Sample records for ac-dc converters halt

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

    E-Print Network [OSTI]

    Zhang, Yuemin

    1993-01-01T23:59:59.000Z

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

  2. Control of Parallel-Connected Bidirectional AC-DC Converters in Stationary Frame for Microgrid

    E-Print Network [OSTI]

    Teodorescu, Remus

    Control of Parallel-Connected Bidirectional AC-DC Converters in Stationary Frame for Microgrid-- With the penetration of renewable energy in modern power system, microgrid has become a popular application worldwide. In this paper, parallel-connected bidirectional converters for AC and DC hybrid microgrid application

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

    E-Print Network [OSTI]

    Hwang, J. George

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

  4. Development of a 10 kW High Temperature High Power Density Three-Phase AC-DC-AC SiC Converter

    SciTech Connect (OSTI)

    Ning, Puqi [ORNL

    2012-01-01T23:59:59.000Z

    This paper presents the development and experimental performance of a 10 kW, all SiC, 250 C junction temperature high-power-density three-phase ac-dc-ac converter. The electromagnetic interference filter, thermal system, high temperature package, and gate drive design are discussed in detail. Finally, tests confirming the feasibility and validating the theoretical basis of the prototype converter system are described.

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

    E-Print Network [OSTI]

    Essakiappan, Somasundaram

    2011-08-08T23:59:59.000Z

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

  6. E-Print Network 3.0 - ac-dc-ac z-source converter Sample Search...

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

    table... Matrix Converter va vb vc vu vv vw Eq. (5) Virtual Rectifier Control Virtual Inverter Control 9 6 6 3 ACDCAC... Fig. 3. Block diagram of matrix converter controller...

  7. E-Print Network 3.0 - ac-dc back-to-back converter Sample Search...

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

    Collection: Engineering 9 Abstract--In this paper a modular power electronic transformer (PET) for feeding sensitive loads is presented. Summary: is an ACDC converter...

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

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

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

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

    SciTech Connect (OSTI)

    Onar, Omer C [ORNL] [ORNL

    2011-01-01T23:59:59.000Z

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

  10. E-Print Network 3.0 - ac-dc power transmission Sample Search...

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

    Ris Summary: (AEDVESESY) DFIG control Power control loop Speed control loop Wind turbine control Measurement grid point AC DC... reference DFIG control Power control...

  11. Improving the dynamic performance of a complex AC/DC system by HVDC control modifications

    SciTech Connect (OSTI)

    Hammad, A.E. (ABB Power Systems, Baden (CH)); Gagnon, J. (Hydro Quebec, Montreal (CA)); McCallum, D. (IREQ, Montreal (CA))

    1990-10-01T23:59:59.000Z

    The power system of Hydro-Quebec has a peak load of approximately 27 GW. The great distance between the production sites and the load centers introduces stability limitations, which is the reason why the Quebec grid cannot be economically synchronized (through ac transmission with limited capacity) with the U.S. northeastern network. Power exports are therefore dependent on the use of HVDC links of which Hydro-Quebec now possesses five, for a capacity of over 2600 MW. Such a capacity will again soon increase. At the moment, the Chateauguay scheme has the largest HVDC capacity. It transfers 1000 MW by means of two Back-to-Back converter blocks. Various automatic control systems are installed on the Chateauguay scheme owing to the fact that a single circuit of a 765 kV ac line transmits the output of both the HVDC converter stations as well as the output from Beauharnois hydro generating station. Such controls have performed satisfactorily since 1984. However, a remarkable improvement of the overall ac/dc system dynamic performance can be gained by making certain modifications in some of these HVDC system controls. This paper presents the salient features of such control modifications, currently under consideration, using the results of an investigation by digital and analogue simulations that demonstrate the achieved improvements.

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

    E-Print Network [OSTI]

    Qu, Zhihua

    A nonlinear robust HVDC control for a parallel AC/DC power system Hongzhi Cai a , Zhihua Qu b. Keywords: Robust control; HVDC; Power system; Stability; Lyapunov method 1. Introduction It has been recognized that, through an HVDC transmission line, fast electronic control can be applied on the DC power

  13. Comparison of Two Autonomous AC-DC Converters for Piezoelectric Energy Scavenging Systems

    E-Print Network [OSTI]

    Boyer, Edmond

    be very low, the conversion should be as efficient as possible. The paper describes an active AC that they harvest. To reduce and to optimize their power consumption a bias circuit has been designed to make technology. The performances of the two solutions were compared with the ones of a passive Schottky based

  14. Halting in quantum Turing computation

    E-Print Network [OSTI]

    W. L. Fouché; J. Heidema; G. Jones; P. H. Potgieter

    2007-05-22T23:59:59.000Z

    The paper considers the halting scheme for quantum Turing machines. The scheme originally proposed by Deutsch appears to be correct, but not exactly as originally intended. We discuss the result of Ozawa as well as the objections raised by Myers, Kieu and Danos and others. Finally, the relationship of the halting scheme to the quest for a universal quantum Turing machine is considered.

  15. On Halting Process of Quantum Turing Machine

    E-Print Network [OSTI]

    Takayuki Miyadera; Masanori Ohya

    2003-02-07T23:59:59.000Z

    We prove that there is no algorithm to tell whether an arbitrarily constructed Quantum Turing Machine has same time steps for different branches of computation. We, hence, can not avoid the notion of halting to be probabilistic in Quantum Turing Machine. Our result suggests that halting scheme of Quantum Turing Machine and quantum complexity theory based upon the existing halting scheme sholud be reexamined.

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

    SciTech Connect (OSTI)

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

    1988-09-01T23:59:59.000Z

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

  17. On Quantum Turing Machine Halting Deterministically

    E-Print Network [OSTI]

    Min Liang; Li Yang

    2012-02-29T23:59:59.000Z

    We define a subclass of quantum Turing machine (QTM) named SR-QTM, which halts deterministically and has deterministic tape head position. A quantum state transition diagram (QSTD) is proposed to describe SR-QTM. With the help of QSTD, we construct a SR-QTM which is universal for all near-trivial transformations. This means there exists a QTM which is universal for the above subclass. Finally we prove that SR-QTM is computational equivalent with ordinary QTM in the bounded error setting. It can be seen that, because SR-QTM has the same time steps for different branches of computation, the halting scheme problem will not exist when considering SR-QTM as a model of quantum computing.

  18. On Quantum Turing Machine Halting Deterministically

    E-Print Network [OSTI]

    Liang, Min

    2012-01-01T23:59:59.000Z

    We define a subclass of quantum Turing machine (QTM) named SR-QTM, which halts deterministically and has deterministic tape head position. A quantum state transition diagram (QSTD) is proposed to describe SR-QTM. With the help of QSTD, we construct a SR-QTM which is universal for all near-trivial transformations. This means there exists a QTM which is universal for the above subclass. Finally we prove that SR-QTM is computational equivalent with ordinary QTM in the bounded error setting. It can be seen that, because SR-QTM has the same time steps for different branches of computation, the halting scheme problem will not exist when considering SR-QTM as a model of quantum computing.

  19. Quantum Turing Machines: Local Transition, Preparation, Measurement, and Halting

    E-Print Network [OSTI]

    Masanao Ozawa

    1998-09-14T23:59:59.000Z

    Foundations of the theory of quantum Turing machines are investigated. The protocol for the preparation and the measurement of quantum Turing machines is discussed. The local transition functions are characterized for fully general quantum Turing machines. A new halting protocol is proposed without augmenting the halting qubit and is shown to work without spoiling the computation.

  20. Fetch Halting on Critical Load Misses Nikil Mehta,

    E-Print Network [OSTI]

    DeHon, André

    Fetch Halting on Critical Load Misses Nikil Mehta, Brian Singer, R. Iris Bahar Division, such as loads that miss to main memory and floating point arithmetic operations, are primarily responsible to characterize critical instructions, our approach com- bines software profiling and hardware monitoring

  1. DOE Orders AeroSys to Halt Distribution of Inefficient Air Conditioner...

    Energy Savers [EERE]

    Orders AeroSys to Halt Distribution of Inefficient Air Conditioner and Heat Pump Models DOE Orders AeroSys to Halt Distribution of Inefficient Air Conditioner and Heat Pump Models...

  2. DOE Orders AeroSys to Halt Distribution of Inefficient Air Conditioner...

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

    Orders AeroSys to Halt Distribution of Inefficient Air Conditioner and Heat Pump Models Shown to Violate Minimum Efficiency Standards DOE Orders AeroSys to Halt Distribution of...

  3. DOE Requires Manufacturers to Halt Sales of Heat Pumps and Air...

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

    Minimum Appliance Standards DOE Requires Manufacturers to Halt Sales of Heat Pumps and Air Conditioners Violating Minimum Appliance Standards June 3, 2010 - 2:17pm Addthis...

  4. Thermionic converter

    DOE Patents [OSTI]

    Fitzpatrick, G.O.

    1987-05-19T23:59:59.000Z

    A thermionic converter is set forth which includes an envelope having an electron collector structure attached adjacent to a wall. An electron emitter structure is positioned adjacent the collector structure and spaced apart from opposite wall. The emitter and collector structures are in a common chamber. The emitter structure is heated substantially only by thermal radiation. Very small interelectrode gaps can be maintained utilizing the thermionic converter whereby increased efficiency results. 10 figs.

  5. Thermionic converter

    DOE Patents [OSTI]

    Fitzpatrick, Gary O. (Livermore, CA)

    1987-05-19T23:59:59.000Z

    A thermionic converter (10) is set forth which includes an envelope (12) having an electron collector structure (22) attached adjacent to a wall (16). An electron emitter structure (24) is positioned adjacent the collector structure (22) and spaced apart from opposite wall (14). The emitter (24) and collector (22) structures are in a common chamber (20). The emitter structure (24) is heated substantially only by thermal radiation. Very small interelectrode gaps (28) can be maintained utilizing the thermionic converter (10) whereby increased efficiency results.

  6. High frequency AC power converter for low voltage circuits

    E-Print Network [OSTI]

    Salazar, Nathaniel Jay Tobias

    2012-01-01T23:59:59.000Z

    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 ...

  7. Thermionic converter

    SciTech Connect (OSTI)

    Fitzpatrick, G.O.

    1987-05-19T23:59:59.000Z

    A thermionic converter is described comprising: an envelope having first and second walls spaced apart from one another. The envelope defines an enclosed chamber; an electron collector structure attached adjacent to the second wall; an electron emitter structure, located adjacent the collector structure and between the collector structure and the first wall. At least a respective one of the collector structure and the emitter structure comprise elements, each of the elements along with a respective other of the collector structure and the emitter structure defining interelectrode gaps at least when the emitter structure is above a selected temperature. The emitter structure is spaced a distance away from the first wall and is positioned to receive substantially only thermal radiation.

  8. A Bidirectional High-Power-Quality Grid Interface With a Novel Bidirectional Noninverted Buck Boost Converter for PHEVs

    SciTech Connect (OSTI)

    Onar, Omer C [ORNL

    2012-01-01T23:59:59.000Z

    Plug-in hybrid electric vehicles (PHEVs) will play a vital role in future sustainable transportation systems due to their potential in terms of energy security, decreased environmental impact, improved fuel economy, and better performance. Moreover, new regulations have been established to improve the collective gas mileage, cut greenhouse gas emissions, and reduce dependence on foreign oil. This paper primarily focuses on two major thrust areas of PHEVs. First, it introduces a grid-friendly bidirectional alternating current/direct current ac/dc dc/ac rectifier/inverter for facilitating vehicle-to-grid (V2G) integration of PHEVs. Second, it presents an integrated bidirectional noninverted buck boost converter that interfaces the energy storage device of the PHEV to the dc link in both grid-connected and driving modes. The proposed bidirectional converter has minimal grid-level disruptions in terms of power factor and total harmonic distortion, with less switching noise. The integrated bidirectional dc/dc converter assists the grid interface converter to track the charge/discharge power of the PHEV battery. In addition, while driving, the dc/dc converter provides a regulated dc link voltage to the motor drive and captures the braking energy during regenerative braking.

  9. AC/DC Conversion - October 2005

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLasDelivered‰PNGExperience4AJ01) (See95TI07) (See4AJ01)59AJ76)74AJ01)BROWNE,8 - March 31,

  10. Combustion converter design evolution

    SciTech Connect (OSTI)

    Goodale, D.B.; Miskolczy, G.

    1984-08-01T23:59:59.000Z

    The early thermionic converters used hemispherical one-inch-diameter hot shells. They were extensively tested in a natural gas, high-temperature furnace. A converter was life tested for 12,500 hours at emitter temperatures above 1700 K. Two-inch diameter converters with both hemispherical and torispherical shapes were developed next. These converters have been tested in both natural gas-, oil-, and coal-oil slurry-fired environments. A prototype converter for cogeneration applications was also developed using this emitter configuration. A six converter module of cogeneration converters has been constructed.

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

    SciTech Connect (OSTI)

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

    1994-09-01T23:59:59.000Z

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

  12. ITER convertible blanket evaluation

    SciTech Connect (OSTI)

    Wong, C.P.C.; Cheng, E.

    1995-09-01T23:59:59.000Z

    Proposed International Thermonuclear Experimental Reactor (ITER) convertible blankets were reviewed. Key design difficulties were identified. A new particle filter concept is introduced and key performance parameters estimated. Results show that this particle filter concept can satisfy all of the convertible blanket design requirements except the generic issue of Be blanket lifetime. If the convertible blanket is an acceptable approach for ITER operation, this particle filter option should be a strong candidate.

  13. Interleaved power converter

    DOE Patents [OSTI]

    Zhu, Lizhi (Canton, MI)

    2007-11-13T23:59:59.000Z

    A power converter architecture interleaves full bridge converters to alleviate thermal management problems in high current applications, and may, for example, double the output power capability while reducing parts count and costs. For example, one phase of a three phase inverter is shared between two transformers, which provide power to a rectifier such as a current doubler rectifier to provide two full bridge DC/DC converters with three rather than four high voltage inverter legs.

  14. Universal thermochemical energy converter

    DOE Patents [OSTI]

    Labinov, Solomon Davidovich (Oak Ridge, TN); Sand, James R. (Oak Ridge, TN); Conklin, James C. (Knoxville, TN); VanCoevering, James (Oak Ridge, TN); Courville, George E. (Oak Ridge, TN)

    2001-01-01T23:59:59.000Z

    Disclosed are methods and apparatus for a thermochemical closed cycle employing a polyatomic, chemically active working fluid for converting heat energy into useful work.

  15. WBG Converters and Chargers

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

    * Finish - FY16 * 38 % complete * Reducing onboard battery charger and dc-dc converter cost, weight, and volume * Achieving high efficiency * Overcoming limitations of present...

  16. Microminiature thermionic converters

    DOE Patents [OSTI]

    King, Donald B. (Albuquerque, NM); Sadwick, Laurence P. (Salt Lake City, UT); Wernsman, Bernard R. (Clairton, PA)

    2001-09-25T23:59:59.000Z

    Microminiature thermionic converts (MTCs) having high energy-conversion efficiencies and variable operating temperatures. Methods of manufacturing those converters using semiconductor integrated circuit fabrication and micromachine manufacturing techniques are also disclosed. The MTCs of the invention incorporate cathode to anode spacing of about 1 micron or less and use cathode and anode materials having work functions ranging from about 1 eV to about 3 eV. Existing prior art thermionic converter technology has energy conversion efficiencies ranging from 5-15%. The MTCs of the present invention have maximum efficiencies of just under 30%, and thousands of the devices can be fabricated at modest costs.

  17. Vector generator scan converter

    DOE Patents [OSTI]

    Moore, J.M.; Leighton, J.F.

    1988-02-05T23:59:59.000Z

    High printing speeds for graphics data are achieved with a laser printer by transmitting compressed graphics data from a main processor over an I/O channel to a vector generator scan converter which reconstructs a full graphics image for input to the laser printer through a raster data input port. The vector generator scan converter includes a microprocessor with associated microcode memory containing a microcode instruction set, a working memory for storing compressed data, vector generator hardware for drawing a full graphic image from vector parameters calculated by the microprocessor, image buffer memory for storing the reconstructed graphics image and an output scanner for reading the graphics image data and inputting the data to the printer. The vector generator scan converter eliminates the bottleneck created by the I/O channel for transmitting graphics data from the main processor to the laser printer, and increases printer speed up to thirty fold. 7 figs.

  18. Vector generator scan converter

    DOE Patents [OSTI]

    Moore, James M. (Livermore, CA); Leighton, James F. (Livermore, CA)

    1990-01-01T23:59:59.000Z

    High printing speeds for graphics data are achieved with a laser printer by transmitting compressed graphics data from a main processor over an I/O (input/output) channel to a vector generator scan converter which reconstructs a full graphics image for input to the laser printer through a raster data input port. The vector generator scan converter includes a microprocessor with associated microcode memory containing a microcode instruction set, a working memory for storing compressed data, vector generator hardward for drawing a full graphic image from vector parameters calculated by the microprocessor, image buffer memory for storing the reconstructed graphics image and an output scanner for reading the graphics image data and inputting the data to the printer. The vector generator scan converter eliminates the bottleneck created by the I/O channel for transmitting graphics data from the main processor to the laser printer, and increases printer speed up to thirty fold.

  19. Liquid metal thermal electric converter

    DOE Patents [OSTI]

    Abbin, Joseph P. (Albuquerque, NM); Andraka, Charles E. (Albuquerque, NM); Lukens, Laurance L. (Albuquerque, NM); Moreno, James B. (Albuquerque, NM)

    1989-01-01T23:59:59.000Z

    A liquid metal thermal electric converter which converts heat energy to electrical energy. The design of the liquid metal thermal electric converter incorporates a unique configuration which directs the metal fluid pressure to the outside of the tube which results in the structural loads in the tube to be compressive. A liquid metal thermal electric converter refluxing boiler with series connection of tubes and a multiple cell liquid metal thermal electric converter are also provided.

  20. DC systems with transformerless converters

    SciTech Connect (OSTI)

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

    1995-07-01T23:59:59.000Z

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

  1. Cycloidal Wave Energy Converter

    SciTech Connect (OSTI)

    Stefan G. Siegel, Ph.D.

    2012-11-30T23:59:59.000Z

    This program allowed further advancing the development of a novel type of wave energy converter, a Cycloidal Wave Energy Converter or CycWEC. A CycWEC consists of one or more hydrofoils rotating around a central shaft, and operates fully submerged beneath the water surface. It operates under feedback control sensing the incoming waves, and converts wave power to shaft power directly without any intermediate power take off system. Previous research consisting of numerical simulations and two dimensional small 1:300 scale wave flume experiments had indicated wave cancellation efficiencies beyond 95%. The present work was centered on construction and testing of a 1:10 scale model and conducting two testing campaigns in a three dimensional wave basin. These experiments allowed for the first time for direct measurement of electrical power generated as well as the interaction of the CycWEC in a three dimensional environment. The Atargis team successfully conducted two testing campaigns at the Texas A&M Offshore Technology Research Center and was able to demonstrate electricity generation. In addition, three dimensional wave diffraction results show the ability to achieve wave focusing, thus increasing the amount of wave power that can be extracted beyond what was expected from earlier two dimensional investigations. Numerical results showed wave cancellation efficiencies for irregular waves to be on par with results for regular waves over a wide range of wave lengths. Using the results from previous simulations and experiments a full scale prototype was designed and its performance in a North Atlantic wave climate of average 30kW/m of wave crest was estimated. A full scale WEC with a blade span of 150m will deliver a design power of 5MW at an estimated levelized cost of energy (LCOE) in the range of 10-17 US cents per kWh. Based on the new results achieved in the 1:10 scale experiments these estimates appear conservative and the likely performance at full scale will exceed this initial performance estimates. In advancing the Technology Readiness Level (TRL) of this type of wave energy converter from 3 to 4, we find the CycWEC to exceed our initial estimates in terms of hydrodynamic performance. Once fully developed and optimized, it has the potential to not just outperform all other WEC technologies, but to also deliver power at a lower LCOE than competing conventional renewables like wind and solar. Given the large wave power resource both domestically and internationally, this technology has the potential to lead to a large improvement in our ability to produce clean electricity at affordable cost.

  2. Thermionic electric converter

    SciTech Connect (OSTI)

    Davis, E.D.

