National Library of Energy BETA

Sample records for frequency variable voltage

  1. Coordination of Voltage and Frequency Feedback in Load-Frequency Control Capability of Wind Turbine

    E-Print Network [OSTI]

    Silva, Filipe Faria Da

    Coordination of Voltage and Frequency Feedback in Load-Frequency Control Capability of Wind Turbine-Frequency Control (LFC) is gradually shifted to Variable Speed Wind Turbines (VSWTs). In order to equip VSWT

  2. Variable Frequency Pump Drives 

    E-Print Network [OSTI]

    Karassik, I. J.; Petraccaro, L. L.; McGuire, J. T.

    1986-01-01

    variable flow operation, Fig. 2 variable system head, the objective of the latter being to maintain pump flow within an optimum range while accommodating a wide variation in system head. VARYING OPERATING CAPACITY OPERATING CAPACITY? N, RANGE HEAD...-rotor motors and variable speed devices have slip losses that significantly reduce the savings that accrue by operating pumps at variable speed. Steam turbine drives may not always be the most practical or economic solution. The variable frequency...

  3. Micro helical polymeric structures produced by variable voltage direct electrospinning

    E-Print Network [OSTI]

    S. P. Shariatpanahi; A. Iraji zad; I. Abdollahzadeh; R. Shirsavar; D. Bonn; R. Ejtehadi

    2011-09-12

    Direct near field electrospinning is used to produce very long helical polystyrene microfibers in water. The pitch length of helices can be controlled by changing the applied voltage, allowing to produce both micro springs and microchannels. Using a novel high frequency variable voltage electrospinning method we found the helix formation speed and compared the experimental buckling frequency to theoretical expressions for viscous and elastic buckling. Finally we showed that the newmethod can be used to produce new periodic micro and nano structures.

  4. Variable frequency photonic crystals

    E-Print Network [OSTI]

    Wu, Xiang-Yao; Liu, Xiao-Jing; Yang, Jing-Hai; Li, Hong; Chen, Wan-Jin

    2015-01-01

    In this paper, we have firstly proposed a new one-dimensional variable frequency photonic crystals (VFPCs), and calculated the transmissivity and the electronic field distribution of VFPCs with and without defect layer, and considered the effect of defect layer and variable frequency function on the transmissivity and the electronic field distribution. We have obtained some new characteristics for the VFPCs, which should be help to design a new type optical devices.

  5. Variable frequency microwave furnace system

    DOE Patents [OSTI]

    Bible, D.W.; Lauf, R.J.

    1994-06-14

    A variable frequency microwave furnace system designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity for testing or other selected applications. The variable frequency microwave furnace system includes a microwave signal generator or microwave voltage-controlled oscillator for generating a low-power microwave signal for input to the microwave furnace. A first amplifier may be provided to amplify the magnitude of the signal output from the microwave signal generator or the microwave voltage-controlled oscillator. A second amplifier is provided for processing the signal output by the first amplifier. The second amplifier outputs the microwave signal input to the furnace cavity. In the preferred embodiment, the second amplifier is a traveling-wave tube (TWT). A power supply is provided for operation of the second amplifier. A directional coupler is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter is provided for measuring the power delivered to the microwave furnace. A second power meter detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load. 5 figs.

  6. Variable frequency microwave furnace system

    DOE Patents [OSTI]

    Bible, Don W. (Clinton, TN); Lauf, Robert J. (Oak Ridge, TN)

    1994-01-01

    A variable frequency microwave furnace system (10) designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity (34) for testing or other selected applications. The variable frequency microwave furnace system (10) includes a microwave signal generator (12) or microwave voltage-controlled oscillator (14) for generating a low-power microwave signal for input to the microwave furnace. A first amplifier (18) may be provided to amplify the magnitude of the signal output from the microwave signal generator (12) or the microwave voltage-controlled oscillator (14). A second amplifier (20) is provided for processing the signal output by the first amplifier (18). The second amplifier (20) outputs the microwave signal input to the furnace cavity (34). In the preferred embodiment, the second amplifier (20) is a traveling-wave tube (TWT). A power supply (22) is provided for operation of the second amplifier (20). A directional coupler (24) is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter (30) is provided for measuring the power delivered to the microwave furnace (32). A second power meter (26) detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load (28).

  7. High frequency AC power converter for low voltage circuits

    E-Print Network [OSTI]

    Salazar, Nathaniel Jay Tobias

    2012-01-01

    This thesis presents a novel AC power delivery architecture that is suitable for VHF frequency (50-100MHz) polyphase AC/DC power conversion in low voltage integrated circuits. A complete AC power delivery architecture was ...

  8. Variable frequency microwave heating apparatus

    DOE Patents [OSTI]

    Bible, Don W. (Clinton, TN); Lauf, Robert J. (Oak Ridge, TN); Johnson, Arvid C. (Lake in the Hills, IL); Thigpen, Larry T. (Angier, NC)

    1999-01-01

    A variable frequency microwave heating apparatus (10) designed to allow modulation of the frequency of the microwaves introduced into a multi-mode microwave cavity (34) for testing or other selected applications. The variable frequency microwave heating apparatus (10) includes a microwave signal generator (12) and a high-power microwave amplifier (20) or a high-power microwave oscillator (14). A power supply (22) is provided for operation of the high-power microwave oscillator (14) or microwave amplifier (20). A directional coupler (24) is provided for detecting the direction and amplitude of signals incident upon and reflected from the microwave cavity (34). A first power meter (30) is provided for measuring the power delivered to the microwave furnace (32). A second power meter (26) detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load (28).

  9. Chapter 18: Variable Frequency Drive Evaluation Protocol

    SciTech Connect (OSTI)

    Romberger, J.

    2014-11-01

    An adjustable-speed drive (ASD) includes all devices that vary the speed of a rotating load, including those that vary the motor speed and linkage devices that allow constant motor speed while varying the load speed. The Variable Frequency Drive Evaluation Protocol presented here addresses evaluation issues for variable-frequency drives (VFDs) installed on commercial and industrial motor-driven centrifugal fans and pumps for which torque varies with speed. Constant torque load applications, such as those for positive displacement pumps, are not covered by this protocol. Other ASD devices, such as magnetic drive, eddy current drives, variable belt sheave drives, or direct current motor variable voltage drives, are also not addressed. The VFD is by far the most common type of ASD hardware. With VFD speed control on a centrifugal fan or pump motor, energy use follows the affinity laws, which state that the motor electricity demand is a cubic relationship to speed under ideal conditions. Therefore, if the motor runs at 75% speed, the motor demand will ideally be reduced to 42% of full load power; however, with other losses it is about 49% of full load power.

  10. Throughput Analysis and Voltage-Frequency Island Partitioning for Streaming Applications under Process Variation

    E-Print Network [OSTI]

    Throughput Analysis and Voltage-Frequency Island Partitioning for Streaming Applications under in video decoding) in a system with Voltage-Frequency Island (VFI) partitions in the presence of process of synchronous blocks, communicating with each other on an asynchronous basis. The concept of Voltage

  11. Dynamic Frequency and Voltage Control for a Multiple Clock Domain Microarchitecture

    E-Print Network [OSTI]

    Dwarkadas, Sandhya

    Dynamic Frequency and Voltage Control for a Multiple Clock Domain Microarchitecture Greg Semeraro the fre- quency/voltage of a Multiple Clock Domain (MCD) mi- croarchitecture. The MCD microarchitecture allows the frequency/voltage of microprocessor regions to be adjusted independently and dynamically

  12. Systems and methods for process and user driven dynamic voltage and frequency scaling

    DOE Patents [OSTI]

    Mallik, Arindam (Evanston, IL); Lin, Bin (Hillsboro, OR); Memik, Gokhan (Evanston, IL); Dinda, Peter (Evanston, IL); Dick, Robert (Evanston, IL)

    2011-03-22

    Certain embodiments of the present invention provide a method for power management including determining at least one of an operating frequency and an operating voltage for a processor and configuring the processor based on the determined at least one of the operating frequency and the operating voltage. The operating frequency is determined based at least in part on direct user input. The operating voltage is determined based at least in part on an individual profile for processor.

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

    E-Print Network [OSTI]

    Qiu, Qinru

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

  14. Aalborg Universitet Secondary Frequency and Voltage Control of Islanded Microgrids via Distributed

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    Aalborg Universitet Secondary Frequency and Voltage Control of Islanded Microgrids via Distributed., Guerrero, J. M., & Bullo, F. (2015). Secondary Frequency and Voltage Control of Islanded Microgrids via downloaded from www.microgrids.et.aau.dk is the preprint version of the final paper: J. W. Simpson-Porco, Q

  15. Adhesive bonding using variable frequency microwave energy

    DOE Patents [OSTI]

    Lauf, R.J.; McMillan, A.D.; Paulauskas, F.L.; Fathi, Z.; Wei, J.

    1998-08-25

    Methods of facilitating the adhesive bonding of various components with variable frequency microwave energy are disclosed. The time required to cure a polymeric adhesive is decreased by placing components to be bonded via the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. Methods of uniformly heating various articles having conductive fibers disposed therein are provided. Microwave energy may be selectively oriented to enter an edge portion of an article having conductive fibers therein. An edge portion of an article having conductive fibers therein may be selectively shielded from microwave energy. 26 figs.

  16. Adhesive bonding using variable frequency microwave energy

    DOE Patents [OSTI]

    Lauf, R.J.; McMillan, A.D.; Paulauskas, F.L.; Fathi, Z.; Wei, J.

    1998-09-08

    Methods of facilitating the adhesive bonding of various components with variable frequency microwave energy are disclosed. The time required to cure a polymeric adhesive is decreased by placing components to be bonded via the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. Methods of uniformly heating various articles having conductive fibers disposed therein are provided. Microwave energy may be selectively oriented to enter an edge portion of an article having conductive fibers therein. An edge portion of an article having conductive fibers therein may be selectively shielded from microwave energy. 26 figs.

  17. Adhesive bonding using variable frequency microwave energy

    DOE Patents [OSTI]

    Lauf, Robert J. (Oak Ridge, TN); McMillan, April D. (Knoxville, TN); Paulauskas, Felix L. (Oak Ridge, TN); Fathi, Zakaryae (Cary, NC); Wei, Jianghua (Raleigh, NC)

    1998-01-01

    Methods of facilitating the adhesive bonding of various components with variable frequency microwave energy are disclosed. The time required to cure a polymeric adhesive is decreased by placing components to be bonded via the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. Methods of uniformly heating various articles having conductive fibers disposed therein are provided. Microwave energy may be selectively oriented to enter an edge portion of an article having conductive fibers therein. An edge portion of an article having conductive fibers therein may be selectively shielded from microwave energy.

  18. Power System Stability Using Decentralized Under Frequency and Voltage Load Shedding

    E-Print Network [OSTI]

    Silva, Filipe Faria Da

    not be adaptive to disturbance scale. Besides, due to equality of the frequency throughout the entire power system of Frequency (ROCOF). In order to localize the LS scheme close to the disturbance place, this scheme utilizesPower System Stability Using Decentralized Under Frequency and Voltage Load Shedding Bakhtyar

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

    E-Print Network [OSTI]

    Smith, Sterling Lane

    1993-01-01

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

  20. Memory Power Management via Dynamic Voltage/Frequency Scaling

    E-Print Network [OSTI]

    Mutlu, Onur

    *Dual 4-core Intel Xeon®, 48GB DDR3 (12 DIMMs), SPEC CPU2006, all cores active. Measured AC power, analytically modeled memory power. #12;Existing Solution: Memory Sleep States? n Most memory energy for SPEC CPU2006 #12;Memory Power can be Scaled Down n DDR can operate at multiple frequencies à

  1. Low Actuation Voltage RF MEMS SwitchesWith Signal Frequencies From 0.25GHz to 40GHz

    E-Print Network [OSTI]

    Shen, Shyh-Chiang

    Low Actuation Voltage RF MEMS SwitchesWith Signal Frequencies From 0.25GHz to 40GHz Shyh-voltage radio-frequency micro- electromechanical system (RF MEMS) switch is reported. The device switching of better than 27 dB over the frequency band from 0.25GHz to 40GHz was achieved. The RF MEMS switch

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

    E-Print Network [OSTI]

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

    2014-01-01

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

  3. Voltage Stability and Frequency Synchronization of Weak Power Distribution Networks with Inverter-Based

    E-Print Network [OSTI]

    Lemmon, Michael

    a part of microgrids, are incorporated to improve power quality and reliability when disruptions happen of microgrids [13], together with oth- er generation, storage and load units. These microgrid- s are installedVoltage Stability and Frequency Synchronization of Weak Power Distribution Networks with Inverter

  4. PEV-Based Combined Frequency and Voltage Regulation for Smart Grid

    E-Print Network [OSTI]

    Mohsenian-Rad, Hamed

    by either adjusting supply or changing demand. While various demand side management programs have used benefit both users and utilities. Index Terms--Smart grid, plug-in electric vehicles, demand side management, reactive power compensation, ancillary ser- vices, frequency regulation, voltage regulation

  5. Voltage and frequency control of islanded microgrids: a plug-and-play approach

    E-Print Network [OSTI]

    Ferrari-Trecate, Giancarlo

    Voltage and frequency control of islanded microgrids: a plug-and-play approach Stefano Riverso propose a new decentralized control scheme for Islanded microGrids (ImGs) composed by the interconnection. INTRODUCTION In recent years, research on Islanded microGrids (ImG) has received major attention. ImGs are self

  6. Plug-and-play voltage and frequency control of islanded microgrids with meshed topology

    E-Print Network [OSTI]

    Ferrari-Trecate, Giancarlo

    1 Plug-and-play voltage and frequency control of islanded microgrids with meshed topology Stefano--In this paper we propose a new decentralized control scheme for Islanded microGrids (ImGs) composed proposed in IEEE standards. I. INTRODUCTION In recent years, research on Islanded microGrids (ImG) has

  7. Wind spatial variability and topographic wave frequency Elad Shilo*1

    E-Print Network [OSTI]

    Ashkenazy, Yossi "Yosef"

    Wind spatial variability and topographic wave frequency Elad Shilo*1 , Yosef Ashkenazy2 , Alon of topographic waves with wind action has been documented in several natural lakes throughout the world. However, the influence of the wind's spatial variability (wind stress curl) on the frequency of topographic waves has

  8. Present and Future Modes of Low Frequency Climate Variability

    SciTech Connect (OSTI)

    Cane, Mark A.

    2014-02-20

    This project addressed area (1) of the FOA, “Interaction of Climate Change and Low Frequency Modes of Natural Climate Variability”. Our overarching objective is to detect, describe and understand the changes in low frequency variability between model simulations of the preindustrial climate and simulations of a doubled CO2 climate. The deliverables are a set of papers providing a dynamical characterization of interannual, decadal, and multidecadal variability in coupled models with attention to the changes in this low frequency variability between pre-industrial concentrations of greenhouse gases and a doubling of atmospheric concentrations of CO2. The principle mode of analysis, singular vector decomposition, is designed to advance our physical, mechanistic understanding. This study will include external natural variability due to solar and volcanic aerosol variations as well as variability internal to the climate system. An important byproduct is a set of analysis tools for estimating global singular vector structures from the archived output of model simulations.

  9. Variable Frequency Drives: Energy Savings and Impact on Motor Performance 

    E-Print Network [OSTI]

    Petro, D.

    1993-01-01

    Variable frequency drives (VFDs) have found widespread application in recent years. VFDs are valued for their potential to save energy and improve processes. Reliability has improved significantly, but there are still pitfalls to be addressed...

  10. Control of plasma process by use of harmonic frequency components of voltage and current

    DOE Patents [OSTI]

    Miller, Paul A. (Albuquerque, NM); Kamon, Mattan (Cambridge, MA)

    1994-01-01

    The present invention provides for a technique for taking advantage of the intrinsic electrical non-linearity of processing plasmas to add additional control variables that affect process performance. The technique provides for the adjustment of the electrical coupling circuitry, as well as the electrical excitation level, in response to measurements of the reactor voltage and current and to use that capability to modify the plasma characteristics to obtain the desired performance.

  11. A Voltage Controlled Oscillator for a Phase-Locked Loop Frequency Synthesizer in a Silicon-on-Sapphire Process

    E-Print Network [OSTI]

    Garrison, Sean Michael

    2009-05-22

    and is fabricated by Peregrine Semiconductor corporation. This thesis work details the design of the Voltage Controlled Oscillator (VCO) portion of the PLL frequency synthesizer and constitutes an fully integrated VCO core circuit and a high-isolation buffer...

  12. Trapping and Frequency Variability in Electron Acoustic Waves

    E-Print Network [OSTI]

    California at San Diego, University of

    Trapping and Frequency Variability in Electron Acoustic Waves C.F. Driscoll, F. Anderegg, D 92093 USA Abstract. Electron Acoustic Waves (EAWs) with a phase velocity less than twice the plasma. Keywords: add some here PACS: 52.27.Jt, 52.35.Fp, 52.35.Sb Electron Acoustic Waves (EAWs) are the low

  13. Variable current-voltage TPV device for use in a thermophotovoltaic energy conversion system

    DOE Patents [OSTI]

    Charache, Greg W. (Clifton Park, NY); Baldasaro, Paul F. (Clifton Park, NY); Campbell, Brian C. (Scotia, NY)

    2000-01-01

    A front-side or back-side illuminated variable current-voltage thermophotovoltaic device comprises a support substrate; isolation layers disposed on the support substrate; a plurality of cells disposed on the isolation layers, each of the cells including a base layer and an emitter layer; an insulating member disposed between each of the cells configured to isolate each cell from adjacent cells; an ohmic contact configured to connect each cell to another cell in series; and a spectral control device disposed on top of the cells and/or on the bottom surface of the support substrate.

  14. Variable Frequency Operations of an Offshore Wind Power Plant with HVDC-VSC: Preprint

    SciTech Connect (OSTI)

    Gevorgian, V.; Singh, M.; Muljadi, E.

    2011-12-01

    In this paper, a constant Volt/Hz operation applied to the Type 1 wind turbine generator. Various control aspects of Type 1 generators at the plant level and at the turbine level will be investigated. Based on DOE study, wind power generation may reach 330 GW by 2030 at the level of penetration of 20% of the total energy production. From this amount of wind power, 54 GW of wind power will be generated at offshore wind power plants. The deployment of offshore wind power plants requires power transmission from the plant to the load center inland. Since this power transmission requires submarine cable, there is a need to use High-Voltage Direct Current (HVDC) transmission. Otherwise, if the power is transmitted via alternating current, the reactive power generated by the cable capacitance may cause an excessive over voltage in the middle of the transmission distance which requires unnecessary oversized cable voltage breakdown capability. The use of HVDC is usually required for transmission distance longer than 50 kilometers of submarine cables to be economical. The use of HVDC brings another advantage; it is capable of operating at variable frequency. The inland substation will be operated to 60 Hz synched with the grid, the offshore substation can be operated at variable frequency, thus allowing the wind power plant to be operated at constant Volt/Hz. In this paper, a constant Volt/Hz operation applied to the Type 1 wind turbine generator. Various control aspects of Type 1 generators at the plant level and at the turbine level will be investigated.

  15. Method for curing polymers using variable-frequency microwave heating

    DOE Patents [OSTI]

    Lauf, R.J.; Bible, D.W.; Paulauskas, F.L.

    1998-02-24

    A method for curing polymers incorporating a variable frequency microwave furnace system designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity is disclosed. By varying the frequency of the microwave signal, non-uniformities within the cavity are minimized, thereby achieving a more uniform cure throughout the workpiece. A directional coupler is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter is provided for measuring the power delivered to the microwave furnace. A second power meter detects the magnitude of reflected power. The furnace cavity may be adapted to be used to cure materials defining a continuous sheet or which require compressive forces during curing. 15 figs.

  16. Method for curing polymers using variable-frequency microwave heating

    DOE Patents [OSTI]

    Lauf, Robert J. (Oak Ridge, TN); Bible, Don W. (Clinton, TN); Paulauskas, Felix L. (Oak Ridge, TN)

    1998-01-01

    A method for curing polymers (11) incorporating a variable frequency microwave furnace system (10) designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity (34). By varying the frequency of the microwave signal, non-uniformities within the cavity (34) are minimized, thereby achieving a more uniform cure throughout the workpiece (36). A directional coupler (24) is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter (30) is provided for measuring the power delivered to the microwave furnace (32). A second power meter (26) detects the magnitude of reflected power. The furnace cavity (34) may be adapted to be used to cure materials defining a continuous sheet or which require compressive forces during curing.

  17. Detection of variable frequency signals using a fast chirp transform

    E-Print Network [OSTI]

    F. A. Jenet; T. A. Prince

    2000-12-07

    The detection of signals with varying frequency is important in many areas of physics and astrophysics. The current work was motivated by a desire to detect gravitational waves from the binary inspiral of neutron stars and black holes, a topic of significant interest for the new generation of interferometric gravitational wave detectors such as LIGO. However, this work has significant generality beyond gravitational wave signal detection. We define a Fast Chirp Transform (FCT) analogous to the Fast Fourier Transform (FFT). Use of the FCT provides a simple and powerful formalism for detection of signals with variable frequency just as Fourier transform techniques provide a formalism for the detection of signals of constant frequency. In particular, use of the FCT can alleviate the requirement of generating complicated families of filter functions typically required in the conventional matched filtering process. We briefly discuss the application of the FCT to several signal detection problems of current interest.

  18. Simulation of state-dependent high-frequency atmospheric variability associated with ENSO

    E-Print Network [OSTI]

    Kang, In-Sik

    Simulation of state-dependent high-frequency atmospheric variability associated with ENSO Jong Abstract High-frequency atmospheric variability depends on the phase of El Nino/Southern Oscillation (ENSO). Recently, there is increasing evidence that state- dependent high-frequency atmospheric variability signifi

  19. The New Active Output Filter for Variable Speed Constant Frequency Aerospace Applications 

    E-Print Network [OSTI]

    Alhuwaishel, Fahad

    2015-08-06

    capacitor filter. Moreover, the main square wave inverter has a capability to regulate the output voltage depending on the Load requirements providing a wide range of modulation index. The operation principle of the concept is demonstrated for Variable Speed...

  20. Development of high-voltage pulse-slicer unit with variable pulse duration for pulse radiolysis system

    SciTech Connect (OSTI)

    Upadhyay, J.; Sharma, M. L.; Navathe, C. P. [Laser Electronic Support Division, Raja Ramanna Centre for Advanced Technology, Indore, Madhya Pradesh 452013 (India); Toley, M. A.; Shinde, S. J.; Nadkarni, S. A.; Sarkar, S. K. [Radiation and Photochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)

    2012-02-15

    A high-voltage pulse-slicer unit with variable pulse duration has been developed and integrated with a 7 MeV linear electron accelerator (LINAC) for pulse radiolysis investigation. The pulse-slicer unit provides switching voltage from 1 kV to 10 kV with rise time better than 5 ns. Two MOSFET based 10 kV switches were configured in differential mode to get variable duration pulses. The high-voltage pulse has been applied to the deflecting plates of the LINAC for slicing of electron beam of 2 {mu}s duration. The duration of the electron beam has been varied from 30 ns to 2 {mu}s with the optimized pulse amplitude of 7 kV to get corresponding radiation doses from 6 Gy to 167 Gy.

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

    DOE Patents [OSTI]

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

    1994-01-01

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

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

    DOE Patents [OSTI]

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

    1994-06-28

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

  3. Challenges and opportunities for multi-functional oxide thin films for voltage tunable radio frequency/microwave components

    SciTech Connect (OSTI)

    Subramanyam, Guru, E-mail: gsubramanyam1@udayton.edu [Department of Electrical and Computer Engineering, University of Dayton, Dayton, Ohio 45469 (United States); Cole, M. W., E-mail: melanie.w.cole.civ@mail.mil [U.S. Army Research Laboratory, Weapons and Materials Research Directorate, Aberdeen Proving Ground, Maryland 21005 (United States); Sun, Nian X. [Department of Electrical and Computer Engineering, Northeastern University, Boston, Massachusetts 02115 (United States); Kalkur, Thottam S. [Department of Electrical and Computer Engineering, University of Colorado, Colorado Springs, Colorado 80918 (United States); Sbrockey, Nick M.; Tompa, Gary S. [Structured Materials Industries, Inc., Piscataway, New Jersey 08854 (United States); Guo, Xiaomei [Boston Applied Technologies, Inc., Woburn, Massachusetts 01801 (United States); Chen, Chonglin [Department of Physics and Astronomy, University of Texas, San Antonio, Texas 78249 (United States); Alpay, S. P.; Rossetti, G. A. [Institute of Materials Science and Materials Science and Engineering Program, University of Connecticut, Storrs, Connecticut 06269 (United States); Dayal, Kaushik [Mechanics, Materials and Computing, Civil and Environmental Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Chen, Long-Qing [Department of Materials Science and Engineering, Penn State University, University Park, Pennsylvania 16802 (United States); Schlom, Darrell G. [Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853 (United States); Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853 (United States)

    2013-11-21

    There has been significant progress on the fundamental science and technological applications of complex oxides and multiferroics. Among complex oxide thin films, barium strontium titanate (BST) has become the material of choice for room-temperature-based voltage-tunable dielectric thin films, due to its large dielectric tunability and low microwave loss at room temperature. BST thin film varactor technology based reconfigurable radio frequency (RF)/microwave components have been demonstrated with the potential to lower the size, weight, and power needs of a future generation of communication and radar systems. Low-power multiferroic devices have also been recently demonstrated. Strong magneto-electric coupling has also been demonstrated in different multiferroic heterostructures, which show giant voltage control of the ferromagnetic resonance frequency of more than two octaves. This manuscript reviews recent advances in the processing, and application development for the complex oxides and multiferroics, with the focus on voltage tunable RF/microwave components. The over-arching goal of this review is to provide a synopsis of the current state-of the-art of complex oxide and multiferroic thin film materials and devices, identify technical issues and technical challenges that need to be overcome for successful insertion of the technology for both military and commercial applications, and provide mitigation strategies to address these technical challenges.

  4. High-Frequency Resonant SEPIC Converter With Wide Input and Output Voltage Ranges

    E-Print Network [OSTI]

    Hu, Jingying

    This paper presents a resonant single-ended-primary-inductor-converter (SEPIC) converter and control method suitable for high frequency (HF) and very high frequency (VHF) dc-dc power conversion. The proposed design provides ...

  5. Adaptive, Transparent Frequency and Voltage Scaling of Communication Phases in MPI Programs

    E-Print Network [OSTI]

    Young, R. Michael

    , and an University Partnership award from IBM. Department of Computer Science, North Carolina State University are most interested in raw performance, both energy and power consumption have become critical concerns- quency and voltage scaling can produce significant energy savings with little performance penalty

  6. Verification of voltage/frequency requirement for emergency diesel generator in nuclear power plant using dynamic modeling

    SciTech Connect (OSTI)

    Hur, Jin-Suk; Roh, Myung- Sub

    2014-02-12

    One major cause of the plant shutdown is the loss of electrical power. The study is to comprehend the coping action against station blackout including emergency diesel generator, sequential loading of safety system and to ensure that the emergency diesel generator should meet requirements, especially voltage and frequency criteria using modeling tool. This paper also considered the change of the sequencing time and load capacity only for finding electrical design margin. However, the revision of load list must be verified with safety analysis. From this study, it is discovered that new load calculation is a key factor in EDG localization and in-house capability increase.

  7. Design, conditioning, and performance of a high voltage, high brightness dc photoelectron gun with variable gap

    SciTech Connect (OSTI)

    Maxson, Jared; Bazarov, Ivan; Dunham, Bruce; Dobbins, John; Liu, Xianghong; Smolenski, Karl

    2014-09-15

    A new high voltage photoemission gun has been constructed at Cornell University which features a segmented insulator and a movable anode, allowing the cathode-anode gap to be adjusted. In this work, we describe the gun's overall mechanical and high voltage design, the surface preparation of components, as well as the clean construction methods. We present high voltage conditioning data using a 50 mm cathode-anode gap, in which the conditioning voltage exceeds 500 kV, as well as at smaller gaps. Finally, we present simulated emittance results obtained from a genetic optimization scheme using voltage values based on the conditioning data. These results indicate that for charges up to 100 pC, a 30 mm gap at 400 kV has equal or smaller 100% emittance than a 50 mm gap at 450 kV, and also a smaller core emittance, when placed as the source for the Cornell energy recovery linac photoinjector with bunch length constrained to be <3 ps rms. For 100 pC up to 0.5 nC charges, the 50 mm gap has larger core emittance than the 30 mm gap, but conversely smaller 100% emittance.

  8. Low frequency variability of Southern Ocean jets Andrew F. Thompson1,2

    E-Print Network [OSTI]

    Thompson, Andrew

    Low frequency variability of Southern Ocean jets Andrew F. Thompson1,2 and Kelvin J. Richards3 is concentrated in a large number (approximately 8 to 12) of narrow filamentary jets. It is shown here that coherent jets exhibit a range of low frequency variability, on timescales of months to years, that can lead

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

    E-Print Network [OSTI]

    Rivas, Juan M.

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

  10. High-current variable-voltage rectifiers: state of the art topologies

    E-Print Network [OSTI]

    Noé, Reinhold

    , uninterruptible power supplies (UPS), inverters, wind power converters, DC power supplies and high-voltage DC Solanki1 , Norbert Fröhleke1, Joachim Böcker1, Andreas Averberg2, Peter Wallmeier2 1 Power Electronics and Electrical Drives, University of Paderborn, Paderborn, Germany 2 R&D, AEG Power Solutions GmbH, Warstein

  11. A 5GHz, 1mW CMOS Voltage Controlled Di erential Injection Locked Frequency Divider

    E-Print Network [OSTI]

    Lee, Thomas H.

    , ! is the frequency o set from !r, Vi is the incident am- plitude, H0 is the impedance of the LC tank at res- onance, Q is the quality factor of the LC tank, and a2 is the second order coe cient of the nonlinearity On chip spiral inductors with patterned ground shields 7 are used in this design. As mentioned in section

  12. A Voltage Controlled Oscillator for a Phase-Locked Loop Frequency Synthesizer in a Silicon-on-Sapphire Process

    SciTech Connect (OSTI)

    Garrison, Sean

    2009-05-21

    Engineers from a government-owned engineering and manufacturing facility were contracted by government-owned research laboratory to design and build an S-band telemetry transmitter using Radio Frequency Integrated Circuit (RFIC) technology packaged in a Low-Temperature Co-fired Ceramic (LTCC) Multi-Chip Module. The integrated circuit technology chosen for the Phase-Locked Loop Frequency Synthesizer portion of the telemetry transmitter was a 0.25 um CMOS process that utilizes a sapphire substrate and is fabricated by Peregrine Semiconductor corporation. This thesis work details the design of the Voltage Controlled Oscillator (VCO) portion of the PLL frequency synthesizer and constitutes an fully integrated VCO core circuit and a high-isolation buffer amplifier. The high-isolation buffer amplifier was designed to provide 16 dB of gain for 2200-3495 MHz as well as 60 dB of isolation for the oscillator core to provide immunity to frequency pulling due to RF load mismatch. Actual measurements of the amplifier gain and isolation showed the gain was approximately 5 dB lower than the simulated gain when all bond-wire and test substrate parasitics were taken into account. The isolation measurements were shown to be 28 dB at the high end of the frequency band but the measurement was more than likely compromised due to the aforementioned bond-wire and test substrate parasitics. The S-band oscillator discussed in this work was designed to operate over a frequency range of 2200 to 2300 MHz with a minimum output power of 0 dBm with a phase-noise of -92 dBc/Hz at a 100 kHz offset from the carrier. The tuning range was measured to be from 2215 MHz to 2330 MHz with a minimum output power of -7 dBm over the measured frequency range. A phase-noise of -90 dBc was measured at a 100 kHz offset from the carrier.

  13. Analysis and Simulation of Mechanical Trains Driven by Variable Frequency Drive Systems 

    E-Print Network [OSTI]

    Han, Xu

    2012-02-14

    Induction motors and Variable Frequency Drives (VFDs) are widely used in industry to drive machinery trains. However, some mechanical trains driven by VFD-motor systems have encountered torsional vibration problems. This vibration can induce large...

  14. High Frequency Effects of Variable Frequency Drives (VFD) on Electrical Submersible Pump (ESP) Systems 

    E-Print Network [OSTI]

    Ozkentli, Esra

    2012-10-19

    is on the system with a VFD controlled motor through a long umbilical cable. A 36-pulse VFD is studied. Since multilevel VFDs have high frequency harmonics, high frequency modeling of the umbilical cable is used, and skin effect is also taken into consideration...

  15. A study of wind variability in the lower troposphere through power spectrum analysis at mesoscale frequencies 

    E-Print Network [OSTI]

    Cornett, John Sheldon

    1966-01-01

    A STUDY OF WIND VARIABILITY IN THE LOWER TROPOSPHERE THROUGH POWER SPECTRUM ANALYSIS AT MESOSCALE FREQUENCIES A Thesis By JOHN SHELDON CORNETT Submitted to the Graduate College of the Texas A&M University in Partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE January 1966 Major Subject: Meteorology A STUDY OP WIND VARIABILITY IN THE LOWER TROPOSPHERE THROUGH POWER SPECTRUM ANALYSIS AT MESOSCALE FREQUENCIES A Thesis By JOHN SHELDON CORNETT Approved as to style...

  16. Conserving Energy in Blast Freezers Using Variable Frequency Drives 

    E-Print Network [OSTI]

    Kolbe, E.; Ling, Q.; Wheeler, G.

