Interleaved dc-dc Boost Converter Topology

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    FC/Battery Power Management for Electric Vehicle Based Interleaved dc- dc Boost Converter Topology power systems in electric vehicle application, in order to decrease the FC current ripple. Therefore the performance of the FC system during transient and instantaneous peak power demands in electric vehicle

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

    E-Print Network [OSTI]

    Pham, Van Sang

    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 ...

  18. DC source assemblies

    DOE Patents [OSTI]

    Campbell, Jeremy B; Newson, Steve

    2013-02-26T23:59:59.000Z

    Embodiments of DC source assemblies of power inverter systems of the type suitable for deployment in a vehicle having an electrically grounded chassis are provided. An embodiment of a DC source assembly comprises a housing, a DC source disposed within the housing, a first terminal, and a second terminal. The DC source also comprises a first capacitor having a first electrode electrically coupled to the housing, and a second electrode electrically coupled to the first terminal. The DC source assembly further comprises a second capacitor having a first electrode electrically coupled to the housing, and a second electrode electrically coupled to the second terminal.

  19. A Decentralized Protection Scheme for Converters Utilizing a DC-link Inductor

    E-Print Network [OSTI]

    Lipo, Thomas

    - as in HVDC transmission for example - as well as in DC-links for high-power current source inverters

  20. Directions

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

    Directions Where We Are Directions The Bradbury Science Museum is located at 1350 Central Avenue Los Alamos, NM 87544 Los Alamos (elevation 7,355 feet) is perched high atop the...

  1. Recent developments and future directions Coherently controlled electrical currents at surfaces

    E-Print Network [OSTI]

    of ultrashort current pulses at surfaces. Two phase-locked laser pulses with carrier frequencies a and a/2 of the electrons due to vibronic or electronic excitation within the junction can be neglected. In this regime e­ Metal Sample Excitations Pulses =90° Time­Delayt PhotoemissionPulse Photoelectrons 0.0 0.5 1

  2. Accelerated Status Exceptionally promising current UCI undergraduate Engineering students may petition for streamlined admission directly

    E-Print Network [OSTI]

    Mease, Kenneth D.

    Accelerated Status Exceptionally promising current UCI undergraduate Engineering students may numbered 200-289. How to Petition: Students are required to submit an Accelerated Status Petition Form) to the Graduate Student Affairs Office (5400 Engineering Hall). Students may join the Accelerated Status at any

  3. Accelerated Status Exceptionally promising current UCI undergraduate Engineering students may petition for streamlined admission directly

    E-Print Network [OSTI]

    Mease, Kenneth D.

    Accelerated Status Exceptionally promising current UCI undergraduate Engineering students may numbered 200-289. How to Petition: Students are required to submit an Accelerated Status Petition Form) to the Graduate Student Affairs Office (305 Rockwell Engineering Center). Students may join the Accelerated Status

  4. Oscillation modes of direct current microdischarges with parallel-plate geometry

    SciTech Connect (OSTI)

    Stefanovic, Ilija; Kuschel, Thomas; Winter, Joerg [Institut fuer Experimentalphysik II, Ruhr-Universitaet Bochum, 44781 Bochum (Germany); Skoro, Nikola; Maric, Dragana; Petrovic, Zoran Lj [Institute of Physics, University of Belgrade, POB 68, 11080 Belgrade (Serbia)

    2011-10-15T23:59:59.000Z

    Two different oscillation modes in microdischarge with parallel-plate geometry have been observed: relaxation oscillations with frequency range between 1.23 and 2.1 kHz and free-running oscillations with 7 kHz frequency. The oscillation modes are induced by increasing power supply voltage or discharge current. For a given power supply voltage, there is a spontaneous transition from one to other oscillation mode and vice versa. Before the transition from relaxation to free-running oscillations, the spontaneous increase of oscillation frequency of relaxation oscillations form 1.3 kHz to 2.1 kHz is measured. Fourier transform spectra of relaxation oscillations reveal chaotic behavior of microdischarges. Volt-ampere (V-A) characteristics associated with relaxation oscillations describes periodical transition between low current, diffuse discharge, and normal glow. However, free-running oscillations appear in subnormal glow only.

  5. Bi-directional dc-dc Converter | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarly Career Scientists' ResearchTheMarketing,Energy and NaturalBethel ValleyMembershipThe

  6. Bi-directional dc-dc Converter | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-Up fromDepartmentTie Ltd: ScopeDepartment1, 2011 DRAFTof Energy Beyond10 DOE Vehicle

  7. Bi-directional dc-dc Converter | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-Up fromDepartmentTie Ltd: ScopeDepartment1, 2011 DRAFTof Energy Beyond10 DOE

  8. Building Scale DC Microgrids

    E-Print Network [OSTI]

    Marnay, Chris

    2013-01-01T23:59:59.000Z

    resources, a 10 kW vertical axis wind turbine, and Fig. 4AC-grid Fig. 3. Vertical axis wind turbine in the AIT DC µ

  9. Building Scale DC Microgrids

    E-Print Network [OSTI]

    Marnay, Chris

    2014-01-01T23:59:59.000Z

    resources, a 10 kW vertical axis wind turbine, and Fig. 4the µgrid Fig. 3. Vertical axis wind turbine in the AIT DC µ

  10. RES D.C.

    Broader source: Energy.gov [DOE]

    RES DC, hosted by the National Center for American Indian Enterprise Development (The National Center), will feature access to respected tribal leaders, members of congress, federal agency...

  11. Direct imaging of neural currents using ultra-low field magnetic resonance techniques

    DOE Patents [OSTI]

    Volegov, Petr L. (Los Alamos, NM); Matlashov, Andrei N. (Los Alamos, NM); Mosher, John C. (Los Alamos, NM); Espy, Michelle A. (Los Alamos, NM); Kraus, Jr., Robert H. (Los Alamos, NM)

    2009-08-11T23:59:59.000Z

    Using resonant interactions to directly and tomographically image neural activity in the human brain using magnetic resonance imaging (MRI) techniques at ultra-low field (ULF), the present inventors have established an approach that is sensitive to magnetic field distributions local to the spin population in cortex at the Larmor frequency of the measurement field. Because the Larmor frequency can be readily manipulated (through varying B.sub.m), one can also envision using ULF-DNI to image the frequency distribution of the local fields in cortex. Such information, taken together with simultaneous acquisition of MEG and ULF-NMR signals, enables non-invasive exploration of the correlation between local fields induced by neural activity in cortex and more `distant` measures of brain activity such as MEG and EEG.

  12. EIS-0450: TransWest Express 600 kV Direct Current Transmission Project in Wyoming, Colorado, Utah, and Nevada

    Broader source: Energy.gov [DOE]

    This EIS, being prepared jointly by DOE’s Western Area Power Administration and the Department of the Interior’s Bureau of Land Management (Wyoming State Office), evaluates the environmental impacts of granting a right-of-way for the TransWest Express 600-kilovolt Direct Current Transmission Project and amending a land use plan. The project consists of an overhead transmission line that would extend approximately 725 miles from south-central Wyoming, through Colorado and Utah. Western proposes to be a joint owner of the project.

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

    SciTech Connect (OSTI)

    NONE

    2005-07-01T23:59:59.000Z

    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.

  14. Control of a Fuel-Cell Powered DC Electric Vehicle Motor

    E-Print Network [OSTI]

    Skogestad, Sigurd

    Control of a Fuel-Cell Powered DC Electric Vehicle Motor Federico Zenith Sigurd Skogestad of a Fuel-Cell Powered DC Electric Vehicle Motor #12;3 Currently Available Models and Control Strategies Skogestad, Control of a Fuel-Cell Powered DC Electric Vehicle Motor #12;3 Currently Available Models

  15. Strategic Directions for Hydrogen Delivery Workshop Proceedings

    Broader source: Energy.gov [DOE]

    Proceedings from the Strategic Directions for Hydrogen Delivery Workshop held May 7-8, 2003 in Washington, DC. Author: Energetics

  16. Direct

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed Newcatalyst phasesData FilesShape,PhysicsDileepDirac Charge Dynamcs inDirect

  17. High voltage DC power supply

    DOE Patents [OSTI]

    Droege, T.F.

    1989-12-19T23:59:59.000Z

    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.

  18. High voltage DC power supply

    DOE Patents [OSTI]

    Droege, Thomas F. (Batavia, IL)

    1989-01-01T23:59:59.000Z

    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.

  19. Direct and indirect capture of carriers into the lasing ground state and the light-current characteristic of quantum dot lasers

    SciTech Connect (OSTI)

    Wu, Yuchang, E-mail: yuchangw@vt.edu; Asryan, Levon V., E-mail: asryan@vt.edu [Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061 (United States)

    2014-03-14T23:59:59.000Z

    We calculate the light-current characteristic (LCC) of a quantum dot (QD) laser under the conditions of both direct and indirect capture of carriers from the optical confinement layer into the lasing ground state in QDs. We show that direct capture is a dominant process determining the ground-state LCC. Only when direct capture is slow, the role of indirect capture (capture into the QD excited state and subsequent intradot relaxation to the ground state) becomes important.

  20. DC-DC converter current source fed naturally commutated brushless DC motor drive

    E-Print Network [OSTI]

    Khopkar, Rahul Vijaykumar

    2004-11-15T23:59:59.000Z

    ..............................................................................................1 2 Commutator and brushes.......................................................................................2 3 Back-emf of a three-phase PMSM........................................................................3 4 Power generated... machines and are usually called Permanent Magnet Synchronous Machine (PMSM). In PMSM machines, the slip rings are eliminated and the stator windings are equivalent to the stator windings in synchronous ac machines. While no power is required for field...

  1. Multiplatform Dynamic System Simulation of a DC-DC Converter.

    E-Print Network [OSTI]

    Song, Wenpeng

    2012-01-01T23:59:59.000Z

    ??The work presented in this paper focuses on the usability testing for the Open-Modelica. The modeling and simulation of the BMR450 DC-DC converter is also… (more)

  2. A global maximum power point tracking DC-DC converter

    E-Print Network [OSTI]

    Duncan, Joseph, 1981-

    2005-01-01T23:59:59.000Z

    This thesis describes the design, and validation of a maximum power point tracking DC-DC converter capable of following the true global maximum power point in the presence of other local maximum. It does this without the ...

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

    SciTech Connect (OSTI)

    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

    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.

  4. Active dc filter for HVDC system--A test installation in the Konti-Skan DC link at Lindome converter station

    SciTech Connect (OSTI)

    Zhang, Wenyan; Asplund, G. (ABB Power Systems, Ludvika (Sweden). HVDC Division); Aberg, A. (ABB Corporate Research, Lund (Sweden). Dept. of Man-Machine Communication); Jonsson, U. (Svenska Kraftnaet, Vaellingby (Sweden)); Loeoef, O. (Vattenfall AB, Trollhaettan (Sweden). Region Vaestsverige)

    1993-07-01T23:59:59.000Z

    The purpose of introducing active dc filters is to meet the more and more stringent requirement from power utilities on limiting telephone interference caused by harmonic currents from HVdc transmission lines, without unnecessarily increasing the cost of HVdc stations. An active dc filter installed in the Konti-Skan HVdc link is described. The active dc filter is connected at the bottom of an existing passive dc filter at the Lindome station. The active dc filter includes optic harmonic current measuring unit, control system, protection and supervision system, PWM power amplifier, high-frequency transformer, surge arrester, and coupling apparatuses. The active dc filter has small physical size and occupies small ground area. The performance of the active dc filter for eliminating the disturbing harmonics is excellent. To achieve comparable results by passive filters would require something like ten times more high voltage equipment.

  5. Conversion of pure spin current to charge current in amorphous bismuth

    SciTech Connect (OSTI)

    Emoto, H.; Ando, Y.; Shinjo, T.; Shiraishi, M., E-mail: shiraishi@ee.es.osaka-u.ac.jp [Graduate School of Engineering Science, Osaka University, Osaka 560-8531 (Japan); Shikoh, E. [Graduate School of Engineering, Osaka City University, Osaka 558-8585 (Japan); Fuseya, Y. [Department of Applied Physics and Chemistry, The University of Electro-Communications, Tokyo 182-8585 (Japan)

    2014-05-07T23:59:59.000Z

    Spin Hall angle and spin diffusion length in amorphous bismuth (Bi) are investigated by using conversion of a pure spin current to a charge current in a spin pumping technique. In Bi/Ni{sub 80}Fe{sub 20}/Si(100) sample, a clear direct current (DC) electromotive force due to the inverse spin Hall effect of the Bi layer is observed at room temperature under a ferromagnetic resonance condition of the Ni{sub 80}Fe{sub 20} layer. From the Bi thickness dependence of the DC electromotive force, the spin Hall angle and the spin diffusion length of the amorphous Bi film are estimated to be 0.02 and 8?nm, respectively.

  6. Beam current sensor

    DOE Patents [OSTI]

    Kuchnir, M.; Mills, F.E.

    1984-09-28T23:59:59.000Z

    A current sensor for measuring the dc component of a beam of charged particles employs a superconducting pick-up loop probe, with twisted superconducting leads in combination with a Superconducting Quantum Interference Device (SQUID) detector. The pick-up probe is in the form of a single-turn loop, or a cylindrical toroid, through which the beam is directed and within which a first magnetic flux is excluded by the Meisner effect. The SQUID detector acts as a flux-to-voltage converter in providing a current to the pick-up loop so as to establish a second magnetic flux within the electrode which nulls out the first magnetic flux. A feedback voltage within the SQUID detector represents the beam current of the particles which transit the pick-up loop. Meisner effect currents prevent changes in the magnetic field within the toroidal pick-up loop and produce a current signal independent of the beam's cross-section and its position within the toroid, while the combination of superconducting elements provides current measurement sensitivities in the nano-ampere range.

  7. Beam current sensor

    DOE Patents [OSTI]

    Kuchnir, Moyses (Elmhurst, IL); Mills, Frederick E. (Elburn, IL)

    1987-01-01T23:59:59.000Z

    A current sensor for measuring the DC component of a beam of charged particles employs a superconducting pick-up loop probe, with twisted superconducting leads in combination with a Superconducting Quantum Interference Device (SQUID) detector. The pick-up probe is in the form of a single-turn loop, or a cylindrical toroid, through which the beam is directed and within which a first magnetic flux is excluded by the Meisner effect. The SQUID detector acts as a flux-to-voltage converter in providing a current to the pick-up loop so as to establish a second magnetic flux within the electrode which nulls out the first magnetic flux. A feedback voltage within the SQUID detector represents the beam current of the particles which transit the pick-up loop. Meisner effect currents prevent changes in the magnetic field within the toroidal pick-up loop and produce a current signal independent of the beam's cross-section and its position within the toroid, while the combination of superconducting elements provides current measurement sensitivites in the nano-ampere range.

  8. Performance test results for the Eaton dc developmental power train in an electric test bed vehicle

    SciTech Connect (OSTI)

    Crumley, R.L.; Donaldson, M.R.

    1987-09-01T23:59:59.000Z

    This report presents the results of the tests performed on a direct current (dc) power train in a test bed vehicle developed by the Eaton Corporation for the US Department of Energy (DOE). The tests were performed by EG and G Idaho, Inc. at the Idaho National Engineering Laboratory (INEL). The purpose of the INEL testing was to provide test results from which an evaluation of the performance capabilities of the Eaton dc power train could be made and compared with other vehicle propulsion systems. The planned tests were primarily oriented toward road testing, chassis dynamometer testing, and associated dynamometer coastdown tests for road loss determination. Range tests of the Eaton dc test bed vehicle using an ALCO 2200 lead acid battery pack, produced ranges of 97 km at 56 km/h (60 miles at 35 mph), 79 km at 72 km/h (49 miles at 45 mph), and 47 km at 88 km/h (29 miles at 55 mph). The corresponding net dc energy consumptions are 135 Wh/km (217 Wh/mile), 145 Wh/km (233 Wh/mile), and 178 Wh/km (287 Wh/mile). The energy consumption for the D-cycle test was 241 Wh/km (387 Wh/mile). 8 refs., 11 figs., 16 tabs.

  9. Sustainable Energy Utility- D.C. Home Performance (District of Columbia)

    Broader source: Energy.gov [DOE]

    The District of Columbia Sustainable Energy Utility currently offers the D.C. Home Performance program (DCHP). DCHP provides a $500 incentive to properties which successfully complete qualifying...

  10. Experimental observation of the behaviour of cogenerated dusty plasma using a bipolar pulsed direct current power supply

    SciTech Connect (OSTI)

    Sarkar, Sanjib; Bose, M. [Department of Physics, Jadavpur University, Kolkata 700032 (India); Pramanik, J. [Kharagpur College, Kharagpur 721305, West Bengal (India); Mukherjee, S. [FCIPT, Institute for Plasma Research, Gandhinagar 382428 (India)

    2013-02-15T23:59:59.000Z

    We have experimentally observed the behaviour of cogenerated dusts in unmagnetized plasma produced using a bipolar pulsed dc power supply. In this experiment, the dust particles have been generated through sputtering of graphite cathode and were stratified between two electrodes. This stratification of dust clouds has obtained at a typical range of plasma parameters, namely, 650 V (peak-to-peak) with 0.2 mbar pressure. In above condition, we detected the Taylor-like instability at the interface of two dusty clouds with different densities. A very less dust density (void like) region inside the lesser dust density portion is also noted. Again, it has been observed that a self excited dust density wave propagates towards the higher density dust fluid inside the system as well as a stationary band structure of thin multiple layers of dust particles when we apply a higher voltage (750 V peak-to-peak). The wavelength, phase velocity, and frequency of the excited wave have also been estimated.

  11. Currently, there is a substantial research and development effort directed toward optical signal processing and electronic signal processing for fiber-optic communications. Much of the work

    E-Print Network [OSTI]

    Wu, Shin-Tson

    Abstract Currently, there is a substantial research and development effort directed toward optical signal processing and electronic signal processing for fiber-optic communications. Much of the work for telecommunication services. For optical signal proc- essing, a variety of approaches are available for implementing

  12. Historical Material Analysis of DC745U Pressure Pads

    SciTech Connect (OSTI)

    Ortiz-Acosta, Denisse [Los Alamos National Laboratory

    2012-07-30T23:59:59.000Z

    As part of the Enhance Surveillance mission, it is the goal to provide suitable lifetime assessment of stockpile materials. This report is an accumulation of historical publication on the DC745U material and their findings. It is the intention that the B61 LEP program uses this collection of data to further develop their understanding and potential areas of study. DC745U is a commercially available silicone elastomer consisting of dimethyl, methyl-phenyl, and methyl-vinyl siloxane repeat units. Originally, this material was manufactured by Dow Corning as Silastic{reg_sign} DC745U at their manufacturing facility in Kendallville, IN. Recently, Dow Corning shifted this material to the Xiameter{reg_sign} brand product line. Currently, DC745U is available through Xiameter{reg_sign} or Dow Corning's distributor R. D. Abbott Company. DC745U is cured using 0.5 wt% vinyl-specific peroxide curing agent known as Luperox 101 or Varox DBPH-50. This silicone elastomer is used in numerous parts, including two major components (outer pressure pads and aft cap support) in the W80 and as pressure pads on the B61. DC745U is a proprietary formulation, thus Dow Corning provides limited information on its composition and properties. Based on past experience with Dow Corning, DC745U is at risk of formulation changes without notification to the costumer. A formulation change for DC745U may have a significant impact because the network structure is a key variable in determining material properties. The purpose of this report is to provide an overview of historical DC745U studies and identify gaps that need to be addressed in future work. Some of the previous studies include the following: 1. Spectroscopic characterization of raw gum stock. 2. Spectroscopic, thermal, and mechanical studies on cured DC745U. 3. Nuclear Magnetic Resonance (NMR) and solvent swelling studies on DC745U with different crosslink densities. 4. NMR, solvent swelling, thermal, and mechanical studies on thermally aged DC745U. 5. NMR, solvent swelling, thermal, and mechanical studies on radiolytically aged DC745U. Each area is reviewed and further work is suggested to improve our understanding of DC745U for systems engineering, surveillance, aging assessments, and lifetime assessment.

  13. A High Efficiency DC-DC Converter Topology Suitable for Distributed Large Commercial and Utility Scale PV Systems

    SciTech Connect (OSTI)

    Mohammed S. Agamy; Maja Harfman-Todorovic; Ahmed Elasser; Robert L. Steigerwald; Juan A. Sabate; Song Chi; Adam J. McCann; Li Zhang; Frank Mueller

    2012-09-01T23:59:59.000Z

    In this paper a DC-DC power converter for distributed photovoltaic plant architectures is presented. The proposed converter has the advantages of simplicity, high efficiency, and low cost. High efficiency is achieved by having a portion of the input PV power directly fed forward to the output without being processed by the converter. The operation of this converter also allows for a simplified maximum power point tracker design using fewer measurements

  14. EE443L: Intermediate Control Lab Lab2: Modeling a DC motor

    E-Print Network [OSTI]

    Wedeward, Kevin

    will develop and validate a basic model of a permanent magnet DC motor (Yaskawa Electric, Mini-series, Minertia of a permanent magnet DC motor, the field current is constant (i.e. a constant magnetic field). It can be shown(t) = input voltage eb(t) = back emf if(t) = field current (t) = shaft angle (t) = torque J = moment

  15. Inductorless DC-AC Cascaded H-bridge Multilevel Boost Inverter for Electric/Hybrid Electric Vehicle

    E-Print Network [OSTI]

    Tolbert, Leon M.

    Inductorless DC-AC Cascaded H-bridge Multilevel Boost Inverter for Electric/Hybrid Electric Vehicle boost inverter for EV and HEV applications. Currently available power inverter systems for HEVs use a DC- DC boost converter to boost the battery voltage for a traditional 3-phase inverter. The present HEV

  16. Improved DC Gun Insulator

    SciTech Connect (OSTI)

    M.L. Neubauer, K.B. Beard, R. Sah, C. Hernandez-Garcia, G. Neil

    2009-05-01T23:59:59.000Z

    Many user facilities such as synchrotron light sources and free electron lasers require accelerating structures that support electric fields of 10-100 MV/m, especially at the start of the accelerator chain where ceramic insulators are used for very high gradient DC guns. These insulators are difficult to manufacture, require long commissioning times, and have poor reliability, in part because energetic electrons bury themselves in the ceramic, creating a buildup of charge and causing eventual puncture. A novel ceramic manufacturing process is proposed. It will incorporate bulk resistivity in the region where it is needed to bleed off accumulated charge caused by highly energetic electrons. This process will be optimized to provide an appropriate gradient in bulk resistivity from the vacuum side to the air side of the HV standoff ceramic cylinder. A computer model will be used to determine the optimum cylinder dimensions and required resistivity gradient for an example RF gun application. A ceramic material example with resistivity gradient appropriate for use as a DC gun insulator will be fabricated by glazing using doping compounds and tested.

  17. Abstract--Circuit breakers are crucial components for power system operation. The currently adapted time-directed

    E-Print Network [OSTI]

    inspection and preventive maintenance are typically performed. The maintenance schedules and routines usually adapted time-directed maintenance strategy and the emerging new condition-based strategy require has been applied in implementing circuit breaker maintenance and repair tasks. Several potential

  18. Power flow analysis for DC voltage droop controlled DC microgrids

    E-Print Network [OSTI]

    Chaudhary, Sanjay

    loss, such as photovoltaic panels, batteries, fuel cells, LEDs, and electronic loads, DC microgrids sharing and secondary voltage regulation can now be analytically studied, and specialized optimization of the DC microgrid, in term of systematic analysis, protection coordination design, network optimization

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

    DOE Patents [OSTI]

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

    1995-05-23T23:59:59.000Z

    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.

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

    DOE Patents [OSTI]

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

    1995-01-01T23:59:59.000Z

    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.

  1. Catalog of DC Appliances and Power Systems

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01T23:59:59.000Z

    Appliance Efficient DC compatible replacement technology variable-speed compressor and fans run by brushless DC motor in place of single-speed compressors

  2. Exposure information in environmental health research: Current opportunities and future directions for particulate matter, ozone, and toxic air pollutants

    SciTech Connect (OSTI)

    McKone, Thomas E.; Ryan, P. Barry; Ozkaynak, Haluk

    2007-02-01T23:59:59.000Z

    Understanding and quantifying outdoor and indoor sources of human exposure are essential but often not adequately addressed in health-effects studies for air pollution. Air pollution epidemiology, risk assessment, health tracking and accountability assessments are examples of health-effects studies that require but often lack adequate exposure information. Recent advances in exposure modeling along with better information on time-activity and exposure factors data provide us with unique opportunities to improve the assignment of exposures for both future and ongoing studies linking air pollution to health impacts. In September 2006, scientists from the US Environmental Protection Agency (EPA) and the Centers for Disease Control and Prevention (CDC) along with scientists from the academic community and state health departments convened a symposium on air pollution exposure and health in order to identify, evaluate, and improve current approaches for linking air pollution exposures to disease. This manuscript presents the key issues, challenges and recommendations identified by the exposure working group, who used cases studies of particulate matter, ozone, and toxic air pollutant exposure to evaluate health-effects for air pollution. One of the over-arching lessons of this workshop is that obtaining better exposure information for these different health-effects studies requires both goal-setting for what is needed and mapping out the transition pathway from current capabilities to meeting these goals. Meeting our long-term goals requires definition of incremental steps that provide useful information for the interim and move us toward our long-term goals. Another over-arching theme among the three different pollutants and the different health study approaches is the need for integration among alternate exposure assessment approaches. For example, different groups may advocate exposure indicators, biomonitoring, mapping methods (GIS), modeling, environmental media monitoring, and/or personal exposure modeling. However, emerging research reveals that the greatest progress comes from integration among two or more of these efforts.

  3. Recovery Act: Integrated DC-DC Conversion for Energy-Efficient Multicore Processors

    SciTech Connect (OSTI)

    Shepard, Kenneth L

    2013-03-31T23:59:59.000Z

    In this project, we have developed the use of thin-film magnetic materials to improve in energy efficiency of digital computing applications by enabling integrated dc-dc power conversion and management with on-chip power inductors. Integrated voltage regulators also enables fine-grained power management, by providing dynamic scaling of the supply voltage in concert with the clock frequency of synchronous logic to throttle power consumption at periods of low computational demand. The voltage converter generates lower output voltages during periods of low computational performance requirements and higher output voltages during periods of high computational performance requirements. Implementation of integrated power conversion requires high-capacity energy storage devices, which are generally not available in traditional semiconductor processes. We achieve this with integration of thin-film magnetic materials into a conventional complementary metal-oxide-semiconductor (CMOS) process for high-quality on-chip power inductors. This project includes a body of work conducted to develop integrated switch-mode voltage regulators with thin-film magnetic power inductors. Soft-magnetic materials and inductor topologies are selected and optimized, with intent to maximize efficiency and current density of the integrated regulators. A custom integrated circuit (IC) is designed and fabricated in 45-nm CMOS silicon-on-insulator (SOI) to provide the control system and power-train necessary to drive the power inductors, in addition to providing a digital load for the converter. A silicon interposer is designed and fabricated in collaboration with IBM Research to integrate custom power inductors by chip stacking with the 45-nm CMOS integrated circuit, enabling power conversion with current density greater than 10A/mm2. The concepts and designs developed from this work enable significant improvements in performance-per-watt of future microprocessors in servers, desktops, and mobile devices. These new approaches to scaled voltage regulation for computing devices also promise significant impact on electricity consumption in the United States and abroad by improving the efficiency of all computational platforms. In 2006, servers and datacenters in the United States consumed an estimated 61 billion kWh or about 1.5% of the nation's total energy consumption. Federal Government servers and data centers alone accounted for about 10 billion kWh, for a total annual energy cost of about $450 million. Based upon market growth and efficiency trends, estimates place current server and datacenter power consumption at nearly 85 billion kWh in the US and at almost 280 billion kWh worldwide. Similar estimates place national desktop, mobile and portable computing at 80 billion kWh combined. While national electricity utilization for computation amounts to only 4% of current usage, it is growing at a rate of about 10% a year with volume servers representing one of the largest growth segments due to the increasing utilization of cloud-based services. The percentage of power that is consumed by the processor in a server varies but can be as much as 30% of the total power utilization, with an additional 50% associated with heat removal. The approaches considered here should allow energy efficiency gains as high as 30% in processors for all computing platforms, from high-end servers to smart phones, resulting in a direct annual energy savings of almost 15 billion kWh nationally, and 50 billion kWh globally. The work developed here is being commercialized by the start-up venture, Ferric Semiconductor, which has already secured two Phase I SBIR grants to bring these technologies to the marketplace.