    1981-12-01T23:59:59.000Z

    A thermionic electric converter is disclosed wherein an externally located heat source causes electrons to be boiled off an electron emissive surface interiorly positioned on one end wall of an evacuated cylindrical chamber. The electrons are electrically focused and accelerated through the interior of an air core induction coil located within a transverse magnetic field, and subsequently are collected on the other end wall of the chamber functioning as a collecting plate. The emf generated in the induction coil by action of the transiting electron stream interacting with the transverse magnetic field is applied to an external circuit to perform work, thereby implementing a direct heat energy to electrical energy conversion.

  3. Solar thermionic energy converter experiment

    SciTech Connect (OSTI)

    Goodale, D.; Lieb, D.; Neale, D.

    1982-08-01T23:59:59.000Z

    A one-inch CVD converter was solar tested in a central receiver heliostat array at the Advanced Components Test Facility at the Georgia Institute of Technology. The test examined heat flux cycling control of the operating point and mounting arrangements. The converter was mounted directly in the solar image with no cavity. The input heat flux was 40-60 W/cm/sup 2/. The converter performance was comparable to combustion measurements made on the same diode. Thermal cycling caused no problems with converter operation. The converter showed no degradation after the test.

  4. Bidirectional buck boost converter

    DOE Patents [OSTI]

    Esser, A.A.M.

    1998-03-31T23:59:59.000Z

    A bidirectional buck boost converter and method of operating the same allows regulation of power flow between first and second voltage sources in which the voltage level at each source is subject to change and power flow is independent of relative voltage levels. In one embodiment, the converter is designed for hard switching while another embodiment implements soft switching of the switching devices. In both embodiments, first and second switching devices are serially coupled between a relatively positive terminal and a relatively negative terminal of a first voltage source with third and fourth switching devices serially coupled between a relatively positive terminal and a relatively negative terminal of a second voltage source. A free-wheeling diode is coupled, respectively, in parallel opposition with respective ones of the switching devices. An inductor is coupled between a junction of the first and second switching devices and a junction of the third and fourth switching devices. Gating pulses supplied by a gating circuit selectively enable operation of the switching devices for transferring power between the voltage sources. In the second embodiment, each switching device is shunted by a capacitor and the switching devices are operated when voltage across the device is substantially zero. 20 figs.

  5. Self-powered microthermionic converter

    DOE Patents [OSTI]

    Marshall, Albert C.; King, Donald B.; Zavadil, Kevin R.; Kravitz, Stanley H.; Tigges, Chris P.; Vawter, Gregory A.

    2004-08-10T23:59:59.000Z

    A self-powered microthermionic converter having an internal thermal power source integrated into the microthermionic converter. These converters can have high energy-conversion efficiencies over a range of operating temperatures. Microengineering techniques are used to manufacture the converter. The utilization of an internal thermal power source increases potential for mobility and incorporation into small devices. High energy efficiency is obtained by utilization of micron-scale interelectrode gap spacing. Alpha-particle emitting radioisotopes can be used for the internal thermal power source, such as curium and polonium isotopes.

  6. FLUXCAP: A flux-coupled ac/dc magnetizing device

    E-Print Network [OSTI]

    Gopman, Daniel B; Kent, Andrew D

    2012-01-01T23:59:59.000Z

    We report on an instrument for applying ac and dc magnetic fields by capturing the flux from a rotating permanent magnet and projecting it between two adjustable pole pieces. This can be an alternative to standard electromagnets for experiments with small samples or in probe stations in which an applied magnetic field is needed locally, with advantages that include a compact form-factor, very low power requirements and dissipation as well as fast field sweep rates. This flux capture instrument (FLUXCAP) can produce fields from -400 to +400 mT, with field resolution less than 1 mT. It generates static magnetic fields as well as ramped fields, with ramping rates as high as 10 T/s. We demonstrate the use of this apparatus for studying the magnetotransport properties of spin-valve nanopillars, a nanoscale device that exhibits giant magnetoresistance.

  7. On the Road to Climate Stability: The Parable of the Secretary A-Team Report on Prospects for Halting the Growth of CO2 Emissions

    E-Print Network [OSTI]

    Hansen, James E.

    for Halting the Growth of CO2 Emissions James Hansen1,2, Darnell Cain3, Robert Schmunk3 After President Bush) reducing non-CO2 climate forcings, and (2) getting CO2 emissions to level out in the near-term and decline for a path in which the United States achieves an energy and CO2 emissions pathway consistent

  8. Thyristor converter simulation and analysis

    SciTech Connect (OSTI)

    Zhang, S.Y.

    1991-01-01T23:59:59.000Z

    In this paper we present a simulation on thyristor converters. The simulation features nonlinearity, non-uniform firing, and the commutations. Several applications such as a current regulation, a converter frequency characteristics analysis, and a power line disturbance analysis will be presented. 4 refs., 4 figs.

  9. Thermionic-photovoltaic energy converter

    SciTech Connect (OSTI)

    Chubb, D. L.

    1985-07-09T23:59:59.000Z

    A thermionic-photovoltaic energy conversion device comprises a thermionic diode mounted within a hollow tubular photovoltaic converter. The thermionic diode maintains a cesium discharge for producing excited atoms that emit line radiation in the wavelength region of 850 nm to 890 nm. The photovoltaic converter is a silicon or galium arsenide photovoltaic cell having bandgap energies in this same wavelength region for optimum cell efficiency.

  10. Converting Biomass to High-Value Feedstocks

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

    Converting Biomass to High-Value Feedstocks Advanced feedstocks play an important role in economically and efficiently converting biomass into bioenergy products. Advanced...

  11. A thermionic converter success story

    SciTech Connect (OSTI)

    Donovan, B.D.; Lamp, T.R. (Aerospace Power Division, Wright Laboratory Wright-Patterson AFB, OH 45433-6563 (United States)); Ramaligam, M.L. (UES, Inc. 4401 Dayton-Xenia Road, Dayton, OH 45432-1894 (United States))

    1993-01-20T23:59:59.000Z

    This paper summarizes the advanced out-of-core thermionic technology program being managed at Wright Laboratory: The Thermionic Critical Technology (TCT) Investigation. This program has been supported primarily by the United State Air Force for design and fabrication, and supported by Strategic Defense Initiative Organization (SDIO) for performance and life testing efforts. Converter design parameters, specifications, and performance testing data is summarized. Converters fabricated by Loral Electro Optical Systems (Loral EOS) under this program have exceeding performance requirements, and have demonstrated efficiencies as high as 14%.

  12. Power converters for parabolic dishes

    SciTech Connect (OSTI)

    Truscello, V.C.; Williams, A.N.

    1981-01-01T23:59:59.000Z

    The development status of receivers and power conversion units to be used with parabolic dish concentrators is presented. Applications are identified, and the key role played by the power converter element of the collector module is emphasized. The electrical output of the 11-meter-diameter dish modules which are being developed varies up to a maximum of about 25 kilowatts, depending on the thermodynamic cycle of the power converter. Three power conversion units are being developed: an organic Rankine, an air Brayton, and a Stirling. The development program for the receivers and the power conversion units is described in detail.

  13. Charge-pump voltage converter

    DOE Patents [OSTI]

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

    2009-11-03T23:59:59.000Z

    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.

  14. Collector for thermionic energy converter

    SciTech Connect (OSTI)

    Bell, R.L.

    1981-07-21T23:59:59.000Z

    An improved collector is provided for a thermionic energy converter. The collector comprises a p-type layer of a semiconductor material formed on an n-type layer of a semiconductor material. The p-n junction is maintained in a forward biased condition. The electron affinity of the exposed surface of the p-type layer is effectively lowered to a low level near zero by the presence of a work function lowering activator. The dissipation of energy during collection is reduced by the passage of electrons through the p-type layer in the metastable conduction band state. A significant portion of the electron current remains at the potential of the fermi level of the n-type layer rather than dropping to the fermi level of the p-type layer. Less energy is therefore dissipated as heat and a higher net power output is delivered from a thermionic energy converter incorporating the collector.

  15. Portable convertible blast effects shield

    DOE Patents [OSTI]

    Pastrnak, John W. (Livermore, CA); Hollaway, Rocky (Modesto, CA); Henning, Carl D. (Livermore, CA); Deteresa, Steve (Livermore, CA); Grundler, Walter (Hayward, CA); Hagler, Lisle B. (Berkeley, CA); Kokko, Edwin (Dublin, CA); Switzer, Vernon A. (Livermore, CA)

    2011-03-15T23:59:59.000Z

    A rapidly deployable portable convertible blast effects shield/ballistic shield includes a set two or more frusto-conically-tapered telescoping rings operably connected to each other to convert between a telescopically-collapsed configuration for storage and transport, and a telescopically-extended upright configuration forming an expanded inner volume. In a first embodiment, the upright configuration provides blast effects shielding, such as against blast pressures, shrapnel, and/or fire balls. And in a second embodiment, the upright configuration provides ballistic shielding, such as against incoming weapons fire, shrapnel, etc. Each ring has a high-strength material construction, such as a composite fiber and matrix material, capable of substantially inhibiting blast effects and impinging projectiles from passing through the shield. And the set of rings are releasably securable to each other in the telescopically-extended upright configuration by the friction fit of adjacent pairs of frusto-conically-tapered rings to each other.

  16. Portable convertible blast effects shield

    DOE Patents [OSTI]

    Pastrnak, John W. (Livermore, CA); Hollaway, Rocky (Modesto, CA); Henning, Carl D. (Livermore, CA); Deteresa, Steve (Livermore, CA); Grundler, Walter (Hayward, CA); Hagler, Lisle B. (Berkeley, CA); Kokko, Edwin (Dublin, CA); Switzer, Vernon A (Livermore, CA)

    2007-05-22T23:59:59.000Z

    A rapidly deployable portable convertible blast effects shield/ballistic shield includes a set two or more telescoping cylindrical rings operably connected to each other to convert between a telescopically-collapsed configuration for storage and transport, and a telescopically-extended upright configuration forming an expanded inner volume. In a first embodiment, the upright configuration provides blast effects shielding, such as against blast pressures, shrapnel, and/or fire balls. And in a second embodiment, the upright configuration provides ballistic shielding, such as against incoming weapons fire, shrapnel, etc. Each ring has a high-strength material construction, such as a composite fiber and matrix material, capable of substantially inhibiting blast effects and impinging projectiles from passing through the shield. And the set of rings are releasably securable to each other in the telescopically-extended upright configuration, such as by click locks.

  17. Portable convertible blast effects shield

    DOE Patents [OSTI]

    Pastrnak, John W. (Livermore, CA); Hollaway, Rocky (Modesto, CA); Henning, Carl D. (Livermore, CA); Deteresa, Steve (Livermore, CA); Grundler, Walter (Hayward, CA); Hagler,; Lisle B. (Berkeley, CA); Kokko, Edwin (Dublin, CA); Switzer, Vernon A (Livermore, CA)

    2010-10-26T23:59:59.000Z

    A rapidly deployable portable convertible blast effects shield/ballistic shield includes a set two or more telescoping cylindrical rings operably connected to each other to convert between a telescopically-collapsed configuration for storage and transport, and a telescopically-extended upright configuration forming an expanded inner volume. In a first embodiment, the upright configuration provides blast effects shielding, such as against blast pressures, shrapnel, and/or fire balls. And in a second embodiment, the upright configuration provides ballistic shielding, such as against incoming weapons fire, shrapnel, etc. Each ring has a high-strength material construction, such as a composite fiber and matrix material, capable of substantially inhibiting blast effects and impinging projectiles from passing through the shield. And the set of rings are releasably securable to each other in the telescopically-extended upright configuration, such as by click locks.

  18. COMMUNITY ALERT INCIDENT: Catalytic Converter Thefts

    E-Print Network [OSTI]

    Rose, Michael R.

    converter is a part used to reduce the toxicity of emissions from an internal combustion engine. What can

  19. CONVERTIBLE BONDS IN A DEFAULTABLE DIFFUSION MODEL

    E-Print Network [OSTI]

    Jeanblanc, Monique

    CONVERTIBLE BONDS IN A DEFAULTABLE DIFFUSION MODEL Tomasz R. Bielecki Department of Applied Research Grant PS12918. #12;2 Convertible Bonds in a Defaultable Diffusion Model 1 Introduction In [4), such as Convertible Bonds (CB), and we provided a rigorous decomposition of a CB into a bond component and a (game

  20. Auxiliary resonant DC tank converter

    DOE Patents [OSTI]

    Peng, Fang Z. (Knoxville, TN)

    2000-01-01T23:59:59.000Z

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

  1. Digital control of HVDC converters

    SciTech Connect (OSTI)

    Pilotto, L.A.S.; Roitman, M.; Alves, J.E.R.

    1989-05-01T23:59:59.000Z

    This paper presents the project of a completely digital HVDC converter controller based on a 16-bit microcomputer. It was decided to achieve as much as possible by software in order to minimize functions performed by external hardware. The presented design comprises software programmed functions such as a PID current control amplifier, voltage dependent current order limiters and an alpha-minimum symmetrization unit, among others. HVDC control principles are briefly reviewed and a detailed description of both the hardware and software structure of the controller is presented. The digital controller was implemented in an HVDC simulator and several dynamic performance tests demonstrated the efficiency of the proposed methodology.

  2. Converting Energy to Medical Progress

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinan antagonist Journal Article: Crystal structureComposite-- Energy,Converting to April 2001 An introduction

  3. Converting Energy to Medical Progress

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed New SubstationCleanCommunity2Workshops01ControllingControls onPolymers -Converting to

  4. A variable parameter thermionic energy converter

    E-Print Network [OSTI]

    Bragg, Bobby Joe

    1967-01-01T23:59:59.000Z

    A VARIABLE PARAMETER THERMIONIC ENERGY CONVERTER A Thesis By Bobby Joe Bragg Submitted to the Graduate School of the Texas A 8c M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE August, 1967 Major... LIST OF FIGURES FIGURE 1. SIMPLE SCHEMATIC OF A THERMIONIC CONVERTER PAGE 2. POWER VS SPACING WITH A MINIMUM POWER POINT 3. POWER VS SPACING WITH NO MINIMUM POWER POINT 4. CONVERTER MOTIVE DIAGRAM~ O'E = 5. CONVERTER MOTIVE DIAGRAM~ 6. CONVERTER...

  5. Thermionic converter emitter support arrangement

    SciTech Connect (OSTI)

    Allen, D.T.

    1990-10-16T23:59:59.000Z

    A support is presented for use in a thermionic converted to support an end of an emitter to keep it out of contact with a surrounding collector while allowing the emitter end to move axially at its temperatures changes. The emitter end is supported by a spring structure that includes a pair of Belleville springs, and the spring structure is supported by a support structure fixed to the housing that includes the collector. The support structure is in the form of a sandwich with a small metal spring-engaging element at the front end, a large metal main support at the rear end that is attached to the housing, and metal main support. The spring structure can include a loose wafer captured between the Belleville springs.

  6. Thermionic converter emitter support arrangement

    SciTech Connect (OSTI)

    Allen, Daniel T. (La Jolla, CA)

    1990-01-01T23:59:59.000Z

    A support is provided for use in a therminonic converter to support an end of an emitter to keep it out of contact with a surrounding collector while allowing the emitter end to move axially as its temperature changes. The emitter end (34) is supported by a spring structure (44) that includes a pair of Belleville springs, and the spring structure is supported by a support structure (42) fixed to the housing that includes the collector. The support structure is in the form of a sandwich with a small metal spring-engaging element (74) at the front end, a larger metal main support (76) at the rear end that is attached to the housing, and with a ceramic layer (80) between them that is bonded by hot isostatic pressing to the metal element and metal main support. The spring structure can include a loose wafer (120) captured between the Belleville springs.

  7. Thermionic converter emitter support arrangement

    DOE Patents [OSTI]

    Allen, Daniel T. (La Jolla, CA)

    1990-01-01T23:59:59.000Z

    A support is provided for use in a thermionic converter to support an end an emitter to keep it out of contact with a surrounding collector while allowing the emitter end to move axially at its temperatures changes. The emitter end (34) is supported by a spring structure (44) that includes a pair of Belleville springs, and the spring structure is supported by a support structure (42) fixed to the housing that includes the collector. The support structure is in the form of a sandwich with a small metal spring-engaging element (74) at the front end, a larger metal main support (76) at the rear end that is attached to the housng, and with a ceramic layer (80) between them that is bonded by hot isostatic pressing to the metal element and metal main support. The spring structure can include a loose wafer (120) captured between the Belleville springs.

  8. Thermionic converter emitter support arrangement

    SciTech Connect (OSTI)

    Allen, D.T.

    1990-05-22T23:59:59.000Z

    This patent describes a support provided for use in a therminonic converter to support an end of an emitter to keep it out of contact with a surrounding collector while allowing the emitter end to move axially as its temperature changes. The emitter end is supported by a spring structure that includes a pair of Belleville springs, and the spring structure is supported by a support structure fixed to the housing that includes the collector. The support structure is in the form of a sandwich with a small metal spring-engaging element at the front end, a larger metal main support at the rear end that is attached to the housing, and with a ceramic layer between them that is bonded by hot isostatic pressing to the metal element and metal main support. The spring structure can include a loose wafer captured between the Belleville springs.

  9. Thermionic converter emitter support arrangement

    SciTech Connect (OSTI)

    Allen, D.T.

    1989-07-06T23:59:59.000Z

    This document discusses a support provided for use in a thermionic converter to support an end of an emitter to keep it out of contact with a surrounding collector while allowing the emitter end to move axially as its temperature changes. The emitter end is supported by a spring structure that includes a pair of Belleville springs, and the spring structure is supported by a support structure fixed to the housing that includes the collector. The support structure is in the form of a sandwich with a small metal spring-engaging element at the front end, a larger metal main support at the rear end that is attached to the housing, and with a ceramic layer between them that is bonded by hot isostatic pressing to the metal element and metal main support. The spring structure can include a loose wafer captured between the Belleville springs. 7 figs.

  10. New Catalyst Converts CO2 to Fuel

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

    New Catalyst Converts CO to Fuel Calculations Run at NERSC Help Confirm University of Illinois Breakthrough September 5, 2014 | Tags: Basic Energy Sciences (BES), Carver,...

  11. Vacuum-insulated catalytic converter

    DOE Patents [OSTI]

    Benson, David K. (Golden, CO)

    2001-01-01T23:59:59.000Z

    A catalytic converter has an inner canister that contains catalyst-coated substrates and an outer canister that encloses an annular, variable vacuum insulation chamber surrounding the inner canister. An annular tank containing phase-change material for heat storage and release is positioned in the variable vacuum insulation chamber a distance spaced part from the inner canister. A reversible hydrogen getter in the variable vacuum insulation chamber, preferably on a surface of the heat storage tank, releases hydrogen into the variable vacuum insulation chamber to conduct heat when the phase-change material is hot and absorbs the hydrogen to limit heat transfer to radiation when the phase-change material is cool. A porous zeolite trap in the inner canister absorbs and retains hydrocarbons from the exhaust gases when the catalyst-coated substrates and zeolite trap are cold and releases the hydrocarbons for reaction on the catalyst-coated substrate when the zeolite trap and catalyst-coated substrate get hot.

  12. Fuel to Burn: Economics of Converting Forest

    E-Print Network [OSTI]

    Fried, Jeremy S.

    Fuel to Burn: Economics of Converting Forest Thinnings to Energy Using BioMax in Southern Oregon E-scale gasification plants that generate electrical energy from forest health thinnings may have the potential; Christensen, Glenn. 2005. Fuel to burn: Economics of converting forest thinnings to energy using Bio

  13. High performance, close-spaced thermionic converters

    SciTech Connect (OSTI)

    Dick, R.S.; Britt, E.J.; Fitzpatrick, G.O.; McVey, J.B.

    1983-08-01T23:59:59.000Z

    Near ideal performance in a Thermionic Energy Converter (TEC) can be obtained using extremely small (< 10 microns) interelectrode spacings. Previous efforts to build such converters have encountered engineering problems. A new type of converter, called SAVTEC (for Self-Adjusting, Versatile Thermionic Energy Converter) has been developed at Rasor Associates, Inc., as a practical way to achieve small spacings. It has been demonstrated to deliver improved performance over conventional, ignited-mode converters. A series of individual SAVTEC's have been built and tested. Two general configurations were built: in the first a single emitter support lead (0.25 mm wire) passes through a hole in the center of the collector, with the emitter being welded to it. In the second three smaller wires replace the center wire and are welded to the emitter perimeter. These converters have shown reliable, temperature controlled spacings of the emitter and collector. Reproducible spacing of 10 microns (0.4 mils) were achieved on several converters. This paper presents details of SAVTEC converter construction and performance, including volt-ampere curves.

