National Library of Energy BETA

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)

    2010-01-01

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

    E-Print Network [OSTI]

    Essakiappan, Somasundaram

    2011-08-08

    demand for power converters with bi-directional capabilities. The objective of this thesis is to develop a high power quality, bi-directional AC-DC power converter that is a solution to the aforementioned problems. This thesis studies an existing topology...

  3. 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

    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 machinery. Direct current (DC) and Alternating Current (AC) transmission lines overhead are often suspected

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

    SciTech Connect (OSTI)

    Abas Goodarzi

    2011-01-31

    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. Fuzzy Estimation of DC Motor Winding Currents Innovatia Software

    E-Print Network [OSTI]

    Simon, Dan

    Fuzzy Estimation of DC Motor Winding Currents Dan Simon Innovatia Software 775 Rothrock Circle °ux is rotated in the desired direction of ofuzzy ¯ltering to motor winding current estimation stator windings. an attractive alternative to current estimation using In order to implement an e

  6. Low Cost, High Temperature, High Ripple Current DC Bus Capacitors...

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

    Low Cost, High Temperature, High Ripple Current DC Bus Capacitors Low Cost, High Temperature, High Ripple Current DC Bus Capacitors 2010 DOE Vehicle Technologies and Hydrogen...

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

    E-Print Network [OSTI]

    Khopkar, Rahul Vijaykumar

    2004-11-15

    the hard switchings by natural turn-off, thereby eliminating the heatsinks as well as the large dc link capacitor. A controlled rectifier together with a large inductor act as the current source. The only disadvantage is the large value of the dc link...

  8. Direct current uninterruptible power supply method and system

    DOE Patents [OSTI]

    Sinha, Gautam

    2003-12-02

    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.

  9. Development of a Novel Bi-Directional Isolated Multiple-Input DC-DC Converter

    SciTech Connect (OSTI)

    Li, H.

    2005-10-24

    There is vital need for a compact, lightweight, and efficient energy-storage system that is both affordable and has an acceptable cycle life for the large-scale production of electric vehicles (EVs) and hybrid electric vehicles (HEVs). Most of the current research employs a battery-storage unit (BU) combined with a fuel cell (FC) stack in order to achieve the operating voltage-current point of maximum efficiency for the FC system. A system block diagram is shown in Fig.1.1. In such a conventional arrangement, the battery is sized to deliver the difference between the energy required by the traction drive and the energy supplied by the FC system. Energy requirements can increase depending on the drive cycle over which the vehicle is expected to operate. Peak-power transients result in an increase of losses and elevated temperatures which result in a decrease in the lifetime of the battery. This research will propose a novel two-input direct current (dc) dc to dc converter to interface an additional energy-storage element, an ultracapacitor (UC), which is shown in Fig.1.2. It will assist the battery during transients to reduce the peak-power requirements of the battery.

  10. Soft-commutated direct current motor

    DOE Patents [OSTI]

    Hsu, J.S.

    1999-07-27

    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.

  11. Soft-commutated direct current motor

    DOE Patents [OSTI]

    Hsu, John S. (Oak Ridge, TN)

    1999-01-01

    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', B and B' 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.

  12. 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

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

    SciTech Connect (OSTI)

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

    2011-10-13

    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.

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

    E-Print Network [OSTI]

    Phase-Shifted Full Bridge DC-DC Converter with Energy Recovery Clamp and Reduced Circulating@aei.com Abstract - This paper introduces a full bridge converter with reduced circulating current and a reduction bridge converter operating at 32 kHz switching frequency. Losses and efficiency of the experimental

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

    SciTech Connect (OSTI)

    P.F. Schmit and N.J. Fisch

    2010-02-01

    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.

  16. 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

    2007-09-17

    PFC stage and trailing edge modulation for the second DC/DC converter stage can significantly reduce the ripple current and ripple voltage of the DC-link capacitor. Thus, a smaller DC-link capacitance can be used, lowering the cost and size of the AC...

  17. Zeroing Transformer's DC Current in Resonant Converters with No Series Capacitors

    E-Print Network [OSTI]

    Gertsman, Student Member, IEEE and Sam Ben-Yaakov ,Fellow, IEEE Power Electronics Laboratory Department: www.ee.bgu.ac.il/~pel Abstract - DC current unbalance in the windings of a transformer may initiate the transformer's DC current to zero by correcting the asymmetry of the drive. This balancing control

  18. Adjustable direct current and pulsed circuit fault current limiter

    DOE Patents [OSTI]

    Boenig, Heinrich J.; Schillig, Josef B.

    2003-09-23

    A fault current limiting system for direct current circuits and for pulsed power circuit. In the circuits, a current source biases a diode that is in series with the circuits' transmission line. If fault current in a circuit exceeds current from the current source biasing the diode open, the diode will cease conducting and route the fault current through the current source and an inductor. This limits the rate of rise and the peak value of the fault current.

  19. Horseshoes, Homoclinic Connections and Global Chaos in Current-Mode Controlled DC/DC

    E-Print Network [OSTI]

    Tse, Chi K. "Michael"

    , Japan Abstract-- In this paper, chaos in a current-mode controlled boost converter is studied. Firstly a rigorous proof of chaos in a current-mode controlled boost converter. This is done by proving the existence. Furthermore, we report homoclinic tangency and global chaos in the current-mode controlled boost converter. II

  20. 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)

    2009-04-14

    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.

  1. Sensorless Current Sharing in Digitally Controlled Two-Phase Buck DC-DC Converters

    E-Print Network [OSTI]

    is discussed. Experimental results are shown for a two-phase synchronous buck converter with 6V input voltage synchronous buck converter shown in Fig.1 has been built to test the proposed sensorless current sharing the digital command d. A sensorless current sharing block generates two command duty cycles d1 and d2 in order

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

    E-Print Network [OSTI]

    Shi, Meng

    2007-09-17

    , directly coupled inductors have the benefit of low sensitivity to input variation at high frequencies. In addition, the proposed new structure for multiphase DC-DC converters has excellent current sharing performance and reduced current ripple. Computer...

  3. Operation of the DC current transformer intensity monitors at FNAL during run II

    SciTech Connect (OSTI)

    Crisp, J.; Fellenz, B.; Heikkinen, D.; Ibrahim, M.A.; Meyer, T.; Vogel, G.; /Fermilab

    2012-01-01

    Circulating beam intensity measurements at FNAL are provided by five DC current transformers (DCCT), one per machine. With the exception of the DCCT in the Recycler, all DCCT systems were designed and built at FNAL. This paper presents an overview of both DCCT systems, including the sensor, the electronics, and the front-end instrumentation software, as well as their performance during Run II.

  4. Hybrid high direct current circuit interrupter

    DOE Patents [OSTI]

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

    1998-08-11

    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. Hybrid high direct current circuit interrupter

    DOE Patents [OSTI]

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

    1998-01-01

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

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

    E-Print Network [OSTI]

    Yancey, Billy Ferrall

    2011-08-08

    the voltage source doesn?t change polarity, current direction does not change, and a resistive load cannot generate power. Scenario?s 3 ? 6 also do not 36? ? make sense and this will be shown during the explanation of Scenario 2. Therefore only... earlier power transfer between source converters cannot occur because the voltage or current cannot change directions. In order to observe the behavior of this scenario the firing angle of the load was set at ?314 = 0?/180 ? and ?323 = 180...

  7. Dynamic magnetization states of a spin valve in the presence of dc and ac currents: Synchronization, modification, and chaos

    E-Print Network [OSTI]

    Li, Charles

    Dynamic magnetization states of a spin valve in the presence of dc and ac currents: Synchronization and numerical calculations of dynamic magnetization states of a spin valve in the presence of dc and ac currents are expected to appear. In this paper, we consider a simple spin valve as a model system to study the problem

  8. Optimization of Direct Current-Enhanced Radiofrequency Ablation: An Ex Vivo Study

    SciTech Connect (OSTI)

    Tanaka, Toshihiro, E-mail: toshihir@bf6.so-net.ne.jp; Isfort, Peter; Bruners, Philipp; Penzkofer, Tobias [RWTH Aachen University, Applied Medical Engineering, Helmholtz-Institute Aachen (Germany); Kichikawa, Kimihiko [Nara Medical University, Department of Radiology (Japan); Schmitz-Rode, Thomas; Mahnken, Andreas H. [RWTH Aachen University, Applied Medical Engineering, Helmholtz-Institute Aachen (Germany)

    2010-10-15

    The purpose of this study was to investigate the optimal setting for radiofrequency (RF) ablation combined with direct electrical current (DC) ablation in ex vivo bovine liver. An electrical circuit combining a commercially available RF ablation system with DC was developed. The negative electrode of a rectifier that provides DC was connected to a 3-cm multitined expandable RF probe. A 100-mH inductor was used to prevent electrical leakage from the RF generator. DC was applied for 15 min and followed by RF ablation in freshly excised bovine livers. Electric current was measured by an ammeter. Coagulation volume, ablation duration, and mean amperage were assessed for various DC voltages (no DC, 2.2, 4.5, and 9.0 V) and different RF ablation protocols (stepwise increase from 40 to 80 W, 40 W fixed, and 80 W fixed). Results were compared using Kruskal-Wallis and Mann-Whitney U test. Applying DC with 4.5 or 9.0 V, in combination with 40 W fixed or a stepwise increase of RF energy, resulted in significantly increased zone of ablation size compared with 2.2 V or no DC (P = 0.009). At 4.5 V DC, the stepwise increase of RF energy resulted in the same necrosis size as a 40 W fixed protocol (26.6 {+-} 3.9 vs. 26.5 {+-} 4.0 ml), but ablation duration was significantly decreased (296 {+-} 85 s vs. 423 {+-} 104 s; P = 0.028). Mean amperage was significantly lower at 4.5 V compared with 9.0 V (P = 0.028). Combining a stepwise increase of RF energy with a DC voltage of 4.5 V is most appropriate to increase coagulation volume and to minimize procedure time.

  9. Current Directions in Freight and Logistics Industry

    E-Print Network [OSTI]

    Minnesota, University of

    Current Directions in Freight and Logistics Industry CTS Freight and Logistics Symposium November- the-box #12;Perspective Be sure to look-up from time-to-time #12;Why Discuss Freight and Logistics....Large Part of the Economy Logistics Cost As A Percent of GDP ­ 10% Source: CSCMP State of Logistics 2007 #12

  10. Heating mode transition in a hybrid direct current/dual-frequency capacitively coupled CF{sub 4} discharge

    SciTech Connect (OSTI)

    Zhang, Quan-Zhi; Wang, You-Nian; Bogaerts, Annemie

    2014-06-14

    Computer simulations based on the particle-in-cell/Monte Carlo collision method are performed to study the plasma characteristics and especially the transition in electron heating mechanisms in a hybrid direct current (dc)/dual-frequency (DF) capacitively coupled CF{sub 4} discharge. When applying a superposed dc voltage, the plasma density first increases, then decreases, and finally increases again, which is in good agreement with experiments. This trend can be explained by the transition between the four main heating modes, i.e., DF coupling, dc and DF coupling, dc source dominant heating, and secondary electron dominant heating.

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

    DOE Patents [OSTI]

    Kotter, Dale K; Novack, Steven D

    2014-09-30

    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.

  12. Ferrosilicon smelting in a direct current furnace

    DOE Patents [OSTI]

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

    1992-12-29

    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.

  13. Ferrosilicon smelting in a direct current furnace

    DOE Patents [OSTI]

    Dosaj, Vishu D. (Midland, MI); May, James B. (Midland, MI)

    1992-12-29

    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.

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

    Open Energy Info (EERE)

    Direct-Current Resistivity Survey At Cove Fort Area (Warpinski, Et Al., 2002) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Direct-Current...

  15. Direct-Current Resistivity Survey At Beowawe Hot Springs Area...

    Open Energy Info (EERE)

    Direct-Current Resistivity Survey At Beowawe Hot Springs Area (Garg, Et Al., 2007) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Direct-Current...

  16. Direct-Current Resistivity Survey At Hualalai Northwest Rift...

    Open Energy Info (EERE)

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

  17. Direct-Current Resistivity Survey At Mauna Loa Southwest Rift...

    Open Energy Info (EERE)

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

  18. Direct-Current Resistivity Survey At Dixie Valley Geothermal...

    Open Energy Info (EERE)

    Direct-Current Resistivity Survey At Dixie Valley Geothermal Area (Laney, 2005) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Direct-Current...

  19. Direct-Current Resistivity At Beowawe Hot Springs Area (Garg...

    Open Energy Info (EERE)

    Direct-Current Resistivity At Beowawe Hot Springs Area (Garg, Et Al., 2007) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Direct-Current...

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

    Open Energy Info (EERE)

    Direct-Current Resistivity Survey At Lightning Dock Area (Cunniff & Bowers, 2005) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Direct-Current...

  1. Direct-Current Resistivity Survey At Kilauea Summit Area (Keller...

    Open Energy Info (EERE)

    Direct-Current Resistivity Survey At Kilauea Summit Area (Keller, Et Al., 1979) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Direct-Current...

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

    Open Energy Info (EERE)

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

  3. Direct-Current Resistivity Survey At Roosevelt Hot Springs Area...

    Open Energy Info (EERE)

    Direct-Current Resistivity Survey At Roosevelt Hot Springs Area (Combs 2006) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Direct-Current...

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

    Open Energy Info (EERE)

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

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

    Open Energy Info (EERE)

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

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

    Open Energy Info (EERE)

    Direct-Current Resistivity Survey At Nw Basin & Range Region (Pritchett, 2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Direct-Current...

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

    Open Energy Info (EERE)

    Direct-Current Resistivity Survey At Lightning Dock Area (Warpinski, Et Al., 2002) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Direct-Current...

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

    Open Energy Info (EERE)

    Direct-Current Resistivity At Central Nevada Seismic Zone Region (Pritchett, 2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Direct-Current...

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

    E-Print Network [OSTI]

    Moores, Gregory Lee

    1998-01-01

    on bare I8AWG solid copper electrodes in geometries simulating Sow current arcs, between wires of a typical cable bundle (1-6 amps and 12-125mils long). Using multiple linear regression the data was fitted to 18 different models, new or proposed...

  10. Direct-current cathodic vacuum arc system with magnetic-field mechanism for plasma stabilization

    SciTech Connect (OSTI)

    Zhang, H.-S.; Komvopoulos, K.

    2008-07-15

    Filtered cathodic vacuum arc (FCVA) deposition is characterized by plasma beam directionality, plasma energy adjustment via substrate biasing, macroparticle filtering, and independent substrate temperature control. Between the two modes of FCVA deposition, namely, direct current (dc) and pulsed arc, the dc mode yields higher deposition rates than the pulsed mode. However, maintaining the dc arc discharge is challenging because of its inherent plasma instabilities. A system generating a special configuration of magnetic field that stabilizes the dc arc discharge during film deposition is presented. This magnetic field is also part of the out-of-plane magnetic filter used to focus the plasma beam and prevent macroparticle film contamination. The efficiency of the plasma-stabilizing magnetic-field mechanism is demonstrated by the deposition of amorphous carbon (a-C) films exhibiting significantly high hardness and tetrahedral carbon hybridization (sp{sup 3}) contents higher than 70%. Such high-quality films cannot be produced by dc arc deposition without the plasma-stabilizing mechanism presented in this study.

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

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01

    AC vs. DC distribution: A loss comparison. Transmission andof a DC microgrid for residential houses. In Transmission &DC mainly because it enabled central generation and efficient long-distance power transmission.

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

    SciTech Connect (OSTI)

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

    2012-12-11

    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. Near Time-Optimal Transient Response in DC-DC Buck Converters Taking into Account the Inductor Current Limit

    E-Print Network [OSTI]

    for the controller design. Furthermore, the minimum number of switching actions required to handle a generic current Current Limit Amir Babazadeh, Luca Corradini, and Dragan Maksimovi Colorado Power Electronics Center ECEE of design equations is developed which provide the engineer with the necessary analytical tools

  14. Comparative study of zinc oxide and aluminum doped zinc oxide transparent thin films grown by direct current magnetron sputtering

    E-Print Network [OSTI]

    using direct current (dc) magnetron sputtering from pure metallic Zn and ceramic ZnO targets, as well of target composition on the film's surface topology, crystallinity, and optical transmission have been transmission and energy gap (Eg) of the metallic than of the ceramic target prepared films. © 2006 Elsevier B

  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, and high-density plasma in which energy of the incident ions is reduced;2,3 however, damage problems remain of a dc plasma reactor, and thus receives a large flux of low-energy electrons and hydrogen molecules

  16. 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

  17. 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.

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

    E-Print Network [OSTI]

    Tolbert, Leon M.

    - DC boost converter to boost the battery voltage for a traditional 3-phase inverter. The present HEV continuous power rating. Currently available power inverter systems for HEVs use a DC-DC boost converter power, the DC-DC boost converter is not needed and the battery voltage will be directly applied

  19. Interaction of Fast-Scale and Slow-Scale Bifurcations in Current-Mode Controlled DC/DC Converters

    E-Print Network [OSTI]

    Tse, Chi K. "Michael"

    of fast-scale and slow-scale bifurcations in the boost converter under current- mode control operating, and it manifests as period-doubling in the time scale, as reported in Iu et al. [7] for parallel boost converters, Wong et al. [8] for noise-coupled boost converters, and Wu et al. [9] for power

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

    SciTech Connect (OSTI)

    Liu, Fu-cheng; Yan, Wen; Wang, De-zhen

    2013-12-15

    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.

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

    SciTech Connect (OSTI)

    Long, W F

    1982-09-01

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

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

    Open Energy Info (EERE)

    Direct-Current Resistivity Survey At Blue Mountain Area (Fairbank Engineering Ltd, 2005) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity:...

  3. Direct-Current Resistivity Survey At Kilauea East Rift Geothermal...

    Open Energy Info (EERE)

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

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

    Open Energy Info (EERE)

    Direct-Current Resistivity Survey At Northern Basin & Range Region (Pritchett, 2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity:...

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

    Open Energy Info (EERE)

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

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

    Open Energy Info (EERE)

    Direct-Current Resistivity Survey At Walker-Lane Transitional Zone Region (Pritchett, 2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity:...

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

    Open Energy Info (EERE)

    Direct-Current Resistivity Survey At Valles Caldera - Redondo Geothermal Area (Wilt & Haar, 1986) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity:...

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

    Open Energy Info (EERE)

    2002) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Direct-Current Resistivity Survey At Cove Fort Area - Vapor (Warpinski, Et Al., 2002)...

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

    Open Energy Info (EERE)

    Direct-Current Resistivity Survey At Mt Princeton Hot Springs Area (Richards, Et Al., 2010) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity:...

  10. Direct-Current Resistivity Survey At Valles Caldera - Sulphur...

    Open Energy Info (EERE)

    Direct-Current Resistivity Survey At Valles Caldera - Sulphur Springs Geothermal Area (Wilt & Haar, 1986) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration...

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

    Open Energy Info (EERE)

    Direct-Current Resistivity Survey At Long Valley Caldera Geothermal Area (Pribnow, Et Al., 2003) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity:...

  12. Direct-Current Resistivity Survey At Kilauea East Rift Geothermal...

    Open Energy Info (EERE)

    Direct-Current Resistivity Survey At Kilauea East Rift Geothermal Area (FURUMOTO, 1976) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity:...

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

    Open Energy Info (EERE)

    Direct-Current Resistivity Survey At Central Nevada Seismic Zone Region (Pritchett, 2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity:...

  14. Auxiliary resonant DC tank converter

    DOE Patents [OSTI]

    Peng, Fang Z. (Knoxville, TN)

    2000-01-01

    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.

  15. Magnetic resonance visualization of conductive structures by sequence-triggered direct currents and spin-echo phase imaging

    SciTech Connect (OSTI)

    Eibofner, Frank; Wojtczyk, Hanne; Graf, Hansjörg E-mail: drGraf@t-online.de; Clasen, Stephan

    2014-06-15

    Purpose: Instrument visualization in interventional magnetic resonance imaging (MRI) is commonly performed via susceptibility artifacts. Unfortunately, this approach suffers from limited conspicuity in inhomogeneous tissue and disturbed spatial encoding. Also, susceptibility artifacts are controllable only by sequence parameters. This work presents the basics of a new visualization method overcoming such problems by applying sequence-triggered direct current (DC) pulses in spin-echo (SE) imaging. SE phase images allow for background free current path localization. Methods: Application of a sequence-triggered DC pulse in SE imaging, e.g., during a time period between radiofrequency excitation and refocusing, results in transient field inhomogeneities. Dependent on the additional z-magnetic field from the DC, a phase offset results despite the refocusing pulse. False spatial encoding is avoided by DC application during periods when read-out or slice-encoding gradients are inactive. A water phantom containing a brass conductor (water equivalent susceptibility) and a titanium needle (serving as susceptibility source) was used to demonstrate the feasibility. Artifact dependence on current strength and orientation was examined. Results: Without DC, the brass conductor was only visible due to its water displacement. The titanium needle showed typical susceptibility artifacts. Applying triggered DC pulses, the phase offset of spins near the conductor appeared. Because SE phase images are homogenous also in regions of persistent field inhomogeneities, the position of the conductor could be determined with high reliability. Artifact characteristic could be easily controlled by amperage leaving sequence parameters unchanged. For an angle of 30° between current and static field visualization was still possible. Conclusions: SE phase images display the position of a conductor carrying pulsed DC free from artifacts caused by persistent field inhomogeneities. Magnitude and phase images are acquired simultaneously under the same conditions without the use of extra measurement time. The presented technique offers many advantages for precise instrument localization in interventional MRI.

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

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01

    ballast fluorescent and LED lighting, which are DC- internalmotors [7]. Fluorescent and LED lighting uses one-quarter ofbest technology Lighting Incandescent, fluorescent, LED

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

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01

    motors [7]. Fluorescent and LED lighting uses one-quarter ofballast fluorescent and LED lighting, which are DC- internalbest technology Lighting Incandescent, fluorescent, LED

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

    SciTech Connect (OSTI)

    Cho, Sung Nae

    2013-04-15

    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.

  19. Investigation of helium ion production in constricted direct current plasma ion source with layered-glows

    SciTech Connect (OSTI)

    Lee, Yuna; Chung, Kyoung-Jae; Park, Yeong-Shin; Hwang, Y. S.; Center for Advance Research in Fusion Reactor Engineering, Seoul National University, Seoul 151-744

    2014-02-15

    Generation of helium ions is experimentally investigated with a constricted direct current (DC) plasma ion source operated at layered-glow mode, in which electrons could be accelerated through multiple potential structures so as to generate helium ions including He{sup 2+} by successive ionization collisions in front of an extraction aperture. The helium discharge is sustained with the formation of a couple of stable layers and the plasma ball with high density is created near the extraction aperture at the operational pressure down to 0.6 Torr with concave cathodes. The ion beam current extracted with an extraction voltage of 5 kV is observed to be proportional to the discharge current and inversely proportional to the operating pressure, showing high current density of 130 mA/cm{sup 2} and power density of 0.52 mA/cm{sup 2}/W. He{sup 2+} ions, which were predicted to be able to exist due to multiple-layer potential structure, are not observed. Simple calculation on production of He{sup 2+} ions inside the plasma ball reveals that reduced operating pressure and increased cathode area will help to generate He{sup 2+} ions with the layered-glow DC discharge.

  20. Simultaneous distribution of AC and DC power

    DOE Patents [OSTI]

    Polese, Luigi Gentile

    2015-09-15

    A system and method for the transport and distribution of both AC (alternating current) power and DC (direct current) power over wiring infrastructure normally used for distributing AC power only, for example, residential and/or commercial buildings' electrical wires is disclosed and taught. The system and method permits the combining of AC and DC power sources and the simultaneous distribution of the resulting power over the same wiring. At the utilization site a complementary device permits the separation of the DC power from the AC power and their reconstruction, for use in conventional AC-only and DC-only devices.

  1. Direct Catalytic Upgrading of Current Dilute Alcohol Fermentation...

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

    Direct Catalytic Upgrading of Current Dilute Alcohol Fermentation Streams to Hydrocarbons for Fungible Fuels 2.3.1.100 Chaitanya Narula, 1 Zhenglong Li, 1 E. Casbeer, 1 Robert A....