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

    SciTech Connect (OSTI)

    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

    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.

  5. A Low-Cost Soft-Switched DC/DC Converter for Solid-Oxide Fuel Cells

    SciTech Connect (OSTI)

    Jason Lai

    2009-03-03T23:59:59.000Z

    A highly efficient DC to DC converter has been developed for low-voltage high-current solid oxide fuel cells. The newly developed 'V6' converter resembles what has been done in internal combustion engine that split into multiple cylinders to increase the output capacity without having to increase individual cell size and to smooth out the torque with interleaving operation. The development was started with topology overview to ensure that all the DC to DC converter circuits were included in the study. Efficiency models for different circuit topologies were established, and computer simulations were performed to determine the best candidate converter circuit. Through design optimization including topology selection, device selection, magnetic component design, thermal design, and digital controller design, a bench prototype rated 5-kW, with 20 to 50V input and 200/400V output was fabricated and tested. Efficiency goal of 97% was proven achievable through hardware experiment. This DC to DC converter was then modified in the later stage to converter 35 to 63 V input and 13.8 V output for automotive charging applications. The complete prototype was tested at Delphi with their solid oxide fuel cell test stand to verify the performance of the modified DC to DC converter. The output was tested up to 3-kW level, and the efficiency exceeded 97.5%. Multiple-phase interleaving operation design was proved to be reliable and ripple free at the output, which is desirable for the battery charging. Overall this is a very successful collaboration project between the SECA Core Technology Team and Industrial Team.

  6. Controlling ultrafast currents by the non-linear photogalvanic effect

    E-Print Network [OSTI]

    Georg Wachter; Shunsuke A. Sato; Christoph Lemell; Xiao-Min Tong; Kazuhiro Yabana; Joachim Burgdörfer

    2015-03-20T23:59:59.000Z

    We theoretically investigate the effect of broken inversion symmetry on the generation and control of ultrafast currents in a transparent dielectric (SiO2) by strong femto-second optical laser pulses. Ab-initio simulations based on time-dependent density functional theory predict ultrafast DC currents that can be viewed as a non-linear photogalvanic effect. Most surprisingly, the direction of the current undergoes a sudden reversal above a critical threshold value of laser intensity I_c ~ 3.8*10^13 W/cm2. We trace this switching to the transition from non-linear polarization currents to the tunneling excitation regime. We demonstrate control of the ultrafast currents by the time delay between two laser pulses. We find the ultrafast current control by the non-linear photogalvanic effect to be remarkably robust and insensitive to laser-pulse shape and carrier-envelope phase.

  7. Switching coordination of distributed dc-dc converters for highly efficient photovoltaic power plants

    DOE Patents [OSTI]

    Agamy, Mohammed; Elasser, Ahmed; Sabate, Juan Antonio; Galbraith, Anthony William; Harfman Todorovic, Maja

    2014-09-09T23:59:59.000Z

    A distributed photovoltaic (PV) power plant includes a plurality of distributed dc-dc converters. The dc-dc converters are configured to switch in coordination with one another such that at least one dc-dc converter transfers power to a common dc-bus based upon the total system power available from one or more corresponding strings of PV modules. Due to the coordinated switching of the dc-dc converters, each dc-dc converter transferring power to the common dc-bus continues to operate within its optimal efficiency range as well as to optimize the maximum power point tracking in order to increase the energy yield of the PV power plant.

  8. High-efficiency solar cells fabricated from direct-current magnetron sputtered n-indium tin oxide onto p-InP grown by atmospheric pressure metalorganic vapor phase epitaxy

    SciTech Connect (OSTI)

    Li, X.; Wanlass, M.W.; Gessert, T.A.; Emery, K.A.; Coutts, T.J.

    1989-05-01T23:59:59.000Z

    Solar cells based on dc magnetron sputtered indium tin oxide onto epitaxially grown films of p-InP have been fabricated and analyzed. The best cells had a global efficiency of 18.4% and an air mass zero (AMO) efficiency of 16.0%. The principal fabrication variable considered was the constituency of the sputtering gas and both argon/hydrogen and argon/oxygen mixtures have been used. The former cells have the higher efficiencies, are apparently stable, and exhibit almost ideal junction characteristics. The latter cells are relatively unstable and exhibit much higher ideality factors and reverse saturation current densities. The temperature dependence of the reverse saturation current indicates totally different charge transfer mechanisms in the two cases.

  9. High efficiency resonant dc/dc converter for solar power applications .

    E-Print Network [OSTI]

    Inam, Wardah

    2013-01-01T23:59:59.000Z

    ??This thesis presents a new topology for a high efficiency dc/dc resonant power converter that utilizes a resistance compression network to provide simultaneous zero voltage… (more)

  10. ReHABit : claiming endangered structures in Washington DC to rethink subsidized housing

    E-Print Network [OSTI]

    Fowlkes, Catherine Kuhnle

    2007-01-01T23:59:59.000Z

    There is an affordable housing crisis today in Washington D.C. that is the result of a uniquely complicated history of a capital city and a current economic boom. This thesis responds to that crisis by proposing a new ...

  11. Effect of energetic electrons on near-wall sheath voltage in the cathode region of a cold cathode direct current discharge

    SciTech Connect (OSTI)

    Blessington, J. [Department of Physics, West Virginia University, Morgantown, West Virginia 26506 (United States); Adams, S. F. [Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433 (United States); Demidov, V. I. [UES, Inc., 4401 Dayton-Xenia Road, Beavercreek, Ohio 45432 (United States); Department of Physics, West Virginia University, Morgantown, West Virginia 26506 (United States); Williamson, J. M. [Innovative Scientific Solutions, Inc., 2766 Indian Ripple Road, Ohio 45440-3638 (United States)

    2009-10-15T23:59:59.000Z

    It is experimentally demonstrated that energetic electrons originating from the cathode or produced in volumetric processes in the cathode region of a cold cathode direct current discharge can create a large potential drop in the near-wall sheath. This voltage drop may be much greater than kT{sub e}/e (where k is the Boltzmann constant, T{sub e} is the electron temperature, and e is the electron charge). Due to the large near-wall sheath voltage, slow and moderately energetic electrons cannot reach the wall and move toward the anode. Application of additional potentials to the wall can change the amount of energetic electrons reaching the wall. This effect can be used for regulation of the near-cathode plasma and near-wall sheath properties and thus may be useful in technical applications.

  12. The smoothing transformer, a new concept in dc side harmonic reduction of HVdc schemes

    SciTech Connect (OSTI)

    Enright, W.; Arrillaga, J.; Wood, A.R.; Hidalgo, F.P.

    1996-10-01T23:59:59.000Z

    Direct connection schemes have been a subject of recent investigation, offering operational flexibility and substantial reductions in ac components. In these schemes the use of active dc filters has been suggested to replace the conventional tuned passive filter design. This paper presents the smoothing transformer as a new means for reducing dc harmonics at characteristic and non-characteristic frequencies using only passive components. A realistic smoothing transformer design is examined using the New Zealand HVdc system operating in the direct connection mode. The steady-state and transient performance of the smoothing transformer design is compared with that of the existing dc smoothing reactor and filter bank.

  13. AC and DC power transmission

    SciTech Connect (OSTI)

    Not Available

    1985-01-01T23:59:59.000Z

    The technical and economic assessment of AC and DC transmission systems; long distance transmission, cable transmission, system inter-connection, voltage support, reactive compensation, stabilisation of systems; parallel operation of DC links with AC systems; comparison between alternatives for particular schemes. Design and application equipment: design, testing and application of equipment for HVDC, series and shunt static compensated AC schemes, including associated controls. Installations: overall design of stations and conductor arrangements for HVDC, series and shunt static AC schemes including insulation co-ordination. System analysis and modelling.

  14. Catalog of DC Appliances and Power Systems

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01T23:59:59.000Z

    DC solar-powered DC air-conditioning heat pump produced byRoom Air Conditioners Geothermal Heat Pumps Lighting-efficiency of an air source electric heat-pump water heater

  15. DC systems with transformerless converters

    SciTech Connect (OSTI)

    Vithayathil, J.J.; Mittlestadt, W. [Bonneville Power Administration, Portland, OR (United States)] [Bonneville Power Administration, Portland, OR (United States); Bjoerklund, P.E. [ABB Power Systems AB, Ludvika (Sweden)] [ABB Power Systems AB, Ludvika (Sweden)

    1995-07-01T23:59:59.000Z

    A technical and economic feasibility study of HVDC systems without converter transformers is presented. The presentation includes proposed solutions to the drawback related to the absence of galvanic separation between the ac and dc systems, if the converter transformers are eliminated. The results show that HVDC systems without converter transformers are both technically and economically feasible. The cost savings can be substantial.

  16. Reliability Assessment of Fault-Tolerant Dc-Dc Converters for Photovoltaic Applications

    E-Print Network [OSTI]

    Liberzon, Daniel

    Reliability Assessment of Fault-Tolerant Dc-Dc Converters for Photovoltaic Applications Sairaj V performance and reliability analysis of switch-mode, dc-dc power converters employed as front ends of the converter's steady-state operation on device failure rates. Markov reliability models are derived to assess

  17. Design and development of a DC-DC converter for a fuel cell inverter system

    E-Print Network [OSTI]

    Gopinath, Rajesh

    2001-01-01T23:59:59.000Z

    This thesis outlines the design and development of a DC-DC converter for a fuel cell inverter application. The proposed DC-DC converter was designed and tested at Texas A&M to meet the specifications laid down for the '2001 Future Energy Challenge...

  18. Dissipative Cryogenic Filters with Zero DC Resistance

    SciTech Connect (OSTI)

    Bluhm, Hendrik; Moler, Kathryn A.; /Stanford U., Appl. Phys. Dept

    2008-04-22T23:59:59.000Z

    The authors designed, implemented and tested cryogenic RF filters with zero DC resistance, based on wires with a superconducting core inside a resistive sheath. The superconducting core allows low frequency currents to pass with negligible dissipation. Signals above the cutoff frequency are dissipated in the resistive part due to their small skin depth. The filters consist of twisted wire pairs shielded with copper tape. Above approximately 1 GHz, the attenuation is exponential in {radical}{omega}, as typical for skin depth based RF filters. By using additional capacitors of 10 nF per line, an attenuation of at least 45 dB above 10 MHz can be obtained. Thus, one single filter stage kept at mixing chamber temperature in a dilution refrigerator is sufficient to attenuate room temperature black body radiation to levels corresponding to 10 mK above about 10 MHz.

  19. DC WRRC Report No. 92 Directory of University Water

    E-Print Network [OSTI]

    District of Columbia, University of the

    DC WRRC Report No. 92 Directory of University Water Expertise in the District of Columbia DC Water Avenue, NW Washington, DC 20008 #12;DC WRRC Report No. 92 Directory of University Water Expertise of Columbia 4200 Connecticut Avenue, NW Washington, DC 20008 #12;DC-WRRC Report No. 92 DIRECTORY OF UNIVERSITY

  20. High energy electron fluxes in dc-augmented capacitively coupled plasmas I. Fundamental characteristics

    SciTech Connect (OSTI)

    Wang Mingmei [Department of Chemical and Biological Engineering, Iowa State University, Ames, Iowa 50010 (United States); Kushner, Mark J. [Department of Electrical Engineering and Computer Science, University of Michigan, 1301 Beal Ave., Ann Arbor, Michigan 48109 (United States)

    2010-01-15T23:59:59.000Z

    Power deposition from electrons in capacitively coupled plasmas (CCPs) has components from stochastic heating, Joule heating, and from the acceleration of secondary electrons through sheaths produced by ion, electron, or photon bombardment of electrodes. The sheath accelerated electrons can produce high energy beams which, in addition to producing excitation and ionization in the gas can penetrate through the plasma and be incident on the opposite electrode. In the use of CCPs for microelectronics fabrication, there may be an advantage to having these high energy electrons interact with the wafer. To control the energy and increase the flux of the high energy electrons, a dc bias can be externally imposed on the electrode opposite the wafer, thereby producing a dc-augmented CCP (dc-CCP). In this paper, the characteristics of dc-CCPs will be discussed using results from a computational study. We found that for a given rf bias power, beams of high energy electrons having a narrow angular spread (<1 deg. ) can be produced incident on the wafer. The maximum energy in the high energy electron flux scales as {epsilon}{sub max}=-V{sub dc}+V{sub rf}+V{sub rf0}, for a voltage on the dc electrode of V{sub dc}, rf voltage of V{sub rf}, and dc bias on the rf electrode of V{sub rf0}. The dc current from the biased electrode must return to ground through surfaces other than the rf electrode and so seeks out a ground plane, typically the side walls. If the side wall is coated with a poorly conducting polymer, the surface will charge to drive the dc current through.

  1. Low Cost, High Temperature, High Ripple Current DC Bus Capacitors |

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-UpHeatMulti-Dimensionalthe10IO1OP001Long-Term Storage ofEnergy HighCost, Durable

  2. Graphite electrode DC arc furnace. Innovative technology summary report

    SciTech Connect (OSTI)

    NONE

    1999-05-01T23:59:59.000Z

    The Graphite Electrode DC Arc Furnace (DC Arc) is a high-temperature thermal process, which has been adapted from a commercial technology, for the treatment of mixed waste. A DC Arc Furnace heats waste to a temperature such that the waste is converted into a molten form that cools into a stable glassy and/or crystalline waste form. Hazardous organics are destroyed through combustion or pyrolysis during the process and the majority of the hazardous metals and radioactive components are incorporated in the molten phase. The DC Arc Furnace chamber temperature is approximately 593--704 C and melt temperatures are as high as 1,500 C. The DC Arc system has an air pollution control system (APCS) to remove particulate and volatiles from the offgas. The advantage of the DC Arc is that it is a single, high-temperature thermal process that minimizes the need for multiple treatment systems and for extensive sorting/segregating of large volumes of waste. The DC Arc has the potential to treat a wide range of wastes, minimize the need for sorting, reduce the final waste volumes, produce a leach resistant waste form, and destroy organic contaminants. Although the DC arc plasma furnace exhibits great promise for treating the types of mixed waste that are commonly present at many DOE sites, several data and technology deficiencies were identified by the Mixed Waste Focus Area (MWFA) regarding this thermal waste processing technique. The technology deficiencies that have been addressed by the current studies include: establishing the partitioning behavior of radionuclides, surrogates, and hazardous metals among the product streams (metal, slag, and offgas) as a function of operating parameters, including melt temperature, plenum atmosphere, organic loading, chloride concentration, and particle size; demonstrating the efficacy of waste product removal systems for slag and metal phases; determining component durability through test runs of extended duration, evaluating the effect of feed composition variations on process operating conditions and slag product performance; and collecting mass balance and operating data to support equipment and instrument design.

  3. Disc rotors with permanent magnets for brushless dc motor

    SciTech Connect (OSTI)

    Hawsey, R.A.; Bailery, J.M.

    1992-05-26T23:59:59.000Z

    This patent describes a brushless dc permanent magnet motor for driving an autonomous underwater vehicle. It comprises first and second substantially flat, generally cylindrical stators disposed in side by side relation; a first substantially flat, generally cylindrical rotor; a first shaft connected to the first rotor and a second, concentric shaft connected to the second rotor; and means for providing rotation of the first and second shafts in opposite directions.

  4. Basic DC Meter Design ECE 2100 Circuit Analysis Laboratory

    E-Print Network [OSTI]

    Miller, Damon A.

    Basic DC Meter Design ECE 2100 Circuit Analysis Laboratory updated 8 January 2008 Pre-Laboratory Assignment 1. Design an ammeter with full scale current IFS equal to 5 mA using a meter movement rated at 0.5 mA and 100 mV. 2. Design a voltmeter with a full scale voltage VFS equal to 10 V using the meter

  5. Pyroelectric response mechanism of barium strontium titanate ceramics in dielectric bolometer mode: The underlying essence of the enhancing effect of direct current bias field

    SciTech Connect (OSTI)

    Mao, Chaoliang; Cao, Sheng; Yan, Shiguang; Yao, Chunhua; Cao, Fei; Wang, Genshui; Dong, Xianlin [Key Laboratory of Inorganic Functional Materials and Devices, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 1295 Dingxi Road, Changning, Shanghai 200050 (China)] [Key Laboratory of Inorganic Functional Materials and Devices, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 1295 Dingxi Road, Changning, Shanghai 200050 (China); Hu, Xu; Yang, Chunli [Kunming Institute of Physics, Kunming 650223 (China)] [Kunming Institute of Physics, Kunming 650223 (China)

    2013-06-17T23:59:59.000Z

    Pyroelectric response mechanism of Ba{sub 0.70}Sr{sub 0.30}TiO{sub 3} ceramics under dielectric bolometer (DB) mode was investigated by dielectric and pyroelectric properties measurement. The variations of total, intrinsic, and induced pyroelectric coefficients (p{sub tot}, p{sub int}, p{sub ind}) with temperatures and bias fields were analyzed. p{sub int} plays the dominant role to p{sub tot} through most of the temperature range and p{sub ind} will be slightly higher than p{sub int} above T{sub 0}. The essence of the enhancing effect of DC bias field on pyroelectric coefficient can be attributed to the high value of p{sub int}. This mechanism is useful for the pyroelectric materials (DB mode) applications.

  6. Ion mass spectrometry investigations of the discharge during reactive high power pulsed and direct current magnetron sputtering of carbon in Ar and Ar/N{sub 2}

    SciTech Connect (OSTI)

    Schmidt, S.; Greczynski, G.; Jensen, J.; Hultman, L. [Thin Film Physics Div., Department of Physics (IFM), Linkoeping University, SE-581 83 (Sweden); Czigany, Zs. [Institute of Technical Physics and Materials Science, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Konkoly Thege Miklos ut 29-33. H-1121 Budapest (Hungary)

    2012-07-01T23:59:59.000Z

    Ion mass spectrometry was used to investigate discharges formed during high power impulse magnetron sputtering (HiPIMS) and direct current magnetron sputtering (DCMS) of a graphite target in Ar and Ar/N{sub 2} ambient. Ion energy distribution functions (IEDFs) were recorded in time-averaged and time-resolved mode for Ar{sup +}, C{sup +}, N{sub 2}{sup +}, N{sup +}, and C{sub x}N{sub y}{sup +} ions. An increase of N{sub 2} in the sputter gas (keeping the deposition pressure, pulse width, pulse frequency, and pulse energy constant) results for the HiPIMS discharge in a significant increase in C{sup +}, N{sup +}, and CN{sup +} ion energies. Ar{sup +}, N{sub 2}{sup +}, and C{sub 2}N{sup +} ion energies, in turn, did not considerably vary with the changes in working gas composition. The HiPIMS process showed higher ion energies and fluxes, particularly for C{sup +} ions, compared to DCMS. The time evolution of the plasma species was analyzed for HiPIMS and revealed the sequential arrival of working gas ions, ions ejected from the target, and later during the pulse-on time molecular ions, in particular CN{sup +} and C{sub 2}N{sup +}. The formation of fullerene-like structured CN{sub x} thin films for both modes of magnetron sputtering is explained by ion mass-spectrometry results and demonstrated by transmission electron microscopy as well as diffraction.

  7. 45nm direct battery DC-DC converter for mobile applications

    E-Print Network [OSTI]

    Bandyopadhyay, Saurav

    2010-01-01T23:59:59.000Z

    Portable devices use Lithium-ion batteries as the energy source due to their high energy density, long cycle life and low memory effects. With the aggressive downscaling of CMOS, it is becoming increasingly difficult to ...

  8. Active dc filter for HVDC systems

    SciTech Connect (OSTI)

    Zhang, W. (Royal Inst. of Tech., Stockholm (Sweden)); Asplund, G.

    1994-01-01T23:59:59.000Z

    This article is a case history of the installation of active dc filters for high-performance, low-cost harmonics filtering at the Lindome converter station in the Konti-Skan 2 HVDC transmission link between Denmark and Sweden. The topics of the article include harmonics, interference, and filters, Lindome active dc filter, active dc filter design, digital signal processor, control scheme, protection and fault monitoring, and future applications.

  9. New Architectures for Radio-Frequency DC-DC Power Conversion

    E-Print Network [OSTI]

    Rivas, Juan M.

    This document proposes two new architectures for switched-mode dc–dc power conversion. The proposed architectures enable dramatic increases in switching frequency to be realized while preserving features critical in practice, ...

  10. DC to DC power conversion module for the all-electric ship

    E-Print Network [OSTI]

    Gray, Weston L

    2011-01-01T23:59:59.000Z

    The MIT end to end electric ship model is being developed to study competing electric ship designs. This project produced a model of a Power Conversion Module (PCM)- 4, DC-to-DC converter which interfaces with the MIT ...

  11. Computer-aided optimization of DC/DC converters for automotive applications

    E-Print Network [OSTI]

    Neugebauer, Timothy C.

    This paper investigates computer-aided optimization of DC/DC converters, with a focus on converters for dual-voltage automotive electrical systems. A new CAD optimization approach based on Monte Carlo search methods is ...

  12. Program stat3d.c /* Program: stat3d.c */

    E-Print Network [OSTI]

    Bentz, Dale P.

    85 Program stat3d.c /************************************************************************/ /* */ /* Program: stat3d.c */ /* Purpose: To read in a 3-D image and output phase volumes */ /* and report("Phase Volume Surface Volume Surface \

  13. Analysis of a transformer-less, multi-level DC-DC converter for HVDC operation

    SciTech Connect (OSTI)

    Karady, G.G.; Devarajan, S. [Arizona State Univ., Tempe, AZ (United States)

    1998-12-31T23:59:59.000Z

    HVDC systems require DC step up and DC step down units. The traditional approach is the application of twelve-pulse thyristor bridges with transformers. The developments of fast switching IGBT devices permit the development of transformer-less, multi-level converters. A multi-level circuit was suggested by Limpaecher. This paper presents a detailed simulation of the proposed circuit together with the analysis of its performance. The converter consists of a set of capacitors, air core inductors and solid state switches arranged in a ladder network. In the step-up mode, the closing of solid state switches resonantly charges the capacitors in parallel through an air-cored inductor. Then solid state switches resonantly charges the capacitors in parallel through an air-cored inductor. Then solid state switches connect the capacitors in series and discharge them through an air-core inductor to the load. In the step-down mode the capacitors are charged in series and discharged in parallel. The circuit has three modes of operation in each cycle: charge, inversion, and discharge. The circuit operation is analyzed in each mode using SPICE simulations. The selection of the components is discussed and output voltage regulation is analyzed. The results show that the proposed circuit promises significant reduction of losses, because of the zero current switching. The investment cost is reduced because of the elimination of transformers.

  14. Catalog of DC Appliances and Power Systems

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01T23:59:59.000Z

    48V DC , depending on battery bank configuration. Lifetime:Characteristics: Lead-acid battery banks are composed ofto produce the desired battery bank voltage. Typical battery

  15. 26 Tesla DC Magnet for Neutron Scattering

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

    Previously, DC Magnets located at Neutron-Scattering Beamlines were commercially-manufactured superconducting magnets and limited to 17 T. A few pulsed magnet systems have been...

  16. Fault current limiter

    DOE Patents [OSTI]

    Darmann, Francis Anthony

    2013-10-08T23:59:59.000Z

    A fault current limiter (FCL) includes a series of high permeability posts for collectively define a core for the FCL. A DC coil, for the purposes of saturating a portion of the high permeability posts, surrounds the complete structure outside of an enclosure in the form of a vessel. The vessel contains a dielectric insulation medium. AC coils, for transporting AC current, are wound on insulating formers and electrically interconnected to each other in a manner such that the senses of the magnetic field produced by each AC coil in the corresponding high permeability core are opposing. There are insulation barriers between phases to improve dielectric withstand properties of the dielectric medium.

  17. Extended Constant Power Speed Range of the Brushless DC Motor Through Dual Mode Inverter Control

    SciTech Connect (OSTI)

    Lawler, J.S.

    2000-06-23T23:59:59.000Z

    The trapezoidal back electromotive force (emf) brushless direct current (dc) motor (BDCM) with surface-mounted magnets has high-power density and efficiency especially when rare-earth magnet materials are used. Traction applications, such as electric vehicles, could benefit significantly from the use of such motors. Unfortunately, a practical means for driving the motor over a constant power speed ratio (CPSR) of 5:1 or more has not yet been developed. A key feature of these motors is that they have low internal inductance. The phase advance method is effective in controlling the motor power over such a speed range, but the current at high speed may be several times greater than that required at the base speed. The increase in current during high-speed operation is due to the low motor inductance and the action of the bypass diodes of the inverter. The use of such a control would require increased current rating of the inverter semiconductors and additional cooling for the inverter, where the conduction losses increase proportionally with current, and especially for the motor, where the losses increase with the square of the current. The high current problems of phase advance can be mitigated by adding series inductance; however, this reduces power density, requires significant increase in supply voltage, and leaves the CPSR performance of the system highly sensitive to variations in the available voltage. A new inverter topology and control scheme has been developed that can drive low-inductance BDCMs over the CPSR that would be required in electric vehicle applications. This new controller is called the dual-mode inverter control (DMIC). It is shown that the BDCM has an infinite CPSR when it is driven by the DMIC.

  18. Quantitative study of macroscopic quantum tunneling in a dc SQUID: A system with two degrees of freedom

    E-Print Network [OSTI]

    Li, Shaoxiong; Yu, Yang; Zhang, Y.; Qiu, W.; Han, Siyuan; Wang, Z.

    2002-08-01T23:59:59.000Z

    To test whether the theory of macroscopic quantum tunneling (MQT) is applicable to systems with 2 degrees of freedom, we experimentally investigated the switching current distribution of a dc SQUID. Using sample parameters determined from...