  14. Catalytic converter with thermoelectric generator

    SciTech Connect (OSTI)

    Parise, R.J.

    1998-07-01T23:59:59.000Z

    The unique design of an electrically heated catalyst (EHC) and the inclusion of an ECO valve in the exhaust of an internal combustion engine will meet the strict new emission requirements, especially at vehicle cold start, adopted by several states in this country as well as in Europe and Japan. The catalytic converter (CC) has been a most useful tool in pollution abatement for the automobile. But the emission requirements are becoming more stringent and, along with other improvements, the CC must be improved to meet these new standards. Coupled with the ECO valve, the EHC can meet these new emission limits. In an internal combustion engine vehicle (ICEV), approximately 80% of the energy consumed leaves the vehicle as waste heat: out the tail pipe, through the radiator, or convected/radiated off the engine. Included with the waste heat out the tail pipe are the products of combustion which must meet strict emission requirements. The design of a new CC is presented here. This is an automobile CC that has the capability of producing electrical power and reducing the quantity of emissions at vehicle cold start, the Thermoelectric Catalytic Power Generator. The CC utilizes the energy of the exothermic reactions that take place in the catalysis substrate to produce electrical energy with a thermoelectric generator. On vehicle cold start, the thermoelectric generator is used as a heat pump to heat the catalyst substrate to reduce the time to catalyst light-off. Thus an electrically heated catalyst (EHC) will be used to augment the abatement of tail pipe emissions. Included with the EHC in the exhaust stream of the automobile is the ECO valve. This valve restricts the flow of pollutants out the tail pipe of the vehicle for a specified amount of time until the EHC comes up to operating temperature. Then the ECO valve opens and allows the full exhaust, now treated by the EHC, to leave the vehicle.

  15. Converting a Motorcycle to Electric Power

    E-Print Network [OSTI]

    Simcoe, Christopher M.

    2009-12-18T23:59:59.000Z

    Research was conducted to determine how simple and practical it would be to convert a standard gasoline powered motorcycle to electric power. The research involved background investigation of useful concepts in electric powered motorcycles...

  16. New Perspectives on Wave Energy Converter Control 

    E-Print Network [OSTI]

    Price, Alexandra A E

    2009-01-01T23:59:59.000Z

    This work examines some of the fundamental problems behind the control of wave energy converters (WECs). Several new perspectives are presented to aid the understanding of the problem and the interpretation of the ...

  17. MULTILEVEL CONVERTERS - A NEW BREED OF POWER CONVERTERS Jih-Sheng...

    Office of Scientific and Technical Information (OSTI)

    well suited for various renewable energy sources such as fuel cell, photovoltaic, and biomass, etc. Connecting separated dc sources between two converters in a back-to-back...

  18. Power conversion architecture for grid interface at high switching frequency

    E-Print Network [OSTI]

    Lim, Seungbum

    This paper presents a new power conversion architecture for single-phase grid interface. The proposed architecture is suitable for realizing miniaturized ac-dc converters operating at high frequencies (HF, above 3 MHz) and ...

  19. acid residues converted: Topics by E-print Network

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

    Websites Summary: - Resonant converters and related systems, such as piezoelectric transformers, may require a high of resonant converters: a series-resonant parallel-...

  20. ars projekt converted: Topics by E-print Network

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

    Websites Summary: - Resonant converters and related systems, such as piezoelectric transformers, may require a high of resonant converters: a series-resonant parallel-...

  1. angiotensin converting enzyme-3: Topics by E-print Network

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

    Websites Summary: - Resonant converters and related systems, such as piezoelectric transformers, may require a high of resonant converters: a series-resonant parallel-...

  2. angiotensin converting enzyme: Topics by E-print Network

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

    Websites Summary: - Resonant converters and related systems, such as piezoelectric transformers, may require a high of resonant converters: a series-resonant parallel-...

  3. Atargis Energy (TRL 4 System) - Cycloidal Wave Energy Converter...

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

    Atargis Energy (TRL 4 System) - Cycloidal Wave Energy Converter Atargis Energy (TRL 4 System) - Cycloidal Wave Energy Converter Atargis Energy (TRL 4 System) - Cycloidal Wave...

  4. SEP Success Story: State Energy Program Helping Arkansans Convert...

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

    State Energy Program Helping Arkansans Convert to Compressed Natural Gas SEP Success Story: State Energy Program Helping Arkansans Convert to Compressed Natural Gas January 25,...

  5. Converting Sunlight into Fuel | Center for Bio-Inspired Solar...

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

    about Center Center Video Library Bisfuel Picture Gallery Converting Sunlight into Fuel 12 Oct 2012 Converting sunlight into electricity from ASU Research on Vimeo. Interview...

  6. Enterprise converting buses to biodiesel | Department of Energy

    Energy Savers [EERE]

    Enterprise converting buses to biodiesel Enterprise converting buses to biodiesel April 1, 2010 - 6:48pm Addthis Paul Lester Communications Specialist, Office of Energy Efficiency...

  7. Isolated and soft-switched power converter

    DOE Patents [OSTI]

    Peng, Fang Zheng (Knoxville, TN); Adams, Donald Joe (Knoxville, TN)

    2002-01-01T23:59:59.000Z

    An isolated and soft-switched power converter is used for DC/DC and DC/DC/AC power conversion. The power converter includes two resonant tank circuits coupled back-to-back through an isolation transformer. Each resonant tank circuit includes a pair of resonant capacitors connected in series as a resonant leg, a pair of tank capacitors connected in series as a tank leg, and a pair of switching devices with anti-parallel clamping diodes coupled in series as resonant switches and clamping devices for the resonant leg. The power converter is well suited for DC/DC and DC/DC/AC power conversion applications in which high-voltage isolation, DC to DC voltage boost, bidirectional power flow, and a minimal number of conventional switching components are important design objectives. For example, the power converter is especially well suited to electric vehicle applications and load-side electric generation and storage systems, and other applications in which these objectives are important. The power converter may be used for many different applications, including electric vehicles, hybrid combustion/electric vehicles, fuel-cell powered vehicles with low-voltage starting, remote power sources utilizing low-voltage DC power sources, such as photovoltaics and others, electric power backup systems, and load-side electric storage and generation systems.

  8. External ionization mechanisms for advanced thermionic converters

    SciTech Connect (OSTI)

    Hatziprokopiou, M.E.

    1981-01-01T23:59:59.000Z

    This work investigates ion generation and recombination mechanisms in the cesium plasma as they pertain to the advanced mode thermionic energy converter. The changes in plasma density and temperature within the converter have been studied under the influence of several promising auxiliary ionization candidate sources. Three novel approaches of external cesium ion generation have been investigated in some detail, namely vibrationally excited N/sub 2/ as are energy source of ionization of Cs ions in a dc discharge, microwave power as a means of resonant sustenance of the cesium plasma, and ion generation in a pulse N/sub 2/-Cs mixture. The experimental data obtained and discussed in this work show that all three techniques - i.e. the non-LTE high-voltage pulsing, the energy transfer from vibrationally excited diatomic gases, and the external pumping with a microwave power - have considerable promise as schemes in auxiliary ion generation applicable to the advanced thermionic energy converter.

  9. Converting Waste into Clean Renewable Fuel

    E-Print Network [OSTI]

    Converting Waste into Clean Renewable Fuel Presented at TechRealization August 27th, 2008 #12;2 Outline · Introduction to InEnTec · InEnTec's Waste-to-Fuels Technology · Richland Project #12;In conversion options · Conversion of waste into clean transportation fuels (i.e. ethanol, methanol, DME, etc

  10. Hybrid switch for resonant power converters

    DOE Patents [OSTI]

    Lai, Jih-Sheng; Yu, Wensong

    2014-09-09T23:59:59.000Z

    A hybrid switch comprising two semiconductor switches connected in parallel but having different voltage drop characteristics as a function of current facilitates attainment of zero voltage switching and reduces conduction losses to complement reduction of switching losses achieved through zero voltage switching in power converters such as high-current inverters.

  11. Characteristics of two thermionic converters with oxide collectors

    SciTech Connect (OSTI)

    Smith, E.A.; Huffman, F.N.

    1984-08-01T23:59:59.000Z

    Thermionic converters built with selected metal oxide coatings on their collectors have given enhanced performance at interelectrode spacings greater than 0.25 mm. The capability of such converters to operate efficiently at large interelectrode spacings is of interest for in-core thermionic power systems. Performance data are reported from one converter built with a collector having a coating of molybdenum sublimed in oxygen and a second converter containing an oxidized zirconium collector. The molybdenum oxide collector converter demonstrated enhanced performance.

  12. Combustion converter development for topping and cogeneration applications

    SciTech Connect (OSTI)

    Goodale, D.; Lieb, D.; Miskolczy, G.; Moffat, A.

    1983-08-01T23:59:59.000Z

    This paper discusses the development of combustion-heated thermionic converters. Combustion applications pose a materials problem that does not exist for thermionic converters used in the vacuum of outer space. The high-temperature components of a thermionic converter must be protected from the oxidizing terrestrial environment. A layer of silicon carbide provides the most satisfactory protective coating, or ''hot shell,'' for the emitter and lead of a combustion-heated thermionic converter. Four areas of work aimed at developing combustion heated thermionic converters will be discussed: improving the performance of the two-inch torispherical converter, modifications to the converter so that it may be used in multi-converter modules, the construction of a thermionic cogeneration test furnace, and a converter life test in an oil-fired furnace.

  13. Optical analog-to-digital converter

    DOE Patents [OSTI]

    Vawter, G. Allen (Corrales, NM); Raring, James (Goleta, CA); Skogen, Erik J. (Albuquerque, NM)

    2009-07-21T23:59:59.000Z

    An optical analog-to-digital converter (ADC) is disclosed which converts an input optical analog signal to an output optical digital signal at a sampling rate defined by a sampling optical signal. Each bit of the digital representation is separately determined using an optical waveguide interferometer and an optical thresholding element. The interferometer uses the optical analog signal and the sampling optical signal to generate a sinusoidally-varying output signal using cross-phase-modulation (XPM) or a photocurrent generated from the optical analog signal. The sinusoidally-varying output signal is then digitized by the thresholding element, which includes a saturable absorber or at least one semiconductor optical amplifier, to form the optical digital signal which can be output either in parallel or serially.

  14. Heat Pump Water Heater using Solid-State Energy Converters |...

    Energy Savers [EERE]

    Heat Pump Water Heater using Solid-State Energy Converters Heat Pump Water Heater using Solid-State Energy Converters Sheetak will work on developing a full scale prototype of its...

  15. A low-power reconfigurable analog-to-digital converter

    E-Print Network [OSTI]

    Gulati, Kush

    2001-01-01T23:59:59.000Z

    This thesis presents the concept, theory and design of a low power CMOS analog-to-digital converter that can digitize signals over a wide range of bandwidth and resolution with adaptive power consumption. The converter ...

  16. Automated Synthesis Tool for Design Optimization of Power Electronic Converters

    E-Print Network [OSTI]

    Mirjafari, Mehran

    2013-01-09T23:59:59.000Z

    module-integrated photovoltaic inverter is also optimized for efficiency, volume and reliability. An actual converter is constructed using commercial off-the-shelf components. The converter design is chosen as close as possible to a point obtained...

  17. An economical single to three phase converter for induction motors

    E-Print Network [OSTI]

    Di Zerega, Philp Van Uytandaele

    1994-01-01T23:59:59.000Z

    There are several different types of single to three phase converters for induction motors available today. However, many of the presently available phase converters suffer from disadvantages such as high cost or low performance. An economical...

  18. Weekly Wrap-Up: Testing Wind Blades, Converting Carbon Emissions...

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

    Weekly Wrap-Up: Testing Wind Blades, Converting Carbon Emissions, and Eco-Driving Weekly Wrap-Up: Testing Wind Blades, Converting Carbon Emissions, and Eco-Driving July 23, 2010 -...

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

    E-Print Network [OSTI]

    Cañizares, Claudio A.

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

  20. 1. PMU Based RAS for a Hybrid AC/DC System 1.1. Project Team

    E-Print Network [OSTI]

    Li, Husheng

    to minimize the impact of disturbances. It is also an integration of various areas related to CPS these wide area protection schemes. Such schemes are essential to the strategic plan in enabling robustness

  1. E-Print Network 3.0 - ac-dc parallel tie-lines Sample Search...

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

    of controlling inductions motors driven through ACDC... AC inverter through a transformer and an ACDC rectifier The connection line between the rectifier... range...

  2. LM2907LM2917FrequencytoVoltageConverter February 1995

    E-Print Network [OSTI]

    Wedeward, Kevin

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

  3. A transient model for a cesium vapor thermionic converter. [Cs

    SciTech Connect (OSTI)

    El-Genk, M.S.; Murray, C.S.; Chaudhuri, S. (Institute for Space Nuclear Power Studies, Department of Chemical and Nuclear Engineering, The University of New Mexico, Albuquerque, New Mexico (USA))

    1991-01-10T23:59:59.000Z

    This paper presents an analytical model for simulating the transient and steady-state operation of cesium vapor thermionic converters. A parametric analysis is performed to assess the transient response of the converter to changes in fission power and width of interelectrode gap. The model optimizes the converter performance for maximum electric power to the load.(AIP)

  4. Voltage balanced multilevel voltage source converter system

    DOE Patents [OSTI]

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

    1997-01-01T23:59:59.000Z

    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.

  5. Voltage balanced multilevel voltage source converter system

    DOE Patents [OSTI]

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

    1997-07-01T23:59:59.000Z

    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.

  6. Photovoltaic converter having apertured reflective enclosure

    SciTech Connect (OSTI)

    Sinton, R.A.; Swanson, R.M.

    1990-10-02T23:59:59.000Z

    This patent describes a photovoltaic converter. It comprises: a photovoltaic cell having an incident face upon which light is directed to cause photogeneration; an enclosure over the incident face, the wall of the enclosure having a reflective inner surface spaced apart from the incident face to permit light reflected from the incident face to be re-reflected by the inner surface and back to the photovoltaic cell; and an aperture through the wall of the enclosure to permit light to fall directly upon the voltaic cell. The ratio of the area of the aperture to the are of the incident face of the photovoltaic cell is less than about 0.2.

  7. convert program | National Nuclear Security Administration

    National Nuclear Security Administration (NNSA)

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

  8. Relationship Among Efficiency and Output Power of Heat Energy Converters

    E-Print Network [OSTI]

    Alexander Luchinskiy

    2004-09-02T23:59:59.000Z

    Relationship among efficiency and output power of heat-electric energy converters as well as of any converters for transforming of heat energy into any other kind of energy is considered. It is shown, that the parameter efficiency does not determine univocally the output power of a converter. It is proposed to use another parameter for determination of working ability of heat energy converters. It is shown, that high output power can not be achieved by any kind of Stirling-type converters in spite of their high efficiency.

  9. Converting online algorithms to local computation algorithms

    E-Print Network [OSTI]

    Mansour, Yishay; Vardi, Shai; Xie, Ning

    2012-01-01T23:59:59.000Z

    We propose a general method for converting online algorithms to local computation algorithms by selecting a random permutation of the input, and simulating running the online algorithm. We bound the number of steps of the algorithm using a query tree, which models the dependencies between queries. We improve previous analyses of query trees on graphs of bounded degree, and extend the analysis to the cases where the degrees are distributed binomially, and to a special case of bipartite graphs. Using this method, we give a local computation algorithm for maximal matching in graphs of bounded degree, which runs in time and space O(log^3 n). We also show how to convert a large family of load balancing algorithms (related to balls and bins problems) to local computation algorithms. This gives several local load balancing algorithms which achieve the same approximation ratios as the online algorithms, but run in O(log n) time and space. Finally, we modify existing local computation algorithms for hypergraph 2-color...

  10. Integrated Solar Upper Stage (ISUS) thermionic converter string evaluation

    SciTech Connect (OSTI)

    Talbot, G.J.; Ramsey, W.D.; Chao, C.J.

    1998-07-01T23:59:59.000Z

    A serial string of eighth (8) thermionic converters were performance tested at New Mexico Engineering Research Institute (NMERI) by Frank Wyant et al1. The tests results from the second String Thermionic Assembly Research Testbed (START II) produced less than one half the expected power based on individual converter performance tests. Seven of the eight converters were returned to Lockheed Martin Information Systems-EOS for performance evaluation. Six of the seven produced nominal performance while the seventh converter showed a drastic reduction in performance due to a cesium leak to atmosphere. Several models were proposed to explain why the individual converter performance differed so markedly from the START II serial array. This paper discusses the models, evaluates model validity and compares the models with results from a tow converter serial test using of the returned START II converters.

  11. Power Maximization in Wave-Energy Converters Using Sampled -Data Extremum Seeking /

    E-Print Network [OSTI]

    Chen, Tianjia

    2013-01-01T23:59:59.000Z

    Power Maximization in Wave-Energy Converters Using Sampled-design optimization of wave energy converters con- sistingN. Sahinkaya. A review of wave energy converter technology.

  12. E-Print Network 3.0 - advanced power converters Sample Search...

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

    (PO.139) Track: Technical Summary: turbines with partial scale power converter and (ii) wind turbines with full scale power converter... power converter of the DFIG can be...

  13. Abstract- CONVERTING SOUND ENERGY TO ELECTRIC ENERGY

    E-Print Network [OSTI]

    Shalabh Rakesh Bhatnagar (srb

    We all know everywhere there is huge scarcity of energy and for running most of our appliances and to carry out daily work we need electricity. It’s really very difficult to imagine our life without electricity, our life would really stop so there is high need, to produce electricity at faster rate and find some other feasible method to produce electric energy. On the other hand we see that in this modern world there is lot of noise pollution in roads, airports, industries.... Just think if we would be able to convert this NOISE POLLUTION TO ELECTRIC ENERGY....??? Yes this could be made possible let’s see how Scientific explanation:- sound is a mechanical form of energy which travel in the form of wave, mechanical wave that is an oscillation of pressure this pressure created by the

  14. Modular Power Converters for PV Applications

    SciTech Connect (OSTI)

    Ozpineci, Burak [ORNL; Tolbert, Leon M [ORNL

    2012-05-01T23:59:59.000Z

    This report describes technical opportunities to serve as parts of a technological roadmap for Shoals Technologies Group in power electronics for PV applications. There are many different power converter circuits that can be used for solar inverter applications. The present applications do not take advantage of the potential for using common modules. We envision that the development of a power electronics module could enable higher reliability by being durable and flexible. Modules would have fault current limiting features and detection circuits such that they can limit the current through the module from external faults and can identify and isolate internal faults such that the remaining modules can continue to operate with only minimal disturbance to the utility or customer. Development of a reliable, efficient, low-cost, power electronics module will be a key enabling technology for harnessing more power from solar panels and enable plug and play operation. Power electronics for computer power supplies, communication equipment, and transportation have all targeted reliability and modularity as key requirements and have begun concerted efforts to replace monolithic components with collections of common smart modules. This is happening on several levels including (1) device level with intelligent control, (2) functional module level, and (3) system module. This same effort is needed in power electronics for solar applications. Development of modular units will result in standard power electronic converters that will have a lower installed and operating cost for the overall system. These units will lead to increased adaptability and flexibility of solar inverters. Incorporating autonomous fault current limiting and reconfiguration capabilities into the modules and having redundant modules will lead to a durable converter that can withstand the rigors of solar power generation for more than 30 years. Our vision for the technology roadmap is that there is no need for detailed design of new power converters for each new application or installation. One set of modules and controllers can be pre-developed and the only design question would be how many modules need to be in series or parallel for the specific power requirement. Then, a designer can put the modules together and add the intelligent reconfigurable controller. The controller determines how many modules are connected, but it might also ask for user input for the specific application during setup. The modules include protection against faults and can reset it, if necessary. In case of a power device failure, the controller reconfigures itself to continue limited operation until repair which might be as simple as taking the faulty module out and inserting a new module. The result is cost savings in design, maintenance, repair, and a grid that is more reliable and available. This concept would be a perfect fit for the recently announced funding opportunity announcement (DE-FOA-0000653) on Plug and Play Photovoltaics.