  2. Electro-optically responsive composites of gold nanospheres in 5CB liquid crystal under direct current and alternating current joint action

    SciTech Connect (OSTI)

    Hadjichristov, Georgi B.; Marinov, Yordan G.; Petrov, Alexander G.; Bruno, Emanuela; Marino, Lucia; Scaramuzza, Nicola

    2014-02-28

    Direct current (DC) electro-optical (EO) control of transmitted laser beam intensity based on EO controlled coherent light scattering and diffraction by stationary longitudinal texture pattern (LTP) is achieved in planar-oriented cells with a composite mixture of polymer-coated gold spherical nanoparticles (Au-NPs) with a mean diameter of about 12?nm and the room-temperature nematic pentylcyanobiphenyl (5CB). At relatively low DC voltage of about 5 V, the effective scattering/diffraction by Au-NPs/5CB composites leads to a spatial spreading of transmitted coherent light from a low-power continuous wave laser beam, resulting in a drastic reduction of its local intensity. The effect is polarization dependent and is strongest when the polarization of the input laser beam is along the LTP. The EO response of Au-NPs/5CB mixtures is studied under DC and alternating current (AC) joint action with the aim of the potential use of these composite materials as EO controlled diffusers. The specific V-shaped sharp dip in the DC voltage-dependent coherent light transmittance of Au-NPs/5CB planar films, as well as the possibility for erasing the scattering/diffractive LTP in the films by joint low AC voltage, can be useful for EO applications in the field of process control and for detection of weak dynamic electric fields.

  3. DC attenuation meter

    DOE Patents [OSTI]

    Hargrove, Douglas L.

    2004-09-14

    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.

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

    SciTech Connect (OSTI)

    Schweigert, I. V.; George Washington University, Washington, DC 20052 ; Kaganovich, I. D.; Demidov, V. I.; St. Petersburg State University, St. Petersburg

    2013-10-15

    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.

  5. Lung, Artificial: Current Research and Future Directions William J. Federspiel

    E-Print Network [OSTI]

    Federspiel, William J.

    Lung, Artificial: Current Research and Future Directions William J. Federspiel Robert G. Svitek University of Pittsburgh, Pittsburgh, Pennsylvania, U.S.A. INTRODUCTION Artificial lungs are medical devices designed to take over or supplement the respiratory function of the lung: oxygenating the blood

  6. Transformer coupling for transmitting direct current through a barrier

    DOE Patents [OSTI]

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

    1987-06-29

    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.

  7. 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)

    1988-01-01

    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.

  8. Comparison of direct current and 50?Hz alternating current microscopic corona characteristics on conductors

    SciTech Connect (OSTI)

    Zhang, Shuai Zhang, Bo He, Jinliang

    2014-06-15

    Corona discharge is one of the major design factors for extra-high voltage and ultra-high voltage DC/AC transmission lines. Under different voltages, corona discharge reveals different characteristics. This paper aims at investigating DC and AC coronas on the microscopic scale. To obtain the specific characteristics of DC and AC coronas, a new measurement approach that utilizes a coaxial wire-cylinder corona cage is designed in this paper, and wires of different diameters are used in the experiment. Based on the measurements, the respective microscopic characteristics of DC and AC coronas are analyzed and compared. With differences in characteristics between DC and AC coronas proposed, this study provides useful insights into DC/AC corona discharges on transmission line applications.

  9. Design, Assembly, and Commissioning of a Cryogenic DC Current Transformer Designed for Measuring Currents of up to 80 kA

    E-Print Network [OSTI]

    Montenero, G; Bottura, L; Arpaia, P

    2015-01-01

    A new cryogenic dc current transformer (Cryo-DCCT) has recently been designed and assembled at CERN. The device, whose design is based on that of a high-accuracy 600 A market solution suitable for room temperature applications, is optimized for measuring currents of up to 80 kA and for operation at 4.2 K. The CryoDCCT has been conceived with the objective of preserving the metrological performance of the original commercial device in the new extended range of operation. For reducing the effect of interfering magnetic fields arising from test conditions, it incorporates ferromagnetic and MgB2 superconducting shields. In this paper, the design of the CryoDCCT and the results of the commissioning of the device at CERN are reported. The effectiveness of the current transducer is analysed and discussed. This new device will be used for measuring the secondary current of a 80 kA superconducting transformer feeding a sample of NbSn3 cable at the Facility for Research on Superconducting Cables (FRESCA) at CERN.

  10. UConn PhysicsBarrett O. Wells Zero resistance to dc current

    E-Print Network [OSTI]

    Alpay, S. Pamir

    Westborough, MA Ship Propulsion SuperVAR Power Grid Regulation Wind Power power conversion and grid connection of matter (like ice vs water) but of electrons · Occurs below a critical temperature TC, current density JC Commercial power distribution, Holbrook, NY #12;UConn PhysicsBarrett O. Wells Superconducting Magnet Energy

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

    SciTech Connect (OSTI)

    J.L. Morrison

    2014-08-01

    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.

  12. Argon metastable dynamics and lifetimes in a direct current microdischarge

    SciTech Connect (OSTI)

    Stefanovi?, Ilija; Kuschel, Thomas; Schröter, Sandra; Böke, Marc

    2014-09-21

    In this paper we study the properties of a pulsed dc microdischarge with the continuous flow of argon. Argon metastable lifetimes are measured by tunable diode laser absorption spectroscopy (TDLAS) and are compared with calculated values which yield information about excitation and de-excitation processes. By increasing the gas flow-rate about 5 times from 10 to 50 sccm, the Ar{sup m} lifetime increases from 1 to 5 ?s due to the reduction of metastable quenching with gas impurities. Optical emission spectroscopy reveals nitrogen and water molecules as the main gas impurities. The estimated N? density [N?]=0.1% is too low to explain the measured metastable lifetimes. Water impurity was found to be the main de-excitation source of argon metastable atoms due to high quenching coefficients. The water impurity level of [H?O]=0.15% to 1% is sufficient to bring calculated metastable lifetimes in line with experiments. The maximum value of water content in the discharge compared to the argon atoms is estimated to approximately 6%, due to the large surface to volume ratio of the microdischarge. The current pulse releases the water molecules from the electrode surface and they are either re-adsorbed in the time between 0.4 ms for [H?O]=1% and 2.6 ms for [H?O]=0.15% or pumped out of the discharge with the speed equal to the gas flow-rate. Depending on its partial pressure, the water impurity re-adsorption time is of the order of magnitude or less then the argon gas residence time.

  13. Building Scale DC Microgrids

    E-Print Network [OSTI]

    Marnay, Chris

    2014-01-01

    involves DC directly, e.g. fuel cells, fuels, but electricthe likely emergence of fuel cells and required batteriesphotovoltaic cells, fuel cells, power quality, converters,

  14. 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 ...

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

    DOE Patents [OSTI]

    Moyers, J.C.; Haynes, H.D.

    1996-12-10

    A method for determining the position of an armature of a dc-powered solenoid is disclosed. 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. 5 figs.

  16. 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)

    1996-12-10

    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.

  17. Development and evaluation of an implantable chronic DC stimulation and measurement probe for nerve regeneration studies 

    E-Print Network [OSTI]

    Macha, Douglas Bryan

    1995-01-01

    isotropic. The actual field strength or current density induced by the applied current is seldom directly measured in-vivo. This research seeks to evaluate the design of an implantable DC stimulator capable of delivering a constant, stable and measurable...

  18. Catalog of DC Appliances and Power Systems

    SciTech Connect (OSTI)

    Garbesi, Karina; Vossos, Vagelis; Shen, Hongxia

    2010-10-13

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

  19. Direct-Current Resistivity At Cove Fort Area (Warpinski, Et Al...

    Open Energy Info (EERE)

    Direct-Current Resistivity At Cove Fort Area (Warpinski, Et Al., 2002) (Redirected from Direct-Current Resistivity At Cove Fort Area - Vapor (Warpinski, Et Al., 2002)) Jump to:...

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

    SciTech Connect (OSTI)

    Nur, Adrian; Rahmawati, Alifah; Ilmi, Noor Izzati; Affandi, Samsudin; Widjaja, Arief

    2014-02-24

    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.

  1. 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. Goswami, K. S.; Saikia, B. K.

    2014-03-15

    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.

  2. DIRECT-DRIVE AND EDDY-CURRENT SEPTUM MAGNETS June 29, 2001

    E-Print Network [OSTI]

    Kemner, Ken

    DIRECT-DRIVE AND EDDY-CURRENT SEPTUM MAGNETS S. H. Kim June 29, 2001 Abstract -- Two types of thin septum magnets, direct drive and eddy current, were compared mainly in 2-D magnetic aspects. For the eddy-current type, the leakage fields calculated using OPERA-2d were compared with the calculations

  3. Deep Trench Capacitor based Step-up and Step-down DC/DC Converters in 32nm SOI with Opportunistic

    E-Print Network [OSTI]

    Sapatnekar, Sachin

    Deep Trench Capacitor based Step-up and Step-down DC/DC Converters in 32nm SOI with Opportunistic domains. Using ultra-high density deep trench capacitors, we are able to achieve an output power density-power domain scenario by implementing a bi-directional opportunistic current borrowing scheme. Deep trench

  4. Direct current sputtering of boron from boron/coron mixtures

    DOE Patents [OSTI]

    Timberlake, John R. (Allentown, NJ); Manos, Dennis (Williamsburg, VA); Nartowitz, Ed (Edison, NJ)

    1994-01-01

    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.

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

    DOE Patents [OSTI]

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

    1994-12-13

    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.

  6. Multilevel DC link inverter

    DOE Patents [OSTI]

    Su, Gui-Jia

    2003-06-10

    A multilevel DC link inverter and method for improving torque response and current regulation in permanent magnet motors and switched reluctance motors having a low inductance includes a plurality of voltage controlled cells connected in series for applying a resulting dc voltage comprised of one or more incremental dc voltages. The cells are provided with switches for increasing the resulting applied dc voltage as speed and back EMF increase, while limiting the voltage that is applied to the commutation switches to perform PWM or dc voltage stepping functions, so as to limit current ripple in the stator windings below an acceptable level, typically 5%. Several embodiments are disclosed including inverters using IGBT's, inverters using thyristors. All of the inverters are operable in both motoring and regenerating modes.

  7. Multiple solutions in the theory of direct current glow discharges: Effect of plasma chemistry and nonlocality, different plasma-producing gases, and 3D modelling

    SciTech Connect (OSTI)

    Almeida, P. G. C.; Benilov, M. S.

    2013-10-15

    The work is aimed at advancing the multiple steady-state solutions that have been found recently in the theory of direct current (DC) glow discharges. It is shown that an account of detailed plasma chemistry and non-locality of electron transport and kinetic coefficients results in an increase of the number of multiple solutions but does not change their pattern. Multiple solutions are shown to exist for discharges in argon and helium provided that discharge pressure is high enough. This result indicates that self-organization in DC glow microdischarges can be observed not only in xenon, which has been the case until recently, but also in other plasma-producing gases; a conclusion that has been confirmed by recent experiments. Existence of secondary bifurcations can explain why patterns of spots grouped in concentric rings, observed in the experiment, possess in many cases higher number of spots in outer rings than in inner ones.

  8. Parametric Study of PV Arc-Fault Generation Methods and Analysis of Conducted DC Spectrum

    E-Print Network [OSTI]

    Parametric Study of PV Arc-Fault Generation Methods and Analysis of Conducted DC Spectrum Jay photovoltaic (PV) direct current (DC) arc- fault detectors use the frequency content of the PV system to detect by different PV arcs in the field. In this investigation, we (a) discuss the differences in establishing

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

    E-Print Network [OSTI]

    Kaganovich, Igor

    Active electron energy distribution function control in direct current discharge using an auxiliary://pop.aip.org/authors #12;Active electron energy distribution function control in direct current discharge using; accepted 18 July 2013; published online 10 October 2013) The electron energy distribution functions

  10. 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

    2014-12-11

    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.

  11. Differences between direct current and alternating current capacitance nonlinearities in high-k dielectrics and their relation to hopping conduction

    SciTech Connect (OSTI)

    Khaldi, O.; Kassmi, M.; Gonon, P. Vallée, C.; Mannequin, C.; Sylvestre, A.; Jomni, F.

    2014-08-28

    Capacitance nonlinearities were studied in atomic layer deposited HfO{sub 2} films using two types of signals: a pure ac voltage of large magnitude (ac nonlinearities) and a small ac voltage superimposed to a large dc voltage (dc nonlinearities). In theory, ac and dc nonlinearities should be of the same order of magnitude. However, in practice, ac nonlinearities are found to be an order of magnitude higher than dc nonlinearities. Besides capacitance nonlinearities, hopping conduction is studied using low-frequency impedance measurements and is discussed through the correlated barrier hopping model. The link between hopping and nonlinearity is established. The ac nonlinearities are ascribed to the polarization of isolated defect pairs, while dc nonlinearities are attributed to electrode polarization which originates from defect percolation paths. Both the ac and dc capacitance nonlinearities display an exponential variation with voltage, which results from field-induced lowering of the hopping barrier energy.

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

    E-Print Network [OSTI]

    Zhao, Tianshou

    2007-01-01

    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 did the cell having the conventional perforated-plate current collector with high methanol

  13. Cathode fall model and current-voltage characteristics of field emission driven direct current microplasmas

    SciTech Connect (OSTI)

    Venkattraman, Ayyaswamy

    2013-11-15

    The post-breakdown characteristics of field emission driven microplasma are studied theoretically and numerically. A cathode fall model assuming a linearly varying electric field is used to obtain equations governing the operation of steady state field emission driven microplasmas. The results obtained from the model by solving these equations are compared with particle-in-cell with Monte Carlo collisions simulation results for parameters including the plasma potential, cathode fall thickness, ion number density in the cathode fall, and current density vs voltage curves. The model shows good overall agreement with the simulations but results in slightly overpredicted values for the plasma potential and the cathode fall thickness attributed to the assumed electric field profile. The current density vs voltage curves obtained show an arc region characterized by negative slope as well as an abnormal glow discharge characterized by a positive slope in gaps as small as 10 ?m operating at atmospheric pressure. The model also retrieves the traditional macroscale current vs voltage theory in the absence of field emission.

  14. Quantum transport in a driven disordered potential: onset of directed current and noise-induced current reversal

    E-Print Network [OSTI]

    Denis Makarov; Leonid Kon'kov

    2015-02-06

    We study motion of a quantum wavepacket in a one-dimensional potential with correlated disorder. Presence of long-range potential correlations allows for existence of both localized and extended states. Weak time-dependent perturbation in the form of a fluctuating plane wave is superimposed onto the potential. This model can be realized in experiments with optically trapped cold atoms. Time-dependent perturbation causes transitions between localized and extended states. Owing to violation of space-time symmetries, there arises atomic current which is codirectional with the wave-like perturbation. However, it is shown that the perturbation can drag atoms only within some limited time interval, and then the current changes its direction. Increasing of the perturbation bandwidth and/or amplitude results in decreasing of the time of current reversal. We argue that onset of the current reversal is associated with inhomogeneity of diffusion in the momentum space.

  15. Alternating and direct current field effects on the structure-property relationships in Na{sub 0.5}Bi{sub 0.5}TiO{sub 3}-x%BaTiO{sub 3} textured ceramics

    SciTech Connect (OSTI)

    Ge, Wenwei; Li, Jiefang; Viehland, D.; Maurya, Deepam; Priya, Shashank

    2013-06-03

    The influence of alternating (ac) and direct current (dc) fields on the structural and dielectric properties of [001]{sub PC} textured Na{sub 0.5}Bi{sub 0.5}TiO{sub 3}-7%BaTiO{sub 3} (NBT-7%BT) ceramics has been investigated. X-ray diffraction measurements revealed that the depolarization at temperature T{sub d} in poled samples resulted from a tetragonal {yields} pseudo-cubic transition on heating. Moderate ac drive and dc bias had opposite influences on T{sub d}: ac drive decreased the T{sub d}, whereas dc bias increased it. These investigations suggested an effective method to expand the working temperature range of NBT-x%BT textured ceramics to a high temperature.

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

    SciTech Connect (OSTI)

    Wörner, L.; Groupe de Recherches sur l'Energétique des Milieux Ionisés, UMR7344, CNRS, Univ. Orléans, F-45067 Orléans ; Ivlev, A. V.; Huber, P.; Hagl, T.; Thomas, H. M.; Morfill, G. E.; Couëdel, L.; Schwabe, M.; Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, California 94720 ; Mikikian, M.; Boufendi, L.; Skvortsov, A.; Lipaev, A. M.; Molotkov, V. I.; Petrov, O. F.; Fortov, V. E.

    2013-12-15

    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.

  17. Perturbation of the cathode fall in direct-current glow discharges by particulate contamination

    E-Print Network [OSTI]

    Kushner, Mark

    Perturbation of the cathode fall in direct-current glow discharges by particulate contamination July 1991; accepted for publication 19 September 1991) Particulate (or "dust") contamination of plasma by dust contamination. We find that at constant current densities, the plasma responds to the reduction

  18. Modeling and Control of Unmanned Aerial Vehicles Current Status and Future Directions

    E-Print Network [OSTI]

    Antsaklis, Panos

    Modeling and Control of Unmanned Aerial Vehicles ­ Current Status and Future Directions George have highlighted the potential utility for Unmanned Aerial Vehicles (UAVs). Both fixed wing and rotary Reimann, Panos Antsaklis, Kimon Valavanis, "Modeling and Control of Unmanned Aerial Vehicles­ Current

  19. First-cut design of an all-superconducting 100-T direct current magnet

    SciTech Connect (OSTI)

    Iwasa, Yukikazu Hahn, Seungyong

    2013-12-16

    A 100-T magnetic field has heretofore been available only in pulse mode. This first-cut design demonstrates that a 100-T DC magnet (100?T) is possible. We base our design on: Gadolinium-based coated superconductor; a nested-coil formation, each a stack of double-pancake coils with the no-insulation technique; a band of high-strength steel over each coil; and a 12-T radial-field limit. The 100?T, a 20?mm cold bore, 6-m diameter, 17-m height, with a total of 12?500-km long superconductor, stores an energy of 122 GJ at its 4.2-K operating current of 2400?A. It requires a 4.2-K cooling power of 300?W.

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

    E-Print Network [OSTI]

    Ljubljana, University of

    1994-01-01

    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

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

    SciTech Connect (OSTI)

    Litzenberger, Wayne; Lava, Val

    1994-08-01

    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).

  2. DC arc weld starter

    DOE Patents [OSTI]

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

    1990-01-01

    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.

  3. Multi-Level DC/DC Power Conversion System with Multiple DC Sources

    E-Print Network [OSTI]

    Tolbert, Leon M.

    boost converter. Experimental results are provided to confirm the analysis and control concept. I, instead of connecting all batteries in series as one power source and a bi-directional boost converter. INTRODUCTION Traditional dc/dc converters require at least one inductive component, which is bulky, heavy

  4. Measurement and on-chip control of a niobium persistent current qubit

    E-Print Network [OSTI]

    Crankshaw, Donald S. (Donald Shane), 1974-

    2003-01-01

    The persistent current qubit is a superconducting ring interrupted by three Josephson junctions. Its two quantum states have circulating currents in opposite directions which can be measured by a dc SQUID magnetometer. ...

  5. Census Snapshot: Washington, DC

    E-Print Network [OSTI]

    Romero, Adam P.; Baumle, Amanda K; Badgett, M.V. Lee; Gates, Gary J

    2007-01-01

    INSTITUTE CENSUS SNAPSHOT | WASHINGTON, DC. | DECEMBER 2007WASHINGTON, D.C. Adam P. Romero, Public Policy Fellow AmandaINSTITUTE CENSUS SNAPSHOT | WASHINGTON, DC. | DECEMBER 2007

  6. Direct current injection and thermocapillary flow for purification of aligned arrays of single-walled carbon nanotubes

    E-Print Network [OSTI]

    Rogers, John A.

    Direct current injection and thermocapillary flow for purification of aligned arrays of single://scitation.aip.org/termsconditions. Downloaded to ] IP: 192.17.15.215 On: Tue, 07 Apr 2015 15:52:18 #12;Direct current injection nanotube aqueous dispersions Appl. Phys. Lett. 103, 133114 (2013); 10.1063/1.4823541 Directed assembly

  7. Direct measurement of the characteristic three-body electron attachment time in the atmospheric air in direct current electric field

    SciTech Connect (OSTI)

    Shutov, A. V.; Smetanin, I. V.; Ionin, A. A.; Levchenko, A. O.; Seleznev, L. V.; Sinitsyn, D. V.; Ustinovskii, N. N.; Zvorykin, V. D.

    2013-07-15

    We report the results of theoretical and experimental study of the characteristic time for three-body attachment of electrons produced by 100 fs UV laser pulse in the atmosphere air in the external DC electric field ranged from 0.2 to 10 kV/cm.

  8. Catalog of DC Appliances and Power Systems

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01

    sited renewable energy market for the foreseeable future. Inup renewable energy systems increases in the future, chargerenewable energy sources [5]. If direct-DC has a future in

  9. Producing a Radioactive Source in a Deuterated Palladium Electrode Under Direct-Current Glow Discharge

    SciTech Connect (OSTI)

    Yamada, Hiroshi; Uchiyama, Kazuyoshi; Kawata, Nobuhiko; Kurisawa, Yoshiyuki; Nakamura, Mitsuru

    2001-03-15

    Anomalous gamma emission was rarely observed during direct-current glow discharge in {approx}3 Torrs of deuterium gas using a deuterated palladium foil cathode. Autoradiography after the discharge experiment showed that isotopes with low- and high-energy radiation components were produced before or during the discharge. The palladium foil after the anomalous gamma-ray emission was analyzed by secondary ion mass spectroscopy, which revealed a considerable increase in the content of iron and copper on the surface.

  10. Glow-to-arc transition events in H{sub 2}-Ar direct current pulsed plasma: Automated measurement of current and voltage

    SciTech Connect (OSTI)

    Mendes, Luciano A.; Rodrigues, Jhonatam C.; Mafra, Marcio

    2012-01-15

    The glow-to-arc transition phenomena (arcing) observed in plasma reactors used in materials processing was studied through the arcs characteristic current and voltage waveforms. In order to capture these arcs signals, a LABVIEW based automated instrumentation system (ARCVIEW) was developed, including the integration of an oscilloscope equipped with proper current and voltage probes. The system also allows capturing the process parameters at the arc occurrence moments, which were used to map the arcs events conditions. Experiments in H{sub 2}-Ar DC pulsed plasma returned signals data from 215 arcs events, which were analyzed through software routines. According to the results, an anti-arcing system should react in the time order of few microseconds to prevent most of the damage caused by the undesired arcing phenomena.

  11. A single-inductor switching DC-DC converter with five outputs and ordered power-distributive control

    E-Print Network [OSTI]

    Le, Hanh-Phuc; Chae, Chang-Seok; Lee, Kwang-Chan; Wang, Se-Won; Cho, Gyu-Ha; Cho, Gyu-Hyeong

    2007-01-01

    integrated current mode boost converter in standard 3.3=5-Vef?ciency CMOS DC-DC boost converter with current sensingdeveloping reset ICs, boost converters for PM OLED, and SIMO

  12. The physical nature of the phenomenon of positive column plasma constriction in low-pressure noble gas direct current discharges

    SciTech Connect (OSTI)

    Kurbatov, P. F.

    2014-02-15

    The essence of the positive-column plasma constriction for static (the diffusion mode) and dynamic ionization equilibrium (the stratificated and constricted modes) is analyzed. Two physical parameters, namely, the effective ionization rate of gas atoms and the ambipolar diffusion coefficient of electrons and ions, determine the transverse distribution of discharge species and affect the current states of plasma. Transverse constriction of the positive column takes place as the gas ionization level (discharge current) and pressure increase. The stratified mode (including the constricted one) is observed between the two adjacent types of self-sustained discharge phases when they coexist together at the same time or in the same place as a coherent binary mixture. In the case, a occurrence of the discharge phase with more high electron density presently involve a great decrease in the cross-section of the current channel for d.c. discharges. Additional physical factors, such as cataphoresis and electrophoresis phenomena and spatial gas density inhomogeneity correlated with a circulatory flow in d.c. discharges, are mainly responsible for the current hysteresis and partially constricted discharge.

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

    DOE Patents [OSTI]

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

    1998-06-30

    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.

  14. Detrapping of tungsten nanoparticles in a direct-current argon glow discharge

    SciTech Connect (OSTI)

    Couëdel, L. Kumar, K. Kishor; Arnas, C.

    2014-12-15

    Nanoparticles are grown from the sputtering of a tungsten cathode in a direct current argon glow discharge. Laser light scattering of a vertical laser sheet going through the plasma reveals that the dust particle cloud is compressed and pushed towards the anode during the discharge. Scanning electron microscopy images of substrates exposed to the plasma for given durations show that dust particles are continuously falling down on the anode during the discharge. These observations are explained by the fact that the electrostatic force at the negative glow-anode sheath boundary cannot balance the ion drag, gravity, and thermophoresis forces for particles of more than a few tens of nanometres in diameter.

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

    DOE Patents [OSTI]

    Su, Gui-Jia (Knoxville, TN)

    2008-08-05

    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.

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

    SciTech Connect (OSTI)

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

    2012-10-09

    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.

  17. Synthesis of silicon nanotubes by DC arc plasma method

    SciTech Connect (OSTI)

    Tank, C. M.; Bhoraskar, S. V.; Mathe, V. L.