  19. Thermal stability of Al- and Zr-doped HfO{sub 2} thin films grown by direct current magnetron sputtering

    SciTech Connect (OSTI)

    Hong, Yeong-Eui; Kim, Yong-Seok; Do, Kihoon; Lee, Dongwon; Ko, Dae-Hong; Ku, Ja-Hum; Kim, Hyoungsub [Department of Ceramic Engineering, Yonsei University, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-749 (Korea, Republic of); Semiconductor R and D Division, Samsung Electronics Co, Ltd., San no. 24, Nongseo-Ri, Kiheung-Eup, Yongin-City, Kyunggi-Do 449-711 (Korea, Republic of); Department of Advanced Materials Engineering, Sungkyunkwan University, 300 Chunchun-Dong, Jangan-Ku, Suwon 440-746 (Korea, Republic of)

    2005-09-15T23:59:59.000Z

    Ultrathin HfO{sub 2} dielectric films doped with Al and Zr were grown on p-type Si(100) substrates by dc magnetron sputtering, and their microstructural and electrical properties were examined. Compositions and chemical states of the dielectric films were analyzed by Rutherford backscattering spectrometry and x-ray photoelectron spectroscopy. The HfO{sub 2} films doped with Zr were crystallized even from the as-deposited state, however, the crystallization temperature of the HfO{sub 2} film doped with 16% Al{sub 2}O{sub 3} was delayed up to 900 deg. C. As the annealing temperature increases, high-resolution transmission electron microscopy analyses of all doped HfO{sub 2} films showed an increase of the interfacial layer thickness due to the diffusion of small partial pressure of oxygen in annealing ambient. Our results also showed that the addition of Al{sub 2}O{sub 3} to 14% is not useful for blocking the oxygen diffusion through the (HfO{sub 2}){sub 0.86}(Al{sub 2}O{sub 3}){sub 0.14} film. From the capacitance-voltage measurements, the dielectric constants of the Al- and Zr-doped HfO{sub 2} thin films were measured to be 18.7 and 7.6, respectively.

  20. High Gain Transformerless DC-DC Converters for Renewable Energy Sources

    E-Print Network [OSTI]

    Denniston, Nicholas Aaron

    2011-08-08T23:59:59.000Z

    mode DCM Discontinuous conduction mode EAR Equivalent averaged resistance ESR Equivalent series resistance FC Fuel cell fS Switching frequency HVDC High voltage direct current ix, vx Instantaneous current, voltage of node x Ix, Vx Average....1. Introduction ................................................................................... 59 5.2. Design example and simulation .................................................... 62 5.3. Evaluation of multiple module approach in HVDC converters...

  1. DC-based magnetic field controller

    DOE Patents [OSTI]

    Kotter, Dale K. (Shelley, ID); Rankin, Richard A. (Ammon, ID); Morgan, John P,. (Idaho Falls, ID)

    1994-01-01T23:59:59.000Z

    A magnetic field controller for laboratory devices and in particular to dc operated magnetic field controllers for mass spectrometers, comprising a dc power supply in combination with improvements to a hall probe subsystem, display subsystem, preamplifier, field control subsystem, and an output stage.

  2. DC-based magnetic field controller

    DOE Patents [OSTI]

    Kotter, D.K.; Rankin, R.A.; Morgan, J.P.

    1994-05-31T23:59:59.000Z

    A magnetic field controller is described for laboratory devices and in particular to dc operated magnetic field controllers for mass spectrometers, comprising a dc power supply in combination with improvements to a Hall probe subsystem, display subsystem, preamplifier, field control subsystem, and an output stage. 1 fig.

  3. Multilevel-Dc-Bus Inverter For Providing Sinusoidal And Pwm Electrical Machine Voltages

    DOE Patents [OSTI]

    Su, Gui-Jia [Knoxville, TN

    2005-11-29T23:59:59.000Z

    A circuit for controlling an ac machine comprises a full bridge network of commutation switches which are connected to supply current for a corresponding voltage phase to the stator windings, a plurality of diodes, each in parallel connection to a respective one of the commutation switches, a plurality of dc source connections providing a multi-level dc bus for the full bridge network of commutation switches to produce sinusoidal voltages or PWM signals, and a controller connected for control of said dc source connections and said full bridge network of commutation switches to output substantially sinusoidal voltages to the stator windings. With the invention, the number of semiconductor switches is reduced to m+3 for a multi-level dc bus having m levels. A method of machine control is also disclosed.

  4. Aternating current photovoltaic building block

    DOE Patents [OSTI]

    Bower, Ward Issac; Thomas, Michael G.; Ruby, Douglas S.

    2004-06-15T23:59:59.000Z

    A modular apparatus for and method of alternating current photovoltaic power generation comprising via a photovoltaic module, generating power in the form of direct current; and converting direct current to alternating current and exporting power via one or more power conversion and transfer units attached to the module, each unit comprising a unitary housing extending a length or width of the module, which housing comprises: contact means for receiving direct current from the module; one or more direct current-to-alternating current inverters; an alternating current bus; and contact means for receiving alternating current from the one or more inverters.

  5. Counterrotating brushless dc permanent magnet motor

    SciTech Connect (OSTI)

    Hawsey, R.A.; Bailey, J.M.

    1990-12-31T23:59:59.000Z

    An brushless DC permanent magnet motor is provided for driving an autonomous underwater vehicle. In one embodiment, the motor comprises four substantially flat stators disposed in stacked relationship, with pairs of the stators being axially spaced and each of the stators comprising a tape-wound stator coil; and a first and second substantially flat rotors disposed between the spaced pairs of stators. Each of the rotors includes an annular array of permanent magnets embedded therein. A first shaft is connected to the first rotor and a second, concentric shaft is connected to the second rotor, and drive unit causes rotation of the two shafts in opposite directions. The second shaft comprises a hollow tube having a central bore therein in which the first shaft is disposed. Two different sets of bearings support the first and second shAfts. In another embodiment, the motor comprises two ironless stators and pairs and rotors mounted no opposite sides of the stators and driven by counterrotating shafts.

  6. Counterrotating brushless dc permanent magnet motor

    SciTech Connect (OSTI)

    Hawsey, R.A.; Bailey, J.M.

    1990-01-01T23:59:59.000Z

    An brushless DC permanent magnet motor is provided for driving an autonomous underwater vehicle. In one embodiment, the motor comprises four substantially flat stators disposed in stacked relationship, with pairs of the stators being axially spaced and each of the stators comprising a tape-wound stator coil; and a first and second substantially flat rotors disposed between the spaced pairs of stators. Each of the rotors includes an annular array of permanent magnets embedded therein. A first shaft is connected to the first rotor and a second, concentric shaft is connected to the second rotor, and drive unit causes rotation of the two shafts in opposite directions. The second shaft comprises a hollow tube having a central bore therein in which the first shaft is disposed. Two different sets of bearings support the first and second shAfts. In another embodiment, the motor comprises two ironless stators and pairs and rotors mounted no opposite sides of the stators and driven by counterrotating shafts.

  7. DC Microgrids Scoping Study: Estimate of Technical and Economic...

    Energy Savers [EERE]

    manufacturers, power system designers, and researchers are demonstrating and deploying DC power distribution systems for applications where the end-use loads are natively DC, e.g.,...

  8. INL Efficiency and Security Testing of EVSE, DC Fast Chargers...

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

    INL Efficiency and Security Testing of EVSE, DC Fast Chargers, and Wireless Charging Systems INL Efficiency and Security Testing of EVSE, DC Fast Chargers, and Wireless Charging...

  9. ADAPTIVE HYSTERESIS CURRENT CONTROL OF INVERTER FOR SOLAR PHOTOVOLTAIC APPLICATIONS

    E-Print Network [OSTI]

    unknown authors

    2011-01-01T23:59:59.000Z

    Abstract – Power inverters are used to convert the D.C power produced by the solar photovoltaic cell into AC. This paper presents a novel Adaptive Hysteresis Current Controller to control the inverter, used in the solar photovoltaic cell. The proposed controller is capable of reducing the total harmonic distortion and to provide constant switching frequency. The mathematical model of Photovoltaic array is developed using the Newton’s method using the parameter obtained from a commercial photovoltaic data sheet under variable weather conditions, in which the effect of irradiance and temperature are considered. The modeled Photovoltaic array is interfaced with DC-DC boost converter, AC-DC inverter and load. A DC-DC boost converter is used to step up the input DC voltage of the Photovoltaic array while the DC-AC single-phase inverter converts the input DC comes from boost converter into AC. The performance of the proposed controller of inverter is evaluated through MATLAB-Simulation. The results obtained with the proposed algorithm are compared with those obtained when using conventional fixed hysteresis current controller for single-phase photovoltaic inverter in terms of THD and switching frequency.

  10. Current measurement apparatus

    DOE Patents [OSTI]

    Umans, Stephen D. (Belmont, MA)

    2008-11-11T23:59:59.000Z

    Apparatus and methods are provided for a system for measurement of a current in a conductor such that the conductor current may be momentarily directed to a current measurement element in order to maintain proper current without significantly increasing an amount of power dissipation attributable to the current measurement element or adding resistance to assist in current measurement. The apparatus and methods described herein are useful in superconducting circuits where it is necessary to monitor current carried by the superconducting elements while minimizing the effects of power dissipation attributable to the current measurement element.

  11. National Aeronautics and Space Administration Washington, DC

    E-Print Network [OSTI]

    Rathbun, Julie A.

    National Aeronautics and Space Administration Washington, DC NASA ADVISORY COUNCIL PLANETARY, including Discovery @15 and Satellites of the Outer Solar System. The next workshop, Planetary Atmospheres (GRAIL)--a lunar mission, Origins Spectral Interpretation, Resource Identification, and Security (OSIRIS

  12. DC readout experiment in Enhanced LIGO

    E-Print Network [OSTI]

    Fricke, Tobin T

    The two 4 km long gravitational wave detectors operated by the Laser Interferometer Gravitational-wave Observatory (LIGO) were modified in 2008 to read out the gravitational wave channel using the DC readout form of homodyne ...

  13. Modeling and Optimization of Direct Chill Casting to Reduce Ingot Cracking

    SciTech Connect (OSTI)

    Das, Subodh K.

    2006-01-09T23:59:59.000Z

    A successful four-year project on the modeling and optimization of direct chill (DC) casting to reduce ingot cracking has been completed. The project involved close collaboration among private industries, national laboratories, and universities. During the four-year project, 16 quarterly meetings brought the industrial partners and the research team together for discussion of research results and research direction. The industrial partners provided guidance, facilities, and experience to the research team. The research team went to two industrial plants to measure temperature distributions in commercial 60,000-lb DC casting ingot. The collaborative research resulted in several major accomplishments or findings: (1) Surface cracks were shown to be a result of hot tearing rather than cold cracks, as was thought before this project. These cracks form on the surface of a DC cast ingot just above the impingement point of the secondary cooling water jets. The cracks form along dendrite and grain boundaries, where solute and impurity elements are highly segregated. This understanding led to the development of a new technique for determining the mechanical properties in the nonequilibrium mushy zone of alloys and to thermodynamic predictions of the hot tearing propensity of DC cast ingots. (2) The apparent heat transfer coefficient (HTC) at the ingot surface in the water cooling region during DC casting was determined on the basis of temperature measurements in commercial DC casting ingots and an inverse heat transfer analysis. HTCs were calculated as a function of temperature and time, and covered the different regimes of heat transfer expected during DC casting. The calculated values were extrapolated to include the effect of water flow rate. The calculated HTCs had a peak at around 200 C, corresponding to the high heat transfer rates during nucleate boiling, and the profile was consistent with similar data published in the literature. (3) A new method, termed the reheating-cooling method (RCM), was developed and validated for measuring mechanical properties in the nonequilibrium mushy zones of alloys. The new method captures the brittle nature of aluminum alloys at temperatures close to the nonequilibrium solidus temperature, while specimens tested using the reheating method exhibit significant ductility. The RCM has been used for determining the mechanical properties of alloys at nonequilibrium mushy zone temperatures. Accurate data obtained during this project show that the metal becomes more brittle at high temperatures and high strain rates. (4) The elevated-temperature mechanical properties of the alloy were determined. Constitutive models relating the stress and strain relationship at elevated temperatures were also developed. The experimental data fit the model well. (5) An integrated 3D DC casting model has been used to simulate heat transfer, fluid flow, solidification, and thermally induced stress-strain during casting. A temperature-dependent HTC between the cooling water and the ingot surface, cooling water flow rate, and air gap were coupled in this model. An elasto-viscoplastic model based on high-temperature mechanical testing was used to calculate the stress during casting. The 3D integrated model can be used for the prediction of temperature, fluid flow, stress, and strain distribution in DC cast ingots. (6) The cracking propensity of DC cast ingots can be predicted using the 3D integrated model as well as thermodynamic models. Thus, an ingot cracking index based on the ratio of local stress to local alloy strength was established. Simulation results indicate that cracking propensity increases with increasing casting speed. The composition of the ingots also has a major effect on cracking formation. It was found that copper and zinc increase the cracking propensity of DC cast ingots. The goal of this Aluminum Industry of the Future (IOF) project was to assist the aluminum industry in reducing the incidence of stress cracks in DC castings from a current level of 5% down to 2%. This could lead to energy savings

  14. Hydrogen Storage Systems Analysis Working Group Meeting Argonne DC Offices

    E-Print Network [OSTI]

    Hydrogen Storage Systems Analysis Working Group Meeting Argonne DC Offices L'Enfant Plaza, Washington, DC December 4, 2007 SUMMARY REPORT Compiled by Romesh Kumar Argonne National Laboratory Working Group Meeting December 4, 2007 Argonne DC Offices, L'Enfant Plaza, Washington, DC Meeting

  15. DC WRRC Report No. 142 Directory of University Water Expertise

    E-Print Network [OSTI]

    District of Columbia, University of the

    DC WRRC Report No. 142 Directory of University Water Expertise in the District of Columbia r DC.B. 5004 Washington, D.C. 20008 #12;DC WRRC Report No. 142 Directory of University Water Expertise ............ 26 FACULTY INDEX .......................................... 29 DIRECTORY UPDATE FORM

  16. Electron-deformation mechanism of photoexcitation of hypersound in semiconductors in a dc electric field

    SciTech Connect (OSTI)

    Chigarev, N V [International Laser Center, M. V. Lomonosov Moscow State University, Moscow (Russian Federation)

    2002-09-30T23:59:59.000Z

    The effect of a dc electric field on photoexcitation of a hypersonic pulse in a semiconductor via an electron-deformation mechanism is studied. The profiles of acoustic pulses are simulated for different directions of the electric field. (laser applications and other topics in quantum electronics)

  17. Understanding S-shaped current-voltage characteristics of organic solar cells: Direct measurement of potential distributions by scanning Kelvin probe

    SciTech Connect (OSTI)

    Saive, Rebecca, E-mail: rebecca.saive@innovationlab.de; Kowalsky, Wolfgang [InnovationLab GmbH, 69115 Heidelberg (Germany) [InnovationLab GmbH, 69115 Heidelberg (Germany); Institut für Hochfrequenztechnik, TU Braunschweig, 38106 Braunschweig (Germany); Kirchhoff-Institute for Physics, Heidelberg University, 69120 Heidelberg (Germany); Mueller, Christian [InnovationLab GmbH, 69115 Heidelberg (Germany) [InnovationLab GmbH, 69115 Heidelberg (Germany); Kirchhoff-Institute for Physics, Heidelberg University, 69120 Heidelberg (Germany); Schinke, Janusz; Lovrincic, Robert [InnovationLab GmbH, 69115 Heidelberg (Germany) [InnovationLab GmbH, 69115 Heidelberg (Germany); Institut für Hochfrequenztechnik, TU Braunschweig, 38106 Braunschweig (Germany)

    2013-12-09T23:59:59.000Z

    We present a comparison of the potential distribution along the cross section of bilayer poly(3-hexylthiophene)/1-(3-methoxycarbonyl)propyl-1-phenyl[6,6]C61 (P3HT/PCBM) solar cells, which show normal and anomalous, S-shaped current-voltage (IV) characteristics. We expose the cross sections of the devices with a focussed ion beam and measure them with scanning Kelvin probe microscopy. We find that in the case of S-shaped IV-characteristics, there is a huge potential drop at the PCBM/Al top contact, which does not occur in solar cells with normal IV-characteristics. This behavior confirms the assumption that S-shaped curves are caused by hindered charge transport at interfaces.

  18. Rotary Electrodynamics of a DC Motor: Motor as Mechanical Capacitor Lab 2: Modeling and System Identification

    E-Print Network [OSTI]

    ). · im is the current through the motor. Because the motor is in series with all other electrical). Because power is conserved, m = Kmim (motor efficiency is actually closer to 69%). Here, Km 0.00767 VRotary Electrodynamics of a DC Motor: Motor as Mechanical Capacitor Lab 2: Modeling and System

  19. Electrical detection of spin pumping: dc voltage generated by ferromagnetic resonance at ferromagnet/nonmagnet contact

    E-Print Network [OSTI]

    van der Wal, Caspar H.

    Electrical detection of spin pumping: dc voltage generated by ferromagnetic resonance We describe electrical detection of spin pumping in metallic nanostructures. In the spin pumping effect, a precessing ferromagnet attached to a normal metal acts as a pump of spin-polarized current

  20. Control of a Fuel-Cell Powered DC Electric Vehicle Motor Federico Zenith

    E-Print Network [OSTI]

    Skogestad, Sigurd

    Control of a Fuel-Cell Powered DC Electric Vehicle Motor Federico Zenith Sigurd Skogestad Introduction Research in fuel cells receives currently a lot of interest. Fuel cells can be used, in different. However, the dynamics of fuel cells has received comparatively less attention. Control of fuel cells

  1. High Precision Load Current Sensing using On-Line Calibration of Trace Resistance

    E-Print Network [OSTI]

    Sanders, Seth

    -line specification. This and high-bandwidth measurement of the load current in the allows the converter to follow pose unprecedented demands on DC-DC power converters, it could be very difficult to follow the loadHigh Precision Load Current Sensing using On-Line Calibration of Trace Resistance in VRM

  2. Electric Currents Electric Current

    E-Print Network [OSTI]

    Yu, Jaehoon

    ;Problem 3: At $0.095/kWh, what does it cost to leave a 25W porch light on day and night for a year = 219000 Watt- hour = 219kWh. So, total cost = 219 x$0.095 = $20.8 #12;Problem 4: A 100 W light bulb has of charge per unit time: = . Unit of current: Ampere (A). The purpose of a battery is to produce

  3. A Novel Current Angle Control Scheme in a Current Source Inverter Fed Permanent Magnet Synchronous Motor Drive for Automotive Applications

    SciTech Connect (OSTI)

    Tang, Lixin [ORNL] [ORNL; Su, Gui-Jia [ORNL] [ORNL

    2011-01-01T23:59:59.000Z

    This paper describes a novel speed control scheme to operate a current source inverter (CSI) driven surface-mounted permanent magnet synchronous machine (SPMSM) for hybrid electric vehicles (HEVs) applications. The idea is to use the angle of the current vector to regulate the rotor speed while keeping the two dc-dc converter power switches on all the time to boost system efficiency. The effectiveness of the proposed scheme was verified with a 3 kW CSI-SPMSM drive prototype.

  4. New Experimental Data in DC745U

    SciTech Connect (OSTI)

    Ortiz-Acosta, Denisse [Los Alamos National Laboratory; Cady, Carl [Los Alamos National Laboratory; Densmore, Crystal [Los Alamos National Laboratory

    2012-06-18T23:59:59.000Z

    The objectives of this project are: (1) study the molecular and mechanical properties of DC745U - (a) DC745U is a silicone elastomer used in several weapons systems, (b) depending on their chemistry and formulation, polymers can be susceptible to damage and failures due to weak chemical linkages and physical interactions, (c) inefficient production processes can generate heterogeneities throughout the material that can contribute negatively to the overall performance and lifetime of the polyer, (d) aging, long-term thermal and radioactive conditions, and mechanical strains can affect the materials network structure and contribute to the degradation of the production; (2) characterization of DC745U materials cured under different conditions to determine possible differences to the polymer structure; and (3) this work is relevant to mission-critical programs and for supporting programmatic work for weapon research.

  5. Ionization tube simmer current circuit

    DOE Patents [OSTI]

    Steinkraus, Jr., Robert F. (Livermore, CA)

    1994-01-01T23:59:59.000Z

    A highly efficient flash lamp simmer current circuit utilizes a fifty percent duty cycle square wave pulse generator to pass a current over a current limiting inductor to a full wave rectifier. The DC output of the rectifier is then passed over a voltage smoothing capacitor through a reverse current blocking diode to a flash lamp tube to sustain ionization in the tube between discharges via a small simmer current. An alternate embodiment of the circuit combines the pulse generator and inductor in the form of an FET off line square wave generator with an impedance limited step up output transformer which is then applied to the full wave rectifier as before to yield a similar simmer current.

  6. Ionization tube simmer current circuit

    DOE Patents [OSTI]

    Steinkraus, R.F. Jr.

    1994-12-13T23:59:59.000Z

    A highly efficient flash lamp simmer current circuit utilizes a fifty percent duty cycle square wave pulse generator to pass a current over a current limiting inductor to a full wave rectifier. The DC output of the rectifier is then passed over a voltage smoothing capacitor through a reverse current blocking diode to a flash lamp tube to sustain ionization in the tube between discharges via a small simmer current. An alternate embodiment of the circuit combines the pulse generator and inductor in the form of an FET off line square wave generator with an impedance limited step up output transformer which is then applied to the full wave rectifier as before to yield a similar simmer current. 6 figures.

  7. Development of 500 kV DC PPLP-insulated oil-filled submarine cable

    SciTech Connect (OSTI)

    Fujimori, A. [Kansai Electric Power Co., Inc., Osaka (Japan)] [Kansai Electric Power Co., Inc., Osaka (Japan); Tanaka, T. [Electric Power Development Co., Ltd., Tokyo (Japan)] [Electric Power Development Co., Ltd., Tokyo (Japan); Takashima, H. [Shikoku Electric Power Co., Inc., Kagawa (Japan)] [Shikoku Electric Power Co., Inc., Kagawa (Japan); Imajo, T. [Central Research Inst. of Electric Power Industry, Tokyo (Japan)] [Central Research Inst. of Electric Power Industry, Tokyo (Japan); Hata, R. [Sumitomo Electric Industries, Ltd., Osaka (Japan)] [Sumitomo Electric Industries, Ltd., Osaka (Japan); Tanabe, T. [Furukawa Electric Co., Ltd., Tokyo (Japan)] [Furukawa Electric Co., Ltd., Tokyo (Japan); Yoshida, S. [Fujikura, Ltd., Tokyo (Japan)] [Fujikura, Ltd., Tokyo (Japan); Kakihana, T. [Hitachi Cable, Ltd., Tokyo (Japan)] [Hitachi Cable, Ltd., Tokyo (Japan)

    1996-01-01T23:59:59.000Z

    This paper outlines the development of a 500 kV DC oil-filled submarine cable capable of transmitting 2,800 MW with {+-} 500 kV 2800A bipole system. Polypropylene Laminated Paper (PPL) was employed as the insulation material, which is the worlds first application to DC cables. The conductor size is 3,000 mm{sup 2}, which is the largest size for submarine cables ever put into practical use. Through various fundamental and prototype tests, the cable proved to have excellent electrical characteristics for DC voltage as well as transient overvoltage. The cable and accessories are currently undergoing a long-term accelerated aging test as the final confirmation of their reliability and stability.

  8. Trapped-ion cell with improved DC potential harmonicity for FT-ICR MS

    SciTech Connect (OSTI)

    Tolmachev, Aleksey V.; Robinson, Errol W.; Wu, Si; Kang, Hyuk; Lourette, Natacha M.; Pasa-Tolic, Ljiljana; Smith, Richard D.

    2008-04-01T23:59:59.000Z

    The trapped-ion cell is a key component critical for optimal performance in Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry (MS). We have upgraded our 12 Tesla FT-ICR instrument with a new open cylindrical cell that includes four additional cylindrical segments that serve as compensation electrodes. The DC potential on the additional segments can be set to specific pre-calculated values to suppress DC trapping field anharmonicity, in an effort to improve coherence of the ion cyclotron motion and minimize deviations from the calibration function of the ideal cell. Alternatively, the compensation potentials can be set equal to potentials of adjacent cell electrodes, which creates a DC potential distribution equivalent to that of a regular open cylindrical cell. The initial experimental characterization of both the compensated and open cell configurations was performed using ESI direct infusion of a peptide mixture. Operating the compensated cell at increased post-excitation radii resulted in improved mass measurement accuracy together with increased signal intensity, while the regular configuration exhibited peak splitting and reduced signal life time under these operating conditions. The observed improvement of the compensated cell performance was consistent with the expected behavior due to the improved DC potential harmonicity. These results confirm that the trapping DC potential harmonicity is significant for optimizing FT-ICR MS performance.

  9. Optimization of Direct-Injection H2 Combustion Engine Performance...

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

    2010 -- Washington D.C. ace009wallner2010o.pdf More Documents & Publications Optimization of Direct-Injection H2 Combustion Engine Performance, Efficiency, and Emissions H2...

  10. Self-consistent modeling of DC and microwave nitrogen discharges and their afterglows

    SciTech Connect (OSTI)

    Guerra, Vasco [Centro de Fisica dos Plasmas, Instituto Superior Tecnico, 1049-001 Lisbon (Portugal)

    2004-12-01T23:59:59.000Z

    This report presents an investigation on the modeling of stationary DC and microwave nitrogen discharges and their afterglows, operating at pressures around one Torr and ionization degrees between 10-7-10-4. The model is based on the self-consistent solutions to the electron Boltzmann equation coupled to the rate balance equations for the most important neutral and charged species, the wave electrodynamics characteristics and the gas thermal balance equation. The results are obtained as a function of the usual discharge operating parameters, namely gas pressure, discharge current or electron density, and tube radius. It is shown that the vibrationally excited molecules play a central role in the whole problem, ensuring a strong link between different kinetics and directly contributing to the mechanisms of dissociation and gas heating. Furthermore, vibrationally excited molecules in high vibration levels are in the origin of the peaks observed in the flowing afterglow for the concentrations of several species, such as N{sub 2}(A {sup 3}{sigma}{sub g}{sup +}), N2(B 3{pi}g), N{sub 2}{sup +}(B {sup 2}{sigma}{sub u}{sup +}) and electrons, which occur downstream from the discharge after a dark zone as a consequence of the V-V up-pumping mechanism.

  11. Geothermal Energy: Current abstracts

    SciTech Connect (OSTI)

    Ringe, A.C. (ed.)

    1988-02-01T23:59:59.000Z

    This bulletin announces the current worldwide information available on the technologies required for economic recovery of geothermal energy and its use as direct heat or for electric power production. (ACR)

  12. DC High School Science Bowl Regionals | Department of Energy

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

    DC High School Science Bowl Regionals DC High School Science Bowl Regionals February 22, 2014 1:15PM to 8:15PM EST Department of Energy headquarters - 1000 Independence Ave SW,...

  13. National Science Bowl Brings Best and Brightest to DC | Department...

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

    National Science Bowl Brings Best and Brightest to DC National Science Bowl Brings Best and Brightest to DC April 24, 2012 - 11:14am Addthis The National Science Bowl is the...

  14. National Small Business Federal Contracting Summit-DC Fall Conference...

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

    National Small Business Federal Contracting Summit-DC Fall Conference National Small Business Federal Contracting Summit-DC Fall Conference November 6, 2014 8:00AM to 4:00PM EST...

  15. Federal Government Congressional Budget Office, Budget Analysis Division Washington, DC

    E-Print Network [OSTI]

    Shyy, Wei

    Administration, Center for Drug Evaluation and Research Washington, DC Federal Energy Regulatory CommissionFederal Government Congressional Budget Office, Budget Analysis Division Washington, DC Department Environmental Protection Agency, Office of Transportation & Air Quality Ann Arbor, MI Federal Drug

  16. achyrocline satureioides dc: Topics by E-print Network

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

    and DC, microgrid, with its definition as a local grid that comprises distributed generation, energy storage systems to the frequency in the AC bulk grid, the DC voltage in the...