  15. Mechanical vibration to electrical energy converter

    DOE Patents [OSTI]

    Kellogg, Rick Allen (Tijeras, NM); Brotz, Jay Kristoffer (Albuquerque, NM)

    2009-03-03T23:59:59.000Z

    Electromechanical devices that generate an electrical signal in response to an external source of mechanical vibrations can operate as a sensor of vibrations and as an energy harvester for converting mechanical vibration to electrical energy. The devices incorporate a magnet that is movable through a gap in a ferromagnetic circuit, wherein a coil is wound around a portion of the ferromagnetic circuit. A flexible coupling is used to attach the magnet to a frame for providing alignment of the magnet as it moves or oscillates through the gap in the ferromagnetic circuit. The motion of the magnet can be constrained to occur within a substantially linear range of magnetostatic force that develops due to the motion of the magnet. The devices can have ferromagnetic circuits with multiple arms, an array of magnets having alternating polarity and, encompass micro-electromechanical (MEM) devices.

  16. Graphene optical-to-thermal converter

    E-Print Network [OSTI]

    Manjavacas, Alejandro; Greffet, Jean-Jacques; de Abajo, F Javier García

    2014-01-01T23:59:59.000Z

    Infrared plasmons in doped graphene nanostructures produce large optical absorption that can be used for narrow-band thermal light emission at tunable frequencies that strongly depend on the doping charge. By virtue of Kirchhoff's law, thermal light emission is proportional to the absorption, thus resulting in narrow emission lines associated with the electrically controlled plasmons of heated graphene. Here we show that realistic designs of graphene plasmonic structures can release over 90% of the emission through individual infrared lines with 1% bandwidth. We examine anisotropic graphene structures in which efficient heating can be produced upon optical pumping tuned to a plasmonic absorption resonance situated in the blue region relative to the thermal emission. An incoherent thermal light converter is thus achieved. Our results open a radically different approach for designing tunable nanoscale infrared light sources.

  17. Design of series-parallel connected thermionic converter arrays

    SciTech Connect (OSTI)

    Mcvey, J.B.; Britt, E.J.; Fitzpatrick, G.O.; Dick, R.S.

    1981-01-01T23:59:59.000Z

    Applications of thermionic converters require that a large number of converters be connected together in a series-parallel array in order to provide a useful output voltage. Such an array also serves to insure a very high overall system reliability, despite possible failures of individual converters. This paper predicts the effects of a nonuniform distribution of input power on the performance of such an array. 9 refs.

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

    SciTech Connect (OSTI)

    None

    2012-02-09T23:59:59.000Z

    Solar ADEPT Project: CU-Boulder is developing advanced power conversion components that can be integrated into individual solar panels to improve energy yields. The solar energy that is absorbed and collected by a solar panel is converted into useable energy for the grid through an electronic component called an inverter. Many large, conventional solar energy systems use one, central inverter to convert energy. CU-Boulder is integrating smaller, microinverters into individual solar panels to improve the efficiency of energy collection. The University’s microinverters rely on electrical components that direct energy at high speeds and ensure that minimal energy is lost during the conversion process—improving the overall efficiency of the power conversion process. CU-Boulder is designing its power conversion devices for use on any type of solar panel.

  19. active npc converter: Topics by E-print Network

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

    Solid State Transformer Engineering Websites Summary: converters as distribution transformers 1. A power electronics-based solid state transformer (SST) providesAc-Ac Dual...

  20. alcohol angiotensin-converting-enzyme inhibitors: Topics by E...

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

    complications. There is no specific treatment for membranous nephropathy. Supportive care with the use of diuretics and angiotensin-converting enzyme inhibitors in combination...

  1. Researchers hope better catalysts lead to better ways of converting...

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

    Researchers hope better catalysts lead to better ways of converting biomass to fuel By Jared Sagoff * August 7, 2013 Tweet EmailPrint ARGONNE, Ill. - Scientists and entrepreneurs...

  2. Ability of Catalytic Converters to Reduce Air Pollution

    E-Print Network [OSTI]

    Nizkorodov, Sergey

    NOx - 1 Ability of Catalytic Converters to Reduce Air Pollution MEASUREMENT OF SELECTED AIR POLLUTANTS IN CAR EXHAUST Last updated: June 17, 2014 #12;NOx - 2 Ability of Catalytic Converters to Reduce Air Pollution MEASUREMENT OF SELECTED AIR POLLUTANTS IN CAR EXHAUST INTRODUCTION Automobile engines

  3. Way to reduce arc voltage losses in hybrid thermionic converters

    SciTech Connect (OSTI)

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

    1982-03-01T23:59:59.000Z

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

  4. The frequency dependent impedance of an HVdc converter

    SciTech Connect (OSTI)

    Wood, A.R.; Arrillaga, J. [Univ. of Canterbury, Christchurch (New Zealand)] [Univ. of Canterbury, Christchurch (New Zealand)

    1995-07-01T23:59:59.000Z

    A linear and direct method of determining the frequency dependent impedance of a 12 pulse HVdc converter is presented. Terms are developed for both the dc and ac side impedances of the converter, including the effect of the firing angle control system, the commutation period, and the variability of the commutation period. The impedance predictions are verified by dynamic simulation.

  5. MATHEMATICAL ANALYSIS OF A WAVE ENERGY CONVERTER ARNAUD ROUGIREL

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    for buoy-type ocean wave energy converter. The simplest model for this scheme is a non autonomous piecewise impact on the environment. In this respect, ocean waves provides a important source of renewable energy. Me- chanical devices that harvest energy stored in ocean waves are called wave energy converter (WEC

  6. A computer program for HVDC converter station RF noise calculations

    SciTech Connect (OSTI)

    Kasten, D.G.; Caldecott, R.; Sebo, S.A. (Ohio State Univ., Columbus, OH (United States). Dept. of Electrical Engineering); Liu, Y. (Virginia Polytechnic Inst. State Univ., Blacksburg, VA (United States). Bradley Dept. of Electrical Engineering)

    1994-04-01T23:59:59.000Z

    HVDC converter station operations generate radio frequency (RF) electromagnetic (EM) noise which could interfere with adjacent communication and computer equipment, and carrier system operations. A generic Radio Frequency Computer Analysis Program (RAFCAP) for calculating the EM noise generated by valve ignition of a converter station has been developed as part of a larger project. The program calculates RF voltages, currents, complex power, ground level electric field strength and magnetic flux density in and around an HVDC converter station. The program requires the converter station network to be represented by frequency dependent impedance functions. Comparisons of calculated and measured values are given for an actual HVDC station to illustrate the validity of the program. RAFCAP is designed to be used by engineers for the purpose of calculating the RF noise produced by the igniting of HVDC converter valves.

  7. Magnet Technology for Power Converters: Nanocomposite Magnet Technology for High Frequency MW-Scale Power Converters

    SciTech Connect (OSTI)

    None

    2012-02-27T23:59:59.000Z

    Solar ADEPT Project: CMU is developing a new nanoscale magnetic material that will reduce the size, weight, and cost of utility-scale PV solar power conversion systems that connect directly to the grid. Power converters are required to turn the energy that solar power systems create into useable energy for the grid. The power conversion systems made with CMU’s nanoscale magnetic material have the potential to be 150 times lighter and significantly smaller than conventional power conversion systems that produce similar amounts of power.

  8. Design and operation of a thermionic converter in air

    SciTech Connect (OSTI)

    Horner, M.H.; Begg, L.L.; Smith, J.N. Jr. [General Atomics, San Diego, CA (United States); Geller, C.B.; Kallnowski, J.E. [Westinghouse Electric Corp., West Mifflin, PA (United States). Bettis Atomic Power Lab.

    1995-01-01T23:59:59.000Z

    An electrically heated thermionic converter has been designed, built and successfully tested in air. Several unique features were incorporated in this converter: an integral cesium reservoir, innovative ceramic-to-metal seals, a heat rejection system coupling the collector to a low temperature heat sink and an innovative cylindrical heater filament. The converter was operated for extended periods of time with the emitter at about 1900 K. the collector at about 700 K, and a power density of over 2 w(e)/sq. cm. Input power transients were run between 50% and 100% thermal power, at up to 1% per second, without instabilities in performance.

  9. Ion trapping in the emitter sheath in thermionic converters

    SciTech Connect (OSTI)

    Lundgren, L.

    1985-12-01T23:59:59.000Z

    The effect of ion trapping in the emitter sheath in ignited thermionic converters is studied. The ion trapping prevents the emitter-sheath barrier from being higher than approximately 0.1 eV, when the current decreases in the converter. This gives a condition for the constriction of the arc. I-V curves are calculated for an ignited thermionic converter with a hydrodynamic plasma theory that takes into account the effect of Coulomb scattering and volume recombination, but assumes that the electron temperature is constant in the plasma.

  10. Prediction of core saturation instability at an HVDC converter

    SciTech Connect (OSTI)

    Burton, R.S. [Teshmont Consultants, Inc., Winnipeg, Manitoba (Canada)] [Teshmont Consultants, Inc., Winnipeg, Manitoba (Canada); Fuchshuber, C.F. [Alberta Power Ltd., Edmonton, Alberta (Canada)] [Alberta Power Ltd., Edmonton, Alberta (Canada); Woodford, D.A. [Manitoba HVDC Research Centre, Winnipeg, Manitoba (Canada)] [Manitoba HVDC Research Centre, Winnipeg, Manitoba (Canada); Gole, A.M. [Univ. of Manitoba, Winnipeg, Manitoba (Canada)] [Univ. of Manitoba, Winnipeg, Manitoba (Canada)

    1996-10-01T23:59:59.000Z

    Core saturation instability has occurred on several HVDC schemes resulting from interactions between second harmonic and dc quantities (voltages and currents) on the ac side of the converter and fundamental frequency quantities on the dc side of the converter. The instability can be reinforced by unbalanced saturation of the converter transformers. The paper presents an analytical method which can be used to quickly screen ac and dc system operating conditions to predict where core saturation instability is likely to occur. Analytical results have been confirmed using the digital transients simulation program PSCAD/EMTDC.

  11. Vehicle Technologies Office Merit Review 2014: WBG Converters and Chargers

    Broader source: Energy.gov [DOE]

    Presentation given by Oak Ridge National Laboratory at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about WBG converters...

  12. Method for converting uranium oxides to uranium metal

    DOE Patents [OSTI]

    Duerksen, Walter K. (Norris, TN)

    1988-01-01T23:59:59.000Z

    A process is described for converting scrap and waste uranium oxide to uranium metal. The uranium oxide is sequentially reduced with a suitable reducing agent to a mixture of uranium metal and oxide products. The uranium metal is then converted to uranium hydride and the uranium hydride-containing mixture is then cooled to a temperature less than -100.degree. C. in an inert liquid which renders the uranium hydride ferromagnetic. The uranium hydride is then magnetically separated from the cooled mixture. The separated uranium hydride is readily converted to uranium metal by heating in an inert atmosphere. This process is environmentally acceptable and eliminates the use of hydrogen fluoride as well as the explosive conditions encountered in the previously employed bomb-reduction processes utilized for converting uranium oxides to uranium metal.

  13. DOE Announces Webinars on the Wave Energy Converter Prize, the...

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

    Best of the Clean Cities Tools and Resources, and More DOE Announces Webinars on the Wave Energy Converter Prize, the Best of the Clean Cities Tools and Resources, and More March...

  14. Sandia National Laboratories: WEC-Sim (Wave Energy Converter...

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

    and Y. Yu, "Preliminary Verification and Validation of WEC-Sim, an Open-Source Wave Energy Converter Design Tool," in Proceedings of OMAE 2014, San Francisco, CA, 2014. 2...

  15. Multilevel Converter Topologies for Utility Scale Solar Photovoltaic Power Systems

    E-Print Network [OSTI]

    Essakiappan, Somasundaram

    2014-04-30T23:59:59.000Z

    and phase angle of the inverter cells is proposed. This improves differential power processing amongst cells while keeping the voltage and current ratings of the devices low. A battery energy storage system for the multilevel PV converter has also been...

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

    E-Print Network [OSTI]

    Song, Wenpeng

    2012-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Duncan, Joseph, 1981-

    2005-01-01T23:59:59.000Z

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

  18. Idaho Application for Permit to Convert a Geothermal Injection...

    Open Energy Info (EERE)

    navigation, search OpenEI Reference LibraryAdd to library Form: Idaho Application for Permit to Convert a Geothermal Injection Well - Form 4003-3 Form Type ApplicationNotice Form...

  19. Protocols for the Equitable Assessment of Marine Energy Converters 

    E-Print Network [OSTI]

    Ingram, David; Smith, George; Bittencourt-Ferreira, Claudio; Smith, Helen

    This book contains the suite of protocols for the equitable evaluation of marine energy converters (based on either tidal or wave energy) produced by the EquiMar consortium led by the University of Edinburgh. These protocols ...

  20. Design issues for high voltage converters for ion engines

    SciTech Connect (OSTI)

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

    1995-12-31T23:59:59.000Z

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

  1. Formation of double-valued sheaths in thermionic converters

    SciTech Connect (OSTI)

    Lundgren, L.

    1983-08-01T23:59:59.000Z

    A theory for the sheath in an ignited thermionic converter is presented. The theory includes the effect of the velocity spread of the particles but the charge-particle collisions are neglected. Conditions for the appearance of a virtual emitter are given. The theory is compared with a beam approximation theory and a hydrodynamic theory. All three theories give almost the same condition for the appearance of a virtual emitter in an ignited thermionic converter.

  2. Bi-directional power control system for voltage converter

    DOE Patents [OSTI]

    Garrigan, N.R.; King, R.D.; Schwartz, J.E.

    1999-05-11T23:59:59.000Z

    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.

  3. 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)

    1999-01-01T23:59:59.000Z

    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.

  4. A New Methodology for Frequency Domain Analysis of Wave Energy Converters with Periodically Varying Physical Parameters

    E-Print Network [OSTI]

    Victoria, University of

    A New Methodology for Frequency Domain Analysis of Wave Energy Converters with Periodically Varying Methodology for Frequency Domain Analysis of Wave Energy Converters with Periodically Varying Physical of Mechanical Engineering) ABSTRACT Within a wave energy converter's operational bandwidth, device operation

  5. An evaluation of a parallel-resonant current-source converter for an electrothermal thruster

    E-Print Network [OSTI]

    Tchamdjou, Aristide-Marie

    1996-01-01T23:59:59.000Z

    The Parallel-Resonant Current-Source Converter promises highly efficient DCDC power conversion. It uses zero-voltage switching to reduce the losses and improve the converter efficiency. The Parallel-Resonant Current-Source Converter has been...

  6. Analysis and design of a high power dc-dc converter

    E-Print Network [OSTI]

    Husain, Iqbal

    1989-01-01T23:59:59.000Z

    rating of this converter is virtually unlimited. Similar converter topologies are used in HVDC power transmission in utility power systems. The rating of these HVDC converters can exceed 1000 MVA. The ac link capacttor. C in the DPC circuit serves...

  7. angiotensin-i converting enzyme: Topics by E-print Network

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

    Websites Summary: - Resonant converters and related systems, such as piezoelectric transformers, may require a high of resonant converters: a series-resonant parallel-...

  8. E-Print Network 3.0 - ad converter system Sample Search Results

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

    Summary: method to reconstruct several classical dc-dc converters, a voltage source inverter (VSI), and a current... introduces some new topologies of dc-dc converters that...

  9. Marine High Voltage Power Conditioning and Transmission System with Integrated Storage DE-EE0003640 Final Report

    SciTech Connect (OSTI)

    Frank Hoffmann, PhD; Aspinall, Rik

    2012-12-10T23:59:59.000Z

    Design, Development, and test of the three-port power converter for marine hydrokinetic power transmission. Converter provides ports for AC/DC conversion of hydrokinetic power, battery storage, and a low voltage to high voltage DC port for HVDC transmission to shore. The report covers the design, development, implementation, and testing of a prototype built by PPS.

  10. ProspectusofCPESMiniConsortiumon PowerManagement(PMC)

    E-Print Network [OSTI]

    Virginia Tech

    on developing precompetitive technologies in the areas of power management for distributed power system architectures, power management, EMI/EMC, power quality, Ac/Dc converters, Dc/Dc converters, POL, more power is consumed by both active and standby systems. Consequently, efficient power management

  11. A Solid Core Heatpipe Reactor with Cylindrical Thermoelectric Converter Modules

    SciTech Connect (OSTI)

    Sayre, Edwin D. [218 Brooke Acres Drive, Los Gatos, CA 95032 (United States); Vaidyanathan, Sam [6663 Pomander Place, San Jose, CA 95120 (United States)

    2006-01-20T23:59:59.000Z

    A nuclear space power system that consists of a solid metal nuclear reactor core with heat pipes carrying energy to a cylindrical thermoelectric converter surrounding each of the heat pipes with a heat pipe radiator surrounding the thermoelectric converter is the most simple and reliable space power system. This means no single point of failure since each heat pipe and cylindrical converter is a separate power system and if one fails it will not affect the others. The heat pipe array in the solid core is designed so that if an isolated heat pipe or even two adjacent heat pipes fail, the remaining heat pipes will still transport the core heat without undue overheating of the uranium nitride fuel. The primary emphasis in this paper is on simplicity, reliability and fabricability of such a space nuclear power source. The core and heat pipes are made of Niobium 1% Zirconium alloy (Nb1Zr), with rhenium lined fuel tubes, bonded together by hot isostatic pressure (HIPing) and with sodium as the heat pipe working fluid, can be operated up to 1250K. The cylindrical thermoelectric converter is made by depositing the constituents of the converter around a Nb1%Zr tube and encasing it in a Nb 1% Zr alloy tube and HIPing the structure to get final bonding and to produce residual compressive stresses in all brittle materials in the converter. A radiator heat pipe filled with potassium that operates at 850K is bonded to the outside of the cylindrical converter for cooling. The solid core heat pipe and cylindrical converter are mated by welding during the final assembly. A solid core reactor with 150 heat pipes with a 0.650-inch (1.65 cm) ID and a 30-inch (76.2 cm) length with an output of 8 Watts per square inch as demonstrated by the SP100 PD2 cell tests will produce about 80 KW of electrical power. An advanced solid core reactor made with molybdenum 47% rhenium alloy, with lithium heat pipes and the PD2 theoretical output of 11 watts per square inch or advanced higher temperature converter to operate at 1350K could produce a greater output of approximately 100KW.

  12. Sub-picosecond Resolution Time-to-Digital Converter

    SciTech Connect (OSTI)

    Ph D, Vladimir Bratov; Ph D, Vladimir Katzman; MS EE, Jeb Binkley

    2006-03-30T23:59:59.000Z

    Time-to-digital converters with sub-picosecond resolutions are needed to satisfy the requirements of time-on-flight measurements of the next generation of high energy and nuclear physics experiments. The converters must be highly integrated, power effective, low cost, and feature plug-and-play capabilities to handle the increasing number of channels (up to hundreds of millions) in future Department of Energy experiments. Current state-off-the-art time-to-digital converter integrated circuits do not have the sufficient degree of integration and flexibility to fulfill all the described requirements. During Phase I, the Advanced Science and Novel Technology Company in cooperation with the nuclear physics division of the Oak Ridge National Laboratory has developed the architecture of a novel time-to-digital converter with multiple channels connected to an external processor through a special interfacing block and synchronized by clock signals generated by an internal phase-locked loop. The critical blocks of the system including signal delay lines and delay-locked loops with proprietary differential delay cells, as well as the required digital code converter and the clock period counter have been designed and simulated using the advanced SiGe120 BiCMOS technological process. The results of investigations demonstrate a possibility to achieve the digitization accuracy within 1ps. ADSANTEC has demonstrated the feasibility of the proposed concept in computer simulations. The proposed system will be a critical component for the next generation of NEP experiments.

  13. Methods for degrading or converting plant cell wall polysaccharides

    DOE Patents [OSTI]

    Berka, Randy (Davis, CA); Cherry, Joel (Davis, CA)

    2008-08-19T23:59:59.000Z

    The present invention relates to methods for converting plant cell wall polysaccharides into one or more products, comprising: treating the plant cell wall polysaccharides with an effective amount of a spent whole fermentation broth of a recombinant microorganism, wherein the recombinant microorganism expresses one or more heterologous genes encoding enzymes which degrade or convert the plant cell wall polysaccharides into the one or more products. The present invention also relates to methods for producing an organic substance, comprising: (a) saccharifying plant cell wall polysaccharides with an effective amount of a spent whole fermentation broth of a recombinant microorganism, wherein the recombinant microorganism expresses one or more heterologous genes encoding enzymes which degrade or convert the plant cell wall polysaccharides into saccharified material; (b) fermenting the saccharified material of step (a) with one or more fermenting microoganisms; and (c) recovering the organic substance from the fermentation.