    2012-06-05

    Plasma synthesis is a novel technique of synthesis of nanomaterials as they provide high rate of production and promote metastable reactions. Very thin walled silicon nanotubes were synthesized in a DC direct arc thermal plasma reactor. The effect of parameters of synthesis i.e. arc current and presence of hydrogen on the morphology of Si nanoparticles is reported. Silicon nanotubes were characterized by Transmission Electron Microscopy (TEM), Local Energy Dispersive X-ray analysis (EDAX), and Scanning Tunneling Microscopy (STM).

  18. Current sensor

    DOE Patents [OSTI]

    Yakymyshyn, Christopher Paul; Brubaker, Michael Allen; Yakymyshyn, Pamela Jane

    2007-01-16

    A current sensor is described that uses a plurality of magnetic field sensors positioned around a current carrying conductor. The sensor can be hinged to allow clamping to a conductor. The current sensor provides high measurement accuracy for both DC and AC currents, and is substantially immune to the effects of temperature, conductor position, nearby current carrying conductors and aging.

  19. Radio frequency dc-dc power conversion

    E-Print Network [OSTI]

    Rivas, Juan, 1976-

    2007-01-01

    THIS THESIS addresses the development of system architectures and circuit topologies for dc-dc power conversion at very high frequencies. The systems architectures that are developed are structured to overcome limitations ...

  20. Building Scale DC Microgrids

    E-Print Network [OSTI]

    Marnay, Chris

    2013-01-01

    however, DC was less amenable to transmission over longtransmission 32 km to Buffalo, even though the loads at that time were entirely DC.

  1. Building Scale DC Microgrids

    E-Print Network [OSTI]

    Marnay, Chris

    2014-01-01

    ABORATORY Building Scale DC Microgrids Chris Marnay, Stevenemployer. Building Scale DC Microgrids Chris Marnay, IEEEgenerally known as microgrids (or µgrids). The dominance of

  2. Mapping of top of permafrost using a direct current resistivity survey

    SciTech Connect (OSTI)

    Gilmore, T.J.; Clayton, E.A.

    1995-10-01

    Data from a direct current resistivity survey and geologic logs from boreholes were used to map the top of permafrost at a remote Air Force installation in Alaska. This study resulted from a remedial investigation that was conducted at Eielson Air Force base near Fairbanks, Alaska under the federal Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) regulations. The depth and continuity of the permafrost was important in determining the fate of petroleum contamination that was inadvertently discharged to the ground during earlier Air Force operations. The results indicate that the top of permafrost forms a highly irregular surface. In general, however, the top of permafrost forms a diagonal ridge at the center of the contour grid that is bordered on each side by troughs.

  3. Scaling law for direct current field emission-driven microscale gas breakdown

    SciTech Connect (OSTI)

    Venkattraman, A.; Alexeenko, A. A.

    2012-12-15

    The effects of field emission on direct current breakdown in microscale gaps filled with an ambient neutral gas are studied numerically and analytically. Fundamental numerical experiments using the particle-in-cell/Monte Carlo collisions method are used to systematically quantify microscale ionization and space-charge enhancement of field emission. The numerical experiments are then used to validate a scaling law for the modified Paschen curve that bridges field emission-driven breakdown with the macroscale Paschen law. Analytical expressions are derived for the increase in cathode electric field, total steady state current density, and the ion-enhancement coefficient including a new breakdown criterion. It also includes the effect of all key parameters such as pressure, operating gas, and field-enhancement factor providing a better predictive capability than existing microscale breakdown models. The field-enhancement factor is shown to be the most sensitive parameter with its increase leading to a significant drop in the threshold breakdown electric field and also to a gradual merging with the Paschen law. The proposed scaling law is also shown to agree well with two independent sets of experimental data for microscale breakdown in air. The ability to accurately describe not just the breakdown voltage but the entire pre-breakdown process for given operating conditions makes the proposed model a suitable candidate for the design and analysis of electrostatic microscale devices.

  4. Design of a step-down DC-DC controller integrated circuit with adaptive dead-time control

    E-Print Network [OSTI]

    Li, Zhipeng, M. Eng. Massachusetts Institute of Technology

    2010-01-01

    A constant-frequency peak current mode synchronous step-down DC-DC controller integrated circuit has been designed with adaptive dead-time control. The adaptive dead-time control circuitry is implemented as digital ...

  5. Quantum states and linear response in dc and electromagnetic fields for charge current and spin polarization of electrons at Bi/Si interface with giant spin-orbit coupling

    E-Print Network [OSTI]

    Khomitsky, D V

    2011-01-01

    An expansion of the nearly free-electron model constructed by Frantzeskakis, Pons and Grioni [Phys. Rev. B {\\bf 82}, 085440 (2010)] describing quantum states at Bi/Si(111) interface with giant spin-orbit coupling is developed and applied for the band structure and spin polarization calculation, as well as for the linear response analysis for charge current and induced spin caused by dc field and by electromagnetic radiation. It is found that the large spin-orbit coupling in this system may allow resolving the spin-dependent properties even at room temperature and at realistic collision rate. The geometry of the atomic lattice combined with spin-orbit coupling leads to an anisotropic response both for current and spin components related to the orientation of the external field. The in-plane dc electric field produces only the in-plane components of spin in the sample while both the in-plane and out-of-plane spin components can be excited by normally propagating electromagnetic wave with different polarizations...

  6. Quantum states and linear response in dc and electromagnetic fields for charge current and spin polarization of electrons at Bi/Si interface with giant spin-orbit coupling

    E-Print Network [OSTI]

    D. V. Khomitsky

    2011-05-21

    An expansion of the nearly free-electron model constructed by Frantzeskakis, Pons and Grioni [Phys. Rev. B {\\bf 82}, 085440 (2010)] describing quantum states at Bi/Si(111) interface with giant spin-orbit coupling is developed and applied for the band structure and spin polarization calculation, as well as for the linear response analysis for charge current and induced spin caused by dc field and by electromagnetic radiation. It is found that the large spin-orbit coupling in this system may allow resolving the spin-dependent properties even at room temperature and at realistic collision rate. The geometry of the atomic lattice combined with spin-orbit coupling leads to an anisotropic response both for current and spin components related to the orientation of the external field. The in-plane dc electric field produces only the in-plane components of spin in the sample while both the in-plane and out-of-plane spin components can be excited by normally propagating electromagnetic wave with different polarizations.

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

    SciTech Connect (OSTI)

    2012-01-30

    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.

  8. Voltages across assembly joints due to direct-strike lightning currents

    SciTech Connect (OSTI)

    Dinallo, M.S. [Quatro Corp., Albuquerque, NM (United States); Fisher, R.J. [Sandia National Labs., Albuquerque, NM (United States)

    1994-08-01

    An extensive set of direct-strike lightning tests has been carried out on a set of facsimile assembly joints of the kinds employed in the design of nuclear weapon cases. Taken as a whole, the test hardware included all the conceptual design elements that are embodied, either singly or in combination, in any specific assembly joint incorporated into any stockpiled weapon. During the present testing, the effects of all key design parameters on the voltages developed across the interior of the joints were investigated under a range of lightning stroke current parameter values. Design parameter variations included the types and number of joint fasteners, mechanical preload, surface finish tolerance and coatings, and the material from which the joint assembly was fabricated. Variations of the simulated lightning stroke current included amplitude (30-, 100-, and 200-kA peak), rise time, and decay time. The maximum voltage observed on any of the test joints that incorporated proper metal-to-metal surface contact was 65 V. Typical response values were more on the order of 20 V. In order to assess the effect of the presence of a dielectric coating (either intentional or as a result of corrosion) between the mating surfaces of a joint, a special configuration was tested in which the mating parts of the test assembly were coated with a 1-mil-thick dielectric anodizing layer. First strokes to these test assemblies resulted in very narrow voltage spikes of amplitudes up to 900 V. The durations of these spikes were less than 0.1 {mu}s. However, beyond these initial spikes, the voltages typically had amplitudes of up to 400 V for durations of 3 to 5 {mu}s.

  9. 936 IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS, VOL. 50, NO. 5, OCTOBER 2003 Gain Adaptation of Networked DC Motor Controllers

    E-Print Network [OSTI]

    Chow, Mo-Yuen

    ) milling machine, dc motors can be connected to controllers, drivers and sensors by directly wiring

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

    SciTech Connect (OSTI)

    Demidov, V. I.; Kudryavtsev, A. A.; Stepanova, O. M.; Kurlyandskaya, I. P.

    2014-09-15

    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. Open-air direct current plasma jet: Scaling up, uniformity, and cellular control

    SciTech Connect (OSTI)

    Wu, S.; Wang, Z.; Huang, Q.; Lu, X.; Ostrikov, K.

    2012-10-15

    Atmospheric-pressure plasma jets are commonly used in many fields from medicine to nanotechnology, yet the issue of scaling the discharges up to larger areas without compromising the plasma uniformity remains a major challenge. In this paper, we demonstrate a homogenous cold air plasma glow with a large cross-section generated by a direct current power supply. There is no risk of glow-to-arc transitions, and the plasma glow appears uniform regardless of the gap between the nozzle and the surface being processed. Detailed studies show that both the position of the quartz tube and the gas flow rate can be used to control the plasma properties. Further investigation indicates that the residual charges trapped on the inner surface of the quartz tube may be responsible for the generation of the air plasma plume with a large cross-section. The spatially resolved optical emission spectroscopy reveals that the air plasma plume is uniform as it propagates out of the nozzle. The remarkable improvement of the plasma uniformity is used to improve the bio-compatibility of a glass coverslip over a reasonably large area. This improvement is demonstrated by a much more uniform and effective attachment and proliferation of human embryonic kidney 293 (HEK 293) cells on the plasma-treated surface.

  12. Simulation of an Ar/NH{sub 3} low pressure magnetized direct current discharge

    SciTech Connect (OSTI)

    Li Zhi [School of Science, University of Science and Technology Liaoning, Anshan 114051 (China); School of Physics and Optoelectronic Engineering, Dalian University of Technology, Dalian 116024 (China); Zhao Zhen [School of Chemistry and Life Science, Anshan Normal University, Anshan 114007 (China); School of Chemical Engineering, University of Science and Technology Liaoning, Anshan 114051 (China); Li Xuehui [Physiccal Science and Technical College, Dalian University, Dalian 116622 (China)

    2013-01-15

    A two-dimensional fluid model has been used to investigate the properties of plasma in an Ar/NH{sub 3} low pressure magnetized direct current discharge. We compared the simulation results with the theoretical and experimental results of the other gas discharge in which the magnetic field is considered. Results that obtained using this method are in good agreement with literature. The simulation results show that the positive ammonia ion density follows the positive argon ion density. The Ar{sub 2}{sup +} density is slightly higher than the Ar{sup +} density at 100 mTorr. The largest ammonia ion is NH{sub 3}{sup +} ion, followed by NH{sub 2}{sup +}, NH{sub 4}{sup +}, and NH{sup +} ions. The contribution of NH{sup +} ions to the density of the positive ammonia ions is marginal. The influence of pressure on the plasma discharge has been studied by simulation, and the mechanisms have been discussed. The average plasma density increases as pressure increased. The plasma density appears to be more inhomogeneous than that at the lower pressure. The ratio of charge particles changed as pressure increased. The Ar{sup +} density is slightly higher than the Ar{sub 2}{sup +} density as the pressure increased. It makes NH{sub 4}{sup +} ratio increase as pressure increased. It shows that the electron temperature drops with rising pressure by numerical calculation.

  13. Direct Observation of Optically Injected Spin-Polarized Currents in Semiconductors

    E-Print Network [OSTI]

    Sipe,J. E.

    the developmentof spintronicsis the efficient and controlledinjection of carrier spin currents.We present here

  14. 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)

    2014-03-14

    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.

  15. Catalog of DC Appliances and Power Systems

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01

    direct-DC. The timing of EV charging relative to PV outputadded a hypothetical EV charging load. The EV load could bewith building loads. EV charging standards [26, 27

  16. 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 ...

  17. George Vachtsevanos, Panos Antsaklis, Kimon Valavanis, "Modeling and Control of Unmanned Aerial Vehicles Current Status and Future Directions," Chapter 9, Modeling and Control of Complex Systems, CRC

    E-Print Network [OSTI]

    Antsaklis, Panos

    of Unmanned Aerial Vehicles­ Current Status and Future Directions," Chapter 9, Modeling and Control of Complex of Unmanned Aerial Vehicles­ Current Status and Future Directions," Chapter 9, Modeling and Control of Complex of Unmanned Aerial Vehicles­ Current Status and Future Directions," Chapter 9, Modeling and Control of Complex

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

    SciTech Connect (OSTI)

    Matzen, Laura E.; Trumbo, Michael Christopher Stefan

    2014-10-01

    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.

  19. Direct current dielectric barrier assistant discharge to get homogeneous plasma in capacitive coupled discharge

    SciTech Connect (OSTI)

    Du, Yinchang; Li, Yangfang; Cao, Jinxiang; Liu, Yu; Wang, Jian; Zheng, Zhe

    2014-06-15

    In this paper, we propose a method to get more homogeneous plasma in the geometrically asymmetric capacitive coupled plasma (CCP) discharge. The dielectric barrier discharge (DBD) is used for the auxiliary discharge system to improve the homogeneity of the geometrically asymmetric CCP discharge. The single Langmuir probe measurement shows that the DBD can increase the electron density in the low density volume, where the DBD electrodes are mounted, when the pressure is higher than 5?Pa. By this manner, we are able to improve the homogeneity of the plasma production and increase the overall density in the target volume. At last, the finite element simulation results show that the DC bias, applied to the DBD electrodes, can increase the homogeneity of the electron density in the CCP discharge. The simulation results show a good agreement with the experiment results.

  20. Fast Compact Laser Shutter Using a Direct Current Motor and 3D Printing

    E-Print Network [OSTI]

    Zhang, Grace H; Kawasaki, Akio; Vuleti?, Vladan

    2015-01-01

    We present a mechanical laser shutter design that utilizes a DC electric motor to rotate a blade which blocks and unblocks a light beam. The blade and the main body of the shutter are modeled with computer aided design (CAD) and are produced by 3D printing. Rubber flaps are used to limit the blade's range of motion, reducing vibrations and preventing undesirable blade oscillations. At its nominal operating voltage, the shutter achieves a switching speed of (1.22 $\\pm$ 0.02) m/s with 1 ms activation delay and 10 $\\mu$s jitter in its timing performance. The shutter design is simple, easy to replicate, and highly reliable, showing no failure or degradation in performance over more than $10^8$ cycles.

  1. Direct imaging of enhanced current collection on grain boundaries of Cu(In,Ga)Se{sub 2} solar cells

    SciTech Connect (OSTI)

    Kim, JunHo; Kim, SeongYeon; Jiang, Chun-Sheng; Ramanathan, Kannan; Al-Jassim, Mowafak M.

    2014-02-10

    We report on direct imaging of current collection by performing conductive atomic force microscopy (C-AFM) measurement on a complete Cu(In,Ga)Se{sub 2} solar cell. The localized current was imaged by milling away the top conductive layer of the device by repeated C-AFM scans. The result exhibits enhanced photocurrent collection on grain boundaries (GBs) of CIGS films, consistent with the argument for electric-field-assisted carrier collection on the GBs.

  2. Current

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit theCovalent Bonding in ActinideRail betweenProtection andCurrent profile

  3. 2892 IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 29, NO. 6, NOVEMBER 2014 Optimal Power Flow in Direct Current Networks

    E-Print Network [OSTI]

    Wierman, Adam

    .g., photovoltaic panels, wind turbines, electric vehicles, electronic appliances, and fuel cells, are easier2892 IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 29, NO. 6, NOVEMBER 2014 Optimal Power Flow in Direct Current Networks Lingwen Gan and Steven H. Low, Fellow, IEEE Abstract--The optimal power flow (OPF

  4. 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

  5. DC source assemblies

    DOE Patents [OSTI]

    Campbell, Jeremy B; Newson, Steve

    2013-02-26

    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.

  6. The production mechanisms of OH radicals in a pulsed direct current plasma jet

    SciTech Connect (OSTI)

    Liu, X. Y.; Pei, X. K.; Lu, X. P.; Liu, D. W.; Ostrikov, K.

    2014-09-15

    The production mechanism of OH radicals in a pulsed DC plasma jet is studied by a two-dimensional (2-D) plasma jet model and a one-dimensional (1-D) discharge model. For the plasma jet in the open air, electron-impact dissociation of H{sub 2}O, electron neutralization of H{sub 2}O{sup +}, as well as dissociation of H{sub 2}O by O(1D) are found to be the main reactions to generate the OH species. The contribution of the dissociation of H{sub 2}O by electron is more than the others. The additions of N{sub 2}, O{sub 2}, air, and H{sub 2}O into the working gas increase the OH density outside the tube slightly, which is attributed to more electrons produced by Penning ionization. On the other hand, the additions of O{sub 2} and H{sub 2}O into the working gas increase the OH density inside the tube substantially, which is attributed to the increased O (1D) and H{sub 2}O concentration, respectively. The gas flow will transport high density OH out of the tube during pulse off period. It is also shown that the plasma chemistry and reactivity can be effectively controlled by the pulse numbers. These results are supported by the laser induced fluorescence measurements and are relevant to several applications of atmospheric-pressure plasmas in health care, medicine, and materials processing.

  7. 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 ...

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

    E-Print Network [OSTI]

    Tangirala, Umashanker

    1976-01-01

    if they are not deliberately maintained below toxic levels. This kind of air pollution problem is quite different from that of industrial emissions as it calls for the removal of mere traces of contaminant from large volumes of gas. For this purpose, conventional treatment... current corona discharge reactor, over a wide range of experimental conditions. The experi- mental variables were corona current, voltage, reactor radius ratio (Ri/R2), gas flow rate and temperature. Generally, more ozone was produced in the negative...

  9. Direct measurement of polysulfide shuttle current: A window into understanding the performance of lithium-sulfur cells

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

    Moy, Derek; Manivannan, A.; Narayanan, S. R.

    2014-11-04

    The shuttling of polysulfide ions between the electrodes in a lithium-sulfur battery is a major technical issue limiting the self-discharge and cycle life of this high-energy rechargeable battery. Although there have been attempts to suppress the shuttling process, there has not been a direct measurement of the rate of shuttling. We report here a simple and direct measurement of the rate of the shuttling (that we term “shuttle current”), applicable to the study of any type of lithium-sulfur cell. We demonstrate the effectiveness of this measurement technique using cells with and without lithium nitrate (a widely-used shuttle suppressor additive). Wemore »present a phenomenological analysis of the shuttling process and simulate the shuttle currents as a function of the state-of-charge of a cell. We also demonstrate how the rate of decay of the shuttle current can be used to predict the capacity fade in a lithium-sulfur cell due to the shuttle process. As a result, we expect that this new ability to directly measure shuttle currents will provide greater insight into the performance differences observed with various additives and electrode modifications that are aimed at suppressing the rate of shuttling of polysulfide ions and increasing the cycle life of lithium-sulfur cells.« less

  10. Direct measurement of polysulfide shuttle current: A window into understanding the performance of lithium-sulfur cells

    SciTech Connect (OSTI)

    Moy, Derek; Manivannan, A.; Narayanan, S. R.

    2014-11-04

    The shuttling of polysulfide ions between the electrodes in a lithium-sulfur battery is a major technical issue limiting the self-discharge and cycle life of this high-energy rechargeable battery. Although there have been attempts to suppress the shuttling process, there has not been a direct measurement of the rate of shuttling. We report here a simple and direct measurement of the rate of the shuttling (that we term “shuttle current”), applicable to the study of any type of lithium-sulfur cell. We demonstrate the effectiveness of this measurement technique using cells with and without lithium nitrate (a widely-used shuttle suppressor additive). We present a phenomenological analysis of the shuttling process and simulate the shuttle currents as a function of the state-of-charge of a cell. We also demonstrate how the rate of decay of the shuttle current can be used to predict the capacity fade in a lithium-sulfur cell due to the shuttle process. As a result, we expect that this new ability to directly measure shuttle currents will provide greater insight into the performance differences observed with various additives and electrode modifications that are aimed at suppressing the rate of shuttling of polysulfide ions and increasing the cycle life of lithium-sulfur cells.

  11. Direct measurement of polysulfide shuttle current: A window into understanding the performance of lithium-sulfur cells

    SciTech Connect (OSTI)

    Moy, Derek [Univ. of Southern California, Los Angeles, CA (United States). Loker Hydrocarbon Research Institute.; Manivannan, A. [National Energy Technology Lab. (NETL), Morgantown, WV (United States); Narayanan, S. R. [Univ. of Southern California, Los Angeles, CA (United States). Loker Hydrocarbon Research Institute.

    2014-11-01

    The shuttling of polysulfide ions between the electrodes in a lithium-sulfur battery is a major technical issue limiting the self-discharge and cycle life of this high-energy rechargeable battery. Although there have been attempts to suppress the shuttling process, there has not been a direct measurement of the rate of shuttling. We report here a simple and direct measurement of the rate of the shuttling (that we term “shuttle current”), applicable to the study of any type of lithium-sulfur cell. We demonstrate the effectiveness of this measurement technique using cells with and without lithium nitrate (a widely-used shuttle suppressor additive). We present a phenomenological analysis of the shuttling process and simulate the shuttle currents as a function of the state-of-charge of a cell. We also demonstrate how the rate of decay of the shuttle current can be used to predict the capacity fade in a lithium-sulfur cell due to the shuttle process. We expect that this new ability to directly measure shuttle currents will provide greater insight into the performance differences observed with various additives and electrode modifications that are aimed at suppressing the rate of shuttling of polysulfide ions and increasing the cycle life of lithium-sulfur cells.

  12. Measurement of positive direct current corona pulse in coaxial wire-cylinder gap

    SciTech Connect (OSTI)

    Yin, Han Zhang, Bo He, Jinliang Wang, Wenzhuo

    2014-03-15

    In this paper, a system is designed and developed to measure the positive corona current in coaxial wire-cylinder gaps. The characteristic parameters of corona current pulses, such as the amplitude, rise time, half-wave time, and repetition frequency, are statistically analyzed and a new set of empirical formulas are derived by numerical fitting. The influence of space charges on corona currents is tested by using three corona cages with different radii. A numerical method is used to solve a simplified ion-flow model to explain the influence of space charges. Based on the statistical results, a stochastic model is developed to simulate the corona pulse trains. And this model is verified by comparing the simulated frequency-domain responses with the measured ones.

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

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

    Maryland. merit08goodarzi.pdf More Documents & Publications WBG Converters and Chargers Vehicle Technologies Office Merit Review 2014: WBG Converters and Chargers Vehicle...

  14. 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:FinancingPetroleum Based Fuels Researchof Energy| DepartmentofEnergyiT HelpsBeyond Design10

  15. 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:FinancingPetroleum Based Fuels Researchof Energy| DepartmentofEnergyiT HelpsBeyond

  16. Building Scale DC Microgrids

    E-Print Network [OSTI]

    Marnay, Chris

    2013-01-01

    the likely emergence of fuel cells and required batteriesphotovoltaic cells, fuel cells, power quality, converters,DC) generation, e.g. fuel cells (FCs), from combustion

  17. Building Scale DC Microgrids

    E-Print Network [OSTI]

    Marnay, Chris

    2013-01-01

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

  18. Building Scale DC Microgrids

    E-Print Network [OSTI]

    Marnay, Chris

    2014-01-01

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

  19. Improved multi-directional eddy current inspection test apparatus for detecting flaws in metal articles

    DOE Patents [OSTI]

    Nance, Roy A. (McMurray, PA); Hartley, William H. (Pittsburgh, PA); Caffarel, Alfred J. (Pittsburgh, PA)

    1984-01-01

    Apparatus is described for detecting flaws in a tubular workpiece in a single scan. The coils of a dual coil bobbin eddy current inspection probe are wound at a 45.degree. angle to the transverse axis of the probe, one coil having an angular position about the axis about 90.degree. relative to the angular position of the other coil, and the angle of intersection of the planes containing the coils being about 60.degree..

  20. Direct-Current Resistivity At Beowawe Hot Springs Area (Garg, Et Al., 2007)

    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 QA:QA J-E-1 SECTIONRobertsdale, Alabama (UtilityInstrumentsArea (DOE GTP) JumpDillard Road SolarEngineeringDirect| Open

  1. Direct-Current Resistivity At Cove Fort Area (Warpinski, Et Al., 2004) |

    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 QA:QA J-E-1 SECTIONRobertsdale, Alabama (UtilityInstrumentsArea (DOE GTP) JumpDillard Road SolarEngineeringDirect|

  2. 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)

    2009-08-11

    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.

  3. Feasibility of gate-turnoff thyristors in a high-voltage direct-current transmission system: Final report

    SciTech Connect (OSTI)

    McMurray, W.