    2004-01-01

    ,280 cfm. This might fall by 25% in a fully loaded room. Fan motors were nominal 7-1/2 HP inverter-duty models manufactured by Baldor. Refrigeration System An engine roo m dedicated to freezing operations had a total capacity intended to meet... Baldor Model ID15H430-EO, rated for a 40 HP variable torque load. Other significant components were: - The enclosure; - A ?choke? or line reactor on the incoming line to the VFD. This serves two purposes: it protects the VFD electronics from...

  17. Continuous-Variable Quantum Computing in Optical Time-Frequency Modes using Quantum Memories

    E-Print Network [OSTI]

    Peter C. Humphreys; W. Steven Kolthammer; Joshua Nunn; Marco Barbieri; Animesh Datta; Ian A. Walmsley

    2014-11-21

    We develop a scheme for time-frequency encoded continuous-variable cluster-state quantum computing using quantum memories. In particular, we propose a method to produce, manipulate and measure 2D cluster states in a single spatial mode by exploiting the intrinsic time-frequency selectivity of Raman quantum memories. Time-frequency encoding enables the scheme to be extremely compact, requiring a number of memories that is a linear function of only the number of different frequencies in which the computational state is encoded, independent of its temporal duration. We therefore show that quantum memories can be a powerful component for scalable photonic quantum information processing architectures.

  18. Low-frequency variability of the North Pacific Ocean: The roles of boundary-and wind-driven

    E-Print Network [OSTI]

    Qiu, Bo

    Low-frequency variability of the North Pacific Ocean: The roles of boundary- and wind in determining the low-frequency large-scale variability of the ocean interior through Rossby waves generated. The variability in the ocean interior is primarily driven by wind with only a minor influence from the boundary

  19. Low-salinity pools at Barbados, West Indies: Their origin, frequency, and variability

    E-Print Network [OSTI]

    1 Low-salinity pools at Barbados, West Indies: Their origin, frequency, and variability Peter S-temperature recorders moored off the west coast of Barbados, West Indies, from May 1996 to November 1997 revealed radium 228/226 activity ratios of ~1, consistent with previous measurements in Barbados of water

  20. Observed low frequency variability of the Brazil Current front Gustavo Jorge Goni,1

    E-Print Network [OSTI]

    of the Brazil Current front. Trends of eddy kinetic energy, sea height anomaly, sea surface temperature and windObserved low frequency variability of the Brazil Current front Gustavo Jorge Goni,1 Francis Bringas; published 29 October 2011. [1] The Brazil Current is a weak western boundary current, the southwest

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

    SciTech Connect (OSTI)

    2012-01-23

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

  2. Optical voltage reference

    DOE Patents [OSTI]

    Rankin, R.; Kotter, D.

    1994-04-26

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

  3. Optical voltage reference

    DOE Patents [OSTI]

    Rankin, Richard (Ammon, ID); Kotter, Dale (Bingham County, ID)

    1994-01-01

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

  4. [A variable frequency microwave furnace]. CRADA final report for CRADA Number ORNL91-0055

    SciTech Connect (OSTI)

    Lauf, R.J.

    1994-12-08

    The goals of this CRADA were to: (1) development and demonstrate a highly frequency-agile microwave furnace; (2) explore applications of the furnace for materials processing; and (3) develop control systems and packaging that are robust, user-friendly, and suitable for sale as a turnkey system. Microwave Laboratories, Inc. (MLI) designed, built, and successfully brought to market a benchtop Variable Frequency Microwave Furnace (VFMF). The concept has demonstrated advantages in polymer curing, waste remediation, and diamond (CVD). Through experimentation and modeling, the VFMF approach has gained credibility within the technical community.

  5. Wind Spatial Variability and Topographic Wave Frequency Department of Soil and Water Sciences, Hebrew University of Jerusalem, Rehovot, Israel

    E-Print Network [OSTI]

    Ashkenazy, Yossi "Yosef"

    Wind Spatial Variability and Topographic Wave Frequency ELAD SHILO Department of Soil and Water of topographic waves with wind action has been documented in several natural lakes throughout the world. However, the influence of the wind's spatial variability (wind stress curl) on the frequency of topographic waves has

  6. T Tauri variability in the context of the beat-frequency model

    E-Print Network [OSTI]

    K. W. Smith; G. F. Lewis; I. A. Bonnell

    1995-08-17

    We examine the implications of a beat frequency modulated model of T Tauri accretion. In particular we show that measurements of the variability of accretion generated lines can be used in conjunction with existing photometry to obtain a measurement of the underlying photospheric and disc flux. This provides an independent way of checking spectral energy distribution modelling. In addition, we show how spectroscopy of T Tauri stars can reveal the inclination angle between the magnetic axis and the plane of the disc.

  7. Running time variability and resource allocation : a data-driven analysis of high-frequency bus operations

    E-Print Network [OSTI]

    Sánchez-Martínez, Gabriel Eduardo

    2013-01-01

    Running time variability is one of the most important factors determining service quality and operating cost of high-frequency bus transit. This research aims to improve performance analysis tools currently used in the bus ...

  8. Voltage Converter TYPICAL APPLICATION

    E-Print Network [OSTI]

    Berns, Hans-Gerd

    1 LTC660 100mA CMOS Voltage Converter TYPICAL APPLICATION U s Simple Conversion of 5V to ­5V Supply s Output Drive: 100mA s ROUT: 6.5 (0.65V Loss at 100mA) s BOOST Pin (Pin 1) for Higher Switching Frequency-capacitor voltage converter. It performs supply voltage conversion from positive to negative from an input range

  9. Soft switched high frequency ac-link converter 

    E-Print Network [OSTI]

    Balakrishnan, Anand Kumar

    2009-05-15

    Variable frequency drives typically have employed dc voltage or current links for power distribution between the input and output converters and as a means to temporarily store energy. The dc link based power conversion systems have several inherent...

  10. Variability-aware system-level design and analysis

    E-Print Network [OSTI]

    Chandra, Saumya

    2009-01-01

    Voltage-Frequency Island Systems,” in Proc. Int. Conf.in multi-voltage island systems) have different frequency-

  11. Comparing Two Types of Magnetically- Coupled Adjustable Speed Drives with Variable Frequency Drives in Pump and Fan Applications 

    E-Print Network [OSTI]

    Anderson, K. J.; Chvala, W. D.

    2003-01-01

    This paper presents the results from laboratory tests on MagnaDrive Corporations fixed-magnet magnetically-coupled adjustable speed drive (MC-ASD) and Coyote Electronics electromagnetic MC-ASD as compared to a typical variable frequency drive (VFD...

  12. Abstract--Time-frequency analysis of heart rate variability (HRV) makes it easier to evaluate how the balance

    E-Print Network [OSTI]

    Carvalho, João Luiz

    Abstract--Time-frequency analysis of heart rate variability (HRV) makes it easier to evaluate how-regressive model can be used to calculate the Power Spectrum Density of HRV and to create an auto of optimal orders for different interpolation rates of the HRV signal are presented. Keywords--AR model order

  13. Field Verification of Energy and Demand Savings of Two Injection Molding Machines Retrofitted with Variable Frequency Drives 

    E-Print Network [OSTI]

    Liou, S. P.; Aguiar, D.

    1999-01-01

    Detailed field measurements of energy consumption (kWh) and demand (kW) are conducted on two injection molding machines (IMMs) used in a typical plastic manufacturing facility in the San Francisco Bay Area, with/without Variable Frequency Drives...

  14. Use of Frequency Response Metrics to Assess the Planning and Operating Requirements for Reliable Integration of Variable Renewable Generation

    SciTech Connect (OSTI)

    Eto, Joseph H.; Undrill, John; Mackin, Peter; Daschmans, Ron; Williams, Ben; Haney, Brian; Hunt, Randall; Ellis, Jeff; Illian, Howard; Martinez, Carlos; O'Malley, Mark; Coughlin, Katie; LaCommare, Kristina Hamachi

    2010-12-20

    An interconnected electric power system is a complex system that must be operated within a safe frequency range in order to reliably maintain the instantaneous balance between generation and load. This is accomplished by ensuring that adequate resources are available to respond to expected and unexpected imbalances and restoring frequency to its scheduled value in order to ensure uninterrupted electric service to customers. Electrical systems must be flexible enough to reliably operate under a variety of"change" scenarios. System planners and operators must understand how other parts of the system change in response to the initial change, and need tools to manage such changes to ensure reliable operation within the scheduled frequency range. This report presents a systematic approach to identifying metrics that are useful for operating and planning a reliable system with increased amounts of variable renewable generation which builds on existing industry practices for frequency control after unexpected loss of a large amount of generation. The report introduces a set of metrics or tools for measuring the adequacy of frequency response within an interconnection. Based on the concept of the frequency nadir, these metrics take advantage of new information gathering and processing capabilities that system operators are developing for wide-area situational awareness. Primary frequency response is the leading metric that will be used by this report to assess the adequacy of primary frequency control reserves necessary to ensure reliable operation. It measures what is needed to arrest frequency decline (i.e., to establish frequency nadir) at a frequency higher than the highest set point for under-frequency load shedding within an interconnection. These metrics can be used to guide the reliable operation of an interconnection under changing circumstances.

  15. The bi-variate frequency distribution of two concurrent climatic variables: a study of temperature and dew point 

    E-Print Network [OSTI]

    Zeitler, Jon William

    1991-01-01

    Study of Temperature and Dew Point (December 1991). Jon William Zeitler, B. S. , iowa State University Chair of Advisory Comminee; Prof. John F. Griffiths The bi-variate normal distribution was fitted for the mid-season months of January, April, July... as to style and content by: Jo F. Griffnhs "' (Chair of Committee) Robert C. Runnels (Member) J. ' e (Mem r) Edward J. ser (Head of Department) December 1991 ABSTRACT The Bi-Variate Frequency Distribution of Two Concurrent Climatic Variables: A...

  16. GEOPHYSICAL RESEARCH LETTERS, VOL. 28, NO. 9, PAGES 1755-1758, MAY 1, 2001 Aliasing of high-frequency variability by altimetry

    E-Print Network [OSTI]

    Griesel, Alexa

    GEOPHYSICAL RESEARCH LETTERS, VOL. 28, NO. 9, PAGES 1755-1758, MAY 1, 2001 Aliasing of high-frequency at 10-day intervals are likely to alias substantial amounts of unresolved high-frequency vari- ability modeling studies have found sig- nificant high-frequency surface pressure variability, partic- ularly

  17. Variability-aware system-level design and analysis

    E-Print Network [OSTI]

    Chandra, Saumya

    2009-01-01

    Voltage-Frequency Island Systems,” in Proc. Int. Conf.in multi-voltage island systems) have different frequency-Frequency Island Latency-Constrained Systems,” IEEE Trans.

  18. Low Wind Speed Turbine Project Phase II: The Application of Medium-Voltage Electrical Apparatus to the Class of Variable Speed Multi-Megawatt Low Wind Speed Turbines; 15 June 2004--30 April 2005

    SciTech Connect (OSTI)

    Erdman, W.; Behnke, M.

    2005-11-01

    Kilowatt ratings of modern wind turbines have progressed rapidly from 50 kW to 1,800 kW over the past 25 years, with 3.0- to 7.5-MW turbines expected in the next 5 years. The premise of this study is simple: The rapid growth of wind turbine power ratings and the corresponding growth in turbine electrical generation systems and associated controls are quickly making low-voltage (LV) electrical design approaches cost-ineffective. This report provides design detail and compares the cost of energy (COE) between commercial LV-class wind power machines and emerging medium-voltage (MV)-class multi-megawatt wind technology. The key finding is that a 2.5% reduction in the COE can be achieved by moving from LV to MV systems. This is a conservative estimate, with a 3% to 3.5% reduction believed to be attainable once purchase orders to support a 250-turbine/year production level are placed. This evaluation considers capital costs as well as installation, maintenance, and training requirements for wind turbine maintenance personnel. Subsystems investigated include the generator, pendant cables, variable-speed converter, and padmount transformer with switchgear. Both current-source and voltage-source converter/inverter MV topologies are compared against their low-voltage, voltage-source counterparts at the 3.0-, 5.0-, and 7.5-MW levels.

  19. Method and apparatus for monitoring the rotating frequency of de-energized induction motors

    DOE Patents [OSTI]

    Mikesell, Harvey E. (McMurray, PA); Lucy, Eric (Murrysville, PA)

    1998-01-01

    The rotational speed of a coasting induction motor is measured by sensing e residual electrical voltages at the power terminals of the motor, thus eliminating the need for conventional tachometer equipment, additional mechanical components or modifications to the induction motor itself. The power terminal voltage signal is detected and transformed into a DC voltage proportional to the frequency of the signal. This DC voltage can be input to the control system of a variable frequency motor controller to regulate the output characteristics thereof relative to the speed of the coasting motor.

  20. The millimetre variability of M81* -- Multi-epoch dual frequency mm-observations of the nucleus of M81

    E-Print Network [OSTI]

    R. Schoedel; M. Krips; S. Markoff; R. Neri; A. Eckart

    2006-11-28

    There are still many open questions as to the physical mechanisms at work in Low Luminosity AGN that accrete in the extreme sub-Eddington regime. Simultaneous multi-wavelength studies have been very successful in constraining the properties of SgrA*, the extremely sub-Eddington black hole at the centre of our Milky Way. M81*, the nucleus of the nearby spiral galaxy M81, is an ideal source to extend the insights obtained on SgrA* toward higher luminosity AGN. Here we present observations at 3 and 1 mm that were obtained within the framework of a coordinated,multi-wavelength campaign on M81*. The continuum emission from M81* was observed during three epochs with the IRAM Plateau de Bure Interferometer simultaneously at wavelengths of 3 and 1 mm. We present the first flux measurements of M81* at wavelengths around 1 mm. We find that M81* is a continuously variable source with the higher variability observed at the shorter wavelength. Also, the variability at 3 and 1 mm appears to be correlated. Like SgrA*, M81* appears to display the strongest flux density and variability in the mm-to-submm regime. There remains still some ambiguity concerning the exact location of the turnover frequency from optically thick to optically thin emission. The observed variability time scales point to an upper size limit of the emitting region of the order 25 Schwarzschild radii. The data show that M81* is indeed a system with very similar physical properties to SgrA* and an ideal bridge toward high luminosity AGN. The data obtained clearly demonstrate the usefulness and, above all, the necessity of simultaneous multi-wavelength observations of LLAGN.

  1. Use of Frequency Response Metrics to Assess the Planning and Operating Requirements for Reliable Integration of Variable Renewable Generation

    E-Print Network [OSTI]

    Eto, Joseph H.

    2011-01-01

    plants to frequency response during disturbances. Use ofkey event during a disturbance when the frequency stabilizesrestore frequency to normal following a disturbance and is

  2. Temporal Variability of Waves at the Proton Cyclotron Frequency Upstream from Mars: Implications for Mars Distant Hydrogen Exosphere

    E-Print Network [OSTI]

    Bertucci, Cesar; Chaufray, Jean-Yves; Gomez, Daniel; Mazelle, Christian; Delva, Magda; Modolo, Ronan; Gonzalez-Galindo, Francisco; Brain, David Andrew

    2013-01-01

    We report on the temporal variability of the occurrence of waves at the local proton cyclotron frequency upstream from the Martian bow shock from Mars Global Surveyor observations during the first aerobraking and science phasing orbit periods. Observations at high southern latitudes during minimum-to-mean solar activity show that the wave occurrence rate is significantly higher around perihelion southern summer solstice and lower around the same hemisphere's spring and autumn equinoxes. A similar trend is observed in the hydrogen (H) exospheric density profiles over the Martian South Pole obtained from a model including UV thermospheric heating effects. In spite of the complexity in the ion pick-up and plasma wave generation and evolution processes, these results support the idea that variations in the occurrence of waves could be used to study the temporal evolution of the distant Martian H corona and its coupling with the thermosphere at altitudes currently inaccessible to direct measurements.

  3. Use of Frequency Response Metrics to Assess the Planning and Operating Requirements for Reliable Integration of Variable Renewable Generation

    E-Print Network [OSTI]

    Eto, Joseph H.

    2011-01-01

    and energy storage. Use of Frequency Response Metrics toand energy storage. xxix Use of Frequency Response Metricsfrequency control such as demand response and energy storage.

  4. Variable Frequency Drives

    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 AdministrationRobust,Field-effectWorking WithTelecentric viewingValidatingRoadmapVannevar Bush andCSV

  5. Extremum seeking-based optimization of high voltage converter modulator rise-time

    SciTech Connect (OSTI)

    Scheinker, Alexander; Bland, Michael; Krstic, Miroslav; Audia, Jeff

    2013-02-01

    We digitally implement an extremum seeking (ES) algorithm, which optimizes the rise time of the output voltage of a high voltage converter modulator (HVCM) at the Los Alamos Neutron Science Center (LANSCE) HVCM test stand by iteratively, simultaneously tuning the first 8 switching edges of each of the three phase drive waveforms (24 variables total). We achieve a 50 ?s rise time, which is reduction in half compared to the 100 ?s achieved at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory. Considering that HVCMs typically operate with an output voltage of 100 kV, with a 60Hz repetition rate, the 50 ?s rise time reduction will result in very significant energy savings. The ES algorithm will prove successful, despite the noisy measurements and cost calculations, confirming the theoretical results that the algorithm is not affected by noise whose frequency components are independent of the perturbing frequencies.

  6. Extremum seeking-based optimization of high voltage converter modulator rise-time

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

    Scheinker, Alexander; Bland, Michael; Krstic, Miroslav; Audia, Jeff

    2013-02-01

    We digitally implement an extremum seeking (ES) algorithm, which optimizes the rise time of the output voltage of a high voltage converter modulator (HVCM) at the Los Alamos Neutron Science Center (LANSCE) HVCM test stand by iteratively, simultaneously tuning the first 8 switching edges of each of the three phase drive waveforms (24 variables total). We achieve a 50 ?s rise time, which is reduction in half compared to the 100 ?s achieved at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory. Considering that HVCMs typically operate with an output voltage of 100 kV, with a 60Hz repetitionmore »rate, the 50 ?s rise time reduction will result in very significant energy savings. The ES algorithm will prove successful, despite the noisy measurements and cost calculations, confirming the theoretical results that the algorithm is not affected by noise whose frequency components are independent of the perturbing frequencies.« less

  7. Use of Frequency Response Metrics to Assess the Planning and Operating Requirements for Reliable Integration of Variable Renewable Generation

    E-Print Network [OSTI]

    Eto, Joseph H.

    2011-01-01

    wind Time (Seconds) Figure 5-3. The Power Delivered by Primary Frequency Control Actions via Generator

  8. Use of Frequency Response Metrics to Assess the Planning and Operating Requirements for Reliable Integration of Variable Renewable Generation

    E-Print Network [OSTI]

    Eto, Joseph H.

    2011-01-01

    load shedding is greater than the amount of generation that was lost, frequency will quickly rise and exceed the scheduled value.

  9. Use of Frequency Response Metrics to Assess the Planning and Operating Requirements for Reliable Integration of Variable Renewable Generation

    E-Print Network [OSTI]

    Eto, Joseph H.

    2011-01-01

    Integration of Variable Renewable Generation The report isISO (CAISO). 2007. Integration of Renewable Resources.recommendations for integrating renewable resources on the

  10. Experimental validation of a high voltage pulse measurement method.

    SciTech Connect (OSTI)

    Cular, Stefan; Patel, Nishant Bhupendra; Branch, Darren W.

    2013-09-01

    This report describes X-cut lithium niobate's (LiNbO3) utilization for voltage sensing by monitoring the acoustic wave propagation changes through LiNbO3 resulting from applied voltage. Direct current (DC), alternating current (AC) and pulsed voltage signals were applied to the crystal. Voltage induced shift in acoustic wave propagation time scaled quadratically for DC and AC voltages and linearly for pulsed voltages. The measured values ranged from 10 - 273 ps and 189 ps - 2 ns for DC and non-DC voltages, respectively. Data suggests LiNbO3 has a frequency sensitive response to voltage. If voltage source error is eliminated through physical modeling from the uncertainty budget, the sensor's U95 estimated combined uncertainty could decrease to ~0.025% for DC, AC, and pulsed voltage measurements.

  11. Wind Power Plant Voltage Stability Evaluation: Preprint

    SciTech Connect (OSTI)

    Muljadi, E.; Zhang, Y. C.

    2014-09-01

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

  12. Variable-speed wind power system with improved energy capture via multilevel conversion

    DOE Patents [OSTI]

    Erickson, Robert W.; Al-Naseem, Osama A.; Fingersh, Lee Jay

    2005-05-31

    A system and method for efficiently capturing electrical energy from a variable-speed generator are disclosed. The system includes a matrix converter using full-bridge, multilevel switch cells, in which semiconductor devices are clamped to a known constant DC voltage of a capacitor. The multilevel matrix converter is capable of generating multilevel voltage wave waveform of arbitrary magnitude and frequencies. The matrix converter can be controlled by using space vector modulation.

  13. Automatic voltage imbalance detector

    DOE Patents [OSTI]

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

    1984-01-01

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

  14. Energy-Aware Modeling and Scheduling of Real-Time Tasks for Dynamic Voltage Scaling

    E-Print Network [OSTI]

    Xu, Cheng-Zhong

    scaling (DVS) is an effective approach to power reduction by scaling the processor voltage and frequency the voltage accordingly. On the other hand, a reduction of the operating frequency leads to an increaseEnergy-Aware Modeling and Scheduling of Real-Time Tasks for Dynamic Voltage Scaling Xiliang Zhong

  15. Eliminate Voltage Unbalance

    SciTech Connect (OSTI)

    Not Available

    2000-01-01

    This two-page abstract provides tips for plant managers on checking and monitoring motor voltage unbalance to improve performance and life-span of industrial motors.

  16. Eliminate Voltage Unbalance

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

    to the voltage unbalance. Unbalanced currents lead to torque pulsations, increased vibrations and mechanical stresses, increased losses resulting in lower efficiency, and...

  17. Voltage Control Technical Conference

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

    1-08-Voltage-Control-Technical-Conference Sign In About | Careers | Contact | Investors | bpa.gov Search News & Us Expand News & Us Projects & Initiatives Expand Projects &...

  18. Collaborative Research: Process-Resolving Decomposition of the Global Temperature Response to Modes of Low Frequency Variability in a Changing Climate

    SciTech Connect (OSTI)

    Deng, Yi

    2014-11-24

    DOE-GTRC-05596 11/24/2104 Collaborative Research: Process-Resolving Decomposition of the Global Temperature Response to Modes of Low Frequency Variability in a Changing Climate PI: Dr. Yi Deng (PI) School of Earth and Atmospheric Sciences Georgia Institute of Technology 404-385-1821, yi.deng@eas.gatech.edu El Niño-Southern Oscillation (ENSO) and Annular Modes (AMs) represent respectively the most important modes of low frequency variability in the tropical and extratropical circulations. The projection of future changes in the ENSO and AM variability, however, remains highly uncertain with the state-of-the-science climate models. This project conducted a process-resolving, quantitative evaluations of the ENSO and AM variability in the modern reanalysis observations and in climate model simulations. The goal is to identify and understand the sources of uncertainty and biases in models’ representation of ENSO and AM variability. Using a feedback analysis method originally formulated by one of the collaborative PIs, we partitioned the 3D atmospheric temperature anomalies and surface temperature anomalies associated with ENSO and AM variability into components linked to 1) radiation-related thermodynamic processes such as cloud and water vapor feedbacks, 2) local dynamical processes including convection and turbulent/diffusive energy transfer and 3) non-local dynamical processes such as the horizontal energy transport in the oceans and atmosphere. In the past 4 years, the research conducted at Georgia Tech under the support of this project has led to 15 peer-reviewed publications and 9 conference/workshop presentations. Two graduate students and one postdoctoral fellow also received research training through participating the project activities. This final technical report summarizes key scientific discoveries we made and provides also a list of all publications and conference presentations resulted from research activities at Georgia Tech. The main findings include: 1) the distinctly different roles played by atmospheric dynamical processes in establishing surface temperature response to ENSO at tropics and extratropics (i.e., atmospheric dynamics disperses energy out of tropics during ENSO warm events and modulate surface temperature at mid-, high-latitudes through controlling downward longwave radiation); 2) the representations of ENSO-related temperature response in climate models fail to converge at the process-level particularly over extratropics (i.e., models produce the right temperature responses to ENSO but with wrong reasons); 3) water vapor feedback contributes substantially to the temperature anomalies found over U.S. during different phases of the Northern Annular Mode (NAM), which adds new insight to the traditional picture that cold/warm advective processes are the main drivers of local temperature responses to the NAM; 4) the overall land surface temperature biases in the latest NCAR model (CESM1) are caused by biases in surface albedo while the surface temperature biases over ocean are related to multiple factors including biases in model albedo, cloud and oceanic dynamics, and the temperature biases over different ocean basins are also induced by different process biases. These results provide a detailed guidance for process-level model turning and improvement, and thus contribute directly to the overall goal of reducing model uncertainty in projecting future changes in the Earth’s climate system, especially in the ENSO and AM variability.

  19. Voltage verification unit

    DOE Patents [OSTI]

    Martin, Edward J. (Virginia Beach, VA)

    2008-01-15

    A voltage verification unit and method for determining the absence of potentially dangerous potentials within a power supply enclosure without Mode 2 work is disclosed. With this device and method, a qualified worker, following a relatively simple protocol that involves a function test (hot, cold, hot) of the voltage verification unit before Lock Out/Tag Out and, and once the Lock Out/Tag Out is completed, testing or "trying" by simply reading a display on the voltage verification unit can be accomplished without exposure of the operator to the interior of the voltage supply enclosure. According to a preferred embodiment, the voltage verification unit includes test leads to allow diagnostics with other meters, without the necessity of accessing potentially dangerous bus bars or the like.

  20. Voltage balanced multilevel voltage source converter system

    DOE Patents [OSTI]

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

    1997-07-01

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

  1. 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.

  2. 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.

  3. Low-voltage gyrotrons

    SciTech Connect (OSTI)

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

    2013-03-15

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

  4. Device for monitoring cell voltage

    SciTech Connect (OSTI)

    Doepke, Matthias; Eisermann, Henning

    2012-08-21

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

  5. Hybrid Leakage and Voltage Reduction under EDF Scheduling Yifan Zhu Frank Mueller

    E-Print Network [OSTI]

    Mueller, Frank

    Hybrid Leakage and Voltage Reduction under EDF Scheduling Yifan Zhu Frank Mueller Department fabrication have resulted in an increasing need to conserve power of processors. While dynamic voltage scaling power. For such processors, voltage/frequency pairs below a critical speed result in higher power

  6. Energy-Aware Modeling and Scheduling for Dynamic Voltage Scaling with

    E-Print Network [OSTI]

    Xu, Cheng-Zhong

    --Dynamic voltage scaling (DVS) is a promising technique for battery-powered systems to conserve energy consumption reduction is based on dynamic voltage scaling (DVS), which exploits the super linear dependence of the power consumption of a CMOS processor on its operating voltage. However, a reduction of the operating frequency

  7. DVSleak: Combining Leakage Reduction and Voltage Scaling in Feedback EDF Scheduling

    E-Print Network [OSTI]

    Mueller, Frank

    DVSleak: Combining Leakage Reduction and Voltage Scaling in Feedback EDF Scheduling Yifan Zhu Recent trends in CMOS fabrication have the demand to conserve power of processors. While dynamic voltage fabrication processes are increasingly dominated by static power. For such processors, voltage/frequency pairs

  8. High voltage coaxial switch

    DOE Patents [OSTI]

    Rink, John P. (Los Alamos, NM)

    1983-07-19

    A coaxial high voltage, high current switch having a solid cylindrical cold cathode coaxially surrounded by a thin hollow cylindrical inner electrode and a larger hollow cylindrical outer electrode. A high voltage trigger between the cathode and the inner electrode causes electrons to be emitted from the cathode and flow to the inner electrode preferably through a vacuum. Some of the electrons penetrate the inner electrode and cause a volumetric discharge in the gas (which may be merely air) between the inner and outer electrodes. The discharge provides a low impedance path between a high voltage charge placed on the outer electrode and a load (which may be a high power laser) coupled to the inner electrode. For high repetition rate the gas between the inner and outer electrodes may be continuously exchanged or refreshed under pressure.

  9. High voltage coaxial switch

    DOE Patents [OSTI]

    Rink, J.P.

    1983-07-19

    A coaxial high voltage, high current switch having a solid cylindrical cold cathode coaxially surrounded by a thin hollow cylindrical inner electrode and a larger hollow cylindrical outer electrode. A high voltage trigger between the cathode and the inner electrode causes electrons to be emitted from the cathode and flow to the inner electrode preferably through a vacuum. Some of the electrons penetrate the inner electrode and cause a volumetric discharge in the gas (which may be merely air) between the inner and outer electrodes. The discharge provides a low impedance path between a high voltage charge placed on the outer electrode and a load (which may be a high power laser) coupled to the inner electrode. For high repetition rate the gas between the inner and outer electrodes may be continuously exchanged or refreshed under pressure. 3 figs.

  10. WECC Variable Generation Planning Reference Book: Appendices

    SciTech Connect (OSTI)

    Makarov, Yuri V.; Du, Pengwei; Etingov, Pavel V.; Ma, Jian; Vyakaranam, Bharat

    2013-05-13

    The document titled “WECC Variable Generation Planning Reference Book”. This book is divided into two volumes; one is the main document (volume 1)and the other is appendices (volume 2). The main document is a collection of the best practices and the information regarding the application and impact of variables generation on power system planning. This volume (appendices) has additional information on the following topics: Probabilistic load flow problems. 2. Additional useful indices. 3. high-impact low-frequency (HILF) events. 4. Examples of wide-area nomograms. 5. Transmission line ratings, types of dynamic rating methods. 6. Relative costs per MW-km of different electric power transmission technologies. 7. Ultra-high voltage (UHV) transmission. 8.High voltage direct current (VSC-HVDC). 9. HVDC. 10. Rewiring of existing transmission lines. 11. High-temperature low sag (HTLS) conductors. 12. The direct method and energy functions for transient stability analysis in power systems. 13.Blackouts caused by voltage instability. 14. Algorithm for parameter continuation predictor-corrector methods. 15. Approximation techniques available for security regions. 16. Impacts of wind power on power system small signals stability. 17. FIDVR. 18. FACTS. 19. European planning standard and practices. 20. International experience in wind and solar energy sources. 21. Western Renewable Energy Zones (WREZ). 22. various energy storage technologies. 23. demand response. 24. BA consolidation and cooperation options. 25. generator power management requirements and 26. European planning guidelines.

  11. E-beam high voltage switching power supply

    DOE Patents [OSTI]

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

    1996-10-15

    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.

  12. E-beam high voltage switching power supply

    DOE Patents [OSTI]

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

    1996-01-01

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

  13. High voltage pulse conditioning

    DOE Patents [OSTI]

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

    1990-01-01

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

  14. Charge-pump voltage converter

    DOE Patents [OSTI]

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

    2009-11-03

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

  15. 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.

  16. 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.

  17. increasing clock frequencies and silicon integration, power aware computing become

    E-Print Network [OSTI]

    Mudge, Trevor

    conservative supply voltage such a worst­case combination different abilities paper, we propose approach called required allowing corresponding reduction supply Since dynamic energy scales quadratically supply voltage, significant reduction energy obtained Enabling systems multiple frequency voltage is a challenging process

  18. Oscillator Architectures and Enhanced Frequency Synthesizer 

    E-Print Network [OSTI]

    Park, Sang Wook

    2009-11-16

    A voltage controlled oscillator (VCO), that generates a periodic signal whose frequency is tuned by a voltage, is a key building block in any integrated circuit systems. A sine wave oscillator can be used for a built-in self testing where high...

  19. Intermodulation electrostatic force microscopy for imaging surface photo-voltage

    SciTech Connect (OSTI)

    Borgani, Riccardo Forchheimer, Daniel; Thorén, Per-Anders; Haviland, David B.; Bergqvist, Jonas; Inganäs, Olle

    2014-10-06

    We demonstrate an alternative to Kelvin Probe Force Microscopy for imaging surface potential. The open-loop, single-pass technique applies a low-frequency AC voltage to the atomic force microscopy tip while driving the cantilever near its resonance frequency. Frequency mixing due to the nonlinear capacitance gives intermodulation products of the two drive frequencies near the cantilever resonance, where they are measured with high signal to noise ratio. Analysis of this intermodulation response allows for quantitative reconstruction of the contact potential difference. We derive the theory of the method, validate it with numerical simulation and a control experiment, and we demonstrate its utility for fast imaging of the surface photo-voltage on an organic photo-voltaic material.

  20. Very-High-Frequency Resonant Boost Converters

    E-Print Network [OSTI]

    Perreault, David J.

    This paper presents a resonant boost topology suitable for very-high-frequency (VHF, 30-300 MHz) DC-DC power conversion. The proposed design features low device voltage stress, high efficiency over a wide load range, and ...

  1. A statistical approach to designing mitigation for induced ac voltages

    SciTech Connect (OSTI)

    Dabkowski, J. [Electro Sciences, Inc., Crystal Lake, IL (United States)

    1996-08-01

    Induced voltage levels on buried pipelines collocated with overhead electric power transmission lines are usually mitigated by means of grounding the pipeline. Maximum effectiveness is obtained when grounds are placed at discrete locations along the pipeline where the peak induced voltages occur. The degree of mitigation achieved is dependent upon the local soil resistivity at these locations. On occasion it may be necessary to employ an extensive distributed grounding system, for example, a parallel buried wire connected to the pipe at periodic intervals. In this situation the a priori calculation of mitigated voltage levels is sometimes made assuming an average value for the soil resistivity. Over long distances, however, the soil resistivity generally varies as a log-normally distributed random variable. The effect of this variability upon the predicted mitigated voltage levels is examined. It is found that the predicted levels exhibit a statistical variability which precludes a precise determination of the mitigated voltage levels. Thus, post commissioning testing of the emplaced mitigation system is advisable.