  17. Halbach array DC motor/generator

    DOE Patents [OSTI]

    Merritt, Bernard T. (Livermore, CA); Dreifuerst, Gary R. (Livermore, CA); Post, Richard F. (Walnut Creek, CA)

    1998-01-01T23:59:59.000Z

    A new configuration of DC motor/generator is based on a Halbach array of permanent magnets. This motor does not use ferrous materials so that the only losses are winding losses and losses due to bearings and windage. An "inside-out" design is used as compared to a conventional motor/generator design. The rotating portion, i.e., the rotor, is on the outside of the machine. The stationary portion, i.e., the stator, is formed by the inside of the machine. The rotor contains an array of permanent magnets that provide a uniform field. The windings of the motor are placed in or on the stator. The stator windings are then "switched" or "commutated" to provide a DC motor/generator much the same as in a conventional DC motor. The commutation can be performed by mechanical means using brushes or by electronic means using switching circuits. The invention is useful in electric vehicles and adjustable speed DC drives.

  18. Halbach array DC motor/generator

    DOE Patents [OSTI]

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

    1998-01-06T23:59:59.000Z

    A new configuration of DC motor/generator is based on a Halbach array of permanent magnets. This motor does not use ferrous materials so that the only losses are winding losses and losses due to bearings and windage. An ``inside-out`` design is used as compared to a conventional motor/generator design. The rotating portion, i.e., the rotor, is on the outside of the machine. The stationary portion, i.e., the stator, is formed by the inside of the machine. The rotor contains an array of permanent magnets that provide a uniform field. The windings of the motor are placed in or on the stator. The stator windings are then ``switched`` or ``commutated`` to provide a DC motor/generator much the same as in a conventional DC motor. The commutation can be performed by mechanical means using brushes or by electronic means using switching circuits. The invention is useful in electric vehicles and adjustable speed DC drives. 17 figs.

  19. FEDERAL ENERGY WASHINGTON, D.C. 20426

    E-Print Network [OSTI]

    Laughlin, Robert B.

    FEDERAL ENERGY REGULATORY COMMISSION WASHINGTON, D.C. 20426 NEWS RELEASE NEWS MEDIA CONTACT judge, the Federal Energy Regulatory Commission today ordered an expedited fact-finding hearing of the discussions. #12;Chairman Curt L. Hébert, Jr. stated as follows: "At some point, regulatory and R-01-33 (more

  20. High pressure, high current, low inductance, high reliability sealed terminals

    DOE Patents [OSTI]

    Hsu, John S. (Oak Ridge, TN) [Oak Ridge, TN; McKeever, John W. (Oak Ridge, TN) [Oak Ridge, TN

    2010-03-23T23:59:59.000Z

    The invention is a terminal assembly having a casing with at least one delivery tapered-cone conductor and at least one return tapered-cone conductor routed there-through. The delivery and return tapered-cone conductors are electrically isolated from each other and positioned in the annuluses of ordered concentric cones at an off-normal angle. The tapered cone conductor service can be AC phase conductors and DC link conductors. The center core has at least one service conduit of gate signal leads, diagnostic signal wires, and refrigerant tubing routed there-through. A seal material is in direct contact with the casing inner surface, the tapered-cone conductors, and the service conduits thereby hermetically filling the interstitial space in the casing interior core and center core. The assembly provides simultaneous high-current, high-pressure, low-inductance, and high-reliability service.

  1. Energy Training Session for DC Elementary School Teachers

    Broader source: Energy.gov [DOE]

    Are you an elementary school teacher in Washington, DC, looking for creative ideas to introduce energy curriculum to your students?

  2. A Three-Phase Bidirectional DC-DC Converter for Automotive Applications

    SciTech Connect (OSTI)

    Su, Gui-Jia [ORNL; Tang, Lixin [ORNL

    2008-01-01T23:59:59.000Z

    This paper presents a three-phase soft-switching, bidirectional dc-dc converter for high-power automotive applications. The converter employs dual three-phase active bridges and operates with a novel asymmetrical but fixed duty cycle for the top and bottom switches of each phase leg. Simulation and experimental data on a 6-kW prototype are included to verify the novel operating and power flow control principles.

  3. Aalborg Universitet Hierarchical Control for Multiple DC Microgrids Clusters

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    Aalborg Universitet Hierarchical Control for Multiple DC Microgrids Clusters Shafiee, Qobad Control for Multiple DC Microgrids Clusters. I E E E Transactions on Energy Conversion. General rights, J. C. Vasquez, and J. M. Guerrero, "Hierarchical Control for Multiple DC-Microgrids Clusters," IEEE

  4. Transportation YOU 2013 DC Youth Summit WTS Transportation YOU

    E-Print Network [OSTI]

    Minnesota, University of

    Transportation YOU 2013 DC Youth Summit WTS Transportation YOU CTS Research Conference May 21, 2014 Lisa Rasmussen, WTS / Kimley-Horn and Associates, Inc #12;Transportation YOU 2013 DC Youth SummitTransportation YOU 2013 DC Youth Summit Agenda What is Transportation YOU? Transportation YOU ­ WTS Local Chapter

  5. A Cascade Multilevel Inverter Using a Single DC Source

    E-Print Network [OSTI]

    Tolbert, Leon M.

    A Cascade Multilevel Inverter Using a Single DC Source Zhong Du1, Leon M. Tolbert2 3, John N inverter can be implemented using only a single DC power source and capacitors. A standard cascade multilevel inverter requires DC sources for 2 + 1 levels. Without requiring transformers, the scheme proposed

  6. SUBMITTED TO: THE D.C. WATER RESOURCES RESEARCH CENTER

    E-Print Network [OSTI]

    District of Columbia, University of the

    chemicals and heavy metals such as lead'. Several published reports have suggested that D.C. public waterMARCH 1996 SUBMITTED TO: THE D.C. WATER RESOURCES RESEARCH CENTER UNIVERSITY OF THE DISTRICT OF COLUMBIA WASHINGTON, D.C. 20008 SUBMITTED BY: DR. KWAMENA OCRAN LEAD IN RESIDENTIAL DRINKING WATER: RISK

  7. Modeling and Optimization of Direct Chill Casting to Reduce Ingot Cracking

    SciTech Connect (OSTI)

    Das, S.K.; Ningileri, S.; Long, Z.; Saito, K.; Khraisheh, M.; Hassan, M.H.; Kuwana, K.; Han, Q.; Viswanathan, S.; Sabau, A.S.; Clark, J.; Hyrn, J. (ANL)

    2006-08-15T23:59:59.000Z

    Approximately 68% of the aluminum produced in the United States is first cast into ingots prior to further processing into sheet, plate, extrusions, or foil. The direct chill (DC) semi-continuous casting process has been the mainstay of the aluminum industry for the production of ingots due largely to its robust nature and relative simplicity. Though the basic process of DC casting is in principle straightforward, the interaction of process parameters with heat extraction, microstructural evolution, and development of solidification stresses is too complex to analyze by intuition or practical experience. One issue in DC casting is the formation of stress cracks [1-15]. In particular, the move toward larger ingot cross-sections, the use of higher casting speeds, and an ever-increasing array of mold technologies have increased industry efficiencies but have made it more difficult to predict the occurrence of stress crack defects. The Aluminum Industry Technology Roadmap [16] has recognized the challenges inherent in the DC casting process and the control of stress cracks and selected the development of 'fundamental information on solidification of alloys to predict microstructure, surface properties, and stresses and strains' as a high-priority research need, and the 'lack of understanding of mechanisms of cracking as a function of alloy' and 'insufficient understanding of the aluminum solidification process', which is 'difficult to model', as technology barriers in aluminum casting processes. The goal of this Aluminum Industry of the Future (IOF) project was to assist the aluminum industry in reducing the incidence of stress cracks from the current level of 5% to 2%. Decreasing stress crack incidence is important for improving product quality and consistency as well as for saving resources and energy, since considerable amounts of cast metal could be saved by eliminating ingot cracking, by reducing the scalping thickness of the ingot before rolling, and by eliminating butt sawing. Full-scale industrial implementation of the results of the proposed research would lead to energy savings in excess of 6 trillion Btu by the year 2020. The research undertaken in this project aimed to achieve this objective by a collaboration of industry, university, and national laboratory personnel through Secat, Inc., a consortium of aluminum companies. During the four-year project, the industrial partners and the research team met in 16 quarterly meetings to discuss research results and research direction. The industrial partners provided guidance, facilities, and experience to the research team. The research team went to two industrial plants to measure temperature distributions in commercial 60,000-lb DC casting ingot production. The project focused on the development of a fundamental understanding of ingot cracking and detailed models of thermal conditions, solidification, microstructural evolution, and stress development during the initial transient in DC castings of the aluminum alloys 3004 and 5182. The microstructure of the DC casting ingots was systematically characterized. Carefully designed experiments were carried out at the national laboratory and university facilities as well as at the industrial locations using the industrial production facilities. The advanced computational capabilities of the national laboratories were used for thermodynamic and kinetic simulations of phase transformation, heat transfer and fluid flow, solidification, and stress-strain evolution during DC casting. The achievements of the project are the following: (1) Identified the nature of crack formation during DC casting; (2) Developed a novel method for determining the mechanical properties of an alloy at the nonequilibrium mushy zone of the alloy; (3) Measured heat transfer coefficients (HTCs) between the solidifying ingot and the cooling water jet; (4) Determined the material constitutive model at high temperatures; and (5) Developed computational capabilities for the simulation of cracking formation in DC casting ingot. The models and the database de

  8. Directives Tools

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

    Useful links and resources for Directives Writers, Directives Point of Contact (DPCs), Subject Matter Experts (SMEs), and Draft Directive Reviewers.

  9. Ocean indicators Current knowledge and future directions

    E-Print Network [OSTI]

    -016-00) Hatchery Wild #12;Spatial distribution is stock-specific #12;Steelhead R2 = 0.68 Group A with 1-year lag R2 of mechanistic understanding · Plugging in to management #12;Managing for Harvest Egg take Escapement (hatchery

  10. Current Directions in Freight and Logistics Industry

    E-Print Network [OSTI]

    Minnesota, University of

    Sources: Department of Energy & ATASources: Department of Energy & ATA #12;Rural Manufacturing Plants

  11. Pacific Direct Current Intertie (PDCI) Upgrade Project

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - September 2006 TheSteven Ashby Dr. Steven Para9 Revision: 0 Issued:

  12. Sandia National Laboratories: direct-current motor

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1development Sandia, NRELdeep-water multiple-megawatt

  13. Disc rotors with permanent magnets for brushless DC motor

    SciTech Connect (OSTI)

    Hawsey, Robert A. (Oak Ridge, TN); Bailey, J. Milton (Knoxville, TN)

    1992-01-01T23:59:59.000Z

    A brushless dc permanent magnet motor drives an autonomous underwater vehe. In one embodiment, the motor comprises four substantially flat stators in stacked relationship, with pairs of the stators axially spaced, each of the stators comprising a tape-wound stator coil, and first and second substantially flat rotors disposed between the spaced pairs of stators. Each of the rotors includes an annular array of permanent magnets embedded therein. A first shaft is connected to the first rotor and a second, concentric shaft is connected to the second rotor, and a drive unit causes rotation of the two shafts in opposite directions. The second shaft comprises a hollow tube having a central bore in which the first shaft is disposed. Two different sets of bearings support the first and second shafts. In another embodiment, the motor comprises two ironless stators and pairs of rotors mounted on opposite sides of the stators and driven by counterrotating shafts.

  14. Generating expansion model incorporating compact DC power flow equations

    SciTech Connect (OSTI)

    Nderitu, D.G.; Sparrow, F.T.; Yu, Z. [Purdue Inst. for Interdisciplinary Engineering Studies, West Lafayette, IN (United States)

    1998-12-31T23:59:59.000Z

    This paper presents a compact method of incorporating the spatial dimension into the generation expansion problem. Compact DC power flow equations are used to provide real-power flow coordination equations. Using these equations the marginal contribution of a generator to th total system loss is formulated as a function of that generator`s output. Incorporating these flow equations directly into the MIP formulation of the generator expansion problem results in a model that captures a generator`s true net marginal cost, one that includes both the cost of generation and the cost of transport. This method contrasts with other methods that iterate between a generator expansion model and an optimal power flow model. The proposed model is very compact and has very good convergence performance. A case study with data from Kenya is used to provide a practical application to the model.

  15. Possible temperature control DC switch effect between two superconductors

    E-Print Network [OSTI]

    Tian De Cao

    2011-08-11T23:59:59.000Z

    The lifetime of an electron pair could not be unlimited long, on the basis of this, we suggest a model. The model means that the movements of charge carriers in a superconductor should have three forms: the single-electron movement, the single-pair movement, and the revolving around the mass center of two electrons in a pair. Thus the current in a superconductor has three possible parts. Similarly, there should be three possible effects in a SIS junction: the tunneling of single electron, the tunneling of single pair, and the pair-forming following the pair-breaking. This paper will discuss these problems and present a possible temperature control DC switch effect between two superconductors.

  16. Discharging a DC bus capacitor of an electrical converter system

    DOE Patents [OSTI]

    Kajouke, Lateef A; Perisic, Milun; Ransom, Ray M

    2014-10-14T23:59:59.000Z

    A system and method of discharging a bus capacitor of a bidirectional matrix converter of a vehicle are presented here. The method begins by electrically shorting the AC interface of the converter after an AC energy source is disconnected from the AC interface. The method continues by arranging a plurality of switching elements of a second energy conversion module into a discharge configuration to establish an electrical current path from a first terminal of an isolation module, through an inductive element, and to a second terminal of the isolation module. The method also modulates a plurality of switching elements of a first energy conversion module, while maintaining the discharge configuration of the second energy conversion module, to at least partially discharge a DC bus capacitor.

  17. Stray currents -- Generation, interference effects and control

    SciTech Connect (OSTI)

    Nikolakakos, S. [Raytheon Engineers and Constructors, Inc., Lyndhurst, NJ (United States)

    1998-12-31T23:59:59.000Z

    Stray currents, mostly known for their detrimental corrosion affects on the underground structures, can be effectively controlled by the implementation of specific measures at both the source of generation and at the affected structure(s). This paper discusses the most serious sources of stray current generation, the resulting problems and the numerous control methods that can be utilized to minimize corrosion and safety problems. Safety concerns associated with dc power systems are also discussed.

  18. DC side filters for multiterminal HVDC systems

    SciTech Connect (OSTI)

    Shore, N.L.; Adamson, K.; Bard, P. [and others] [and others

    1996-10-01T23:59:59.000Z

    Multiterminal HVDC systems present challenges in the specification and design of suitable dc side filtering. This document examines the existing experience and addresses the particular technical problems posed by multiterminal systems. The filtering requirements of small taps are discussed, as is the potential use of active filters. Aspects of calculation and design are considered and recommendations made to guide the planners and designers of future multiterminal schemes.

  19. Good Energies (Washington DC) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia: Energy Resources Jump to: navigation,Ohio: Energy Resources Jump to:GloriaGoldenGolden,CookWashington DC) Jump

  20. Modeling a short dc discharge with thermionic cathode and auxiliary anode

    SciTech Connect (OSTI)

    Bogdanov, E. [St. Petersburg State University, St. Petersburg 199034 (Russian Federation) [St. Petersburg State University, St. Petersburg 199034 (Russian Federation); University ITMO, Kronverkskiy pr. 49, St. Petersburg 197101 (Russian Federation); Demidov, V. I. [St. Petersburg State University, St. Petersburg 199034 (Russian Federation) [St. Petersburg State University, St. Petersburg 199034 (Russian Federation); West Virginia University, Morgantown, West Virginia 26506 (United States); Kaganovich, I. D. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)] [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Koepke, M. E. [West Virginia University, Morgantown, West Virginia 26506 (United States)] [West Virginia University, Morgantown, West Virginia 26506 (United States); Kudryavtsev, A. A. [St. Petersburg State University, St. Petersburg 199034 (Russian Federation)] [St. Petersburg State University, St. Petersburg 199034 (Russian Federation)

    2013-10-15T23:59:59.000Z

    A short dc discharge with a thermionic cathode can be used as a current and voltage stabilizer, but is subject to current oscillation. If instead of one anode two anodes are used, the current oscillations can be reduced. We have developed a kinetic model of such a discharge with two anodes, where the primary anode has a small opening for passing a fraction of the discharge current to an auxiliary anode. The model demonstrates that the current-voltage relationship of the discharge with two anodes is characterized everywhere by positive slope, i.e., positive differential resistance. Therefore, the discharge with two anodes is expected to be stable to the spontaneous oscillation in current that is induced by negative differential resistance. As a result, such a discharge can be used in an engineering application that requires stable plasma, such as a current and voltage stabilizer.

  1. Performance Evaluation of a Multi-Port DC-DC Current Source Converter for High Power Applications

    E-Print Network [OSTI]

    Yancey, Billy Ferrall

    2011-08-08T23:59:59.000Z

    ? ? Fig. 10. Three step phase shift from ? = 0? to ? = -90?. ? = 0?, and the new phase angle is ?n e w = 90?. A three step timing sequence should be implemented for every 90? phase shift to prevent capacitor spikes and voltage biasing. A bang-bang...

  2. Demonstration of Cathode Emittance Dominated High Bunch Charge Beams in a DC gun-based Photoinjector

    E-Print Network [OSTI]

    Gulliford, Colwyn; Bazarov, Ivan; Dunham, Bruce; Cultrera, Luca

    2015-01-01T23:59:59.000Z

    We present the results of transverse emittance and longitudinal current profile measurements of high bunch charge (greater than or equal to 100 pC) beams produced in the DC gun-based Cornell Energy Recovery Linac Photoinjector. In particular, we show that the cathode thermal and core beam emittances dominate the final 95% and core emittance measured at 9-9.5 MeV. Additionally, we demonstrate excellent agreement between optimized 3D space charge simulations and measurement, and show that the quality of the transverse laser distribution limits the optimal simulated and measured emittances. These results, previously thought achievable only with RF guns, demonstrate that DC gun based photoinjectors are capable of delivering beams with sufficient single bunch charge and beam quality suitable for many current and next generation accelerator projects such as Energy Recovery Linacs (ERLs) and Free Electron Lasers (FELs).

  3. Method of measuring the dc electric field and other tokamak parameters

    DOE Patents [OSTI]

    Fisch, Nathaniel J. (Princeton, NJ); Kirtz, Arnold H. (Princeton Junction, NJ)

    1992-01-01T23:59:59.000Z

    A method including externally imposing an impulsive momentum-space flux to perturb hot tokamak electrons thereby producing a transient synchrotron radiation signal, in frequency-time space, and the inference, using very fast algorithms, of plasma parameters including the effective ion charge state Z.sub.eff, the direction of the magnetic field, and the position and width in velocity space of the impulsive momentum-space flux, and, in particular, the dc toroidal electric field.

  4. A new approach to modelling the impact of EMI on MOSFET DC behaviour R. Fernndez-Garca, 1

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    the DC MOSFET behaviour under electromagnetic interference (EMI) is presented. The model is able-power law directly applied to a MOSFET under EMI impact. KEYWORDS: MOSFET, Electromagnetic Interference (EMI: Electronic systems are disturbed by electromagnetic interference (EMI) which can potentially disrupt

  5. Design and implementation of a scalable encryption processor with embedded variable dc/dc converter

    E-Print Network [OSTI]

    James Goodman; Anantha Chandrakasan; Abram P. Dancy

    1999-01-01T23:59:59.000Z

    This work describes the design and implementation of an energy-efficient, scalable encryption processor that utilizes variable voltage supply techniques and a highefficiency embedded variable output DC/DC converter. The resulting implementation dissipates 134nJ/bit @ V DD = 2.5V, when encrypting at its maximum rate of 1Mb/s using a maximum datapath width of 512 bits. The embedded converter achieves an efficiency of 96 % at this peak load. The processor is 2-3 orders of magnitude more energy efficient than optimized assembly code running on a low-power processor such as the StrongARM. 2.

  6. DC-DC Converter Topology Assessment for Large Scale Distributed Photovoltaic Plant Architectures

    SciTech Connect (OSTI)

    Mohammed S. Agamy; Maja Harfman-Todorovic; Ahmed Elasser; Juan A. Sabate; Robert L. Steigerwald; Yan Jiang; Somasundaram Essakiappan

    2011-07-01T23:59:59.000Z

    Distributed photovoltaic (PV) plant architectures are emerging as a replacement for the classical central inverter based systems. However, power converters of smaller ratings may have a negative impact on system efficiency, reliability and cost. Therefore, it is necessary to design converters with very high efficiency and simpler topologies in order not to offset the benefits gained by using distributed PV systems. In this paper an evaluation of the selection criteria for dc-dc converters for distributed PV systems is performed; this evaluation includes efficiency, simplicity of design, reliability and cost. Based on this evaluation, recommendations can be made as to which class of converters is best fit for this application.

  7. A Bi-Directional DC-DC Converter with Minimum Energy Storage Elements Leon M. Tolbert1,3

    E-Print Network [OSTI]

    Tolbert, Leon M.

    uses an internal combustion diesel engine to drive a radial-gap permanent magnet alternator at variable frequency, variable voltage produced by the permanent magnet alternator is diode-rectified to a high voltage synchronous machines are presently used to convert the mechanical power of the rotating shaft into three

  8. Directed Energy

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

    Directed Energy The Directed Energy Program provides laser systems design, engineering and production for specific applications and missions, experimentally validated...

  9. Dc's blog | OpenEI Community

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublic Utilities Address:011-DNA Jump to:52c8ff988c1 No38e4011f618b No revision hasDawesCountyNewDc's blog Home

  10. RES D.C. | Department of Energy

    Office of Environmental Management (EM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "of Energy Power.pdf11-161-LNG |September 15,2015 | DepartmentLoans |QuerylNuclear Power Plant DocketRES D.C.

  11. Fun D.C. Jobs for Physicists

    SciTech Connect (OSTI)

    Clark Cully

    2009-09-30T23:59:59.000Z

    Physicists make valuable contributions in a wide variety of careers, including those in Washington. Many national challenges, including energy, innovation, and security, create a demand for technically-competent individuals across government. Clark will discuss some of the many programs in D.C. designed to attract the best and brightest minds, from grad-students to professors, from short-term assignments to whole new careers. These are great opportunities to use your expertise and enrich your knowledge of the broader scientific enterprise, all while serving society.

  12. User:Dc | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revisionEnvReviewNonInvasiveExplorationUT-gTagusparkCalculator JumpUnitedBeowaweColin.mccormick JumpDbowers JumpDc

  13. Sandia National Laboratories: DC power optimizers

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -the Mid-Infrared0EnergySandia Involves Wind-FarmCool EarthSafetyCzech RadioactiveDC

  14. Electric current locator

    DOE Patents [OSTI]

    King, Paul E. (Corvallis, OR); Woodside, Charles Rigel (Corvallis, OR)

    2012-02-07T23:59:59.000Z

    The disclosure herein provides an apparatus for location of a quantity of current vectors in an electrical device, where the current vector has a known direction and a known relative magnitude to an input current supplied to the electrical device. Mathematical constants used in Biot-Savart superposition equations are determined for the electrical device, the orientation of the apparatus, and relative magnitude of the current vector and the input current, and the apparatus utilizes magnetic field sensors oriented to a sensing plane to provide current vector location based on the solution of the Biot-Savart superposition equations. Description of required orientations between the apparatus and the electrical device are disclosed and various methods of determining the mathematical constants are presented.

  15. Wide input range DC-DC converter with digital control scheme

    E-Print Network [OSTI]

    Harfman Todorovic, Maja

    2006-04-12T23:59:59.000Z

    boost converter a battery or ultracapacitor energy storage is connected to take care of the fuel cell slow transient response (200 watts/min). The robust features of the proposed control system ensure a constant output DC voltage for a variety of load...

  16. XL-DC/Mark V Options You can customize the XL-DC and Mark V

    E-Print Network [OSTI]

    Berns, Hans-Gerd

    administrator with the NTP Time Server Protocol, network status, and statistics. This feature implements SNMP. XL-DC Mark V Network Time Server Telecommunications Interface Frequency Measurement STD Time Interface Low Phase Noise Output Network Interface Loss of Lock Alarm STD Programmable Pulse Output

  17. Washington DC Reliability Requirements and the Need to Operate...

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

    Washington DC Reliability Requirements and the Need to Operate Mirant's Potomac River Generation Station to Support Local Area Reliability (Oak Ridge National Laboratory 2005)...

  18. PHOTOVOLTAIC DC ARC FAULT DETECTOR TESTING AT SANDIA NATIONAL

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

    PHOTOVOLTAIC DC ARC FAULT DETECTOR TESTING AT SANDIA NATIONAL LABORATORIES Jay Johnson 1 , Birger Pahl 2 , Charles Luebke 2 , Tom Pier 2 , Theodore Miller 3 , Jason Strauch 1 ,...

  19. DC Resistivity Survey (Wenner Array) At Mt Princeton Hot Springs...

    Open Energy Info (EERE)

    Determination of groundwater flux patterns Notes Researchers measured DC resistivity and produced 12 resistivity profiles, each approximately 1.3 km in length. Equilibrium...

  20. DC Bus Capacitor Manufacturing Facility for Electric Drive Vehicles...

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

    0 DOE Vehicle Technologies and Hydrogen Programs Annual Merit Review and Peer Evaluation Meeting, June 7-11, 2010 -- Washington D.C. apearravt028boan2010...

  1. Energy Challenge Two: The WeatherizeDC Campaign | Department...

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

    economic and environmental justice by creating clean energy career opportunities for people who need them most. The DC Project applies cutting-edge organizing tools and tactics...

  2. Current Rusume

    E-Print Network [OSTI]

    2015-02-09T23:59:59.000Z

    Research Interest Rough paths theory, Stochastic differential equations, ... I am currently working on a problem about stochastic analysis on Riemannian folia-.

  3. Catalog of DC Appliances and Power Systems

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01T23:59:59.000Z

    current residential refrigerators and freezers rulemaking,Refrigerator/Freezers. .Refrigerator, Refrigerator-Freezer, and Freezers Rulemaking,

  4. Parallel 3D Finite Element Numerical Modelling of DC Electron Guns

    SciTech Connect (OSTI)

    Prudencio, E.; Candel, A.; Ge, L.; Kabel, A.; Ko, K.; Lee, L.; Li, Z.; Ng, C.; Schussman, G.; /SLAC

    2008-02-04T23:59:59.000Z

    In this paper we present Gun3P, a parallel 3D finite element application that the Advanced Computations Department at the Stanford Linear Accelerator Center is developing for the analysis of beam formation in DC guns and beam transport in klystrons. Gun3P is targeted specially to complex geometries that cannot be described by 2D models and cannot be easily handled by finite difference discretizations. Its parallel capability allows simulations with more accuracy and less processing time than packages currently available. We present simulation results for the L-band Sheet Beam Klystron DC gun, in which case Gun3P is able to reduce simulation time from days to some hours.

  5. New current control concept -- Minimum time current control in the three-phase PWM converter

    SciTech Connect (OSTI)

    Choi, J.W. [LG Industrial Systems, Seoul (Korea, Republic of); Sul, S.K. [Seoul National Univ. (Korea, Republic of). School of Electrical Engineering

    1997-01-01T23:59:59.000Z

    In this paper, a new current controller that guarantees the fastest transient response is proposed. The basic concept is to find the optimal control voltage for tracking the reference current with minimum time under the voltage limit constraint. Though this minimum time control concept is also applicable to all the machine drive systems, this paper focuses on the current regulation in the three-phase pulse width modulation (PWM) converter. In the simulation and experimental results, it is observed that the proposed controller has much less transient time than the conventional synchronous PI regulator and the performance of the dc link voltage control is also greatly improved with the proposed current controller.