    1987-08-01

    This study to identify potentially attractive applications for gate-turnoff thyristor (GTO) converters in utility systems includes both high-voltage direct-current (HVDC) valves and static volt-ampere reactive (VAR) controllers. The work includes a broad review of basic principles and the power circuit arrangements that are judged to be most attractive. The major differences between ordinary thyristors and GTO converters are discussed, including alternative HVDC transmission systems and static VAR controllers that are possible with GTOs. Whereas a current-source type of converter is the obvious choice with ordinary thyristors, the use of GTOs allows either current-source or voltage-source converters to be considered. A computer-aided analysis of the basic 6-pulse GTO current-source converter system is presented, including general equations for steady-state operation and plotting calculated waveforms. An analysis of a GTO voltage-source converter is given in less detail. Due to incomplete performance data, unresolved critical problems such as protection, and the disadvantages of higher cost, complexity and losses, it is difficult to recommend a specific GTO converter system at this time. The major advantage that GTO converters can offer is rapid and smoothly continuous control of reactive power. Further development of GTO converters should be aimed towards an application where reactive power control is very important and not readily achievable by conventional methods. 12 refs., 47 figs.

  4. High voltage DC power supply

    DOE Patents [OSTI]

    Droege, Thomas F. (Batavia, IL)

    1989-01-01

    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.

  5. High voltage DC power supply

    DOE Patents [OSTI]

    Droege, T.F.

    1989-12-19

    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.

  6. A Superconducting transformer system for high current cable testing

    SciTech Connect (OSTI)

    Godeke, A.; Dietderich, D. R.; Joseph, J. M.; Lizarazo, J.; Prestemon, S. O.; Miller, G.; Weijers, H. W.

    2010-02-15

    This article describes the development of a direct-current (dc) superconducting transformer system for the high current test of superconducting cables. The transformer consists of a core-free 10 464 turn primary solenoid which is enclosed by a 6.5 turn secondary. The transformer is designed to deliver a 50 kA dc secondary current at a dc primary current of about 50 A. The secondary current is measured inductively using two toroidal-wound Rogowski coils. The Rogowski coil signal is digitally integrated, resulting in a voltage signal that is proportional to the secondary current. This voltage signal is used to control the secondary current using a feedback loop which automatically compensates for resistive losses in the splices to the superconducting cable samples that are connected to the secondary. The system has been commissioned up to 28 kA secondary current. The reproducibility in the secondary current measurement is better than 0.05% for the relevant current range up to 25 kA. The drift in the secondary current, which results from drift in the digital integrator, is estimated to be below 0.5 A/min. The system's performance is further demonstrated through a voltage-current measurement on a superconducting cable sample at 11 T background magnetic field. The superconducting transformer system enables fast, high resolution, economic, and safe tests of the critical current of superconducting cable samples.

  7. 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

  8. Metastability in a nano-bridge based hysteretic DC-SQUID embedded in superconducting microwave resonator

    E-Print Network [OSTI]

    Eran Segev; Oren Suchoi; Oleg Shtempluck; Fei Xue; Eyal Buks

    2010-07-29

    We study the metastable response of a highly hysteretic DC-SQUID made of a Niobium loop interrupted by two nano-bridges. We excite the SQUID with an alternating current and with direct magnetic flux, and find different stability zones forming diamond-like structures in the measured voltage across the SQUID. When such a SQUID is embedded in a transmission line resonator similar diamond structures are observed in the reflection pattern of the resonator. We have calculated the DC-SQUID stability diagram in the plane of the exciting control parameters, both analytically and numerically. In addition, we have obtained numerical simulations of the SQUID equations of motion, taking into account temperature variations and non-sinusoidal current-phase relation of the nano-bridges. Good agreement is found between experimental and theoretical results.

  9. 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit theCovalent BondingMeetingDifferences BetweenDirac Charge Dynamcs inDirect

  10. Directions

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit theCovalent BondingMeetingDifferencesPlatinum FuelEnergy InnovationDirections

  11. 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 Asryan, Levon V.

    2014-03-14

    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.

  12. Optimization of spin-torque switching using AC and DC pulses

    SciTech Connect (OSTI)

    Dunn, Tom [Department of Physics, University of Minnesota, Minneapolis, Minnesota 55455 (United States); Kamenev, Alex [Department of Physics, University of Minnesota, Minneapolis, Minnesota 55455 (United States); Fine Theoretical Physics Institute, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

    2014-06-21

    We explore spin-torque induced magnetic reversal in magnetic tunnel junctions using combined AC and DC spin-current pulses. We calculate the optimal pulse times and current strengths for both AC and DC pulses as well as the optimal AC signal frequency, needed to minimize the Joule heat lost during the switching process. The results of this optimization are compared against numeric simulations. Finally, we show how this optimization leads to different dynamic regimes, where switching is optimized by either a purely AC or DC spin-current, or a combination AC/DC spin-current, depending on the anisotropy energies and the spin-current polarization.

  13. Application of Direct Current Potential Drop for the J-integral vs. Crack Growth Resistance Curve Characterization

    SciTech Connect (OSTI)

    Chen, Xiang; Nanstad, Randy K; Sokolov, Mikhail A

    2014-01-01

    The direct current potential drop (DCPD) technique has been applied to derive the J-integral vs. crack growth resistance curve (J-R curve) for fracture toughness characterization of structural materials. The test matrix covered three materials including type 316LN stainless steels, Ni-based alloy 617, and one ferritic-martensitic steel, three specimen configurations including standard compact, single edge bending, and disk-shaped compact specimens, and temperatures ranging from 20 C to 650 C. When compared with baseline J-R curves derived from the ASTM normalization method, the original J-R curves from the DCPD technique yielded much smaller Jq values due to the influence of crack blunting, plastic deformation, etc. on potential drop. To counter these effects, a new procedure for adjusting DCPD J-R curves was proposed. After applying the new adjustment procedure, the average difference in Jq between the DCPD technique and the normalization method was only 5.2% and the difference in tearing modulus was 7.4%. The promising result demonstrates the applicability of the DCPD technique for the J-R curve characterization especially in extreme environments, such as elevated temperatures, where the conventional elastic unloading compliance method faces considerable challenges.

  14. Beam current sensor

    DOE Patents [OSTI]

    Kuchnir, M.; Mills, F.E.

    1984-09-28

    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.

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

    SciTech Connect (OSTI)

    Emoto, H.; Ando, Y.; Shinjo, T.; Shiraishi, M.; Shikoh, E.; Fuseya, Y.

    2014-05-07

    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.

  16. Magnetic properties of in-plane oriented barium hexaferrite thin films prepared by direct current magnetron sputtering

    SciTech Connect (OSTI)

    Zhang, Xiaozhi; Yue, Zhenxing Meng, Siqin; Yuan, Lixin

    2014-12-28

    In-plane c-axis oriented Ba-hexaferrite (BaM) thin films were prepared on a-plane (112{sup ¯}0) sapphire (Al{sub 2}O{sub 3}) substrates by DC magnetron sputtering followed by ex-situ annealing. The DC magnetron sputtering was demonstrated to have obvious advantages over the traditionally used RF magnetron sputtering in sputtering rate and operation simplicity. The sputtering power had a remarkable influence on the Ba/Fe ratio, the hematite secondary phase, and the grain morphology of the as-prepared BaM films. Under 80?W of sputtering power, in-plane c-axis highly oriented BaM films were obtained. These films had strong magnetic anisotropy with high hysteresis loop squareness (M{sub r}/M{sub s} of 0.96) along the in-plane easy axis and low M{sub r}/M{sub s} of 0.03 along the in-plane hard axis. X-ray diffraction patterns and pole figures revealed that the oriented BaM films grew via an epitaxy-like growth process with the crystallographic relationship BaM (101{sup ¯}0)//?-Fe{sub 2}O{sub 3}(112{sup ¯}0)//Al{sub 2}O{sub 3}(112{sup ¯}0)

  17. Dust acoustic waves in a direct current glow discharge C. Thompson, A. Barkan, N. D'Angelo, and R. L. Merlinoa)

    E-Print Network [OSTI]

    Merlino, Robert L.

    Dust acoustic waves in a direct current glow discharge C. Thompson, A. Barkan, N. D'Angelo, and R Received 25 February 1997; accepted 21 April 1997 An experimental investigation of dust acoustic DA waves electrostatically. The dust acoustic waves were produced by applying a modulation signal 5­40 Hz to the anode

  18. 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)

    2013-02-15

    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.

  19. 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

    2012-09-01

    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

  20. Improved DC Gun Insulator

    SciTech Connect (OSTI)

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

    2009-05-01

    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.

  1. Historical Material Analysis of DC745U Pressure Pads

    SciTech Connect (OSTI)

    Ortiz-Acosta, Denisse [Los Alamos National Laboratory

    2012-07-30

    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.

  2. Design Considerations for Very High Frequency dc-dc Converters

    E-Print Network [OSTI]

    Perreault, Dave

    the gating power while ensuring fast on- off transitions of the semiconductor switch. The rectifier of switching power converters operating at greatly increased switching frequencies. Greatly increasedDesign Considerations for Very High Frequency dc-dc Converters Juan M. Rivas, David Jackson, Olivia

  3. Correlations between 1/f noise and thermal treatment of Al-doped ZnO thin films deposited by direct current sputtering

    SciTech Connect (OSTI)

    Barhoumi, A. Guermazi, S.; Leroy, G.; Gest, J.; Carru, J. C.; Yang, L.; Boughzala, H.; Duponchel, B.

    2014-05-28

    Al-doped ZnO thin films (AZO) have been deposited on amorphous glass substrates by DC sputtering at different substrate temperatures T{sub s}. X-Ray diffraction results reveal that AZO thin films have a hexagonal wurtzite structure with (002) preferred orientation. (002) peaks indicate that the crystalline structure of the films is oriented with c-axis perpendicular to the substrate. Three-dimensional (3D) atomic force microscopy images of AZO thin films deposited on glass substrate at 200?°C, 300?°C, and 400?°C, respectively, shows the improvement of the crystallinity and the homogeneity of AZO thin films with T{sub s} which is in agreement with the noise measurements. The noise was characterized between 1?Hz and 100?kHz and we have obtained 1/f spectra. The noise is very sensitive to the crystal structure especially to the orientation of the crystallites which is perpendicular to the substrate and to the grain boundaries which generate a high current flow and a sharp increase in noise. Through time, R{sub sh} and [??]{sub eff} increase with the modification of the crystallinity of AZO thin films. Study of noise aging shows that the noise is more sensitive than resistivity for all AZO thin films.

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

    DOE Patents [OSTI]

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

    1995-05-23

    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.

  5. 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)

    1995-01-01

    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.

  6. Effect of Ti-Al cathode composition on plasma generation and plasma transport in direct current vacuum arc

    SciTech Connect (OSTI)

    Zhirkov, I. Petruhins, A.; Dahlqvist, M.; Ingason, A. S.; Rosen, J.; Eriksson, A. O.

    2014-03-28

    DC arc plasma from Ti, Al, and Ti{sub 1-x}Al{sub x} (x?=?0.16, 0.25, 0.50, and 0.70) compound cathodes was characterized with respect to plasma chemistry and charge-state-resolved ion energy. Scanning electron microscopy, X-ray diffraction, and Energy-dispersive X-ray spectroscopy of the deposited films and the cathode surfaces were used for exploring the correlation between cathode-, plasma-, and film composition. Experimental work was performed at a base pressure of 10{sup ?6}?Torr, to exclude plasma-gas interaction. The plasma ion composition showed a reduction of Al of approximately 5 at. % compared to the cathode composition, while deposited films were in accordance with the cathode stoichiometry. This may be explained by presence of neutrals in the plasma/vapour phase. The average ion charge states (Ti?=?2.2, Al?=?1.65) were consistent with reference data for elemental cathodes, and approximately independent on the cathode composition. On the contrary, the width of the ion energy distributions (IEDs) were drastically reduced when comparing the elemental Ti and Al cathodes with Ti{sub 0.5}Al{sub 0.5}, going from??150 and ?175?eV to ?100 and ?75?eV for Ti and Al ions, respectively. This may be explained by a reduction in electron temperature, commonly associated with the high energy tail of the IED. The average Ti and Al ion energies ranged between ?50 and ?61?eV, and ?30 and ?50?eV, respectively, for different cathode compositions. The attained energy trends were explained by the velocity rule for compound cathodes, which states that the most likely velocities of ions of different mass are equal. Hence, compared to elemental cathodes, the faster Al ions will be decelerated, and the slower Ti ions will be accelerated when originating from compound cathodes. The intensity of the macroparticle generation and thickness of the deposited films were also found to be dependent on the cathode composition. The presented results may be of importance for choice of cathodes for thin film depositions involving compound cathodes.

  7. Aalborg Universitet Power flow analysis for DC voltage droop controlled DC microgrids

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    Aalborg Universitet Power flow analysis for DC voltage droop controlled DC microgrids Li, Chendan). Power flow analysis for DC voltage droop controlled DC microgrids. In Proceedings of the 11th.aau.dk on: juli 07, 2015 #12;Power flow analysis for DC voltage droop controlled DC microgrids Chendan Li

  8. Fiber optic current monitor for high-voltage applications

    DOE Patents [OSTI]

    Renda, G.F.

    1992-04-21

    A current monitor which derives its power from the conductor being measured for bidirectionally measuring the magnitude of current (from DC to above 50 khz) flowing through a conductor across which a relatively high level DC voltage is applied, includes a pair of identical transmitter modules connected in opposite polarity to one another in series with the conductor being monitored, for producing from one module a first light signal having an intensity directly proportional to the magnitude of current flowing in one direction through the conductor during one period of time, and from the other module a second light signal having an intensity directly proportional to the magnitude of current flowing in the opposite direction through the conductor during another period of time, and a receiver located in a safe area remote from the high voltage area for receiving the first and second light signals, and converting the same to first and second voltage signals having levels indicative of the magnitude of current being measured at a given time. 6 figs.

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

    SciTech Connect (OSTI)

    Shepard, Kenneth L

    2013-03-31

    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.

  10. Collisional kinetics of non-uniform electric field, low-pressure, direct-current discharges in H$_{2}$

    E-Print Network [OSTI]

    Phelps, A V

    2010-01-01

    A model of the collisional kinetics of energetic hydrogen atoms, molecules, and ions in pure H$_2$ discharges is used to predict H$_\\alpha$ emission profiles and spatial distributions of emission from the cathode regions of low-pressure, weakly-ionized discharges for comparison with a wide variety of experiments. Positive and negative ion energy distributions are also predicted. The model developed for spatially uniform electric fields and current densities less than $10^{-3}$ A/m$^2$ is extended to non-uniform electric fields, current densities of $10^{3}$ A/m$^2$, and electric field to gas density ratios $E/N = 1.3$ MTd at 0.002 to 5 Torr pressure. (1 Td = $10^{-21}$ V m$^2$ and 1 Torr = 133 Pa) The observed far-wing Doppler broadening and spatial distribution of the H$_\\alpha$ emission is consistent with reactions among H$^+$, H$_2^+$, H$_3^+$, and H$^-H$ ions, fast H atoms, and fast H$_2$ molecules, and with reflection, excitation, and attachment to fast H atoms at surfaces. The H$_\\alpha$ excitation and ...

  11. DC Pro Software Tool Suite

    SciTech Connect (OSTI)

    2009-04-01

    This fact sheet describes how DOE's Data Center Energy Profiler (DC Pro) Software Tool Suite and other resources can help U.S. companies identify ways to improve the efficiency of their data centers.

  12. Interaction of DC-DC converters and submarine power cables in offshore wind farm DC networks 

    E-Print Network [OSTI]

    Wood, Thomas Benedict

    2014-06-30

    Offshore wind power is attracting increasing levels of research and investment. The use of HVDC transmission and the development of DC grids are topics with similar high levels of interest that go hand in hand with the ...

  13. A low-power magnetic-field-assisted plasma jet generated by dielectric-barrier discharge enhanced direct-current glow discharge at atmospheric pressure

    SciTech Connect (OSTI)

    Jiang, Weiman; Tang, Jie Wang, Yishan; Zhao, Wei; Duan, Yixiang; Research Center of Analytical Instrumentation, Sichuan University, Chengdu 610064

    2014-01-06

    A magnetic field is introduced to the dielectric-barrier discharge enhanced direct-current glow discharge for efficient plasma generation, with the discharge power of 2.7?W and total energy consumption reduced to 34% of the original. By spatially examining the emission spectra and plasma temperature, it is found that their peaks shift from edges to the center and the negative and anode glows merge into the positive column and disappear, accompanied by improvement of uniformity and chemical activity of the enlarged plasma. This lies in the enhancement of ionization in the curved and lengthened electron path and the dispersion of discharge domains.

  14. 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.; Radjenovi?, B.; Radmilovi?-Radjenovi?, M.

    2014-10-15

    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.

  15. Generating Isolated Outputs in a Multilevel Modular Capacitor Clamped DC-DC Converter

    E-Print Network [OSTI]

    Tolbert, Leon M.

    -dc converters based on inductive energy transfer method (IETM) such as buck, boost, and buck-boost converter967 Generating Isolated Outputs in a Multilevel Modular Capacitor Clamped DC-DC Converter (MMCCC clamped dc-dc converter. The multilevel modular capacitor clamped converter (MMCCC) has several key

  16. Scaling and laws of DC discharges as pointers for HiPIMS plasmas

    E-Print Network [OSTI]

    Maszl, Christian; von Keudell, Achim; Störi, Herbert

    2015-01-01

    Scaling or smiliarity laws of plasmas are of interest if lab size plasma sources are to be scaled for industrial processes. Ideally, the discharge parameters of the scaled plasmas are predictable and the fundamental physical processes are unaltered. Naturally, there are limitations and ranges of validity. Scaling laws for direct current glow discharges are well known. If a well diagnosed discharge is scaled, the field strength in the positive column, the gas amplification and the normal current density can easily be estimated. For non-stationary high power discharges like high power impulse magnetron sputtering (HiPIMS) plasmas, scaling is not as straight forward. Here, one deals with a non-stationary complex system with strong changes in plasma chemistry and symmetry breaks during the pulses. Because of the huge parameter space no good parameters are available to define these kind of discharges unambiguous at the moment. In this contribution we will discuss the scaling laws for DC glow discharges briefly and...

  17. Investigations of Ba{sub x}Sr{sub 1?x}TiO{sub 3} ceramics and powders prepared by direct current arc discharge technique

    SciTech Connect (OSTI)

    Li, Shuangbin; Wang, Xiaohan; Yao, Ying Jia, Yongzhong; Xie, Shaolei; Jing, Yan; Yuzyuk, Yu. I.

    2014-09-01

    Ba{sub x}Sr{sub 1?x}TiO{sub 3} ceramics with x ranging from 0 to 1 were prepared by direct current arc discharge technique and studied by means of x-ray diffraction (XRD) and Raman spectroscopy. The cubic-tetragonal ferroelectric phase transition in Ba{sub x}Sr{sub 1?x}TiO{sub 3} ceramics was found to occur at x???0.75. XRD investigation of as-grown BaTiO{sub 3} ceramics revealed co-existence of tetragonal and hexagonal modifications with a small amount of impurity phase BaTi{sub 4}O{sub 9}. No evidences of hexagonal phase were observed in Raman spectra of as-grown BaTiO{sub 3} ceramics, while Raman peaks related to hexagonal phase were clearly observed in the spectrum of fine-grain powders prepared from the same ceramics. A core-shell model for BaTiO{sub 3} ceramics prepared by direct current arc discharge technique is proposed. Absence of the hexagonal phase in any Ba{sub x}Sr{sub 1?x}TiO{sub 3} solid solution with x?

  18. 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

    2014-09-09

    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.

  19. Improved DC Gun and Insulator Assembly

    SciTech Connect (OSTI)

    Neubauer, Michael; Johnson, Rolland P

    2015-01-11

    Many user facilities such as synchrotron radiation light sources and free electron lasers rely on DC high voltage photoguns with internal field gradients as high as 10 to 15 MV/m. These high gradients often lead to field emission which poses serious problems for the photocathode used to generate the electron beam and the ceramic insulators used to bias the photocathode at high voltage. Ceramic insulators are difficult to manufacture, require long commissioning times, and have poor reliability, in part because energetic electrons bury themselves in the ceramic causing a buildup of charge and eventual puncture, and also because large diameter ceramics are difficult to braze reliably. The lifetimes of photo cathodes inside high current DC guns exhibiting field emission are limited to less than a hundred hours. Reducing the surface gradients on the metals reduces the field emission, which serves to maintain the required ultrahigh vacuum condition. A novel gun design with gradients around 5 MV/m and operating at 350 kV, a major improvement over existing designs, was proposed that allows for the in-situ replacement of photo cathodes in axially symmetric designs using inverted ceramics. In this project, the existing JLAB CEBAF asymmetric gun design with an inverted ceramic support was modeled and the beam dynamics characterized. An improved structure was designed that reduces the surface gradients and improves the beam optics. To minimize the surface gradients, a number of electrostatic gun designs were studied to determine the optimum configuration of the critical electrodes within the gun structure. Coating experiments were carried out to create a charge dissipative coating for cylindrical ceramics. The phase II proposal, which was not granted, included the design and fabrication of an axially symmetric DC Gun with an inverted ceramic that would operate with less than 5 MV/m at 350 kV and would be designed with an in-situ replaceable photo-cathode.

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

    E-Print Network [OSTI]

    Fowlkes, Catherine Kuhnle

    2007-01-01

    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 ...

  1. Catalog of DC Appliances and Power Systems

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01

    5V DC USB power from wall sockets. .. 52 viprovides 5V DC USB power from wall sockets. Reproduced withPower over Ethernet 51 Universal Serial Bus Wall

  2. Catalog of DC Appliances and Power Systems

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01

    main conclusions about off-grid markets for DC appliances,and power systems. Mature Off-Grid Markets for DC Appliancesapplications include off-grid residential, telecom, remote

  3. Catalog of DC Appliances and Power Systems

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01

    AEE Solar. 2010 Renewable Energy Design Guide and Catalog.2009, 2010, Interstate Renewable Energy Council. RetrievedDC) generated by on-site renewable energy systems in its DC

  4. A Superconducting transformer system for high current cable testing

    E-Print Network [OSTI]

    Godeke, A.

    2010-01-01

    A Superconducting Transformer System for High Current CableDC) superconducting transformer system for the high currentsuperconducting cables. The transformer consists of a core-

  5. Ecological benefits of dc power transmission

    SciTech Connect (OSTI)

    Kutuzova, N. B.

    2011-05-15

    The environmental effects of dc overhead transmission lines are examined. The major effects of ac and dc transmission lines are compared. Dc lines have advantages compared to ac lines in terms of electrical safety for people under the lines, biological effects, corona losses, and clearance width.

  6. Analysis and Optimization of Switched-Capacitor DC-DC Converters

    E-Print Network [OSTI]

    Sanders, Seth

    on conduction loss) of a ladder-type converter is found to be superior to that of a conventional boost converterAnalysis and Optimization of Switched-Capacitor DC-DC Converters Michael D. Seeman, Seth R. Sanders­ Analysis methods are developed that fully determine a switched-capacitor (SC) dc-dc converter's steady

  7. QER Public Meeting in Washington, DC: Enhancing Energy Infrastructure...

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

    Washington, DC: Enhancing Energy Infrastructure Resiliency and Addressing Vulnerabilities QER Public Meeting in Washington, DC: Enhancing Energy Infrastructure Resiliency and...

  8. DC Current in 4-N-Pentyl-40 -Cyanobiphenyl

    E-Print Network [OSTI]

    Reznikov, Yuri

    of Ukraine, Kyiv, Ukraine 2 Department of Physics, Case Western Reserve University, Cleveland, OH, USA of Physics, NAS of Ukraine, 46, Nauka Ave., Kyiv 03680, Ukraine. Tel.: þ38-044-5250820; Fax: þ38

  9. DESIGN & EXPERIMENTATION OF HIGH CURRENT DENSITY DC MAGNETOHYDRODYNAMIC (MHD) MICROPUMP

    E-Print Network [OSTI]

    Kassegne, Samuel Kinde

    effectively increases flow rate by deploying bubbles isolation and releasing mechanism that limit electrolyzed

  10. 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 RankADVANCED MANUFACTURING OFFICE INDUSTRIALU.S.Leadership on CleanUpListSummaryDepartment10 DOECost,

  11. Current Obsession: AC/DC | 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergy A plug-in electric vehicle (PEV)Day-June2012environment 3D31, 2015 |Energy,

  12. Computational study of flow dynamics from a dc arc plasma jet

    E-Print Network [OSTI]

    Trelles, Juan Pablo

    2013-01-01

    Plasma jets produced by direct-current (DC) non-transferred arc plasma torches, at the core of technologies ranging from spray coating to pyrolysis, present intricate dynamics due to the coupled interaction of fluid flow, thermal, and electromagnetic phenomena. The flow dynamics from an arc discharge plasma jet are investigated using time-dependent three-dimensional simulations encompassing the dynamics of the arc inside the torch, the evolution of the jet through the discharge environment, and the subsequent impingement of the jet over a flat substrate. The plasma is described by a chemical equilibrium and thermodynamic nonequilibrium (two-temperature) model. The numerical formulation of the physical model is based on a monolithic and fully-coupled treatment of the fluid and electromagnetic equations using a Variational Multiscale Finite Element Method. Simulation results uncover distinct aspects of the flow dynamics, including the jet forcing due to the movement of the electric arc, the prevalence of deviat...