  2. Temperature controlled high voltage regulator

    DOE Patents [OSTI]

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

    2004-04-20

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

  3. Voltage sensor and dielectric material

    DOE Patents [OSTI]

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

    2006-10-17

    A voltage sensor is described that consists of an arrangement of impedance elements. The sensor is optimized to provide an output ratio that is substantially immune to changes in voltage, temperature variations or aging. Also disclosed is a material with a large and stable dielectric constant. The dielectric constant can be tailored to vary with position or direction in the material.

  4. First-Principles Investigation of Nanopore Sequencing Using Variable...

    Office of Scientific and Technical Information (OSTI)

    First-Principles Investigation of Nanopore Sequencing Using Variable Voltage Bias on Graphene-Based Nanoribbons Citation Details In-Document Search Title: First-Principles...

  5. Compressional wave character in gassy, near-surface sediments in southern Louisiana determined from variable frequency cross-well, borehole logging, and surface seismic measurements

    SciTech Connect (OSTI)

    Thompson, M.D.; McGinnis, L.D.; Wilkey, P.L. [Argonne National Lab., IL (United States); Fasnacht, T. [Gas Research Inst., Chicago, IL (United States)

    1995-06-01

    Velocity and attenuation data were used to test theoretical equations describing the frequency dependence of compressional wave velocity and attenuation through gas-rich sediments in coastal Louisiana. The cross-well data were augmented with velocities derived from a nearby seismic refraction station using a low-frequency source. Energy at 1 and 3 kHz was successfully transmitted over distances from 3.69 to 30 m; the 5 and 7-kHz data were obtained only at distances up to 20 m. Velocity tomograms were constructed for one borehole pair and covered a depth interval of 10--50 m. Results from the tomographic modeling indicate that gas-induced low velocities are present to depths of greater than 40 m. Analysis of the velocity dispersion suggests that gas-bubble resonance must be greater than 7 kHz, which is above the range of frequencies used in the experiment. Washout of the boreholes at depths above 15 m resulted in a degassed zone containing velocities higher than those indicated in both nearby refraction and reflection surveys. Velocity and attenuation information were obtained for a low-velocity zone centered at a depth of approximately 18 m. Measured attenuations of 1.57, 2.95, and 3.24 dB/m for the 3-, 5-, and 7-kHz signals, respectively, were modeled along with the velocity data using a silt-clay sediment type. Density and porosity data for the model were obtained from the geophysical logs; the bulk and shear moduli were estimated from published relationships. Modeling results indicate that gas bubbles measuring 1 mm in diameter occupy at least 25% to 35% of the pore space.

  6. Clustering-Based Simultaneous Task and Voltage Scheduling for NoC Systems 

    E-Print Network [OSTI]

    Yang, Yu

    2011-08-08

    Network-on-Chip (NoC) is emerging as a promising communication structure, which is scalable with respect to chip complexity. Meanwhile, latest chip designs are increasingly leveraging multiple voltage-frequency domains for energy...

  7. E-beam high voltage switching power supply

    DOE Patents [OSTI]

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

    1997-03-11

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

  8. E-beam high voltage switching power supply

    DOE Patents [OSTI]

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

    1997-01-01

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

  9. Easily disassembled electrical connector for high voltage, high frequency connections

    DOE Patents [OSTI]

    Milner, J.R.

    1994-05-10

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

  10. Dynamic Voltage and Frequency Scaling Techniques for Chip Multiprocessor Designs 

    E-Print Network [OSTI]

    Won, Jae Yeon

    2015-08-05

    Due to chip power density limitations as well as the recent breakdown of Dennard's Scalingover the past decade, performance growth in microprocessor design has largely been driven by core scaling. These trends have led to ...

  11. Dynamic Voltage and Frequency Scaling based on Workload Decomposition*

    E-Print Network [OSTI]

    Pedram, Massoud

    monitoring unit (PMU) without a need for application profiling or compiler support. We have implemented monitoring unit (PMU), which most modern processors such as XScale80200 [1] or PXA255 [3] come equipped with

  12. Memory Power Management via Dynamic Voltage/Frequency Scaling

    E-Print Network [OSTI]

    Mutlu, Onur

    ACM 978-1-4503-0607-2/11/06 ...$10.00. its energy usage as much as its capital cost. As a result.r.hanebutte}@intel.com §Carnegie Mellon University {cfallin,onur}@cmu.edu ABSTRACT Energy efficiency and energy constraints limit system power, and datacenter operators become more conscious of energy costs, energy

  13. High voltage electrical amplifier having a short rise time

    DOE Patents [OSTI]

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

    1991-01-01

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

  14. Voltage Regulation PHYS 309 Name

    E-Print Network [OSTI]

    Herman, Rhett

    an regulated output of 5. It will also put out up to 1.5 yielding a power of 7.5. Obviously there are some LED circuits is to be used as a switch. Use 6 identical LEDs in this circuit. Use a multimeter to check that the LEDs all activate at the same voltage. Record the value of the LED voltage and your Zener

  15. A statistical approach to designing mitigation for induced AC voltages on pipelines

    SciTech Connect (OSTI)

    Dabkowski, J. [Electro Sciences Inc., Crystal Lake, IL (United States)

    1996-08-01

    Induced voltage levels on buried pipelines co-located with overhead electric power transmission lines are usually mitigated by grounding the pipeline. Maximum effectiveness is obtained when grounds are placed where the peak induced voltages occur. Mitigation depends on the local soil resistivity. It may be necessary to employ an extensive distributed grounding system. Over long distances, however, the soil resistivity generally varies as a log-normally distributed random variable. The effect of this variability is examined.

  16. Pulsed voltage electrospray ion source and method for preventing analyte electrolysis

    DOE Patents [OSTI]

    Kertesz, Vilmos (Knoxville, TN); Van Berkel, Gary (Clinton, TN)

    2011-12-27

    An electrospray ion source and method of operation includes the application of pulsed voltage to prevent electrolysis of analytes with a low electrochemical potential. The electrospray ion source can include an emitter, a counter electrode, and a power supply. The emitter can include a liquid conduit, a primary working electrode having a liquid contacting surface, and a spray tip, where the liquid conduit and the working electrode are in liquid communication. The counter electrode can be proximate to, but separated from, the spray tip. The power system can supply voltage to the working electrode in the form of a pulse wave, where the pulse wave oscillates between at least an energized voltage and a relaxation voltage. The relaxation duration of the relaxation voltage can range from 1 millisecond to 35 milliseconds. The pulse duration of the energized voltage can be less than 1 millisecond and the frequency of the pulse wave can range from 30 to 800 Hz.

  17. PREDICTING VOLTAGE DROOPS USING RECURRING PROGRAM

    E-Print Network [OSTI]

    Brooks, David

    ($200 mV for a nominal volt- age of 1.1 V).1 Such conservative operating voltage margins guarantee VOLTAGE DROOPS USING RECURRING PROGRAM AND MICROARCHITECTURAL EVENT ACTIVITY .......................................................................................................................................................................................................................... SHRINKING FEATURE SIZE AND DIMINISHING SUPPLY VOLTAGE ARE MAKING CIRCUITS MORE SENSITIVE TO SUPPLY VOLTAGE

  18. Voltage, energy and power in electric circuits

    E-Print Network [OSTI]

    Haase, Markus

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

  19. Frequency stabilization in nonlinear MEMS and NEMS oscillators

    DOE Patents [OSTI]

    Lopez, Omar Daniel; Antonio, Dario

    2014-09-16

    An illustrative system includes an amplifier operably connected to a phase shifter. The amplifier is configured to amplify a voltage from an oscillator. The phase shifter is operably connected to a driving amplitude control, wherein the phase shifter is configured to phase shift the amplified voltage and is configured to set an amplitude of the phase shifted voltage. The oscillator is operably connected to the driving amplitude control. The phase shifted voltage drives the oscillator. The oscillator is at an internal resonance condition, based at least on the amplitude of the phase shifted voltage, that stabilizes frequency oscillations in the oscillator.

  20. AN ELECTROFISHING BOAT WITH A VARIABLE VOLTAGE PULSATOR

    E-Print Network [OSTI]

    and design Equipment operation Safety precautions Literature cited . Figure l.--Boat plan Figure 2 is limited by wind conditions and the turbidity and depth of the water. It proved to be a useful tool-dwelling fishes. Mortality of fish is negligible. Cost of the unit including boat, motor, trailer, generator

  1. Variable Voltage Substation Electric Fire and Emergency Response |

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX E LIST OF APPLICABLEStatutoryin theNuclearEnergyVBA-0082 - In|955Department

  2. High voltage MOSFET switching circuit

    DOE Patents [OSTI]

    McEwan, Thomas E. (Livermore, CA)

    1994-01-01

    The problem of source lead inductance in a MOSFET switching circuit is compensated for by adding an inductor to the gate circuit. The gate circuit inductor produces an inductive spike which counters the source lead inductive drop to produce a rectangular drive voltage waveform at the internal gate-source terminals of the MOSFET.

  3. Saving Megawatts with Voltage Optimization 

    E-Print Network [OSTI]

    Wilson, T.; Bell, D.

    2010-01-01

    In September 2008, PCS UtiliData commissioned an Industrial Voltage Optimization system at the Plum Creek Timber Medium Density Fiberboard facility in Columbia Falls, Montana. The system was based upon the AdaptiVolt(TM) Volt/VAR Optimization system...

  4. Current vs. Voltage Feedback Amplifiers

    E-Print Network [OSTI]

    Papavassiliou, Christos

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

  5. High voltage MOSFET switching circuit

    DOE Patents [OSTI]

    McEwan, T.E.

    1994-07-26

    The problem of source lead inductance in a MOSFET switching circuit is compensated for by adding an inductor to the gate circuit. The gate circuit inductor produces an inductive spike which counters the source lead inductive drop to produce a rectangular drive voltage waveform at the internal gate-source terminals of the MOSFET. 2 figs.

  6. Time's Ontic Voltage Craig Callender

    E-Print Network [OSTI]

    Callender, Craig

    Time's Ontic Voltage Craig Callender Philosophy of time, as practiced throughout the last hundred venue for attacking questions about the nature of time--in sharp contrast to the primary venue slowly in philosophy of time.1 Since twentieth-century analytic philosophy as a whole often drew

  7. High frequency reference electrode

    DOE Patents [OSTI]

    Kronberg, J.W.

    1994-05-31

    A high frequency reference electrode for electrochemical experiments comprises a mercury-calomel or silver-silver chloride reference electrode with a layer of platinum around it and a layer of a chemically and electrically resistant material such as TEFLON around the platinum covering all but a small ring or halo' at the tip of the reference electrode, adjacent to the active portion of the reference electrode. The voltage output of the platinum layer, which serves as a redox electrode, and that of the reference electrode are coupled by a capacitor or a set of capacitors and the coupled output transmitted to a standard laboratory potentiostat. The platinum may be applied by thermal decomposition to the surface of the reference electrode. The electrode provides superior high-frequency response over conventional electrodes. 4 figs.

  8. High frequency reference electrode

    DOE Patents [OSTI]

    Kronberg, James W. (Aiken, SC)

    1994-01-01

    A high frequency reference electrode for electrochemical experiments comprises a mercury-calomel or silver-silver chloride reference electrode with a layer of platinum around it and a layer of a chemically and electrically resistant material such as TEFLON around the platinum covering all but a small ring or "halo" at the tip of the reference electrode, adjacent to the active portion of the reference electrode. The voltage output of the platinum layer, which serves as a redox electrode, and that of the reference electrode are coupled by a capacitor or a set of capacitors and the coupled output transmitted to a standard laboratory potentiostat. The platinum may be applied by thermal decomposition to the surface of the reference electrode. The electrode provides superior high-frequency response over conventional electrodes.

  9. High voltage photovoltaic power converter

    DOE Patents [OSTI]

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

    2001-01-01

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

  10. Power Conversion Architecture for Grid Interface at High Switching Frequency

    E-Print Network [OSTI]

    Perreault, Dave

    voltage from the voltage of energy buffer capacitor. The boost converter is often selected for PFC circuit output powers). Instead of a boost converter, one alternative for the PFC circuit is a buck converter is suitable for realizing miniaturized ac-dc converters operating at high frequencies (HF, above 3 MHz

  11. A DSP based real time power quality measurement system with voltage distortion improvement capability 

    E-Print Network [OSTI]

    Gou, Jian

    1992-01-01

    have been established to specify the limitation on the magnitudes of both harmonic currents and harmonic voltage distortion at different frequencies. Among these the "IEEE Guide for Harmonic Control and Reactive Compensation of Static Power... by the utility and by the electricity consumer has arrived. These measurements include: current and voltage harmonics, input power 1'actor, reactive power, real power, total harmonic distortion (THD), percentage load unbalance, etc. The measured data can...

  12. High-frequency matrix converter with square wave input

    DOE Patents [OSTI]

    Carr, Joseph Alexander; Balda, Juan Carlos

    2015-03-31

    A device for producing an alternating current output voltage from a high-frequency, square-wave input voltage comprising, high-frequency, square-wave input a matrix converter and a control system. The matrix converter comprises a plurality of electrical switches. The high-frequency input and the matrix converter are electrically connected to each other. The control system is connected to each switch of the matrix converter. The control system is electrically connected to the input of the matrix converter. The control system is configured to operate each electrical switch of the matrix converter converting a high-frequency, square-wave input voltage across the first input port of the matrix converter and the second input port of the matrix converter to an alternating current output voltage at the output of the matrix converter.

  13. Synchronizing carrier frequencies of co-channel amplitude-modulated broadcast

    DOE Patents [OSTI]

    Smith, Stephen F. (London, TN); Moore, James A. (Powell, TN)

    2007-05-15

    Systems and methods are described for carrier-frequency synchronization for improved AM and TV broadcast reception. A method includes synchronizing a carrier frequency of a broadcast signal with a remote reference frequency. An apparatus includes a reference signal receiver; a phase comparator coupled to the reference signal receiver; a voltage controlled oscillator coupled to the phase comparator; and a radio frequency output coupled to the voltage controlled oscillator.

  14. Carrier-frequency synchronization system for improved amplitude modulation and television broadcast reception

    DOE Patents [OSTI]

    Smith, Stephen F.; Moore, James A.

    2003-05-13

    Systems and methods are described for carrier-frequency synchronization for improved AM and TV broadcast reception. A method includes synchronizing a carrier frequency of a broadcast signal with a remote reference frequency. An apparatus includes a reference signal receiver; a phase comparator coupled to the reference signal receiver; a voltage controlled oscillator coupled to the phase comparator; and a radio frequency output coupled to the voltage controlled oscillator.

  15. Low power, scalable multichannel high voltage controller

    DOE Patents [OSTI]

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

    2006-03-14

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

  16. Low power, scalable multichannel high voltage controller

    DOE Patents [OSTI]

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

    2008-03-25

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

  17. PICSEL: Measuring User-Perceived Performance to Control Dynamic Frequency Scaling

    E-Print Network [OSTI]

    Dinda, Peter A.

    voltage and frequency scaling (DVFS) technique that uses measurements of variations in the rate of change of a computer's video output to estimate user-perceived performance. Our adaptive algorithms, one conservative and one aggressive, use these estimates to dramatically reduce operating frequencies and voltages

  18. Voltage Vehicles | 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| Open Energy Information Serbia-EnhancingEt Al.,Turin,Village of Wellington,FL LLC Jump to:EnergyVogt SolarVoltage

  19. Frequency spectrum analyzer with phase-lock

    DOE Patents [OSTI]

    Boland, Thomas J. (Idaho Falls, ID)

    1984-01-01

    A frequency-spectrum analyzer with phase-lock for analyzing the frequency and amplitude of an input signal is comprised of a voltage controlled oscillator (VCO) which is driven by a ramp generator, and a phase error detector circuit. The phase error detector circuit measures the difference in phase between the VCO and the input signal, and drives the VCO locking it in phase momentarily with the input signal. The input signal and the output of the VCO are fed into a correlator which transfers the input signal to a frequency domain, while providing an accurate absolute amplitude measurement of each frequency component of the input signal.

  20. Towards predicting voltage dependences of electrode/electrolyte...

    Office of Scientific and Technical Information (OSTI)

    voltage dependences of electrodeelectrolyte interfacial processesnin lithium ion batteries. Citation Details In-Document Search Title: Towards predicting voltage dependences...

  1. Radio frequency coaxial feedthrough

    DOE Patents [OSTI]

    Owens, Thomas L. (Kingston, TN)

    1989-01-17

    An improved radio frequency coaxial transmission line vacuum feed-through provided based on the use of a half-wavelength annular dielectric pressure barrier disk, or multiple disks comprising an effective half wavelength structure to eliminate reflections from the barrier surfaces. Gas-tight seals are formed about the outer and inner diameter surfaces of the barrier disk using a sealing technique which generates radial forces sufficient to form seals by forcing the conductor walls against the surfaces of the barrier disks in a manner which does not deform the radii of the inner and outer conductors, thereby preventing enhancement of the electric field at the barrier faces which limits voltage and power handling capabilities of a feedthrough.

  2. Strategies for Voltage Control and Transient Stability Assessment

    SciTech Connect (OSTI)

    Hiskens, Ian A.

    2013-09-25

    As wind generation grows, its influence on power system performance will becoming increasingly noticeable. Wind generation di#11;ffers from traditional forms of generation in numerous ways though, motivating the need to reconsider the usual approaches to power system assessment and performance enhancement. The project has investigated the impact of wind generation on transient stability and voltage control, identifying and addressing issues at three distinct levels of the power system: 1) at the device level, the physical characteristics of wind turbine generators (WTGs) are quite unlike those of synchronous machines, 2) at the wind-farm level, the provision of reactive support is achieved through coordination of numerous dissimilar devices, rather than straightforward generator control, and 3) from a systems perspective, the location of wind-farms on the sub-transmission network, coupled with the variability inherent in their power output, can cause complex voltage control issues. The project has sought to develop a thorough understanding of the dynamic behaviour of type-3 WTGs, and in particular the WECC generic model. The behaviour of such models is governed by interactions between the continuous dynamics of state variables and discrete events associated with limits. It was shown that these interactions can be quite complex, and may lead to switching deadlock that prevents continuation of the trajectory. Switching hysteresis was proposed for eliminating deadlock situations. Various type-3 WTG models include control blocks that duplicate integrators. It was shown that this leads to non-uniqueness in the conditions governing steady-state, and may result in pre- and post-disturbance equilibria not coinciding. It also gives rise to a zero eigenvalue in the linearized WTG model. In order to eliminate the anomalous behaviour revealed through this investigation, WECC has now released a new generic model for type-3 WTGs. Wind-farms typically incorporate a variety of voltage control equipment including tapchanging transformers, switched capacitors, SVCs, STATCOMs and the WTGs themselves. The project has considered the coordinated control of this equipment, and has addressed a range of issues that arise in wind-farm operation. The #12;first concerns the ability of WTGs to meet reactive power requirements when voltage saturation in the collector network restricts the reactive power availability of individual generators. Secondly, dynamic interactions between voltage regulating devices have been investigated. It was found that under certain realistic conditions, tap-changing transformers may exhibit instability. In order to meet cost, maintenance, fault tolerance and other requirements, it is desirable for voltage control equipment to be treated as an integrated system rather than as independent devices. The resulting high-level scheduling of wind-farm reactive support has been investigated. In addressing this control problem, several forms of future information were considered, including exact future knowledge and stochastic predictions. Deterministic and Stochastic Dynamic Programming techniques were used in the development of control algorithms. The results demonstrated that while exact future knowledge is very useful, simple prediction methods yield little bene#12;fit. The integration of inherently variable wind generation into weak grids, particularly subtransmission networks that are characterized by low X=R ratios, aff#11;ects bus voltages, regulating devices and line flows. The meshed structure of these networks adds to the complexity, especially when wind generation is distributed across multiple nodes. A range of techniques have been considered for analyzing the impact of wind variability on weak grids. Sensitivity analysis, based on the power-flow Jacobian, was used to highlight sections of a system that are most severely a#11;ffected by wind-power variations. A continuation power flow was used to determine parameter changes that reduce the impact of wind-power variability. It was also used to explore interactions betw

  3. High voltage load resistor array

    DOE Patents [OSTI]

    Lehmann, Monty Ray (Smithfield, VA)

    2005-01-18

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

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

    SciTech Connect (OSTI)

    Wohlgemuth, J.

    2013-05-01

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

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

    E-Print Network [OSTI]

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

    2000-01-01

    , Sizing Constant Voltage Transformers to Maximize Voltage Regulationfor Process Control Devices. 4. EPRl PEAC, 1997, PQTN Application Brochure #Io-Tutorial; Inrush Current Measurement 5. Basic Measuring Instruments, Inc., Alex McEachern, power...

  6. Voltage Collapse SimulationVoltage Collapse Simulation (Eastern Interconnection(Eastern Interconnection

    E-Print Network [OSTI]

    .) · Pie chart: gives percent power flow is of the line's rating 3 #12;Base Case Voltage Contours Area

  7. Electrical power inverter having a phase modulated, twin-inverter, high frequency link and an energy storage module

    DOE Patents [OSTI]

    Pitel, I.J.

    1987-02-03

    The present invention provides an electrical power inverter method and apparatus, which includes a high frequency link, for converting DC power into AC power. Generally stated, the apparatus includes a first high frequency module which produces an AC voltage at a first output frequency, and a second high frequency inverter module which produces an AC voltage at a second output frequency that is substantially the same as the first output frequency. The second AC voltage is out of phase with the first AC voltage by a selected angular phase displacement. A mixer mixes the first and second output voltages to produce a high frequency carrier which has a selected base frequency impressed on the sidebands thereof. A rectifier rectifies the carrier, and a filter filters the rectified carrier. An output inverter inverts the filtered carrier to produce an AC line voltage at the selected base frequency. A phase modulator adjusts the relative angular phase displacement between the outputs of the first and second high frequency modules to control the base frequency and magnitude of the AC line voltage. 19 figs.

  8. Electrical power inverter having a phase modulated, twin-inverter, high frequency link and an energy storage module

    DOE Patents [OSTI]

    Pitel, Ira J. (Whippany, NJ)

    1987-02-03

    The present invention provides an electrical power inverter method and apparatus, which includes a high frequency link, for converting DC power into AC power. Generally stated, the apparatus includes a first high frequency module which produces an AC voltage at a first output frequency, and a second high frequency inverter module which produces an AC voltage at a second output frequency that is substantially the same as the first output frequency. The second AC voltage is out of phase with the first AC voltage by a selected angular phase displacement. A mixer mixes the first and second output voltages to produce a high frequency carrier which has a selected base frequency impressed on the sidebands thereof. A rectifier rectifies the carrier, and a filter filters the rectified carrier. An output inverter inverts the filtered carrier to produce an AC line voltage at the selected base frequency. A phase modulator adjusts the relative angular phase displacement between the outputs of the first and second high frequency modules to control the base frequency and magnitude of the AC line voltage.

  9. Variable current speed controller for eddy current motors

    DOE Patents [OSTI]

    Gerth, H.L.; Bailey, J.M.; Casstevens, J.M.; Dixon, J.H.; Griffith, B.O.; Igou, R.E.

    1982-03-12

    A speed control system for eddy current motors is provided in which the current to the motor from a constant frequency power source is varied by comparing the actual motor speed signal with a setpoint speed signal to control the motor speed according to the selected setpoint speed. A three-phase variable voltage autotransformer is provided for controlling the voltage from a three-phase power supply. A corresponding plurality of current control resistors is provided in series with each phase of the autotransformer output connected to inputs of a three-phase motor. Each resistor is connected in parallel with a set of normally closed contacts of plurality of relays which are operated by control logic. A logic circuit compares the selected speed with the actual motor speed obtained from a digital tachometer monitoring the motor spindle speed and operated the relays to add or substract resistance equally in each phase of the motor input to vary the motor current to control the motor at the selected speed.

  10. Voltage regulation in linear induction accelerators

    DOE Patents [OSTI]

    Parsons, W.M.

    1992-12-29

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

  11. Voltage regulation in linear induction accelerators

    DOE Patents [OSTI]

    Parsons, William M. (Santa Fe, NM)

    1992-01-01

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

  12. Production of high voltage by ion bombardment 

    E-Print Network [OSTI]

    Phinney, Lucas Carter

    2003-01-01

    and was embedded in a Teflon rod. The beam energies were varied between 30 and 100 kV. A maximum voltage of approximately 90 kV was achieved on the target, and at this voltage, the power efficiency was approximately 85 percent. This power efficiency was greater...

  13. Opportunities and Challenges in Very High Frequency Power Conversion

    E-Print Network [OSTI]

    Perreault, Dave

    in switching frequency directly reduce the energy- storage requirements of power converters, improving achiev transition times. In this paper, we will focus on designs compatible with zero-voltage switching and resonant methods. We present an overview of the design of power electronics at extreme high frequencies

  14. Strongly nonlinear dynamics of electrolytes in large ac voltages Laurits Hjgaard Olesen,1,2

    E-Print Network [OSTI]

    the results have been developed for over a century 1 . Current applications include energy storage; published 2 July 2010 We study the response of a model microelectrochemical cell to a large ac voltage of frequency comparable to the inverse cell relaxation time. To bring out the basic physics, we consider

  15. Single Comparator Based A/D Converter for Output Voltage Sensing in

    E-Print Network [OSTI]

    Single Comparator Based A/D Converter for Output Voltage Sensing in Power Factor Correction frequency (2fline) without the use of a traditional analog to digital converter (A/D). The proposed method/D or a traditional A/D in a digitally controlled 300W boost PFC. I. INTRODUCTION Many implementations of digital

  16. Wide band stepped frequency ground penetrating radar

    DOE Patents [OSTI]

    Bashforth, M.B.; Gardner, D.; Patrick, D.; Lewallen, T.A.; Nammath, S.R.; Painter, K.D.; Vadnais, K.G.

    1996-03-12

    A wide band ground penetrating radar system is described embodying a method wherein a series of radio frequency signals is produced by a single radio frequency source and provided to a transmit antenna for transmission to a target and reflection therefrom to a receive antenna. A phase modulator modulates those portions of the radio frequency signals to be transmitted and the reflected modulated signal is combined in a mixer with the original radio frequency signal to produce a resultant signal which is demodulated to produce a series of direct current voltage signals, the envelope of which forms a cosine wave shaped plot which is processed by a Fast Fourier Transform Unit 44 into frequency domain data wherein the position of a preponderant frequency is indicative of distance to the target and magnitude is indicative of the signature of the target. 6 figs.

  17. Wide band stepped frequency ground penetrating radar

    DOE Patents [OSTI]

    Bashforth, Michael B. (Buellton, CA); Gardner, Duane (Santa Maria, CA); Patrick, Douglas (Santa Maria, CA); Lewallen, Tricia A. (Ventura, CA); Nammath, Sharyn R. (Santa Barbara, CA); Painter, Kelly D. (Goleta, CA); Vadnais, Kenneth G. (Alexandria, VA)

    1996-01-01

    A wide band ground penetrating radar system (10) embodying a method wherein a series of radio frequency signals (60) is produced by a single radio frequency source (16) and provided to a transmit antenna (26) for transmission to a target (54) and reflection therefrom to a receive antenna (28). A phase modulator (18) modulates those portion of the radio frequency signals (62) to be transmitted and the reflected modulated signal (62) is combined in a mixer (34) with the original radio frequency signal (60) to produce a resultant signal (53) which is demodulated to produce a series of direct current voltage signals (66) the envelope of which forms a cosine wave shaped plot (68) which is processed by a Fast Fourier Transform unit 44 into frequency domain data (70) wherein the position of a preponderant frequency is indicative of distance to the target (54) and magnitude is indicative of the signature of the target (54).

  18. Voltage controlled spintronic devices for logic applications

    DOE Patents [OSTI]

    You, Chun-Yeol (Naperville, IL); Bader, Samuel D. (Oak Park, IL)

    2001-01-01

    A reprogrammable logic gate comprising first and second voltage-controlled rotation transistors. Each transistor comprises three ferromagnetic layers with a spacer and insulating layer between the first and second ferromagnetic layers and an additional insulating layer between the second and third ferromagnetic layers. The third ferromagnetic layer of each transistor is connected to each other, and a constant external voltage source is applied to the second ferromagnetic layer of the first transistor. As input voltages are applied to the first ferromagnetic layer of each transistor, the relative directions of magnetization of the ferromagnetic layers and the magnitude of the external voltage determines the output voltage of the gate. By altering these parameters, the logic gate is capable of behaving as AND, OR, NAND, or NOR gates.

  19. Non-contact current and voltage sensor

    DOE Patents [OSTI]

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

    2014-03-25

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

  20. Flexible method for monitoring fuel cell voltage

    DOE Patents [OSTI]

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

    2002-01-01

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

  1. Energy-EfficientLow-VoltageOperation of Digital CMOS Circuits Through Charge-Recycling

    E-Print Network [OSTI]

    Shepard, Kenneth

    20.4 Energy-EfficientLow-VoltageOperation of Digital CMOS Circuits Through Charge regulator is a power transistor (shown as a variable This paper describes an energy-efficient means" to supply energy for another. When the domains are ideally balanced, all the energy dissipated by electrons

  2. Corruption of Pulsed Electric Thruster Voltage Fluctuation Measurements by Transmission Line

    E-Print Network [OSTI]

    Choueiri, Edgar

    Corruption of Pulsed Electric Thruster Voltage Fluctuation Measurements by Transmission Line to transmission line corruption--as an experimental example of the extent to which the power transmission line can termination resistance s Laplace variable V (t) transmission line driving signal Vn Laplace transform

  3. A Current-Voltage Successive Linear Programming Approach to Solving the ACOPF

    E-Print Network [OSTI]

    Oren, Shmuel S.

    , DC, USA richard.oneill@ferc.gov Variables: pg n Total linearized real power generation at bus n pg n,l Linear segment l of generation at bus n qg n Reactive power generation at bus n vn Voltage magnitude Maximum real power generation at bus n Qmin n Minimum reactive power generation at bus n Qmax n Maximum

  4. Electro-optical voltage sensor head

    DOE Patents [OSTI]

    Woods, Gregory K. (Idaho Falls, ID)

    1998-01-01

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

  5. Electro-optical voltage sensor head

    DOE Patents [OSTI]

    Woods, G.K.

    1998-03-24

    A miniature electro-optic voltage sensor system capable of accurate operation at high voltages is disclosed. The system employs a transmitter, a sensor disposed adjacent to but out of direct electrical contact with a conductor on which the voltage is to be measured, a detector, and a signal processor. The transmitter produces a beam of electromagnetic radiation which is routed into the sensor where the beam undergoes the Pockels electro-optic effect. The electro-optic effect causes phase shifting in the beam, which is in turn converted to a pair of independent beams, from which the voltage of a system based on its E-field is determined when the two beams are normalized by the signal processor. The sensor converts the beam by splitting the beam in accordance with the axes of the beam`s polarization state (an ellipse whose ellipticity varies between -1 and +1 in proportion to voltage) into at least two AM signals. These AM signals are fed into a signal processor and processed to determine the voltage between a ground conductor and the conductor on which voltage is being measured. 6 figs.

  6. Digital slip frequency generator and method for determining the desired slip frequency

    DOE Patents [OSTI]

    Klein, Frederick F. (Monroeville, PA)

    1989-01-01

    The output frequency of an electric power generator is kept constant with variable rotor speed by automatic adjustment of the excitation slip frequency. The invention features a digital slip frequency generator which provides sine and cosine waveforms from a look-up table, which are combined with real and reactive power output of the power generator.

  7. Welcome to the High Voltage Laboratory The EEH -High Voltage Laboratory is part of the Energy Transmission and High Voltage Laboratory

    E-Print Network [OSTI]

    Grabner, Helmut

    Welcome to the High Voltage Laboratory The EEH - High Voltage Laboratory is part of the Energy Transmission and High Voltage Laboratory (EEH) of the Department of Information Technology and Electrical focus of the high voltage laboratory is in the area of technologies for a future sustainable electric

  8. Low-Voltage Switched-Capacitor Circuits Emad Bidari

    E-Print Network [OSTI]

    Moon, Un-Ku

    Low-Voltage Switched-Capacitor Circuits by Emad Bidari A THESIS submitted to Oregon State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2. THE OPERATION AND IMPLEMENTATION OF THE LOW-VOLTAGE INTEGRA- TOR. LOW-VOLTAGE SC FILTER STAGES

  9. Modular high voltage power supply for chemical analysis

    DOE Patents [OSTI]

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

    2007-01-09

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

  10. Modular high voltage power supply for chemical analysis

    DOE Patents [OSTI]

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

    2008-07-15

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

  11. Modular high voltage power supply for chemical analysis

    DOE Patents [OSTI]

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

    2010-05-04

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

  12. Low voltage arc formation in railguns

    DOE Patents [OSTI]

    Hawke, Ronald S. (Livermore, CA)

    1987-01-01

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

  13. Low voltage arc formation in railguns

    DOE Patents [OSTI]

    Hawke, R.S.

    1985-08-05

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

  14. Low voltage arc formation in railguns

    DOE Patents [OSTI]

    Hawke, R.S.