  14. Power line carrier interference from HVDC converter terminals

    SciTech Connect (OSTI)

    Tatro, P.J.; Adamson, K.A. (New England Power Service Co., Westborough, MA (United States)); Eitzmann, M.A.; Smead, M. (GE Industrial and Power Systems, Schenectady, NY (United States). Power Systems Engineering Dept.)

    1993-07-01T23:59:59.000Z

    Power line carrier (PLC) equipment typically operates in the frequency range from 25 kHz to 300 kHz. Interference studies for HVDC converters usually concentrate on interference from noise sources within this frequency range. However, operating experience at the Sandy Pond converter terminal has indicated that PLC equipment is also susceptible to interference from sources of power system harmonics below the PLC frequency range. Extensive field testing and analytical studies have shown that each PLC circuit has a resonant frequency below the operating frequency. If excited at this resonant frequency, high voltages may exist within the PLC circuit. The resulting saturation of PLC components leads to local generation of radio frequency (RF) noise that interferes with proper operation of PLC circuits. Sources of power system harmonics in the 3-10 kHz range, such as line commutated dc converters, are potential sources of this type of interference.

  15. Method for converting sucrose to .beta.-D-glucose

    DOE Patents [OSTI]

    Simmons, Blake A. (San Francisco, CA); Volponi, Joanne V. (Livermore, CA); Ingersoll, David (Albuquerque, NM); Walker, Andrew (Woodinville, WA)

    2009-07-07T23:59:59.000Z

    Disclosed is an apparatus and method for continuously converting sucrose to .beta.-D-glucose. The method comprises a three-stage enzymatic reactor in which an aqueous solution of sucrose is first converted into a solution of fructose and .alpha.-D-glucose by passing it through a porous, packed column containing an inert media on which invertase is immobilized. This solution is then sent through a second packed column containing glucose isomerase and finally a third packed column containing mutarotase. Solution temperature and pH are adjusted to maximize glucose output.

  16. The important effect of electron reflection on thermionic converter performance

    SciTech Connect (OSTI)

    Rasor, N.S.

    1998-07-01T23:59:59.000Z

    Although only a few percent of high energy electrons are reflected from bare metal surfaces, 20--60% of low energy incident electrons are reflected from thermionic converter electrodes with adsorbed cesium and oxygen. The TECMDL computer model indicates that electron reflection in cesium vapor thermionic converters increases the arc potential drop, offsetting the gain in performance obtainable by lowering the collector work function via the coadsorbed Cs/O layer. The possible suppression of electron reflection by using electrodes with sub-micron surface structure is hypothesized and supported by experimental data obtained by employing a new method for testing in cesium-oxygen vapor.

  17. Rare beneficial mutations can halt Muller's ratchet

    E-Print Network [OSTI]

    Goyal, Sidhartha; Jerison, Elizabeth R; Neher, Richard A; Shraiman, Boris I; Desai, Michael M

    2011-01-01T23:59:59.000Z

    The vast majority of mutations are deleterious, and are eliminated by purifying selection. Yet in finite asexual populations, purifying selection cannot completely prevent the accumulation of deleterious mutations due to Muller's ratchet: once lost by stochastic drift, the most-fit class of genotypes is lost forever. If deleterious mutations are weakly selected, Muller's ratchet turns into a mutational "meltdown" leading to a rapid degradation of population fitness. Evidently, the long term stability of an asexual population requires an influx of beneficial mutations that continuously compensate for the accumulation of the weakly deleterious ones. Here we propose that the stable evolutionary state of a population in a static environment is a dynamic mutation-selection balance, where accumulation of deleterious mutations is on average offset by the influx of beneficial mutations. We argue that this state exists for any population size N and mutation rate $U$. Assuming that beneficial and deleterious mutations ...

  18. Has Driving Come to a Halt?

    Annual Energy Outlook 2013 [U.S. Energy Information Administration (EIA)]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) " ,"ClickPipelines AboutDecember 2005 (Thousand9,0, 1997Environment >7,992000 HighlightsHas Driving Come

  19. Northwest Energy Innovations (TRL 5 6 System)- WETNZ MtiMode Wave Energy Converter Advancement Project

    Broader source: Energy.gov [DOE]

    Northwest Energy Innovations (TRL 5 6 System) - WETNZ MtiMode Wave Energy Converter Advancement Project

  20. High speed bypass Fig. 1. Sub-module of MMC converter

    E-Print Network [OSTI]

    Chaudhary, Sanjay

    Modular Converter for VSC-HVDC Transmission Applications: Control and Operational Aspects Udana N, the multilevel modular converter (MMC), recently introduced for HVDC transmission are discussed. The paper. Keywords-Voltage Source Convert (VSC), Multilevel Modular Converter (MMC), HVDC Transmission, Weak ac

  1. Control and Power Management of Converter Fed Microgrids

    E-Print Network [OSTI]

    Lehn, Peter W.

    1 Control and Power Management of Converter Fed Microgrids Charles K. Sao, Member, IEEE, and Peter in parallel in a VSC fed microgrid. Each current controlled VSC in such a microgrid has its own VPD/FQB controller that sets its current references to regulate the voltage and frequency of a common microgrid bus

  2. Pre-converted nitric oxide gas in catalytic reduction system

    DOE Patents [OSTI]

    Hsiao, Mark C. (Livermore, CA); Merritt, Bernard T. (Livermore, CA); Penetrante, Bernardino M. (San Ramon, CA); Vogtlin, George E. (Fremont, CA)

    1999-01-01T23:59:59.000Z

    A two-stage catalyst comprises an oxidative first stage and a reductive second stage. The first stage is intended to convert NO to NO.sub.2 in the presence of O.sub.2. The second stage serves to convert NO.sub.2 to environmentally benign gases that include N2, CO2, and H.sub.2 O. By preconverting NO to NO.sub.2 in the first stage, the efficiency of the second stage for NO.sub.x reduction is enhanced. For example, an internal combustion engine exhaust is connected by a pipe to a first chamber. An oxidizing first catalyst converts NO to NO.sub.2 in the presence of O.sub.2 and includes platinum/alumina, e.g., Pt/Al.sub.2 O.sub.3 catalyst. A flow of hydrocarbons (C.sub.x H.sub.y) is input from a pipe into a second chamber. For example, propene can be used as a source of hydrocarbons. The NO.sub.2 from the first catalyst mixes with the hydrocarbons in the second chamber. The mixture proceeds to a second reduction catalyst that converts NO.sub.2 to N2, CO2, and H.sub.2 O, and includes a gamma-alumina .gamma.-Al.sub.2 O.sub.3. The hydrocarbons and NO.sub.x are simultaneously reduced while passing through the second catalyst.

  3. Performance Assessment of the Wave Dragon Wave Energy Converter

    E-Print Network [OSTI]

    Hansen, René Rydhof

    Performance Assessment of the Wave Dragon Wave Energy Converter Based on the EquiMar Methodology S of the wave energy sector, device developers are called to provide reliable estimates on power performanceMar, Nissum Bredning, Hanstholm, North Sea, Ekofisk, Wave-to-wire, Wave energy. I. INTRODUCTION The wave

  4. Pre-converted nitric oxide gas in catalytic reduction system

    DOE Patents [OSTI]

    Hsiao, M.C.; Merritt, B.T.; Penetrante, B.M.; Vogtlin, G.E.

    1999-04-06T23:59:59.000Z

    A two-stage catalyst comprises an oxidative first stage and a reductive second stage. The first stage is intended to convert NO to NO{sub 2} in the presence of O{sub 2}. The second stage serves to convert NO{sub 2} to environmentally benign gases that include N{sub 2}, CO{sub 2}, and H{sub 2}O. By preconverting NO to NO{sub 2} in the first stage, the efficiency of the second stage for NO{sub x} reduction is enhanced. For example, an internal combustion engine exhaust is connected by a pipe to a first chamber. An oxidizing first catalyst converts NO to NO{sub 2} in the presence of O{sub 2} and includes platinum/alumina, e.g., Pt/Al{sub 2}O{sub 3} catalyst. A flow of hydrocarbons (C{sub x}H{sub y}) is input from a pipe into a second chamber. For example, propene can be used as a source of hydrocarbons. The NO{sub 2} from the first catalyst mixes with the hydrocarbons in the second chamber. The mixture proceeds to a second reduction catalyst that converts NO{sub 2} to N{sub 2}, CO{sub 2}, and H{sub 2}O, and includes a {gamma}-Al{sub 2}O{sub 3}. The hydrocarbons and NO{sub x} are simultaneously reduced while passing through the second catalyst. 9 figs.

  5. Multi-level converters for three-phase photovoltaic applications

    E-Print Network [OSTI]

    Lehman, Brad

    Multi-level converters for three-phase photovoltaic applications Renato M. Nakagomi, Ye Zhao, Brad a switching matrix device and photovoltaic (PV) panels. The approach is based on the dynamic reconfiguration photovoltaic PV panels. The number of PV panels that are connected to the load can be altered using dynamic

  6. Energy Savings Assessment for Digital-to-Analog Converter Boxes

    SciTech Connect (OSTI)

    Cheung, Hoi Ying Iris; Meier, Alan; Brown, Richard

    2011-01-18T23:59:59.000Z

    The Digital Television (DTV) Converter Box Coupon Program was administered by the U.S. government to subsidize purchases of digital-to-analog converter boxes, with up to two $40 coupons for each eligible household. In order to qualify as Coupon Eligible Converter Boxes (CECBs), these devices had to meet a number of minimum performance specifications, including energy efficiency standards. The Energy Star Program also established voluntary energy efficiency specifications that are more stringent than the CECB requirements. In this study, we measured the power and energy consumptions for a sample of 12 CECBs (including 6 Energy Star labeled models) in-use in homes and estimated aggregate energy savings produced by the energy efficiency policies. Based on the 35 million coupons redeemed through the end of the program, our analysis indicates that between 2500 and 3700 GWh per year are saved as a result of the energy efficiency policies implemented on digital-to-analog converter boxes. The energy savings generated are equivalent to the annual electricity use of 280,000 average US homes.

  7. Introduction to workshop on spectral control and converters

    SciTech Connect (OSTI)

    Wanlass, M.W.; Schwartz, R.J.

    1995-01-05T23:59:59.000Z

    This workshop focused on the portion of the TPV system that involves the photovoltaic energy converter and the spectral control element that affects subband-gap photon energy recovery. The discussion was divided into three major topic areas: status of the technology, status of the infrastructure, and champions of the technology. (AIP) {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

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

    E-Print Network [OSTI]

    Lehman, Brad

    components, including transformers and inductors, significantly influences the overall profiles magnetic core to store the energy in the power transformer. A Flyback converter is a popular choice for low. All the center and outer legs are gapped, and the transformers are integrated into one magnetic core

  9. Cycling firing method for bypass operation of bridge converters

    SciTech Connect (OSTI)

    Zabar, Zivan (99-72 66th Rd., Apt. 9N, Forest Hills, NY 11375)

    1982-01-01T23:59:59.000Z

    The bridge converter comprises a number of switching elements and an electronic logic system which regulated the electric power levels by controlling the firing, i.e., the initiation of the conduction period of the switching elements. Cyclic firing of said elements allows the direct current to bypass the alternating current system with high power factor and negligible losses.

  10. "Black Box" EMC model for Power Electronics Converter Mikael Foissac

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    "Black Box" EMC model for Power Electronics Converter Mikael Foissac Grenoble Electrical be forecasted accurately, in order to avoid disturbance of the complete system. To quantify the EMC behaviour will then illustrate the method on a complete chopper cell. II. BLACK BOX EMC MODEL Any EMC analysis must account

  11. A summary of North American HVDC converter station reliability specifications

    SciTech Connect (OSTI)

    Vancers, I. (ABB Power Systems Inc., Los Angeles, CA (United States)); Hormozi, F.J. (Los Angeles Dept. of Water and Power, CA (United States))

    1993-07-01T23:59:59.000Z

    This paper summarizes Reliability, Availability, and Maintainability (RAM) specifications that were issued for thyristor based HVDC converter stations in service in North America. A total of twenty project specifications are summarized. A detailed summary by project is shown with specific quantitative requirements categorized. Definitions of terms, representative design principles, and formulas used in calculating RAM parameters contained in existing reliability specifications are presented.

  12. Converting Nested Algebra Expressions into Flat Algebra Expressions

    E-Print Network [OSTI]

    Van Gucht, Dirk

    Converting Nested Algebra Expressions into Flat Algebra Expressions JAN PAREDAENS University of Antwerp and DIRK VAN GUCHT Indiana University Nested relations generalize ordinary flat relations by allowing tuple values to be either atomic or set valued. The nested algebra is a generalization of the flat

  13. A/D Converter Jee-Hwan Ryu

    E-Print Network [OSTI]

    Ryu, Jee-Hwan

    A/D , MUX and REFS update #12;Korea University of Technology and Education ADSC=1 of Technology and Education Korea University of Technology and Education A/D converter #12;Korea University of Technology and Education () AD > -> X = 1 Korea University of Technology and Education AD #12;Korea

  14. GAISUS-1 thermionic converter for the integrated solar upper stage

    SciTech Connect (OSTI)

    Begg, L.L.; Heffernan, T.F.; Horner, M.H. [General Atomics, San Diego, CA (United States)

    1997-12-31T23:59:59.000Z

    The Integrated Solar Upper Stage (ISUS) system is a compact orbital transfer vehicle which generates thrust to boost payloads from LEO to higher orbits. It does this by collecting and concentrating solar flux into a sensible thermal storage, graphite receiver which is used to heat hydrogen propellant to temperatures of up to 2500 K. The ISUS receiver also radiates heat into an array of thermionic converters which produce electrical power. The GAISUS-1 thermionic converter is a first generation planar converter designed to produce electrical power when coupled with the ISUS receiver. GAISUS-1 will deliver over 31 W{sub e} at 1900 K. A wrought Re hotshoe accepts radiant heat from the receiver. The back side of the hotshoe forms the emitting surface of the converter. Special attention was paid to optimize the electrical and thermal losses experienced through the sleeve. Triple and single sleeve geometries were thermally modeled and evaluated, resulting in the selection of a single sleeve design. A high temperature metal/ceramic seal isolates the emitter sleeve from the collector. A Nb collector is used and is an integral part of a Nb/Na heat pipe. The heat pipe transports reject heat from the collector surface to a thermal radiator (condenser) portion of the heat pipe. The converter utilizes an integral graphite Cs reservoir. This type of reservoir automatically produces a rise in Cs pressure in response to a rise in emitter/collector temperatures. This Cs pressure feedback mechanism insures adequate Cs coverage of the emitter over a broad range of operating conditions (temperatures).

  15. Wind turbines convert the kinetic energy in moving air into rotational energy, which in turn is converted

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    Wind turbines convert the kinetic energy in moving air into rotational energy, which in turn of electricity wind can make varies constantly. Sometimes a wind turbine will make no power at all is an indicator of how much energy a particular wind turbine makes in a particular place. Continued on page 2 #12

  16. EC417 --Electric Energy, Adapting to Renewable Resources Brief History of Power Systems (the great AC-DC battle)

    E-Print Network [OSTI]

    EC417 -- Electric Energy, Adapting to Renewable Resources Fall 2014 Topics: · Brief History on renewables (solar, wind, fuel cells, biomass) · Analysis methods for 3-phase systems · Real and Reactive to the introduction of renewables (Photovoltaics, wind, etc.) · Development of the "Smart Grid" · Electric Vehicles

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

    E-Print Network [OSTI]

    Tidd, Chad N. (Chad Norman)

    2010-01-01T23:59:59.000Z

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

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

    DOE Patents [OSTI]

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

    2014-10-14T23:59:59.000Z

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

  19. Low work function material development for the microminiature thermionic converter.

    SciTech Connect (OSTI)

    Zavadil, Kevin Robert; Battaile, Corbett Chandler; Marshall, Albert Christian; King, Donald Bryan; Jennison, Dwight Richard

    2004-03-01T23:59:59.000Z

    Thermionic energy conversion in a miniature format shows potential as a viable, high efficiency, micro to macro-scale power source. A microminiature thermionic converter (MTC) with inter-electrode spacings on the order of microns has been prototyped and evaluated at Sandia. The remaining enabling technology is the development of low work function materials and processes that can be integrated into these converters to increase power production at modest temperatures (800 - 1300 K). The electrode materials are not well understood and the electrode thermionic properties are highly sensitive to manufacturing processes. Advanced theoretical, modeling, and fabrication capabilities are required to achieve optimum performance for MTC diodes. This report describes the modeling and fabrication efforts performed to develop micro dispenser cathodes for use in the MTC.

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

    SciTech Connect (OSTI)

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

    2009-02-01T23:59:59.000Z

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

  1. Ultrafast transient grating radiation to optical image converter

    DOE Patents [OSTI]

    Stewart, Richard E; Vernon, Stephen P; Steel, Paul T; Lowry, Mark E

    2014-11-04T23:59:59.000Z

    A high sensitivity transient grating ultrafast radiation to optical image converter is based on a fixed transmission grating adjacent to a semiconductor substrate. X-rays or optical radiation passing through the fixed transmission grating is thereby modulated and produces a small periodic variation of refractive index or transient grating in the semiconductor through carrier induced refractive index shifts. An optical or infrared probe beam tuned just below the semiconductor band gap is reflected off a high reflectivity mirror on the semiconductor so that it double passes therethrough and interacts with the radiation induced phase grating therein. A small portion of the optical beam is diffracted out of the probe beam by the radiation induced transient grating to become the converted signal that is imaged onto a detector.

  2. Development, evaluation, and design applications of an AMTEC converter model

    E-Print Network [OSTI]

    Spence, Cliff Alan

    2002-01-01T23:59:59.000Z

    of performance curves . . . . . . . 90 INTRODUCTION In the recent history of space exploration, space vehicles slated for missions that ventured into deep space, far from the sun, typically relied on Radioisotope Thermoelectric Generator (RTG) power sources... this need is a type of generator that uses technology known as alkali metal thermal-to-electric conversion (AMTEC). This device, like previous thermoelectric power systems, converts thermal energy directly to electricity. Developed at Ford Scientific...

  3. Intensive neutrino source on the base of lithium converter

    E-Print Network [OSTI]

    V. I. Lyashuk; Yu. S Lutostansky

    2015-03-04T23:59:59.000Z

    An intensive antineutrino source with a hard spectrum (with energy up to 13 MeV, average energy 6.5 MeV) can be realized on the base of beta-decay of short living isotope 8Li (0.84 s). The 8Li isotope (generated in activation of 7Li isotope) is a prime perspective antineutrino source owing to the hard antineutrino spectrum and square dependence of cross section on the energy. Up today nuclear reactors are the most intensive neutrino sources. Antineutrino reactor spectra have large uncertainties in the summary antineutrino spectrum at energy E>6 MeV. Use of 8Li isotope allows to decrease sharply the uncertainties or to exclude it completely. An intensive neutron fluxes are requested for rapid generation of 8Li isotope. The installations on the base of nuclear reactors can be an alternative for nuclear reactors as traditional neutron sources. It is possible creation of neutrino sources another in principle: on the base of tandem of accelerators, neutron generating targets and lithium converter. An intensive neutron flux (i.e., powerful neutron source) is requested for realization of considered neutrino sources (neutrino factories). Different realizations of lithium antineutrino sources (lithium converter on the base of high purified 7Li isotope) are discussed: static regime (i.e., without transport of 8Li isotope to the neutrino detector); dynamic regime (transport of 8Li isotope to the remote detector in a closed cycle); an operation of lithium converter in tandem of accelerator with a neutron-producing target on the base of tungsten, lead or bismuth. Different chemical compounds of lithium (as the substance of the converter) are considered. Heavy water solution of LiOD is proposed as a serious alternative to high-pure 7Li in a metallic state.

  4. Intensive neutrino source on the base of lithium converter

    E-Print Network [OSTI]

    V. I. Lyashuk; Yu. S Lutostansky

    2015-04-13T23:59:59.000Z

    An intensive antineutrino source with a hard spectrum (with energy up to 13 MeV, average energy 6.5 MeV) can be realized on the base of beta-decay of short living isotope 8Li (0.84 s). The 8Li isotope (generated in activation of 7Li isotope) is a prime perspective antineutrino source owing to the hard antineutrino spectrum and square dependence of cross section on the energy. Up today nuclear reactors are the most intensive neutrino sources. Antineutrino reactor spectra have large uncertainties in the summary antineutrino spectrum at energy E>6 MeV. Use of 8Li isotope allows to decrease sharply the uncertainties or to exclude it completely. An intensive neutron fluxes are requested for rapid generation of 8Li isotope. The installations on the base of nuclear reactors can be an alternative for nuclear reactors as traditional neutron sources. It is possible creation of neutrino sources another in principle: on the base of tandem of accelerators, neutron generating targets and lithium converter. An intensive neutron flux (i.e., powerful neutron source) is requested for realization of considered neutrino sources (neutrino factories). Different realizations of lithium antineutrino sources (lithium converter on the base of high purified 7Li isotope) are discussed: static regime (i.e., without transport of 8Li isotope to the neutrino detector); dynamic regime (transport of 8Li isotope to the remote detector in a closed cycle); an operation of lithium converter in tandem of accelerator with a neutron-producing target on the base of tungsten, lead or bismuth. Different chemical compounds of lithium (as the substance of the converter) are considered. Heavy water solution of LiOD is proposed as a serious alternative to high-pure 7Li in a metallic state.