  13. DC switching regulated power supply for driving an inductive load

    DOE Patents [OSTI]

    Dyer, G.R.

    1983-11-29

    A dc switching regulated power supply for driving an inductive load is provided. The regulator basic circuit is a bridge arrangement of diodes and transistors. First and second opposite legs of the bridge are formed by first and second parallel-connected transistor arrays, respectively, while the third and fourth legs of the bridge are formed by appropriately connected first and second parallel connected diode arrays, respectively. A dc power supply is connected to the input of the bridge and the output is connected to the load. A servo controller is provided to control the switching rate of the transistors to maintain a desired current to the load. The regulator may be operated in three stages or modes: (1) for current runup in the load, both first and second transistor switch arrays are turned on and current is supplied to the load through both transistor arrays. (2) When load current reaches the desired level, the first switch is turned off, and load current flywheels through the second switch array and the fourth leg diode array connecting the second switch array in series with the load. Current is maintained by alternating between modes 1 and 2 at a suitable duty cycle and switching rate set by the controller. (3) Rapid current rundown is accomplished by turning both switch arrays off, allowing load current to be dumped back into the source through the third and fourth diode arrays connecting the source in series opposition with the load to recover energy from the inductive load.

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

    SciTech Connect (OSTI)

    1999-05-01

    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.

  15. 45nm direct battery DC-DC converter for mobile applications

    E-Print Network [OSTI]

    Bandyopadhyay, Saurav

    2010-01-01

    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 ...

  16. Reactive sputtering of ?-ZrH{sub 2} thin films by high power impulse magnetron sputtering and direct current magnetron sputtering

    SciTech Connect (OSTI)

    Högberg, Hans Tengdelius, Lina; Eriksson, Fredrik; Broitman, Esteban; Lu, Jun; Jensen, Jens; Hultman, Lars; Samuelsson, Mattias

    2014-07-01

    Reactive sputtering by high power impulse magnetron sputtering (HiPIMS) and direct current magnetron sputtering (DCMS) of a Zr target in Ar/H{sub 2} plasmas was employed to deposit Zr-H films on Si(100) substrates, and with H content up to 61 at.?% and O contents typically below 0.2 at.?% as determined by elastic recoil detection analysis. X-ray photoelectron spectroscopy reveals a chemical shift of ?0.7?eV to higher binding energies for the Zr-H films compared to pure Zr films, consistent with a charge transfer from Zr to H in a zirconium hydride. X-ray diffraction shows that the films are single-phase ?-ZrH{sub 2} (CaF{sub 2} type structure) at H content >?55 at.?% and pole figure measurements give a 111 preferred orientation for these films. Scanning electron microscopy cross-section images show a glasslike microstructure for the HiPIMS films, while the DCMS films are columnar. Nanoindentation yield hardness values of 5.5–7 GPa for the ?-ZrH{sub 2} films that is slightly harder than the ?5 GPa determined for Zr films and with coefficients of friction in the range of 0.12–0.18 to compare with the range of 0.4–0.6 obtained for Zr films. Wear resistance testing show that phase-pure ?-ZrH{sub 2} films deposited by HiPIMS exhibit up to 50 times lower wear rate compared to those containing a secondary Zr phase. Four-point probe measurements give resistivity values in the range of ?100–120 ?? cm for the ?-ZrH{sub 2} films, which is slightly higher compared to Zr films with values in the range 70–80 ?? cm.

  17. 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.; Czigany, Zs.

    2012-07-01

    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.

  18. 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; Hu, Xu; Yang, Chunli

    2013-06-17

    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.

  19. Catalog of DC Appliances and Power Systems

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01

    mainly fluorescent and LED lighting and DC ceiling fans. TheFluorescent, CFL Lighting systems: LED Fluorescent and CFLlamps CFL lamps LED lamp CFL floodlight Lighting systems:

  20. Catalog of DC Appliances and Power Systems

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01

    similarly to an uninterruptible power supply. Lifetime:utility coupled with uninterruptible power requirements forloads serviced by DC uninterruptible power supplies in data

  1. SSL Demonstration: Parking Garage Lighting, Washington, DC

    SciTech Connect (OSTI)

    2013-06-01

    GATEWAY program report brief summarizing an SSL parking garage demonstration at the Dept. of Labor headquarters parking garage in Washington, DC.

  2. A Multiphase, Modular, Bidirectional, Triple-Voltage DC-DC Converter Power Systems

    SciTech Connect (OSTI)

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

    2008-01-01

    Electrical power systems in future hybrid and fuel cell vehicles may employ three voltage [14 V, 42 V, and high voltage (HV)] nets. These will be necessary to accommodate existing 14-V loads as well as efficiently handle new heavy loads at the 42-V net and a traction drive on the HV bus. A low-cost DC-DC converter was proposed for connecting the three voltage nets. It minimizes the number of switches and their associated gate driver components by using two half-bridges and a high-frequency transformer. Another salient feature is that the half bridge on the 42-V bus is also utilized to provide the 14-V bus by operating at duty ratios around an atypical value of 1/3. Moreover, it makes use of the parasitic capacitance of the switches and the transformer leakage inductance for soft switching. The use of half bridges makes the topology well suited for interleaved multiphase modular configurations as a means to increase the power level because the capacitor legs can be shared. This paper presents simulation and experimental results on an interleaved two-phase arrangement rated at 4.5 kW. Also discussed are the benefits of operating with an atypical duty ratio on the transformer and a preferred multiphase configuration to minimize capacitor ripple currents.

  3. 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 in photovoltaic energy processing applications is presented. The proposed approach acknowledges the influence through several case studies. Index Terms-- Markov reliability modeling, photovoltaic systems, power

  4. Design of a very high frequency resonant boost DC-DC converter

    E-Print Network [OSTI]

    Burkhart, Justin (Justin Michael)

    2010-01-01

    THIS thesis explores the development of a very high frequency DC-DC resonant boost converter. The topology examined features low parts count and fast transient response but suffers from higher device stresses compared to ...

  5. Design and evaluation of a very high frequency dc/dc converter

    E-Print Network [OSTI]

    Pilawa-Podgurski, Robert C. N

    2007-01-01

    This thesis presents a resonant boost topology suitable for very high frequency (VHF, 30-300 MHz) dc-dc power conversion. The proposed design is a fixed frequency, fixed duty ratio resonant converter featuring low device ...

  6. Design and characterization of a radio-frequency dc/dc power converter

    E-Print Network [OSTI]

    Jackson, David A. (David Alexander)

    2005-01-01

    The use of radio-frequency (RF) amplifier topologies in dc/dc power converters allows the operating frequency to be increased by more than two orders of magnitude over the frequency of conventional converters. This enables ...

  7. Radio frequency dc-dc converters : device characterization, topology evaluation, and design

    E-Print Network [OSTI]

    Leitermann, Olivia

    2008-01-01

    High frequency power conversion is attractive for the opportunities it affords for improved performance. Dc-dc converters operating at high frequencies use smaller-valued energy storage elements, which tend to be physically ...

  8. 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 ...

  9. The capacitively coupled converter (C³) for high power DC-DC conversion 

    E-Print Network [OSTI]

    Khan, Shahriar

    1992-01-01

    THE CAPACITIVELY COUPLED CONVERTER (C3) FOR HIGH POWER DC-DC CONVERSION A Thesis by SHAHRIAR KHAN Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER... OF SCIENCE May 1992 Major Subject: Electrical Engineering THE CAPACITIVELY COUPLED CONVERTER (Cs) FOR HIGH POWER DC-DC CONVERSION A Thesis by SHAHRIAR KHAN Approved as to style and content by: Mehrdad Ehsani (Chair of Committee) Prasad Enjeti...

  10. High Speed CMOS Output Stage for Integrated DC-DC Converters Wai Tung Ng*, Marian Changl

    E-Print Network [OSTI]

    Ng, Wai Tung

    to attain maximum channel width per unit area for low on-resistance. A typical MF layout and its equivalent DC/DC converters is characterized by power conversion efficiency, transient response, size and cost is introduced to enhance the switching speed and power conversion efficiency of low voltage integrated DC

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

    E-Print Network [OSTI]

    Gopinath, Rajesh

    2001-01-01

    (FEC)' organized by the Department of Energy and IEEE in August 2001. An efficient 3-terminal DC-DC push-pull topology was adopted to meet the performance and stringent cost constraints. A broad overview of the DC-AC inverter and its control is also...

  12. 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 conversion from AC to DC and inversion from DC to AC. We refer to the circuits which provide conversion from AC to DC as rectifiers and the circuits which provide conversion from DC to AC as inverters. The term

  13. Fault current limiter

    DOE Patents [OSTI]

    Darmann, Francis Anthony

    2013-10-08

    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.

  14. DC-based magnetic field controller

    DOE Patents [OSTI]

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

    1994-01-01

    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.

  15. Data:12a45141-7972-4ec8-a2dc-37fedc8133d3 | Open Energy Information

    Open Energy Info (EERE)

    ec8-a2dc-37fedc8133d3 No revision has been approved for this page. It is currently under review by our subject matter experts. Jump to: navigation, search Loading... 1. Basic...

  16. Data:7a23ab07-5468-48dc-947a-679327ca61e0 | Open Energy Information

    Open Energy Info (EERE)

    dc-947a-679327ca61e0 No revision has been approved for this page. It is currently under review by our subject matter experts. Jump to: navigation, search Loading... 1. Basic...

  17. 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.

    2002-08-01

    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...

  18. Aternating current photovoltaic building block

    DOE Patents [OSTI]

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

    2004-06-15

    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.

  19. PLEASE NOTE: Current rent specials are only valid with direct referrals from NU-FSOM housing. Other buildings throughout Chicago may also offer special rental incentives, so feel free to research other housing options on your own.

    E-Print Network [OSTI]

    Chisholm, Rex L.

    PLEASE NOTE: Current rent specials are only valid with direct referrals from NU-FSOM housing. Other housing options on your own. THURSDAY, MARCH 26TH ­ SATURDAY, MARCH 28TH Most buildings do not require R. The specific open house hours for each building and their apartment floor plans are listed below: BUILDING

  20. Alcohol Outlets and Violent Crime in Washington D.C.

    E-Print Network [OSTI]

    Franklin, F. Abron; LaVeist, Thomas A.; Webster, Daniel W.; Pan, William K.

    2010-01-01

    of Violence and Disorder. Washington, D.C. : The Urbanand Violent Crime in Washington D.C. F. Abron Franklin II,Involvement in Crime. Washington, D.C. : U.S. Department of

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

    DOE Patents [OSTI]

    Su, Gui-Jia [Knoxville, TN

    2005-11-29

    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.

  2. DC switching regulated power supply for driving an inductive load

    DOE Patents [OSTI]

    Dyer, George R. (Norris, TN)

    1986-01-01

    A power supply for driving an inductive load current from a dc power supply hrough a regulator circuit including a bridge arrangement of diodes and switching transistors controlled by a servo controller which regulates switching in response to the load current to maintain a selected load current. First and second opposite legs of the bridge are formed by first and second parallel-connected transistor arrays, respectively, while the third and fourth legs of the bridge are formed by appropriately connected first and second parallel connected diode arrays, respectively. The regulator may be operated in three "stages" or modes: (1) For current runup in the load, both first and second transistor switch arrays are turned "on" and current is supplied to the load through both transistor arrays. (2) When load current reaches the desired level, the first switch is turned "off", and load current "flywheels" through the second switch array and the fourth leg diode array connecting the second switch array in series with the load. Current is maintained by alternating between modes 1 and 2 at a suitable duty cycle and switching rate set by the controller. (3) Rapid current rundown is accomplished by turning both switch arrays "off", allowing load current to be dumped back into the source through the third and fourth diode arrays connecting the source in series opposition with the load to recover energy from the inductive load. The three operating states are controlled automatically by the controller.

  3. EA-351 DC Energy Dakota, LLC | Department of Energy

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

    Dakota, LLC Order authorizing DC Energy Dakota, LLC to export electric energy to Canada EA-351 DC Energy Dakota, LLC More Documents & Publications Application to Export...

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

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

    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 Systems...

  5. Report Now Available: DC Microgrids Scoping Study--Estimate of...

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

    Report Now Available: DC Microgrids Scoping Study--Estimate of Technical and Economic Benefits (March 2015) Report Now Available: DC Microgrids Scoping Study--Estimate of Technical...

  6. Energy Department Completes Cool Roof Installation on DC Headquarters...

    Energy Savers [EERE]

    Energy Department Completes Cool Roof Installation on DC Headquarters Building to Save Money by Saving Energy Energy Department Completes Cool Roof Installation on DC Headquarters...

  7. AVTA: Battery Testing - DC Fast Charging's Effects on PEV Batteries...

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

    Battery Testing - DC Fast Charging's Effects on PEV Batteries AVTA: Battery Testing - DC Fast Charging's Effects on PEV Batteries The Vehicle Technologies Office's Advanced Vehicle...

  8. AVTA: Hasdec DC Fast Charging Testing Results | Department of...

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

    Hasdec DC Fast Charging Testing Results AVTA: Hasdec DC Fast Charging Testing Results The Vehicle Technologies Office's Advanced Vehicle Testing Activity carries out testing on a...

  9. NOISE AND OPTIMIZATION OF THE dc SQUID

    E-Print Network [OSTI]

    Tesche, Claudia Denke

    2011-01-01

    unpublished). A. Van der Ziel, Noise (Prentice-Hall, Inc. ,MAY 29 19ft LBL-8510 MASTER NOISE AND OPTIMIZATION OF THE deW-7405-ENG-48 LBL-8510 NOISE AND OPTIMIZATION OF THE dc

  10. Catalog of DC Appliances and Power Systems

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01

    DC/AC-Hybrid) LED AC LED Power (W) Figure 8. Efficacywith the same power consumption. For LEDs, the improvementLED light-emitting diode viii lumen a measure of the power

  11. DC High School Science Bowl Regionals

    Broader source: Energy.gov [DOE]

    This event is the Washington, D.C. High School Regional competition for the US National Science Bowl. The regional competition is run by the Office of Economic Impact and Diversity, and the...

  12. Catalog of DC Appliances and Power Systems

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01

    Ovens Electric Heat Pumps Geothermal Heat Pumps Solar WaterOvens Appliance DC-internal product power (Watts) Personal Computers and Related Equipment Rechargeable Electronics Refrigerators Room Air Conditioners Security Systems Solar

  13. Catalog of DC Appliances and Power Systems

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01

    produce a DC-compatible dishwasher that uses 51% less energyCooking Equipments Dishwashers Lighting Electric Other Waterby end-Use ( TWh) Dishwashers DVDs/VCRs DVDs/VCRs Freezers

  14. Salmonella inhibit T cell proliferation by a direct, contact-dependent immunosuppressive effect

    E-Print Network [OSTI]

    Starnbach, Michael

    Salmonella inhibit T cell proliferation by a direct, contact-dependent immunosuppressive effect or activate B and T cells. In this article, we report that DC, when cocultured with Salmonella, fail to Salmonella-infected DC is not simply due to Salmonella- induced programmed DC death or interference with up

  15. Current measurement apparatus

    DOE Patents [OSTI]

    Umans, Stephen D. (Belmont, MA)

    2008-11-11

    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.

  16. Contrib. Plasma Phys. 47, No. 1-2, 9 18 (2007) / DOI 10.1002/ctpp.200710003 Simulation of Direct-Current Microdischarges for Application in

    E-Print Network [OSTI]

    Raja, Laxminarayan L.

    2007-01-01

    -Current Microdischarges for Application in Electro-Thermal Class of Small Satellite Propulsion Devices P. S. Kothnur and L. L. Raja Department of Aerospace Engineering and Engineering Mechanics, The University of Texas 2007 Key words Microdischarge, fluid model, glow discharge, neutral gas heating, plasma

  17. Auxiliary quasi-resonant dc tank electrical power converter

    DOE Patents [OSTI]

    Peng, Fang Z.

    2006-10-24

    An auxiliary quasi-resonant dc tank (AQRDCT) power converter with fast current charging, voltage balancing (or charging), and voltage clamping circuits is provided for achieving soft-switched power conversion. The present invention is an improvement of the invention taught in U.S. Pat. No. 6,111,770, herein incorporated by reference. The present invention provides faster current charging to the resonant inductor, thus minimizing delay time of the pulse width modulation (PWM) due to the soft-switching process. The new AQRDCT converter includes three tank capacitors or power supplies to achieve the faster current charging and minimize the soft-switching time delay. The new AQRDCT converter further includes a voltage balancing circuit to charge and discharge the three tank capacitors so that additional isolated power supplies from the utility line are not needed. A voltage clamping circuit is also included for clamping voltage surge due to the reverse recovery of diodes.

  18. American Institute of Aeronautics and Astronautics Active System Identification of a DC-DC Converter Using

    E-Print Network [OSTI]

    American Institute of Aeronautics and Astronautics 1 Active System Identification of a DC and Computer Engineering, UCB 425. #12;American Institute of Aeronautics and Astronautics 2 analysis10

  19. Improved DC Gun Insulator Assembly

    SciTech Connect (OSTI)

    Sah, R.; Dudas, A.; Neubauer, M. L.; Poelker, M.; Surles-Law, K. E.L.

    2010-05-23

    Many user fa­cil­i­ties such as syn­chrotron ra­di­a­tion 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 often ex­hib­it poor re­li­a­bil­i­ty. Two tech­ni­cal ap­proach­es to solv­ing this prob­lem will be in­ves­ti­gat­ed. First­ly, in­vert­ed ce­ram­ics offer so­lu­tions for re­duced gra­di­ents be­tween the elec­trodes and ground. An in­vert­ed de­sign will be pre­sent­ed for 350 kV, with max­i­mum gra­di­ents in the range of 5-10 MV/m. Sec­ond­ly, novel ce­ram­ic man­u­fac­tur­ing pro­cess­es will be stud­ied, in order to pro­tect triple junc­tion lo­ca­tions from emis­sion, by ap­ply­ing a coat­ing with a bulk re­sis­tiv­i­ty. The pro­cess­es for cre­at­ing this coat­ing will be op­ti­mized to pro­vide pro­tec­tion as well as be used to coat a ce­ram­ic with an ap­pro­pri­ate gra­di­ent in bulk re­sis­tiv­i­ty from the vac­u­um side to the air side of an HV stand­off ce­ram­ic cylin­der. Ex­am­ple in­su­la­tor de­signs are being com­put­er mod­elled, and in­su­la­tor sam­ples are being man­u­fac­tured and test­ed

  20. Performance Study of K2CsSb Photocathode inside a DC High Voltage Gun

    SciTech Connect (OSTI)

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

    2011-03-01

    In the past decade, there has been considerable interest in the generation of tens of mA average current in a photoinjector. Until recently, GaAs:Cs cathodes and K2CsSb cathodes have been tested successfully in DC and RF injectors respectively for this application. Our goal is to test the GaAs:Cs in RF injector and the K2CsSb cathode in the DC gun in order to widen our choices. Since the multialkali cathode is a compound with uniform stochiometry over its entire thickness, we anticipate that the life time issues seen in GaAs:Cs due surface damage by ion bombardment would be minimized with this material. Hence successful operation of the K2CsSb cathode in DC gun could lead to a relatively robust electron source capable of delivering ampere level currents. In order to test the performance of K2CsSb cathode in a DC gun, we have designed and built a load lock system that would allow the fabrication of the cathode at BNL and its testing at JLab. In this paper, we will present the design of the load-lock system, cathode fabrication, and the cathode performance in the preparation chamber and in the DC gun.

  1. Performance Study of K2CsSb Photocathode Inside a DC High Voltage Gun

    SciTech Connect (OSTI)

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

    2011-09-01

    In the past decade, there has been considerable interest in the generation of tens of mA average current in a photoinjector. Until recently, GaAs:Cs cathodes and K{sub 2}CsSb cathodes have been tested successfully in DC and RF injectors respectively for this application. Our goal is to test the K{sub 2}CsSb photocathode inside a DC gun. Since the multialkali cathode is a compound with constant characteristics over its entire thickness, we anticipate that the lifetime issues seen in GaAs:Cs due to surface damage by ion bombardment would be minimized. Hence successful operation of the K{sub 2}CsSb cathode in a DC gun could lead to a relatively robust electron source capable of delivering ampere level currents. In order to test the performance of a K{sub 2}CsSb cathode in a DC gun, we have designed and built a load lock system that allows the fabrication of the cathode at Brookhaven National Lab (BNL) and its testing at Jefferson Lab (JLab). In this paper, we will present the performance of the K{sub 2}CsSb photocathode in the preparation chamber and in the DC gun.

  2. A DC-DC Converter-Based PEM Fuel Cell System Emulator

    E-Print Network [OSTI]

    Boyer, Edmond

    A DC-DC Converter-Based PEM Fuel Cell System Emulator Daoud Rezzak, Farid Khoucha, Mohamed Benbouzid, Abdelaziz Kheloui and Abdeslam Mamoune Abstract--The Proton Exchange Membrane Fuel Cell (PEMFC power supplies. Fuel cell systems are characterized by high costs and complex auxiliary devices

  3. DC's Marble ceiling : urban height and its regulation in Washington, DC

    E-Print Network [OSTI]

    Trueblood, Andrew Tyson

    2009-01-01

    Washington, DC has a unique urban form that is the result of a century-old law. Through the narrow lens of DC's height limit, I survey a range of topics related to urban height, starting with a review of its history of ...

  4. Method to Improve Total Dose Radiation Hardness in a CMOS dc-dc Boost

    E-Print Network [OSTI]

    Wilamowski, Bogdan Maciej

    Method to Improve Total Dose Radiation Hardness in a CMOS dc-dc Boost Converter Huadian Pan in a wide range of radiation environment, with increasing total dose radiation, The efticieney also greatly for low-power applications (1],[2]. It is known that radiation has many effects on MOSFETs

  5. Development of a 55 kW 3X DC-DC Converter for HEV Systems

    E-Print Network [OSTI]

    Tolbert, Leon M.

    efficiency provide the great potential for the very high temperature operation. The circuit parameter design converter and a traction motor to drive the vehicle. In most commercial HEV systems, the power converter, 37996 Abstract--The design of a 55 kW 3X dc-dc converter is presented for hybrid electric vehicle (HEV

  6. Time domain design of digital compensators for PWM DC-DC converters

    E-Print Network [OSTI]

    transformation and discretization. Digital PID controllers for a Buck and Boost type converters were implemented (via the various transformation algorithms), a digital compensator operates, in reality, in the sampledTime domain design of digital compensators for PWM DC-DC converters Mor Mordechai Peretz and Sam

  7. 5 kW Multilevel DC-DC Converter for Hybrid Electric and Fuel Cell Automotive

    E-Print Network [OSTI]

    Tolbert, Leon M.

    5 kW Multilevel DC-DC Converter for Hybrid Electric and Fuel Cell Automotive Applications Faisal H) for future hybrid electric vehicle and fuel cell automotive applications will be presented in this paper will impact if the 42V/14V dual bus system will be a successful and cost effective solution for future

  8. Aalborg Universitet Optimization with System Damping Restoration for Droop Controlled DC-DC

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    --The parallel operation of dc-dc converters is widely used in distribution systems and uninterruptable power supply systems. Droop control along with virtual resistance (VR) is considered a simple and reliable method for achieving wireless power sharing among converters. In order to enhance the efficiency

  9. DC WRRC Report No. 44 THE D.C. WATER RESOURCES RESEARCH CENTER

    E-Print Network [OSTI]

    District of Columbia, University of the

    . The agreements will reduce the possibility of water shortages during low flows or pollution crisis and insure for new expanded treatment facilities. Finally, the recently completed Rock Creek water shed study has#12;DC WRRC Report No. 44 THE D.C. WATER RESOURCES RESEARCH CENTER THE UNIVERSITY OF THE DISTRICT

  10. 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

  11. Homopolar dc motor and trapped flux brushless dc motor using high temperature superconductor materials

    SciTech Connect (OSTI)

    Crapo, A.D.; Lloyd, J.D. (Emerson Electric Co., St. Louis, MO (US))

    1991-03-01

    This paper reports on two motors designed and built for use with high temperature superconductor (HTSC) materials. They are a homopolar DC motor that will use HTSC field windings and a brushless DC motor that will use bulk HTSC material to trap flux in steel rotor poles. The HTSC field windings of the homopolar DC motor are designed to operate at 1000 Amperes/cm{sup 2} in a 0.010 Tesla (100 Gauss) field. In order to maximize torque in the homopolar DC motor, an iron magnetic circuit with small air gaps gives maximum flux for minimum Ampere turns in the field. A copper field winding version of the homopolar DC motor has been tested while the authors wait for 575 Ampere turn HTSC coils.