    1987-11-17

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

  15. Electro-optic high voltage sensor

    DOE Patents [OSTI]

    Davidson, James R.; Seifert, Gary D.

    2003-09-16

    A small sized electro-optic voltage sensor capable of accurate measurement of high voltages without contact with a conductor or voltage source is provided. When placed in the presence of an electric field, the sensor receives an input beam of electromagnetic radiation. A polarization beam displacer separates the input beam into two beams with orthogonal linear polarizations and causes one linearly polarized beam to impinge a crystal at a desired angle independent of temperature. The Pockels effect elliptically polarizes the beam as it travels through the crystal. A reflector redirects the beam back through the crystal and the beam displacer. On the return path, the polarization beam displacer separates the elliptically polarized beam into two output beams of orthogonal linear polarization. The system may include a detector for converting the output beams into electrical signals and a signal processor for determining the voltage based on an analysis of the output beams.

  16. Voltage Management of Networks with Distributed Generation. 

    E-Print Network [OSTI]

    O'Donnell, James

    2008-01-01

    At present there is much debate about the impacts and benefits of increasing the amount of generation connected to the low voltage areas of the electricity distribution network. The UK government is under political ...

  17. Electrochemical Characterization of Voltage Fade in LMR-NMC cells...

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

    Characterization of Voltage Fade in LMR-NMC cells Electrochemical Characterization of Voltage Fade in LMR-NMC cells 2013 DOE Hydrogen and Fuel Cells Program and Vehicle...

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

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

    Voltage Fade Issue with Lithium-Manganese-Rich Oxide Cathode Materials Addressing the Voltage Fade Issue with Lithium-Manganese-Rich Oxide Cathode Materials 2012 DOE Hydrogen and...

  19. Eliminate Excessive In-Plant Distribution System Voltage Drops

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

    Undervoltage operation can result in increased currents, reduced starting torque, and lower efficiency. Suggested Actions Conduct a voltage drop survey. Voltage drop...

  20. Constant voltage electro-slag remelting control

    DOE Patents [OSTI]

    Schlienger, M.E.

    1996-10-22

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

  1. Constant voltage electro-slag remelting control

    DOE Patents [OSTI]

    Schlienger, Max E. (Albuquerque, NM)

    1996-01-01

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

  2. Group 3: Humidity, Temperature, and Voltage

    Broader source: Energy.gov [DOE]

    This PowerPoint presentation, focused on humidity, temperature and voltage testing, was originally presented by John Wohlgemuth at the NREL 2013 PV Module Reliability Workshop on Feb. 26-27, 2013 in Denver, CO. It summarizes the activities of a working group chartered to develop accelerated stress tests that can be used as comparative predictors of module life versus stresses associated with humidity, temperature and voltage.

  3. High-frequency electric field measurement using a toroidal antenna

    DOE Patents [OSTI]

    Lee, Ki Ha (Lafayette, CA)

    2002-01-01

    A simple and compact method and apparatus for detecting high frequency electric fields, particularly in the frequency range of 1 MHz to 100 MHz, uses a compact toroidal antenna. For typical geophysical applications the sensor will be used to detect electric fields for a wide range of spectrum starting from about 1 MHz, in particular in the frequency range between 1 to 100 MHz, to detect small objects in the upper few meters of the ground. Time-varying magnetic fields associated with time-varying electric fields induce an emf (voltage) in a toroidal coil. The electric field at the center of (and perpendicular to the plane of) the toroid is shown to be linearly related to this induced voltage. By measuring the voltage across a toroidal coil one can easily and accurately determine the electric field.

  4. High-frequency irradiance fluctuations and geographic smoothing

    E-Print Network [OSTI]

    Lave, Matthew; Kleissl, Jan; Arias-Castro, Ery

    2012-01-01

    of the variability of irradiance and PV power time series1997. Study of areal solar irradiance for analyzing areally-High-frequency irradiance fluctuations and geographic

  5. Development of a quantum-voltage-calibrated noise thermometer at NIM

    SciTech Connect (OSTI)

    Qu, J.; Zhang, J. T.; Fu, Y.; Rogalla, H.; Pollarolo, A.; Benz, S. P.

    2013-09-11

    A quantum-voltage-calibrated Johnson-noise thermometer was developed at NIM, which measures the Boltzmann constant k by comparing the thermal noise across a 100 ? sense resistor at the temperature of the triple point of water with the pseudo-random frequency-comb voltage waveform synthesized with a bipolar-pulse-driven quantum-voltage-noise source. A measurement with integration period of 10 hours and bandwidth of 640 kHz resulted in a relative offset of 0.5×10{sup ?6} from the current CODATA value of k, and a type A relative standard uncertainty of 23×10{sup ?6}. Benefiting from closely matched noise powers and transmission-line impedances and small nonlinearities in the cross-correlation electronics, the derived k shows self-consistent values and standard uncertainties for different measurement bandwidths.

  6. Interconnected High-Voltage Pulsed-Power Converters System Design for H? Ion Sources

    E-Print Network [OSTI]

    Aguglia, D

    2014-01-01

    This paper presents the design and experimental validations of a system of three new high-voltage (HV) pulsedpower converters for the H? sources. The system requires three pulsed voltages (50, 40, and 25 kV to ground) at 2-Hz repetition rate, for 700 ?s of usable flat-top. The solution presents ripplefree output voltages and minimal stored energy to protect the ion source from the consequences of arc events. Experimental results on the final full-scale prototype are presented. In case of short-circuit events, the maximal energy delivered to the source is in the Joule range. HV flat-top stability of 1% is experimentally achieved with a simple Proportional-Integral- Derivative regulation and preliminary tuned H? source (e.g., radio frequency control, gas injection, and so forth). The system is running since more than a year with no power converter failures and damage to the source.

  7. An accurate continuous calibration system for high voltage current transformer

    SciTech Connect (OSTI)

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

    2011-02-15

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

  8. Low Voltage Operational Amplifier Design for Energy Harvesting Applications

    E-Print Network [OSTI]

    Collins, Gary S.

    Low Voltage Operational Amplifier Design for Energy Harvesting Applications Brisa Calderon, Dr provide low voltages, all the components in a PMS must be able to operate at low voltages. Optimizing these components to operate at low voltages in turn contributes to the optimization of the PMS as a whole. Theory

  9. System for transmitting low frequency analog signals over AC power lines

    DOE Patents [OSTI]

    Baker, Steven P. (Powell, TN); Durall, Robert L. (Lenoir City, TN); Haynes, Howard D. (Knoxville, TN)

    1989-01-01

    A system for transmitting low frequency analog signals over AC power lines using FM modulation. A low frequency analog signal to be transmitted is first applied to a voltage-to-frequency converter where it is converted to a signal whose frequency varies in proportion to the analog signal amplitude. This signal is then used to modulate the carrier frequency of an FM transmitter coupled to an AC power line. The modulation signal frequency range in selected to be within the response band of the FM transmitter. The FM modulated carrier signal is received by an FM receiver coupled to the AC power line, demodulated and the demodulated signal frequency is converted by a frequency-to-voltage converter back to the form of the original low frequency analog input signal.

  10. A system for tranmitting low frequency analog signals over ac power lines

    DOE Patents [OSTI]

    Baker, S.P.; Durall, R.L.; Haynes, H.D.

    1987-07-30

    A system for transmitting low frequency analog signals over ac power lines using FM modulation. A low frequency analog signal to be transmitted is first applied to a voltage-to-frequency converter where it is converted to a signal whose frequency varies in proportion to the analog signal amplitude. This signal is then used to modulate the carrier frequency of an FM transmitter coupled to an ac power line. The modulation signal frequency range is selected to be within the response band of the FM transmitter. The FM modulated carrier signal is received by an FM receiver coupled to the ac power line, demodulated and the demodulated signal frequency is converted by a frequency-to-voltage converter back to the form of the original low frequency analog input signal. 4 figs.

  11. Soft-Switching High-Frequency AC-Link Universal Power Converters with Galvanic Isolation 

    E-Print Network [OSTI]

    Amirabadi, Mahshid

    2013-08-07

    be used in a variety of applications, including photovoltaic power generation, wind power generation, and electric vehicles. In these converters the link current and voltage are both alternating and their frequency can be high, which leads...

  12. Principles of ground relaying for high voltage and extra high voltage transmission lines

    SciTech Connect (OSTI)

    Griffin, C.H.

    1983-02-01

    This paper is a tutorial discussion of the basic principles of ground relaying for high voltage and extra high voltage transmission lines. Three different HV configurations are considered: Long lines, lines with a weak mid-point station, and mutually-coupled lines. Application criteria for EHV circuits are also discussed, and specific setting calculations are included where appropriate.

  13. Electronic circuit for measuring series connected electrochemical cell voltages

    DOE Patents [OSTI]

    Ashtiani, Cyrus N. (West Bloomfield, MI); Stuart, Thomas A. (Toledo, OH)

    2000-01-01

    An electronic circuit for measuring voltage signals in an energy storage device is disclosed. The electronic circuit includes a plurality of energy storage cells forming the energy storage device. A voltage divider circuit is connected to at least one of the energy storage cells. A current regulating circuit is provided for regulating the current through the voltage divider circuit. A voltage measurement node is associated with the voltage divider circuit for producing a voltage signal which is proportional to the voltage across the energy storage cell.

  14. Characterization of arcs in frequency domain

    SciTech Connect (OSTI)

    D'Inca, R.; Siegl, G.; Faugel, H.; Braun, F.; Eckert, B.; Bobkov, V.; El Khaldi, M.; Noterdaeme, J.-M.

    2009-11-26

    Arc detection systems are developed for ICRH on ITER to prevent arcs from damaging the RF components. One of the detectors, the Sub-Harmonic Arc Detector (SHAD) is based on the detection of the frequencies emitted in the MHz range by arcs [R1]. To ensure the high level of reliability required for this safety system, it is necessary to demonstrate that these frequencies present a signal with a Signal to Noise Ratio high enough to be detected under the wide range of operational conditions (frequency, power, configuration) and for the different types of arcs that can appear in the feeding lines and on the antennas (vacuum arc, glow discharge, multipactor-induced discharge). For each type of arc, we analyze the evolution of the frequency spectrum relative to the evolution of other electrical parameters (reflected power, voltage)

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

    DOE Patents [OSTI]

    Woods, G.K.; Renak, T.W.

    1999-04-06

    A miniature electro-optic voltage sensor system capable of accurate operation at high voltages is disclosed. The system employs a transmitter, a sensor disposed adjacent to but out of direct electrical contact with a conductor on which the voltage is to be measured, a detector, and a signal processor. The transmitter produces a beam of electromagnetic radiation which is routed into the sensor where the beam undergoes the Pockels electro-optic effect. The electro-optic effect causes phase shifting in the beam, which is in turn converted to a pair of independent beams, from which the voltage of a system based on its E-field is determined when the two beams are normalized by the signal processor. The sensor converts the beam by splitting the beam in accordance with the axes of the beam`s polarization state (an ellipse whose ellipticity varies between -1 and +1 in proportion to voltage) into at least two AM signals. These AM signals are fed into a signal processor and processed to determine the voltage between a ground conductor and the conductor on which voltage is being measured. 18 figs.

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

    DOE Patents [OSTI]

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

    1999-01-01

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

  17. Variable Speed Pumping for Level Control 

    E-Print Network [OSTI]

    Vasel, M.

    1982-01-01

    analysis, and a brief discussion of variable frequency drive design considerations. Energy savings figures are based upon actual electricity costs at the plant involved. Process duty cycle and energy requirement levels were verified by a wattmeter...

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

    SciTech Connect (OSTI)

    Wohlgemuth, J.

    2013-09-01

    This is a summary of the work of Group 3 of the International PV QA Task Force. Group 3 is chartered to develop accelerated stress tests that can be used as comparative predictors of module lifetime versus stresses associated with humidity, temperature and voltage.

  19. Voltage control on a train system

    DOE Patents [OSTI]

    Gordon, Susanna P.; Evans, John A.

    2004-01-20

    The present invention provides methods for preventing low train voltages and managing interference, thereby improving the efficiency, reliability, and passenger comfort associated with commuter trains. An algorithm implementing neural network technology is used to predict low voltages before they occur. Once voltages are predicted, then multiple trains can be controlled to prevent low voltage events. Further, algorithms for managing inference are presented in the present invention. Different types of interference problems are addressed in the present invention such as "Interference During Acceleration", "Interference Near Station Stops", and "Interference During Delay Recovery." Managing such interference avoids unnecessary brake/acceleration cycles during acceleration, immediately before station stops, and after substantial delays. Algorithms are demonstrated to avoid oscillatory brake/acceleration cycles due to interference and to smooth the trajectories of closely following trains. This is achieved by maintaining sufficient following distances to avoid unnecessary braking/accelerating. These methods generate smooth train trajectories, making for a more comfortable ride, and improve train motor reliability by avoiding unnecessary mode-changes between propulsion and braking. These algorithms can also have a favorable impact on traction power system requirements and energy consumption.

  20. Preventing Delayed Voltage Recovery with Voltage-Regulating Distributed Energy Resources

    SciTech Connect (OSTI)

    Adhikari, Sarina; Li, Fangxing; Li, Huijuan; Xu, Yan; Kueck, John D; Rizy, D Tom

    2009-01-01

    With the large use of residential air conditioner (A/C) motors during the summer peaks, the potential of motor stalling events have increased in the recent years. The stalled motor loads have been found to be the most important cause of delayed voltage recovery following severe system disturbances, such as a subtransmission fault. The proper modeling of the stalled motors is a very important factor in identifying the effect of these motors in voltage recovery after the fault. This paper presents a methodology for modeling the stalled low inertia induction motors based on a sample utility system and a small primary distribution circuit. The prevention of the stalling of motors plays an important role in maintaining the voltage profile of the system after system disturbances. Distributed Energy Resource (DER) is used to prevent the motor stalling events so that the delayed voltage recovery of the system may be avoided.

  1. Method of detecting system function by measuring frequency response

    DOE Patents [OSTI]

    Morrison, John L. (Butte, MT); Morrison, William H. (Manchester, CT); Christophersen, Jon P. (Idaho Falls, ID)

    2012-04-03

    Real-time battery impedance spectrum is acquired using a one-time record. Fast Summation Transformation (FST) is a parallel method of acquiring a real-time battery impedance spectrum using a one-time record that enables battery diagnostics. An excitation current to a battery is a sum of equal amplitude sine waves of frequencies that are octave harmonics spread over a range of interest. A sample frequency is also octave and harmonically related to all frequencies in the sum. The time profile of this signal has a duration that is a few periods of the lowest frequency. The voltage response of the battery, average deleted, is the impedance of the battery in the time domain. Since the excitation frequencies are known and octave and harmonically related, a simple algorithm, FST, processes the time record by rectifying relative to the sine and cosine of each frequency. Another algorithm yields real and imaginary components for each frequency.

  2. Cataclysmic Variables

    E-Print Network [OSTI]

    Robert Connon Smith

    2007-01-23

    Cataclysmic variables are binary stars in which a relatively normal star is transferring mass to its compact companion. This interaction gives rise to a rich range of behaviour, of which the most noticeable are the outbursts that give the class its name. Novae belong to the class, as do the less well known dwarf novae and magnetic systems. Novae draw their energy from nuclear reactions, while dwarf novae rely on gravity to power their smaller eruptions. All the different classes of cataclysmic variable can be accommodated within a single framework and this article will describe the framework, review the properties of the main types of system and discuss models of the outbursts and of the long-term evolution.

  3. Low voltage amplifier architecture for high speed switched capacitor circuits 

    E-Print Network [OSTI]

    Shankar, Asit

    2001-01-01

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

  4. Electrical system architecture having high voltage bus

    DOE Patents [OSTI]

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

    2011-03-22

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

  5. Low Voltage White Phosphorescent OLED Achievements

    Broader source: Energy.gov [DOE]

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

  6. Long term voltage stability analysis for small disturbances 

    E-Print Network [OSTI]

    Men, Kun

    2009-05-15

    design and optimize the system. ?? Challenge 2, accurately estimating voltage stability margin online remains as a dream for industry. So far, due to heavy computation burden, the major thrust in voltage stability analysis, especially for large... of load dynamics to restore power consumption beyond the capability of the combined transmission and generation system. ? This definition try to emphasize that load is the main driving force of a voltage collapse, and voltage stability is a stuctural...

  7. Field Optimization of Three Dimensional High Voltage C. Trinitis

    E-Print Network [OSTI]

    Stamatakis, Alexandros

    The design of high voltage systems and their com­ ponents (e.g. gas insulated switchgear, trans­ formers etc

  8. Electro-optic voltage sensor head

    DOE Patents [OSTI]

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

    1999-08-17

    The invention is an electro-optic voltage sensor head designed for integration with existing types of high voltage transmission and distribution apparatus. The sensor head contains a transducer, which comprises a transducing material in which the Pockels electro-optic effect is observed. In the practice of the invention at least one beam of electromagnetic radiation is routed into the transducing material of the transducer in the sensor head. The beam undergoes an electro-optic effect in the sensor head when the transducing material is subjected to an E-field. The electro-optic effect is observed as a differential phase a shift, also called differential phase modulation, of the beam components in orthogonal planes of the electromagnetic radiation. In the preferred embodiment the beam is routed through the transducer along an initial axis and then reflected by a retro-reflector back substantially parallel to the initial axis, making a double pass through the transducer for increased measurement sensitivity. The preferred embodiment of the sensor head also includes a polarization state rotator and at least one beam splitter for orienting the beam along major and minor axes and for splitting the beam components into two signals which are independent converse amplitude-modulated signals carrying E-field magnitude and hence voltage information from the sensor head by way of optic fibers. 6 figs.

  9. Electrostatically screened, voltage-controlled electrostatic chuck

    DOE Patents [OSTI]

    Klebanoff, Leonard Elliott (San Ramon, CA)

    2001-01-01

    Employing an electrostatically screened, voltage-controlled electrostatic chuck particularly suited for holding wafers and masks in sub-atmospheric operations will significantly reduce the likelihood of contaminant deposition on the substrates. The electrostatic chuck includes (1) an insulator block having a outer perimeter and a planar surface adapted to support the substrate and comprising at least one electrode (typically a pair of electrodes that are embedded in the insulator block), (2) a source of voltage that is connected to the at least one electrode, (3) a support base to which the insulator block is attached, and (4) a primary electrostatic shield ring member that is positioned around the outer perimeter of the insulator block. The electrostatic chuck permits control of the voltage of the lithographic substrate; in addition, it provides electrostatic shielding of the stray electric fields issuing from the sides of the electrostatic chuck. The shielding effectively prevents electric fields from wrapping around to the upper or front surface of the substrate, thereby eliminating electrostatic particle deposition.

  10. Aalborg Universitet Current-voltage model of LED light sources

    E-Print Network [OSTI]

    Munk-Nielsen, Stig

    Aalborg Universitet Current-voltage model of LED light sources Beczkowski, Szymon; Munk version (APA): Beczkowski, S., & Munk-Nielsen, S. (2012). Current-voltage model of LED light sources from vbn.aau.dk on: juli 06, 2015 #12;Current-voltage model of LED light sources Szymon Bczkowski, Stig

  11. LOW VOLTAGE ANALOG CIRCUITS USING STANDARD CMOS TECHNOLOGY

    E-Print Network [OSTI]

    Rincon-Mora, Gabriel A.

    LOW VOLTAGE ANALOG CIRCUITS USING STANDARD CMOS TECHNOLOGY Phillip E. Allen, Benjamin J. Blalock implies battery operation which favors low voltage and low power circuits. These factors and others have of the magnitudes of the n-channel and p-channel thresholds [4]. This implies that low voltage analog circuits

  12. System for increasing corona inception voltage of insulating oils

    DOE Patents [OSTI]

    Rohwein, G.J.

    1998-05-19

    The Corona Inception Voltage of insulating oils is increased by repetitive cycles of prestressing the oil with a voltage greater than the corona inception voltage, and either simultaneously or serially removing byproducts of corona by evacuation and heating the oil. 5 figs.

  13. Electrical Circuit Flashover Model of Polluted Insulators under AC Voltage Based on the Arc Root Voltage Gradient Criterion

    E-Print Network [OSTI]

    Yang, Qing

    In order to study the flashover mechanism of polluted insulators under AC voltage, a new arc propagation criterion which is based on an arc root voltage gradient is proposed. This criterion can explain the variation of the ...

  14. IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, VOL. 55, NO. 4, APRIL 2007 1193 Frequency Tunable Microstrip Patch Antenna Using RF

    E-Print Network [OSTI]

    Akin, Tayfun

    integrated with RF microelectromechanical systems (MEMS) capacitors for tuning the resonant frequency at low dc voltages. Index Terms--Microelectromechanical system (MEMS), microstrip an- tennas, microwave, reconfigurable architectures. I. INTRODUCTION Microelectromechanical systems (MEMS) and the application

  15. Energy-aware Workflow Scheduling Using Frequency Scaling Ilia Pietri, Rizos Sakellariou

    E-Print Network [OSTI]

    Sakellariou, Rizos

    when overall energy consumption can be decreased. Synthetic data based on parameters of real scientific overall energy consumption. Keywords-energy-aware scheduling; frequency scaling; DVFS; DAG scheduling to a respective voltage level [3]. Lowering the frequency may lead to decreased energy consumption

  16. Voltage measurements at the vacuum post-hole convolute of the Z pulsed-power accelerator

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

    Waisman, E. M.; McBride, R. D.; Cuneo, M. E.; Wenger, D. F.; Fowler, W. E.; Johnson, W. A.; Basilio, L. I.; Coats, R. S.; Jennings, C. A.; Sinars, D. B.; et al

    2014-12-08

    Presented are voltage measurements taken near the load region on the Z pulsed-power accelerator using an inductive voltage monitor (IVM). Specifically, the IVM was connected to, and thus monitored the voltage at, the bottom level of the accelerator’s vacuum double post-hole convolute. Additional voltage and current measurements were taken at the accelerator’s vacuum-insulator stack (at a radius of 1.6 m) by using standard D-dot and B-dot probes, respectively. During postprocessing, the measurements taken at the stack were translated to the location of the IVM measurements by using a lossless propagation model of the Z accelerator’s magnetically insulated transmission lines (MITLs)more »and a lumped inductor model of the vacuum post-hole convolute. Across a wide variety of experiments conducted on the Z accelerator, the voltage histories obtained from the IVM and the lossless propagation technique agree well in overall shape and magnitude. However, large-amplitude, high-frequency oscillations are more pronounced in the IVM records. It is unclear whether these larger oscillations represent true voltage oscillations at the convolute or if they are due to noise pickup and/or transit-time effects and other resonant modes in the IVM. Results using a transit-time-correction technique and Fourier analysis support the latter. Regardless of which interpretation is correct, both true voltage oscillations and the excitement of resonant modes could be the result of transient electrical breakdowns in the post-hole convolute, though more information is required to determine definitively if such breakdowns occurred. Despite the larger oscillations in the IVM records, the general agreement found between the lossless propagation results and the results of the IVM shows that large voltages are transmitted efficiently through the MITLs on Z. These results are complementary to previous studies [R. D. McBride et al., Phys. Rev. ST Accel. Beams 13, 120401 (2010)] that showed efficient transmission of large currents through the MITLs on Z. Altogether, the two studies demonstrate the overall efficient delivery of very large electrical powers through the MITLs on Z.« less

  17. Voltage measurements at the vacuum post-hole convolute of the ? pulsed-power accelerator

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

    Waisman, E.? M.; McBride, R. D.; Cuneo, M.? E.; Wenger, D.? F.; Fowler, W.? E.; Johnson, W.? A.; Basilio, L.? I.; Coats, R.? S.; Jennings, C.? A.; Sinars, D.? B.; et al

    2014-11-08

    Presented are voltage measurements taken near the load region on the Z pulsed-power accelerator using an inductive voltage monitor (IVM). Specifically, the IVM was connected to, and thus monitored the voltage at, the bottom level of the accelerator’s vacuum double post-hole convolute. Additional voltage and current measurements were taken at the accelerator’s vacuum-insulator stack (at a radius of 1.6 m) by using standard D-dot and B-dot probes, respectively. During postprocessing, the measurements taken at the stack were translated to the location of the IVM measurements by using a lossless propagation model of the Z accelerator’s magnetically insulated transmission lines (MITLs)more »and a lumped inductor model of the vacuum post-hole convolute. Across a wide variety of experiments conducted on the Z accelerator, the voltage histories obtained from the IVM and the lossless propagation technique agree well in overall shape and magnitude. However, large-amplitude, high-frequency oscillations are more pronounced in the IVM records. It is unclear whether these larger oscillations represent true voltage oscillations at the convolute or if they are due to noise pickup and/or transit-time effects and other resonant modes in the IVM. Results using a transit-time-correction technique and Fourier analysis support the latter. Regardless of which interpretation is correct, both true voltage oscillations and the excitement of resonant modes could be the result of transient electrical breakdowns in the post-hole convolute, though more information is required to determine definitively if such breakdowns occurred. Despite the larger oscillations in the IVM records, the general agreement found between the lossless propagation results and the results of the IVM shows that large voltages are transmitted efficiently through the MITLs on Z. These results are complementary to previous studies [R.D. McBride et al., Phys. Rev. ST Accel. Beams 13, 120401 (2010)] that showed efficient transmission of large currents through the MITLs on Z. Taken together, the two studies demonstrate the overall efficient delivery of very large electrical powers through the MITLs on Z.« less

  18. Voltage measurements at the vacuum post-hole convolute of the Z pulsed-power accelerator

    SciTech Connect (OSTI)

    Waisman, E. M.; McBride, R. D.; Cuneo, M. E.; Wenger, D. F.; Fowler, W. E.; Johnson, W. A.; Basilio, L. I.; Coats, R. S.; Jennings, C. A.; Sinars, D. B.; Vesey, R. A.; Jones, B.; Ampleford, D. J.; Lemke, R. W.; Martin, M. R.; Schrafel, P. C.; Lewis, S. A.; Moore, J. K.; Savage, M. E.; Stygar, W. A.

    2014-12-08

    Presented are voltage measurements taken near the load region on the Z pulsed-power accelerator using an inductive voltage monitor (IVM). Specifically, the IVM was connected to, and thus monitored the voltage at, the bottom level of the accelerator’s vacuum double post-hole convolute. Additional voltage and current measurements were taken at the accelerator’s vacuum-insulator stack (at a radius of 1.6 m) by using standard D-dot and B-dot probes, respectively. During postprocessing, the measurements taken at the stack were translated to the location of the IVM measurements by using a lossless propagation model of the Z accelerator’s magnetically insulated transmission lines (MITLs) and a lumped inductor model of the vacuum post-hole convolute. Across a wide variety of experiments conducted on the Z accelerator, the voltage histories obtained from the IVM and the lossless propagation technique agree well in overall shape and magnitude. However, large-amplitude, high-frequency oscillations are more pronounced in the IVM records. It is unclear whether these larger oscillations represent true voltage oscillations at the convolute or if they are due to noise pickup and/or transit-time effects and other resonant modes in the IVM. Results using a transit-time-correction technique and Fourier analysis support the latter. Regardless of which interpretation is correct, both true voltage oscillations and the excitement of resonant modes could be the result of transient electrical breakdowns in the post-hole convolute, though more information is required to determine definitively if such breakdowns occurred. Despite the larger oscillations in the IVM records, the general agreement found between the lossless propagation results and the results of the IVM shows that large voltages are transmitted efficiently through the MITLs on Z. These results are complementary to previous studies [R. D. McBride et al., Phys. Rev. ST Accel. Beams 13, 120401 (2010)] that showed efficient transmission of large currents through the MITLs on Z. Altogether, the two studies demonstrate the overall efficient delivery of very large electrical powers through the MITLs on Z.

  19. Extremely high frequency RF effects on electronics.

    SciTech Connect (OSTI)

    Loubriel, Guillermo Manuel; Vigliano, David; Coleman, Phillip Dale; Williams, Jeffery Thomas; Wouters, Gregg A.; Bacon, Larry Donald; Mar, Alan

    2012-01-01

    The objective of this work was to understand the fundamental physics of extremely high frequency RF effects on electronics. To accomplish this objective, we produced models, conducted simulations, and performed measurements to identify the mechanisms of effects as frequency increases into the millimeter-wave regime. Our purpose was to answer the questions, 'What are the tradeoffs between coupling, transmission losses, and device responses as frequency increases?', and, 'How high in frequency do effects on electronic systems continue to occur?' Using full wave electromagnetics codes and a transmission-line/circuit code, we investigated how extremely high-frequency RF propagates on wires and printed circuit board traces. We investigated both field-to-wire coupling and direct illumination of printed circuit boards to determine the significant mechanisms for inducing currents at device terminals. We measured coupling to wires and attenuation along wires for comparison to the simulations, looking at plane-wave coupling as it launches modes onto single and multiconductor structures. We simulated the response of discrete and integrated circuit semiconductor devices to those high-frequency currents and voltages, using SGFramework, the open-source General-purpose Semiconductor Simulator (gss), and Sandia's Charon semiconductor device physics codes. This report documents our findings.

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

    E-Print Network [OSTI]

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

    2014-10-15

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

  1. Coupling effects in inductive discharges with radio frequency substrate biasing

    SciTech Connect (OSTI)

    Schulze, J.; Schuengel, E.; Czarnetzki, U.

    2012-01-09

    Low pressure inductively coupled plasmas (ICP) operated in neon at 27.12 MHz with capacitive substrate biasing (CCP) at 13.56 MHz are investigated by phase resolved optical emission spectroscopy, voltage, and current measurements. Three coupling mechanisms are found potentially limiting the separate control of ion energy and flux: (i) Sheath heating due to the substrate biasing affects the electron dynamics even at high ratios of ICP to CCP power. At fixed CCP power, (ii) the substrate sheath voltage and (iii) the amplitude as well as frequency of plasma series resonance oscillations of the RF current are affected by the ICP power.

  2. Low-frequency interaction between horizontal and overturning gyres in the ocean

    E-Print Network [OSTI]

    Low-frequency interaction between horizontal and overturning gyres in the ocean M. A. Spall1] Low-frequency variability of the horizontal circulation in an idealized, eddy-permitting, numerical model drives the dominant mode of low-frequency variability in the meridional overturning circulation

  3. Apparatus for producing voltage and current pulses

    DOE Patents [OSTI]

    Kirbie, Hugh (Los Alamos, NM); Dale, Gregory E. (Los Alamos, NM)

    2010-12-21

    An apparatus having one or more modular stages for producing voltage and current pulses. Each module includes a diode charging means to charge a capacitive means that stores energy. One or more charging impedance means are connected to the diode charging means to provide a return current pathway. A solid-state switch discharge means, with current interruption capability, is connected to the capacitive means to discharge stored energy. Finally, a control means is provided to command the switching action of the solid-state switch discharge means.

  4. Eliminate Voltage Unbalance | 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 GasAdjustmentsShirleyEnergyTher i n cEnergy (AZ,Local GovernmentofVoltage unbalance degrades the performance

  5. Large voltage-induced modification of spin-orbit torques in Pt/Co/GdOx

    SciTech Connect (OSTI)

    Emori, Satoru Bauer, Uwe; Woo, Seonghoon; Beach, Geoffrey S. D.

    2014-12-01

    We report on large modifications of current-induced spin-orbit torques in a gated Pt/Co/Gd-oxide microstrip due to voltage-driven O{sup 2?} migration. The Slonczewski-like and field-like torques are quantified using a low-frequency harmonic technique based on the polar magneto-optical Kerr effect. Voltage-induced oxidation of Co enhances the Slonczewski-like torque by as much as an order of magnitude and simultaneously reduces the anisotropy energy barrier by a factor of ?5. Such magneto-ionic tuning of interfacial spin-orbit effects may significantly enhance the efficiency of magnetization switching and provide additional degrees of freedom in spintronic devices.

  6. Variable nonlinear resistances 

    E-Print Network [OSTI]

    Howard, James Edgar

    1955-01-01

    are shown 1n Figure 3. For a constant gr1d voltage 12 the lines are straight except at, low voltages. Fig. pent o(ie curves generally follow the curves shown in Figure 4 when plotted on linear scales. -x5 Fig. 4 13 'w'hen plotted on lop vs lop paper...

  7. Safe epoxy encapsulant for high voltage magnetics

    SciTech Connect (OSTI)

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

    1998-01-01

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

  8. Low Switching Frequency Active Harmonic Elimination in Multilevel Converters with Unequal DC Voltages

    E-Print Network [OSTI]

    Tolbert, Leon M.

    The multilevel converter is a promising technology for renewable/distributed energy applications of power electronics because of its easy connection with renewable/distributed energy modules such as fuel cells, solar panels, and wind turbines. Other benefits also include its low electromagnetic interference (EMI

  9. Off-chip Latency-Driven Dynamic Voltage and Frequency Scaling for an MPEG Decoding

    E-Print Network [OSTI]

    Pedram, Massoud

    time. The on- chip workload for an incoming frame is predicted using a frame- based history so (to thus maximize the battery service time) without any appreciable degradation in the QoS. DVFS. An archetypal example of such a task is MPEG decoding in which the computational workload fluctuates greatly

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

    E-Print Network [OSTI]

    Ellingson, Steven W.