  6. High-Compression-Ratio; Atkinson-Cycle Engine Using Low-Pressure Direct Injection and Pneumatic-Electronic Valve Actuation Enabled by Ionization Current and Foward-Backward Mass Air Flow Sensor Feedback

    SciTech Connect (OSTI)

    Harold Schock; Farhad Jaberi; Ahmed Naguib; Guoming Zhu; David Hung

    2007-12-31T23:59:59.000Z

    This report describes the work completed over a two and one half year effort sponsored by the US Department of Energy. The goal was to demonstrate the technology needed to produce a highly efficient engine enabled by several technologies which were to be developed in the course of the work. The technologies included: (1) A low-pressure direct injection system; (2) A mass air flow sensor which would measure the net airflow into the engine on a per cycle basis; (3) A feedback control system enabled by measuring ionization current signals from the spark plug gap; and (4) An infinitely variable cam actuation system based on a pneumatic-hydraulic valve actuation These developments were supplemented by the use of advanced large eddy simulations as well as evaluations of fuel air mixing using the KIVA and WAVE models. The simulations were accompanied by experimental verification when possible. In this effort a solid base has been established for continued development of the advanced engine concepts originally proposed. Due to problems with the valve actuation system a complete demonstration of the engine concept originally proposed was not possible. Some of the highlights that were accomplished during this effort are: (1) A forward-backward mass air flow sensor has been developed and a patent application for the device has been submitted. We are optimistic that this technology will have a particular application in variable valve timing direct injection systems for IC engines. (2) The biggest effort on this project has involved the development of the pneumatic-hydraulic valve actuation system. This system was originally purchased from Cargine, a Swedish supplier and is in the development stage. To date we have not been able to use the actuators to control the exhaust valves, although the actuators have been successfully employed to control the intake valves. The reason for this is the additional complication associated with variable back pressure on the exhaust valves when they are opened. As a result of this effort, we have devised a new design and have filed for a patent on a method of control which is believed to overcome this problem. The engine we have been working with originally had a single camshaft which controlled both the intake and exhaust valves. Single cycle lift and timing control was demonstrated with this system. (3) Large eddy simulations and KIVA based simulations were used in conjunction with flow visualizations in an optical engine to study fuel air mixing. During this effort we have devised a metric for quantifying fuel distribution and it is described in several of our papers. (4) A control system has been developed to enable us to test the benefits of the various technologies. This system used is based on Opal-RT hardware and is being used in a current DOE sponsored program.

  7. Direct modelling of envelope dynamics in resonant inverters

    E-Print Network [OSTI]

    Direct modelling of envelope dynamics in resonant inverters Y. Yin, R. Zane, R. Erickson and J. Glaser A direct dynamic modelling approach is proposed for envelope signals in resonant inverters tank and simplify analysis and controller design. Introduction: High-frequency DC-AC inverters

  8. EE443L Lab 2: Modeling a DC Motor Introduction

    E-Print Network [OSTI]

    Wedeward, Kevin

    : In this lab we will develop and validate a basic model of a permanent magnet DC motor (Yaskawa Electric MINI: The DC motor is a common actuator in control systems that converts electrical energy into rotational Procedure: Through the following steps, motor parameters for the Yaskawa Electric MINI-Minertia motor

  9. Read-out electronics for DC squid magnetic measurements

    DOE Patents [OSTI]

    Ganther, Jr., Kenneth R. (Olathe, KS); Snapp, Lowell D. (Independence, MO)

    2002-01-01T23:59:59.000Z

    Read-out electronics for DC SQUID sensor systems, the read-out electronics incorporating low Johnson noise radio-frequency flux-locked loop circuitry and digital signal processing algorithms in order to improve upon the prior art by a factor of at least ten, thereby alleviating problems caused by magnetic interference when operating DC SQUID sensor systems in magnetically unshielded environments.

  10. ELECTROMAGNETIC RADIATION FROM A STRONG DC ELECTRIC FIELD

    E-Print Network [OSTI]

    Guedel, Manuel

    ELECTROMAGNETIC RADIATION FROM A STRONG DC ELECTRIC FIELD Manuel G¨udel 1 and Donat G. Wentzel 2 1 accelerated by a strong dc electric field show not only very efficient generation of beam waves but also emission of o­mode radiation. We present a set of particle simulations for which we study the behavior

  11. Dynamic microscopic theory of fusion using DC-TDHF

    SciTech Connect (OSTI)

    Umar, A. S.; Oberacker, V. E.; Keser, R.; Maruhn, J. A.; Reinhard, P.-G. [Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37235 (United States); RTE University, Science and Arts Faculty, Department of Physics, 53100, Rize (Turkey); Institut fuer Theoretische Physik, Goethe-Universitaet, D-60438 Frankfurt am Main (Germany); Institut fur Theoretische Physik, Universitat Erlangen, D-91054 Erlangen (Germany)

    2012-10-20T23:59:59.000Z

    The density-constrained time-dependent Hartree-Fock (DC-TDHF) theory is a fully microscopic approach for calculating heavy-ion interaction potentials and fusion cross sections below and above the fusion barrier. We discuss recent applications of DC-TDHF method to fusion of light and heavy systems.

  12. An Economic Impact Analysis of DC Drinking Water Quality

    E-Print Network [OSTI]

    District of Columbia, University of the

    An Economic Impact Analysis of DC Drinking Water Quality Annual Progress Report for FY 2005 In January 2004, District of Columbia residents learned the drinking water supplied by the D.C. Water immediately responded by forming the Interagency Task Force on Lead in Drinking Water (The Task Force

  13. Stray current interference control for HVDC earth currents

    SciTech Connect (OSTI)

    Fitzgerald, J.H. III [PSG Corrosion Engineering/Corrpro Cos., Detroit, MI (United States); Kroon, D.H. [Corrpro Companies Inc., Spring, TX (United States)

    1995-06-01T23:59:59.000Z

    High-voltage direct current (HVDC) transmission lines exist around the world, with several in the US. When one conductor must be taken out of operation (in case of emergency), the earth may be used as an alternate conductor. The earth current may be accumulated on and discharged from underground metallic structures that cross the voltage gradient created by the current. Test results on two lines showed that stray current interference is not a major problem if mitigated properly.

  14. Stabilization of unstable periodic orbits in dc drives

    E-Print Network [OSTI]

    Krishnendu Chakrabarty; Urmila Kar

    2014-02-22T23:59:59.000Z

    Electric drive using dc shunt motor or permanent magnet dc (PMDC) motor as prime mover exhibits bifurcation and chaos. The characteristics of dc shunt and PMDC motors are linear in nature. These motors are controlled by pulse width modulation (PWM) technique with the help of semiconductor switches. These switches are nonlinear element that introduces nonlinear characteristics in the drive. Any nonlinear system can exhibit bifurcation and chaos. dc shunt or PMDC drives show normal behavior with certain range of parameter values. It is also observed that these drive show chaos for significantly large ranges of parameter values. In this paper we present a method for controlling chaos applicable to dc shunt and PMDC drives. The results of numerical investigation are presented.

  15. DC, AC and advanced EV propulsion systems

    SciTech Connect (OSTI)

    O'Neil, W.

    1983-08-01T23:59:59.000Z

    Battery development and liquid fuel availability and cost are still the pacing factors in wide scale electric vehicle introduction. Propulsion systems also require technical development, however, if electric vehicles are to be acceptable in the marketplace in competition against ICE vehicles. Eaton Corporation has undertaken a program designed to identify and investigate three broad types of propulsion systems in identical test vehicles on the same test track under conditions as similar as possible. Characteristics of dc, ac and advanced systems are compared to date, and projections of anticipated results and further work are provided. The compelling advantages of multiple mechanical ratios in EV propulsion systems are reviewed. An emerging, but less obvious, advantage is higher overall system efficiency.

  16. Abstract --A systematic framework for reliability assessment and fault-tolerant design of multiphase dc-dc

    E-Print Network [OSTI]

    Liberzon, Daniel

    reliability. Index Terms--Markov reliability modeling, maximum power point tracking, photovoltaics, switch1 Abstract -- A systematic framework for reliability assessment and fault-tolerant design of multiphase dc-dc converters deployed in photovoltaic applications is presented. System-level steady

  17. Annual Meeting of Energy Recovery Council, W hi DC D b 3 2011Washington DC, December 3. 2011

    E-Print Network [OSTI]

    Columbia University

    Annual Meeting of Energy Recovery Council, W hi DC D b 3 2011Washington DC, December 3. 2011 to the recyclers (e.g. metal smelters; secondary paper mills).(e.g. metal smelters; secondary paper mills). All, recovery (called WastetoEnergy; WTE) gy, , y ( gy; ) · All countries (and communities) who rely on WTE also

  18. We Have a Winner - DC High School Regional Science Bowl Competition...

    Office of Environmental Management (EM)

    We Have a Winner - DC High School Regional Science Bowl Competition Held Last Saturday We Have a Winner - DC High School Regional Science Bowl Competition Held Last Saturday...

  19. Current Titles

    SciTech Connect (OSTI)

    Various

    2006-06-01T23:59:59.000Z

    This booklet is published for those interested in current research being conducted at the National Center for Electron Microscopy. The NCEM is a DOE-designated national user facility and is available at no charge to qualified researchers. Access is controlled by an external steering committee. Interested researchers may contact Jane Cavlina, Administrator, at 510/486-6036.

  20. Implementing the DC Mode in Cosmological Simulations with Supercomoving Variables

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

    Gnedin, Nickolay Y.; Kravtsov, Andrey V.; Rudd, Douglas H.

    2011-06-02T23:59:59.000Z

    As emphasized by previous studies, proper treatment of the density fluctuation on the fundamental scale of a cosmological simulation volume - the 'DC mode' - is critical for accurate modeling of spatial correlations on scales ~> 10% of simulation box size. We provide further illustration of the effects of the DC mode on the abundance of halos in small boxes and show that it is straightforward to incorporate this mode in cosmological codes that use the 'supercomoving' variables. The equations governing evolution of dark matter and baryons recast with these variables are particularly simple and include the expansion factor, and hence the effect of the DC mode, explicitly only in the Poisson equation.

  1. NOISE AND OPTIMIZATION OF THE dc SQUID

    E-Print Network [OSTI]

    Tesche, Claudia Denke

    2011-01-01T23:59:59.000Z

    I o critical current of single Josephson junction.shunt resistance of single Josephson junction.capacitance of single Josephson junction. flux quantum, ~o R

  2. Radiofrequency amplifier based on a dc superconducting quantum interference device

    DOE Patents [OSTI]

    Hilbert, Claude (Berkeley, CA); Martinis, John M. (Berkeley, CA); Clarke, John (Berkeley, CA)

    1986-01-01T23:59:59.000Z

    A low noise radiofrequency amplifier (10), using a dc SQUID (superconducting quantum interference device) as the input amplifying element. The dc SQUID (11) and an input coil (12) are maintained at superconductivity temperatures in a superconducting shield (13), with the input coil (12) inductively coupled to the superconducting ring (17) of the dc SQUID (11). A radiofrequency signal from outside the shield (13) is applied to the input coil (12), and an amplified radiofrequency signal is developed across the dc SQUID ring (17) and transmitted to exteriorly of the shield (13). A power gain of 19.5.+-.0.5 dB has been achieved with a noise temperature of 1.0.+-.0.4 K. at a frequency of 100 MHz.

  3. Radiofrequency amplifier based on a dc superconducting quantum interference device

    DOE Patents [OSTI]

    Hilbert, C.; Martinis, J.M.; Clarke, J.

    1984-04-27T23:59:59.000Z

    A low noise radiofrequency amplifer, using a dc SQUID (superconducting quantum interference device) as the input amplifying element. The dc SQUID and an input coil are maintained at superconductivity temperatures in a superconducting shield, with the input coil inductively coupled to the superconducting ring of the dc SQUID. A radiofrequency signal from outside the shield is applied to the input coil, and an amplified radiofrequency signal is developed across the dc SQUID ring and transmitted to exteriorly of the shield. A power gain of 19.5 +- 0.5 dB has been achieved with a noise temperature of 1.0 +- 0.4 K at a frequency of 100 MHz.

  4. Washington, D.C. and Indiana: Allison Hybrid Technology Achieves...

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

    D.C. region, and demand continues to grow worldwide. The Washington Metropolitan Area Transit Authority (WMATA), with a total fleet of 1,480 buses, has more than 600 of them...

  5. Modeling Microinverters and DC Power Optimizers in PVWatts

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

    and DC Power Optimizers in PVWatts Sara MacAlpine and Chris Deline National Renewable Energy Laboratory Technical Report NRELTP-5J00-63463 February 2015 NREL is a national...

  6. Current Contracts

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinanInformation InInformationCenterResearchCASLNanoporousTestimonyContact Us -SeparationsRelevantCurrent

  7. Indirectly sensing accelerator beam currents for limiting maximum beam current magnitude

    DOE Patents [OSTI]

    Bogaty, J.M.; Clifft, B.E.; Bollinger, L.M.

    1995-08-08T23:59:59.000Z

    A beam current limiter is disclosed for sensing and limiting the beam current in a particle accelerator, such as a cyclotron or linear accelerator, used in scientific research and medical treatment. A pair of independently operable capacitive electrodes sense the passage of charged particle bunches to develop an RF signal indicative of the beam current magnitude produced at the output of a bunched beam accelerator. The RF signal produced by each sensing electrode is converted to a variable DC voltage indicative of the beam current magnitude. The variable DC voltages thus developed are compared to each other to verify proper system function and are further compared to known references to detect beam currents in excess of pre-established limits. In the event of a system malfunction, or if the detected beam current exceeds pre-established limits, the beam current limiter automatically inhibits further accelerator operation. A high Q tank circuit associated with each sensing electrode provides a narrow system bandwidth to reduce noise and enhance dynamic range. System linearity is provided by injecting, into each sensing electrode, an RF signal that is offset from the bunching frequency by a pre-determined beat frequency to ensure that subsequent rectifying diodes operate in a linear response region. The system thus provides a large dynamic range in combination with good linearity. 6 figs.

  8. Analysis and design of a saturable reactor assisted soft-switching full-bridge dc-dc converter

    SciTech Connect (OSTI)

    Hamada, Satoshi (Sansha Electric Manufacturing Co., Ltd., Osaka (Japan)); Nakaoka, Mutsuo (Kobe Univ. (Japan). Dept. of Electrical and Electronics Engineering)

    1994-05-01T23:59:59.000Z

    Analysis and design considerations for a saturable reactor assisted soft-switching full-bridge dc-dc converter are presented. The converter has advantages such as low switching losses with no substantial increase in conduction losses, wide load range, and constant frequency operation. To show how to utilize the analysis results, a 350-W, 500-kHz converter is chosen as a design example. The results are verified experimentally on a prototype converter.

  9. Reid Rosnick/DC/USEPA/US 10/25/2012 11:54 AM

    E-Print Network [OSTI]

    EPA-694 Reid Rosnick/DC/USEPA/US 10/25/2012 11:54 AM To Philip Egidi cc bcc Subject Re: Subpart W Pennsylvania Ave., NW Washington, DC 20460 202.343.9563 rosnick.reid@epa.gov -----Philip Egidi/DC/USEPA/US wrote: ----- To: Reid Rosnick/DC/USEPA/US@EPA From: Philip Egidi/DC/USEPA/US Date: 10/25/2012 11:41AM Cc

  10. Directives System

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

    1998-01-30T23:59:59.000Z

    The Department of Energy (DOE) Directives System is the means by which DOE policies, requirements, and responsibilities are developed and communicated throughout the Department. Directives are used to inform, direct, and guide employees in the performance of their jobs, and to enable employees to work effectively within the Department and with agencies, contractors, and the public. Cancels: DOE O 251.1, DOE M 251.1-1

  11. Gain, directionality and noise in microwave SQUID amplifiers: Input-output approach

    E-Print Network [OSTI]

    Archana Kamal; John Clarke; Michel Devoret

    2012-06-20T23:59:59.000Z

    We present a new theoretical framework to analyze microwave amplifiers based on the dc SQUID. Our analysis applies input-output theory generalized for Josephson junction devices biased in the running state. Using this approach we express the high frequency dynamics of the SQUID as a scattering between the participating modes. This enables us to elucidate the inherently nonreciprocal nature of gain as a function of bias current and input frequency. This method can, in principle, accommodate an arbitrary number of Josephson harmonics generated in the running state of the junction. We report detailed calculations taking into account the first few harmonics that provide simple semi-quantitative results showing a degradation of gain, directionality and noise of the device as a function of increasing signal frequency. We also discuss the fundamental limits on device performance and applications of this formalism to real devices.

  12. A Completely Modular Power Converter for High-Power High-Current DC Applications

    E-Print Network [OSTI]

    Paderborn, Universität

    and filter components. Reliability and availability are other important requirements from the power converter connection of semiconductor devices, however, several centralized components (filters, transformer etc.) are used, which lead to multiple failure modes. Replacement of these large power components is both time

  13. The War of the Currents: AC vs. DC Power | Department of Energy

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion |Energy UsageAUDITVehiclesTankless or Demand-Type Water HeatersFlickr TheHighDevelopmenttheThe

  14. The 100,000 amp dc power supply for a staged hadron collider superferric magnet

    SciTech Connect (OSTI)

    Hays, Steven L.; Claypool, Bradley; Foster, G.William; /Fermilab

    2005-09-01T23:59:59.000Z

    A 1.5 volt 100,000 amp DC switcher power supply was developed for testing a superferric magnet string at FNAL. This supply was used during testing as both the ramping supply and holding supply powering a single magnet load with a total load resistance of 0.7{micro} Ohms. The supply consists of ten paralleled switcher cells, powered by a 400 volt/600 Amp DC power supply. Each cell consists of an IGBT H-bridge driving a step-down transformer at a switching frequency of 2 kHz. The transformer has an effective turns ratio of 224:1. The secondary consists of 32 parallel single-turn full wave rectifier windings. The rectification is done with 64 Shottky diodes. Each cell is rated at 1.5 volts/10,000 amps. During this test each cell was operated as a constant power source without load current or field feedback. This paper will describe the design of the switcher cell and control system used during testing. We will also describe the next level of improvements to the current feedback system to improve the ramp control.

  15. DESIGN OF A DC/RF PHOTOELECTRON GUN.

    SciTech Connect (OSTI)

    YU,D.NEWSHAM,Y.SMIRONOV,A.YU,J.SMEDLEY,J.SRINIVASAN RAU,T.LEWELLEN,J.ZHOLENTS,A.

    2003-05-12T23:59:59.000Z

    An integrated dc/rf photoelectron gun produces a low-emittance beam by first rapidly accelerating electrons at a high gradient during a short ({approx}1 ns), high-voltage pulse, and then injecting the electrons into an rf cavity for subsequent acceleration. Simulations show that significant improvement of the emittance appears when a high field ({approx} 0.5-1 GV/m) is applied to the cathode surface. An adjustable dc gap ({le} 1 mm) which can be integrated with an rf cavity is designed for initial testing at the Injector Test Stand at Argonne National Laboratory using an existing 70-kV pulse generator. Plans for additional experiments of an integrated dc/rf gun with a 250-kV pulse generator are being made.

  16. 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.

  17. A Digitally Implemented Photovoltaic Simulator with a Double Current Mode Controller

    E-Print Network [OSTI]

    Kimball, Jonathan W.

    -DC converter-based photovoltaic (PV) simulator which emulates the output characteristics of a real solar panel data and a double current mode controller that regulates output current is implemented. In particular, the PV simulator designed is portable and has a maximum output power of 85W. The control

  18. Analysis of dc harmonics using the three-pulse model for the intermountain power project HVDC transmission

    SciTech Connect (OSTI)

    Dickmander, D.L.; Peterson, K.J.

    1989-04-01T23:59:59.000Z

    The harmonic analysis of the dc-side of an HVDC line transmission requires realistic models of the converters, the dc line, and other relevant equipment. These models must include all important paths for harmonic current, and appropriate sources of harmonic voltage generation. The classical converter modeling technique has been demonstrated to be insufficient in field measurements and analysis of the harmonic spectra found on recent HVDC line transmission. For this reason, a new model of the converter bridge which takes into account the major stray capacitances in the converter (the three-pulse model) has been developed, and is described in detail elsewhere. This paper presents comparisons between the classical and three-pulse calculations for the Intermountain Power Project (IPP) HVDC transmission. The calculation results from the three-pulse model agree favorably with the harmonics found in field measurements.

  19. A Novel Inductor-less DC-AC Cascaded H-bridge Multilevel Boost Inverter for Electric/Hybrid Electric Vehicle Applications

    SciTech Connect (OSTI)

    Du, Zhong [ORNL; Ozpineci, Burak [ORNL; Tolbert, Leon M [ORNL; Chiasson, John N [ORNL

    2007-01-01T23:59:59.000Z

    This paper presents an inductorless cascaded H- bridge multilevel boost inverter for EV and HEV applications. Currently available power inverter systems for HEVs use a DC- DC boost converter to boost the battery voltage for a traditional 3-phase inverter. The present HEV traction drive inverters have low power density, are expensive, and have low efficiency because they need a bulky inductor. An inductorless cascaded H-bridge multilevel boost inverter for EV and HEV applications is proposed in this paper. Traditionally, each H-bridge needs a DC power supply. The proposed inductorless cascaded H-bridge multilevel boost inverter uses a standard 3-leg inverter (one leg for each phase) and an H-bridge in series with each inverter leg which uses a capacitor as the DC power source. Fundamental switching scheme is used to do modulation control and to produce a 5-level phase voltage. Experiments show that the proposed inductorless DC-AC cascaded H-bridge multilevel boost inverter can output a boosted AC voltage.

  20. ARQ.3.2002.dc/FINAL

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)Productssondeadjustsondeadjust DocumentationARMStreamsUS DepartmentARM'sARPES Provides Direct Evidence of

  1. Optimizing Energy Savings from Direct-DC in U.S. Residential Buildings

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01T23:59:59.000Z

    to the battery, and the percentage of excess PV power thatbattery charging capacity to excess PV. ..37], local battery storage for building-sited PV, if handled

  2. Optimizing Energy Savings from Direct-DC in U.S. Residential Buildings

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01T23:59:59.000Z

    Battery Backup (AC-House) ..Battery Backup (AC-House) .Inverter without Battery Backup (AC-House) Description Grid-

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

    E-Print Network [OSTI]

    Sulistyono, Widodo

    1994-01-01T23:59:59.000Z

    disadvantages of the conventional approach are: it requires relatively large input ac filter components, requires two stages of rectification and of de filtering (i.e., at the front-end and output rectifiers), and exhibit poor overall input power factor...

  4. Optimizing Energy Savings from Direct-DC in U.S. Residential Buildings

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01T23:59:59.000Z

    the market, in fact, the battery-storage inverter describedalong with 22 kWh of battery storage. This study by Baek etpower, but the cost of battery storage per unit of load

  5. Optimizing Energy Savings from Direct-DC in U.S. Residential Buildings

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01T23:59:59.000Z

    average residential electricity consumption by end-use inaverage residential electricity consumption by end-use inU.S. residential electricity consumption for 2010 for 32

  6. Optimizing Energy Savings from Direct-DC in U.S. Residential Buildings

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01T23:59:59.000Z

    Battery storage was included in both houses 3 . Battery efficiencybattery backup inverters on the market than there are non-storage inverters. Efficiencybattery storage. This study by Baek et al [17] claims only a modest 1.5-3% efficiency

  7. Interconnection of Direct-drive Wind Turbines Using A Series Connected DC Grid.

    E-Print Network [OSTI]

    Veilleux, Etienne

    2010-01-01T23:59:59.000Z

    ??This thesis presents the concept of a "distributed HVDC converter" for offshore wind farms. The proposed converter topology allows series interconnection of wind turbines obviating… (more)

  8. Optimizing Energy Savings from Direct-DC in U.S. Residential Buildings

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01T23:59:59.000Z

    52LPW assuming 80% incandescent @14LPW goes to CFL @52LPWthan the traditional incandescent lighting it is replacingbest technology Lighting Incandescent, fluorescent, LED

  9. A Five-Phase Brushless DC-Machine Direct Drive System EPE Journal Vol. 14 no

    E-Print Network [OSTI]

    Simões, Marcelo Godoy

    inverter control scheme and higher cost. Control complexity is easily managed with the new generation-leg inverter has been shown to be able to supply two three-phase induction motors; such power structure allows, their inverters, modeling and control. However, polyphase schemes have been used in the past in drive systems

  10. Optimizing Energy Savings from Direct-DC in U.S. Residential Buildings

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01T23:59:59.000Z

    wind turbines, and micro- hydro, PV dominates building-sitedgrid-integrated), 3% micro-hydro, and 2% micro-wind. Grid-

  11. Optimizing Energy Savings from Direct-DC in U.S. Residential Buildings

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01T23:59:59.000Z

    heat pump technologies where applicable models exist (electric water heaters,Heat Pumps for AC Electric Clothes Dryers Electric Secondary Space Heaters Dishwashers Electric Water Heaters (

  12. Solar Decathlon at Home in the D.C. Community | Department of...

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

    at Home in the D.C. Community Solar Decathlon at Home in the D.C. Community December 4, 2012 - 4:25pm Addthis One of the new homeowners, Layika Culley, and her family cut the...

  13. Analysis of Fe Nanoparticles Using XPS Measurements Under D.C...

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

    Fe Nanoparticles Using XPS Measurements Under D.C. or Pulsed-Voltage Bias. Analysis of Fe Nanoparticles Using XPS Measurements Under D.C. or Pulsed-Voltage Bias. Abstract: The...

  14. Energy Secretary Moniz's Remarks at CSIS in Washington D.C. on...

    Office of Environmental Management (EM)

    Energy Secretary Moniz's Remarks at CSIS in Washington D.C. on Energy Security 40 Years after the Embargo - As Delivered Energy Secretary Moniz's Remarks at CSIS in Washington D.C....

  15. D.C. Community Comes Together in the Name of Sustainability,...

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

    D.C. Community Comes Together in the Name of Sustainability, Affordability D.C. Community Comes Together in the Name of Sustainability, Affordability July 1, 2011 - 1:02pm Addthis...

  16. Train the Teacher - Energy Workshops for DC-area Elementary School...

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

    Train the Teacher - Energy Workshops for DC-area Elementary School Teachers Train the Teacher - Energy Workshops for DC-area Elementary School Teachers May 2, 2014 1:00PM to 4:15PM...

  17. Q&A: Kristen Psaki of WeatherizeDC | Department of Energy

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

    Q&A: Kristen Psaki of WeatherizeDC April 15, 2010 - 3:45pm Addthis Roughly 20 percent of carbon emissions come from inefficient homes. The DC Project says it has found a way to...

  18. Hybrid Multilevel Inverter with Single DC Haiwen Liu1

    E-Print Network [OSTI]

    Tolbert, Leon M.

    Hybrid Multilevel Inverter with Single DC Source Haiwen Liu1 , Leon M. Tolbert1, 2 , Burak Ozpineci Knoxville, TN 37932 3. Parker-Hannifin Corp. Olive Branch, MI 38654 Abstract- A hybrid multilevel inverter inverter (one leg for each phase) and H-bridge in series with each inverter leg. The inverter can be used

  19. DC Optimal Power Flow: Uniqueness and Chee Wei Tan

    E-Print Network [OSTI]

    Tan, Chee Wei

    and are computationally fast for practical smart power grids. I. BACKGROUND The Optimal Power Flow (OPF) problem network. The DC-OPF can be practically important in a smart grid, where there are renewables, e.g., solar implications on how algorithms can be designed to solve the OPF in a smart grid. Different from prior work

  20. Natural Gas Pipeline Leaks Across Washington, DC Robert B. Jackson,,,

    E-Print Network [OSTI]

    Jackson, Robert B.