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

    SciTech Connect (OSTI)

    Saive, Rebecca Kowalsky, Wolfgang; Institut für Hochfrequenztechnik, TU Braunschweig, 38106 Braunschweig; Kirchhoff-Institute for Physics, Heidelberg University, 69120 Heidelberg ; Mueller, Christian; Kirchhoff-Institute for Physics, Heidelberg University, 69120 Heidelberg ; Schinke, Janusz; Lovrincic, Robert; Institut für Hochfrequenztechnik, TU Braunschweig, 38106 Braunschweig

    2013-12-09

    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.

  13. Thermal cum DC Camouflage in Duet with Undecorated Natural Materials

    E-Print Network [OSTI]

    Yang, Tian-Zhi; Gao, Dongliang; Wu, Linzhi; Li, Baowen; Thong, John T L; Qiu, Cheng-Wei

    2015-01-01

    To manipulate various types of physical signals in one single device has long captivated the attention of scientists and engineers. This however is very challenging, if not impossible, even for emerging metamaterials. Up to date, many artificial materials have been proposed, theoretically and (or) experimentally, for manipulating various waves/signals on a one-function-one-device basis. In this work, for the very first time, we employ undecorated natural materials to experimentally demonstrate a simultaneous camouflage for thermal current and electric dc current on the same device. It demonstrates how ingenuity can overcome the limitations of natural material systems without the need for complex decoration to impart inhomogeneous and (or) anisotropic properties, which was previously considered impossible to accomplish except by using metamaterials.

  14. Bifurcation in Parallel-Connected Buck Converters under Current-Mode Control

    E-Print Network [OSTI]

    Tse, Chi K. "Michael"

    converter, boost converter and buck-boost converter) have been thoroughly studied in the past decade [1], [2Bifurcation in Parallel-Connected Buck Converters under Current-Mode Control H. H. C. Iu School a system of parallel-connected dc/dc buck converters under current-mode control. The effects of variations

  15. Ionization tube simmer current circuit

    DOE Patents [OSTI]

    Steinkraus, R.F. Jr.

    1994-12-13

    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.

  16. Ionization tube simmer current circuit

    DOE Patents [OSTI]

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

    1994-01-01

    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.

  17. Data:E27214d6-18ee-410f-87b6-ecf189dc6f07 | Open Energy Information

    Open Energy Info (EERE)

    ecf189dc6f07 No revision has been approved for this page. It is currently under review by our subject matter experts. Jump to: navigation, search Loading... 1. Basic Information 2....

  18. Data:6941e69c-3b58-4100-9f8a-95b61dc551f9 | Open Energy Information

    Open Energy Info (EERE)

    dc551f9 No revision has been approved for this page. It is currently under review by our subject matter experts. Jump to: navigation, search Loading... 1. Basic Information 2....

  19. An Exploration of the Perceptions and Utilizations of Networking Systems in Washington, D.C.

    E-Print Network [OSTI]

    Lindsey, Robynne

    2013-01-01

    Personal Interview. Washington, D.C. , July 25, 2013.Personal Interview. Washington, D.C. , August 12, 2013.Personal Interview. Washington, D.C. , July 17, 2013. 12

  20. Computational study of flow dynamics from a dc arc plasma jet

    E-Print Network [OSTI]

    Juan Pablo Trelles

    2013-03-15

    Plasma jets produced by direct-current (DC) non-transferred arc plasma torches, at the core of technologies ranging from spray coating to pyrolysis, present intricate dynamics due to the coupled interaction of fluid flow, thermal, and electromagnetic phenomena. The flow dynamics from an arc discharge plasma jet are investigated using time-dependent three-dimensional simulations encompassing the dynamics of the arc inside the torch, the evolution of the jet through the discharge environment, and the subsequent impingement of the jet over a flat substrate. The plasma is described by a chemical equilibrium and thermodynamic nonequilibrium (two-temperature) model. The numerical formulation of the physical model is based on a monolithic and fully-coupled treatment of the fluid and electromagnetic equations using a Variational Multiscale Finite Element Method. Simulation results uncover distinct aspects of the flow dynamics, including the jet forcing due to the movement of the electric arc, the prevalence of deviations between heavy-species and electron temperatures in the plasma fringes, the development of shear flow instabilities around the jet, the occurrence of localized regions with high electric fields far from the arc, and the formation and evolution of coherent flow structures.

  1. FEDERAL COMMUNICATIONS COMMISSION Washington, DC 20554

    E-Print Network [OSTI]

    Bove Jr., V. Michael

    FCC 96­207 Before the FEDERAL COMMUNICATIONS COMMISSION Washington, DC 20554 In the Matter of a mechanism for a bit stream layer transmission standard (into which, e.g., MPEG­2 could fit) 3) The FCC: number of hours per day of digital television transmission, minimal Quality of Service specifications

  2. Halbach array DC motor/generator

    DOE Patents [OSTI]

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

    1998-01-01

    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.

  3. Halbach array DC motor/generator

    DOE Patents [OSTI]

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

    1998-01-06

    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.

  4. Geothermal Energy: Current abstracts

    SciTech Connect (OSTI)

    Ringe, A.C. (ed.)

    1988-02-01

    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)

  5. SUBCONTRACT REPORT: DC-DC Converter for Fuel Cell and Hybrid Vehicles

    SciTech Connect (OSTI)

    Marlino, Laura D; Zhu, Lizhi

    2007-07-01

    The goal of this project is to develop and fabricate a 5kW dc-dc converter with a baseline 14V output capability for fuel cell and hybrid vehicles. The major objectives for this dc-dc converter technology are to meet: Higher efficiency (92%); High coolant temperature,e capability (105 C); High reliability (15 Years/150,000miles); Smaller volume (5L); Lower weight (6kg); and Lower cost ($75/kW). The key technical challenge for these converters is the 105 C coolant temperatures. The power switches and magnetics must be designed to sustain these operating temperatures reliably, without a large cost/mass/volume penalty.

  6. D.C. Water Resources Research Center Annual Technical Report

    E-Print Network [OSTI]

    - DC Water and Sewer Authority (WASA) The Institutes received favorable responses from and met with the following new Advisory Board members: 1- Mr. Richard Gianni, Water Quality Manager, DC Water and Sewer

  7. Decoherence and dephasing errors caused by the dc Stark effect...

    Office of Scientific and Technical Information (OSTI)

    Decoherence and dephasing errors caused by the dc Stark effect in rapid ion transport Citation Details In-Document Search Title: Decoherence and dephasing errors caused by the dc...

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

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

    applications where the end-use loads are natively DC, e.g., computers, solid-state lighting, and building networks. These early DC applications may provide higher efficiency,...

  9. Persons Who Received the DC PSC's Emergency Petition and Complaint...

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

    Persons Who Received the DC PSC's Emergency Petition and Complaint via E-mail on August 24, 2005 Persons Who Received the DC PSC's Emergency Petition and Complaint via E-mail on...

  10. Aalborg Universitet Hierarchical Control for Multiple DC-Microgrids Clusters

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    , and energy storages (e.g., secondary battery and super capacitor) [7]­[15]. Normally, dc MGs are proposed

  11. 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?

  12. Exploring the Raft River geothermal area, Idaho, with the dc...

    Open Energy Info (EERE)

    the dc resistivity method (Abstract) Abstract GEOTHERMAL ENERGY; GEOTHERMAL FIELDS; ELECTRICAL SURVEYS; IDAHO; GEOTHERMAL EXPLORATION; RAFT RIVER VALLEY; ELECTRIC CONDUCTIVITY;...

  13. Urbanisation de DC ANF Datacentres 2 Octobre 2014

    E-Print Network [OSTI]

    van Tiggelen, Bart

    Urbanisation de DC ANF Datacentres ­ 2 Octobre 2014 Cargese Urbanisation des Datacentres Romaric David david@unistra.fr Univerité de Strasbourg 2 Octobre 2014 #12;2 Urbanisation de DC ANF Datacentres constructeurs Conclusion #12;3 Urbanisation de DC ANF Datacentres ­ 2 Octobre 2014 Cargese Introduction Centre

  14. D.C. Water Resources Research Center Annual Technical Report

    E-Print Network [OSTI]

    D.C. Water Resources Research Center Annual Technical Report FY 2007 D.C. Water Resources Research of the District of Columbia (DC) Water Resources Research Institute (the Institute) for the period of March 1 relevant water resources research results and transfer information to assist policy makers and residents

  15. 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). Hierarchical Control for Multiple DC Microgrids Clusters. I E E E Transactions on Energy Conversion, 29(4), 922. Dragicevic, J. C. Vasquez, and J. M. Guerrero, "Hierarchical Control for Multiple DC-Microgrids Clusters

  16. RF MEMS DC CONTACT SWTCHES FOR RECONFIGURABLE Presented to the

    E-Print Network [OSTI]

    Kassegne, Samuel Kinde

    RF MEMS DC CONTACT SWTCHES FOR RECONFIGURABLE ANTENNAS _______________ A Thesis Presented STATE UNIVERSITY The Undersigned Faculty Committee Approves the Thesis of Lei Zhou: RF DC Contact MEMS rock and water, water, through persistence, eventually wins. #12;vi ABSTRACT OF THE THESIS RF MEMS DC

  17. Q&A: Kristen Psaki of WeatherizeDC

    Broader source: Energy.gov [DOE]

    Roughly 20 percent of carbon emissions come from inefficient homes. The DC Project says it has found a way to mitigate emissions and create jobs, a winning combination. WeatherizeDC is the non-profit’s effort to use a community engagement model to help DC residents find green jobs and live a more energy efficient lifestyle.

  18. Energy Challenge Two: The WeatherizeDC Campaign

    Broader source: Energy.gov [DOE]

    WeatherizeDC is a campaign of The DC Project, a nonprofit based in Washington, D.C., founded by former leaders of the Obama for America campaign around a mission to advance economic and environmental justice by creating clean energy career opportunities for people who need them most.

  19. 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

    2010-03-23

    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.

  20. Low Power DC-DC Converters and a Low Quiescent Power High PSRR Class-D Audio Amplifier 

    E-Print Network [OSTI]

    Torres, Joselyn

    2013-12-03

    High-performance DC-DC voltage converters and high-efficient class-D audio amplifiers are required to extend battery life and reduce cost in portable electronics. This dissertation focuses on new system architectures and design techniques...

  1. 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...

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

    DOE Patents [OSTI]

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

    2014-10-14

    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.

  3. Possible temperature control DC switch effect between two superconductors

    E-Print Network [OSTI]

    Tian De Cao

    2011-08-11

    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.

  4. Effect of DC voltage pulses on memristor behavior.

    SciTech Connect (OSTI)

    Evans, Brian R.

    2013-10-01

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

  5. Computer-Aided Optimization of dc/dc Converters for Automotive Applications Timothy C. Neugebauer David J. Perreault

    E-Print Network [OSTI]

    Perreault, Dave

    Computer-Aided Optimization of dc/dc Converters for Automotive Applications Timothy C. Neugebauer/dc converters, with a focus on converters for dual-voltage automotive electrical systems. A new CAD optimization is the next evolutionary step for automotive electrical systems. High-power loads will be moved to a new high

  6. Abstract Many control schemes for dc-dc converters begin with the assertion that inductor currents are "fast" states and

    E-Print Network [OSTI]

    Kimball, Jonathan W.

    work, singular perturbation theory is applied to boost converters to provide rigorous justification derives from an analysis of an approximate model. Similar results hold for buck and buck-boost converters. An experimental boost converter and a simulated PFC boost support the derived requirement. Keywords

  7. GNP NanocompositeDirect current resistivity

    E-Print Network [OSTI]

    Collins, Gary S.

    and polymer Carbon nanoparticles are highly conductive and shape and size make them attractive choice with suspension for 6 hours: Achieve uniform composite solution and thorough contact between GNP and Polymer rate Want low electrical resistivity and low relative permittivity The Polymer Composite: Polymers

  8. Pacific Direct Current Intertie (PDCI) Upgrade Project

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

    & Reliability Projects Expand Projects Skip navigation links Line Projects Big Eddy-Knight Central Ferry Lower Monumental Grand Coulee Transmission Line Replacement...

  9. 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.

  10. 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)

    2006-08-15

    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

  11. 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)

    1992-01-01

    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.

  12. 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

    2015-01-01

    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).

  13. Demonstration of cathode emittance dominated high bunch charge beams in a DC gun-based photoinjector

    SciTech Connect (OSTI)

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

    2015-03-02

    We present the results of transverse emittance and longitudinal current profile measurements of high bunch charge (?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 emittances 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 and Free Electron Lasers.

  14. Induced Currents, Eddy Currents and

    E-Print Network [OSTI]

    Tobar, Michael

    Lecture 11 Induced Currents, Eddy Currents and Maxwell's Equations 1 Faraday Disk Dynamo F = q Eddy Currents We have learnt that changing magnetic fields can induce electric fields in conductors 108 ms-1 16 #12;In this lecture and the next Eddy Currents: We have covered Sect. 29

  15. Achieving Near Zero SSN Power Delivery Networks by Eliminating Power Planes and Using Constant Current Power Transmission Lines

    E-Print Network [OSTI]

    Swaminathan, Madhavan

    on power supply network caused by DC resistance, 2) Mismatch effect caused by the power transmission line resistor of the power transmission line, the current through the power transmission line induces DC drop Current Power Transmission Lines Suzanne Huh, Daehyun Chung, and Madhavan Swaminathan Interconnect

  16. Cap-and-Trade Modeling and Analysis: Congested Electricity Market Equilibrium

    E-Print Network [OSTI]

    Limpaitoon, Tanachai

    2012-01-01

    network in the DC OPF model without transmission losses. Oila lossless DC load flow model where transmission flows arethe transmission network, we employ a direct current (DC)

  17. KAUAI CEANNEL CURRENTS THESIS SUBMITTED TO TEE GRADUATE

    E-Print Network [OSTI]

    Luther, Douglas S.

    from August L95, through Novem ber 1966. Direct current measurements were made by a Savonius current

  18. Board on Physics and AstronomyBoard on Physics and Astronomy 2101 Constitution Avenue, NW, Washington, DC 20418

    E-Print Network [OSTI]

    -academies.org/bpa August 31, 1999 Dr. Martha Krebs Director Office of Science Department of Energy Washington, DC 20550 Dear Dr. Krebs: National Research Council Chair Dr. Bruce Alberts, in response to your letter and inertial confinement, but the program structures are quite different. The committee does not directly

  19. Quantitative Outgassing studies in DC Electrical breakdown

    E-Print Network [OSTI]

    Levinsen, Yngve Inntjore; Calatroni, Sergio; Taborelli, Mauro; Wünsch, Walter

    2010-01-01

    Breakdown in the accelerating structures sets an important limit to the performance of the CLIC linear collider. Vacuum degradation and subsequent beam instability are possible outcomes of a breakdown if too much gas is released from the cavity surface. Quantitative data of gas released by breakdowns are provided for copper (milled Cu-OFE, as-received and heat-treated), and molybdenum. These data are produced in a DC spark system based on a capacitance charged at fixed energy, and will serve as a reference for the vacuum design of the CLIC accelerating structures.

  20. 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 Home Page on QA:QA J-E-1 SECTIONRobertsdale, Alabama (UtilityInstruments Inc JumpIowa:Minnesota:Daylighting JumpDc's blog Home >

  1. DC Survey 2013 | National Nuclear Security Administration

    National Nuclear Security Administration (NNSA)

    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 Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield Municipal Gas &SCE-SessionsSouthReport for the t-) S/,,5 'a CConversion |National Laser UserDC

  2. Washington DC | 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 Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop IncIowa (Utility Company)Idaho)Vossloh Kiepe JumpWarana Group ofDC Home Linked

  3. Digital Sliding Mode Pulsed Current Averaging IC Drivers for High Brightness Light Emitting Diodes

    E-Print Network [OSTI]

    Lehman, Brad

    to the load. A variable frequency boost converter in Discontinuous Conduction Mode (DCM) has been used algorithm of the inductor current variations for a digitally controlled DC-DC boost converter operating in Continuous Conduction Mode. [10] describes a microcontroller based digital boost converter for a RGB

  4. 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 A proof-of-concept military advanced mobile generator set has been developed. The military generator set

  5. A Reachability-Based Method for Large-Signal Behavior Verification of DC-DC Converters

    E-Print Network [OSTI]

    Liberzon, Daniel

    -loop, large-signal system behavior verification, and iv) switching detail modeling. In open-loop, large´inguez-Garc´ia, Member, IEEE Abstract--A method for large-signal behavior verification of power electronics DC behavior verification, lengthy time-domain simula- tions are conducted to analyze the system response

  6. Electric current locator

    DOE Patents [OSTI]

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

    2012-02-07

    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.

  7. Vehicle Technologies Office Merit Review 2014: DC Fast Charging...

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

    Technologies Office Merit Review 2014: DC Fast Charging Effects on Battery Life and EVSE Efficiency and Security Testing Presentation given by Idaho National Laboratory at 2014...

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

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

    INL Efficiency and Security Testing of EVSE, DC Fast Chargers, and Wireless Charging Systems May 14, 2013 Project ID VSS096 2013 DOE Vehicle Technologies Program Annual Merit...

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

    Energy Savers [EERE]

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

  10. DC Resistivity Survey (Schlumberger Array) At Raft River Geothermal...

    Open Energy Info (EERE)

    Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: DC Resistivity Survey (Schlumberger Array) At Raft River Geothermal Area (1974-1975) Exploration...

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

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

    Testing to support Code & Standards Vehicle Technologies Office Merit Review 2014: DC Fast Charging Effects on Battery Life and EVSE Efficiency and Security Testing Vehicle...

  12. 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...

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

    Open Energy Info (EERE)

    2008 - 2010 Usefulness useful DOE-funding Unknown Exploration Basis Determination of groundwater flux patterns Notes Researchers measured DC resistivity and produced 12 resistivity...

  14. DESIGN AND PERFORMANCE OF PEP DC POWER SYSTEMS

    E-Print Network [OSTI]

    Jackson, T.

    2010-01-01

    DC supplies, with no switchgear interposed between the DCthe only transformers and switchgear in the system, and theycost of transformers and switchgear is eliminated from the

  15. Simulation Study of an Extended Density DC Glow Toroidal Plasma Source

    SciTech Connect (OSTI)

    Granda-Gutierrez, E. E.; Piedad-Beneitez, A. de la; Lopez-Callejas, R.; Godoy-Cabrera, O. G.; Benitez-Read, J. S.; Pacheco-Sotelo, J. O.; Pena-Eguiluz, R.; Mercado-Cabrera, A.; Valencia A, R.; Barocio, S. R.

    2006-12-04

    Conventional wisdom assigns the DC glow discharge regime to plasma currents below {approx}500 mA values, beyond which the discharge falls into the anomalous glow and the turbulent arc regimes. However, we have found evidence that, during toroidal discharges, this barrier can be ostensibly extended up to 800 mA. Thus, a computer simulation has been applied to the evolution of the main electrical characteristics of such a glow discharge plasma in a toroidal vessel in order to design and construct a respective voltage/current controlled source. This should be able to generate a DC plasma in the glow regime with which currents in the range 10-3-100 A can be experimented and 109-1010 cm-3 plasma densities can be achieved to PIII optimization purposes. The plasma is modelled as a voltage-controlled current source able to be turned on whenever the breakdown voltage is reached across the gap between the anode and the vessel wall. The simulation outcome fits well our experimental measurements showing that the plasma current obeys power laws that are dependent on the power current and other control variables such as the gas pressure.

  16. An innovative high-power constant-current pulsed-arc power-supply for a high-density pulsed-arc-plasma ion-source using a LaB{sub 6}-filament

    SciTech Connect (OSTI)

    Ueno, A.; Oguri, H.; Ikegami, K.; Namekawa, Y.; Ohkoshi, K.; Tokuchi, A.

    2010-02-15

    An innovative high-power constant-current (CC) pulsed-arc (PA) power-supply (PS) indispensable for a high-density PA plasma ion-source using a lanthanum hexaboride (LaB{sub 6}) filament was devised by combining a constant-voltage (CV) PA-PS, which is composed of an insulated gate bipolar transistor (IGBT) switch, a CV direct-current (dc) PS and a 270 mF capacitor with a CC-PA-PS, which is composed of an IGBT-switch, a CC-dc-PS and a 400 {mu}H inductor, through the inductor. The hybrid-CC-PA-PS succeeded in producing a flat arc-pulse with a peak power of 56 kW (400 Ax140 V) and a duty factor of more than 1.5%(600 {mu}sx25 Hz) for Japan Proton Accelerator Research Complex (J-PARC) H{sup -} ion-source stably. It also succeeded in shortening the 99% rising-time of the arc-pulse-current to about 20 {mu}s and tilting up or down the arc-pulse-current arbitrarily and almost linearly by changing the setting voltage of its CV-dc-PS.

  17. Design and analysis of a zero-voltage switching scheme for a dc- to-dc converter 

    E-Print Network [OSTI]

    Arun, G.

    1992-01-01

    DESIGN AND ANALYSIS OF A ZERO-VOLTAGE SSVITCHING SCFIE'. tIE FOR A DC-TO-DC CONVERTER A Thesis by G. ARUN Submitted to the Office of Graduate Studies of Texas ARM 1. niversity in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE December 1992 Major Subject: Electrical Engineering DESIGN AND ANALYSIS OE A ZERO-VOLTAGE SWITCHING SCHEME I'OR A DC-TO-DC CONVERTER A Thesis by G. AR(tN Approved as to style and content by: P. Enjeti (Chair of Cornrnitteel C...

  18. 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 Supplier: ABB Railroa d DC Tie USA - Mission, TX 26°1001N9 8°1925W USA - Mission, TX 26°1001N9 8°1925W 21

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

    E-Print Network [OSTI]

    Tan, Chee Wei

    the minimization of power transmission loss in DC-OPF and char- acterize the uniqueness of its solutions. This hasDC Optimal Power Flow: Uniqueness and Algorithms Chee Wei TanÝ , Desmond W. H. Cai£ and Xin LouÝ Ý and transmission loss in a power net- work subject to physical constraints governed by Kirchhoff's and Ohm's law [1

  20. A 3D Magnetic Force Manipulator DC Prototype

    E-Print Network [OSTI]

    North Carolina at Chapel Hill, University of

    A 3D Magnetic Force Manipulator DC Prototype Leandra Vicci Microelectronic Systems Laboratory optical field intensities which interact strongly with many materials and may produce undesired side;Leandra Vicci A 3D Magnetic Force Manipulator DC Prototype 17 October 2001 1 Conceptual design

  1. Read-out electronics for DC squid magnetic measurements

    DOE Patents [OSTI]

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

    2002-01-01

    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.

  2. Peter M. Vallone AAFS Washington, D.C.

    E-Print Network [OSTI]

    Peter M. Vallone AAFS Washington, D.C. February 23, 2008 http://www.cstl.nist.gov/biotech available for the purpose. Our publications and presentations are made available at: http://www.cstl.nist.gov/biotech/strbase/NISTpub.htm #12;Peter M. Vallone AAFS Washington, D.C. February 23, 2008 http://www.cstl.nist.gov/biotech

  3. Tutorial, GECCO'05, Washington D.C. Fitness Approximation

    E-Print Network [OSTI]

    Yang, Shengxiang

    1 Tutorial, GECCO'05, Washington D.C. Fitness Approximation in Evolutionary Computation Yaochu Jin Honda Research Institute Europe Khaled Rasheed University of Georgia Tutorial, GECCO'05, Washington D expensive fitness evaluations Tutorial, GECCO'05, Washington D.C. Fitness Approximation Methods · Problem

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

    Broader source: Energy.gov [DOE]

    The 2014 National Small Business Federal Contracting Summit - DC Fall Conference is presented jointly by the National Association of Small Business Contractors (the Supplier Council of The American Small Business Chamber of Commerce) and the U.S. Women's Chamber of Commerce in Washington DC.

  5. 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.

    2012-10-20

    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.

  6. 1668 IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 27, NO. 4, APRIL 2012 55-kW Variable 3X DC-DC Converter for Plug-in

    E-Print Network [OSTI]

    Tolbert, Leon M.

    vehicle (HEV) traction drives. The boost converter used in commercial HEVs meets with obstacles when is shown in Fig. 1. In this system, the dc-dc converter boosts the battery voltage from 244 V to three op series-parallel HEV. speed and power demand of the vehicle. In this traditional dc- dc boost converter

  7. 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

    2007-12-31

    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.