    , the Bureau of Land Management (BLM) hired Vernon L. Chartier of the Bonneville Power Administration (BPA above 30 MHz is the method developed by the Bonneville Power Administration (Chartier 1983). The BPA in Appendix A. As described by Pakala and Chartier (1971) power lines are divided into two classes

  11. Fine-Grained Dynamic Voltage and Frequency Scaling for Precise Energy and Performance

    E-Print Network [OSTI]

    Pedram, Massoud

    Monitoring Unit (PMU) ! Proposed Fine-grained DVFS Policy ! Experimental Results ! Conclusion #12;2 Energy Monitoring Unit (PMU) ! PMU on the XScale processor chip can report up to 20 different dynamic events during be monitored and reported at any given time ! For DVFS, we use PMU to generate statistics for " Total no

  12. Dynamic Voltage and Frequency Scaling Under a Precise Energy Model Considering

    E-Print Network [OSTI]

    Pedram, Massoud

    is accessed Performance monitoring unit (PMU) ! Won is modeled as: ! PMU on the PXA255 processor chip can ! For DVFS, we use the PMU to generate statistics for " Total no. of instructions being executed (INSTR) " No

  13. Off-chip Latency-Driven Dynamic Voltage and Frequency Scaling for

    E-Print Network [OSTI]

    Pedram, Massoud

    ;5 Performance Monitoring Unit (PMU)Performance Monitoring Unit (PMU) ! PMU on the XScale can provide values

  14. Voltage and Frequency Stability of Weak Power Distribution Networks with Droop-Controlled

    E-Print Network [OSTI]

    Lemmon, Michael

    generations (DG's), based on both synchronous generators (SG's) and fast inverters, are incorporated ratio (SCR) in [2]. Connections of DG's, based on both fast inverters and synchronous generators (SG-Controlled Rotational and Electronic Distributed Generators Zhao Wang1 and Michael Lemmon1 Abstract Distributed

  15. Design of low-voltage, high-bandwidth radio frequency power converters

    E-Print Network [OSTI]

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

    2012-01-01

    The mass and volume required for power electronics circuitry is a dominant obstacle to the miniaturization and integration of many systems. Likewise, power electronics with greater bandwidth and efficiency are becoming ...

  16. A Near State PWM Method With Reduced Switching Frequency And Reduced Common Mode Voltage

    E-Print Network [OSTI]

    Hava, Ahmet

    operation in AC-DC power converter applications, and supply high quality power in uninterruptible power supply AC-DC-AC power converter units. Pulse Width Modulation (PWM) is the standard approach to operate

  17. Micro-grid operation of inverter based distributed generation with voltage and frequency dependent loads

    E-Print Network [OSTI]

    Zeineldin, H. H.

    Distribution systems are experiencing increasing penetration of distributed generation (DG). One attractive option is to use the available DG capacity during utility outages by forming planned micro-grids. Load sharing ...

  18. Dynamic Voltage and Frequency Scaling Control for Crossbars in Input-Queued Switches

    E-Print Network [OSTI]

    . Hence, reducing the power consumption is an important design question to improve the crossbar switching Abstract--The power consumption in chips, in general, and in crossbars switching fabrics, in particular for the switching fabrics implemented on chip. Indeed, the power consumption increases more than linearly

  19. Planar LTCC transformers for high voltage flyback converters.

    SciTech Connect (OSTI)

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

    2007-06-01

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

  20. Sequential circuit design for radiation hardened multiple voltage integrated circuits

    DOE Patents [OSTI]

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

    2009-11-24

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

  1. Method for voltage-gated protein fractionation

    DOE Patents [OSTI]

    Hatch, Anson (Tracy, CA); Singh, Anup K. (Danville, CA)

    2012-04-24

    We report unique findings on the voltage dependence of protein exclusion from the pores of nanoporous polymer exclusion membranes. The pores are small enough that proteins are excluded from passage with low applied electric fields, but increasing the field enables proteins to pass through. The requisite field necessary for a change in exclusion is protein-specific with a correlation to protein size. The field-dependence of exclusion is important to consider for preconcentration applications. The ability to selectively gate proteins at exclusion membranes is also a promising means for manipulating and characterizing proteins. We show that field-gated exclusion can be used to selectively remove proteins from a mixture, or to selectively trap protein at one exclusion membrane in a series.

  2. Conservation Theory Process Control Using Variable Frequency Drives 

    E-Print Network [OSTI]

    Myers, N. S.

    1980-01-01

    stream_source_info ESL-IE-80-04-104.pdf.txt stream_content_type text/plain stream_size 12263 Content-Encoding ISO-8859-1 stream_name ESL-IE-80-04-104.pdf.txt Content-Type text/plain; charset=ISO-8859-1 CONSERVATION... staffs of most companies to evaluate the energy consumption and effi ciency of new and existing facilities. Some of the energy conserving equipment which seemed too costly or complex a few short years ago are now becoming the engineer's strongest...

  3. Variable Frequency AC Drives for Cooling Tower Energy Efficiency 

    E-Print Network [OSTI]

    Corey, R. W.

    1982-01-01

    speed and AF drive conversion to adjustable speed. ~I.,.. '~'Fixed r--'T'~Speed ,_0t.11T ~ ! AUTO ~uAL Figure 3 - Fixed &~djustable Speed sJstems I The AF control .unit is placed in the user's motor control center or inl a weather protected..., this ov~r simplified analysis does put this project in a very likely position for budget approval by the Texas Company p~ant management. 5.0 SUMMARY Traditionally, capita~ expense for eqUipment has been submitted for management approval...

  4. Variable Frequency Motor Drives: Harmonics, Power Factor, and Energy Efficiency 

    E-Print Network [OSTI]

    Massey, G. W.

    1997-01-01

    harmonics and power factor. NOTE: The views expressed in this paper do not necessarily represent the views of the United States of America, the U.S. Department of Justice, or the Federal Bureau of Prisons....

  5. Low-profile high-voltage compact gas switch

    SciTech Connect (OSTI)

    Goerz, D.A.; Wilson, M.J.; Speer, R.D.

    1997-06-30

    This paper discusses the development and testing of a low-profile, high-voltage, spark-gap switch designed to be closely coupled with other components into an integrated high-energy pulsed-power source. The switch is designed to operate at 100 kV using SF6 gas pressurized to less than 0.7 MPa. The volume of the switch cavity region is less than 1.5 cm3, and the field stress along the gas-dielectric interface is as high as 130 kV/cm. The dielectric switch body has a low profile that is only I -cm tall at its greatest extent and nominally 2-mm thick over most of its area. This design achieves a very low inductance of less than 5 nH, but results in field stresses exceeding 500 kV/cm in the dielectric material. Field modeling was done to determine the appropriate shape for the highly stressed insulator and electrodes, and special manufacturing techniques were employed to mitigate the usual mechanisms that induce breakdown and failure in solid dielectrics. Static breakdown tests verified that the switch operates satisfactorily at 100 kV levels. The unit has been characterized with different shaped electrodes having nominal gap spacings of 2.0, 2.5, and 3.0 mm. The relationship between self-break voltage and operating pressure agrees well with published data on gas properties, accounting for the field enhancements of the electrode shapes being used. Capacitor discharge tests in a low inductance test fixture exhibited peak currents up to 25 kA with characteristic frequencies of the ringdown circuit ranging from 10 to 20 MHz. The ringdown waveforms and scaling of measured parameters agree well with circuit modeling of the switch and test fixture. Repetitive operation has been demonstrated at moderate rep-rates up to 15 Hz, limited by the power supply being used. Preliminary tests to evaluate lifetime of the compact switch assembly have been encouraging. In one case, after more than 7,000 high-current ringdown tests with approximately 30 C of total charge transferred, the switch continued to operate satisfactorily with no apparent tracking or deterioration of the insulator.

  6. Voltage-controlled entanglement and quantum-information transfer...

    Office of Scientific and Technical Information (OSTI)

    external gate voltage in our schemes. Moreover, proposed schemes are robust against the noise of system parameters. Authors: Lue Xinyou ; Zheng Lili 1 ; Wu, Jing 2 ; Zhan...

  7. Fault-induced delayed voltage recovery in a long inhomogeneous...

    Office of Scientific and Technical Information (OSTI)

    Article: Fault-induced delayed voltage recovery in a long inhomogeneous power-distribution feeder Citation Details In-Document Search This content will become publicly...

  8. A multilevel voltage-source inverter with separate dc sources...

    Office of Scientific and Technical Information (OSTI)

    conditioning, series compensation, phase shifting, voltage balancing, fuel cell and photovoltaic utility systems interfacing, etc. The new M-level inverter consists of (M-1)2...

  9. 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.

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

    Energy Savers [EERE]

    the Voltage Fade Issue with Lithium-Manganese-Rich Oxide Cathode Materials 2013 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer...

  11. Towards First Principles prediction of Voltage Dependences of...

    Office of Scientific and Technical Information (OSTI)

    Voltage Dependences of ElectrolyteElectrolyte Interfacial Processes in Lithium Ion Batteries. Citation Details In-Document Search Title: Towards First Principles prediction of...

  12. Sharp interface and voltage conservation in the phase field method

    E-Print Network [OSTI]

    2007-07-14

    of rabbit ventricles, with a corresponding reduction in simulation time. ... applied to cardiac tissue modeling and examine voltage conservation when using this.

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

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

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

  14. Nanoscale Morphological and Chemical Changes of High Voltage...

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

    Nanoscale Morphological and Chemical Changes of High Voltage Lithium-Manganese Rich NMC Composite Cathodes with Cycling Friday, August 29, 2014 Renewable energy is critical for the...

  15. Frequency comb swept lasers

    E-Print Network [OSTI]

    Tsai, Tsung-Han

    We demonstrate a frequency comb (FC) swept laser and a frequency comb Fourier domain mode locked (FC-FDML) laser for applications in optical coherence tomography (OCT). The fiber-based FC swept lasers operate at a sweep ...

  16. Eastern Frequency Response Study

    SciTech Connect (OSTI)

    Miller, N.W.; Shao, M.; Pajic, S.; D'Aquila, R.

    2013-05-01

    This study was specifically designed to investigate the frequency response of the Eastern Interconnection that results from large loss-of-generation events of the type targeted by the North American Electric Reliability Corp. Standard BAL-003 Frequency Response and Frequency Bias Setting (NERC 2012a), under possible future system conditions with high levels of wind generation.

  17. Method for sputtering with low frequency alternating current

    DOE Patents [OSTI]

    Timberlake, John R. (Allentown, NJ)

    1996-01-01

    Low frequency alternating current sputtering is provided by connecting a low frequency alternating current source to a high voltage transformer having outer taps and a center tap for stepping up the voltage of the alternating current. The center tap of the transformer is connected to a vacuum vessel containing argon or helium gas. Target electrodes, in close proximity to each other, and containing material with which the substrates will be coated, are connected to the outer taps of the transformer. With an applied potential, the gas will ionize and sputtering from the target electrodes onto the substrate will then result. The target electrodes can be copper or boron, and the substrate can be stainless steel, aluminum, or titanium. Copper coatings produced are used in place of nickel and/or copper striking.

  18. UPGRADING THE CEBAF INJECTOR WITH A NEW BOOSTER, HIGHER VOLTAGE GUN, AND HIGHER FINAL ENERGY

    SciTech Connect (OSTI)

    Reza Kazimi, Arne Freyberger, Alicia Hofler, Andrew Hutton, Fay Hannon

    2012-07-01

    The Continuous Electron Beam Accelerator Facility (CEBAF) accelerator at Jefferson Lab will be upgraded from 6 GeV to 12 GeV in the next few years. To meet the requirement of the new machine and to take the opportunity to improve the beam quality, the CEBAF injector will be upgraded with a higher voltage gun, a new booster, and a new accelerating RF module. The CEBAF injector creates and accelerates three beams at different currents simultaneously. The beams are interleaved, each at one third of the RF frequency, traveling through the same beam line. The higher voltage gun will lower the space charge effects. The new booster with optimized beam dynamics will complete the bunching process and provide initial acceleration matched to the new gun voltage. Using our latest SRF design, the new booster has significantly lower x/y coupling effects that should improve our beam setup and operation for the highly sensitive parity experiments scheduled for the CEBAF's future. Finally, the new accelerating RF module will roughly double the injector final energy to match the rest of the 12 GeV accelerator. In this paper we will provide more detail about this upgrade.

  19. 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.

  20. Nonparametric estimation of econometric models with categorical variables 

    E-Print Network [OSTI]

    Ouyang, Desheng

    2006-10-30

    shows that regression model with only discrete vari- ables differs significantly from the mixed discrete and continuous variables case. In the mixed variable case with at least one relevant continuous regressor, the irrele- vant variables can be smoothed... CV-based estimator has a high probability of smoothing out the irrele- vant variable, hence it leads to a more efficient (in finite samples) estimation result than the frequency estimator. It is interesting to observe that our nonparametric CV...

  1. Radio frequency detection assembly and method for detecting radio frequencies

    DOE Patents [OSTI]

    Cown, Steven H. (Rigby, ID); Derr, Kurt Warren (Idaho Falls, ID)

    2010-03-16

    A radio frequency detection assembly is described and which includes a radio frequency detector which detects a radio frequency emission produced by a radio frequency emitter from a given location which is remote relative to the radio frequency detector; a location assembly electrically coupled with the radio frequency detector and which is operable to estimate the location of the radio frequency emitter from the radio frequency emission which has been received; and a radio frequency transmitter electrically coupled with the radio frequency detector and the location assembly, and which transmits a radio frequency signal which reports the presence of the radio frequency emitter.

  2. Stability issues in IC Low Drop Out voltage regulators 

    E-Print Network [OSTI]

    Chava, Krishna Chaitanya

    2002-01-01

    . The problem of instability of the LDO voltage regulator at low Electo Static Resistance (ESR) of the load capacitors and the consequences of this problem are highlighted. As a solution to some of the discussed problems, an alternate LDO voltage regulator...

  3. CLNS 03/1827 VERY HIGH VOLTAGE PHOTOEMISSION ELECTRON GUNS*

    E-Print Network [OSTI]

    CLNS 03/1827 VERY HIGH VOLTAGE PHOTOEMISSION ELECTRON GUNS* Charles K. Sinclair # , Cornell voltage DC electron guns with photoemission cathodes are a natural choice for generating the beams gradient in these guns. The photocathode operational lifetime is limited by the gun vacuum and by ion back

  4. Aalborg Universitet Secondary Control for Voltage Quality Enhancement in Microgrids

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    Aalborg Universitet Secondary Control for Voltage Quality Enhancement in Microgrids Savaghebi). Secondary Control for Voltage Quality Enhancement in Microgrids. I E E E Transactions on Smart Grid, 3 in Microgrids," Smart Grid, IEEE Transactions on , vol.3, no.4, pp.1893-1902, Dec. 2012. doi: 10.1109/TSG.2012

  5. Measurement of high voltage using Rutherford backscattering spectrometry 

    E-Print Network [OSTI]

    Abrego, Celestino Pete

    2007-04-25

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

  6. Multi-winding Homopolar Electric Machine Offers Variable Voltage at Low

    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 wouldMass map shines light on77 PAGEMissionStressMove dataKiel7 Site Map Printable

  7. Appears in the Proceedings of the 47th Int'l Symp. on Microarchitecture (MICRO-47), December 2014 Enabling Realistic Fine-Grain Voltage Scaling with

    E-Print Network [OSTI]

    Batten, Christopher

    of high-speed switching with suitable parasitic losses; and (2) limited availability of integrated energy-storage- tion complexity, power density, power efficiency, and response time. In this paper, we use architecture-level modeling to explore a new dynamic voltage/frequency scaling controller called the fine

  8. Generation of a frequency comb and applications thereof

    DOE Patents [OSTI]

    Hagmann, Mark J; Yarotski, Dmitry A

    2013-12-03

    Apparatus for generating a microwave frequency comb (MFC) in the DC tunneling current of a scanning tunneling microscope (STM) by fast optical rectification, cause by nonlinearity of the DC current vs. voltage curve for the tunneling junction, of regularly-spaced, short pulses of optical radiation from a focused mode-locked, ultrafast laser, directed onto the tunneling junction, is described. Application of the MFC to high resolution dopant profiling in semiconductors is simulated. Application of the MFC to other measurements is described.

  9. The design of a frequency modulated transistor oscillator 

    E-Print Network [OSTI]

    Fisher, Phil Dewey

    1959-01-01

    . Special thanks are extended to the Texas Power and. Light Companp for their financial assistance during the course of this investigation. CONTENTS TABLE OF FIGURES. TABLE OF SYMBOLS. INTRODUCTION. OSCILLATOR DESIGN. Page . vii . . . 1 Seleotion... Oscillator. . . 21 Figure 11. Frequency Deviation vs. Temperature for the Uncompensated Oscillator. , 28 Figure 12. Results of the Emitter-Thermistor Compensation. . 31 Figure 13. Thermistor-Diode Compensation Circuit. . . . ~ ~ 32 Figure 14. Voltage...

  10. Radio frequency sheaths in an oblique magnetic field

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

    Myra, James R.; D'Ippolito, Daniel A.

    2015-06-01

    The physics of radio-frequency (rf) sheaths near a conducting surface is studied for plasmas immersed in a magnetic field that makes an oblique angle ? with the surface. A set of one-dimensional equations is developed that describe the dynamics of the time-dependent magnetic presheath and non-neutral Debye sheath. The model employs Maxwell-Boltzmann electrons, and the magnetization and mobility of the ions is determined by the magnetic field strength, and wave frequency, respectively. The angle, ? assumed to be large enough to insure an electron-poor sheath, is otherwise arbitrary. Concentrating on the ion-cyclotron range of frequencies, the equations are solved numericallymore »to obtain the rectified (dc) voltage, the rf voltage across the sheath and the rf current flowing through the sheath. As an application of this model, the sheath voltage-current relation is used to obtain the rf sheath impedance, which in turn gives an rf sheath boundary condition for the electric field at the sheath-plasma interface that can be used in rf wave codes. In general the impedance has both resistive and capacitive contributions, and generalizes previous sheath boundary condition models. The resistive part contributes to parasitic power dissipation at the wall.« less

  11. Understanding Inertial and Frequency Response of Wind Power Plants: Preprint

    SciTech Connect (OSTI)

    Muljadi, E.; Gevorgian, V.; Singh, M.; Santoso, S.

    2012-07-01

    The objective of this paper is to analyze and quantify the inertia and frequency responses of wind power plants with different wind turbine technologies (particularly those of fixed speed, variable slip with rotor-resistance controls, and variable speed with vector controls).

  12. Bonfire-safe low-voltage detonator

    DOE Patents [OSTI]

    Lieberman, Morton L. (Albuquerque, NM)

    1990-01-01

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

  13. Bonfire-safe low-voltage detonator

    DOE Patents [OSTI]

    Lieberman, M.L.

    1988-07-01

    A column of explosive in a low-voltage detonator which makes it bonfire-safe includes a first layer of an explosive charge of CP, or a primary explosive, and a second layer of a secondary organic explosive charge, such as PETN, which has a degradation temperature lower than the autoignition temperature of the CP or primary explosives. The first layer is composed of a pair of increments disposed in a bore of a housing of the detonator in an ignition region of the explosive column and adjacent to and in contact with an electrical ignition device at one end of the bore. The second layer is composed of a plurality of increments disposed in the housing bore in a transition region of the explosive column next to and in contact with the first layer on a side opposite from the ignition device. The first layer is loaded under a sufficient high pressure, 25 to 40 kpsi, to achieve ignition, whereas the second layer is loaded under a sufficient low pressure, about 10 kpsi, to allow occurrence of DDT. Each increment of the first and second layers has an axial length-to-diameter ratio of one-half. 2 figs.

  14. Spark-safe low-voltage detonator

    DOE Patents [OSTI]

    Lieberman, Morton L. (Albuquerque, NM)

    1989-01-01

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

  15. Dynamic frequency tuning of electric and magnetic metamaterial response

    DOE Patents [OSTI]

    O'Hara, John F; Averitt, Richard; Padilla, Willie; Chen, Hou-Tong

    2014-09-16

    A geometrically modifiable resonator is comprised of a resonator disposed on a substrate, and a means for geometrically modifying the resonator. The geometrically modifiable resonator can achieve active optical and/or electronic control of the frequency response in metamaterials and/or frequency selective surfaces, potentially with sub-picosecond response times. Additionally, the methods taught here can be applied to discrete geometrically modifiable circuit components such as inductors and capacitors. Principally, controlled conductivity regions, using either reversible photodoping or voltage induced depletion activation, are used to modify the geometries of circuit components, thus allowing frequency tuning of resonators without otherwise affecting the bulk substrate electrical properties. The concept is valid over any frequency range in which metamaterials are designed to operate.

  16. Beat Frequency Modulation of T Tauri Accretion Rates

    E-Print Network [OSTI]

    K. W. Smith; I. A. Bonnell; G. F. Lewis

    1995-04-10

    A general model of magnetically controlled accretion onto T Tauri stars is presented. In this model the magnetic field is oriented arbitrarily in relation to the star's rotation axis. The resultant interplay between the magnetic field and accretion disc causes a variable accretion rate. The dominant timescale of this variability is the beat frequency between the stellar rotation frequency and the orbital frequency at the magnetosphere boundary. This model is analogous to that developed to explain quasi-periodic oscillations in low-mass X-ray binaries.

  17. Frequency Response Analysis Tool

    SciTech Connect (OSTI)

    Etingov, Pavel V.; Kosterev, Dmitry; Dai, T.

    2014-12-31

    Frequency response has received a lot of attention in recent years at the national level, which culminated in the development and approval of North American Electricity Reliability Corporation (NERC) BAL-003-1 Frequency Response and Frequency Bias Setting Reliability Standard. This report is prepared to describe the details of the work conducted by Pacific Northwest National Laboratory (PNNL) in collaboration with the Bonneville Power Administration and Western Electricity Coordinating Council (WECC) Joint Synchronized Information Subcommittee (JSIS) to develop a frequency response analysis tool (FRAT). The document provides the details on the methodology and main features of the FRAT. The tool manages the database of under-frequency events and calculates the frequency response baseline. Frequency response calculations are consistent with frequency response measure (FRM) in NERC BAL-003-1 for an interconnection and balancing authority. The FRAT can use both phasor measurement unit (PMU) data, where available, and supervisory control and data acquisition (SCADA) data. The tool is also capable of automatically generating NERC Frequency Response Survey (FRS) forms required by BAL-003-1 Standard.

  18. Electro-optic voltage sensor with beam splitting

    DOE Patents [OSTI]

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

    2002-01-01

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

  19. Electro-optic voltage sensor with Multiple Beam Splitting

    DOE Patents [OSTI]

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

    2000-01-01

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

  20. Analyzing and simulating the variability of solar irradiance and solar PV powerplants

    E-Print Network [OSTI]

    Lave, Matthew S.

    2012-01-01

    Hemker, T. Hoff, Short-term irradiance variability: StationLorenzo, D. Alvira, E. Izco, From irradiance to output power46 High Frequency Irradiance Fluctuations and Geographic

  1. Spark-safe low-voltage detonator

    DOE Patents [OSTI]

    Lieberman, M.L.

    1988-07-01

    A column of explosive in a low-voltage detonator which makes it spark-safe includes an organic secondary explosive charge of HMX in the form of a thin pad disposed in a bore of a housing of the detonator in an ignition region of the explosive column and adjacent to an electrical ignition device at one end of the bore. The pad of secondary charge has an axial thickness within the range of twenty to thirty percent of its diameter. The explosive column also includes a first explosive charge of CP disposed in the housing bore in the ignition region of the explosive column next to the secondary charge pad on a side opposite from the ignition device. The first CP charge is loaded under sufficient pressure, 25 to 40 kpsi, to provide mechanical confinement of the pad of secondary charge and physical coupling thereof with the ignition device. The explosive column further includes a second explosive charge of CP disposed in the housing bore in a transition region of the explosive column next to the first CP charge on a side opposite from the pad of secondary charge. The second CP charge is loaded under sufficient pressure, about 10 kpsi, to allow occurrence of DDT. The first explosive CP charge has an axial thickness within the range of twenty to thirty percent of its diameter, whereas the second explosive CP charge contains a series of increments (nominally 4), each of which has an axial thickness-to-diameter ratio of one to two. 2 figs.

  2. Stabilized radio frequency quadrupole

    DOE Patents [OSTI]

    Lancaster, Henry D. (Orinda, CA); Fugitt, Jock A. (Berkeley, CA); Howard, Donald R. (Danville, CA)

    1984-01-01

    A long-vane stabilized radio frequency resonator for accelerating charged particles and including means defining a radio frequency resonator cavity, a plurality of long vanes mounted in the defining means for dividing the cavity into sections, and means interconnecting opposing ones of the plurality of vanes for stabilizing the resonator.

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

    DOE Patents [OSTI]

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

    1993-01-19

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

  4. Microfabricated ion frequency standard

    DOE Patents [OSTI]

    Schwindt, Peter (Albuquerque, NM); Biedermann, Grant (Albuquerque, NM); Blain, Matthew G. (Albuquerque, NM); Stick, Daniel L. (Albuquerque, NM); Serkland, Darwin K. (Albuquerque, NM); Olsson, III, Roy H. (Albuquerque, NM)

    2010-12-28

    A microfabricated ion frequency standard (i.e. an ion clock) is disclosed with a permanently-sealed vacuum package containing a source of ytterbium (Yb) ions and an octupole ion trap. The source of Yb ions is a micro-hotplate which generates Yb atoms which are then ionized by a ultraviolet light-emitting diode or a field-emission electron source. The octupole ion trap, which confines the Yb ions, is formed from suspended electrodes on a number of stacked-up substrates. A microwave source excites a ground-state transition frequency of the Yb ions, with a frequency-doubled vertical-external-cavity laser (VECSEL) then exciting the Yb ions up to an excited state to produce fluorescent light which is used to tune the microwave source to the ground-state transition frequency, with the microwave source providing a precise frequency output for the ion clock.

  5. IEEE 342 Node Low Voltage Networked Test System

    SciTech Connect (OSTI)

    Schneider, Kevin P.; Phanivong, Phillippe K.; Lacroix, Jean-Sebastian

    2014-07-31

    The IEEE Distribution Test Feeders provide a benchmark for new algorithms to the distribution analyses community. The low voltage network test feeder represents a moderate size urban system that is unbalanced and highly networked. This is the first distribution test feeder developed by the IEEE that contains unbalanced networked components. The 342 node Low Voltage Networked Test System includes many elements that may be found in a networked system: multiple 13.2kV primary feeders, network protectors, a 120/208V grid network, and multiple 277/480V spot networks. This paper presents a brief review of the history of low voltage networks and how they evolved into the modern systems. This paper will then present a description of the 342 Node IEEE Low Voltage Network Test System and power flow results.

  6. IMPACT OF DYNAMIC VOLTAGE SCALING (DVS) ON CIRCUIT OPTIMIZATION 

    E-Print Network [OSTI]

    Esquit Hernandez, Carlos A.

    2010-01-16

    Circuit designers perform optimization procedures targeting speed and power during the design of a circuit. Gate sizing can be applied to optimize for speed, while Dual-VT and Dynamic Voltage Scaling (DVS) can be applied to optimize for leakage...

  7. Time varying voltage combustion control and diagnostics sensor

    DOE Patents [OSTI]

    Chorpening, Benjamin T. (Morgantown, WV); Thornton, Jimmy D. (Morgantown, WV); Huckaby, E. David (Morgantown, WV); Fincham, William (Fairmont, WV)

    2011-04-19

    A time-varying voltage is applied to an electrode, or a pair of electrodes, of a sensor installed in a fuel nozzle disposed adjacent the combustion zone of a continuous combustion system, such as of the gas turbine engine type. The time-varying voltage induces a time-varying current in the flame which is measured and used to determine flame capacitance using AC electrical circuit analysis. Flame capacitance is used to accurately determine the position of the flame from the sensor and the fuel/air ratio. The fuel and/or air flow rate (s) is/are then adjusted to provide reduced flame instability problems such as flashback, combustion dynamics and lean blowout, as well as reduced emissions. The time-varying voltage may be an alternating voltage and the time-varying current may be an alternating current.

  8. Modeling the operating voltage of liquid metal battery cells

    E-Print Network [OSTI]

    Newhouse, Jocelyn Marie

    2014-01-01

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

  9. Unravelling the Performance Degradation Mechanisms in High-voltage...

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

    Unravelling the Performance Degradation Mechanisms in High-voltage Lithium-ion Battery Composite Oxide Electrodes Apr 11 2014 02:00 PM - 03:00 PM Debasish Mohanty, ORNL, Oak Ridge...

  10. Design & Fabrication of a High-Voltage Photovoltaic Cell

    SciTech Connect (OSTI)

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

    2012-09-05

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

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. Voltage-matched configurations for multijunction solar cells

    SciTech Connect (OSTI)

    Gee, J.M.

    1987-01-01

    Novel methods for interconnecting the subcells of a multijunction solar cell are investigated. The subcells are connected in parallel in these new methods. The bandgaps of the subcells must be selected for matched voltages when operated in parallel. We refer to multijunction solar cells with the subcells connected in parallel as having a voltage-matched configuration. Computer analyses of multijunction solar cells with a voltage-matched configuration and with series-connected subcells were performed. Roughly, the same performance with either approach for a multijunction cell with optimized bandgaps was found. Several advantages for the voltage-matched configuration relative to multijunction solar cells with series-connected subcells were identified, including wider selection of bandgaps for optimal performance, less sensitivity to radiation damage, and less sensitivity to spectral variations.

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

    Office of Scientific and Technical Information (OSTI)

    Voltage Solid Polymer Batteries for Electric Drive Vehicles Eitouni, Hany; Yang, Jin; Pratt, Russell; Wang, Xiao; Grape, Ulrik The purpose of this project was for Seeo to develop a...

  17. High-voltage air-core pulse transformers

    SciTech Connect (OSTI)

    Rohwein, G. J.

    1981-01-01

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

  18. Fusing strategies for the dual-voltage fault

    E-Print Network [OSTI]

    Shrivastava, Rupam, 1981-

    2005-01-01

    This thesis focuses on the 42V - 14V fault in a dual voltage system and discusses the possibility of effective fusing. A simple model for the system had been created from technical documentation. Based on the model and the ...

  19. Voltage Dependent Charge Storage Modes and Capacity in Subnanometer Pores

    SciTech Connect (OSTI)

    Qiao, Rui; Meunier, V.; Huang, Jingsong; Wu, Peng; Sumpter, Bobby G

    2012-01-01

    Using molecular dynamics simulations, we show that charge storage in subnanometer pores follows a distinct voltage-dependent behavior. Specifically, at lower voltages, charge storage is achieved by swapping co-ions in the pore with counterions in the bulk electrolyte. As voltage increases, further charge storage is due mainly to the removal of co-ions from the pore, leading to a capacitance increase. The capacitance eventually reaches a maximum when all co-ions are expelled from the pore. At even higher electrode voltages, additional charge storage is realized by counterion insertion into the pore, accompanied by a reduction of capacitance. The molecular mechanisms of these observations are elucidated and provide useful insight for optimizing energy storage based on supercapacitors.

  20. High voltage series connected tandem junction solar battery

    DOE Patents [OSTI]

    Hanak, Joseph J. (Lawrenceville, NJ)

    1982-01-01

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

  1. Measuring Helical FCG Voltage with an Electric Field Antenna

    SciTech Connect (OSTI)

    White, A D; Anderson, R A; Javedani, J B; Reisman, D B; Goerz, D A; Ferriera, A J; Speer, R D

    2011-08-01

    A method of measuring the voltage produced by a helical explosive flux compression generator using a remote electric field antenna is described in detail. The diagnostic has been successfully implemented on several experiments. Measured data from the diagnostic compare favorably with voltages predicted using the code CAGEN, validating our predictive modeling tools. The measured data is important to understanding generator performance, and is measured with a low-risk, minimally intrusive approach.

  2. Soft Magnetic Materials in High-Frequency, High-Power Conversion Applications

    E-Print Network [OSTI]

    McHenry, Michael E.

    and facilitate two-way power conversion.7 Flexible alternating current (AC) Transmission Systems (FACTS) and High Voltage DC (HVDC) technologies aim to improve the effi- ciency of power networks and benefit from highSoft Magnetic Materials in High-Frequency, High-Power Conversion Applications ALEX M. LEARY,1

  3. Frequency-selective Power Transducers "Hexagonal Ferrite Resonator--Semiconductor Element"

    E-Print Network [OSTI]

    Koledintseva, Marina Y.

    -effect voltage. The conversion co- efficient of a transducer is analyzed using the power balance equation. Some contains a primary measuring transducer and a secondary processing/display unit. A primary transducer frequency selectivity of power conversion. 2. Mathematical Model for the Conversion Coefficient

  4. IEEE SIGNAL PROCESSING LETTERS, VOL. 20, NO. 6, JUNE 2013 575 Joint Frequency and Phasor Estimation

    E-Print Network [OSTI]

    Tong, Lang

    , constrained maximum likelihood estimation, frequency estimation, phasor measurement unit (PMU), power system in the context of power system state estimation using phasor measurement units (PMUs). A key feature of PMU meters period. PMU provides syn- chronized direct measurements of bus voltages and currents. Under normal

  5. Viscoelastic effects on frequency tuning of a dielectric elastomer membrane resonator

    SciTech Connect (OSTI)

    Zhou, Jianyou; Jiang, Liying, E-mail: lyjiang@eng.uwo.ca; Khayat, Roger E. [Department of Mechanical and Materials Engineering, The University of Western Ontario, London, Ontario N6A 5B9 (Canada)

    2014-03-28

    As a recent application of dielectric elastomers (DEs), DE resonators have become an alternative to conventional silicon-based resonators used in MEMS and have attracted much interest from the research community. However, most existing modeling works for the DE resonators ignore the intrinsic viscoelastic effect of the material that may strongly influence their dynamic performance. Based on the finite-deformation viscoelasticity theory for dielectrics, this paper theoretically examines the in-plane oscillation of a DE membrane resonator to demonstrate how the material viscoelasticity affects the actuation and frequency tuning processes of the resonator. From the simulation results, it is concluded that not only the applied voltage can change the natural frequency of the resonator, but also the inelastic deformation contributes to frequency tuning. Due to the viscoelasticity of the material, the electrical loading rate influences the actuation process of the DE resonator, while it has little effect on the final steady frequency tuned by the prescribed voltage within the safety range. With the consideration of the typical failure modes of the resonator and the evolution process of the material, the tunable frequency range and the safe range of the applied voltage of the DE membrane resonator with different dimension parameters are determined in this work, which are found to be dependent on the electrical loading rate. This work is expected to provide a better understanding on the frequency tuning of viscoelastic DE membrane resonators and a guideline for the design of DE devices.