  5. Catalyst for converting synthesis gas to liquid motor fuels

    DOE Patents [OSTI]

    Coughlin, Peter K. (Yorktown Heights, NY)

    1986-01-01T23:59:59.000Z

    The addition of an inert metal component, such as gold, silver or copper, to a Fischer-Tropsch catalyst comprising cobalt enables said catalyst to convert synthesis gas to liquid motor fuels at about 240.degree.-370.degree. C. with advantageously reduced selectivity of said cobalt for methane in said conversion. The catalyst composition can advantageously include a support component, such as a molecular sieve, co-catalyst/support component or a combination of such support components.

  6. Low current plasmatron fuel converter having enlarged volume discharges

    DOE Patents [OSTI]

    Rabinovich, Alexander (Swampscott, MA); Alexeev, Nikolai (Moscow, RU); Bromberg, Leslie (Sharon, MA); Cohn, Daniel R. (Chestnut Hill, MA); Samokhin, Andrei (Moscow, RU)

    2009-10-06T23:59:59.000Z

    A novel apparatus and method is disclosed for a plasmatron fuel converter ("plasmatron") that efficiently uses electrical energy to produce hydrogen rich gas. The volume and shape of the plasma discharge is controlled by a fluid flow established in a plasma discharge volume. A plasmatron according to this invention produces a substantially large effective plasma discharge volume allowing for substantially greater volumetric efficiency in the initiation of chemical reactions within a volume of bulk fluid reactant flowing through the plasmatron.

  7. Capacitor-Less VAR Compensator Based on a Matrix Converter

    E-Print Network [OSTI]

    Balakrishnan, Divya Rathna

    2012-02-14T23:59:59.000Z

    greatly contributed to the completion of this work. I owe my gratitude to them for always believing in me and helping me through my academic pursuit. vii NOMENCLATURE VAR Volt-ampere reactive MC 3-phase ac-to-3-phase ac matrix converter v1... [10] ...... 12 10 Equivalent circuit of a capacitor................................................................. 13 11 Basic layout of a 3/3 MC............................................................................ 16 12 Block diagram...

  8. Microsoft PowerPoint - Converting Sustainable Forest Products into Fuel

    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 RankCombustion | Department of EnergyDevelopmentTechnologiesfromScienceSeptember 15, 2008.Converting

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

    E-Print Network [OSTI]

    Neugebauer, Timothy C.

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

  10. Blind calibration of timing skew in time-interleaved analog-to-digital converters

    E-Print Network [OSTI]

    Divi, Vijay

    The performance of time-interleaved analog-to-digital converters is often significantly degraded by timing mismatch errors. We develop methods for performing blind calibration of such converters, i.e., for estimating the ...

  11. Reentry aerodynamic disruption analysis of thermionic reactor-thermo-converter TOPAZ-2

    SciTech Connect (OSTI)

    Grinberg, E.I.; Nikolaev, V.S. (Scientific Production Association Krasnaya Zvezda'', Moscow 115230 (Russian Federation)); Usov, V.A. (RRC Kurchatov Institute'', Moscow 123182 (Russian Federation)); Gafarov, A.A. (Research Institute of Thermal Processes, Moscow (Russian Federation))

    1993-01-15T23:59:59.000Z

    This paper presents preliminary results of analysis for the TOPAZ-2 thermionic converter-reactor aerodynamic disruption during reentry.

  12. Comparison between arc drops in ignited thermionic converters with and without ion reflections at the emitter

    SciTech Connect (OSTI)

    Lundgren, L.

    1985-07-01T23:59:59.000Z

    The output performance of two thermionic energy converters is compared. One converter has a normal emitter, working with zero field at the emitter which is close to the optimum working point, and the other has a low work function emitter and ion reflection at the emitter. A simple model of the plasma and the sheaths shows that a converter working with a low work function emitter and ion reflections gives a worse performance than a similar converter with a normal emitter.

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

    E-Print Network [OSTI]

    Liberzon, Daniel

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

  14. Modeling and Analysis of Hybrid Converters Michael Evzelman Shmuel (Sam) Ben-Yaakov

    E-Print Network [OSTI]

    the characteristics of hybrid converters. Renewable energy sources such as a single PV panel have, in general, a lowModeling and Analysis of Hybrid Converters Michael Evzelman Shmuel (Sam) Ben-Yaakov Power.ee.bgu.ac.il/~pel/ Abstract--A generic behavioral average-circuit model that analyzes hybrid converters that include

  15. Hybrid Control of a Three-Cell Converter Associated to an Inductive Load

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    3519 Hybrid Control of a Three-Cell Converter Associated to an Inductive Load M. Trabelsi, J of the proposed method. - Dynamic Hybrid Systems, Multi-cell converter, Hybrid control, Digital Signal Processing a class of Hybrid Dynamic Systems (HDS). In the field of power electronics, static converters associated

  16. CHARACTERIZING DANGEROUS WAVES FOR OCEAN WAVE ENERGY CONVERTER SURVIVABILITY Justin Hovland

    E-Print Network [OSTI]

    Haller, Merrick

    CHARACTERIZING DANGEROUS WAVES FOR OCEAN WAVE ENERGY CONVERTER SURVIVABILITY Justin Hovland ABSTRACT Ocean Wave Energy Converters (OWECs) operating on the water surface are subject to storms gradient technologies. This paper is focused on Ocean Wave Energy Converters (OWECs) and the need

  17. A Framework for Dynamic Energy Efficiency and Temperature Management

    E-Print Network [OSTI]

    Renau, Jose

    Simulator Battery Bank: 3kW, 120V, 25AH Bidirectional Buck-Boost DC/DC Converter Communications Control/AC Inverter v c c c c Capacitor Bank - 450V, 9400uF Voltage Sensor: LV25P - ± 500V Current Sensor: LA 55-P CB AC/DC DC/AC v c c c c c c MC 5kw 5kw v v AC/DC Battery Simulator Boost DC/DC Sub CB MC CB MCMCv v

  18. EMTP modeling of CIGRE benchmark based HVDC transmission system operating with weak AC systems

    SciTech Connect (OSTI)

    Sood, V.K. [Hydro-Quebec, Varennes, Quebec (Canada); Khatri, V.; Jin, H. [Concordia Univ., Montreal, Quebec (Canada). Dept. of Electrical and Computer Engineering

    1995-12-31T23:59:59.000Z

    An EMTP based study of a CIGRE benchmark based HVDC system operating with weak ac systems is carried out. The modeled system provides a starting point for (a) educators teaching HVDC transmission courses and (b) for utility planners to develop their own low-cost dedicated digital simulators for training purposes. In this paper, modeling details of the ac-dc system, dc converters and control are presented. To validate the control schemes presented, the HVDC system is tested under ac-dc fault conditions. Results obtained from an EMTP-based study under these fault conditions are also presented in this paper.

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

    SciTech Connect (OSTI)

    Abas Goodarzi

    2011-01-31T23:59:59.000Z

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

  20. Close-spaced Knudsen`s mode thermionic converter

    SciTech Connect (OSTI)

    Kucherov, R.Ya.; Nikolaev, Y.V. [Research Inst. of SIA Lutch, Podolsk (Russian Federation)

    1995-12-31T23:59:59.000Z

    It is demonstrated that the Knudsen`s mode of the thermionic converter (TIC) operation can be realized in a TIC with the interelectrode spacing 15{divided_by}30 {mu} and the emitter work function 5{divided_by}5.5 eV at the emitter temperature above 1800 K and cesium vapor pressure 0.5{divided_by}1 tor. With the use of reflective coating applied to the collector, efficiency of such TIC can achieve the level in excess of 30%.

  1. Results from the Microminiature Thermionic Converter Demonstration Testing Program

    SciTech Connect (OSTI)

    King, D.B.; Luke, J.R.; Wyant, F.J.

    1998-10-05T23:59:59.000Z

    Research is in progress to develop microminiature thermionic converters (MTCS) with high energy conversion efficiencies and variable operating temperatures using semiconductor integrated circuit (IC) fabrication methods. The use of IC techniques allows the fabrication of MTCS with cathode to anode spacing of several microns or less and with anode and cathode materials that will have work fimctions ranging from 1 eV to 3 eV. The small cathode to anode spacing and variable electrode work functions should allow the conversion of heat energy to relatively large current densities (up to tens of Amps/cmz) at relatively high conversion efficiencies ( 15-25%).

  2. Experimental investigation of a thermionic converter with developed surface electrodes

    SciTech Connect (OSTI)

    Luke, J.R.; El-Genk, M.S.; Adrian, J.M. [Institute for Space and Nuclear Power Studies/Chemical and Nuclear Engineering Department University of New Mexico, Albuquerque, New Mexico87131 (United States)

    1997-01-01T23:59:59.000Z

    A thermionic converter with developed planar electrode surfaces is designed and tested. One of the electrodes has concentric circular grooves cut into its surface, while the other electrode surface is smooth. The grooves are 0.5 mm deep and 0.5 mm wide, having lands that are 1.0 mm wide. The experimental setup is flexible so that either the smooth or developed surface electrode can be operated as the emitter, with the other operating as the collector. The I-V characteristics and power output are compared for the two electrode arrangements. {copyright} {ital 1997 American Institute of Physics.}

  3. Multichannel analog-digital converter in VEKTOR-CAMAC systemsystems

    SciTech Connect (OSTI)

    Borodyanskii, M.E.

    1986-09-01T23:59:59.000Z

    This paper describes a four-channel analog-digital converter (ADC) that is implemented by large-scale integrated circuits. Resdundancy of signal conversion in intermediate cycles ensures a more accurate conversion result from cycle to cycle. The ADC is fully compatible with the Vektor system and, with slight modifications, is CAMAC compatible. The conversion time of the ADC for one channel is 5 used, the output code is 14-bit binary, the maximum integral nonlinearity is not more than 0.05% of the dynamic range of + or -10V, and the size of the random access memeory is 1024 14-bit words.

  4. Experimental investigation of a thermionic converter with developed surface electrodes

    SciTech Connect (OSTI)

    Luke, James R.; El-Genk, Mohamed S.; Adrian, John M. [Institute for Space and Nuclear Power Studies/Chemical and Nuclear Engineering Department University of New Mexico, Albuquerque, New Mexico 87131 (United States)

    1997-01-10T23:59:59.000Z

    A thermionic converter with developed planar electrode surfaces is designed and tested. One of the electrodes has concentric circular grooves cut into its surface, while the other electrode surface is smooth. The grooves are 0.5 mm deep and 0.5 mm wide, having lands that are 1.0 mm wide. The experimental setup is flexible so that either the smooth or developed surface electrode can be operated as the emitter, with the other operating as the collector. The I-V characteristics and power output are compared for the two electrode arrangements.

  5. Performance testing of the Sandy Pond HVDC converter terminal

    SciTech Connect (OSTI)

    Donahue, J.A.; Fisher, D.A.; Railing, B.D.; Tatro, P.J. (New England Power Service Co., Westborough, MA (United States))

    1993-01-01T23:59:59.000Z

    Results of several performance tests for the 1,800 MW Sandy Pond HVDC converter terminal are presented and discussed. The work progressed during 1990 and 1991 and included tests for power line carrier interference, audible sound, ac and dc line faults and dc harmonic performance. The testing was conducted as part of the commissioning program for the first stage of the Quebec-New England Phase 2 multi-terminal system. In this stage, the Radisson (Quebec) and Sandy Pond (New England) terminals are operational.

  6. Optimal design of AC filter circuits in HVDC converter stations

    SciTech Connect (OSTI)

    Saied, M.M.; Khader, S.A. [Kuwait Univ. (Kuwait). Electrical and Computer Engineering Dept.

    1995-12-31T23:59:59.000Z

    This paper investigates the reactive power as well as the harmonic conditions on both the valve and the AC-network sides of a HVDC converter station. The effect of the AC filter circuits is accurately modeled. The program is then augmented by adding an optimization routine. It can identify the optimal filter configuration, yielding the minimum current distortion factor at the AC network terminals for a prespecified fundamental reactive power to be provided by the filter. Several parameter studies were also conducted to illustrate the effect of accidental or intentional deletion of one of the filter branches.

  7. Harmonic measurements from a group connected generator HVdc converter scheme

    SciTech Connect (OSTI)

    Macdonald, S.J.; Enright, W.; Arrillaga, J. [Univ. of Canterbury, Christchurch (New Zealand)] [Univ. of Canterbury, Christchurch (New Zealand); O`Brien, M.T.

    1995-10-01T23:59:59.000Z

    A recent CIGRE document published in ELECTRA has described the potential benefits of a direct connection of generators to HVdc converters. While many theoretical contributions have been made, no practical test data has become available so far. This paper reports on harmonic tests carried out at the Benmore end of the New Zealand HVdc link operating as a group connected scheme. It was found that the measured harmonic current levels were well below specified generator ratings. Dynamic simulation accurately predicted the harmonic currents whereas the results of a steady state formulation were less reliable.

  8. MHK Technologies/Tide Current Converter | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revision hasInformation Earth's Heat JumpIncMAKGalway Bay IEOWC <SurgeWECSails <Tide Current Converter

  9. Use of a combined lining in copper production converters

    SciTech Connect (OSTI)

    Birkle, G.V.B.; Slovikovski, V.V.; Danilova, T.A.; P'yankova, V.A.; Verzilov, N.A.

    1987-01-01T23:59:59.000Z

    The authors look at materials and methods for increasing the liner life and thermal efficiency of converters used at three copper melting combines in the Soviet Union. The refractories tested are various commercial combinations of magnesite, periclase and chromite, and the properties for which they are tested include their compression strength, heat resistance, thermal expansion, and wear resistance to slag. The authors find the refractory combination least degradable by heat and wear and calculate the savings, both in cost and energy, achieved by the combines in question by the utilization of this liner material.

  10. Converting Methane to Methanol: Structural Insight into the Reaction Center

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed New SubstationCleanCommunity2Workshops01ControllingControls onPolymers -Converting

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

    DOE Patents [OSTI]

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

    1998-01-01T23:59:59.000Z

    A DC-DC converter capable of generating outputs of 100 KV without a transformer comprises a silicon opening switch (SOS) diode connected to allow a charging current from a capacitor to flow into an inductor. When a specified amount of charge has flowed through the SOS diode, it opens up abruptly; and the consequential collapsing field of the inductor causes a voltage and current reversal that is steered into a load capacitor by an output diode. A switch across the series combination of the capacitor, inductor, and SOS diode closes to periodically reset the SOS diode by inducing a forward-biased current.

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

    DOE Patents [OSTI]

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

    1998-06-30T23:59:59.000Z

    A DC-DC converter capable of generating outputs of 100 KV without a transformer comprises a silicon opening switch (SOS) diode connected to allow a charging current from a capacitor to flow into an inductor. When a specified amount of charge has flowed through the SOS diode, it opens up abruptly; and the consequential collapsing field of the inductor causes a voltage and current reversal that is steered into a load capacitor by an output diode. A switch across the series combination of the capacitor, inductor, and SOS diode closes to periodically reset the SOS diode by inducing a forward-biased current. 1 fig.

  13. Robert Nelson Senior Expert Engineering Manager and

    E-Print Network [OSTI]

    McCalley, James D.

    wind turbines Advantages/disadvantages #12;Page 5 Sep 2014 Copyright © Siemens Energy, Inc. 2014. All Breaker Partial AC/DC-DC/AC Converter (30% power rating typical) Supplies rotor winding w/ 3-phase low reserved. Main Advantages Good conversion efficiency Decoupled control of active/reactive power Capable

  14. Advance Three Phase Power Factor Correction Schemes for Utility Interface of Power Electronic Systems

    E-Print Network [OSTI]

    Albader, Mesaad

    2014-07-30T23:59:59.000Z

    systems, battery chargers and data centers etc. Also, high voltage DC (HVDC) systems employ rectifiers to convert ac input to DC output. HVDC is one example of the application of AC/DC conversion, in power system also, grid tie of two different power...

  15. Design and testing of a combustion-heated nineteen-converter SAVTEC array

    SciTech Connect (OSTI)

    Nyren, T.; Fitzpatrick, G.O.; Korringa, M.; McVey, J.; Sahines, T.

    1984-08-01T23:59:59.000Z

    The SAVTEC (Self-Adjusting Versatile Thermionic Energy Converter) is a new design approach for achieving very close (<12..mu..) interelectrode spacing in a thermionic converter. Techniques were developed for fabricating an array of nineteen SAVTEC converters. The array was incorporated in an SiC protective ''hot shell'' which also served as a radiant heat source for the emitter of each converter. The completed assembly was tested with a specially constructed combustion heat source. Electric output was generated by sixteen of the nineteen converters, despite poor thermal contact in a cooling block, which resulted in high collector temperatures. Details of the array design and test results are described.

  16. Analysis of emitter material transport in thermionic converter

    SciTech Connect (OSTI)

    Paramonov, D.V.; El-Genk, M.S. [Institute for Space and Nuclear Power Studies, Chemical and Nuclear Engineering Department, University of New Mexico, Albuquerque, New Mexico 87131 (United States)

    1996-03-01T23:59:59.000Z

    Output power and efficiency of a thermionic converter depend on temperatures, cesiated work functions, and emissivities of electrodes as well as the interelectrode gap size. Operation lifetime of a thermionic converter is directly related to the values as well as the stability of these parameters, which can be seriously altered by the transport of emitter material to the collector during operation. Loss rate of tungsten, a preferred emitter material, by sublimation at typical operating temperatures is small (about 3{times}10{sup 7} atom/cm{sup 2}sec at 2000 K). The loss rate, however, can be several orders of magnitude higher in the presence of gaseous contaminants. Accelerated transport of emitter material to collector surface changes the effective emissivity and work functions of the electrodes, resulting in performance degradation. A phenomenological model was developed to simulate emitter material transport to the collector in the presence of oxygen, water vapor, and carbon oxide contaminants. The model accounts for interaction of these contaminants with both emitter and collector. Model results were in agreement with experimental data and theoretical results of other investigators. An analysis was performed to determine steady-state chemical composition of deposited material onto the collector surface in the presence of H{sub 2}O, O{sub 2}, and H{sub 2} gaseous contaminants. {copyright} {ital 1996 American Institute of Physics.}

  17. Thermionic converters for an Integrated Solar Upper Stage (ISUS)

    SciTech Connect (OSTI)

    Anderson, W.G.; Horner-Richardson, K. [Thermacore, Inc., Lancaster, PA (United States)

    1996-12-31T23:59:59.000Z

    The Integrated Solar Upper Stage (ISUS) is a solar bimodal system which combines thermal propulsion and electric power generation in a single integrated system. A thermionic converter was designed and fabricated for the ISUS system. The ISUS thermionic energy converters differ from previous designs, due to the significant changes in operating temperature prior to and during an eclipse, with the emitter temperature increasing from 1,900 K to 2,200 K, and then back again. A complete thermal and electrical model was developed for a planar diode to determine optimum operating dimensions and parameters. The model includes an overall energy balance for the diode, and changes the interelectrode gap spacing due to thermal expansion of the parts as the emitter and/or collector temperatures change. Cesium pressure can be chosen from an external liquid reservoir, an integral reservoir using cesium intercalated into graphite attached to the collector heat pipe, or optimum cesium pressure. With optimum cesium pressure, the maximum efficiency increases from 14% to 16% as the emitter temperature increases from 1,900 K to 2,200 K. The improvement in efficiency is only 2% as the emitter temperature is increased. Optimum efficiency requires an external, actively controlled liquid reservoir.