    Natural Gas Pipeline Leaks Across Washington, DC Robert B. Jackson,,, * Adrian Down, Nathan G increased in recent decades, but incidents involving natural gas pipelines still cause an average of 17 fatalities and $133 M in property damage annually. Natural gas leaks are also the largest anthropogenic

  1. D.C. Water Resources Research Institute Annual Technical Report

    E-Print Network [OSTI]

    projects that address the three components of integrated urban water system: storm water runoff and sewer developing and maintaining new environmental quality testing and modeling tools to advance water researchD.C. Water Resources Research Institute Annual Technical Report FY 2013 D.C. Water Resources

  2. Electrostatic coalescence system with independent AC and DC hydrophilic electrodes

    DOE Patents [OSTI]

    Hovarongkura, A. David (Arlington, VA); Henry, Jr., Joseph D. (Morgantown, WV)

    1981-01-01T23:59:59.000Z

    An improved electrostatic coalescence system is provided in which independent AC and DC hydrophilic electrodes are employed to provide more complete dehydration of an oil emulsion. The AC field is produced between an AC electrode array and the water-oil interface wherein the AC electrode array is positioned parallel to the interface which acts as a grounded electrode. The emulsion is introduced into the AC field in an evenly distributed manner at the interface. The AC field promotes drop-drop and drop-interface coalescence of the water phase in the entering emulsion. The continuous oil phase passes upward through the perforated AC electrode array and enters a strong DC field produced between closely spaced DC electrodes in which small dispersed droplets of water entrained in the continuous phase are removed primarily by collection at hydrophilic DC electrodes. Large droplets of water collected by the electrodes migrate downward through the AC electrode array to the interface. All phase separation mechanisms are utilized to accomplish more complete phase separation.

  3. High Voltage DC Transmission 1.0 Introduction

    E-Print Network [OSTI]

    McCalley, James D.

    1 High Voltage DC Transmission 1.0 Introduction HVDC has been applied in electric power systems for many years now. Figure 1 illustrates worldwide many of the HVDC applications [1]. Fig. 1 ABB provides a webpage which summarizes HVDC projects by type and capacity or by commissioning year [2]. Wikipedia [3

  4. High Voltage DC Transmission 2 1.0 Introduction

    E-Print Network [OSTI]

    McCalley, James D.

    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

  5. Electromagnetic Coupling in a dc Motor and Tachometer Assembly

    E-Print Network [OSTI]

    Awtar, Shorya

    -pole permanent magnet stator devices. A shaft of finite stiffness connects the tachometer and motor armatures machines. The experimental test setup consists of an integrated permanent magnet dc motor-tachometer unit-tachometer shaft or a flexible mechanical coupling, this exercise in servo-control design becomes quite challenging

  6. Building Scale DC Microgrids Chris Marnay, Steven Lanzisera, Michael Stadler, and Judy Lai

    E-Print Network [OSTI]

    of building loads are either native DC, such as electronics and compact fluorescent and light emitting diode

  7. Interviews in Washington, DC for Albert Einstein Fellowship Semi-Finalists

    Broader source: Energy.gov [DOE]

    Selected semi-finalists in the Albert Einstein Distinguished Educator Fellowship are invited to DC for interviews.

  8. Analysis of WACSIS data using a directional hybrid wave model

    E-Print Network [OSTI]

    Zhang, Shaosong

    2007-04-25T23:59:59.000Z

    .1 Backgrounds.........................................................................................1 1.2 Objectives.............................................................................................5 II DIRECTIONAL HYBRID WAVE MODEL... ......................................................................41 V ANALYSIS OF DIRECTIONAL WAVE FIELDS WITH STRONG CURRENT ...............................................................................................45 5.1 Introduction...

  9. November 2002 15th TOFE, Washington, D.C. 1 Thermal Behavior and Operating

    E-Print Network [OSTI]

    Raffray, A. René

    November 2002 15th TOFE, Washington, D.C. 1 Thermal Behavior and Operating Requirements of IFE Washington, D.C. November 2002 #12;November 2002 15th TOFE, Washington, D.C. 2 Abstract During injection the thermal behavior of the target under such conditions and explores possible ways of extending the target

  10. On the optimization of a dc arcjet diamond chemical vapor deposition reactor

    E-Print Network [OSTI]

    Dandy, David

    On the optimization of a dc arcjet diamond chemical vapor deposition reactor S. W. Reevea) and W. A precursor in our dc arcjet reactor.1 Based on conclusions drawn from that work, an optimization strategy diamond film growth in a dc arcjet chemical vapor deposition reactor has been developed. Introducing

  11. Current balancing for battery strings

    DOE Patents [OSTI]

    Galloway, James H. (New Baltimore, MI)

    1985-01-01T23:59:59.000Z

    A battery plant is described which features magnetic circuit means for balancing the electrical current flow through a pluraliircuitbattery strings which are connected electrically in parallel. The magnetic circuit means is associated with the battery strings such that the conductors carrying the electrical current flow through each of the battery strings pass through the magnetic circuit means in directions which cause the electromagnetic fields of at least one predetermined pair of the conductors to oppose each other. In an alternative embodiment, a low voltage converter is associated with each of the battery strings for balancing the electrical current flow through the battery strings.

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

    E-Print Network [OSTI]

    Cañizares, Claudio A.

    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

  13. Alternating current long range alpha particle detector

    DOE Patents [OSTI]

    MacArthur, D.W.; McAtee, J.L.

    1993-02-16T23:59:59.000Z

    An alpha particle detector, utilizing alternating currents, which is capable of detecting alpha particles from distinct sources. The use of alternating currents allows use of simpler ac circuits which, in turn, are not susceptible to dc error components. It also allows the benefit of gas gain, if desired. In the invention, a voltage source creates an electric field between two conductive grids, and between the grids and a conductive enclosure. Air containing air ions created by collision with alpha particles is drawn into the enclosure and detected. In some embodiments, the air flow into the enclosure is interrupted, creating an alternating flow of ions. In another embodiment, a modulated voltage is applied to the grid, also modulating the detection of ions.

  14. Multilevel cascade voltage source inverter with seperate DC sources

    DOE Patents [OSTI]

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

    1997-01-01T23:59:59.000Z

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

  15. Multilevel cascade voltage source inverter with separate DC sources

    DOE Patents [OSTI]

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

    1997-06-24T23:59:59.000Z

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

  16. Multilevel cascade voltage source inverter with seperate DC sources

    DOE Patents [OSTI]

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

    2002-01-01T23:59:59.000Z

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

  17. Report on Non-Contact DC Electric Field Sensors

    SciTech Connect (OSTI)

    Miles, R; Bond, T; Meyer, G

    2009-06-16T23:59:59.000Z

    This document reports on methods used to measure DC electrostatic fields in the range of 100 to 4000 V/m using a non-contact method. The project for which this report is written requires this capability. Non-contact measurements of DC fields is complicated by the effect of the accumulation of random space-charges near the sensors which interfere with the measurement of the field-of-interest and consequently, many forms of field measurements are either limited to AC measurements or use oscillating devices to create pseudo-AC fields. The intent of this document is to report on methods discussed in the literature for non-contact measurement of DC fields. Electric field meters report either the electric field expressed in volts per distance or the voltage measured with respect to a ground reference. Common commercial applications for measuring static (DC) electric fields include measurement of surface charge on materials near electronic equipment to prevent arcing which can destroy sensitive electronic components, measurement of the potential for lightning to strike buildings or other exposed assets, measurement of the electric fields under power lines to investigate potential health risks from exposure to EM fields and measurement of fields emanating from the brain for brain diagnostic purposes. Companies that make electric field sensors include Trek (Medina, NY), MKS Instruments, Boltek, Campbell Systems, Mission Instruments, Monroe Electronics, AlphaLab, Inc. and others. In addition to commercial vendors, there are research activities continuing in the MEMS and optical arenas to make compact devices using the principles applied to the larger commercial sensors.

  18. !#"%$'&)(02130546708913@A4B0DC Scott Schaefer, Joe Warren

    E-Print Network [OSTI]

    Warren, Joe

    ¢¡¤£¦¥¨§©©¡ !#"%$'&)(¤02130546708913£@¡A4B0DC Scott Schaefer, Joe Warren Rice UniversityE: for each edge in the grid that contains a sign change (i.e.; the vertices on its end- points these methods primal methods. i e-mail: p sschaefe,jwarrenq @rice.edu Figure 1: A sphere contoured using

  19. DC Resistivity Survey (Pole-Dipole Array) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of InspectorConcentratingRenewable Solutions LLC JumpCrow Lake Wind JumpCuttings AnalysisDC Resistivity

  20. Data:Dbdad3b1-04dc-40cd-843e-921faaade910 | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Pagec-01b596aa1744 No revisionDbdad3b1-04dc-40cd-843e-921faaade910 No revision has been approved for this page. It is currently

  1. New leading/trailing edge modulation strategies for two-stage AC/DC PFC adapters to reduce DC-link capacitor ripple current

    E-Print Network [OSTI]

    Sun, Jing

    2007-09-17T23:59:59.000Z

    -link capacitor is one of the largest because it should keep the output voltage with low ripple. Also, the size of this capacitor is penalized due to the universal line voltage application. Synchronization through employing leading edge modulation for the first...

  2. Optimal Demand Response in DC Distribution Networks Hamed Mohsenian-Rad, Member, IEEE and Ali Davoudi, Member, IEEE

    E-Print Network [OSTI]

    Mohsenian-Rad, Hamed

    such as photovoltaic systems are essentially DC sources. Battery storage devices are also easier H. Mohsenian

  3. Communication accepte: Healthy Buildings/IAQ'97 Washington DC, septembre 1997Communication accepte: Healthy Buildings/IAQ'97 Washington DC, septembre 1997 DISCRIMINATION OF VOLATILE ORGANIC COMPOUNDS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Communication acceptée: Healthy Buildings/IAQ'97 Washington DC, septembre 1997Communication acceptée: Healthy Buildings/IAQ'97 Washington DC, septembre 1997 DISCRIMINATION OF VOLATILE ORGANIC manuscript, published in "4th International Conference on Healthy Buildings'97, Washington : United States

  4. Design and analysis of multiphase DC-DC converters with coupled inductors

    E-Print Network [OSTI]

    Shi, Meng

    2007-09-17T23:59:59.000Z

    (1 4)( 2-3 ) ( || )short k m kL with shorted L L L- = + (5) If Lm>>Lk, then (1 4) 2short kL L- = (6) This is measurement is often used to measure the leakage... inductance in transformer applications because it is assumed that Lm>>Lk. However, for the coupled inductor, this is not the case, and as such Lshort does not lead to a clear or direct measurement of the leakage inductance. A better measurement...

  5. To cite this document: GOIFFON Vincent, VIRMONTOIS Cdric, MAGNAN Pierre. Investigation of dark current random telegraph signal in pinned photodiode CMOS image

    E-Print Network [OSTI]

    Mailhes, Corinne

    current random telegraph signal in pinned photodiode CMOS image sensors. In: IEEE International Electron Current Random Telegraph Signal in Pinned Photodiode CMOS Image Sensors Vincent Goiffon, Cédric Virmontois The characteristics of Dark Current Random Telegraph Signal (DC-RTS), observed in Pinned PhotoDiode (PPD) CMOS Image

  6. High-brightness, high-current ion sources

    SciTech Connect (OSTI)

    Keller, R.

    1985-01-01T23:59:59.000Z

    Several existing high-current dc ion sources are presented that yield positive ions and are based on gas discharges. Their common features are then outlined: extraction systems, required plasma qualities, and the production of ions from solid materials. Finally, from well-established laws, scaling rules for high-brightness ion beams are derived taking one specific case to determine the numerical constants. These rules predict that the current values of transportable beams scale proportionally to the 3/2 power of the extraction voltage, whereas the brightness strongly decreases with rising voltage.

  7. High-current, fast-switching transistor development

    SciTech Connect (OSTI)

    Hower, P.L.

    1981-03-15T23:59:59.000Z

    Work that shows how the results obtained under a previous contract (NAS3-18916) have been applied to a larger-diameter (33-mm) transistor are described. An improved base contact for equalizing the base-emitter voltage at high currents has been developed along with an improved emitter contact preform which increases the silicon area available for current conduction. The electrical performance achieved is consistent with the proposed optimum design. The device design, wafer-processing techniques, and various measurements which include forward SOA, dc characteristics, and switching times are described.

  8. Current Directions in Psychological 20(6) 400406

    E-Print Network [OSTI]

    Barrett, Lisa Feldman

    and permission: sagepub.com/journalsPermissions.nav DOI: 10.1177/0963721411429125 http://cdps.sagepub.com Charles, wide-eyed expression) evolved to express certain internal mental states (e.g., fear) and that humans scien- tific papers casually state that expressions are innate and uni- versally recognized. Research

  9. http://cdp.sagepub.com/ Current Directions in Psychological

    E-Print Network [OSTI]

    A Window on Reality : Perceiving Edited Moving Images Published by: http the cognitive and perceptual bases of film has been a lonely activity. Near the inception of film, some astute to understand film. Part of the reason for this lack of interest has been the presumption that the discontinuous

  10. Direct-Current Resistivity Survey At Lightning Dock Area (Warpinski...

    Open Energy Info (EERE)

    Survey Activity Date Usefulness not indicated DOE-funding Unknown Notes As a foundation for successful siting and drilling a deep test well, additional geophysical work has...

  11. Direct-Current Resistivity Survey At Cove Fort Area - Vapor ...

    Open Energy Info (EERE)

    Notes Update to Warpinski, et al., 2002 References N. R. Warpinski, A. R. Sattler, R. Fortuna, D. A. Sanchez, J. Nathwani (2004) Geothermal Resource Exploration And Definition...

  12. Direct-Current Resistivity Survey At Cove Fort Area (Warpinski...

    Open Energy Info (EERE)

    Notes Update to Warpinski, et al., 2002 References N. R. Warpinski, A. R. Sattler, R. Fortuna, D. A. Sanchez, J. Nathwani (2004) Geothermal Resource Exploration And Definition...

  13. Direct-Current Resistivity Survey At Mt Princeton Hot Springs...

    Open Energy Info (EERE)

    Survey Activity Date 2010 Usefulness useful DOE-funding Unknown Notes Used to map fracture and fluid flow patterns. References K. Richards, A. Revil, A. Jardani, F. Henderson,...

  14. Direct-Current Resistivity Survey At Long Valley Caldera Geothermal...

    Open Energy Info (EERE)

    conductive regions here may be caused by hydrothermal alteration or a fluid filled fracture system." References Daniel F. C. Pribnow, Claudia Schutze, Suzanne J. Hurter,...

  15. Direct-Current Resistivity At Central Nevada Seismic Zone Region...

    Open Energy Info (EERE)

    Activity Date Usefulness useful DOE-funding Unknown Notes NOTE: These are theoreticalcomputer simulation tests of various methods on eight hypothetical 'model' basing-and-range...

  16. Direct-Current Resistivity Survey At Valles Caldera - Redondo...

    Open Energy Info (EERE)

    structure in the reservoir region. Some of the data were reinterpreted using K508 computer models, and interpretations from the various surveys were compared for consistency of...

  17. Direct-Current Resistivity Survey At Walker-Lane Transitional...

    Open Energy Info (EERE)

    Activity Date Usefulness useful DOE-funding Unknown Notes NOTE: These are theoreticalcomputer simulation tests of various methods on eight hypothetical 'model' basing-and-range...

  18. Direct-Current Resistivity Survey At Northern Basin & Range Region...

    Open Energy Info (EERE)

    Activity Date Usefulness useful DOE-funding Unknown Notes NOTE: These are theoreticalcomputer simulation tests of various methods on eight hypothetical 'model' basing-and-range...

  19. Direct-Current Resistivity Survey At Nw Basin & Range Region...

    Open Energy Info (EERE)

    Activity Date Usefulness useful DOE-funding Unknown Notes NOTE: These are theoreticalcomputer simulation tests of various methods on eight hypothetical 'model' basing-and-range...

  20. Direct-Current Resistivity Survey At Central Nevada Seismic Zone...

    Open Energy Info (EERE)

    Activity Date Usefulness useful DOE-funding Unknown Notes NOTE: These are theoreticalcomputer simulation tests of various methods on eight hypothetical 'model' basing-and-range...

  1. Direct-Current Resistivity Survey At Lightning Dock Area (Cunniff...

    Open Energy Info (EERE)

    traverse, but was offset northward more than 500 feet to avoid the producing geothermal wells and other manmade cultural effects in the area. The locations for these two...

  2. Direct-Current Resistivity Survey At Blue Mountain Area (Fairbank

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublic Utilities Address:011-DNA Jump to:52c8ff988c1Dering Harbor, NewRidge,Dinwiddie County,|Open

  3. Direct-Current Resistivity Survey At Valles Caldera - Redondo Geothermal

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublic Utilities Address:011-DNA Jump to:52c8ff988c1Dering Harbor, NewRidge,Dinwiddie(FURUMOTO,Open Energy2006)Area

  4. Direct-Current Resistivity Survey At Valles Caldera - Sulphur Springs

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublic Utilities Address:011-DNA Jump to:52c8ff988c1Dering Harbor, NewRidge,Dinwiddie(FURUMOTO,Open

  5. Current Delegations by Functional Area - DOE Directives, Delegations, and

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-Series to UserProduct: Crude OilPublic Safety and ResourceTRANSCOM

  6. Current Delegations by Position - DOE Directives, Delegations, and

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-Series to UserProduct: Crude OilPublic Safety and

  7. Sandia National Laboratories: temporal variation of current direction

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1developmentturbineredox-activeNational SolartSSL George Wang's

  8. Direct-Current Resistivity At Central Nevada Seismic Zone Region

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revision has beenFfe2fb55-352f-473b-a2dd-50ae8b27f0a6 No revision has Type Term TitleSilverDillon Wind(Pritchett,

  9. Direct-Current Resistivity Survey | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revision has beenFfe2fb55-352f-473b-a2dd-50ae8b27f0a6 No revision has Type TermOpen EnergyEnergy2002)Open Jump to:

  10. DIRECT-DRIVE AND EDDY-CURRENT SEPTUM MAGNETS

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed Newcatalyst phases onOrganization FY Middle School

  11. Category:Direct-Current Resistivity Survey | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublic Utilities Address: 160Benin: EnergyBostonFacilityCascade SierraStatus Statuspage? For detailed information

  12. Direct-Current Resistivity Survey At Mauna Loa Southwest Rift...

    Open Energy Info (EERE)

    not indicated DOE-funding Unknown Notes Field surveys in the South Point area were limited to a series of Schlumberger soundings and a self-potential traverse across the...

  13. Increasing the CO tolerance of PEM fuel cells via current pulsing and self-oxidation

    E-Print Network [OSTI]

    Thomason, Arthur Hugh

    2004-09-30T23:59:59.000Z

    operation was 1.0 A/cm2, 0.25 Hz, and a 5% duty cycle. A pulse (120 Hz, 50% duty cycle) similar to the ripple current often generated when converting DC to single-phase 60 Hz AC had a positive effect on the CO tolerance of the system, but at frequencies...

  14. Electrospray Diagnostics by Fourier Analysis of Current Oscillations and Fast Imaging

    E-Print Network [OSTI]

    Vertes, Akos

    Electrospray Diagnostics by Fourier Analysis of Current Oscillations and Fast Imaging Lida Parvin of the spray voltage, liquid flow rate, and composition. Most Fourier spectra indicated a strong dc component, a low-frequency branch at low flow rates and applied voltages, and a high- frequency branch

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

    SciTech Connect (OSTI)

    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

    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)

  16. The dc modeling program (DCMP): Version 2. 0

    SciTech Connect (OSTI)

    Chapman, D.G. (Manitoba HVDC Research Centre, Winnipeg, MB (Canada))

    1990-08-01T23:59:59.000Z

    In this project one of the main objectives was the refinement of tools for the study of HVDC systems. The original software was prepared in project RP1964-2 (EL-4365) as power flow and stability program models for HVDC systems. In this project new modeling capabilities were added to both the power flow and stability models. Additionally, the HVDC specific model capabilities were integrated into a new program, termed the Standalone program, for use in the development and testing of HVDC models. This manual provides technical background for programmers and those interested in understanding, augmenting or transporting the dc models.

  17. Positron lifetime spectrometer using a DC positron beam

    DOE Patents [OSTI]

    Xu, Jun; Moxom, Jeremy

    2003-10-21T23:59:59.000Z

    An entrance grid is positioned in the incident beam path of a DC beam positron lifetime spectrometer. The electrical potential difference between the sample and the entrance grid provides simultaneous acceleration of both the primary positrons and the secondary electrons. The result is a reduction in the time spread induced by the energy distribution of the secondary electrons. In addition, the sample, sample holder, entrance grid, and entrance face of the multichannel plate electron detector assembly are made parallel to each other, and are arranged at a tilt angle to the axis of the positron beam to effectively separate the path of the secondary electrons from the path of the incident positrons.

  18. EA-351 DC Energy Dakota, LLC | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:Year in Review: TopEnergy DOEDealingVehicle1 Closing American Electric0-A S.A.C.94-A-B1 DC

  19. Hardwired Control Changes For NSTX DC Power Feeds

    SciTech Connect (OSTI)

    Ramakrishnan, S.

    2013-06-28T23:59:59.000Z

    The National Spherical Torus Experiment (NSTX) has been designed and installed in the existing facilities at Princeton Plasma Physics Laboratory (PPPL). Most of the hardware, plant facilities, auxiliary sub-systems, and power systems originally used for the Tokamak Fusion Test Reactor (TFTR) have been used with suitable modifications to reflect NSTX needs. The original TFTR Hardwired Control System (HCS) with electromechanical relays was used for NSTX DC Power loop control and protection during NSTX operations. As part of the NSTX Upgrade, the HCS is being changed to a PLC-based system with the same control logic. This paper gives a description of the changeover to the new PLC-based system __________________________________________________

  20. Energy Incentive Programs, Washington DC | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:Year in Review: TopEnergyIDIQBusinessin Jamaica,Idaho EnergyMontanaOregonTexasWashington DC

  1. DC Resistivity Survey (Dipole-Dipole Array) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of InspectorConcentratingRenewable Solutions LLC JumpCrow Lake Wind JumpCuttings AnalysisDC Resistivity Survey

  2. DC Resistivity Survey (Schlumberger Array) At Coso Geothermal Area (1977) |

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of InspectorConcentratingRenewable Solutions LLC JumpCrow Lake Wind JumpCuttings AnalysisDC ResistivityOpen

  3. DC Resistivity Survey (Wenner Array) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of InspectorConcentratingRenewable Solutions LLC JumpCrow Lake Wind JumpCuttings AnalysisDC ResistivityOpen Jump

  4. Three-wire magnetic trap for direct forced evaporative cooling Shengwang Du1,* and Eun Oh2

    E-Print Network [OSTI]

    Du, Shengwang

    Three-wire magnetic trap for direct forced evaporative cooling Shengwang Du1,* and Eun Oh2 1 Kong, China 2 U.S. Naval Research Laboratory, Remote Sensing Division, Washington, D.C. 20375, USA potential for direct forced evaporative cooling of neutral atoms without using induced spin

  5. An Introduction to Wave-Current Interactions

    E-Print Network [OSTI]

    Smith, Jerome A.

    -scale wave focusing across a storm can re-direct the wind-stress? #12;1. Adiabatic interaction StartAn Introduction to Wave-Current Interactions Jerry Smith, MPL-SIO-UCSD jasmith@ucsd.edu http just want to hold up your hand. #12;Some Questions in Wave-Current Interaction Physics 1. Adiabatic

  6. E-Print Network 3.0 - ac-dc power transmission Sample Search...

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

    Ris Summary: (AEDVESESY) DFIG control Power control loop Speed control loop Wind turbine control Measurement grid point AC DC... reference DFIG control Power control...

  7. Design and Modeling of Centralized Distribution Network for the DC House Project.

    E-Print Network [OSTI]

    Bassi, Harpreet S.

    2013-01-01T23:59:59.000Z

    ?? This thesis focuses on the design, modeling, simulation, and performance evaluation of Centralized Distribution Network for the DC House Project. Power System Computer Aided… (more)

  8. Integrated Solar Power Converters: Wafer-Level Sub-Module Integrated DC/DC Converter

    SciTech Connect (OSTI)

    None

    2012-02-09T23:59:59.000Z

    Solar ADEPT Project: CU-Boulder is developing advanced power conversion components that can be integrated into individual solar panels to improve energy yields. The solar energy that is absorbed and collected by a solar panel is converted into useable energy for the grid through an electronic component called an inverter. Many large, conventional solar energy systems use one, central inverter to convert energy. CU-Boulder is integrating smaller, microinverters into individual solar panels to improve the efficiency of energy collection. The University’s microinverters rely on electrical components that direct energy at high speeds and ensure that minimal energy is lost during the conversion process—improving the overall efficiency of the power conversion process. CU-Boulder is designing its power conversion devices for use on any type of solar panel.

  9. Directives Help - DOE Directives, Delegations, and Requirements

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

    Directives Help by Website Administrator All DOE directives are available through this site. While it may seem overwhelming, given the number of documents, we have provided a...

  10. Design and analysis of a zero-voltage switching scheme for a dc- to-dc converter

    E-Print Network [OSTI]

    Arun, G.

    1992-01-01T23:59:59.000Z

    &rt~RV, Page 40 Voltage across inain switch in a clc cliopper clrive with zeio-voltage s w 1 't C 1 1 i l1 g , &g CHAPTER I INTRODUCTION A. Introduction In general terms, power electronics is concerned wit, h the conversion and control of electrical... power (dc or ac) at variable voltage and variable frequency. With the development of power semi- conductor devices such as silicon-controlled rectifiers (SCR's), gate-turn-off thyris- tors (GTO's), bipolar junction transistors (BJT's), metal...

  11. Data:Eec988f9-dc0d-45ef-9789-a7781dc1934b | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Pagec-01b596aa1744b55997c1ccEeae2669-ec94-4cc4-bbae-0108084310cc No revision has been approved for this81dc1934b No revision

  12. Waste form development for a DC arc furnace

    SciTech Connect (OSTI)

    Feng, X.; Bloomer, P.E.; Chantaraprachoom, N.; Gong, M.; Lamar, D.A.

    1996-09-01T23:59:59.000Z

    A laboratory crucible study was conducted to develop waste forms to treat nonradioactive simulated {sup 238}Pu heterogeneous debris waste from Savannah River, metal waste from the Idaho National Engineering Laboratory (INEL), and nominal waste also from INEL using DC arc melting. The preliminary results showed that the different waste form compositions had vastly different responses for each processing effect. The reducing condition of DC arc melting had no significant effects on the durability of some waste forms while it decreased the waste form durability from 300 to 700% for other waste forms, which resulted in the failure of some TCLP tests. The right formulations of waste can benefit from devitrification and showed an increase in durability by 40%. Some formulations showed no devitrification effects while others decreased durability by 200%. Increased waste loading also affected waste form behavior, decreasing durability for one waste, increasing durability by 240% for another, and showing no effect for the third waste. All of these responses to the processing and composition variations were dictated by the fundamental glass chemistry and can be adjusted to achieve maximal waste loading, acceptable durability, and desired processing characteristics if each waste formulation is designed for the result according to the glass chemistry.