  6. Graphene Frequency Multipliers

    E-Print Network [OSTI]

    Wang, Han

    In this letter, the ambipolar transport properties of graphene flakes have been used to fabricate full-wave signal rectifiers and frequency-doubling devices. By correctly biasing an ambipolar graphene field-effect transistor ...

  7. High-frequency electric field measurement using a toroidal antenna

    SciTech Connect (OSTI)

    Lee, K.H.

    1997-01-01

    In this paper the author describes an innovative method of measuring high-frequency electric fields using a toroid. For typical geophysical applications the new sensor will detect electric fields for a wide range of spectrum starting from 1.0 MHz. This window, in particular the lower frequency range between 1.0 to 100 MHz, has not been used for existing electromagnetic or radar systems to detect small objects in the upper few meters of the ground. Ground penetrating radar (GPR) can be used successfully in this depth range if the ground is resistive but most soils are, in fact, conductive (0.01 to 1.0 S/m) rendering GPR inefficient. Other factors controlling the resolution of GPR system for small objects is the spatial averaging inherent in the electric dipole antenna and the scattering caused by soil inhomogeneities of dimensions comparable to the wavelength (and antenna size). For maximum resolution it is desirable to use the highest frequencies but the scattering is large and target identification is poor. Time-varying magnetic fields induce an emf (voltage) in a toroid. The electric field at the center of the toroid is shown to be linearly related to this induced voltage. By measuring the voltage across a toroid one can easily and accurately determine the electric field. The new sensor will greatly simplify the cumbersome procedure involved with GPR measurements with its center frequency less than 100 MHz. The overall size of the toroidal sensor can be as small as a few inches. It is this size advantage that will not only allow easy fabrication and deployment of multi-component devices either on the surface or in a borehole, but it will render greatly improved resolution over conventional systems.

  8. High-frequency internal waves on a sloping shelf James M. Pringle1

    E-Print Network [OSTI]

    Pringle, James "Jamie"

    1 High-frequency internal waves on a sloping shelf James M. Pringle1 and Kenneth H. Brink Woods field propagating across a shelf and hence control the high- frequency variability on the shelf. This analysis exam- ines the evolution of the high-frequency internal wave field on the shelf as it is modified

  9. PV output variability modeling using satellite imagery.

    SciTech Connect (OSTI)

    Stein, Joshua S.; Ellis, Abraham; Reno, Matthew J.

    2010-11-01

    High frequency irradiance variability measured on the ground is caused by the formation, dissipation, and passage of clouds in the sky. If we can identify and associate different cloud types/patterns from satellite imagery, we may be able to predict irradiance variability in areas lacking sensors. With satellite imagery covering the entire U.S., this allows for more accurate integration planning and power flow modeling over wide areas. Satellite imagery from southern Nevada was analyzed at 15 minute intervals over a year. Methods for image stabilization, cloud detection, and textural classification of clouds were developed and tested. High Performance Computing parallel processing algorithms were also investigated and tested. Artificial Neural Networks using imagery as inputs were trained on ground-based measurements of irradiance to model the variability and were tested to show some promise as a means for predicting irradiance variability.

  10. Evaluation of electropolished stainless steel electrodes for use in DC high voltage photoelectron guns

    SciTech Connect (OSTI)

    BastaniNejad, Mahzad; Elmustafa, Abdelmageed A.; Forman, Eric; Covert, Steven; Hansknecht, John; Hernandez-Garcia, Carlos; Poelker, Matthew; Das, Lopa; Kelley, Michael; Williams, Phillip

    2015-07-01

    DC high voltage photoelectron guns are used to produce polarized electron beams for accelerator-based nuclear and high-energy physics research. Low-level field emission (~nA) from the cathode electrode degrades the vacuum within the photogun and reduces the photoelectron yield of the delicate GaAs-based photocathode used to produce the electron beams. High-level field emission (>?A) can cause significant damage the photogun. To minimize field emission, stainless steel electrodes are typically diamond-paste polished, a labor-intensive process often yielding field emission performance with a high degree of variability, sample to sample. As an alternative approach and as comparative study, the performance of electrodes electropolished by conventional commercially available methods is presented. Our observations indicate the electropolished electrodes exhibited less field emission upon the initial application of high voltage, but showed less improvement with gas conditioning compared to the diamond-paste polished electrodes. In contrast, the diamond-paste polished electrodes responded favorably to gas conditioning, and ultimately reached higher voltages and field strengths without field emission, compared to electrodes that were only electropolished. The best performing electrode was one that was both diamond-paste polished and electropolished, reaching a field strength of 18.7 MV/m while generating less than 100 pA of field emission. The speculate that the combined processes were the most effective at reducing both large and small scale topography. However, surface science evaluation indicates topography cannot be the only relevant parameter when it comes to predicting field emission performance.

  11. Evaluation of electropolished stainless steel electrodes for use in DC high voltage photoelectron guns

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

    BastaniNejad, Mahzad; Elmustafa, Abdelmageed A.; Forman, Eric; Covert, Steven; Hansknecht, John; Hernandez-Garcia, Carlos; Poelker, Matthew; Das, Lopa; Kelley, Michael; Williams, Phillip

    2015-07-01

    DC high voltage photoelectron guns are used to produce polarized electron beams for accelerator-based nuclear and high-energy physics research. Low-level field emission (~nA) from the cathode electrode degrades the vacuum within the photogun and reduces the photoelectron yield of the delicate GaAs-based photocathode used to produce the electron beams. High-level field emission (>?A) can cause significant damage the photogun. To minimize field emission, stainless steel electrodes are typically diamond-paste polished, a labor-intensive process often yielding field emission performance with a high degree of variability, sample to sample. As an alternative approach and as comparative study, the performance of electrodes electropolishedmore »by conventional commercially available methods is presented. Our observations indicate the electropolished electrodes exhibited less field emission upon the initial application of high voltage, but showed less improvement with gas conditioning compared to the diamond-paste polished electrodes. In contrast, the diamond-paste polished electrodes responded favorably to gas conditioning, and ultimately reached higher voltages and field strengths without field emission, compared to electrodes that were only electropolished. The best performing electrode was one that was both diamond-paste polished and electropolished, reaching a field strength of 18.7 MV/m while generating less than 100 pA of field emission. The speculate that the combined processes were the most effective at reducing both large and small scale topography. However, surface science evaluation indicates topography cannot be the only relevant parameter when it comes to predicting field emission performance.« less

  12. Evaluation of electropolished stainless steel electrodes for use in DC high voltage photoelectron guns

    SciTech Connect (OSTI)

    BastaniNejad, Mahzad Elmustafa, Abdelmageed A.; Forman, Eric; Covert, Steven; Hansknecht, John; Hernandez-Garcia, Carlos; Poelker, Matthew; Das, Lopa; Kelley, Michael; Williams, Phillip

    2015-07-15

    DC high voltage photoelectron guns are used to produce polarized electron beams for accelerator-based nuclear and high-energy physics research. Low-level field emission (?nA) from the cathode electrode degrades the vacuum within the photogun and reduces the photoelectron yield of the delicate GaAs-based photocathode used to produce the electron beams. High-level field emission (>?A) can cause significant damage the photogun. To minimize field emission, stainless steel electrodes are typically diamond-paste polished, a labor-intensive process often yielding field emission performance with a high degree of variability, sample to sample. As an alternative approach and as comparative study, the performance of electrodes electropolished by conventional commercially available methods is presented. Our observations indicate the electropolished electrodes exhibited less field emission upon the initial application of high voltage, but showed less improvement with gas conditioning compared to the diamond-paste polished electrodes. In contrast, the diamond-paste polished electrodes responded favorably to gas conditioning, and ultimately reached higher voltages and field strengths without field emission, compared to electrodes that were only electropolished. The best performing electrode was one that was both diamond-paste polished and electropolished, reaching a field strength of 18.7 MV/m while generating less than 100?pA of field emission. The authors speculate that the combined processes were the most effective at reducing both large and small scale topography. However, surface science evaluation indicates topography cannot be the only relevant parameter when it comes to predicting field emission performance.

  13. Low voltage supply system for the very front end readout electronics of the CMS electromagnetic calorimeter

    E-Print Network [OSTI]

    Lustermann, W; Denes, P; Djambazov, L; Dröge, M; Faure, J L; Iliev, Bozhidar Z; Nanov, I; Raykov, P; Shivarov, N

    1999-01-01

    Low voltage supply system for the very front end readout electronics of the CMS electromagnetic calorimeter

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

    SciTech Connect (OSTI)

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

    2011-02-01

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

  15. Ultra-Low Voltage VCO Design Using Schmitt Trigger on SOI

    E-Print Network [OSTI]

    Ayers, Joseph

    Ultra-Low Voltage VCO Design Using Schmitt Trigger on SOI Kyung Ki Kim Department of Electrical trigger and an ultra low voltage current source on PD-SOI with low temperature and supply voltage oscillator based VCOs on SOI CMOS [4][5] have been reported. However, VCO with ultra low voltage less than 0

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

    DOE Patents [OSTI]

    Righter, Alan W. (Albuquerque, NM)

    1996-01-01

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

  17. Voltage sensing in ion channels: Mesoscale simulations of biological devices

    E-Print Network [OSTI]

    Peyser, Alexander

    2012-01-01

    Electrical signaling via voltage-gated ion channels depends upon the function of a voltage sensor (VS), identified with the S1-S4 domain in voltage-gated K+ channels. Here we investigate some energetic aspects of the sliding-helix model of the VS using simulations based on VS charges, linear dielectrics and whole-body motion. Model electrostatics in voltage-clamped boundary conditions are solved using a boundary element method. The statistical mechanical consequences of the electrostatic configurational energy are computed to gain insight into the sliding-helix mechanism and to predict experimentally measured ensemble properties such as gating charge displaced by an applied voltage. Those consequences and ensemble properties are investigated for two alternate S4 configurations, \\alpha- and 3(10)-helical. Both forms of VS are found to have an inherent electrostatic stability. Maximal charge displacement is limited by geometry, specifically the range of movement where S4 charges and counter-charges overlap in t...

  18. Voltage control in pulsed system by predict-ahead control

    DOE Patents [OSTI]

    Payne, A.N.; Watson, J.A.; Sampayan, S.E.

    1994-09-13

    A method and apparatus for predict-ahead pulse-to-pulse voltage control in a pulsed power supply system is disclosed. A DC power supply network is coupled to a resonant charging network via a first switch. The resonant charging network is coupled at a node to a storage capacitor. An output load is coupled to the storage capacitor via a second switch. A de-Q-ing network is coupled to the resonant charging network via a third switch. The trigger for the third switch is a derived function of the initial voltage of the power supply network, the initial voltage of the storage capacitor, and the present voltage of the storage capacitor. A first trigger closes the first switch and charges the capacitor. The third trigger is asserted according to the derived function to close the third switch. When the third switch is closed, the first switch opens and voltage on the node is regulated. The second trigger may be thereafter asserted to discharge the capacitor into the output load. 4 figs.

  19. A study of temperature compensating circuits for voltage references which use negative temperature coefficient zener diodes 

    E-Print Network [OSTI]

    Coleman, Spencer Delano

    1961-01-01

    OF FIGURES Figure Page Zener Diode Voltage vs Current Characteristics. Zener Diode Breakdown Voltage vs Temperature Coefficient . 3a. 1N746 Zener Diode Voltage vs Current Character- istics in Breakdown Region 3b. 1N747 Zener Diode Voltage vs Current... Character- istics in Breakdown Region 10 3c. 1N748 Zener Diode Voltage vs Current Character- istics in Breakdown Region 3d. 1N749 Zener Diode Voltage vs Current Character- istics in Breakdown Region . 12 3e. IN750 Zener Diode Voltage vs Current...

  20. Voltage Impacts of Utility-Scale Distributed Wind

    SciTech Connect (OSTI)

    Allen, A.

    2014-09-01

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

  1. Digital measurement system for the LHC klystron high voltage modulator.

    E-Print Network [OSTI]

    Mikkelsen, Anders

    Accelerating voltage in the Large Hadron Collider (LHC) is created by a means of 16 superconducting standing wave RF cavities, each fed by a 400MHz/300kW continuous wave klystron amplifier. Part of the upgrade program for the LHC long shutdown one is to replace the obsolete analogue current and voltage measurement circuitry located in the high voltage bunkers by a new, digital system, using ADCs and optical fibres. A digital measurement card is implemented and integrated into the current HV modulator oil tank (floating at -58kV) and interfaced to the existing digital VME boards collecting the data for several klystrons at the ground potential. Measured signals are stored for the logging, diagnostics and post-mortem analysis purposes.

  2. Method of determining the open circuit voltage of a battery in a closed circuit

    DOE Patents [OSTI]

    Brown, William E. (Walnut Creek, CA)

    1980-01-01

    The open circuit voltage of a battery which is connected in a closed circuit is determined without breaking the circuit or causing voltage upsets therein. The closed circuit voltage across the battery and the current flowing through it are determined under normal load and then a fractional change is made in the load and the new current and voltage values determined. The open circuit voltage is then calculated, according to known principles, from the two sets of values.

  3. Low-voltage ultra-low-poweranalog IC design -djmamic translinearcircuits 1.3.1 1.3 Low-voltage ultra-low-power analog IC design

    E-Print Network [OSTI]

    Serdijn, Wouter A.

    Low-voltage ultra-low-poweranalog IC design -djmamic translinearcircuits 1.3.1 1.3 Low-voltage ultra-low-power analog IC design -dynamic translinear circuits 0 (rg G x m .- E . . . . . a r, a" P, 44' s" +N m - _ c o3 #12;Low-voltage ultra-low-power analog IC design -dynamic translinear circuits I

  4. Computational study of plasma sustainability in radio frequency micro-discharges

    SciTech Connect (OSTI)

    Zhang, Y.; Jiang, W.; Zhang, Q. Z.; Bogaerts, A.

    2014-05-21

    We apply an implicit particle-in-cell Monte-Carlo (PIC-MC) method to study a radio-frequency argon microdischarge at steady state in the glow discharge limit, in which the microdischarge is sustained by secondary electron emission from the electrodes. The plasma density, electron energy distribution function (EEDF), and electron temperature are calculated in a wide range of operating conditions, including driving voltage, microdischarge gap, and pressure. Also, the effect of gap size scaling (in the range of 50-1000??m) on the plasma sustaining voltage and peak electron density at atmospheric pressure is examined, which has not been explored before. In our simulations, three different EEDFs, i.e., a so-called three temperature hybrid mode, a two temperature ? mode, and a two temperature ? mode distribution, are identified at different gaps and voltages. The maximum sustaining voltage to avoid a transition from the glow mode to an arc is predicted, as well as the minimum sustaining voltage for a steady glow discharge. Our calculations elucidate that secondary electrons play an essential role in sustaining the discharge, and as a result the relationship between breakdown voltage and gap spacing is far away from the Paschen law at atmospheric pressure.

  5. High voltage switch triggered by a laser-photocathode subsystem

    DOE Patents [OSTI]

    Chen, Ping; Lundquist, Martin L.; Yu, David U. L.

    2013-01-08

    A spark gap switch for controlling the output of a high voltage pulse from a high voltage source, for example, a capacitor bank or a pulse forming network, to an external load such as a high gradient electron gun, laser, pulsed power accelerator or wide band radar. The combination of a UV laser and a high vacuum quartz cell, in which a photocathode and an anode are installed, is utilized as triggering devices to switch the spark gap from a non-conducting state to a conducting state with low delay and low jitter.

  6. Low frequency phase signal measurement with high frequency squeezing

    E-Print Network [OSTI]

    Zehui Zhai; Jiangrui Gao

    2011-08-24

    We calculate the utility of high-frequency squeezed-state enhanced two-frequency interferometry for low-frequency phase measurement. To use the high-frequency sidebands of the squeezed light, a two-frequency intense laser is used in the interferometry instead of a single-frequency laser as usual. We find that the readout signal can be contaminated by the high-frequency phase vibration, but this is easy to check and avoid. A proof-of-principle experiment is in the reach of modern quantum optics technology.

  7. Translocation frequency of double-stranded DNA through a solid-state nanopore

    E-Print Network [OSTI]

    Bell, Nicholas A W; Keyser, Ulrich F

    2015-01-01

    Solid-state nanopores are single molecule sensors that measure changes in ionic current as charged polymers such as DNA pass through. Here, we present comprehensive experiments on the length, voltage and salt dependence of the frequency of double-stranded DNA translocations through conical quartz nanopores with mean opening diameter 15 nm. We observe an entropic barrier limited, length dependent translocation frequency at 4M LiCl salt concentration and a drift-dominated, length independent translocation frequency at 1M KCl salt concentration. These observations are described by a unifying convection-diffusion equation which includes the contribution of an entropic barrier for polymer entry.

  8. Dual frequency optical cavity

    DOE Patents [OSTI]

    George, E. Victor (Livermore, CA); Schipper, John F. (Palo Alto, CA)

    1985-01-01

    Method and apparatus for generating two distinct laser frequencies in an optical cavity, using a "T" configuration laser cavity and means for intermittently increasing or decreasing the index of refraction n of an associated transmission medium in one arm of the optical cavity to enhance laser action in one arm or the second arm of the cavity.

  9. Investigation and optimization of low-frequency noise performance in readout electronics of dc superconducting quantum interference device

    SciTech Connect (OSTI)

    Zhao, Jing; Zhang, Yi; Krause, Hans-Joachim; Lee, Yong-Ho

    2014-05-15

    We investigated and optimized the low-frequency noise characteristics of a preamplifier used for readout of direct current superconducting quantum interference devices (SQUIDs). When the SQUID output was detected directly using a room-temperature low-voltage-noise preamplifier, the low-frequency noise of a SQUID system was found to be dominated by the input current noise of the preamplifiers in case of a large dynamic resistance of the SQUID. To reduce the current noise of the preamplifier in the low-frequency range, we investigated the dependence of total preamplifier noise on the collector current and source resistance. When the collector current was decreased from 8.4 mA to 3 mA in the preamplifier made of 3 parallel SSM2220 transistor pairs, the low-frequency total voltage noise of the preamplifier (at 0.1 Hz) decreased by about 3 times for a source resistance of 30 ? whereas the white noise level remained nearly unchanged. Since the relative contribution of preamplifier's input voltage and current noise is different depending on the dynamic resistance or flux-to-voltage transfer of the SQUID, the results showed that the total noise of a SQUID system at low-frequency range can be improved significantly by optimizing the preamplifier circuit parameters, mainly the collector current in case of low-noise bipolar transistor pairs.

  10. Ashtekar's variables without spin

    E-Print Network [OSTI]

    Thomas Schucker

    2009-06-26

    Ashtekar's variables are shown to arise naturally from a 3+1 split of general relativity in the Einstein-Cartan formulation. Thereby spinors are exorcised.

  11. Frequency Control Performance Measurement and Requirements

    E-Print Network [OSTI]

    Illian, Howard F.

    2011-01-01

    DCS only measured low-frequency disturbances instead of bothlow- and high-frequency disturbances. The DCS requiredof the pre-disturbance frequency and the settling frequency.

  12. Primary Voltage Control in Active Distribution Networks via Broadcast Signals

    E-Print Network [OSTI]

    Diggavi, Suhas

    energy storage. We show that it is possible to use the same broadcast signal deployed for controlling) for real-time demand response developed by the authors in a previous contribution. We estimate the energy--Active distribution network, ancillary services, primary voltage control, electrical energy storage systems, broad

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

    E-Print Network [OSTI]

    modeling is mentioned, it refers to using industry accepted distribution system power flow simulation tools the verification process. · Calculations of all system improvements (reduction of line losses and no-load lossesSimplified VO M&V Protocol 1 Simplified Voltage Optimization (VO) Measurement and Verification

  14. Smart Grid Voltage Sag Detection using Instantaneous Features Extraction

    E-Print Network [OSTI]

    Boyer, Edmond

    encountered power quality disturbances. Index Terms--Smart grid, voltage sag detection, power quality (PQ as the generation system is moved nearby the distribution level and this is achieved by using a set of micro grids grids are their availability, reliability, and profitability; in order to fulfill power demand according

  15. DEVELOPMENT OF BROADBAND LOW-VOLTAGE RF MEM SWITCHES

    E-Print Network [OSTI]

    Shen, Shyh-Chiang

    DEVELOPMENT OF BROADBAND LOW-VOLTAGE RF MEM SWITCHES S.C. Shen, D. T. Becher, D. C. Caruth, and M)333-4054 Fax: (217) 244-6375 Abstract We present novel RF switches using micro-electro- mechanical (MEM) technology. These MEM switches are built on GaAs substrates using GaAs MESFET MMIC- compatible processes

  16. CompilerDirected Dynamic Voltage Scaling Based on Program Regions

    E-Print Network [OSTI]

    Kremer, Ulrich

    '' the degraded CPU performance behind the memory hierarchy accesses which are on the critical path. The compiler. processor that can operate over a wide voltage range. The operating system controls the processor speed user environment, but not in a multi­user environment where the CPU is scheduled across di#erent active

  17. Control and Protection Cooperation Strategy for Voltage Instability

    E-Print Network [OSTI]

    Chen, Zhe

    are caused by unexpected backup relay operations due to low voltage or overload state caused by post fault load restoration dynamics. If such state can be sensed and adjusted appropriately prior to those relay adopted to save the system from severe states. A test system is built in real time digital simulator (RTDS

  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. 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

  20. Chronic Benzodiazepine Administration Potentiates High Voltage-Activated Calcium Currents

    E-Print Network [OSTI]

    Abraham, Nader G.

    effects from drug withdrawal phenomena to dependence on a variety of drugs of abuse. High voltage benzodiazepine physical dependence. Benzodiazepines, a group of positive allosteric modulators of GABAA receptors legitimate prescription of benzodiazepines increases the proportion of patients who develop dependence

  1. Topical Review Voltage Dependence of the Na/K Pump

    E-Print Network [OSTI]

    Gadsby, David

    Topical Review Voltage Dependence of the Na/K Pump R.F. Rakowski1 , D.C. Gadsby2 , P. De Weer3 1, Philadelphia, PA 19104, USA Received: 2 August 1996/Revised: 13 September 1996 Introduction Whether Na/K pump & Rakowski, 1988). While it follows from first principles that the rate of net forward Na/K pumping must

  2. Coupled Dual Interleaved Flyback Converter for High Input Voltage Application

    E-Print Network [OSTI]

    Lehman, Brad

    proposed integrated boost converters [7] that are beginning to see applications in automotive power buck-boost (Flyback) power converter [9,10] that utilizes one magnetic core to integrate two FlybackCoupled Dual Interleaved Flyback Converter for High Input Voltage Application Ting Qian, Brad

  3. Energy Optimization of Subthreshold-Voltage Sensor Network Processors

    E-Print Network [OSTI]

    Dutta, Prabal

    network processor results. This design, accompanied by bulk-silicon solar cells for energy scavenging, hasEnergy Optimization of Subthreshold-Voltage Sensor Network Processors Leyla Nazhandali, Bo ZhaiV and be- low) lends itself well to the performance and energy demands of sensor network processors

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

    E-Print Network [OSTI]

    Toumpis, Stavros

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

  5. Enhanced Archaerhodopsin Fluorescent Protein Voltage Yiyang Gong1,2*

    E-Print Network [OSTI]

    Ferrari, Silvia

    Enhanced Archaerhodopsin Fluorescent Protein Voltage Indicators Yiyang Gong1,2* , Jin Zhong Li1 by nearly three-fold in comparison to Arch-D95N. Citation: Gong Y, Li JZ, Schnitzer MJ (2013) Enhanced; Published June 19, 2013 Copyright: © 2013 Gong et al. This is an open-access article distributed under

  6. Energy Efficiency in Low Voltage Hall Thrusters Jerry L. Ross

    E-Print Network [OSTI]

    King, Lyon B.

    Energy Efficiency in Low Voltage Hall Thrusters Jerry L. Ross Lyon B. King Energy efficiency/s of xenon. Acceleration and current efficiencies were compared to thrust efficiency over a range of magnet coil current values of 0 A - 2.5 A. Acceleration efficiencies were obtained with a 4-grid Retarding

  7. Standby Voltage Scaling for Reduced Power B. Calhoun, A. Chandrakasan

    E-Print Network [OSTI]

    Calhoun, Benton H.

    Engineering Massachusetts Institute of Technology, Cambridge, MA Abstract Lowering VDD during standby mode leakage, gate leakage, GIDL, and forward biased diode leak- age[2]. At the 0.13 m technology node to pinch in the rail voltages during standby[5]. The quantity and sizes of the devices used in the diode

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

    SciTech Connect (OSTI)

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

    2009-05-01

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

  9. Optical Spectra of the High Voltage Erosive Water Discharge

    E-Print Network [OSTI]

    Pirozerski, A L

    2008-01-01

    In the present paper kinetics of emission spectra of the high voltage erosive water discharge at near ultraviolet and visible spectral ranges has been investigated. Obtained results show a similarity of physical properties of this discharge (and of corresponding plasmoids) to that of some other types of erosional discharges which also result in the formation of dust-gas fireballs.

  10. Ultra-compact Marx-type high-voltage generator

    DOE Patents [OSTI]

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

    2000-01-01

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

  11. Power Grid Voltage Integrity Verification Department of ECE

    E-Print Network [OSTI]

    Najm, Farid N.

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

  12. System and method of modulating electrical signals using photoconductive wide bandgap semiconductors as variable resistors

    DOE Patents [OSTI]

    Harris, John Richardson; Caporaso, George J; Sampayan, Stephen E

    2013-10-22

    A system and method for producing modulated electrical signals. The system uses a variable resistor having a photoconductive wide bandgap semiconductor material construction whose conduction response to changes in amplitude of incident radiation is substantially linear throughout a non-saturation region to enable operation in non-avalanche mode. The system also includes a modulated radiation source, such as a modulated laser, for producing amplitude-modulated radiation with which to direct upon the variable resistor and modulate its conduction response. A voltage source and an output port, are both operably connected to the variable resistor so that an electrical signal may be produced at the output port by way of the variable resistor, either generated by activation of the variable resistor or propagating through the variable resistor. In this manner, the electrical signal is modulated by the variable resistor so as to have a waveform substantially similar to the amplitude-modulated radiation.

  13. High-output microwave detector using voltage-induced ferromagnetic resonance

    SciTech Connect (OSTI)

    Shiota, Yoichi Suzuki, Yoshishige; Miwa, Shinji; Tamaru, Shingo; Nozaki, Takayuki; Kubota, Hitoshi; Fukushima, Akio; Yuasa, Shinji

    2014-11-10

    We investigated the voltage-induced ferromagnetic resonance (FMR) with various DC bias voltage and input RF power in magnetic tunnel junctions. We found that the DC bias monotonically increases the homodyne detection voltage due to the nonlinear FMR originating in an asymmetric magnetization-potential in the free layer. In addition, the linear increase of an output voltage to the input RF power in the voltage-induced FMR is more robust than that in spin-torque FMR. These characteristics enable us to obtain an output voltage more than ten times than that of microwave detectors using spin-transfer torque.

  14. Method and apparatus for calibrating a linear variable differential transformer

    DOE Patents [OSTI]

    Pokrywka, Robert J. (North Huntingdon, PA)

    2005-01-18

    A calibration apparatus for calibrating a linear variable differential transformer (LVDT) having an armature positioned in au LVDT armature orifice, and the armature able to move along an axis of movement. The calibration apparatus includes a heating mechanism with an internal chamber, a temperature measuring mechanism for measuring the temperature of the LVDT, a fixture mechanism with an internal chamber for at least partially accepting the LVDT and for securing the LVDT within the heating mechanism internal chamber, a moving mechanism for moving the armature, a position measurement mechanism for measuring the position of the armature, and an output voltage measurement mechanism. A method for calibrating an LVDT, including the steps of: powering the LVDT; heating the LVDT to a desired temperature; measuring the position of the armature with respect to the armature orifice; and measuring the output voltage of the LVDT.

  15. Electron-beam-induced domain poling in LiNbO3 for two-dimensional nonlinear frequency conversion

    E-Print Network [OSTI]

    Arie, Ady

    Electron-beam-induced domain poling in LiNbO3 for two-dimensional nonlinear frequency conversion to achieve noncollinear second-harmonic generation. The sample was fabricated using an electron-beam indirect electron-beam poling,1 electric-field poling,2 and high-voltage atomic force microscop AFM .3

  16. Novel techniques for fault location, voltage profile calculation and visualization of transients 

    E-Print Network [OSTI]

    Evrenosoglu, Cansin Yaman

    2009-05-15

    techniques of voltage profiles along transmission lines. A simple yet effective approach to accurately and rapidly obtain the voltage profile along a transmission line during fault transients is presented. The objective of the presented method is to eliminate...

  17. Voltage and Timing Adaptation for Variation and Aging Tolerance in Nanometer VLSI Circuits 

    E-Print Network [OSTI]

    Shim, Kyu-Nam 1978-

    2012-09-10

    . Adaptive supply voltage (ASV) is one of the effective adaptation approaches for power-performance tuning. ASV has advantages on controlling dynamic and leakage power, while voltage generation and delivery overheads from conventional ASV systems make...

  18. Switched-capacitor step-down rectifier for low-voltage power conversion

    E-Print Network [OSTI]

    Li, Wei

    This paper presents a switched-capacitor rectifier that provides step down voltage conversion from an ac input voltage to a dc output. Coupled with current-drive source, low-loss and high step-down rectification is realized. ...

  19. Improve Motor Operation at Off-Design Voltages - Motor Tip Sheet #9

    SciTech Connect (OSTI)

    2008-07-01

    Motors are designed to operate within +/- 10% of their nameplate rated voltages. When motors operate at conditions of over- or under-voltage, motor efficiency and other performance parameters are degraded.

  20. Voltage Control of Distribution Networks with Distributed Generation using Reactive Power

    E-Print Network [OSTI]

    Pota, Himanshu Roy

    , photovoltaics, and synchronous generators. I. INTRODUCTION Penetration of DG into distribution network in terms of voltage profile improvement, line-loss reduction, and environmental impact reductionVoltage Control of Distribution Networks with Distributed Generation using Reactive Power

  1. Incorporating voltage security into the planning, operation and monitoring of restructured electric energy markets 

    E-Print Network [OSTI]

    Nair, Nirmal-Kumar

    2006-04-12

    state voltage stability index to detect potential dynamic voltage collapse. Finally, this dissertation examines developments in representation, standardization, communication and exchange of power system data. Power system data is the key input to all...

  2. Interline photovoltaic (I-PV) power plants for voltage unbalance compensation

    E-Print Network [OSTI]

    Moawwad, Ahmed

    This paper proposes a stationary-frame control method for voltage unbalance compensation using Interline Photovoltaic (I-PV) power system. I-PV power systems are controlled to compensate voltage unbalance autonomously. The ...

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

    E-Print Network [OSTI]

    Lavaei, Javad

    or insufficient reactive power supplies may also contribute to voltage collapse and blackouts. In recent years, the voltage collapse or blackouts have occurred worldwide, such as the blackout in France at 1978 and blackout

  4. Optimal Distributed Voltage Regulation in Power Distribution Networks

    E-Print Network [OSTI]

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

    2012-01-01

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

  5. Analysis of Solar Cell Quality Using Voltage Metrics: Preprint

    SciTech Connect (OSTI)

    Toberer, E. S.; Tamboli, A. C.; Steiner, M.; Kurtz, S.

    2012-06-01

    The highest efficiency solar cells provide both excellent voltage and current. Of these, the open-circuit voltage (Voc) is more frequently viewed as an indicator of the material quality. However, since the Voc also depends on the band gap of the material, the difference between the band gap and the Voc is a better metric for comparing material quality of unlike materials. To take this one step further, since Voc also depends on the shape of the absorption edge, we propose to use the ultimate metric: the difference between the measured Voc and the Voc calculated from the external quantum efficiency using a detailed balance approach. This metric is less sensitive to changes in cell design and definition of band gap. The paper defines how to implement this metric and demonstrates how it can be useful in tracking improvements in Voc, especially as Voc approaches its theoretical maximum.

  6. Understanding Biomass Feedstock Variability

    SciTech Connect (OSTI)

    Kevin L. Kenney; William A. Smith; Garold L. Gresham; Tyler L. Westover

    2013-01-01

    If the singular goal of biomass logistics and the design of biomass feedstock supply systems is to reduce the per ton supply cost of biomass, these systems may very well develop with ultimate unintended consequences of highly variable and reduced quality biomass feedstocks. This paper demonstrates that due to inherent species variabilities, production conditions, and differing harvest, collection, and storage practices, this is a very real scenario that biomass producers and suppliers as well as conversion developers should be aware of. Biomass feedstock attributes of ash, carbohydrates, moisture, and particle morphology will be discussed. We will also discuss specifications for these attributes, inherent variability of these attributes in biomass feedstocks, and approaches and solutions for reducing variability for improving feedstock quality.