  18. TEC as electric generator in an automobile catalytic converter

    SciTech Connect (OSTI)

    Svensson, R. [Chalmers Univ. of Technology, Goeteborg (Sweden); Holmlid, L. [Univ. of Goeteborg (Sweden). Dept. of Physical Chemistry

    1996-12-31T23:59:59.000Z

    Modern cars use more and more electric power due to more on-board electric systems, e.g., ABS brakes, active suspension systems, electric windows, chair adjustment systems and electronic engine control systems. One possible energy source for electricity generation is to use the waste heat from the car`s engine, which generally is as much as 80% of the total energy from the combustion of the gasoline. Maybe the best location to tap the excess heat is the Catalytic Converter (Cat) in the exhaust system or perhaps at the exhaust pipes close to the engine. The Cat must be kept within a certain temperature interval. Large amounts of heat are dissipated through the wall of the Cat. A Thermionic Energy Converter (TEC) in coaxial form could conveniently be located around the ceramic cartridge of the Cat. Since the TEC is a rather good heat insulator before it reaches its working temperature the Cat will reach working temperature faster, and the final temperature of it can be controlled better when encapsulated in a concentric TEC arrangement. It is also possible to regulate the temperature of the Cat and the TEC by controlling the electrical load of the TEC. The possible working temperatures of present and future Cats appear very suitable for the new low work function collector TEC, which has been demonstrated to work down to 470 K.

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

    DOE Patents [OSTI]

    Su, Gui-Jia (Knoxville, TN)

    2008-08-05T23:59:59.000Z

    A circuit and method of providing three dc voltage buses and transforming power between a low voltage dc converter and a high voltage dc converter, by coupling a primary dc power circuit and a secondary dc power circuit through an isolation transformer; providing the gating signals to power semiconductor switches in the primary and secondary circuits to control power flow between the primary and secondary circuits and by controlling a phase shift between the primary voltage and the secondary voltage. The primary dc power circuit and the secondary dc power circuit each further comprising at least two tank capacitances arranged in series as a tank leg, at least two resonant switching devices arranged in series with each other and arranged in parallel with the tank leg, and at least one voltage source arranged in parallel with the tank leg and the resonant switching devices, said resonant switching devices including power semiconductor switches that are operated by gating signals. Additional embodiments having a center-tapped battery on the low voltage side and a plurality of modules on both the low voltage side and the high voltage side are also disclosed for the purpose of reducing ripple current and for reducing the size of the components.

  20. Further testing and development of an 11-watt Stirling converter

    SciTech Connect (OSTI)

    Ross, B.A.; Montgomery, W.L. [Stirling Technology Co., Richland, WA (United States)

    1995-12-31T23:59:59.000Z

    Three previous IECEC papers describe the development of an 11-watt Radioisotope Stirling Generator (RSG) intended for remote power applications. This paper describes more recent testing and development activities. Testing of the engineering model (EM) was performed to determine the effect of heat rejection temperature, thermal input and initial charge pressure on thermal efficiency. Shock testing of the generator included a drop test and 3 hours of testing in a random vibration environment where g{sup 2}/Hz = 0.04. Endurance testing of a complete Stirling converter continues, with over 15,000 maintenance-free operating hours. Endurance testing of critical subsystems and components has achieved 14,000 to 26,000 hours of operation without failure. Minor changes to the RSG prototype design, based on the development of the EM, are described.

  1. NREL Research on Converting Biomass to Liquid Fuels

    ScienceCinema (OSTI)

    None

    2013-05-29T23:59:59.000Z

    Unlike other renewable energy sources, biomass can be converted directly into liquid fuels, called "biofuels," to help meet transportation fuel needs. The two most common types of biofuels are ethanol and biodiesel. Today, ethanol is made from starches and sugars, but at the National Renewable Energy Laboratory (NREL) scientists are developing technology to allow it to be made from cellulose and hemicellulose, the fibrous material that makes up the bulk of most plant matter. Biodiesel is made by combining alcohol (usually methanol) with vegetable oil, animal fat, or recycled cooking grease. It can be used as an additive (typically 20%) to reduce vehicle emissions or in its pure form as a renewable alternative fuel for diesel engines. For a text version of this video visit http://www.nrel.gov/learning/re_biofuels.html

  2. A Study of Radiative Bottomonium Transitions using Converted Photons

    SciTech Connect (OSTI)

    Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; /INFN, Bari /Bari U.; Milanes, D.A.; /INFN, Bari; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; /UC, Berkeley; Koch, H.; Schroeder, T.; /Ruhr U., Bochum; Asgeirsson, D.J.; Hearty, C.; /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /Indian Inst. Tech., Guwahati /Harvard U. /Harvey Mudd Coll. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Paris U., VI-VII /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas Nuclear Corp., Austin /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

    2011-08-15T23:59:59.000Z

    The authors use (111 {+-} 1) million {Upsilon}(3S) and (89 {+-} 1) million {Upsilon}(2S) events recorded by the BABAR detector at the PEP-II B-factory at SLAC to perform a study of radiative transitions betwen bottomonium states using photons that have been converted to e{sup +}e{sup -} pairs by the detector material. They observe {Upsilon}(3S) {yields} {gamma}{chi}{sub b0,2}(1P) decay, make precise measurements of the branching fractions for {chi}{sub b1,2}(1P, 2P) {yields} {gamma}{Upsilon}(1S) and {chi}{sub b1,2}(2P) {yields} {gamma}{Upsilon}(2S) decays, and search for radiative decay to the {eta}{sub b}(1S) and {eta}{sub b}(2S) states.

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

    DOE Patents [OSTI]

    Kotter, Dale K; Novack, Steven D

    2014-09-30T23:59:59.000Z

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

  4. Utilizing zero-sequence switchings for reversible converters

    DOE Patents [OSTI]

    Hsu, John S.; Su, Gui-Jia; Adams, Donald J.; Nagashima, James M.; Stancu, Constantin; Carlson, Douglas S.; Smith, Gregory S.

    2004-12-14T23:59:59.000Z

    A method for providing additional dc inputs or outputs (49, 59) from a dc-to-ac inverter (10) for controlling motor loads (60) comprises deriving zero-sequence components (V.sub.ao, V.sub.bo, and V.sub.co) from the inverter (10) through additional circuit branches with power switching devices (23, 44, 46), transforming the voltage between a high voltage and a low voltage using a transformer or motor (42, 50), converting the low voltage between ac and dc using a rectifier (41, 51) or an H-bridge (61), and providing at least one low voltage dc input or output (49, 59). The transformation of the ac voltage may be either single phase or three phase. Where less than a 100% duty cycle is acceptable, a two-phase modulation of the switching signals controlling the inverter (10) reduces switching losses in the inverter (10). A plurality of circuits for carrying out the invention are also disclosed.

  5. Results from the microminiature thermionic converter demonstration testing program

    SciTech Connect (OSTI)

    King, Donald B.; Wyant, Francis J. [International Nuclear Safety Department, Sandia National Laboratories, MS-0744, Albuquerque, New Mexico 87185 (United States)] Luke, James R. [New Mexico Engineering Research Institute, 901 University Blvd. SE, Albuquerque, New Mexico 87106 (United States)

    1999-01-01T23:59:59.000Z

    Research is in progress to develop microminiature thermionic converters (MTCs) with high energy conversion efficiencies and variable operating temperatures using semiconductor integrated circuit (IC) fabrication methods. The use of IC techniques allows the fabrication of MTCs with cathode to anode spacing of several microns or less and with anode and cathode materials that will have work functions ranging from 1 eV to 3 eV. The small cathode to anode spacing and variable electrode work functions should allow the conversion of heat energy to relatively large current densities (up to tens of Amps/cm{sup 2}) at relatively high conversion efficiencies (15{endash}25{percent}). {copyright} {ital 1999 American Institute of Physics.}

  6. Spring structure for a thermionic converter emitter support arrangement

    DOE Patents [OSTI]

    Allen, D.T.

    1992-03-17T23:59:59.000Z

    A support is provided for use in a thermionic converter to support an end of an emitter to keep it out of contact with a surrounding collector while allowing the emitter end to move axially as its temperature changes. The emitter end is supported by a spring structure that includes a pair of Belleville springs, and the spring structure is supported by a support structure fixed to the housing that includes the collector. The support structure is in the form of a sandwich with a small metal spring-engaging element at the front end, a larger metal main support at the rear end that is attached to the housing, and with a ceramic layer between them that is bonded by hot isostatic pressing to the metal element and metal main support. The spring structure can include a loose wafer captured between the Belleville springs. 7 figs.

  7. Spring structure for a thermionic converter emitter support arrangement

    SciTech Connect (OSTI)

    Allen, Daniel T. (La Jolla, CA)

    1992-01-01T23:59:59.000Z

    A support is provided for use in a thermionic converter to support an end of an emitter to keep it out of contact with a surrounding collector while allowing the emitter end to move axially as its temperature changes. The emitter end (34) is supported by a spring structure (44) that includes a pair of Belleville springs, and the spring structure is supported by a support structure (42) fixed to the housing that includes the collector. The support structure is in the form of a sandwich with a small metal spring-engaging element (74) at the front end, a larger metal main support (76) at the rear end that is attached to the housing, and with a ceramic layer (80) between them that is bonded by hot isostatic pressing to the metal element and metal main support. The spring structure can include a loose wafer (120) captured between the Belleville springs.

  8. Low Head, Vortex Induced Vibrations River Energy Converter

    SciTech Connect (OSTI)

    Bernitsas, Michael B.; Dritz, Tad

    2006-06-30T23:59:59.000Z

    Vortex Induced Vibrations Aquatic Clean Energy (VIVACE) is a novel, demonstrated approach to extracting energy from water currents. This invention is based on a phenomenon called Vortex Induced Vibrations (VIV), which was first observed by Leonardo da Vinci in 1504AD. He called it ‘Aeolian Tones.’ For decades, engineers have attempted to prevent this type of vibration from damaging structures, such as offshore platforms, nuclear fuel rods, cables, buildings, and bridges. The underlying concept of the VIVACE Converter is the following: Strengthen rather than spoil vortex shedding; enhance rather than suppress VIV; harness rather than mitigate VIV energy. By maximizing and utilizing this unique phenomenon, VIVACE takes this “problem” and successfully transforms it into a valuable resource for mankind.

  9. NREL Research on Converting Biomass to Liquid Fuels

    SciTech Connect (OSTI)

    None

    2010-01-01T23:59:59.000Z

    Unlike other renewable energy sources, biomass can be converted directly into liquid fuels, called "biofuels," to help meet transportation fuel needs. The two most common types of biofuels are ethanol and biodiesel. Today, ethanol is made from starches and sugars, but at the National Renewable Energy Laboratory (NREL) scientists are developing technology to allow it to be made from cellulose and hemicellulose, the fibrous material that makes up the bulk of most plant matter. Biodiesel is made by combining alcohol (usually methanol) with vegetable oil, animal fat, or recycled cooking grease. It can be used as an additive (typically 20%) to reduce vehicle emissions or in its pure form as a renewable alternative fuel for diesel engines. For a text version of this video visit http://www.nrel.gov/learning/re_biofuels.html

  10. Third generation development of an 11-watt Stirling converter

    SciTech Connect (OSTI)

    Montgomery, W.L.; Ross, B.A.; Penswick, L.B. [Stirling Technology Co., Kennewick, WA (United States)

    1996-12-31T23:59:59.000Z

    This paper describes recent design enhancements, performance results, and development of an artificial neural network (ANN) model related to the Radioisotope Stirling Generator (RSG), an 11-watt converter designed for remote power applications. Design enhancements include minor changes to improve performance, increase reliability, facilitate fabrication and assembly for limited production, and reduce mass. Innovative modifications were effected to increase performance and improve reliability of the vacuum foil insulation (VFI) package and linear alternator. High and low operating temperature acceptance testing of the Engineering Model (EM) demonstrated the robust system characteristics. These tests were conducted for 1 week of operation each, with rejector temperatures of 95 C and 20 C, respectively. Endurance testing continues for a complete Stirling converter, the Development Model (DM), with over 25,000 hours of maintenance-free operation. Endurance testing of flexures has attained over 540 flexure-years and endurance testing of linear motors/alternators has achieved nearly 27,000 hours of operation without failure. An ANN model was developed and tested successfully on the DM. Rejection temperatures were varied between 3 C and 75 C while load voltages ranged between engine stall and displacer overstroke. The trained ANN model, based solely on externally measured parameters, predicted values of piston amplitude, displacer amplitude, and piston-displacer phase angle within {+-}2% of the measured values over the entire operating regime. The ANN model demonstrated its effectiveness in the long-term evaluation of free-piston Stirling machines without adding the complexity, reduced reliability, and increased cost of sophisticated diagnostic instrumentation.

  11. Reference Model 6 (RM6): Oscillating Wave Energy Converter.

    SciTech Connect (OSTI)

    Bull, Diana L; Smith, Chris; Jenne, Dale Scott; Jacob, Paul; Copping, Andrea; Willits, Steve; Fontaine, Arnold; Brefort, Dorian; Gordon, Margaret Ellen; Copeland, Robert; Jepsen, Richard A.

    2014-10-01T23:59:59.000Z

    This report is an addendum to SAND2013-9040: Methodology for Design and Economic Analysis of Marine Energy Conversion (MEC) Technologies. This report describes an Oscillating Water Column Wave Energy Converter reference model design in a complementary manner to Reference Models 1-4 contained in the above report. In this report, a conceptual design for an Oscillating Water Column Wave Energy Converter (WEC) device appropriate for the modeled reference resource site was identified, and a detailed backward bent duct buoy (BBDB) device design was developed using a combination of numerical modeling tools and scaled physical models. Our team used the methodology in SAND2013-9040 for the economic analysis that included costs for designing, manufacturing, deploying, and operating commercial-scale MEC arrays, up to 100 devices. The methodology was applied to identify key cost drivers and to estimate levelized cost of energy (LCOE) for this RM6 Oscillating Water Column device in dollars per kilowatt-hour (%24/kWh). Although many costs were difficult to estimate at this time due to the lack of operational experience, the main contribution of this work was to disseminate a detailed set of methodologies and models that allow for an initial cost analysis of this emerging technology. This project is sponsored by the U.S. Department of Energy's (DOE) Wind and Water Power Technologies Program Office (WWPTO), within the Office of Energy Efficiency & Renewable Energy (EERE). Sandia National Laboratories, the lead in this effort, collaborated with partners from National Laboratories, industry, and universities to design and test this reference model.

  12. Reference Model 5 (RM5): Oscillating Surge Wave Energy Converter

    SciTech Connect (OSTI)

    Yu, Y. H.; Jenne, D. S.; Thresher, R.; Copping, A.; Geerlofs, S.; Hanna, L. A.

    2015-01-01T23:59:59.000Z

    This report is an addendum to SAND2013-9040: Methodology for Design and Economic Analysis of Marine Energy Conversion (MEC) Technologies. This report describes an Oscillating Water Column Wave Energy Converter (OSWEC) reference model design in a complementary manner to Reference Models 1-4 contained in the above report. A conceptual design for a taut moored oscillating surge wave energy converter was developed. The design had an annual electrical power of 108 kilowatts (kW), rated power of 360 kW, and intended deployment at water depths between 50 m and 100 m. The study includes structural analysis, power output estimation, a hydraulic power conversion chain system, and mooring designs. The results were used to estimate device capital cost and annual operation and maintenance costs. The device performance and costs were used for the economic analysis, following the methodology presented in SAND2013-9040 that included costs for designing, manufacturing, deploying, and operating commercial-scale MEC arrays up to 100 devices. The levelized cost of energy estimated for the Reference Model 5 OSWEC, presented in this report, was for a single device and arrays of 10, 50, and 100 units, and it enabled the economic analysis to account for cost reductions associated with economies of scale. The baseline commercial levelized cost of energy estimate for the Reference Model 5 device in an array comprised of 10 units is $1.44/kilowatt-hour (kWh), and the value drops to approximately $0.69/kWh for an array of 100 units.

  13. Abstract--This paper presents the harmonic analysis of offshore wind farm (OWF) models with full converters

    E-Print Network [OSTI]

    Bak, Claus Leth

    to the transmission system by long HV cables. This generates advantages such as higher power system reliability with an induction generator and a full- scale converter. Full-rated power converter applied in wind turbines is used the converter to find a broad application in the wind power industry. This kind of power converter includes

  14. Solar energy power generators with advanced thermionic converters for spacecraft applications

    SciTech Connect (OSTI)

    Sahin, S.

    1981-01-01T23:59:59.000Z

    This study presents (1) a 50 kW/sub e/ solar energy generator in a geostationary orbit for direct tv-broadcasting and (2) a 10 GW/sub e/ space power plant, with the basic engineering outlines using an advanced thermionic converter proposal given for each. Further, a comparison of the main technical data for the generators with corresponding energy output using (1) advanced thermionic converter and (2) ordinary thermionic converter without auxiliary emitter is shown. 25 refs.

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

    E-Print Network [OSTI]

    Amirabadi, Mahshid

    2013-08-07T23:59:59.000Z

    ) direct drive using wound-field synchronous generator [10]. ...................................................................................................... 6 Figure 6 Dc-dc buck-boost converter: (a) configuration, (b) energizing mode (mode 1), (c...) de-energizing mode (mode 2), (d) voltage and current waveforms ........ 12 Figure 7 An alternative representation of the dc-dc buck-boost converter ...................... 13 Figure 8 Dc-dc ac-link buck-boost converter: configuration, behavior...

  16. E-Print Network 3.0 - analog-to-digital converters Sample Search...

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

    ARCHITECTURE FOR MASKED SUCCESSIVE Summary: performance, low power, and low electromagnetic interference (EMI) analog-to-digital converters (ADCs) has led... and A. Zayegh, "A...

  17. Wet-process dust-collecting apparatus especially for converter exhaust gases

    SciTech Connect (OSTI)

    Baab, H.

    1985-03-19T23:59:59.000Z

    Metallurgical converter gas is scrubbed in a wet-process electrostatic precipitator utilizing a cylindrical housing and axially separated collecting fields which themselves are vertically subdivided.

  18. E-Print Network 3.0 - alpha converting enzyme Sample Search Results

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

    of Bartlett for the underlying "universe" pdf p:unapply(convert(series(exp(x),x0,tay),polynom),x); p : x1 Source: Finner, Helmut - Mathematisches Institut,...

  19. New Family of Multilevel Matrix Converters for Wind Power Applications: Final Report, July 2002 - March 2006

    SciTech Connect (OSTI)

    Erickson, R.; Angkititrakul, S.; Almazeedi, K.

    2006-12-01T23:59:59.000Z

    The goal of this project was to develop a new modular multilevel matrix converter for wind power applications and to demonstrate a working scale model in the laboratory.

  20. angiotensin-converting enzyme levels: Topics by E-print Network

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

    enzyme activity is significantly determined by a gene polymorphism. Homozygous Brown Norway rats have higher plasma angiotensin I-converting enzyme (more) Jalil Milad, Jorge...

  1. Coal-fired furnace for testing of thermionic converters. Topical report

    SciTech Connect (OSTI)

    Not Available

    1980-10-01T23:59:59.000Z

    The development of thermionic converter technology has progressed to make near-term applications interesting. One of these applications is the thermionic topping of a pulverized coal-fired central station powerplant. Up to now, thermionic converters have been flame tested using natural gas as fuel. A new test furnace is required for evaluation of thermionic converters in a coal-fired environment. The design and costs of a facility which adapts a coal-fired furnace built by Foster Wheeler Development Corporation (FWDC) for thermionic converter testing are discussed. Such a facility would be exempt from air pollution regulations because of its low firing rate.

  2. Bibliography on overvoltage protection and insulation coordination of HVDC converter stations, 1979-1989

    SciTech Connect (OSTI)

    Not Available

    1991-04-01T23:59:59.000Z

    This bibliography is a listing of references on the subject of overvoltage protection and insulation coordination of HVDC converter stations, for the years 1979 through 1989.

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

    SciTech Connect (OSTI)

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

    2011-07-01T23:59:59.000Z

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

  4. E-Print Network 3.0 - angiotensin-i-converting enzyme ace Sample...

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

    Macrophage Angiotensin- Summary: of Human Genetics, University of Utah, Salt Lake City, Utah Angiotensin-converting enzyme (ACE) is a pepti... enzyme. Somatic ACE and testis...

  5. E-Print Network 3.0 - angiotensin i-converting enzyme Sample...

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

    angiotensin-converting enzyme (ACE), but no ACE... , University of Utah, Salt Lake City, Utah To investigate the local effects of angiotensin II ... Source: Capecchi, Mario R....