  13. Naval Research Laboratory Washington, DC 20375-5320

    E-Print Network [OSTI]

    Arlington, VA 22217 11. SUPPLEMENTARY NOTES *Currently with Booz Allen Hamilton National Security Team, Mc

  14. Curvature and torsion effects in electric current-carrying twisted solar loops

    SciTech Connect (OSTI)

    Garcia de Andrade, L. C. [Departamento de Fisica Teorica-IF-UERJ, Rua Sao Francisco Xavier 524, Rio de Janeiro, RJ Maracana, CEP 20550-013 Brazil (Brazil)

    2006-11-15T23:59:59.000Z

    Riemannian geometry of the electric current-carrying solar loops is obtained from a thin tube approximation of twisted magnetic flux tubes. The Frenet torsion and curvature affect the electron drift speed of the electrons of the current along the toroidal direction of the tube. The twist of the tube is computed and it is shown that twist is maximum at the surface of the tube and minimum at the tube axis. This acts as inertia effects to the electron drift. The higher the torsion of the tube axis the smaller is the velocity along the direction of the tube. This effect is similar to the one obtained by Tyspin et al. [Physics of Plasmas, 5, 3385 (1998)] in the case of toroidal devices with curvature and torsion. Here the simple geometrical effects are enough to slow down the currents and no viscosity in the fluid is taken into account. A slight compressibility of the plasma flow is due to the twist of the tube. As applications of these ideas, it is shown that torsion effects are not enough to accelerate electrons up to relativistic energies, and the torsion is computed in the case of the force-free loop. The value of torsion is used to compute the electron acceleration in two distinct cases. The first is the case when the Riemann loop suffers the action of a dc electric sub-Dreicer field, where the magnetic field is direct along the magnetic loop, and the loop moves along the orthogonal direction to the loop as in vortex filaments. In this case, the acceleration is shown to be of the order of 10{sup -17} cm s{sup -2} for a solar torsion of the order of 10{sup -4} cm{sup -1}. The second case is for the curvature drift contribution, where torsion is also present. In this case we show that torsion is not present in the velocity drift but just in the electron acceleration. Though these values are extremely low, they can be improved by considering small loops lowering the radius of the loop which, here, was taken as 600 km. Curvature drift acceleration is also estimated as 100 cm s{sup -2}.

  15. Compiler-Directed Region-Based Security for Low-Overhead Software Vijay Kongubangaram

    E-Print Network [OSTI]

    Simha, Rahul

    Compiler-Directed Region-Based Security for Low-Overhead Software Protection Vijay Kongubangaram Department of Computer Science The George Washington University Washington, DC vijaykpk@gwu.edu Olga Gelbart@gwu.edu Abstract Software security has become a prominent area of re- search in recent years, with research efforts

  16. Directions to the National Radio Astronomy Observatory Green Bank, West Virginia

    E-Print Network [OSTI]

    Groppi, Christopher

    Directions to the National Radio Astronomy Observatory Green Bank, West Virginia From Charleston Roanoke, VA: Via I-64 West, exit at White Sulphur Springs (Exit 181) and take Rt. 92 North to Green Bank, then take Rt. 92 South to Green Bank. From Washington DC: Via I-66 West to I-81 South. Option 1: Take I-81

  17. The Evolution of Sustainable Personal Vehicles

    E-Print Network [OSTI]

    Jungers, Bryan D

    2009-01-01T23:59:59.000Z

    carbon dioxide emissions CPE- criteria pollutant emissions DC- direct current DSM- demand-side management EESD- electrochemical energy storage

  18. Control of Parallel-Connected Bidirectional AC-DC Converters in Stationary Frame for Microgrid

    E-Print Network [OSTI]

    Teodorescu, Remus

    Control of Parallel-Connected Bidirectional AC-DC Converters in Stationary Frame for Microgrid-- With the penetration of renewable energy in modern power system, microgrid has become a popular application worldwide. In this paper, parallel-connected bidirectional converters for AC and DC hybrid microgrid application

  19. High Dynamic Performance Programmed PWM Control of a Multilevel Inverter with Capacitor DC Sources

    E-Print Network [OSTI]

    Tolbert, Leon M.

    High Dynamic Performance Programmed PWM Control of a Multilevel Inverter with Capacitor DC Sources inverter consisting of a stan- dard 3-leg inverter supplied by a DC source and three full H-bridges each reactive voltage to the motor while the standard three leg inverter can supply both reactive and active

  20. CTMCONTROL: Addressing the MC/DC Objective for Safety-Critical Automotive Software

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    CTMCONTROL: Addressing the MC/DC Objective for Safety-Critical Automotive Software Anila Mjeda.mjeda,mike.hinchey}@lero.ie Abstract. We propose a method tailored to the requirements of safety-critical embedded automotive software/DC) objective for automotive safety-critical software. CTMCONTROL is validated via a controlled experiment which

  1. Supervisory Control of an Adaptive-Droop Regulated DC Microgrid with Battery Management

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    such as photovoltaic (PV) systems and secondary batteries. In this paper, several distributed generators (DGs) have1 Supervisory Control of an Adaptive-Droop Regulated DC Microgrid with Battery Management been merged together with a pair of batteries and loads to form an autonomous dc Microgrid (MG

  2. PID Control with Derivative Filtering Integral Anti-Windup for a DC Servo

    E-Print Network [OSTI]

    PID Control with Derivative Filtering and Integral Anti-Windup for a DC Servo Nicanor Quijano in the prelab for PID controllers. For that, we use the DC motor for the SRV-02ET to do position control. You . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 2.4 PID Controller with Derivative Filtering

  3. DC H2O: What's on Tap? Annual Progress Report for FY 2004

    E-Print Network [OSTI]

    District of Columbia, University of the

    for distributing treated water to DC residents has taken the brunt of the blame and has developed mechanisms. Project resources have secured a GPS unit and additional resources have already been allocated for GIS as a part of the 4-H Youth Cyber Camp. And as such, will incorporate the technological aspects of the DC H2O

  4. Smith, D.C., et al., 2000 ODP Technical Note 28

    E-Print Network [OSTI]

    Smith, D.C., et al., 2000 ODP Technical Note 28 METHODS FOR QUANTIFYING POTENTIAL MICROBIAL CONTAMINATION DURING DEEP OCEAN CORING 1,2 David C. Smith,3 Arthur J. Spivack,4 Martin R. Fisk,5 Shelley A that these contamination tests be routinely conducted when coring for microbiological studies. 1Smith, D.C., Spivack, A

  5. A nonlinear robust HVDC control for a parallel AC/DC power system

    E-Print Network [OSTI]

    Qu, Zhihua

    A nonlinear robust HVDC control for a parallel AC/DC power system Hongzhi Cai a , Zhihua Qu b. Keywords: Robust control; HVDC; Power system; Stability; Lyapunov method 1. Introduction It has been recognized that, through an HVDC transmission line, fast electronic control can be applied on the DC power

  6. Federal Government Congressional Budget Office, Health & Human Services, Long Term Modeling Washington, DC

    E-Print Network [OSTI]

    Shyy, Wei

    Manila, Philippines BRAC Dhaka, Bangladesh California Forward San Francisco, CA CARE (WDI) Atlanta, GA and Dhaka, Bangladesh CARE USA Washington, DC SUMMER 2009 INTERNSHIPS #12;Center for Women Policy Studies Educational Resources Africa Kumasi, Ghana Pew Center on Global Climate Change Washington, DC Rick Snyder

  7. Adaptive Selective Harmonic Minimization Based on ANNs for Cascade Multilevel Inverters With Varying DC Sources

    SciTech Connect (OSTI)

    Filho, Faete [ORNL; Maia, Helder Z [UFMS, Department of Electrical Engineering; Mateus, Tiago Henrique D [ORNL; Ozpineci, Burak [ORNL; Tolbert, Leon M [ORNL; Pinto, Joao Onofre P [ORNL

    2013-01-01T23:59:59.000Z

    A new approach for modulation of an 11-level cascade multilevel inverter using selective harmonic elimination is presented in this paper. The dc sources feeding the multilevel inverter are considered to be varying in time, and the switching angles are adapted to the dc source variation. This method uses genetic algorithms to obtain switching angles offline for different dc source values. Then, artificial neural networks are used to determine the switching angles that correspond to the real-time values of the dc sources for each phase. This implies that each one of the dc sources of this topology can have different values at any time, but the output fundamental voltage will stay constant and the harmonic content will still meet the specifications. The modulating switching angles are updated at each cycle of the output fundamental voltage. This paper gives details on the method in addition to simulation and experimental results.

  8. Magnetic force microscopy method and apparatus to detect and image currents in integrated circuits

    DOE Patents [OSTI]

    Campbell, Ann. N. (13170-B Central SE #188, Albuquerque, NM 87123); Anderson, Richard E. (2800 Tennessee NE, Albuquerque, NM 87110); Cole, Jr., Edward I. (2116 White Cloud NE, Albuquerque, NM 87112)

    1995-01-01T23:59:59.000Z

    A magnetic force microscopy method and improved magnetic tip for detecting and quantifying internal magnetic fields resulting from current of integrated circuits. Detection of the current is used for failure analysis, design verification, and model validation. The interaction of the current on the integrated chip with a magnetic field can be detected using a cantilevered magnetic tip. Enhanced sensitivity for both ac and dc current and voltage detection is achieved with voltage by an ac coupling or a heterodyne technique. The techniques can be used to extract information from analog circuits.

  9. Magnetic force microscopy method and apparatus to detect and image currents in integrated circuits

    DOE Patents [OSTI]

    Campbell, A.N.; Anderson, R.E.; Cole, E.I. Jr.

    1995-11-07T23:59:59.000Z

    A magnetic force microscopy method and improved magnetic tip for detecting and quantifying internal magnetic fields resulting from current of integrated circuits are disclosed. Detection of the current is used for failure analysis, design verification, and model validation. The interaction of the current on the integrated chip with a magnetic field can be detected using a cantilevered magnetic tip. Enhanced sensitivity for both ac and dc current and voltage detection is achieved with voltage by an ac coupling or a heterodyne technique. The techniques can be used to extract information from analog circuits. 17 figs.

  10. Departmental Directives Program

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

    2006-08-16T23:59:59.000Z

    The Order is the primary directive for administering the Department's directives Program. Cancels: DOE O 251.1A

  11. FLUXCAP: A flux-coupled ac/dc magnetizing device

    E-Print Network [OSTI]

    Gopman, Daniel B; Kent, Andrew D

    2012-01-01T23:59:59.000Z

    We report on an instrument for applying ac and dc magnetic fields by capturing the flux from a rotating permanent magnet and projecting it between two adjustable pole pieces. This can be an alternative to standard electromagnets for experiments with small samples or in probe stations in which an applied magnetic field is needed locally, with advantages that include a compact form-factor, very low power requirements and dissipation as well as fast field sweep rates. This flux capture instrument (FLUXCAP) can produce fields from -400 to +400 mT, with field resolution less than 1 mT. It generates static magnetic fields as well as ramped fields, with ramping rates as high as 10 T/s. We demonstrate the use of this apparatus for studying the magnetotransport properties of spin-valve nanopillars, a nanoscale device that exhibits giant magnetoresistance.

  12. Future Directions in Engines and Fuels

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

    Future Directions in Engines and Fuels 7 Specification HECS I (current) 1.6l 4-Cyl. Diesel Engine 60 kWl spec. Power (limited PFP) Euro 6 wo DeNOx (<1700 kg) ...

  13. High-Current Accelerators

    E-Print Network [OSTI]

    Lawrence, Ernest O.

    1955-01-01T23:59:59.000Z

    F i g . 13 F i g . 14 A 48 ACCELERATOR F i g . 25 F i g . 16supply. Extrapolation of accelerator energy and current9 . A-48 high-current accelerator, low-velocity end. Fig.

  14. Diffusion current in a system of coupled Josephson junctions

    SciTech Connect (OSTI)

    Shukrinov, Yu. M., E-mail: shukrinv@theor.jinr.ru; Rahmonov, I. R. [Joint Institute for Nuclear Research (Russian Federation)

    2012-08-15T23:59:59.000Z

    The role of a diffusion current in the phase dynamics of a system of coupled Josephson junctions (JJs) has been analyzed. It is shown that, by studying the temporal dependences of the superconducting, quasi-particle, diffusion, and displacement currents and the dependences of average values of these currents on the total current, it is possible to explain the main features of the current-voltage characteristic (CVC) of the system. The effect of a diffusion current on the character of CVC branching in the vicinity of a critical current and in the region of hysteresis, as well as on the part of CVC branch corresponding to a parametric resonance in the system is demonstrated. A clear interpretation of the differences in the character of CVC branching in a model of capacitively coupled JJs (CCJJ model) and a model of capacitive coupling with diffusion current (CCJJ+DC model) is proposed. It is shown that a decrease in the diffusion current in a JJ leads to the switching of this junction to an oscillating state. The results of model calculations are qualitatively consistent with the experimental data.

  15. Control of carbon nanotube growth directions and morphology by direct current plasma enhanced chemical vapor deposition

    E-Print Network [OSTI]

    AuBuchon, Joseph Francis

    2006-01-01T23:59:59.000Z

    Pierard, A. Fonseca, Z. Konya, I. Willems, G. Van Tendeloo,D. Mehn, G. Galbaes, Z. Konya, I. Kiricsi, Catal. Today 76,

  16. Reduction of DC-link Capacitor in Case of Cascade Multilevel Converters by means of Reactive Power

    E-Print Network [OSTI]

    Teodorescu, Remus

    to integrate wind generator to multi- terminal dc collection network are few such examples. The basic block

  17. Current to Current | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublic Utilities Address: 160Benin:EnergyWisconsin:2003)Crowley County,Curran, Illinois: EnergyCurrentCurrent to

  18. Finite Element Modelling of the Sawing of DC Cast AA2024 Aluminium Alloy Slabs

    SciTech Connect (OSTI)

    Drezet, J.-M. [Computational Materials Laboratory, School of Engineering, Ecole Polytechnique Federale de Lausanne, Station 12, CH-1015 Lausanne (Switzerland); Ludwig, O. [Calcom-ESI SA, PSE-A, CH-1015 Lausanne (Switzerland); Heinrich, B. [Alcan Aluminium Valais SA, CH3960 Sierre (Switzerland)

    2007-04-07T23:59:59.000Z

    In the semi-continuous casting of large cross-section rolling sheet ingots of high-strength aluminum alloys (2xxx and 7xxx series), the control of the residual (internal) stresses generated by the non-uniform cooling becomes a necessity. These stresses must be relieved by a thermal treatment before the head and foot of the ingot can be cut. Otherwise, the saw can be caught owing to compressive stresses or cut parts may be ejected thus injuring people or damaging equipment. These high added-value ingots need to be produced in secure conditions. Moreover, a better control of the sawing procedure could allow the suppression of the thermal treatment and therefore save time and energy. By studying the stress build-up during casting and the stress relief during sawing, key parameters for the control and optimization of the processing steps, can be derived. To do so, the direct chill (DC) casting of the AA2024 alloy is modeled with ABAQUS 6.5 with special attention to the thermo-mechanical properties of the alloy. The sawing operation is then simulated by removing mesh elements so as to reproduce the progression of the saw in the ingot. Preliminary results showing the stress relief during sawing accompanied by the risk of saw blocking due to compression or initiating a crack ahead of the saw, are analyzed with an approach based on the rate of strain energy release.

  19. Solid-state NMR studies for DC 745: April--May 2000

    SciTech Connect (OSTI)

    Stephens, T.; Labouriau, A.

    2000-12-01T23:59:59.000Z

    Powles et al. reported in 1961 that pdydimethyl siloxane melts exhibit a transverse decay of nuclear spin magnetization (T{sub 2}) that is nonexponential. This observation was interpreted in terms of the proton NMR signal from the melt having characteristics of a broad line. Since then, similar findings were obtained for other polymer melts too. Accordingly to Powles et al. this peculiar proton line shape was the result of an intramolecular direct dipole-dipole interaction between a pair of protons. They also suggested that this dipolar interaction was weak because the dipolar interaction was motionally averaged since the orientation-dependent local dipolar field is modulated by molecular dynamics. In sum, the consequences and the origins of nuclear spin correlations in viscous polymer melts were recognized almost 4 decades ago. In the 1970s, Cohen-Addad suggested that these weak proton dipolar interactions could be used to characterize polymer melts and networks. In this work, we have used some of these ideas to probe the effects of thermal treatments on the proton spin-spin relaxation times for DC745.

  20. Influence of the transverse dimension on the structure and properties of dc glow discharges

    SciTech Connect (OSTI)

    Bogdanov, E. A. [St. Petersburg State University, St. Petersburg 198904 (Russian Federation); Adams, S. F. [Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433 (United States); Demidov, V. I. [Department of Physics, West Virginia University, Morgantown, West Virginia 26506 (United States); Kudryavtsev, A. A. [Department of Optics, St. Petersburg State University, St. Petersburg 198904 (Russian Federation); Williamson, J. M. [UES, Inc., 4401 Dayton-Xenia Rd., Beavercreek, Ohio 45432 (United States)

    2010-10-15T23:59:59.000Z

    Two-dimensional (2D) simulations of a dc glow discharge with a cold cathode in argon have been performed for various radii of the discharge tube. It is shown that the loss of the charged particles to the walls can significantly affect plasma parameters as well as properties of the cathode sheath. The longitude dimensions of the negative glow and Faraday dark space depend on the transverse loss of the charge particles and are not consistently predicted with a 1D model. The common assumption that the cathode sheath can be analyzed independently of the plasma also may not be valid. The transverse inhomogeneity of the plasma leads to a change in the current density distribution over the cathode surface. The thickness of the cathode sheath can vary with radial distance from the discharge axis, even for the case of negligible radial loss of the charge particles. The 2D model results provide an analysis of the conditions of applicability of the 1D model.

  1. Improving the dynamic performance of a complex AC/DC system by HVDC control modifications

    SciTech Connect (OSTI)

    Hammad, A.E. (ABB Power Systems, Baden (CH)); Gagnon, J. (Hydro Quebec, Montreal (CA)); McCallum, D. (IREQ, Montreal (CA))

    1990-10-01T23:59:59.000Z

    The power system of Hydro-Quebec has a peak load of approximately 27 GW. The great distance between the production sites and the load centers introduces stability limitations, which is the reason why the Quebec grid cannot be economically synchronized (through ac transmission with limited capacity) with the U.S. northeastern network. Power exports are therefore dependent on the use of HVDC links of which Hydro-Quebec now possesses five, for a capacity of over 2600 MW. Such a capacity will again soon increase. At the moment, the Chateauguay scheme has the largest HVDC capacity. It transfers 1000 MW by means of two Back-to-Back converter blocks. Various automatic control systems are installed on the Chateauguay scheme owing to the fact that a single circuit of a 765 kV ac line transmits the output of both the HVDC converter stations as well as the output from Beauharnois hydro generating station. Such controls have performed satisfactorily since 1984. However, a remarkable improvement of the overall ac/dc system dynamic performance can be gained by making certain modifications in some of these HVDC system controls. This paper presents the salient features of such control modifications, currently under consideration, using the results of an investigation by digital and analogue simulations that demonstrate the achieved improvements.

  2. Low noise charge sensitive preamplifier DC stabilized without a physical resistor

    DOE Patents [OSTI]

    Bertuccio, Giuseppe (Brianza, IT); Rehak, Pavel (Patchogue, NY); Xi, Deming (Beijing, CN)

    1994-09-13T23:59:59.000Z

    The invention is a novel charge sensitive preamplifier (CSP) which has no resistor in parallel with the feedback capacitor. No resetting circuit is required to discharge the feedback capacitor. The DC stabilization of the preamplifier is obtained by means of a second feedback loop between the preamplifier output and the common base transistor of the input cascode. The input transistor of the preamplifier is a Junction Field Transistor (JFET) with the gate-source junction forward biased. The detector leakage current flows into this junction. This invention is concerned with a new circuit configuration for a charge sensitive preamplifier and a novel use of the input Field Effect Transistor of the CSP itself. In particular this invention, in addition to eliminating the feedback resistor, eliminates the need for external devices between the detector and the preamplifier, and it eliminates the need for external circuitry to sense the output voltage and reset the CSP. Furthermore, the noise level of the novel CSP is very low, comparable with the performance achieved with other solutions. Experimental tests prove that this configuration for the charge sensitive preamplifier permits an excellent noise performance at temperatures including room temperature. An equivalent noise charge of less than 20 electrons r.m.s. has been measured at room temperature by using a commercial JFET as input device of the preamplifier.

  3. Low noise charge sensitive preamplifier DC stabilized without a physical resistor

    DOE Patents [OSTI]

    Bertuccio, G.; Rehak, P.; Xi, D.

    1994-09-13T23:59:59.000Z

    The invention is a novel charge sensitive preamplifier (CSP) which has no resistor in parallel with the feedback capacitor. No resetting circuit is required to discharge the feedback capacitor. The DC stabilization of the preamplifier is obtained by means of a second feedback loop between the preamplifier output and the common base transistor of the input cascode. The input transistor of the preamplifier is a Junction Field Transistor (JFET) with the gate-source junction forward biased. The detector leakage current flows into this junction. This invention is concerned with a new circuit configuration for a charge sensitive preamplifier and a novel use of the input Field Effect Transistor of the CSP itself. In particular this invention, in addition to eliminating the feedback resistor, eliminates the need for external devices between the detector and the preamplifier, and it eliminates the need for external circuitry to sense the output voltage and reset the CSP. Furthermore, the noise level of the novel CSP is very low, comparable with the performance achieved with other solutions. Experimental tests prove that this configuration for the charge sensitive preamplifier permits an excellent noise performance at temperatures including room temperature. An equivalent noise charge of less than 20 electrons r.m.s. has been measured at room temperature by using a commercial JFET as input device of the preamplifier. 6 figs.

  4. Low-energy dc ion source for low operating pressure

    SciTech Connect (OSTI)

    Oks, Efim, E-mail: oks@opee.hcei.tsc.ru [Institute of High Current Electronics, Russian Academy of Sciences, Akademichesky ave. 2/3, Tomsk 634055 (Russian Federation); State University of Control Systems and Radioelectronics, 40 Lenin Ave., Tomsk 634050 (Russian Federation); Shandrikov, Maxim [Institute of High Current Electronics, Russian Academy of Sciences, Akademichesky ave. 2/3, Tomsk 634055 (Russian Federation); Salvadori, Cecilia [Institute of Physics, University of São Paulo, C.P. 66318, CEP 05315-970 São Paulo S.P. (Brazil); Brown, Ian [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720 (United States)

    2014-08-15T23:59:59.000Z

    We report on an experimental study of an ion source based on a Penning discharge with a cold hollow cathode in crossed electric and magnetic fields. The minimum vacuum chamber operating pressure was 3 × 10{sup ?5} Torr for argon and 5 × 10{sup ?5} Torr for hydrogen. The use of a hollow cathode allowed decreasing the discharge operating voltage down to 350 V at a discharge current of ?100 mA. At a discharge current of 100 mA and beam accelerating voltage of 2 kV, the ion current was 2.5 mA for argon and 8 mA for hydrogen, and the ion beam on-axis current density 170 and 450 ?A/cm{sup 2}, respectively. The current-voltage characteristics of the discharge and the radial ion beam current density distribution were measured. The influence of pressure on the discharge parameters and their time stability was investigated.

  5. Observation and cancellation of the dc Stark shift in strontium optical lattice clocks

    E-Print Network [OSTI]

    Lodewyck, Jérôme; Lorini, Luca; Gurov, Mikhail; Lemonde, Pierre

    2011-01-01T23:59:59.000Z

    We report on the observation of a dc Stark frequency shift at the $10^{-13}$ level by comparing two strontium optical lattice clocks. This frequency shift arises from the presence of electric charges trapped on dielectric surfaces placed under vacuum close to the atomic sample. We show that these charges can be eliminated by shining UV light on the dielectric surfaces, and characterize the residual dc Stark frequency shift on the clock transition at the $10^{-18}$ level by applying an external electric field. This study shows that the dc Stark shift can play an important role in the accuracy budget of lattice clocks, and should be duly taken into account.

  6. A High Frequency Isolated Current-fed Bidirectional DC/AC Converter For Grid-Tied Energy Storage System

    E-Print Network [OSTI]

    King Jet, TSENG

    2013-01-01T23:59:59.000Z

    for Grid-tied Energy Storage System XhaFreh qu, K.J. uneng,grid-tied energy storage systems (ESS) will be voltage to aGrid-tied energy storage system (ESS) is increasingly used

  7. Current Testbed Research

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

    Current Testbed Research Previous Testbed Research Proposal Process Terms and Conditions Dark Fiber Testbed Performance (perfSONAR) Software & Tools Development Partnerships...

  8. 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.

  9. Another face of DIRECT

    E-Print Network [OSTI]

    chiter

    2007-08-01T23:59:59.000Z

    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 ...

  10. DC transformer for DC/DC connection in HVDC network M. Jimenez Carrizosa1, A. Benchaib2, P. Alou3, G. Damm4

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    source converters), in HVDC systems were used the CSC (current source converters) to carry out the inversion and rectification. VSC converters use IGBTs and CSC use thyristors. VSC-HVDC systems present many advantages compared with CSC-HVDC systems. Some of them are: simultaneous control of active and reactive

  11. Data:C4030a55-9263-4760-854e-f64dc5b1450a | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onb5-dcc1fcffd1f2bb71-d4159a938742 No revision has4dc5b1450a No revision has been approved for this page. It is currently

  12. Current to Current Corporation | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublic Utilities Address: 160Benin:EnergyWisconsin:2003)Crowley County,Curran, Illinois: EnergyCurrent

  13. Ultracapacitor current collector

    DOE Patents [OSTI]

    Jerabek, Elihu Calfin (Glenmont, NY); Mikkor, Mati (Ann Arbor, MI)

    2001-10-16T23:59:59.000Z

    An ultracapacitor having two solid, nonporous current collectors, two porous electrodes separating the collectors, a porous separator between the electrodes and an electrolyte occupying the pores in the electrodes and separator. At least one of the current collectors comprises a conductive metal substrate coated with a metal nitride, carbide or boride coating.

  14. Solid-state circuit breaker with current-limiting characteristic using a superconducting coil

    DOE Patents [OSTI]

    Boenig, H.J.

    1982-08-16T23:59:59.000Z

    A thyristor bridge interposes an ac source and a load. A series connected DC source and superconducting coil within the bridge biases the thyristors thereof so as to permit bidirectional ac current flow therethrough under normal operating conditions. Upon a fault condition a control circuit triggers the thyristors so as to reduce ac current flow therethrough to zero in less than two eyeles and to open the bridge thereafter. Upon a temporary overload condition the control circuit triggers the thyristors so as to limit ac current flow therethrough to an acceptable level.