  7. Understanding Biomass Feedstock Variability

    SciTech Connect (OSTI)

    Kevin L. Kenney; Garold L. Gresham; William A. Smith; Tyler L. Westover

    2013-01-01

    If the singular goal of biomass logistics and the design of biomass feedstock supply systems is to reduce the per-ton supply cost of biomass, these systems may very well develop with ultimate unintended consequences of highly variable and reduced quality biomass feedstocks. This paper demonstrates that, due to inherent species variabilities, production conditions and differing harvest, collection and storage practices, this is a very real scenario that biomass producers and suppliers as well as conversion developers should be aware of. Biomass feedstock attributes of ash, carbohydrates, moisture and particle morphology will be discussed. We will also discuss specifications for these attributes, inherent variability of these attributes in biomass feedstocks, and approaches and solutions for reducing variability for improving feedstock quality.

  8. Magnetic shielding of Hall thrusters at high discharge voltages

    SciTech Connect (OSTI)

    Mikellides, Ioannis G., E-mail: Ioannis.G.Mikellides@jpl.nasa.gov; Hofer, Richard R.; Katz, Ira; Goebel, Dan M. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 (United States)

    2014-08-07

    A series of numerical simulations and experiments have been performed to assess the effectiveness of magnetic shielding in a Hall thruster operating in the discharge voltage range of 300–700?V (I{sub sp}???2000–2700?s) at 6?kW, and 800?V (I{sub sp} ? 3000) at 9?kW. At 6?kW, the magnetic field topology with which highly effective magnetic shielding was previously demonstrated at 300?V has been retained for all other discharge voltages; only the magnitude of the field has been changed to achieve optimum thruster performance. It is found that magnetic shielding remains highly effective for all discharge voltages studied. This is because the channel is long enough to allow hot electrons near the channel exit to cool significantly upon reaching the anode. Thus, despite the rise of the maximum electron temperature in the channel with discharge voltage, the electrons along the grazing lines of force remain cold enough to eliminate or reduce significantly parallel gradients of the plasma potential near the walls. Computed maximum erosion rates in the range of 300–700?V are found not to exceed 10{sup ?2}?mm/kh. Such rates are ?3 orders of magnitude less than those observed in the unshielded version of the same thruster at 300?V. At 9?kW and 800?V, saturation of the magnetic circuit did not allow for precisely the same magnetic shielding topology as that employed during the 6-kW operation since this thruster was not designed to operate at this condition. Consequently, the maximum erosion rate at the inner wall is found to be ?1 order of magnitude higher (?10{sup ?1}?mm/kh) than that at 6?kW. At the outer wall, the ion energy is found to be below the sputtering yield threshold so no measurable erosion is expected.

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

    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:FinancingPetroleum12,ExecutiveFinancingR Walls - Building America Topa High BindingVoltage

  10. ME/AE/CompE/EE 378 Mechatronics VOLTAGE AMPLIFIER LABORATORY

    E-Print Network [OSTI]

    Landers, Robert G.

    be labeled and contain units, and diagrams must be drawn with a software package. Table 1: Voltage Amplifier

  11. 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.

  12. Thermally-induced voltage alteration for integrated circuit analysis

    DOE Patents [OSTI]

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

    2000-01-01

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

  13. Thermally-induced voltage alteration for analysis of microelectromechanical devices

    DOE Patents [OSTI]

    Walraven, Jeremy A. (Albuquerque, NM); Cole, Jr., Edward I. (Albuquerque, NM)

    2002-01-01

    A thermally-induced voltage alteration (TIVA) apparatus and method are disclosed for analyzing a microelectromechanical (MEM) device with or without on-board integrated circuitry. One embodiment of the TIVA apparatus uses constant-current biasing of the MEM device while scanning a focused laser beam over electrically-active members therein to produce localized heating which alters the power demand of the MEM device and thereby changes the voltage of the constant-current source. This changing voltage of the constant-current source can be measured and used in combination with the position of the focused and scanned laser beam to generate an image of any short-circuit defects in the MEM device (e.g. due to stiction or fabrication defects). In another embodiment of the TIVA apparatus, an image can be generated directly from a thermoelectric potential produced by localized laser heating at the location of any short-circuit defects in the MEM device, without any need for supplying power to the MEM device. The TIVA apparatus can be formed, in part, from a scanning optical microscope, and has applications for qualification testing or failure analysis of MEM devices.

  14. Performance Characteristics Of The Reduced Common Mode Voltage Near State PWM Method

    E-Print Network [OSTI]

    Hava, Ahmet

    induction and permanent magnet machines are driven through three-phase Voltage Source Inverters (VSI) which to generate the required output voltages. Conventional Continuous PWM (CPWM) methods such as Space Vector PWM with rather smaller IGBT gate resistances), and high DC bus voltage levels, the CMVs generated result

  15. 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

  16. Re-Dispatching Generation to Increase Power System Security Margin and Support Low Voltage Bus

    E-Print Network [OSTI]

    Re-Dispatching Generation to Increase Power System Security Margin and Support Low Voltage Bus by re-dispatching generator outputs, using a normal vector found at a voltage collapse boundary or a low voltage boundary (LVB). This method uses the normal vector as an indicator to change the generation

  17. Voltage Utilization in Model Predictive Control for Michael Leuer, Joachim Bocker

    E-Print Network [OSTI]

    Noé, Reinhold

    Voltage Utilization in Model Predictive Control for IPMSM Michael Leuer, Joachim B¨ocker Power (IPMSM). Besides the good dynamics, the utilization of the DC link voltage is important for these motor types. Since the MPC is able to utilize the available DC link voltage optimally, the MPC is superior

  18. Energy Minimization Using Multiple Supply Voltages Jui-Ming Chang and Massoud Pedram

    E-Print Network [OSTI]

    Pedram, Massoud

    Energy Minimization Using Multiple Supply Voltages Jui-Ming Chang and Massoud Pedram Department and energy costs of these level shifters must be taken into account when comparing a multiple-supply voltage a dynamic programming technique for solv- ing the multiple supply voltage scheduling problem in both non

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

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

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

  20. Scaling Analysis of On-Chip Power Grid Voltage Variations in Nanometer Scale ULSI

    E-Print Network [OSTI]

    Pedram, Massoud

    Scaling Analysis of On-Chip Power Grid Voltage Variations in Nanometer Scale ULSI AMIR H. AJAMI, 1 be insufficient to limit the voltage fluctuations over the power grid for future technologies. It is also shown voltage drop in the power grid may result in a functional failure in dynamic logic and a timing violation

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

    E-Print Network [OSTI]

    Najm, Farid N.

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

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

    E-Print Network [OSTI]

    Najm, Farid N.

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

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

    E-Print Network [OSTI]

    Najm, Farid N.

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

  4. PreDVS: Preemptive Dynamic Voltage Scaling for Real-time Systems using Approximation Scheme

    E-Print Network [OSTI]

    Mishra, Prabhat

    , dynamic voltage scal- ing, approximation algorithm 1. INTRODUCTION Energy conservation has been the main to save energy is that linear reduction in the supply voltage leads to approximately linear slow downPreDVS: Preemptive Dynamic Voltage Scaling for Real-time Systems using Approximation Scheme Weixun

  5. Tangle: Route-Oriented Dynamic Voltage Minimization for Variation-Afflicted, Energy-

    E-Print Network [OSTI]

    Torrellas, Josep

    Voltage EnergyperOperation 1.0V #12;Low-Voltage Operation Vdd reduction is one of the best leversTangle: Route-Oriented Dynamic Voltage Minimization for Variation-Afflicted, Energy- Efficient On for energy efficiency o Big reduction in dynamic power; also reduction in static power New technologies

  6. Leakage-Aware Energy Minimization using Dynamic Voltage Scaling and Cache

    E-Print Network [OSTI]

    Mishra, Prabhat

    takes the advantage of the fact that linear reduction in the supply voltage can quadrati- cally reduceLeakage-Aware Energy Minimization using Dynamic Voltage Scaling and Cache Reconfiguration in Real are widely used to improve energy efficiency as well as overall performance. Dynamic voltage scaling (DVS

  7. Solid State AC Motor Drives - Conservation Perspectives 

    E-Print Network [OSTI]

    Mohan, N.; Ferraro, R. J.

    1982-01-01

    Variable Frequency Solid-State Inverters: can control the speed of ac motors by producing adjustable frequency ac voltage, with an enormous potential for energy conservation in pumps and air handling systems. 3. Other Variable Frequency Drives: include...

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

    SciTech Connect (OSTI)

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

    2009-11-15

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

  9. Frequency mixing crystal

    DOE Patents [OSTI]

    Ebbers, Christopher A. (Livermore, CA); Davis, Laura E. (Manteca, CA); Webb, Mark (Salida, CA)

    1992-01-01

    In a laser system for converting infrared laser light waves to visible light comprising a source of infrared laser light waves and means of harmoic generation associated therewith for production of light waves at integral multiples of the frequency of the original wave, the improvement of said means of harmonic generation comprising a crystal having the chemical formula X.sub.2 Y(NO.sub.3).sub.5 .multidot.2 nZ.sub.2 o wherein X is selected from the group consisting of Li, Na, K, Rb, Cs, and Tl; Y is selected from the group consisting of Sc, Y, La, Ce, Nd, Pr, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Al, Ga, and In; Z is selected from the group consisting of H and D; and n ranges from 0 to 4.

  10. Frequency doubling crystals

    DOE Patents [OSTI]

    Wang, Francis (Danville, CA); Velsko, Stephan P. (Livermore, CA)

    1989-01-01

    A systematic approach to the production of frequency conversion crystals is described in which a chiral molecule has attached to it a "harmonic generating unit" which contributes to the noncentrosymmetry of the molecule. Certain preferred embodiments of such harmonic generating units include carboxylate, guanadyly and imidazolyl units. Certain preferred crystals include L-arginine fluoride, deuterated L-arginine fluoride, L-arginine chloride monohydrate, L-arginine acetate, dithallium tartrate, ammonium N-acetyl valine, N-acetyl tyrosine and N-acetyl hydroxyproline. Chemical modifications of the chiral molecule, such as deuteration, halogenation and controlled counterion substitution are available to adapt the dispersive properties of a crystal in a particular wavelength region.

  11. Flying radio frequency undulator

    SciTech Connect (OSTI)

    Kuzikov, S. V.; Vikharev, A. A. [Institute of Applied Physics, Russian Academy of Sciences, 46 Ulyanov St., Nizhny Novgorod 603950 (Russian Federation); Savilov, A. V. [Institute of Applied Physics, Russian Academy of Sciences, 46 Ulyanov St., Nizhny Novgorod 603950 (Russian Federation); Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod (Russian Federation)

    2014-07-21

    A concept for the room-temperature rf undulator, designed to produce coherent X-ray radiation by means of a relatively low-energy electron beam and pulsed mm-wavelength radiation, is proposed. The “flying” undulator is a high-power short rf pulse co-propagating together with a relativistic electron bunch in a helically corrugated waveguide. The electrons wiggle in the rf field of the ?1st spatial harmonic with the phase velocity directed in the opposite direction in respect to the bunch velocity, so that particles can irradiate high-frequency Compton's photons. A high group velocity (close to the speed of light) ensures long cooperative motion of the particles and the co-propagating rf pulse.

  12. High frequency nanotube oscillator

    DOE Patents [OSTI]

    Peng, Haibing (Houston, TX); Zettl, Alexander K. (Kensington, TX)

    2012-02-21

    A tunable nanostructure such as a nanotube is used to make an electromechanical oscillator. The mechanically oscillating nanotube can be provided with inertial clamps in the form of metal beads. The metal beads serve to clamp the nanotube so that the fundamental resonance frequency is in the microwave range, i.e., greater than at least 1 GHz, and up to 4 GHz and beyond. An electric current can be run through the nanotube to cause the metal beads to move along the nanotube and changing the length of the intervening nanotube segments. The oscillator can operate at ambient temperature and in air without significant loss of resonance quality. The nanotube is can be fabricated in a semiconductor style process and the device can be provided with source, drain, and gate electrodes, which may be connected to appropriate circuitry for driving and measuring the oscillation. Novel driving and measuring circuits are also disclosed.

  13. Performance of the OVP/UVP and OFP/UFP method with voltage and frequency dependent loads

    E-Print Network [OSTI]

    Kirtley, James L., Jr.

    In previous literature, constant RLC loads were assumed to impose, on the islanding detection method, the hardest detectable case. For this reason, distributed-generation (DG) islanding studies are usually analyzed and ...

  14. Low power low-density parity-checking (ldpc) codes decoder design using dynamic voltage and frequency scaling 

    E-Print Network [OSTI]

    Wang, Weihuang

    2009-05-15

    This thesis presents a low-power LDPC decoder design based on speculative scheduling of energy necessary to decode dynamically varying data frame in both block-fading channels and general AWGN channels. A model of a ...

  15. Fluidic, Solid-State, and Hybrid Reconfiguration Techniques in a Frequency and Polarization Reconfigurable Antenna 

    E-Print Network [OSTI]

    Barrera, Joel Daniel

    2014-12-16

    Reconfigurable Antenna ISM Industrial, scientific, and medical I-V Current and voltage MEMS Microelectromechanical systems MS Microstrip PDMS Polydimethylsiloxane PIN P-type, intrinsic, N-type PN P-type and N-type PRA Polarization Reconfigurable Antenna...-8], and RF-MEMS [9-11] on or near the antenna surface. In [1], the authors achieve a widely frequency agile microstrip patch antenna by integrating three pairs of varactor diodes along with a broadband differential feeding scheme. Furthermore, the authors...

  16. Low-frequency RF Coupling To Unconventional (Fat Unbalanced) Dipoles

    SciTech Connect (OSTI)

    Ong, M M; Brown, C G; Perkins, M P; Speer, R D; Javedani, J B

    2010-12-07

    The report explains radio frequency (RF) coupling to unconventional dipole antennas. Normal dipoles have thin equal length arms that operate at maximum efficiency around resonance frequencies. In some applications like high-explosive (HE) safety analysis, structures similar to dipoles with ''fat'' unequal length arms must be evaluated for indirect-lightning effects. An example is shown where a metal drum-shaped container with HE forms one arm and the detonator cable acts as the other. Even if the HE is in a facility converted into a ''Faraday cage'', a lightning strike to the facility could still produce electric fields inside. The detonator cable concentrates the electric field and carries the energy into the detonator, potentially creating a hazard. This electromagnetic (EM) field coupling of lightning energy is the indirect effect of a lightning strike. In practice, ''Faraday cages'' are formed by the rebar of the concrete facilities. The individual rebar rods in the roof, walls and floor are normally electrically connected because of the construction technique of using metal wire to tie the pieces together. There are two additional requirements for a good cage. (1) The roof-wall joint and the wall-floor joint must be electrically attached. (2) All metallic penetrations into the facility must also be electrically connected to the rebar. In this report, it is assumed that these conditions have been met, and there is no arcing in the facility structure. Many types of detonators have metal ''cups'' that contain the explosives and thin electrical initiating wires, called bridge wires mounted between two pins. The pins are connected to the detonator cable. The area of concern is between the pins supporting the bridge wire and the metal cup forming the outside of the detonator. Detonator cables usually have two wires, and in this example, both wires generated the same voltage at the detonator bridge wire. This is called the common-mode voltage. The explosive component inside a detonator is relatively sensitive, and any electrical arc is a concern. In a safety analysis, the pin-to-cup voltage, i.e., detonator voltage, must be calculated to decide if an arc will form. If the electric field is known, the voltage between any two points is simply the integral of the field along a line between the points. Eq. 1.1. For simplicity, it is assumed that the electric field and dipole elements are aligned. Calculating the induced detonator voltage is more complex because of the field concentration caused by metal components. If the detonator cup is not electrically connected to the metal HE container, the portion of the voltage generated by the dipole at the detonator will divide between the container-to-cup and cup-to-pin gaps. The gap voltages are determined by their capacitances. As a simplification, it will be assumed the cup is electrically attached, short circuited, to the HE container. The electrical field in the pin-to-cup area is determined by the field near the dipole, the length of the dipole, the shape of the arms, and the orientation of the arms. Given the characteristics of a lightning strike and the inductance of the facility, the electric fields in the ''Faraday cage'' can be calculated. The important parameters for determining the voltage in an empty facility are the inductance of the rebars and the rate of change of the current, Eq. 1.3. The internal electric fields are directly related to the facility voltages, however, the electric fields in the pin-to-cup space is much higher than the facility fields because the antenna will concentrate the fields covered by the arms. Because the lightning current rise-time is different for every strike, the maximum electric field and the induced detonator voltage should be described by probability distributions. For pedantic purposes, the peak field in the simulations will be simply set to 1 V/m. Lightning induced detonator voltages can be calculated by scaling up with the facility fields. Any metal object around the explosives, such as a work stand, will also distort the electric

  17. A Surprising Clarification of the Mechanism of Ion-channel Voltage-Gating

    E-Print Network [OSTI]

    Ashok Palaniappan

    2011-04-20

    An intense controversy has surrounded the mechanism of voltage-gating in ion channels. We interpreted the two leading models of voltage-gating with respect to the thermodynamic energetics of membrane insertion of the voltage-sensing 'module' from a comprehensive set of potassium channels. KvAP is an archaeal voltage-gated potassium channel whose x-ray structure was the basis for determining the general mechanism of voltage-gating. The free energy of membrane insertion of the KvAP voltage sensor was revealed to be a single outlier. This was due to its unusual sequence that facilitated large gating movements in its native lipid membrane. This degree of free energy was the least typical of the other voltage sensors, including the Shaker potassium channel. We inferred that the two leading models of voltage-gating referred to alternative mechanisms of voltage-gating: each is applicable to an independent set of ion channels. The large motion of the voltage-sensor during gating proposed by the KvAP-paddle model of gating is unlikely to be mirrored by the majority of ion channels whose voltage sensors are not located at the membrane-cytoplasm interface in the channel closed state.

  18. Variable Refrigerant Flow HVAC 

    E-Print Network [OSTI]

    Jones, S.

    2013-01-01

    Variable refrigerant flow technology HVAC CATEE 2013 San Antonio, TX ESL-KT-13-12-33 CATEE 2013: Clean Air Through Energy Efficiency Conference, San Antonio, Texas Dec. 16-18 What is the acronym VRF? ? Variable Refrigerant Flow Operates like a... heat pump utilizing VFD Inverter Compressors and LEV’s Unlike conventional commercial and residential HVAC systems in the USA The predominate method of cooling and heating in the world ESL-KT-13-12-33 CATEE 2013: Clean Air Through Energy Efficiency...

  19. Long-Term Wind Power Variability

    SciTech Connect (OSTI)

    Wan, Y. H.

    2012-01-01

    The National Renewable Energy Laboratory started collecting wind power data from large commercial wind power plants (WPPs) in southwest Minnesota with dedicated dataloggers and communication links in the spring of 2000. Over the years, additional WPPs in other areas were added to and removed from the data collection effort. The longest data stream of actual wind plant output is more than 10 years. The resulting data have been used to analyze wind power fluctuations, frequency distribution of changes, the effects of spatial diversity, and wind power ancillary services. This report uses the multi-year wind power data to examine long-term wind power variability.

  20. Light-induced voltage alteration for integrated circuit analysis

    DOE Patents [OSTI]

    Cole, E.I. Jr.; Soden, J.M.

    1995-07-04

    An apparatus and method are described for analyzing an integrated circuit (IC). The invention uses a focused light beam that is scanned over a surface of the IC to generate a light-induced voltage alteration (LIVA) signal for analysis of the IC. The LIVA signal may be used to generate an image of the IC showing the location of any defects in the IC; and it may be further used to image and control the logic states of the IC. The invention has uses for IC failure analysis, for the development of ICs, for production-line inspection of ICs, and for qualification of ICs. 18 figs.

  1. 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.

  2. Self-monitoring high voltage transmission line suspension insulator

    DOE Patents [OSTI]

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

    1981-01-01

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

  3. Mechanisms limiting open circuit voltage in silicon solar cells

    SciTech Connect (OSTI)

    Spitzer, M.B.; Keavney, C.J.; Lindholm, F.A.; Nevgroschel, A.; Tobin, S.P.

    1984-05-01

    This paper reports the results of research on mechanisms limiting open circuit voltage in conventional p/n junction silicon solar cells, with a view toward both the understanding of various heavy-doping effects and the achievement of high conversion efficiency. Experimental and theoretical studies have been conducted in order to correlate heavy-doping effects to actual solar cell performance. The experiments have utilized a variety of emitter configurations with various doping concentrations in order to emphasize a number of concentration-dependent mechanisms. The theoretical modeling addresses the determination of both recombination velocity at the passivated front surface and effects of recombination at the front ohmic contact.

  4. Outdoor PV Module Degradation of Current-Voltage Parameters: Preprint

    SciTech Connect (OSTI)

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

    2012-04-01

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

  5. Induction of nuclear fission by high-voltage application

    E-Print Network [OSTI]

    Hirokazu Maruyama

    2007-11-20

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

  6. IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS--I: REGULAR PAPERS, VOL. 55, NO. 6, JULY 2008 1751 Dual Low-Voltage IC Design for High-Voltage

    E-Print Network [OSTI]

    and low side gate drivers are required in most switching power converters to provide on/off control Low-Voltage IC Design for High-Voltage Floating Gate Drives Yan Yin, Member, IEEE, and Regan Zane, Senior Member, IEEE Abstract--An integrated circuit (IC) design for low and high side gate drive in high

  7. Variable thrust cartridge

    DOE Patents [OSTI]

    Taleyarkhan, Rusi P. (Knoxville, TN)

    2000-11-07

    The present invention is a variable thrust cartridge comprising a water-molten aluminum reaction chamber from which a slug is propelled. The cartridge comprises a firing system that initiates a controlled explosion from the reaction chamber. The explosive force provides a thrust to a slug, preferably contained within the cartridge.

  8. Effective switching frequency multiplier inverter

    DOE Patents [OSTI]

    Su, Gui-Jia (Oak Ridge, TN); Peng, Fang Z. (Okemos, MI)

    2007-08-07

    A switching frequency multiplier inverter for low inductance machines that uses parallel connection of switches and each switch is independently controlled according to a pulse width modulation scheme. The effective switching frequency is multiplied by the number of switches connected in parallel while each individual switch operates within its limit of switching frequency. This technique can also be used for other power converters such as DC/DC, AC/DC converters.

  9. Bi-directional power control system for voltage converter

    DOE Patents [OSTI]

    Garrigan, N.R.; King, R.D.; Schwartz, J.E.

    1999-05-11

    A control system for a voltage converter includes: a power comparator for comparing a power signal on input terminals of the converter with a commanded power signal and producing a power comparison signal; a power regulator for transforming the power comparison signal to a commanded current signal; a current comparator for comparing the commanded current signal with a measured current signal on output terminals of the converter and producing a current comparison signal; a current regulator for transforming the current comparison signal to a pulse width modulator (PWM) duty cycle command signal; and a PWM for using the PWM duty cycle command signal to control electrical switches of the converter. The control system may further include: a command multiplier for converting a voltage signal across the output terminals of the converter to a gain signal having a value between zero (0) and unity (1), and a power multiplier for multiplying the commanded power signal by the gain signal to provide a limited commanded power signal, wherein power comparator compares the limited commanded power signal with the power signal on the input terminals. 10 figs.

  10. Bi-directional power control system for voltage converter

    DOE Patents [OSTI]

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

    1999-01-01

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

  11. Commercialization of Medium Voltage HTS Triax TM Cable Systems

    SciTech Connect (OSTI)

    Knoll, David

    2012-12-31

    The original project scope that was established in 2007 aimed to install a 1,700 meter (1.1 mile) medium voltage HTS Triax{TM} cable system into the utility grid in New Orleans, LA. In 2010, however, the utility partner withdrew from the project, so the 1,700 meter cable installation was cancelled and the scope of work was reduced. The work then concentrated on the specific barriers to commercialization of HTS cable technology. The modified scope included long-length HTS cable design and testing, high voltage factory test development, optimized cooling system development, and HTS cable life-cycle analysis. In 2012, Southwire again analyzed the market for HTS cables and deemed the near term market acceptance to be low. The scope of work was further reduced to the completion of tasks already started and to testing of the existing HTS cable system in Columbus, OH. The work completed under the project included: • Long-length cable modeling and analysis • HTS wire evaluation and testing • Cable testing for AC losses • Optimized cooling system design • Life cycle testing of the HTS cable in Columbus, OH • Project management. The 200 meter long HTS Triax{TM} cable in Columbus, OH was incorporated into the project under the initial scope changes as a test bed for life cycle testing as well as the site for an optimized HTS cable cooling system. The Columbus cable utilizes the HTS TriaxTM design, so it provided an economical tool for these of the project tasks.

  12. Atmospheric pressure plasma jet with high-voltage power supply based on piezoelectric transformer

    SciTech Connect (OSTI)

    Babij, Micha?; Kowalski, Zbigniew W. Nitsch, Karol; Gotszalk, Teodor; Silberring, Jerzy

    2014-05-15

    The dielectric barrier discharge plasma jet, an example of the nonthermal atmospheric pressure plasma jet (APPJ), generates low-temperature plasmas that are suitable for the atomization of volatile species and can also be served as an ionization source for ambient mass and ion mobility spectrometry. A new design of APPJ for mass spectrometry has been built in our group. In these plasma sources magnetic transformers (MTs) and inductors are typically used in power supplies but they present several drawbacks that are even more evident when dealing with high-voltage normally used in APPJs. To overcome these disadvantages, high frequency generators with the absence of MT are proposed in the literature. However, in the case of miniaturized APPJs these conventional power converters, built of ferromagnetic cores and inductors or by means of LC resonant tank circuits, are not so useful as piezoelectric transformer (PT) based power converters due to bulky components and small efficiency. We made and examined a novel atmospheric pressure plasma jet with PT supplier served as ionization source for ambient mass spectrometry, and especially mobile spectrometry where miniaturization, integration of components, and clean plasma are required. The objective of this paper is to describe the concept, design, and implementation of this miniaturized piezoelectric transformer-based atmospheric pressure plasma jet.

  13. Acoustic resonance frequency locked photoacoustic spectrometer

    DOE Patents [OSTI]

    Pilgrim, Jeffrey S.; Bomse, David S.; Silver, Joel A.

    2003-09-09

    A photoacoustic spectroscopy method and apparatus for maintaining an acoustic source frequency on a sample cell resonance frequency comprising: providing an acoustic source to the sample cell, the acoustic source having a source frequency; repeatedly and continuously sweeping the source frequency across the resonance frequency at a sweep rate; and employing an odd-harmonic of the source frequency sweep rate to maintain the source frequency sweep centered on the resonance frequency.

  14. 96 IEEE POWER ELECTRONICS LETTERS, VOL. 2, NO. 3, SEPTEMBER 2004 Low-Input-Voltage, Low-Power Boost

    E-Print Network [OSTI]

    Chapman, Patrick

    to connect varying voltage to the fixed voltage load with high efficiency. Individual fuel cells naturally are investigated when a low input voltage is used. Low- input-voltage sources include single fuel cells, single solar cells, and thermoelectric devices. The primary context is interfacing single micro fuel cells

  15. DECENTRALIZED CONTROL ARCHITECTURE FOR COUPLING MICROGRIDS INTO DISTRIBUTION NETWORKS 1 Task 1: Coupling Low-Voltage Microgrids into

    E-Print Network [OSTI]

    Lemmon, Michael

    DECENTRALIZED CONTROL ARCHITECTURE FOR COUPLING MICROGRIDS INTO DISTRIBUTION NETWORKS 1 Task 1: Coupling Low-Voltage Microgrids into Mid-Voltage Distribution Systems Zhao Wang, Student Member, IEEE-voltage (LV) microgrids. At the same time, reactive power is dispatched coordinatively so that voltage

  16. Abstract -This paper introduces techniques for power efficient design of power delivery network in multiple voltage-island

    E-Print Network [OSTI]

    Pedram, Massoud

    in multiple voltage-island System-on-Chip (SoC) designs. The first technique is targeted to SoC designs network, voltage regulator, DC-DC converter, energy efficiency, voltage island, system-on-chip I island approach [3]. In these systems, it is required that the PDN delivers power at appropriate voltage

  17. Variable depth core sampler

    DOE Patents [OSTI]

    Bourgeois, P.M.; Reger, R.J.

    1996-02-20

    A variable depth core sampler apparatus is described comprising a first circular hole saw member, having longitudinal sections that collapses to form a point and capture a sample, and a second circular hole saw member residing inside said first hole saw member to support the longitudinal sections of said first hole saw member and prevent them from collapsing to form a point. The second hole saw member may be raised and lowered inside said first hole saw member. 7 figs.

  18. Variable laser attenuator

    DOE Patents [OSTI]

    Foltyn, S.R.

    1987-05-29

    The disclosure relates to low loss, high power variable attenuators comprising one or more transmissive and/or reflective multilayer dielectric filters. The attenuator is particularly suitable to use with unpolarized lasers such as excimer lasers. Beam attenuation is a function of beam polarization and the angle of incidence between the beam and the filter and is controlled by adjusting the angle of incidence the beam makes to the filter or filters. Filters are selected in accordance with beam wavelength. 9 figs.

  19. Variable depth core sampler

    DOE Patents [OSTI]

    Bourgeois, Peter M. (Hamburg, NY); Reger, Robert J. (Grand Island, NY)

    1996-01-01

    A variable depth core sampler apparatus comprising a first circular hole saw member, having longitudinal sections that collapses to form a point and capture a sample, and a second circular hole saw member residing inside said first hole saw member to support the longitudinal sections of said first hole saw member and prevent them from collapsing to form a point. The second hole saw member may be raised and lowered inside said first hole saw member.

  20. Transparency in nonlinear frequency conversion

    E-Print Network [OSTI]

    Longhi, Stefano

    2015-01-01

    Suppression of wave scattering and the realization of transparency effects in engineered optical media and surfaces have attracted great attention in the past recent years. In this work the problem of transparency is considered for optical wave propagation in a nonlinear dielectric medium with second-order $\\chi^{(2)}$ susceptibility. Because of nonlinear interaction, a reference signal wave at carrier frequency $\\omega_1$ can exchange power, thus being amplified or attenuated,when phase matching conditions are satisfied and frequency conversion takes place. Therefore, rather generally the medium is not transparent to the signal wave because of 'scattering' in the frequency domain. Here we show that broadband transparency, corresponding to the full absence of frequency conversion in spite of phase matching, can be observed for the signal wave in the process of sum frequency generation whenever the effective susceptibility $\\chi^{(2)}$ along the nonlinear medium is tailored following a suitable spatial apodiza...

  1. Design, development, and acceleration trials of radio-frequency quadrupole

    SciTech Connect (OSTI)

    Rao, S. V. L. S. Jain, Piyush; Pande, Rajni; Roy, Shweta; Mathew, Jose V.; Kumar, Rajesh; Pande, Manjiri; Krishnagopal, S.; Gupta, S. K.; Singh, P.

    2014-04-15

    A deuteron radio frequency quadrupole (RFQ) accelerator has been designed, fabricated, and tested at BARC, which will be used for neutron generation. The RFQ operates at a frequency of 350 MHz and needs an inter-vane voltage of 44 kV to accelerate the deuteron beam to 400 keV within a length of 1.03 m. The error analysis shows that the offset of two opposite vanes in the same direction by 100 ?m leads to a change in resonant frequency by 1.3 MHz and a significant change of fields in the quadrants (?±40% with respect to average field). From the 3D analysis, we have observed that the unwanted dipole mode frequencies are very near to the quadrupole mode frequency which will make structure sensitive to the perturbations. In order to move the dipole modes away from the quadrupole modes, we have used the dipole stabilizer rods. The 5 wire transmission line theory was used to study the perturbative analysis of the RFQ and based on this a computer program has been written to tune the cavity to get required field distribution. Based on these studies, a 1.03 m long RFQ made of OFE copper has been fabricated and tested. Even though the RFQ was designed for deuteron (D{sup +}) beam, we tested it by accelerating both the proton (H{sup +}) and D{sup +} beams. The RFQ was operated in pulsed mode and accelerated both H{sup +} and D{sup +} beams to designed values of 200 and 400 keV, respectively. The measured parameters are in good agreement with the designed values validating our simulations and fabrication processes. In this paper, simulations, RF measurements, and beam commissioning results are presented.