  8. Abstract--A design method for digital controller of PWM DC-DC converters was developed, tested by simulations and

    E-Print Network [OSTI]

    domain transformation and discretization. A digital PID controller for a Buck type converter domain and the sampled data domain (via the various transformation algorithms), a digital compensatorAbstract-- A design method for digital controller of PWM DC-DC converters was developed, tested

  9. Application to Export Electric Energy OE Docket No. EA-351 DC...

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

    1 DC Energy Dakota, LLC Application to Export Electric Energy OE Docket No. EA-351 DC Energy Dakota, LLC Application from DC Energy Dakota, LLC to export electric energy to Canada...

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

    Energy Savers [EERE]

    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...

  11. 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

    2011-06-02

    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, andmore »hence the effect of the DC mode, explicitly only in the Poisson equation.« less

  12. Current Titles

    SciTech Connect (OSTI)

    Various

    2006-06-01

    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.

  13. Thermoelectric DC conductivities and Stokes flows on black hole horizons

    E-Print Network [OSTI]

    Elliot Banks; Aristomenis Donos; Jerome P. Gauntlett

    2015-07-15

    We consider a general class of electrically charged black holes of Einstein-Maxwell-scalar theory that are holographically dual to conformal field theories at finite charge density which break translation invariance explicitly. We examine the linearised perturbations about the solutions that are associated with the thermoelectric DC conductivity. We show that there is a decoupled sector at the black hole horizon which must solve generalised Stokes equations for a charged fluid. By solving these equations we can obtain the DC conductivity of the dual field theory. For one-dimensional lattices we solve the fluid equations to obtain closed form expressions for the DC conductivity in terms of the solution at the black hole horizon. We also determine the leading order DC conductivity for lattices that can be expanded as a perturbative series about translationally invariant solutions.

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

    DOE Patents [OSTI]

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

    1984-04-27

    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.

  15. National Science Bowl Brings Best and Brightest to DC

    Broader source: Energy.gov [DOE]

    The National Science Bowl Finals in Washington D.C. April 27 to 30 pit 113 high and middle school teams against one another answering questions Jeopardy-style about biology, chemistry, earth science, physics, astronomy, and math.

  16. Thermoelectric DC conductivities and Stokes flows on black hole horizons

    E-Print Network [OSTI]

    Banks, Elliot; Gauntlett, Jerome P

    2015-01-01

    We consider a general class of electrically charged black holes of Einstein-Maxwell-scalar theory that are holographically dual to conformal field theories at finite charge density which break translation invariance explicitly. We examine the linearised perturbations about the solutions that are associated with the thermoelectric DC conductivity. We show that there is a decoupled sector at the black hole horizon which must solve generalised Stokes equations for a charged fluid. By solving these equations we can obtain the DC conductivity of the dual field theory. For one-dimensional lattices we solve the fluid equations to obtain closed form expressions for the DC conductivity in terms of the solution at the black hole horizon. We also determine the leading order DC conductivity for lattices that can be expanded as a perturbative series about translationally invariant solutions.

  17. Thermoelectric DC conductivities with momentum dissipation from higher derivative gravity

    E-Print Network [OSTI]

    Long Cheng; Xian-Hui Ge; Zu-Yao Sun

    2015-04-28

    We present a mechanism of momentum relaxation in higher derivative gravity by adding linear scalar fields to the Gauss-Bonnet theory. We analytically computed all of the DC thermoelectric conductivities in this theory by adopting the method given by Donos and Gauntlett in [arXiv:1406.4742]. The results show that the DC electric conductivity is not a monotonic function of the effective impurity parameter $\\beta$: in the small $\\beta$ limit, the DC conductivity is dominated by the coherent phase, while for larger $\\beta$, pair creation contribution to the conductivity becomes dominant, signaling an incoherent phase. In addition, the DC heat conductivity is found independent of the Gauss-Bonnet coupling constant.

  18. Thermoelectric DC conductivities and Stokes flows on black hole horizons

    E-Print Network [OSTI]

    Elliot Banks; Aristomenis Donos; Jerome P. Gauntlett

    2015-10-11

    We consider a general class of electrically charged black holes of Einstein-Maxwell-scalar theory that are holographically dual to conformal field theories at finite charge density which break translation invariance explicitly. We examine the linearised perturbations about the solutions that are associated with the thermoelectric DC conductivity. We show that there is a decoupled sector at the black hole horizon which must solve generalised Stokes equations for a charged fluid. By solving these equations we can obtain the DC conductivity of the dual field theory. For Q-lattices and one-dimensional lattices we solve the fluid equations to obtain closed form expressions for the DC conductivity in terms of the solution at the black hole horizon. We also determine the leading order DC conductivity for lattices that can be expanded as a perturbative series about translationally invariant solutions.

  19. The impact of argon admixture on the c-axis oriented growth of direct current magnetron sputtered Sc{sub x}Al{sub 1?x}N thin films

    SciTech Connect (OSTI)

    Mayrhofer, P. M.; Bittner, A.; Schmid, U.; Eisenmenger-Sittner, C.; Stöger-Pollach, M.

    2014-05-21

    The piezoelectric properties of wurtzite aluminium nitride (w-AlN) are enhanced by alloying with scandium (Sc), thus offering superior properties for applications in micro electro-mechanical systems devices. Sc{sub x}Al{sub 1?x}N thin films have been prepared by DC reactive magnetron sputtering on Si (100) substrates from a single target. When targeting a concentration range from x?=?0 up to x?=?0.15, the preparation conditions have been optimized by varying the Ar/N{sub 2} ratio in the sputtering gas. To incorporate an increasing Sc concentration, a higher Ar/N{sub 2} ratio has to be applied during the deposition process. Hence, the argon concentration in the sputtering gas becomes a crucial parameter for microstructure-related parameters. To determine phase purity, degree of c-axis orientation, lattice parameter, and grain size, the Sc{sub x}Al{sub 1?x}N thin films were investigated by techniques, such as scanning electron microscopy, transmission electron microscopy, and X-ray diffraction.

  20. Control method for peak power delivery with limited DC-bus voltage

    DOE Patents [OSTI]

    Edwards, John; Xu, Longya; Bhargava, Brij B.

    2006-09-05

    A method for driving a neutral point-clamped multi-level voltage source inverter supplying a synchronous motor is provided. A DC current is received at a neutral point-clamped multi-level voltage source inverter. The inverter has first, second, and third output nodes. The inverter also has a plurality of switches. A desired speed of a synchronous motor connected to the inverter by the first second and third nodes is received by the inverter. The synchronous motor has a rotor and the speed of the motor is defined by the rotational rate of the rotor. A position of the rotor is sensed, current flowing to the motor out of at least two of the first, second, and third output nodes is sensed, and predetermined switches are automatically activated by the inverter responsive to the sensed rotor position, the sensed current, and the desired speed.

  1. Design and analysis of 5045 S-band klystron DC electron gun

    E-Print Network [OSTI]

    Rehman, Abdul; Zhou, Z

    2015-01-01

    The design and performance analysis of DC electron gun for 5045 S-band klystron has been worked out using SLAC beam trajectory program (EGUN) and Computer Simulation Technology Particle Studio (CST-PS), Codes. Specifications of electron gun were focused on beam; current, perveance, size and emittance. Optimized beam; current, perveance, diameter and emittance were 414.00A, 2.00uP, 26.82 mm and 103.10 pi mm mrad, respectively. Furthermore, the optimized characteristic parameters of the gun were also calculated and compared with the simulated and experimental values which were in agreement. Accuracy of simulation was verified by comparison of emitted beam current which has error of zero percent.

  2. Design and analysis of 5045 S-band klystron DC electron gun

    E-Print Network [OSTI]

    Abdul Rehman; Munawar Iqbal; Z. Zhou

    2015-12-30

    The design and performance analysis of DC electron gun for 5045 S-band klystron has been worked out using SLAC beam trajectory program (EGUN) and Computer Simulation Technology Particle Studio (CST-PS), Codes. Specifications of electron gun were focused on beam; current, perveance, size and emittance. Optimized beam; current, perveance, diameter and emittance were 414.00A, 2.00uP, 26.82 mm and 103.10 pi mm mrad, respectively. Furthermore, the optimized characteristic parameters of the gun were also calculated and compared with the simulated and experimental values which were in agreement. Accuracy of simulation was verified by comparison of emitted beam current which has error of zero percent.

  3. Role of dc space charge field in the optimization of microwave conversion efficiency from a modulated intense relativistic electron beam

    SciTech Connect (OSTI)

    Xiao, Renzhen; Chen, Changhua; Wu, Ping; Song, Zhimin; Sun, Jun [Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi'an 710024 (China)] [Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi'an 710024 (China)

    2013-12-07

    We demonstrate an efficiency of 70% with 5.1 GW microwave power for a diode voltage of 770 kV and a current modulation coefficient of 1.67 in a klystron-like relativistic backward wave oscillator. The device combines the advantages of reducing electron beam radius, adopting dual-cavity extractor, and introducing two pre-modulation cavities. A large dc space charge field is present due to the conversion of considerable potential energy to kinetic energy at the end of beam-wave interaction region. A nonlinear theory is developed to show that the dc space charge field can increase the current modulation coefficient and microwave conversion efficiency significantly.

  4. Aalborg Universitet Power flow analysis for droop controlled LV hybrid AC-DC microgrids with virtual

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    Aalborg Universitet Power flow analysis for droop controlled LV hybrid AC-DC microgrids controlled LV hybrid AC-DC microgrids with virtual impedance. In Proceedings of the IEEE Power & Energy Interlinking converter PV WT IBS DC microgrid DC microgrid AC microgrid AC Load Figure 1. Structure

  5. 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory of raregovAboutRecoveryplanningCoalSocialFrameworks AppliedCurrent Contracts

  6. Switching power converter Figure 1(a): Switching DC-DC converter with analog voltage-mode control

    E-Print Network [OSTI]

    + ­ RC L Vg 1 2 i + v _ Vref + _ Gc(s) VM = 1 PWM u c Switching power converter H v dTs H = 1 design of digital compensators. I. INTRODUCTION Discrete-time modeling of dc-dc switching converters has IEEE. #12;+ ­ R C L Vg 1 2 i + v _ Vref + _ Gc(z) VM = 1 DPWM u c Switching power converter H v dTs H

  7. Directives - 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation Current HAB PacketDiesel prices continueDileepDirections &Directions

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

    E-Print Network [OSTI]

    Zhang, Yuan; Liang, Yung C.

    2015-01-01

    vessels and vehicles as efficient delivery interconnectsSingapore-Berkeley Building Efficiency and Sustainability in

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

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

    Dam, Oregon. | Photo courtesy of the Energy Department Allison Lantero Allison Lantero Digital Content Specialist, Office of Public Affairs How can I participate? Check out our...

  10. The War of the Currents: AC vs. DC Power | 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield Municipal Gas &SCE- Non-ResidentialAlliantPGE andOfficeMatt RogersnowReno,Department ofElectrical

  11. The War of the Currents: AC vs. DC Power | 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: Alternative FuelsofProgram: Report15 MeetingDevelopmentDepartmentof EnergyThe SunShotTheThe

  12. Automatic System for the D.C. High Voltage Qualification of the Superconducting Electrical Circuits of the LHC Machine

    E-Print Network [OSTI]

    Bozzini, D; Russenschuck, Stephan; Bednarek, M; Jurkiewicz, P; Kotarba, A; Ludwin, J; Olek, S

    2008-01-01

    A d.c. high voltage test system has been developed to verify automatically the insulation resistance of the powering circuits of the LHC. In the most complex case, up to 72 circuits share the same volume inside cryogenic lines. Each circuit can have an insulation fault versus any other circuit or versus ground. The system is able to connect up to 80 circuits and apply a voltage up to 2 kV D.C. The leakage current flowing through each circuit is measured within a range of 1 nA to 1.6 mA. The matrix of measurements allows characterizing the paths taken by the currents and locating weak points of the insulation between circuits. The system is composed of a D.C. voltage source and a data acquisition card. The card is able to measure with precision currents and voltages and to drive up to 5 high voltage switching modules offering 16 channels each. A LabVIEW application controls the system for an automatic and safe operation. This paper describes the hardware and software design, the testing methodology and the res...

  13. Lab 4 -Motor Constants and Sensor Calibration Consider a DC servo motor which is connected to a power supply. The motor inertia is Jm. The rotational

    E-Print Network [OSTI]

    Stanford University

    Lab 4 - Motor Constants and Sensor Calibration PRE-LAB Consider a DC servo motor which is connected to a power supply. The motor inertia is Jm. The rotational damping in the motor is bm. The motor produces a torque Tm = Kmi where Km is the motor's torque constant and i is the current from the power supply. a

  14. Directives System

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

    1998-01-30

    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

  15. What can you do with energy-efficient optics and photonics? Well, for starters... FOOTPRINT CLEAN ENERGY WORK SLOW CLIMATE CHANGE CONSERVATION DIRECT CURRENT EFFICIENT SUN FLEXIBLE FUEL ELECTRON OFF-THE-GRID THERMAL ENERGY ENGINEER ENVIRONMEN

    E-Print Network [OSTI]

    Faure, Claudie

    devices, creating a power plant. Utilize solar energy at night with nanostructured capacitors, and use · ELECTRON · OFF-THE-GRID · THERMAL ENERGY · ENGINEER · ENVIRONMENT · FURNACE · SOLAR POWER · CURRENT SOLAR, PHOTONIC DEVICES FOR EFFICIENT HARVESTING AND CONVERSION OF SOLAR ENERGY DEVICESFORMONITORINGENERGYUSAGE,MONITORINGEXHAUSTGASESANDPOLLUTANTS,ENERGY

  16. Materials with low DC magnetic susceptibility for sensitive magnetic measurements

    E-Print Network [OSTI]

    Khatiwada, Rakshya; Kendrick, Rachel; Khosravi, Marjan; Peters, Michael; Smith, Erick; Snow, Mike

    2015-01-01

    Materials with very low DC magnetic susceptibility have many scientific applications. To our knowledge however, relatively little research has been conducted with the goal to produce a totally nonmagnetic material. This phrase in our case means after spatially averaging over macroscopic volumes, it possesses an average zero DC magnetic susceptibility. We report measurements of the DC magnetic susceptibility of three different types of nonmagnetic materials at room temperature: (I) solutions of paramagnetic salts and diamagnetic liquids, (II) liquid gallium-indium alloys and (III) pressed powder mixtures of tungsten and bismuth. The lowest measured magnetic susceptibility among these candidate materials is in the order of 10^-9 cgs volume susceptibility units, about two orders of magnitude smaller than distilled water. In all cases, the measured concentration dependence of the magnetic susceptibility is consistent with that expected for the weighted sum of the susceptibilities of the separate components within...

  17. Nuclear magnetic resonance experiments with dc SQUID amplifiers

    SciTech Connect (OSTI)

    Heaney, M.B. . Dept. of Physics Lawrence Berkeley Lab., CA )

    1990-11-01

    The development and fabrication of dc SQUIDs (Superconducting QUantum Interference Devices) with Nb/Al{sub 2}O{sub 3}/Nb Josephson junctions is described. A theory of the dc SQUID as a radio-frequency amplifier is presented, with an optimization strategy that accounts for the loading and noise contributions of the postamplifier and maximizes the signal-to-noise ratio of the total system. The high sensitivity of the dc SQUID is extended to high field NMR. A dc SQUID is used as a tuned radio-frequency amplifier to detect pulsed nuclear magnetic resonance at 32 MHz from a metal film in a 3.5 Tesla static field. A total system noise temperature of 11 K has been achieved, at a bath temperature of 4.2 K. The minimum number of nuclear Bohr magnetons observable from a free precession signal after a single pulse is about 2 {times} 10{sup 17} in a bandwidth of 25 kHz. In a separate experiment, a dc SQUID is used as a rf amplifier in a NQR experiment to observe a new resonance response mechanism. The net electric polarization of a NaClO{sub 3} crystal due to the precessing electric quadrupole moments of the Cl nuclei is detected at 30 MHz. The sensitivity of NMR and NQR spectrometers using dc SQUID amplifiers is compared to the sensitivity of spectrometers using conventional rf amplifiers. A SQUID-based spectrometer has a voltage sensitivity which is comparable to the best achieved by a FET-based spectrometer, at these temperatures and operating frequencies.

  18. Characterization of the PvdS-regulated promoter motif in Pseudomonas syringae pv. tomato DC3000 reveals

    E-Print Network [OSTI]

    Myers, Chris

    Characterization of the PvdS-regulated promoter motif in Pseudomonas syringae pv. tomato DC3000S, a group IV sigma factor encoded by Pseudomonas syringae pv. tomato DC3000 (DC3000), a plant pathogen, 2002; Potvin et al., 2008). The model plant pathogen Pseudomonas syringae pv. tomato DC3000 (DC3000

  19. Controlling Chaos in DC/DC Converters Using Optimal Resonant Parametric Perturbation

    E-Print Network [OSTI]

    Tse, Chi K. "Michael"

    perturba- tion method for controlling chaos in a current-mode con- trolled buck-boost converter of control. Specifically we make a chaotic buck-boost converter operate in an unstable period-1 orbit by a more complicated feedback chaos control method. II. CURRENT-MODE CONTROLLED BUCK-BOOST CONVERTER A

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

    E-Print Network [OSTI]

    Kimball, Jonathan W.

    A Digitally Implemented Photovoltaic Simulator with a Double Current Mode Controller Jie Zhao-DC converter-based photovoltaic (PV) simulator which emulates the output characteristics of a real solar panel. Keyword ­ digital control, photovoltaic simulator, predictive current mode control, solar panel IV curve

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

    E-Print Network [OSTI]

    Simões, Marcelo Godoy

    to open-circuit legs. The criti- cism against a higher number of phases is because of its more complex

  2. dc_Grainger.pdf Page 1 of 6 Jan. 2013 Direct Connect

    E-Print Network [OSTI]

    Nicholson, Bruce J.

    of inactivity on the vendor's site, your browser session with Grainger can time out, causing you to lose items and Services page, click on Grainger to "punch out" to the vendor's website. Overview of the Vendor's Website Once you punch out of PeopleSoft, the first page you will see is Grainger's Quick Item Entry page. Here

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

    E-Print Network [OSTI]

    Zhang, Yuemin

    1993-01-01

    the wanted output voltage. Reference [14] proposed three schemes: Sr(~t) is 9 pulses per half cycle, Ss(~t) is 7 pulses per half cycle, and Ss(wt) is just I pulse per half cycle. Then author reached the conclusion that Sr(ut) is the best choice. Reference... in Figure 4. B. ) is given as r t's Sr = J V~sin~tdt &a 1. 17 V (cos wt~ ? cos cdts) According to the principle of DPWM, Sr should be equal to Sr. Then Vm VELDT = ? (cos at~ ? cos its) 1. 18 Since we only have one equation(Eq. 1. 18) and two unknowns...

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

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01

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

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

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01

    Energy Storage While the capacity of net-metered grid-grid is much more costly and complex, with the need for energy storage

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

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01

    solar-energy-news/9344-us-solar-market-insight-report-strong-us- solar-industry-growth-for-first-half-of-2010.html EMerge Alliance.

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

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01

    wp-content/uploads/2010/07/IREC-Solar-Market-Trends-Report-solarpv.html NCSC & IREC. Database of State Incentives for

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

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01

    energy savings benefits for EV charging, to the extent thatvehicles from rectified AC, EV charging would be more simplyAlliance could accommodate EV charging; SAE International is

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

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01

    along with 22 kWh of battery storage. This study by Baek etpower, but the cost of battery storage per unit of loadMargolis [37], local battery storage for building-sited PV,

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

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01

    Ridder, and D. Six, Electricity storage for grid-connectedvehicle (EV) loads, electricity storage, and load shiftinghave identical electricity storage systems in configurations

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

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01

    Buildings. in Green Building Power Forum. 2011. San Jose,for Green Building, in Green Building Power Forum 2011: Sanof the Darnell Group’s Green Building Power Forum and Smart

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

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01

    CA. Sherwood, L. , U.S. Solar Market Trends 2009, 2010,uploads/2010/07/IREC-Solar-Market-Trends-Report- 2010_7-27-Industries Association, U.S. Solar Market Insight(TM): 2010

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

    E-Print Network [OSTI]

    Sulistyono, Widodo

    1994-01-01

    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...

  14. D.C. Water Resource Research Center Annual Technical Report

    E-Print Network [OSTI]

    strengthening a credible program. Proposals submitted to USGS for the 2002 fiscal year was approved and funding to the success of the Institute. Hence, the goals of 2002 fiscal year will continue to fiscal 2003 while DC water resources information has been significantly delayed because UDC website, which hosts WRRI

  15. DC WRRC Report No. 59 DEVELOPMENT OF FREQUENCY

    E-Print Network [OSTI]

    District of Columbia, University of the

    #12;DC WRRC Report No. 59 DEVELOPMENT OF FREQUENCY FUNCTIONS FOR URBAN NON-POINT SOURCE RISK THE CATHOLIC UNIVERSITY OF AMERICA "This work on which this report is based was supported in part by funds guidance during the entire course of the work. Ms. Cathy Saunders served as research assistant

  16. DC WRRC Report No. 139 BOOK OF ABSTRACTS

    E-Print Network [OSTI]

    District of Columbia, University of the

    Washington, DC 20008 , (202) 274- 6400 #12;Table of Contents Preface i I. Social Sciences 1 II. Ground Water THE FEDERAL WATER POLLUTION CONTROL ACT AMENDMENTS OF 1972 Lieber, H. WRRC Report No. 17 DESCRWWRS: Management 208 of the Clean Water Act was examined. The accomplishments and failures of the 208 plans were

  17. 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

  18. Winter Break Trip 2014 New York City & Washington DC

    E-Print Network [OSTI]

    Hutcheon, James M.

    Winter Break Trip 2014 New York City & Washington DC Tentative Trip Information December 13/Meadowlands 575 Park Plaza Drive Secaucus, NJ 07094 (201) 422-9480 Hotel is located 3 miles west of New York City for departure at 5pm. · Public Transportation to and from the city o Bus stop is at NW E ST & NW New Jersey Ave

  19. HYBRID DC ACCURATE CHARGE AMPLIFIER FOR LINEAR PIEZOELECTRIC POSITIONING

    E-Print Network [OSTI]

    Fleming, Andrew J.

    the diverse literature in- volving piezoelectric applications is the problem of hysteresis (Adriaens et alHYBRID DC ACCURATE CHARGE AMPLIFIER FOR LINEAR PIEZOELECTRIC POSITIONING Andrew J. Fleming, S. O, Australia 2308 Abstract: Piezoelectric transducers are known to exhibit less hysterisis when driven

  20. DC WRRC Report No. 170 Program ReportAnnual

    E-Print Network [OSTI]

    District of Columbia, University of the

    the people living in the north east of Washington, D.C. and measured the degree of their interest products constitute their endorsement by the United States Government. #12;The project entitled "A Pilot of groundwater inflows requires a knowledge of the hydraulic conductivity or permeability of the sediments

  1. Qualifying Exam Presentation: DC Discharge Studies Using PIC-MCC

    E-Print Network [OSTI]

    Wurtele, Jonathan

    Qualifying Exam Presentation: DC Discharge Studies Using PIC-MCC Jeffrey Hammel Department during cylindrical magnetron sputtering To assess the applicability of the PIC-MCC method for modeling;Presentation Overview I. Introduction II. Theory A. Paschen's Law B. Positive Column III. PIC-MCC Simulations A

  2. D.C. Water Resources Research Center Annual Technical Report

    E-Print Network [OSTI]

    of DC municipal drinking water quality through random sampling and testing of residential homes that could literally transform the lives of people, especially in the area of water availability. Mr. David. The Institute and the Cooperative Extension Service also added a solar powered weather station to the site

  3. 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.

  4. DC powerline communication system using a transmission line transformer for high degree of freedom applications

    E-Print Network [OSTI]

    Wade, Eric R. (Eric Randolph), 1978-

    2004-01-01

    A new type of powerline communication is developed to reduce cable requirements for robotic, electromechanical, and vehicular systems. A DC power bus line connecting a DC power supply to motor drives and sensor units is ...

  5. If you reside in WASHINGTON, DC - MD -VA - WV your salary will...

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

    If you are employed in the WASHINGTON, DC Metropolitan Area (D.C., Baltimore, Northern VA, Eastern WV, and Southern PA) your salary will range from: Pay Band Pay Plan(s) Minimum...

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

    Energy Savers [EERE]

    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. on Energy...

  7. D.C. Middle and High School Students Get a Chance to Experience...

    Energy Savers [EERE]

    D.C. Middle and High School Students Get a Chance to Experience the Regional Science Bowl Competition Setting D.C. Middle and High School Students Get a Chance to Experience the...

  8. Impedance Control Network Resonant dc-dc Converter for Wide-Range High-Efficiency Operation

    E-Print Network [OSTI]

    Lu, Jie

    This paper introduces a new resonant converter architecture that utilizes multiple inverters and a lossless impedance control network (ICN) to maintain zero voltage switching (ZVS) and near zero current switching (ZCS) ...