  15. Microstructure and DC electrical conductivity of spinel nickel ferrite sintered in air and nitrogen atmospheres

    SciTech Connect (OSTI)

    Liu, Baogang; Zhou, Kechao [State Key Laboratory of Powder Metallurgy, Powder Metallurgy Research Institute, Central South University, No. 932 South Lushan Road, Changsha 410083 (China)] [State Key Laboratory of Powder Metallurgy, Powder Metallurgy Research Institute, Central South University, No. 932 South Lushan Road, Changsha 410083 (China); Li, Zhiyou, E-mail: 13786124789@126.com [State Key Laboratory of Powder Metallurgy, Powder Metallurgy Research Institute, Central South University, No. 932 South Lushan Road, Changsha 410083 (China)] [State Key Laboratory of Powder Metallurgy, Powder Metallurgy Research Institute, Central South University, No. 932 South Lushan Road, Changsha 410083 (China); Zhang, Dou; Zhang, Lei [State Key Laboratory of Powder Metallurgy, Powder Metallurgy Research Institute, Central South University, No. 932 South Lushan Road, Changsha 410083 (China)] [State Key Laboratory of Powder Metallurgy, Powder Metallurgy Research Institute, Central South University, No. 932 South Lushan Road, Changsha 410083 (China)

    2010-11-15T23:59:59.000Z

    In recent years, the development of inert anode materials has gained considerable attention because such materials are capable of producing only environment-friendly O{sub 2} and saving energy during aluminum electrolysis. Nickel ferrite was prepared by a solid-state reaction as the inert anode in this study and its microstructures and direct current conductivities were analyzed in detail regarding the effects of different sintering atmospheres. A single-phase spinel structure was confirmed for all samples by X-ray powder diffraction. The grain sizes and the relative densities of the samples sintered in nitrogen increased by over 7 {mu}m and 10.8%, respectively, compared to those sintered in air. The direct current conductivities of the samples sintered in nitrogen showed a drastic increase compared to those sintered in air, believed to be due to the effects of increased Fe{sup 2+} ion concentration at octahedral sites and the increase of the relative density.

  16. Eddy current technique for predicting burst pressure

    DOE Patents [OSTI]

    Petri, Mark C. (Yorkville, IL); Kupperman, David S. (Oak Park, IL); Morman, James A. (Woodridge, IL); Reifman, Jaques (Western Springs, IL); Wei, Thomas Y. C. (Downers Grove, IL)

    2003-01-01T23:59:59.000Z

    A signal processing technique which correlates eddy current inspection data from a tube having a critical tubing defect with a range of predicted burst pressures for the tube is provided. The method can directly correlate the raw eddy current inspection data representing the critical tubing defect with the range of burst pressures using a regression technique, preferably an artificial neural network. Alternatively, the technique deconvolves the raw eddy current inspection data into a set of undistorted signals, each of which represents a separate defect of the tube. The undistorted defect signal which represents the critical tubing defect is related to a range of burst pressures utilizing a regression technique.

  17. Voltage controlled current source

    DOE Patents [OSTI]

    Casne, Gregory M. (Pittsburgh, PA)

    1992-01-01T23:59:59.000Z

    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.

  18. Vehicle Technologies Office Merit Review 2014: High Performance DC Bus Film Capacitor

    Broader source: Energy.gov [DOE]

    Presentation given by GE Global Research at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about high performance DC bus...

  19. Strontium Titanate DC Electric Field Switchable and Tunable Bulk Acoustic Wave Solidly Mounted Resonator

    E-Print Network [OSTI]

    York, Robert A.

    Strontium Titanate DC Electric Field Switchable and Tunable Bulk Acoustic Wave Solidly Mounted Abstract - A voltage switchable/tunable strontium titanate solidly mounted BAW resonator was implemented films, piezoelectric resonators. I. INTRODUCTION Strontium titanate (STO) and barium strontium titanate

  20. Application to Export Electric Energy OE Docket No. EA-351 DC...

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

    DC Energy Dakota, LLC Application to export electric energy OE Docket No. EA-210-B PPL EnergyPlus, LLC Application to Export Electric Energy OE Docket No. EA-354 Endure...

  1. Hydrogen Storage Systems Analysis Working Group Meeting Argonne National Laboratory DC Offices

    E-Print Network [OSTI]

    Hydrogen Storage Systems Analysis Working Group Meeting Argonne National Laboratory DC Offices 955 by Romesh Kumar Argonne National Laboratory and Laura Verduzco Sentech, Inc. February 28, 2007 #12;SUMMARY

  2. Dean's Report from DC (Nov 2011) 1: Federal Science Funding PerspecAve

    E-Print Network [OSTI]

    Wang, Yuqing

    Dean's Report from DC (Nov 2011) 1: Federal Science Funding Perspec (AdministraAon's) FY12 PrioriAes Ã? Moving toward a clean energy future to reduce dependence on energy imports while curbing greenhouse gas emissions Ã? Understanding

  3. Washington, D.C. : essays on the city form of a capital

    E-Print Network [OSTI]

    Kousoulas, George

    1985-01-01T23:59:59.000Z

    This thesis is an exploration of the city form of Washington. D.C. through four independent essays. Each essay examines a different aspect of the city: its monumentality as determined by its relationship with the nation ...

  4. Area Efficient D/A Converters For Accurate DC Operation Brandon Royce Greenley

    E-Print Network [OSTI]

    Moon, Un-Ku

    . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 6.2 Mismatch Modeling For Area Optimization . . . . . . . . . . . . . . . . . . . . . . . 51 6Area Efficient D/A Converters For Accurate DC Operation by Brandon Royce Greenley A THESIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 5.1 Measurement Setup

  5. DC-OPF Formulation with Price-Sensitive Demand Bids Junjie Sun and Leigh Tesfatsion

    E-Print Network [OSTI]

    Tesfatsion, Leigh

    DC-OPF Formulation with Price-Sensitive Demand Bids Junjie Sun and Leigh Tesfatsion Last Revised (TNCS) subject to various transmission constraints. As explained at length in Sun and Tesfation (2007

  6. High luminosity, slow ejecta and persistent carbon lines: SN 2009dc challenges thermonuclear explosion scenarios .

    E-Print Network [OSTI]

    Taubenberger, S.

    2011-01-01T23:59:59.000Z

    ??Extended optical and near-IR observations reveal that SN 2009dc shares a number of similarities with normal Type Ia supernovae (SNe Ia), but is clearly overluminous,… (more)

  7. Nonlinear modal interaction in HVDC/AC power systems with dc power modulation

    SciTech Connect (OSTI)

    Ni, Y.X. [Tsinghua Univ., Beijing (China)] [Tsinghua Univ., Beijing (China); Vittal, V.; Kliemann, W.; Fouad, A.A. [Iowa State Univ., Ames, IA (United States)] [Iowa State Univ., Ames, IA (United States)

    1996-11-01T23:59:59.000Z

    In this paper investigation of nonlinear modal interaction using the normal form of vector fields technique is extended to HVDC/AC power systems with dc power modulation. The ac-dc interface equations are solved to form a state space model with second order approximation. Using the normal form technique, the system`s nonlinear dynamic characteristics are obtained. The proposed approach is applied to a 4-generator HVDC/AC test power system, and compare with the time domain solution.

  8. Ratcheting of driven attracting colloidal particles: Temporal density oscillations and current multiplicity

    E-Print Network [OSTI]

    Andrey Pototsky; Andrew J. Archer; Sergey E. Savel'ev; Uwe Thiele; Fabio Marchesoni

    2011-03-15T23:59:59.000Z

    We consider the unidirectional particle transport in a suspension of colloidal particles which interact with each other via a pair potential having a hard-core repulsion plus an attractive tail. The colloids are confined within a long narrow channel and are driven along by a DC or an AC external potential. In addition, the walls of the channel interact with the particles via a ratchet-like periodic potential. We use dynamical density functional theory to compute the average particle current. In the case of DC drive, we show that as the attraction strength between the colloids is increased beyond a critical value, the stationary density distribution of the particles loses its stability leading to depinning and a time dependent density profile. Attraction induced symmetry breaking gives rise to the coexistence of stable stationary density profiles with different spatial periods and time-periodic density profiles, each characterized by different values for the particle current.

  9. Electric field induced spin-polarized current

    DOE Patents [OSTI]

    Murakami, Shuichi; Nagaosa, Naoto; Zhang, Shoucheng

    2006-05-02T23:59:59.000Z

    A device and a method for generating an electric-field-induced spin current are disclosed. A highly spin-polarized electric current is generated using a semiconductor structure and an applied electric field across the semiconductor structure. The semiconductor structure can be a hole-doped semiconductor having finite or zero bandgap or an undoped semiconductor of zero bandgap. In one embodiment, a device for injecting spin-polarized current into a current output terminal includes a semiconductor structure including first and second electrodes, along a first axis, receiving an applied electric field and a third electrode, along a direction perpendicular to the first axis, providing the spin-polarized current. The semiconductor structure includes a semiconductor material whose spin orbit coupling energy is greater than room temperature (300 Kelvin) times the Boltzmann constant. In one embodiment, the semiconductor structure is a hole-doped semiconductor structure, such as a p-type GaAs semiconductor layer.

  10. A Segmented Drive System with a Small DC Bus Capacitor

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

    weight for inverters. Currently, it contributes - Cost and weight, up to 23% of an inverter - Volume, up to 30% of an inverter * Ability of film capacitors to operate at higher...

  11. Current control circuitry

    DOE Patents [OSTI]

    Taubman, Matthew S. (Richland, WA)

    2005-03-15T23:59:59.000Z

    Among the embodiments of the present invention is an apparatus that includes a transistor (30), a servo device (40), and a current source (50). The servo device (40) is operable to provide a common base mode of operation of the transistor (30) by maintaining an approximately constant voltage level at the transistor base (32b). The current source (150) is operable to provide a bias current to the transistor (30). A first device (24) provides an input signal to an electrical node (70) positioned between the emitter (32e) of the transistor (30) and the current source (50). A second device (26) receives an output signal from the collector (32c) of the transistor (30).

  12. Directives Quarterly Updates - DOE Directives, Delegations, and

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-Series to UserProduct: https://www.directives.doe.gov/directives/directives

  13. Recent advances with quiescent power supply current (I sub DDQ ) testing at Sandia using the HP82000

    SciTech Connect (OSTI)

    Righter, A.W.; Leong, D.J.; Cox, L.B.

    1991-01-01T23:59:59.000Z

    Last year at the HP82000 Users Group Meeting, Sandia National Laboratories gave a presentation on I{sub DDQ} testing. This year, we will present some advances on this testing including DUT board fixturing, external DC PMU measurement, and automatic IDD-All circuit calibration. This paper is geared more toward implementation than theory, with results presented from Sandia tests. After a brief summary I{sub DDQ} theory and testing concepts, we will describe how the break (hold state) vector and data formatting present a test vector generation concern for the HP82000. We than discuss fixturing of the DUT board for both types of I{sub DDQ} measurement, and how the continuity test and test vector generation must be taken into account. Results of a test including continuity, IDD-All and I{sub DDQ} Value measurements will be shown. Next, measurement of low current using an external PMU is discussed, including noise considerations, implementation and some test results showing nA-range measurements. We then present a method for automatic calibration of the IDD-All analog comparator circuit using RM BASIC on the HP82000, with implementation and measurement results. Finally, future directions for research in this area will be explored. 14 refs., 16 figs.

  14. Electrochemical Performance and Stability of the Cathode for Solid Oxide Fuel Cells. I. Cross Validation of Polarization Measurements by Impedance Spectroscopy and Current-Potential Sweep

    SciTech Connect (OSTI)

    Zhou, Xiao Dong; Pederson, Larry R.; Templeton, Jared W.; Stevenson, Jeffry W.

    2009-12-09T23:59:59.000Z

    The aim of this paper is to address three issues in solid oxide fuel cells: (1) cross-validation of the polarization of a single cell measured using both dc and ac approaches, (2) the precise determination of the total areal specific resistance (ASR), and (3) understanding cathode polarization with LSCF cathodes. The ASR of a solid oxide fuel cell is a dynamic property, meaning that it changes with current density. The ASR measured using ac impedance spectroscopy (low frequency interception with real Z´ axis of ac impedance spectrum) matches with that measured from a dc IV sweep (the tangent of dc i-V curve). Due to the dynamic nature of ASR, we found that an ac impedance spectrum measured under open circuit voltage or on a half cell may not represent cathode performance under real operating conditions, particularly at high current density. In this work, the electrode polarization was governed by the cathode activation polarization; the anode contribution was negligible.

  15. A study of the Antilles Current using moored current meter arrays

    E-Print Network [OSTI]

    Maloney, William Everett

    1967-01-01T23:59:59.000Z

    characteristics of the Savcnius rotor have been reported previously by Gaul (1962). The output from the current meter is a ro11 of 16 mm photographic film containing current direction and speed data, data on case inclination, and timing pulses. An example... the summer npeia ions, wind directions and speeds were typical for this subtropical latitude being gener;illy out of the east at Table 2. Mooring nositioning data. oorlpg; I I IFix No. !:Date, " Time I !I, " L'ST :I ~L*'- 0. ! I ILongitude Il...

  16. Direct/Indirect Costs

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

    1997-03-28T23:59:59.000Z

    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.

  17. Direct Loan Program (Connecticut)

    Broader source: Energy.gov [DOE]

    The Connecticut Development Authority’s Direct Loan Program provides direct senior and subordinated loans and mezzanine investments to companies creating or maintaining jobs. Up to $20,000 per job...

  18. Directives System Manual

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

    1998-01-30T23:59:59.000Z

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

  19. Direct process for explosives

    DOE Patents [OSTI]

    Akst, I.B.; Stinecipher, M.M.

    1982-10-12T23:59:59.000Z

    A direct process of making ethylenediamine dinitrate through the reaction of ethylenediamine and ammonium nitrate is described.

  20. Transformer current sensor for superconducting magnetic coils

    DOE Patents [OSTI]

    Shen, Stewart S. (Oak Ridge, TN); Wilson, C. Thomas (Norris, TN)

    1988-01-01T23:59:59.000Z

    A transformer current sensor having primary turns carrying a primary current for a superconducting coil and secondary turns only partially arranged within the primary turns. The secondary turns include an active winding disposed within the primary turns and a dummy winding which is not disposed in the primary turns and so does not experience a magnetic field due to a flow of current in the primary turns. The active and dummy windings are wound in opposite directions or connected in series-bucking relationship, and are exposed to the same ambient magnetic field. Voltages which might otherwise develop in the active and dummy windings due to ambient magnetic fields thus cancel out. The resultant voltage is purely indicative of the rate of change of current flowing in the primary turns.

  1. Response of DC and PAS to size fractionated particles

    E-Print Network [OSTI]

    Minnesota, University of

    · Medium-duty, direct injection, turbocharged Diesel engine ­ all tests at 1400 rpm ­ 10% load, large nuclei mode, VOF 60% ­ 50% load, no nuclei mode, VOF 30% ­ 75% load, no nuclei mode, VOF 15 of monodisperse aerosols with a DMA ·All the measurement should be above the detection limit curve to yield

  2. FEA Analysis of AP-0 Target Hall Collection Lens (Current Design)

    SciTech Connect (OSTI)

    Hurh, P.G.; Tang, Z.

    2001-06-22T23:59:59.000Z

    The AP-0 Target Hall Collection Lens is a pulsed device which focuses anti-protons just downstream of the Target. Since the angles at which the anti-protons depart the Target can be quite large, a very high focusing strength is required to maximize anti-proton capture into the downstream Debuncher Ring. The current design of the Collection Lens was designed to operate with a focusing gradient of 1,000 T/m. However, multiple failures of early devices resulted in lowering the normal operating gradient to about 750 T/m. At this gradient, the Lens design fares much better, lasting several million pulses, but ultimately still fails. A Finite Element Analysis (FEA) has been performed on this Collection Lens design to help determine the cause and/or nature of the failures. The Collection Lens magnetic field is created by passing high current through a central conductor cylinder. A uniform current distribution through the cylinder will create a tangential or azimuthal magnetic field that varies linearly from zero at the center of the cylinder to a maximum at the outer surface of the cylinder. Anti-proton particles passing through this cylinder (along the longitudinal direction) will see an inward focusing kick back toward the center of the cylinder proportional to the magnetic field strength. For the current Lens design a gradient of 1,000 T/m requires a current of about 580,000 amps. Since the DC power and cooling requirements would be prohibitive, the Lens is operated in a pulsed mode. Each pulse is half sine wave in shape with a pulse duration of about 350 microseconds. Because of the skin effect, the most uniform current density actually occurs about two-thirds of the way through the pulse. This means that the maximum current of the pulse is actually higher than that required in the DC case (about 670,000 amps). Since the beam must pass through the central conductor cylinder it must be made of a conducting material that is also very 'transparent' to the beam. For the Collection Lens, this material is lithium (Li). The central conductor cylinder is a lithium cylinder 1 cm in radius and about 14 cm long. Figure 1 shows this cylinder in a cross-section view of the Collection Lens. Surrounding the central cylinder is a jacket of titanium alloy (6Al-4V ELI) called the septum. The septum's purpose is to contain the lithium against various thermal and magnetic forces while allowing cooling (melting point of Li is 180.5 C) by an annular water passage. The ends of the Li cylinder are bound by end windows made of beryllium (Be) and a thin titanium (ti) foil. The foil protects the Be from the corrosive effects of Li and the Be window provides the structural support. The two end windows sit in pockets in the ends of two larger steel cylinders or body halves. The body halves are separated from each other by ceramic spacers. The body halves, septum and end windows are connected to each other by nickel (Ni) seals which preserve the boundary of the lithium conductor. Force required to make these seals is provided by eight Ti 6Al-4V ELI tie rods which traverse the entire assembly. These tie rods also resist magnetic forces that attempt to separate the body halves during the current pulse. There are several insulating components that are used to isolate one side of the lens from the other and force the current through the central Li conductor. The volumes of Li at each end of the central conductor cylinder outside the septum but inside the body halves are called buffer volumes. These buffer volumes serve two roles. One, they provide a low resistance current path to the end of the central conductor cylinder. Two, they provide a volume for Li to expand into during the current pulse. For the latter it is assumed that magnetic forces and thermal strains will force lithium from the central cylinder and into the buffer volumes during the current pulse. There are several loads on the Lens that are developed during a current pulse. High magnetic loads act radially and longitudinally outward on the steel body halves and radially inward on the central

  3. UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON D.C. 20460

    E-Print Network [OSTI]

    to update the environmental protection standards for uranium mining because current regulations, promulgated monitoring networks at ISL uranium mines, including wells within the production area to compare post- and pre preliminary framework of considerations applicable to groundwater monitoring at ISL uranium mines

  4. Current address: Samuel Johnson

    E-Print Network [OSTI]

    Johnson, Samuel

    CV: E-mail : Homepage: Current address: Samuel Johnson samuel.johnson@imperial.ac.uk www. #12;Submitted work 1. The meaning of niche: Cause or consequence of food-web structure?, S. Johnson, V learning, S. Johnson, J. Marro, and J.J. Torres, PLoS ONE 8(1): e50276 (2013) 3. Enhancing neural network

  5. Hydrogen Delivery- Current Technology

    Broader source: Energy.gov [DOE]

    Hydrogen is transported from the point of production to the point of use via pipeline, over the road in cryogenic liquid trucks or gaseous tube trailers, or by rail or barge. Read on to learn more about current hydrogen delivery and storage technologies.

  6. Directives Templates - DOE Directives, Delegations, and Requirements

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-Series to UserProduct:Directives Templates by Website Administrator Directives

  7. Joule heating generated by spin current through Josephson junctions

    SciTech Connect (OSTI)

    Takahashi, S.; Yamashita, T.; Koyama, T.; Maekawa, S.; Imamura, H.

    2001-06-01T23:59:59.000Z

    We theoretically study the spin-polarized current flowing through a Josephson junction (JJ) in a spin injection device. When the spin-polarized current is injected from a ferromagnet in a superconductor (SC), the charge current is carried by the superconducting condensate (Cooper pairs), while the spin-up and spin-down currents flow in equal magnitude but in the opposite direction in a SC, because of no quasiparticle charge current in the SC. This indicates that not only the Josephson current but also the spin current flow across JJ at zero bias voltage, thereby generating Joule heating by the spin current. The result provides a new method for detecting the spin current by measuring Joule heating at JJ. {copyright} 2001 American Institute of Physics.

  8. Current Status of Concentrator Photovoltaic (CPV) Technology

    SciTech Connect (OSTI)

    Philipps, S. P.; Bett, A. W.; Horowitz, K.; Kurtz, S.

    2015-01-01T23:59:59.000Z

    This report describes the current status of the market and technology for concentrator photovoltaic (CPV) cells and modules. Significant progress in CPV has been achieved, including record efficiencies for modules (36.7%) and cells (46%), as well as growth of large field installations in recent years. CPV technology may also have the potential to be cost-competitive on a levelized cost of energy (LCOE) basis in regions of high direct normal irradiance (DNI). The study includes an overview of all installations larger than 1 MW, information on companies currently active in the CPV field, efficiency data, and estimates of the LCOE in different scenarios.

  9. Soft-Switching High-Frequency AC-Link Universal Power Converters with Galvanic Isolation

    E-Print Network [OSTI]

    Amirabadi, Mahshid

    2013-08-07T23:59:59.000Z

    ) direct drive using wound-field synchronous generator [10]. ...................................................................................................... 6 Figure 6 Dc-dc buck-boost converter: (a) configuration, (b) energizing mode (mode 1), (c...) de-energizing mode (mode 2), (d) voltage and current waveforms ........ 12 Figure 7 An alternative representation of the dc-dc buck-boost converter ...................... 13 Figure 8 Dc-dc ac-link buck-boost converter: configuration, behavior...

  10. Abstract The series-input parallel-output dc-dc converter combination provides inherent sharing among the converters.

    E-Print Network [OSTI]

    Kimball, Jonathan W.

    for advanced digital loads. With this control in place, a "super-matched" current sharing control emerges gain produces a "super-match" characteristic that holds even during transient conditions, limited only to function independently, four input capacitors decouple the inputs. (It is advantageous to interleave

  11. Oscillation modes of dc microdischarges with parallel-plate geometry

    E-Print Network [OSTI]

    Stefanovi?, Ilija; Škoro, Nikola; Mari?, Dragana; Petrovi?, Zoran Lj; Winter, Jörg

    2011-01-01T23:59:59.000Z

    Two different oscillation modes in microdischarge with parallel-plate geometry has been observed: relaxation oscillations with frequency range between 1.23 and 2.1 kHz and free-running oscillations with 7 kHz frequency. The oscillation modes are induced by increasing power supply voltage or discharge current. For a given power supply voltage, there is a spontaneous transition from one to other oscillation mode and vice versa. Before the transition from relaxation to free-running oscillations, the spontaneous increase of oscillation frequency of relaxation oscillations form 1.3 kHz to 2.1 kHz is measured. Fourier Transform Spectra of relaxation oscillations reveal chaotic behaviour of microdischarge. Volt-Ampere characteristics associated with relaxation oscillations describes periodical transition between low current, diffuse discharge and normal glow. However, free-running oscillations appear in subnormal glow only.

  12. Solid Silicone Elastomer Material(DC745U)-Historical Overview and New Experimental Results

    SciTech Connect (OSTI)

    Ortiz-Acosta, Denisse [Los Alamos National Laboratory

    2012-08-08T23:59:59.000Z

    DC745U is a silicone elastomer used in several weapon systems. DC745U is manufactured by Dow Corning and its formulation is proprietary. Risk changes without notification to the customer. {sup 1}H and {sup 29}Si{l_brace}{sup 1}H{r_brace} NMR have previously determined that DC745U contains {approx} 98.5% dimethyl siloxane, {approx}1.5% methyl-phenyl siloxane, and a small amount (<1%) of vinyl siloxane repeat units that are converted to crosslinking sites. The polymer is filled with {approx} 38 wt.% of a mixture of fumed silica and quartz. Some conclusions are: (1) DMA shows that crystallization does have an effect on the mechanical properties of DC745U; (2) DMA shows that the crystallization is time and temperature dependent; (3) Mechanical tests show that DC745U undergo a crystalline transition at temperatures below -50 C; (4) Rate and temperature does not have an effect above crystalline transition; (5) Crystalline transition occurs faster at colder temperatures; (6) The material remains responsive and recovers after warming it to temperature above -40 C; (7) We were able to review all previous historical data on DC745U; (8) Identified specific gaps in materials understanding; (9) Developed design of experiments and testing methods to address gaps associated with post-curing and low temperature mechanical behavior; (10) Resolved questions of post-cure and alleviated concerns associated with low temperature mechanical behavior with soak time and temperature; and (11) This work is relevant to mission-critical programs and for supporting programmatic work for weapon research.

  13. Current Annualized Request

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion |Energy UsageAUDITVehiclesTankless orAChiefAppropriation FY 2012 FY 2013 FY 2014 Current

  14. Directives System Manual

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

    1995-10-16T23:59:59.000Z

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

  15. Departmental Directives Program

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

    2014-10-16T23:59:59.000Z

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

  16. Direct Loan Program (Kentucky)

    Broader source: Energy.gov [DOE]

    The Direct Loan Program, is designed to allow businesses to obtain the long term financing needed to encourage growth. The Kentucky Economic Development Finance Authority (KEDFA) may participate...

  17. Quantum pumping of valley current in strain engineered graphene

    SciTech Connect (OSTI)

    Wang, Jing [Department of Physics, University of Science and Technology of China, Hefei (China) [Department of Physics, University of Science and Technology of China, Hefei (China); Department of Physics and Materials Science and Centre for Functional Photonics, City University of Hong Kong, Hong Kong and City University of Hong Kong Shenzhen Research Institute, Shenzhen (China); Chan, K. S., E-mail: apkschan@cityu.edu.hk, E-mail: zjlin@ustc.edu.cn [Department of Physics and Materials Science and Centre for Functional Photonics, City University of Hong Kong, Hong Kong and City University of Hong Kong Shenzhen Research Institute, Shenzhen (China); Lin, Zijing, E-mail: apkschan@cityu.edu.hk, E-mail: zjlin@ustc.edu.cn [Department of Physics, University of Science and Technology of China, Hefei (China)] [Department of Physics, University of Science and Technology of China, Hefei (China)

    2014-01-06T23:59:59.000Z

    We studied the generation of valley dependent current by adiabatic quantum pumping in monolayer graphene in the presence of electric potential barriers, ferromagnetic field and strain. The pumped currents in the two valleys have same magnitudes and opposite directions; thus, a pure valley current is generated. The oscillation of the pumped pure valley current is determined by the Fabry-Perot resonances formed in the structure. In our calculation, the pumped pure valley current can be as high as 50?nA, which is measurable using present technologies. The proposed device is useful for the development of graphene valleytronic devices.

  18. Apparatus for electrode current control in linear MHD generators

    DOE Patents [OSTI]

    Demirjian, Ara M. (Arlington, MA); Solbes, Albert (Rancho Palos Verdes, CA)

    1984-01-01T23:59:59.000Z

    Apparatus for controlling a plurality of opposing, electrode, direct-currents at pre-set locations across a channel that comprises a converter for converting each electrode current into first and second periodic control signals which are 180.degree. out of phase with respect to each other and which have equal magnitudes corresponding to the magnitude of the associated electrode current; and couplers for magnetically coupling individual ones of the first control signals and for magnetically coupling individual ones of the second signals such that the corresponding electrode currents are equalized or rendered proportional by balancing the same in the same or constant ratios in accordance with the locations of the electrode currents.

  19. The DC field components of horizontal and vertical electric dipole sources immersed in three-layered stratified media

    E-Print Network [OSTI]

    Boyer, Edmond

    for the solution in the case of horizontal electric dipole (HED) radiation source and the single-component HertzThe DC field components of horizontal and vertical electric dipole sources immersed in three- ponents of the static (DC) fields of horizontal electric dipoles ( HEDs) and vertical electric dipoles

  20. Superconductivity for Electric Systems Annual Peer Review Washington, DC July 27-29, 2004. OAK RIDGE NATIONAL LABORATORY

    E-Print Network [OSTI]

    Superconductivity for Electric Systems Annual Peer Review Washington, DC ­ July 27-29, 2004. OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY American Superconductor Corporation U. Schoop, M. W&D support #12;Superconductivity for Electric Systems Annual Peer Review Washington, DC ­ July 27-29, 2004