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

    SciTech Connect (OSTI)

    Baone, Chaitanya A; Xu, Yan; Kueck, John D

    2010-01-01

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

  3. Understanding and Improving High Voltage Vacuum Insulators for Microsecond Pulses

    SciTech Connect (OSTI)

    Javedani, J B; Goerz, D A; Houck, T L; Lauer, E J; Speer, R D; Tully, L K; Vogtlin, G E; White, A D

    2007-03-05

    High voltage insulation is one of the main areas of pulsed power research and development, and dielectric breakdown is usually the limiting factor in attaining the highest possible performance in pulsed power devices. For many applications the delivery of pulsed power into a vacuum region is the most critical aspect of operation. The surface of an insulator exposed to vacuum can fail electrically at an applied field more than an order or magnitude below the bulk dielectric strength of the insulator. This mode of breakdown, called surface flashover, imposes serious limitations on the power flow into a vacuum region. This is especially troublesome for applications where high voltage conditioning of the insulator and electrodes is not practical and for applications where relatively long pulses, on the order of several microseconds, are required. The goal of this project is to establish a sound fundamental understanding of the mechanisms that lead to surface flashover, and then evaluate the most promising techniques to improve vacuum insulators and enable high voltage operation at stress levels near the intrinsic bulk breakdown limits of the material. The approach we proposed and followed was to develop this understanding through a combination of theoretical and computation methods coupled with experiments to validate and quantify expected behaviors. In this report we summarize our modeling and simulation efforts, theoretical studies, and experimental investigations. The computational work began by exploring the limits of commercially available codes and demonstrating methods to examine field enhancements and defect mechanisms at microscopic levels. Plasma simulations with particle codes used in conjunction with circuit models of the experimental apparatus enabled comparisons with experimental measurements. The large scale plasma (LSP) particle-in-cell (PIC) code was run on multiprocessor platforms and used to simulate expanding plasma conditions in vacuum gap regions. Algorithms were incorporated into LSP to handle secondary electron emission from dielectric materials to enable detailed simulations of flashover phenomenon. Theoretical studies were focused on explaining a possible mechanism for anode initiated surface flashover that involves an electron avalanche process starting near the anode, not a mechanism involving bulk dielectric breakdown. Experiments were performed in Engineering's Pulsed Power Lab using an available 100-kV, 10-{micro}s pulse generator and vacuum chamber. The initial experiments were done with polyethylene insulator material in the shape of a truncated cone cut at +45{sup o} angle between flat electrodes with a gap of 1.0 cm. The insulator was sized so there were no flashovers or breakdowns under nominal operating conditions. Insulator flashover or gap closure was induced by introducing a plasma source, a tuft of velvet, in proximity to the insulator or electrode.

  4. Role of Climate Variability in Modulating the Surface Water and Groundwater Interaction

    E-Print Network [OSTI]

    Arumugam, Sankar

    levels with El Niño/ Southern Oscillation (ENSO) index, NINO3.4, shows that interannual variability between JAS groundwater levels and JAS NINO3.4 is not statistically significant. Precipitation forecasts exists on the association between low-frequency climatic variability [e.g., El Niño/Southern Oscillation

  5. Design and Implementation of Switching Voltage Integrated Circuits Based on Sliding Mode Control 

    E-Print Network [OSTI]

    Rojas Gonzalez, Miguel Angel

    2010-10-12

    .S. (Honors), ITESM Campus Toluca, Mexico Chair of Advisory Committee: Dr. Edgar S?anchez-Sinencio The need for high performance circuits in systems with low-voltage and low-power requirements has exponentially increased during the few last years due... measurements of the dual-output buck voltage regulator for (a) Medium load condition and (b) High load condition : : : 207 132 (a) Power efficiency measurements of the dual-output buck voltage versus both output currents and (b) Top view...

  6. Voltage/Pitch Control for Maximization and Regulation of Active/Reactive Powers in Wind Turbines with Uncertainties

    E-Print Network [OSTI]

    Guo, Yi; Jiang, John N; Tang, Choon Yik; Ramakumar, Rama G

    2010-01-01

    This paper addresses the problem of controlling a variable-speed wind turbine with a Doubly Fed Induction Generator (DFIG), modeled as an electromechanically-coupled nonlinear system with rotor voltages and blade pitch angle as its inputs, active and reactive powers as its outputs, and most of the aerodynamic and mechanical parameters as its uncertainties. Using a blend of linear and nonlinear control strategies (including feedback linearization, pole placement, uncertainty estimation, and gradient-based potential function minimization) as well as time-scale separation in the dynamics, we develop a controller that is capable of maximizing the active power in the Maximum Power Tracking (MPT) mode, regulating the active power in the Power Regulation (PR) mode, seamlessly switching between the two modes, and simultaneously adjusting the reactive power to achieve a desired power factor. The controller consists of four cascaded components, uses realistic feedback signals, and operates without knowledge of the C_p-...

  7. Probabilistic Vulnerability Assessment Based on Power Flow and Voltage Distribution

    SciTech Connect (OSTI)

    Ma, Jian; Huang, Zhenyu; Wong, Pak C.; Ferryman, Thomas A.

    2010-04-30

    Risk assessment of large scale power systems has been an important problem in power system reliability study. Probabilistic technique provides a powerful tool to solve the task. In this paper, we present the results of a study on probabilistic vulnerability assessment on WECC system. Cumulant based expansion method is applied to obtain the probabilistic distribution function (PDF) and cumulative distribution function (CDF) of power flows on transmission lines and voltage. Overall risk index based on the system vulnerability analysis is calculated using the WECC system. The simulation results based on WECC system is used to demonstrate the effectiveness of the method. The methodology can be applied to the risk analysis on large scale power systems.

  8. Monolithic high voltage nonlinear transmission line fabrication process

    DOE Patents [OSTI]

    Cooper, G.A.

    1994-10-04

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

  9. Curing system for high voltage cross linked cables

    DOE Patents [OSTI]

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

    1978-01-01

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

  10. High-voltage atmospheric breakdown across intervening rutile dielectrics.

    SciTech Connect (OSTI)

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

    2013-09-01

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

  11. High voltage design structure for high temperature superconducting device

    DOE Patents [OSTI]

    Tekletsadik, Kasegn D. (Rexford, NY)

    2008-05-20

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

  12. 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.

  13. System and method for floating-substrate passive voltage contrast

    DOE Patents [OSTI]

    Jenkins, Mark W. (Albuquerque, NM); Cole, Jr., Edward I. (Albuquerque, NM); Tangyunyong, Paiboon (Albuquerque, NM); Soden, Jerry M. (Placitas, NM); Walraven, Jeremy A. (Albuquerque, NM); Pimentel, Alejandro A. (Albuquerque, NM)

    2009-04-28

    A passive voltage contrast (PVC) system and method are disclosed for analyzing ICs to locate defects and failure mechanisms. During analysis a device side of a semiconductor die containing the IC is maintained in an electrically-floating condition without any ground electrical connection while a charged particle beam is scanned over the device side. Secondary particle emission from the device side of the IC is detected to form an image of device features, including electrical vias connected to transistor gates or to other structures in the IC. A difference in image contrast allows the defects or failure mechanisms be pinpointed. Varying the scan rate can, in some instances, produce an image reversal to facilitate precisely locating the defects or failure mechanisms in the IC. The system and method are useful for failure analysis of ICs formed on substrates (e.g. bulk semiconductor substrates and SOI substrates) and other types of structures.

  14. Low voltage secondary network cable reliability study. Final report

    SciTech Connect (OSTI)

    1995-05-01

    In an attempt to find clues to the causes of manhole fires and explosions, researchers removed several aged low voltage network cables from service on the United Illuminating Company system. Examination of their physical, chemical, and electrical properties indicated that any deterioration of the cables that had occurred during their approximately 35 year service life was minor and did not affect reliability for continued service. Cables were found to have retained excellent properties despite their long age in service. For example, AC breakdown strength, dissipation factor, and percent elongation were all satisfactory. Insulation was coherent, not brittle; and the jackets did not crack or craze on bending. The tested cables compare favorably, physically and electrically, with non-jacketed rubber cables presently in service.

  15. Image-line voltage controlled oscillators and grating antennas 

    E-Print Network [OSTI]

    Kirk, Alexander MacDonald

    1991-01-01

    Chair of Advisory Committee: Dr. Kai Chang A novel active antenna is proposed with an image-line construction. An image-line Gunn diode oscillator utilizing a cap resonator, for frequency stability, is the source module for the antenna. A varactor... is added to the source module for frequency tuning. Combining Gunn diode bias and varactor tuning, 2 percent electronic tuning bandwidth in the X-band has been achieved. The source module is an integral part of an image-line periodic grating antenna...

  16. Experimental Validation of Voltage-Based State-of-Charge Algorithm for Power Batteries

    E-Print Network [OSTI]

    Jia, Zhuo

    2013-01-01

    Control of Lithium-Ion Batteries”, Control Systems, IEEE,is one type of Lithium-Ion batteries with voltage around

  17. Dynamic voltage-current characteristics for a water jet plasma arc

    SciTech Connect (OSTI)

    Yang Jiaxiang; Lan Sheng; Xu Zuoming

    2008-05-05

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

  18. Cellular/Molecular Fast-Activating Voltage-and Calcium-Dependent Potassium

    E-Print Network [OSTI]

    Cellular/Molecular Fast-Activating Voltage- and Calcium-Dependent Potassium (BK) Conductance present in the cellular membrane. Experimental and computational approaches have revealed the dynamic

  19. State-of-the-art Fuel Cell Voltage Durability Status: 2015 Composite Data Products

    SciTech Connect (OSTI)

    Kurtz, Jennfier; Dinh, Huyen; Ainscough, Chris; Saur, Genevieve

    2015-05-01

    This publication includes 14 composite data products (CDPs) produced in 2015 for fuel cell technology status, focusing on state-of-the-art fuel cell voltage durability.

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

    DOE Patents [OSTI]

    Murty, Balarama Vempaty (West Bloomfield, MI)

    2000-01-01

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

  1. Sacramento Area Voltage Support Final Environmental Impact Statement

    SciTech Connect (OSTI)

    N /A

    2003-09-19

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

  2. Energy Recovery from High-frequency Clocks using DC-DC Converters M. Alimadadi, S. Sheikhaei, G. Lemieux, S. Mirabbasi, W. Dunford, P. Palmer.

    E-Print Network [OSTI]

    Lemieux, Guy

    . The redeployment reduces the total current draw from the primary supply. We call this concept energy recycling [4 with an increase in operating frequency. As a result, a large fraction of the total energy budget is used is the efficient generation of an on-chip voltage supply which differs from the level offered by the primary supply

  3. Blazar Variability and Evolution in the GeV Regime

    E-Print Network [OSTI]

    Tsujimoto, S; Nishijima, K; Kodani, K

    2015-01-01

    One of the most important problem of the blazar astrophysics is to understand the physical origin of the blazar sequence. In this study, we focus on the GeV gamma-ray variability of blazars and evolution perspective we search the relation between the redshift and the variability amplitude of blazars for each blazar subclass. We analyzed the Fermi-LAT data of the TeV blazars and the bright AGNs (flux $\\geq$ 4$\\times10^{-9}$ cm$^{-2}$s$^{-1}$) selected from the 2LAC (the 2nd LAT AGN catalog) data base. As a result, we found a hint of the correlation between the redshift and the variability amplitude in the FSRQs. Furthermore the BL Lacs which have relatively lower peak frequency of the synchrotron radiation and relatively lower redshift, have a tendency to have a smaller variability amplitude.

  4. AUTO ID FUTURE - FREQUENCY AGNOSTIC

    E-Print Network [OSTI]

    DATTA, SHOUMEN

    Identification of information is one key to the development of intelligent decision systems of the future. Frequency agnostic automatic identification is only one step in the physical world to make physical objects identify ...

  5. Microwave and Radio Frequency Workshop

    Broader source: Energy.gov [DOE]

    At the Microwave and Radio Frequency Workshop (held in Long Beach, CA, on July 25, 2012), academic and industry experts discussed the existing and emerging electrotechnologies – such as microwave ...

  6. Holocene flood frequency across the Central Alps e solar forcing and evidence for variations in North Atlantic atmospheric circulation

    E-Print Network [OSTI]

    Gilli, Adrian

    Holocene flood frequency across the Central Alps e solar forcing and evidence for variations Available online Keywords: Alps Lake sediments Heavy precipitation Flood reconstruction Solar forcing NAO the past natural variability of floods caused by heavy precipitation constitutes important input

  7. Observation of multi-scale oscillation of laminar lifted flames with low-frequency AC electric fields

    SciTech Connect (OSTI)

    Ryu, S.K.; Kim, Y.K.; Kim, M.K.; Won, S.H. [School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 151-742 (Korea); Chung, S.H. [Clean Combustion Research Center, King Abdullah University of Science and Technology, Thuwal (Saudi Arabia)

    2010-01-15

    The oscillation behavior of laminar lifted flames under the influence of low-frequency AC has been investigated experimentally in coflow jets. Various oscillation modes were existed depending on jet velocity and the voltage and frequency of AC, especially when the AC frequency was typically smaller than 30 Hz. Three different oscillation modes were observed: (1) large-scale oscillation with the oscillation frequency of about 0.1 Hz, which was independent of the applied AC frequency, (2) small-scale oscillation synchronized to the applied AC frequency, and (3) doubly-periodic oscillation with small-scale oscillation embedded in large-scale oscillation. As the AC frequency decreased from 30 Hz, the oscillation modes were in the order of the large-scale oscillation, doubly-periodic oscillation, and small-scale oscillation. The onset of the oscillation for the AC frequency smaller than 30 Hz was in close agreement with the delay time scale for the ionic wind effect to occur, that is, the collision response time. Frequency-doubling behavior for the small-scale oscillation has also been observed. Possible mechanisms for the large-scale oscillation and the frequency-doubling behavior have been discussed, although the detailed understanding of the underlying mechanisms will be a future study. (author)

  8. Frequency regulator for synchronous generators

    DOE Patents [OSTI]

    Karlicek, R.F.

    1982-08-10

    The present invention is directed to a novel frequency regulator which controls a generator output frequency for variations in both the input power to the generator and the power supplied to an uncontrolled external load. The present invention further includes over current and current balance protection devices which are relatively inexpensive to manufacture, which may be encapsulated to provide protection from the operating environment and which respond more quickly than previously known electromechanical devices. 11 figs.

  9. Frequency regulator for synchronous generators

    DOE Patents [OSTI]

    Karlicek, Robert F. (1920 Camino Centroloma, Fullerton, CA 92633)

    1982-01-01

    The present invention is directed to a novel frequency regulator which controls a generator output frequency for variations in both the input power to the generator and the power supplied to an uncontrolled external load. The present invention further includes over current and current balance protection devices which are relatively inexpensive to manufacture, which may be encapsulated to provide protection from the operating environment and which respond more quickly than previously known electromechanical devices.

  10. Variable Valve Actuation

    SciTech Connect (OSTI)

    Jeffrey Gutterman; A. J. Lasley

    2008-08-31

    Many approaches exist to enable advanced mode, low temperature combustion systems for diesel engines - such as premixed charge compression ignition (PCCI), Homogeneous Charge Compression Ignition (HCCI) or other HCCI-like combustion modes. The fuel properties and the quantity, distribution and temperature profile of air, fuel and residual fraction in the cylinder can have a marked effect on the heat release rate and combustion phasing. Figure 1 shows that a systems approach is required for HCCI-like combustion. While the exact requirements remain unclear (and will vary depending on fuel, engine size and application), some form of substantially variable valve actuation is a likely element in such a system. Variable valve actuation, for both intake and exhaust valve events, is a potent tool for controlling the parameters that are critical to HCCI-like combustion and expanding its operational range. Additionally, VVA can be used to optimize the combustion process as well as exhaust temperatures and impact the after treatment system requirements and its associated cost. Delphi Corporation has major manufacturing and product development and applied R&D expertise in the valve train area. Historical R&D experience includes the development of fully variable electro-hydraulic valve train on research engines as well as several generations of mechanical VVA for gasoline systems. This experience has enabled us to evaluate various implementations and determine the strengths and weaknesses of each. While a fully variable electro-hydraulic valve train system might be the 'ideal' solution technically for maximum flexibility in the timing and control of the valve events, its complexity, associated costs, and high power consumption make its implementation on low cost high volume applications unlikely. Conversely, a simple mechanical system might be a low cost solution but not deliver the flexibility required for HCCI operation. After modeling more than 200 variations of the mechanism it was determined that the single cam design did not have enough flexibility to satisfy three critical OEM requirements simultaneously, (maximum valve lift variation, intake valve opening timing and valve closing duration), and a new approach would be necessary. After numerous internal design reviews including several with the OEM a dual cam design was developed that had the flexibility to meet all motion requirements. The second cam added complexity to the mechanism however the cost was offset by the deletion of the electric motor required in the previous design. New patent applications including detailed drawings and potential valve motion profiles were generated and alternate two cam designs were proposed and evaluated for function, cost, reliability and durability. Hardware was designed and built and testing of sample hardware was successfully completed on an engine test stand. The mechanism developed during the course of this investigation can be applied by Original Equipment Manufacturers, (OEM), to their advanced diesel engines with the ultimate goal of reducing emissions and improving fuel economy. The objectives are: (1) Develop an optimal, cost effective, variable valve actuation (VVA) system for advanced low temperature diesel combustion processes. (2) Design and model alternative mechanical approaches and down-select for optimum design. (3) Build and demonstrate a mechanism capable of application on running engines.

  11. Stepped frequency ground penetrating radar

    DOE Patents [OSTI]

    Vadnais, Kenneth G. (Ojai, CA); Bashforth, Michael B. (Buellton, CA); Lewallen, Tricia S. (Ventura, CA); Nammath, Sharyn R. (Santa Barbara, CA)

    1994-01-01

    A stepped frequency ground penetrating radar system is described comprising an RF signal generating section capable of producing stepped frequency signals in spaced and equal increments of time and frequency over a preselected bandwidth which serves as a common RF signal source for both a transmit portion and a receive portion of the system. In the transmit portion of the system the signal is processed into in-phase and quadrature signals which are then amplified and then transmitted toward a target. The reflected signals from the target are then received by a receive antenna and mixed with a reference signal from the common RF signal source in a mixer whose output is then fed through a low pass filter. The DC output, after amplification and demodulation, is digitized and converted into a frequency domain signal by a Fast Fourier Transform. A plot of the frequency domain signals from all of the stepped frequencies broadcast toward and received from the target yields information concerning the range (distance) and cross section (size) of the target.

  12. Apparatus and method for detecting and measuring changes in linear relationships between a number of high frequency signals

    DOE Patents [OSTI]

    Bittner, John W. (Shoreham, NY); Biscardi, Richard W. (Ridge, NY)

    1991-01-01

    An electronic measurement circuit for high speed comparison of the relative amplitudes of a predetermined number of electrical input signals independent of variations in the magnitude of the sum of the signals. The circuit includes a high speed electronic switch that is operably connected to receive on its respective input terminals one of said electrical input signals and to have its common terminal serve as an input for a variable-gain amplifier-detector circuit that is operably connected to feed its output to a common terminal of a second high speed electronic switch. The respective terminals of the second high speed electronic switch are operably connected to a plurality of integrating sample and hold circuits, which in turn have their outputs connected to a summing logic circuit that is operable to develop first, second and third output voltages, the first output voltage being proportional to a predetermined ratio of sums and differences between the compared input signals, the second output voltage being proportional to a second summed ratio of predetermined sums and differences between said input signals, and the third output voltage being proportional to the sum of signals to the summing logic circuit. A servo system that is operably connected to receive said third output signal and compare it with a reference voltage to develop a slowly varying feedback voltage to control the variable-gain amplifier in said common amplifier-detector circuit in order to make said first and second output signals independent of variations in the magnitude of the sum of said input signals.

  13. Energy and Transient Power MinimizationEnergy and Transient Power Minimization using Multiple Supply Voltages andusing Multiple Supply Voltages and

    E-Print Network [OSTI]

    Mohanty, Saraju P.

    Activity (N or E(sw)): no switching no power loss !!! Not in fully under designers control. Switching Architecture · Datapath Scheduling Schemes for Power Minimization · Image Watermarking Chip Design different frequencies. #12;Why LowWhy Low--Power Design/Synthesis ?Power Design/Synthesis ? Major Motivation

  14. Aalborg Universitet Review on Multi-Level Voltage Source Converter Based HVDC Technologies for Grid

    E-Print Network [OSTI]

    Bak, Claus Leth

    Connection of Large Offshore Wind Farms Glasdam, Jakob ; Hjerrild, Jesper; Kocewiak, Lukasz Hubert; Bak-Level Voltage Source Converter Based HVDC Technologies for Grid Connection of Large Offshore Wind Farms. I IEEE of large offshore wind farms (OWFs) employing current state-of- the-art voltage source converter based high

  15. A New Thermal-Conscious System-Level Methodology for Energy-Efficient Processor Voltage Selection

    E-Print Network [OSTI]

    Wang, Yu

    A New Thermal-Conscious System-Level Methodology for Energy-Efficient Processor Voltage Selection a thermal-conscious system-level methodology to make energy-efficient voltage selection (VS) for nanometer), thermal resistance, are integrated and considered in our system models, and their impacts on energy

  16. Low-voltage, low-power, low switching error, class-AB switched current

    E-Print Network [OSTI]

    Serdijn, Wouter A.

    Low-voltage, low-power, low switching error, class-AB switched current memory cell C. Sawigun and W into two components by a low-voltage class-AB current splitter and subsequently processes the individual signals by two low switching error class-A memory cells. As a conse- quence, the output current obtained

  17. Public Opinions of Building Additional High-Voltage Electric Power Lines

    E-Print Network [OSTI]

    Tesfatsion, Leigh

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

  18. Senderovich 1 Electrode Design Adjustments to a High Voltage Electron Gun

    E-Print Network [OSTI]

    Hoffstaetter, Georg

    Senderovich 1 Electrode Design Adjustments to a High Voltage Electron Gun Igor Senderovich Abstract, a very high voltage electron gun needs to be designed.1 To these ends, several geometric parameters were were performed on off-axis electron acceleration. Introduction The design of the electrode gun has

  19. Voltage-dependent behavior of a "ball-and-chain" gramicidin channel

    E-Print Network [OSTI]

    Woolley, G. Andrew; Zunic, Valentin; Karanicolas, John; Jaikaran, Anna S. I.; Starostin, Andrei V.

    1997-11-01

    -trans isomerization on the 10–100-ms time scale. The conductance behavior of gram-EDA is found to be markedly voltage dependent, whereas the behavior of gram-DMEDA is not. In addition, voltage affects the cis-trans ratios of the carbamate groups of gram...

  20. An ultra-low voltage high gain operational transconductance amplifier for biomedical

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    An ultra-low voltage high gain operational transconductance amplifier for biomedical applications that work at ultra low voltage power supply. Moreover, low power dissipation is essential in these systems dissipation is also proposed in [5]. Differential pairs are commonly used as input stages, in an ultra-low

  1. Variation-aware Clock Network Design Methodology for Ultra-Low Voltage (ULV) Circuits

    E-Print Network [OSTI]

    Lim, Sung Kyu

    Variation-aware Clock Network Design Methodology for Ultra-Low Voltage (ULV) Circuits Xin Zhao networks for ultra-low voltage (ULV) circuits. We show that both clock slew and skew play important roles) at comparable or even higher Fmax compared with the existing methods. Keywords--clock network design, ultra-low

  2. PHYSICS 327 Spring 2015 1/13/2015 LAB 1 -DC VOLTAGE DIVIDER

    E-Print Network [OSTI]

    Gustafsson, Torgny

    produces output voltage which is independent of the load resistance (RL, in this case). Remember a provided "power supply" for the source of the input voltage Vin. The circuit is described by the equation 2 (breadboard), and use the power supply to provide Vin = 12 V. For each value of R2, measure Vin and Vout

  3. Aalborg Universitet SiC heat pump converters with support for voltage unbalance in distribution grids

    E-Print Network [OSTI]

    Munk-Nielsen, Stig

    Aalborg Universitet SiC heat pump converters with support for voltage unbalance in distribution (APA): Trintis, I., Douglass, P., Maheshwari, R., & Munk-Nielsen, S. (2015). SiC heat pump converters.aau.dk on: november 29, 2015 #12;SiC heat pump converters with support for voltage unbalance in distribution

  4. HF Multiresonant Electronic Ballast for Fluorescent Lamps with Constant Filament Preheat Voltage

    E-Print Network [OSTI]

    HF Multiresonant Electronic Ballast for Fluorescent Lamps with Constant Filament Preheat Voltage resonance arrangement that acts as a current source. During warm up the filaments are driven by a secondary the filament and shorts out the voltage across the lamp. Simulation and experimental results suggest

  5. A Static PatternIndependent Technique for Power Grid Voltage Integrity Verification #

    E-Print Network [OSTI]

    Najm, Farid N.

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

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

    E-Print Network [OSTI]

    Najm, Farid N.

    by the circuit off the grid. The current waveforms of these current sources may be determined by a priorA Static Pattern-Independent Technique for Power Grid Voltage Integrity Verification Dionysios Design verification must include the power grid. Checking that the voltage on the power grid does

  7. Effect of Flow Field Design and Voltage Change Range on the Dynamic Behavior of PEMFCs

    E-Print Network [OSTI]

    Van Zee, John W.

    Effect of Flow Field Design and Voltage Change Range on the Dynamic Behavior of PEMFCs Sunhoe Kim exchange membrane fuel cell PEMFC subjected to rapid changes in the voltage depends on the type of flow that these peak heights are limited primarily by oxygen mass transfer, even though the PEMFC is operating at close

  8. Aalborg Universitet Voltage Scheduling Droop Control for State-of-Charge Balance of Distributed Energy

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    ., & Guerrero, J. M. (2014). Voltage Scheduling Droop Control for State-of-Charge Balance of Distributed Energy-of-Charge Balance of Distributed Energy Storage in DC Microgrids," in Proc. IEEE International Energy Conference (EnergyCon'14), 2014. Voltage Scheduling Droop Control for State-of- Charge Balance of Distributed Energy

  9. Ca2 -dependent activation of Cl currents in Xenopus oocytes is modulated by voltage

    E-Print Network [OSTI]

    Parker, Ian

    a fast electrical block to polyspermy in the egg (7). Voltage-clamp recordings of Cl current provide- acteristics that complicate interpretation of the under- lying Ca2 signals (11, 21). In particular, it remains sources of Ca2 can be discriminated by recording ICl,Ca evoked by hyperpolarizing voltage steps because

  10. Accumulation capacitance frequency dispersion of III-V metal-insulator-semiconductor devices due to disorder induced gap states

    SciTech Connect (OSTI)

    Galatage, R. V. [Department of Electrical Engineering, The University of Texas at Dallas, Richardson, Texas 75080 (United States); Zhernokletov, D. M. [Department of Materials Science and Engineering, The University of Texas at Dallas, Richardson, Texas 75080 (United States); Dong, H.; Brennan, B.; Hinkle, C. L. [Department of Physics, The University of Texas at Dallas, Richardson, Texas 75080 (United States); Wallace, R. M. [Department of Materials Science and Engineering, The University of Texas at Dallas, Richardson, Texas 75080 (United States); Department of Physics, The University of Texas at Dallas, Richardson, Texas 75080 (United States); Vogel, E. M. [School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)

    2014-07-07

    The origin of the anomalous frequency dispersion in accumulation capacitance of metal-insulator-semiconductor devices on InGaAs and InP substrates is investigated using modeling, electrical characterization, and chemical characterization. A comparison of the border trap model and the disorder induced gap state model for frequency dispersion is performed. The fitting of both models to experimental data indicate that the defects responsible for the measured dispersion are within approximately 0.8 nm of the surface of the crystalline semiconductor. The correlation between the spectroscopically detected bonding states at the dielectric/III-V interface, the interfacial defect density determined using capacitance-voltage, and modeled capacitance-voltage response strongly suggests that these defects are associated with the disruption of the III-V atomic bonding and not border traps associated with bonding defects within the high-k dielectric.

  11. Frequency Stability of Atomic Frequency Standards beyond Quantum Projection Noise

    E-Print Network [OSTI]

    G. M. Saxena

    2011-04-07

    In this paper we describe that the optically pumped frequency standards can have frequency stability beyond the quantum noise limit by detecting the Ramsey resonance through the squeezed light. In this paper we report that instead of considering the interaction of entangled atoms in the microwave region, it will be more practical to create the entanglement of the atoms in the detection region using the squeezed light, which is also used for the detection of the Ramsey resonance. The advantage of squeezing can be derived when the technical noises have been removed.

  12. Josephson oscillations in a series array Josephson voltage standard

    SciTech Connect (OSTI)

    Meyer, H.G.; Krech, W.; Mikolajczak, B.

    1989-06-01

    Josephson oscillations in a large series array of Josephson junctions designed as a superconducting microwave transmission line are studied. For descriptions of the Josephson junctions both the Stewart--McCumber model and the Werthamer model are used. The attenuation of the Josephson oscillations in the considered array is composed of two terms rising from the stripline and from the Josephson junctions. The latter one is of increasing significance for lower than usually applied drive frequencies.

  13. Time-frequency analysis and Harmonic Gaussian Functions

    E-Print Network [OSTI]

    Tokiniaina Ranaivoson; Raoelina Andriambololona; Rakotoson Hanitriarivo

    2013-08-08

    A method for time-frequency analysis is given. The approach utilizes properties of Gaussian distribution, properties of Hermite polynomials and Fourier analysis. We begin by the definitions of a set of functions called harmonic Gaussian functions. Then these functions are used to define a set of transformations,noted T_n, which associate to a function {\\psi},of the time variable t, a set of functions {\\Psi}_n which depend on time, frequency and frequency (or time) standard deviation. Some properties of the transformations T_n and the functions {\\Psi}_n are given. It is proved in particular that the square of the modulus of each function {\\Psi}_n can be interpreted as a representation of the energy distribution of the signal, represented by the function {\\psi}, in the time-frequency plane for a given value of the frequency (or time) standard deviation. It is also shown that the function {\\psi}, can be recovered from the functions{\\Psi}_n.

  14. High voltage power supply with modular series resonant inverters

    DOE Patents [OSTI]

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

    1995-07-18

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

  15. High voltage power supply with modular series resonant inverters

    DOE Patents [OSTI]

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

    1995-01-01

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

  16. Low Voltage High Precision Spatial Light ModulatorsFinal Report

    SciTech Connect (OSTI)

    Papavasiliou, A P

    2005-02-09

    The goal of this project was to make LLNL a leader in Spatial Light Modulators (SLMs) by developing the technology that will be needed by the next generation of SLMs. We would use new lower voltage actuators and bond those actuators directly to controlling circuitry to break the fundamental limitations that constrain current SLM technology. This three-year project was underfunded in the first year and not funded in the second year. With the funding that was available, we produced actuators and designs for the controlling circuitry that would have been integrated in the second year. Spatial light modulators (SLMs) are arrays of tiny movable mirrors that modulate the wave-fronts of light. SLMs can correct aberrations in incoming light for adaptive optics or modulate light for beam control, optical communication and particle manipulation. MicroElectroMechanical Systems (MEMS) is a technology that utilizes the microfabrication tools developed by the semiconductor industry to fabricate a wide variety of tiny machines. The first generation of MEMS SLMs have improved the functionality of SLMs while drastically reducing per pixel cost making arrays on the order of 1000 pixels readily available. These MEMS SLMs however are limited by the nature of their designs to be very difficult to scale above 1000 pixels and have very limited positioning accuracy. By co-locating the MEMS mirrors with CMOS electronics, we will increase the scalability and positioning accuracy. To do this we will have to make substantial advances in SLM actuator design, and fabrication.

  17. Low-Frequency Weather and the Emergence of the Climate Department of Physics, McGill University, Montreal, Quebec, Canada

    E-Print Network [OSTI]

    Lovejoy, Shaun

    Low-Frequency Weather and the Emergence of the Climate S. Lovejoy Department of Physics, Mc, Paris, France Météo France, Paris, France We survey atmospheric variability from weather scales up quenched, leading to a scaling "low-frequency weather" regime extending out to c 10­100 years

  18. Decentralized customerlevel under frequency load shedding in...

    Open Energy Info (EERE)

    Decentralized customerlevel under frequency load shedding in Switzerland (Smart Grid Project) Jump to: navigation, search Project Name Decentralized customerlevel under frequency...

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

    SciTech Connect (OSTI)

    Suzer, Sefik; Baer, Donald R.; Engelhard, Mark H.

    2010-06-16

    The impact of solution exposure on the charging properties of oxide coatings on Fe metal-core oxide-shells has been examined by sample biasing during XPS measurements. The Fe nanoparticles were suspended in relatively unreactive acetone and were analyzed after particle containing solutions were deposited on SiO2/Si substrates, and/or Au substrates. The particle and substrate combinations were subjected to ± 10V d.c. biasing in the form of square waves (SQW) pulses with 5V amplitude. The samples experienced variable degrees of charging for which low energy electrons at ~1 eV, 20?A and low energy Ar+ ions were used to minimize. Application of d.c. bias and/or square wave pulses drastically influences the extent of charging, which is utilized to gather additional analytical information about the sample under investigation. This approach allows separation of otherwise overlapping peaks. Accordingly, the O1s peaks of the silicon oxide substrate, the iron oxide nanoparticles, and that of the casting solvent can be separated from each other. Similarly the C1s peak belonging to the solvent can be separated from that of the adventitious carbon. The charging shifts of the iron nanoparticles are strongly influenced by the surrounding solvent. Hence, acetone exhibits the largest shift, water the smallest, and methanol in between. Dynamical measurements performed by application of the voltage stress in the form of SQW pulses gives information about the time constants of the processes involved, which led us postulate that these charging properties we probe in these systems, stem mainly from ionic movement(s).

  20. Two-frequency Ramsey interferometry

    SciTech Connect (OSTI)

    Seidel, D.; Muga, J. G. [Departmento de Quimica-Fisica, Universidad del Pais Vasco, Apartado Postal 644, 48080 Bilbao (Spain)

    2007-02-15

    We investigate Ramsey interferometry for two separated fields oscillating with different frequencies. It is shown that the interplay between average and relative detuning leads to interference effects not present in the standard, single-frequency setup. For a large free-flight time of ground-state atoms before entering the first field region, the Ramsey fringes with respect to the relative detuning become much narrower than the usual ones. The stability of these effects with respect to phase or velocity fluctuations is discussed.