  9. Fig.1: Digital Controller with modified buck-boost converter LOAD-INTERACTIVE STEERED-INDUCTOR DC-DC

    E-Print Network [OSTI]

    Prodiæ, Aleksandar

    Fig.1: Digital Controller with modified buck-boost converter LOAD-INTERACTIVE STEERED-INDUCTOR DC-inverting buck- boost. Transient response results show that, compared to standard converters with near-inverting buck-boost converter, i.e. steered-inductor buck-boost, a digital controller, and a communication block

  10. Directions & Maps

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation Current HAB PacketDiesel prices continueDileepDirections & Maps Directions

  11. Directions to Berkeley Lab

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation Current HAB PacketDiesel prices continueDileepDirections & MapsDirections

  12. 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

  13. Potential Federal On-Site Solar Aggregation in Washington, D.C., and Maryland

    Broader source: Energy.gov [DOE]

    Presentation describes potential Federal on-site solar aggregation opportunities in Washington, D.C., and Maryland.

  14. 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.

  15. Demonstration of LED Retrofit Lamps at the Smithsonian Art Museum, Washington, DC

    SciTech Connect (OSTI)

    Miller, N. J.; Rosenfeld, S. M.

    2012-06-01

    GATEWAY program report on a demonstration of LED retrofit lamps at the Smithsonian American Art Museum in Washington, DC.

  16. Sputter target erosion and its effects on long duration DC magnetron sputter coating

    E-Print Network [OSTI]

    Schoff, Michael Elliott

    2009-01-01

    Duration DC Magnetron Sputter Coating A thesis submitted in1 II. Sputter Coating24 VII. Coating Rate vs.

  17. Current balancing for battery strings

    DOE Patents [OSTI]

    Galloway, James H. (New Baltimore, MI)

    1985-01-01

    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.

  18. 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation Current HAB PacketDiesel prices continueDileepDirections Management's

  19. 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation Current HAB PacketDiesel prices continueDileepDirections

  20. A nonlinear robust HVDC control for a parallel AC/DC power system

    E-Print Network [OSTI]

    Qu, Zhihua

    recognized that, through an HVDC transmission line, fast electronic control can be applied on the DC power, controlling DC line transmission power can improve stability of the AC system after a major disturbanceA nonlinear robust HVDC control for a parallel AC/DC power system Hongzhi Cai a , Zhihua Qu b

  1. Towards Building an Optimal Demand Response Framework for DC Distribution Networks

    E-Print Network [OSTI]

    Mohsenian-Rad, Hamed

    Towards Building an Optimal Demand Response Framework for DC Distribution Networks Hamed Mohsenian, an optimization-based foundation is proposed for demand response in DC distribution networks in presence to assess the performance and to gain insights into the proposed demand-response paradigm. Keywords: DC

  2. Aalborg Universitet Generation-Side Power Scheduling in a Grid-Connected DC Microgrid

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    Aalborg Universitet Generation-Side Power Scheduling in a Grid-Connected DC Microgrid Hernández). Generation-Side Power Scheduling in a Grid-Connected DC Microgrid. In IEEE ICDCM 2015. IEEE. General rights.aau.dk on: juli 04, 2015 #12;Generation-Side Power Scheduling in a Grid-Connected DC Microgrid Adriana C

  3. Aalborg Universitet Modeling, Stability Analysis and Active Stabilization of Multiple DC-Microgrids Clusters

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    Aalborg Universitet Modeling, Stability Analysis and Active Stabilization of Multiple DC-Microgrids and Active Stabilization of Multiple DC-Microgrids Clusters. In Proceedings of the 2014 IEEE International of Multiple DC-Microgrid Clusters," in Proc. IEEE International Energy Conference (EnergyCon'14), 2014

  4. Aalborg Universitet Agent-based distributed hierarchical control of dc microgrid systems

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    Aalborg Universitet Agent-based distributed hierarchical control of dc microgrid systems Meng, J. M., & Dragicevic, T. (2014). Agent-based distributed hierarchical control of dc microgrid systems-BASED DISTRIBUTED HIERARCHICAL CONTROL OF DC MICROGRID SYSTEMS Lexuan Meng, Tomislav Dragicevic, Josep M. Guerrero

  5. OLENDER REPORTING, INC. 1100 Connecticut Avenue NW, #810, Washington, DC 20036

    E-Print Network [OSTI]

    1 OLENDER REPORTING, INC. 1100 Connecticut Avenue NW, #810, Washington, DC 20036 Washington: 202 Avenue17 Washington, D.C.18 19 20 21 22 #12;2 OLENDER REPORTING, INC. 1100 Connecticut Avenue NW, #810 #12;3 OLENDER REPORTING, INC. 1100 Connecticut Avenue NW, #810, Washington, DC 20036 Washington: 202

  6. 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 Meeting, 2005 www.ntnu.no Federico Zenith, Sigurd Skogestad, Control of a Fuel-Cell Powered DC Electric Vehicle Motor #12;2 Outline 1) Control of Fuel Cells--Status 2) Dynamic Modelling of Fuel Cells 3) DC

  7. Dynamics of CN+alkane reactions by crossed-beam dc slice imaging

    SciTech Connect (OSTI)

    Huang Cunshun; Li Wen; Estillore, Armando D.; Suits, Arthur G.

    2008-08-21

    The hydrogen atom abstraction reactions of CN (X {sup 2}{sigma}{sup +}) with alkanes have been studied using the crossed molecular beam technique with dc slice ion imaging at collision energies of 7.5 and 10.8 kcal/mol. The product alkyl radical images were obtained via single photon ionization at 157 nm for the reactions of CN (X {sup 2}{sigma}{sup +}) with n-butane, n-pentane, n-hexane, and cyclohexane. From analysis of the images, we obtained the center-of-mass frame product angular distributions and translational energy distributions directly. The results indicate that the products are largely backscattered and that most of the available energy ({approx}80%-85%) goes to the internal energy of the products. The reaction dynamics is discussed in light of recent kinetics data, theoretical calculations, and results for related halogen and oxygen atom reactions.

  8. Direct torque control of permanent magnet synchronous motors with non-sinusoidal back-EMF 

    E-Print Network [OSTI]

    Ozturk, Salih Baris

    2009-05-15

    This work presents the direct torque control (DTC) techniques, implemented in four- and six-switch inverter, for brushless dc (BLDC) motors with non-sinusoidal back- EMF using two and three-phase conduction modes. First of all, the classical direct...

  9. Multilevel cascade voltage source inverter with separate DC sources

    DOE Patents [OSTI]

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

    1997-06-24

    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.

  10. Multilevel cascade voltage source inverter with seperate DC sources

    DOE Patents [OSTI]

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

    1997-01-01

    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.

  11. Multilevel cascade voltage source inverter with seperate DC sources

    DOE Patents [OSTI]

    Peng, Fang Zheng; Lai, Jih-Sheng

    2001-04-03

    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.

  12. Multilevel cascade voltage source inverter with seperate DC sources

    DOE Patents [OSTI]

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

    2002-01-01

    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.

  13. Impedance Control Network Resonant dc-dc Converter for Wide-Range High-Efficiency Operation

    E-Print Network [OSTI]

    Perreault, Dave

    voltages and output power. The ICN converter architecture enables increase in switching frequency (hence to maintain desirable circuit waveforms (e.g., ZVS/ZCS switching and minimum conduction current) as power some widely-used design and control techniques. One common means of controlling resonant soft-switched

  14. AVTA: Battery Testing- DC Fast Charging's Effects on PEV Batteries

    Broader source: Energy.gov [DOE]

    The Vehicle Technologies Office's Advanced Vehicle Testing Activity carries out testing on a wide range of advanced vehicles and technologies on dynamometers, closed test tracks, and on-the-road. These results provide benchmark data that researchers can use to develop technology models and guide future research and development. The following report describes DC fast charging's effects on plug-in electric vehicle batteries. This research was conducted by Idaho National Laboratory.

  15. dc-plasma-sprayed electronic-tube device

    DOE Patents [OSTI]

    Meek, T.T.

    1982-01-29

    An electronic tube and associated circuitry which is produced by dc plasma arc spraying techniques is described. The process is carried out in a single step automated process whereby both active and passive devices are produced at very low cost. The circuitry is extremely reliable and is capable of functioning in both high radiation and high temperature environments. The size of the electronic tubes produced are more than an order of magnitude smaller than conventional electronic tubes.

  16. Report on Non-Contact DC Electric Field Sensors

    SciTech Connect (OSTI)

    Miles, R; Bond, T; Meyer, G

    2009-06-16

    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.

  17. USCOMM-WB-DC PRELIMZNARY REPORT OH HURRICANE DAISY

    E-Print Network [OSTI]

    QC 945.2 .D3 H8 1958 c.2 #12;#12;USCOMM-WB-DC #12;PRELIMZNARY REPORT OH HURRICANE DAISY AWGUST 24-29, 1958 Hurricane "Daisy", intense but small in area, was detected as a tropical storm about 300 miles into a hurricane on August 25. A u g u s t 27 it drifted very slowly northward. coast increased. the Atlantic off

  18. 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: AlternativeCommunication3-EDepartment ofArizona EnergyHampshire EnergyOregonTexasWashington DC

  19. Alternating current long range alpha particle detector

    DOE Patents [OSTI]

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

    1993-02-16

    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.

  20. Using Nyquist or Nyquist-Like Plot to Predict Three Typical Instabilities in DC-DC Converters

    E-Print Network [OSTI]

    Fang, Chung-Chieh

    2012-01-01

    By transforming an exact stability condition, a new Nyquist-like plot is proposed to predict occurrences of three typical instabilities in DC-DC converters. The three instabilities are saddle-node bifurcation (coexistence of multiple solutions), period-doubling bifurcation (subharmonic oscillation), and Neimark bifurcation (quasi-periodic oscillation). In a single plot, it accurately predicts whether an instability occurs and what type the instability is. The plot is equivalent to the Nyquist plot, and it is a useful design tool to avoid these instabilities. Nine examples are used to illustrate the accuracy of this new plot to predict instabilities in the buck or boost converter with fixed or variable switching frequency.

  1. Using Nyquist or Nyquist-Like Plot to Predict Three Typical Instabilities in DC-DC Converters

    E-Print Network [OSTI]

    Chung-Chieh Fang

    2012-04-09

    By transforming an exact stability condition, a new Nyquist-like plot is proposed to predict occurrences of three typical instabilities in DC-DC converters. The three instabilities are saddle-node bifurcation (coexistence of multiple solutions), period-doubling bifurcation (subharmonic oscillation), and Neimark bifurcation (quasi-periodic oscillation). In a single plot, it accurately predicts whether an instability occurs and what type the instability is. The plot is equivalent to the Nyquist plot, and it is a useful design tool to avoid these instabilities. Nine examples are used to illustrate the accuracy of this new plot to predict instabilities in the buck or boost converter with fixed or variable switching frequency.

  2. Abstract--Emerging high-end portable electronics demand on-chip integration of high-performance dc-dc power supplies not

    E-Print Network [OSTI]

    Rincon-Mora, Gabriel A.

    series resistance (ESR) output capacitors, it is not clear how it applies to boost converters boost converter. Experimental results verified the switching supply was stable across 1-30µH, 1-350µ variation to less than 27%. Index Terms--differential control, boost dc-dc converter I. INTRODUCTION

  3. SoC Energy Savings = Reduce+Reuse+Recycle: A Case Study Using a 660MHz DC-DC Converter with Integrated Output Filter

    E-Print Network [OSTI]

    Lemieux, Guy

    that requires careful planning of the interface between the provider and receptor of the energy. In this paper between energy provider and receptor. Since fully integrated on-chip regulators are usually inefficientSoC Energy Savings = Reduce+Reuse+Recycle: A Case Study Using a 660MHz DC-DC Converter

  4. 2004 35Ih Annual IEEE Power Elearonics Specialisrs Conference Aachen, Germany,2004 Modeling of Quantization Effects in Digitally Controlled DC-DC Converters

    E-Print Network [OSTI]

    Prodiæ, Aleksandar

    : {hpeng,maksimov)@colorado.edu Abstract- In digitally controlled DC-DC converters with a single voltage variations, programmability, reduction or elimination of external passive components, as well a conservative hound for the limit-cycle oscillation amplitude, while Section VI11 summarizes the conclusions. 11

  5. 26.2 Single-Inductor Dual-Input Dual-Output Buck-Boost Fuel Cell-Li Ion Charging DC-DC Converter Supply

    E-Print Network [OSTI]

    Rincon-Mora, Gabriel A.

    1 26.2 Single-Inductor Dual-Input Dual-Output Buck-Boost Fuel Cell-Li Ion Charging DC-DC Converter battery with its energy-dense counterpart like the fuel cell (FC) improves micro-scale integration [2]. As a result, buck or boost single-inductor, dual-input, dual-output (SIDIDO) converters enjoy

  6. Abstract -This paper presents the coordinated control of distributed energy storage systems (DESSs) in DC micro-grids.

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    ) in DC micro-grids. In order to balance the state-of-charge (SoC) of each energy storage unit (ESU--Droop control; distributed energy storage system (DESS); DC micro-grids; state-of-charge (SoC) I. INTRODUCTION and more popularity [1]. Nowadays DC micro-grids are becoming more attractive with the raise of DC power

  7. 650 IEEE TRANSACTIONS ON POWER DELIVERY, VOL. 26, NO. 2, APRIL 2011 Hourly Scheduling of DC Transmission Lines in

    E-Print Network [OSTI]

    Fu, Yong

    ). The impact of VSC-DC transmission system on the economics and the security of integrated ac/dc transmission will determine the optimal hourly schedule of controllable VSC-DC transmission systems in electricity markets;LOTFJOU et al.: HOURLY SCHEDULING OF DC TRANSMISSION LINES 651 , Vector of real and reactive power

  8. DRIVING DIRECTIONS

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit theCovalent Bonding Low-Cost2 DOE HQSiteo n n eDPFJ.D.DRIVING DIRECTIONS

  9. Direct Frisk

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit theCovalent BondingMeetingDifferences BetweenDirac ChargeSolarDirect

  10. Request to Cancel Department of Energy (DOE) Order 350.2B, Use of Management and Operating or other Facility Management Contractor Employees for Services to DOE in the Washington D.C. Area

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

    2015-11-23

    DOE is canceling this directive and its associated DOE-wide mandated requirements in recognition of Departmental management and oversight improvements of Headquarters sponsored assignments to the Washington D.C. area and opting to implement as program specific risk based management approach to these actions.

  11. Materials with low DC magnetic susceptibility for sensitive magnetic measurements

    E-Print Network [OSTI]

    Rakshya Khatiwada; Lawrence Dennis; Rachel Kendrick; Marjan Khosravi; Michael Peters; Erick Smith; Mike Snow

    2015-06-30

    Materials with very low DC magnetic susceptibility have many scientific applications. To our knowledge however, relatively little research has been conducted with the goal to produce a totally nonmagnetic material. This phrase in our case means after spatially averaging over macroscopic volumes, it possesses an average zero DC magnetic susceptibility. We report measurements of the DC magnetic susceptibility of three different types of nonmagnetic materials at room temperature: (I) solutions of paramagnetic salts and diamagnetic liquids, (II) liquid gallium-indium alloys and (III) pressed powder mixtures of tungsten and bismuth. The lowest measured magnetic susceptibility among these candidate materials is in the order of 10^-9 cgs volume susceptibility units, about two orders of magnitude smaller than distilled water. In all cases, the measured concentration dependence of the magnetic susceptibility is consistent with that expected for the weighted sum of the susceptibilities of the separate components within experimental error. These results verify the Wiedemann additivity law and thereby realize the ability to produce materials with small but tunable magnetic susceptibility. For our particular scientific application, we are also looking for materials with the largest possible number of neutrons and protons per unit volume. The gallium-indium alloys fabricated and measured in this work possess to our knowledge the smallest ratio of volume magnetic susceptibility to nucleon number density per unit volume for a room temperature liquid, and the tungsten-bismuth pressed powder mixtures possess to our knowledge the smallest ratio of volume magnetic susceptibility to nucleon number density per unit volume for a room temperature solid. This ratio is a figure of merit for a certain class of precision experiments that search for possible exotic spin-dependent forces of Nature.

  12. Integrated Solar Power Converters: Wafer-Level Sub-Module Integrated DC/DC Converter

    SciTech Connect (OSTI)

    2012-02-09

    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.

  13. Positron lifetime spectrometer using a DC positron beam

    DOE Patents [OSTI]

    Xu, Jun; Moxom, Jeremy

    2003-10-21

    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.

  14. Hardwired Control Changes For NSTX DC Power Feeds

    SciTech Connect (OSTI)

    Ramakrishnan, S.

    2013-06-28

    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 __________________________________________________

  15. Heteroepitaxial Ge-on-Si by DC magnetron sputtering

    SciTech Connect (OSTI)

    Steglich, Martin; Schrempel, Frank; Füchsel, Kevin; Kley, Ernst-Bernhard; Patzig, Christian; Berthold, Lutz; Höche, Thomas; Tünnermann, Andreas; Fraunhofer Institute for Applied Optics and Precision Engineering IOF, Albert-Einstein-Str. 7, 07745 Jena

    2013-07-15

    The growth of Ge on Si(100) by DC Magnetron Sputtering at various temperatures is studied by Spectroscopic Ellipsometry and Transmission Electron Microscopy. Smooth heteroepitaxial Ge films are prepared at relatively low temperatures of 380°C. Typical Stransky-Krastanov growth is observed at 410°C. At lower temperatures (320°C), films are essentially amorphous with isolated nanocrystallites at the Si-Ge interface. A minor oxygen contamination at the interface, developing after ex-situ oxide removal, is not seen to hinder epitaxy. Compensation of dislocation-induced acceptors in Ge by sputtering from n-doped targets is proposed.

  16. EA-327-A DC Energy, LLC | 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergy A plug-inPPL EnergyPlus, LLC to export electricSilverhill Ltdto export electricDC

  17. EA-351 DC Energy Dakota, LLC | 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergy A plug-inPPL EnergyPlus, LLC to export electricSilverhillSaracenCreditNextEraDC

  18. EA-377 DC Energy Texas | 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergy A plug-inPPL EnergyPlus, LLC to exportEndure Energy,Vitol Inc toDC Energy Texas to

  19. Category: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 QA:QA J-E-1 SECTION JEnvironmentalBowerbank,Cammack Village,8199089°,AnalyticalCuttings Analysis JumpDC Resistivity

  20. Global DC Power System Market Analysis | 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 Home Page on QA:QA J-E-1 SECTION J APPENDIXsource History View New Pages RecentPlant <SilverChange Associates JumpGlobal DC Power

  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 QA:QA J-E-1 SECTION J APPENDIX ECoopButtePower VenturesInformation9) Wind Farm JumpAlum|Cyclone PowerD1DC

  2. Categorical Exclusion Determinations: Washington, D.C. | Department of

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergyTher i n c i p a lCaribElectricSouth Dakota. DOCUMENTSEnergy Washington, D.C.

  3. 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

  4. TRANSPORT PATHWAYS OF THE MAINE COASTAL CURRENT

    E-Print Network [OSTI]

    TRANSPORT PATHWAYS OF THE MAINE COASTAL CURRENT Monica J. Holboke and Daniel R. Lynch September 1996 Abstract The Maine Coastal Current(MCC) is initiated off the eastern coast of Maine and circuits the Gulf of Maine in a counterclockwise direction transporting various nu­ trients, biological species

  5. Cooling efficiency of a brushless direct current stand fan

    E-Print Network [OSTI]

    Yang, Bin; Schiavon, Stefano; Sekhar, Chandra; Cheong, David; Tham, Kwok Wai; Nazaroff, William W

    2015-01-01

    3.1.2. Cooling Fan Efficiency (CFE) index Fig. 5 displaysH, Zhai Y. Enabling energy-efficient approaches to thermalIntroduction of a cooling-fan efficiency index. HVAC&R Res [

  6. Current status and direction of US global warming policy

    SciTech Connect (OSTI)

    Gardiner, D.

    1997-12-31

    The pace and intensity of U.S. global warming efforts have been increasing over the past few years for three main reasons: (1) steady improvement in the underlying science that is in turn strengthening public support for action; (2) the likelihood that the United States will fall short of our national goal of stabilizing greenhouse gas emissions at 1990 levels by the year 2000; and (3) U.S. participation in international negotiations to address global climate change. The expansion of U.S. global warming activities can be seen at the state, federal, and international levels. At the state level, for example, a majority of states have completed greenhouse gas emissions inventories, several have undertaken analyses of mitigation options, and some are already beginning to take action to reduce greenhouse gas emissions. At the federal level, all federal agencies with an interest in global warming are working together to define the likely consequences of continued increases in greenhouse gas emissions, inform the public about Such consequences, and assess the costs and benefits of different response options. Among the response options being assessed are actions to expand the use of energy efficient technologies; new controls on greenhouse gas emissions through -- for example - government standards, regulations, or emissions trading programs; and increased research and development of technologies less dependent on fossil fuels. Finally, at the international level, the United States is continuing to develop the position it will take to the climate change negotiations to be held in Japan this December. Among, other things, we have proposed enforceable emissions targets for developed countries, a strong program of reporting and compliance, new efforts by developing countries to prepare emissions inventories and mitigate emissions, and an international emissions trading program.

  7. Cooling efficiency of a brushless direct current stand fan

    E-Print Network [OSTI]

    Yang, Bin; Schiavon, Stefano; Sekhar, Chandra; Cheong, David; Tham, Kwok Wai; Nazaroff, William W

    2015-01-01

    eq (°C) Front Side Fig. 4. Cooling effect comparison betweenmanikin distance. 3.1.2. Cooling Fan Efficiency (CFE) indexdevices [41-42]. Local cooling for front and side fan-

  8. Cooling efficiency of a brushless direct current stand fan

    E-Print Network [OSTI]

    Yang, Bin; Schiavon, Stefano; Sekhar, Chandra; Cheong, David; Tham, Kwok Wai; Nazaroff, William W

    2015-01-01

    7730 (2005). Moderate thermal environment-determination ofTL. Evaluating thermal environments by using a thermalcontrol over one’s thermal environment can increase comfort,

  9. Direct-Current Resistivity Survey At Kilauea East Rift Geothermal...

    Open Energy Info (EERE)

    Exploration Basis This study was conducted to learn about and model the resistivity structures in the Puna area Notes Two bipole mapping surveys were conducted near well HGP-A....

  10. Direct-Current Resistivity Survey At Kilauea Southwest Rift And...

    Open Energy Info (EERE)

    data acquired on the southwest rift delineated two distinct basement resistivity structures northwest of the rift zone: a high-resistivity basement at approximately 60 m a.s.l,...

  11. Direct-Current Resistivity At Kilauea Southwest Rift And South...

    Open Energy Info (EERE)

    data acquired on the southwest rift delineated two distinct basement resistivity structures northwest of the rift zone: a high-resistivity basement at approximately 60 m a.s.l,...

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

    E-Print Network [OSTI]

    Reber, Paul J.

    and not toward other effortful aims like eating less junk food. He is also likelier to succeed if he believes he in a social vacuum. Like most people, he spends much of every day with others--strangers, class- mates

  13. Stress evolution during growth in direct-current-sputtered zinc...

    Office of Scientific and Technical Information (OSTI)

    IONS; RADIOWAVE RADIATION; SEMICONDUCTOR MATERIALS; SPUTTERING; STOICHIOMETRY; SURFACE COATING; THICKNESS; THIN FILMS; VARIATIONS; ZINC; ZINC OXIDES Word Cloud More Like This Full...

  14. Direct Biological Conversion of Electrical Current into Methane by

    E-Print Network [OSTI]

    Building, The Pennsylvania State University, University Park, Pennsylvania 16802 Received December 12, 2008 to a plain carbon cathode where only small amounts of hydrogen gas could be produced. Both produced from renewable energy sources (such as wind, solar, or biomass) into a biofuel (methane) as well

  15. 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 Home Page on QA:QA J-E-1 SECTIONRobertsdale, Alabama (UtilityInstrumentsArea (DOE GTP) JumpDillard RoadEnergyOpen

  16. 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 Home Page on QA:QA J-E-1 SECTIONRobertsdale, Alabama (UtilityInstrumentsArea (DOE GTP) JumpDillard(Kauahikaua &1986)2004)Area

  17. 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 Home Page on QA:QA J-E-1 SECTIONRobertsdale, Alabama (UtilityInstrumentsArea (DOE GTP) JumpDillard(Kauahikaua

  18. 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room News PublicationsAuditsClusterInformationContractCorporateCrookerCrystalCuriosityTRANSCOM

  19. 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room News

  20. 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 Home Page on QA:QA J-E-1 SECTION JEnvironmentalBowerbank,Cammack Village,8199089°,AnalyticalCuttings Analysis