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

    E-Print Network [OSTI]

    Inam, Wardah

    2013-01-01T23:59:59.000Z

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

  7. E-Print Network 3.0 - analog to digital converters Sample Search...

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

    The objective of this lab... is to analyze, construct, and test a four bit weighted resistor digital to analog converter. The required... digital to ... Source: Landers, Robert...

  8. Intensive neutrino source on the base of lithium converter

    E-Print Network [OSTI]

    Lyashuk, V I

    2015-01-01T23:59:59.000Z

    An intensive antineutrino source with a hard spectrum (with energy up to 13 MeV, average energy 6.5 MeV) can be realized on the base of beta-decay of short living isotope 8Li (0.84 s). The 8Li isotope (generated in activation of 7Li isotope) is a prime perspective antineutrino source owing to the hard antineutrino spectrum and square dependence of cross section on the energy. Up today nuclear reactors are the most intensive neutrino sources. Antineutrino reactor spectra have large uncertainties in the summary antineutrino spectrum at energy E>6 MeV. Use of 8Li isotope allows to decrease sharply the uncertainties or to exclude it completely. An intensive neutron fluxes are requested for rapid generation of 8Li isotope. The installations on the base of nuclear reactors can be an alternative for nuclear reactors as traditional neutron sources. It is possible creation of neutrino sources another in principle: on the base of tandem of accelerators, neutron generating targets and lithium converter. An intensive neu...

  9. Advanced Gate Drive for the SNS High Voltage Converter Modulator

    SciTech Connect (OSTI)

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

    2009-05-07T23:59:59.000Z

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

  10. Digital regulation of a phase controlled power converter

    SciTech Connect (OSTI)

    Schultheiss, C.; Haque, T.

    1995-12-01T23:59:59.000Z

    The Relativistic Heavy Ion Collider, now in construction at Brookhaven National Laboratory, will use phase controlled power converters for the main dipole and quadrupole magnet strings. The rectifiers in these power supplies will be controlled by a digital regulator based on the TI 320C30 Digital Signal Processor (DSP). The DSP implements the current loop, the voltage loop, and a system to actively reduce the sub-harmonic ripple components. Digital firing circuits consisting of a phase locked lop and counters are used to fire the SCRs. Corrections for the sub-harmonic reduction are calculated by the DSP and stored in registers in the firing circuit. These corrections are added in hardware, to the over-all firing count provided by the DSP. the resultant count is compared to a reference counter to fire the SCRs. This combination of a digital control system and the digital firing circuits allows the correction of the sub-harmonics in a real-time sense. A prototype of the regulator has been constructed, and the preliminary testing indicates a sub-harmonic reduction of 60 dB.

  11. Fast pulsing of an open research thermionic converter

    SciTech Connect (OSTI)

    Svensson, R. [Coll. of Applied Engineering and Maritime Studies, Goeteborg (Sweden); [Chalmers Univ. of Technology, Goeteborg (Sweden); Holmlid, L. [Univ. of Goeteborg (Sweden). Dept. of Chemistry

    1997-12-31T23:59:59.000Z

    Several experiments concerning anomalous phenomena in an open Thermionic Energy Converter (TEC) have previously been reported. Under certain conditions a very high electron current (back current), flowing from the cold collector to the hot emitter, has been observed. This phenomenon has been studied with various methods. The conclusion is that an excited form of matter, with a very low work function, is located on the collector surface and in the interelectrode space. The matter consists of highly excited cesium atoms in a condensed form, and is referred to as Rydberg matter (RM). The existence of RM has been predicted theoretically by Manykin, et al. The efficiency of the RM TEC varies considerably with parameters such as emitter temperature and collector temperature. There is also a discrepancy between the apparent collector work function when the collector is run as electron emitter and when it is used as an electron collector. From other experiments the authors conclude that negative ions Cs{sup {minus}} will form on the RM surface on the collector. In order to control the effect of possible negative ions, a series of experiments including rapid pulsing of the TEC is in progress. The objective of the pulsing is to use a negative pulse (with respect to the collector) to remove possible negative ions from the RM surface and restore the low work function of the RM surface.

  12. Method of converting environmentally pollutant waste gases to methanol

    SciTech Connect (OSTI)

    Pfingstl, H.; Martyniuk, W.; Hennepin, A. Ill; McNally, T.; Myers, R.; Eberle, L.

    1993-08-03T23:59:59.000Z

    A continuous flow method is described of converting environmentally pollutant by-product gases emitted during the manufacture of silicon carbide to methanol comprising: (a) operating a plurality of batch furnaces of a silicon carbide manufacturing plant thereby producing silicon carbide and emitting by-product gases during the operation of the furnaces; (b) staggering the operation of the batch furnaces to achieve a continuous emission of the by-product gases; (c) continuously flowing the by-product gases as emitted from the batch furnaces directly to a methanol manufacturing plant; (d) cleansing the by-product gases of particulate matter, including removing the element sulfur from the by-product gases, as they are flowed to the methanol manufacturing plant, sufficiently for use of the by-product gases in producing methanol; and (e) immediately producing methanol from the by-product gases at the methanol manufacturing plant whereby the producing of silicon carbide is joined with the producing of methanol as a unified process.

  13. Converting acoustic energy into useful other energy forms

    DOE Patents [OSTI]

    Putterman, Seth J. (Sherman Oaks, CA); Barber, Bradley Paul (Northridge, CA); Hiller, Robert Anthony (Los Angeles, CA); Lofstedt, Ritva Maire Johanna (Los Angeles, CA)

    1997-01-01T23:59:59.000Z

    Sonoluminescence is an off-equilibrium phenomenon in which the energy of a resonant sound wave in a liquid is highly concentrated so as to generate flashes of light. The conversion of sound to light represents an energy amplification of eleven orders of magnitude. The flashes which occur once per cycle of the audible or ultrasonic sound fields can be comprised of over one million photons and last for less 100 picoseconds. The emission displays a clocklike synchronicity; the jitter in time between consecutive flashes is less than fifty picoseconds. The emission is blue to the eye and has a broadband spectrum increasing from 700 nanometers to 200 nanometers. The peak power is about 100 milliWatts. The initial stage of the energy focusing is effected by the nonlinear oscillations of a gas bubble trapped in the liquid. For sufficiently high drive pressures an imploding shock wave is launched into the gas by the collapsing bubble. The reflection of the shock from its focal point results in high temperatures and pressures. The sonoluminescence light emission can be sustained by sensing a characteristic of the emission and feeding back changes into the driving mechanism. The liquid is in a sealed container and the seeding of the gas bubble is effected by locally heating the liquid after sealing the container. Different energy forms than light can be obtained from the converted acoustic energy. When the gas contains deuterium and tritium there is the feasibility of the other energy form being fusion, namely including the generation of neutrons.

  14. Ancillary Frequency Control of Direct Drive Full-Scale Converter Based Wind Power Plants

    E-Print Network [OSTI]

    Chen, Zhe

    presents a simulation model of a wind power plant based on a MW-level variable speed wind turbineAncillary Frequency Control of Direct Drive Full-Scale Converter Based Wind Power Plants Weihao Hu with a full-scale back-to-back power converter developed in the simulation tool of DIgSILENT Power Factory

  15. Application of wave generator theory to the development of a Wave Energy Converter

    E-Print Network [OSTI]

    Wood, Stephen L.

    Application of wave generator theory to the development of a Wave Energy Converter by Maila Sepri approve the attached thesis Application of wave generator theory to the development of a Wave Energy Application of wave generator theory to the development of a Wave Energy Converter by Maila Sepri Principal

  16. MODULAR MULTI-LEVEL CONVERTER BASED HVDC SYSTEM FOR GRID CONNECTION OF OFFSHORE WIND

    E-Print Network [OSTI]

    Chaudhary, Sanjay

    MODULAR MULTI-LEVEL CONVERTER BASED HVDC SYSTEM FOR GRID CONNECTION OF OFFSHORE WIND POWER PLANT U off-shore wind power plants. The MMC consists of a large number of simple voltage sourced converter offshore wind power plants (WPP) because they offer higher energy yield due to a superior wind profile

  17. The Valuation of Convertible Bonds With Credit Risk P. A. Forsyth K. R. Vetzal

    E-Print Network [OSTI]

    Forsyth, Peter A.

    The Valuation of Convertible Bonds With Credit Risk E. Ayache P. A. Forsyth K. R. Vetzal April 22 upon the history of its stock price. This paper explores the valuation of convertible bonds subject implicit method to decou- ple the system of linear complementarity problems at each timestep. Numerical

  18. A Dual-Supply Buck Converter with Improved Light-Load Efficiency

    E-Print Network [OSTI]

    Zhang, Chao

    2012-07-16T23:59:59.000Z

    to the switching losses that do not scale with load current. In this research, a novel technique for buck converter is proposed to reduce the switching loss by reducing the effective voltage supply at light load. This buck converter, implemented in TSMC 0...

  19. Sliding Mode Control of Boost Converter: Application to energy storage system via supercapacitors

    E-Print Network [OSTI]

    Boyer, Edmond

    Sliding Mode Control of Boost Converter: Application to energy storage system via supercapacitors», «Robust control», «Supercapacitor». Abstract Sliding mode control of boost converter is studied. In order of an energy storage system based on supercapacitors technology in order to regulate the output voltage. Given

  20. Design of a Boost Power Factor Correction Converter Using Optimization Techniques Sergio Busquets-Monge1

    E-Print Network [OSTI]

    Lindner, Douglas K.

    -end converter with an input electromagnetic interference filter. The system design variables are first correction, boost, electromagnetic interference, electromagnetic compatibility. Paper presented at PESC, June of a boost power factor correction front-end converter with an input electromagnetic interference filter

  1. May, 2010DC/DC CONVERTER FOR A SMALL SCALE WIND HYDROGEN SYSTEM

    E-Print Network [OSTI]

    Joel M. Jacobs; Joel M. Jacobs; Joel Michael Jacobs; Adviser Jerry; L. Hudgins

    An electronic converter is designed for an isolated renewable energy system. In this system, energy produced by a small wind turbine is used to extract hydrogen from water. Unique aspects of this application that affect the performance of the converter will be defined. Design considerations of the individual components will be discussed. Calculations on performance and validation of those calculations are also presented.

  2. A Passivity-Based Controller for coordination of converters in a Fuel Cell System

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    and hybrid vehicles has increased since 2009. In this context, the development of a fuel cell (FC) system, , A Passivity-Based Controller for coordination of converters in a Fuel Cell System M. Hilaireta-mail: mickael.hilairet@lgep.supelec.fr Abstract The problem of converters coordination of a fuel cell system

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

    E-Print Network [OSTI]

    Gopinath, Rajesh

    2001-01-01T23:59:59.000Z

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

  4. Regenerative Braking for an Electric Vehicle Using Ultracapacitors and a Buck-Boost Converter

    E-Print Network [OSTI]

    Catholic University of Chile (Universidad Católica de Chile)

    Regenerative Braking for an Electric Vehicle Using Ultracapacitors and a Buck-Boost Converter Juan for an Electric Vehicle has been simulated. The purpose of this device is to allow higher accelerations, similar in shape and size to a Chevrolet S-10. This vehicle was already converted to an electric car

  5. Multi-Stage Converters: A New Technology for Traction Drive Juan W. Dixon

    E-Print Network [OSTI]

    Catholic University of Chile (Universidad Católica de Chile)

    demonstrated the feasibility to build multi-stage converters for real electric vehicles or electric buses of electric vehicles. On the other hand, the PWM techniques used today to control modern static converters of Electrical Engineering Pontificia Universidad Católica de Chile Felipe Ríos, and Alberto Bretón Department

  6. Real-Time Simulation of Matrix Converter Drives **The University of Wisconsin-

    E-Print Network [OSTI]

    Lipo, Thomas

    IGBT/GTO/MOSFET firing pulses from high performance I/O thus permitting matrix converter controller with diodes (except in the case of RB-IGBT). An input filter and voltage clamp circuit complete the circuit Matrix converter a b c u v w Clamp circuit Inductive load Sawp Bi-directional switch on off iu iv iw Fig

  7. Ac-Ac Dual Active Bridge Converter for Solid State Transformer

    E-Print Network [OSTI]

    Kimball, Jonathan W.

    flow. The advantages of direct ac-ac conversion include fewer power conversion stages and minimized single-stage direct ac-ac power conversion to an SST. Fewer conversion stages reduce conduction loss) converter in direct ac-ac power conversion. Like a DAB converter as dc-dc power supply in [5] and [6

  8. The method of creating a small interelectrode spacing in thermionic energy converters

    SciTech Connect (OSTI)

    Kalandarishvili, A.G. [Russian Research Center Kurchatov Inst., Moscow (Russian Federation)

    1996-12-31T23:59:59.000Z

    The method is proposed for creating a small interelectrode spacing in thermionic energy converters (TEC) using graphite-based laminated structures placed inside the converter interelectrode gap. The paper discusses conceptual design and fabrication technology of this device. The proposed method is compared with the methods currently implemented in practice.

  9. All optical gray code to BCD converter e-mail : nkpark@plaza.snu.ac.kr

    E-Print Network [OSTI]

    Park, Namkyoo

    [. 1] / [ 2] / All optical gray code to BCD converter *1) , 2) , 2) , 2) , 1) 1) , 2 to binary-coded-decimal (BCD) converter for the first time in our knowledge utilizing cross gain modulations-level-simplification-method that has been used in electronics, we successfully designed the 4-bit all-optical Gray- code to BCD

  10. Solar Power To Help Convert Carbon Dioxide Into Fuel : Renewable Energy News

    E-Print Network [OSTI]

    Lovley, Derek

    Solar Power To Help Convert Carbon Dioxide Into Fuel : Renewable Energy News TUESDAY 25 MAY, 2010 | | Solar Power To Help Convert Carbon Dioxide Into Fuel by Energy Matters Microbiologist Derek Lovley of energy, the solar panels, can also harvest energy 100 times more effectively than plants. Other

  11. Coordination of Converter and Fuel Cell Controllers Kyung-Won Suh and Anna G. Stefanopoulou

    E-Print Network [OSTI]

    Stefanopoulou, Anna

    , such as an air delivery system which supplies oxygen using a compressor or a blower, a hydrogen delivery system with a compressor and a DC-DC converter. We then employ model-based control techniques to tune two separate controllers for the compressor and the converter. We demonstrate that the lack of communication

  12. Boost Converter Provides Temperature-Controlled Operation of 12V Fan from +5V Supply

    E-Print Network [OSTI]

    McNeill, John A.

    enclosure, and reducing the fan supply voltage when maximum cooling is not necessary. Reducing the operatingBoost Converter Provides Temperature-Controlled Operation of 12V Fan from +5V Supply John Mc converter shown in Fig. 1 allows operation of a 12V brushless DC fan from a +5V supply. The circuit is based

  13. SINGULAR PERTURBATION CONTROL FOR COORDINATION OF CONVERTERS IN A FUEL CELL SYSTEM

    E-Print Network [OSTI]

    - In this paper, the converters coordination problem of a fuel cell system involving a hydrogen fuel cell (FC the problem of the power management of an hydrogen Fuel Cell (FC) system associated to a reversible impulseSINGULAR PERTURBATION CONTROL FOR COORDINATION OF CONVERTERS IN A FUEL CELL SYSTEM M. Ghanes1 , M

  14. The Effects of Wave Energy Converters on a Monochromatic Wave Climate

    E-Print Network [OSTI]

    Fox-Kemper, Baylor

    available from the National Oceanic and Atmospheric Administration (NOAA). Wave energy converters were converters as well as the availability of energy in the ocean. This study will examine the effects of a wave and mean wave period of wave energy fields. There is tremendous energy potential in the ocean. Solar energy

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

    DOE Patents [OSTI]

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

    2014-09-09T23:59:59.000Z

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

  16. Ga{sub x}In{sub 1{minus}x}As thermophotovoltaic converters

    SciTech Connect (OSTI)

    Wanlass, M.W.; Ward, J.S.; Emery, K.A.; Coutts, T.J. [National Renewable Energy Lab., Golden, CO (United States)

    1994-12-31T23:59:59.000Z

    Preliminary research into the development of single-junction Ga{sub x}In{sub 1{minus}x}As thermophotovoltaic (TPV) power converters is reviewed. The devices structures are grown epitaxially on single-crystal InP substrates. Converter band gaps of 0.50--0.74 eV have been considered in accordance with modeling calculations. A 1-sun, AMO efficiency of 12.8% is reported for a lattice-matched, 0.74-eV converter. Converters with lower band gaps are fabricated using lattice-mismatched, compositionally graded structures. Functional TPV converters with good performance characteristics have been demonstrated for band gaps as low as 0.5 eV.

  17. Effective switching frequency multiplier inverter

    DOE Patents [OSTI]

    Su, Gui-Jia (Oak Ridge, TN); Peng, Fang Z. (Okemos, MI)

    2007-08-07T23:59:59.000Z

    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.

  18. Traction Drive System for Electric Vehicles, Using Multilevel Converters Juan W. Dixon, Micah Ortzar and Felipe Ros

    E-Print Network [OSTI]

    Catholic University of Chile (Universidad Católica de Chile)

    Traction Drive System for Electric Vehicles, Using Multilevel Converters Juan W. Dixon, Micah converters for electric vehicles using multilevel inverters. They are being compared with inverters using. Introduction Power Electronics technologies contribute with important part in the development of electric

  19. Numeric simulation of thyristor power converters taking into consideration the firing-circuits and the closed-loop control

    E-Print Network [OSTI]

    Bordry, Frederick; Proudlock, Paul

    1988-01-01T23:59:59.000Z

    Numeric simulation of thyristor power converters taking into consideration the firing-circuits and the closed-loop control

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

    SciTech Connect (OSTI)

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

    1994-05-01T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    2012-09-01T23:59:59.000Z

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

  2. MULTILEVEL INVERTER, BASED ON MULTI-STAGE CONNECTION OF THREE-LEVEL CONVERTERS, SCALED IN POWER OF THREE.

    E-Print Network [OSTI]

    Catholic University of Chile (Universidad Católica de Chile)

    MULTILEVEL INVERTER, BASED ON MULTI-STAGE CONNECTION OF THREE-LEVEL CONVERTERS, SCALED IN POWER. #12;MULTILEVEL INVERTER, BASED ON MULTI-STAGE CONNECTION OF THREE-LEVEL CONVERTERS, SCALED IN POWER, Concepción, Chile ABSTRACT A multi-stage inverter using three-state converters is being analyzed

  3. A Virtual DSP System for Design Instruction of Power Converters AA.. KKeeyyhhaannii aanndd MM.. NN.. MMaarrwwaallii GGeerraalldd BBaauummggaarrttnneerr

    E-Print Network [OSTI]

    Baumgartner, Gerald

    as a case study for the development of the testbed. The resonant power converters provide efficient electric `hard' switching power converters, a resonant converter utilizes a controlled series or parallel LC substantially reduce the switching losses occurred in the power transfer process Despite their attractiveness

  4. Design optimization methodology for power converters based on global energy requirement criteria. Application to a DC-DC flyback structure

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    for power electronic converters according to the Global Energy Requirement (GER) criterion, i.e. the primary-design converters in order to take its environmental impacts (here, only its global primary energy consumptionDesign optimization methodology for power converters based on global energy requirement criteria

  5. Under U.S.-Russia Partnership, Final Shipment of Fuel Converted...

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

    U.S.-Russia Partnership, Final Shipment of Fuel Converted From 20,000 Russian Nuclear Warheads Arrives in United States and Will Be Used for U.S. Electricity Under U.S.-Russia...

  6. Mixed ionic and electronic conducting electrode studies for an alkali metal thermal to electric converter

    E-Print Network [OSTI]

    Guo, Yuyan

    2009-05-15T23:59:59.000Z

    This research focuses on preparation, kinetics, and performance studies of mixed ionic and electronic conducting electrodes (MIEE) applied in an alkali metal thermal to electric converter (AMTEC). Two types of MIEE, metal/sodium titanate and metal...

  7. Request for Information Regarding a Proposed Funding Opportunity for Administration of the Wave Energy Converter Prize

    Broader source: Energy.gov [DOE]

    This announcement is intended to serve as a Notice of Intent of the upcoming Funding Opportunity Announcement (FOA) regarding Administration of the Wave Energy Converter (WEC) Prize and Request for Information.

  8. Request for Information Regarding a Proposed Funding Opportunity for Administration of the Wave Energy Converter Prize

    Broader source: Energy.gov [DOE]

    This announcement is intended to serve as a Notice of Intent of the upcoming Funding Opportunity Announcement (FOA) regarding Administration of the Wave Energy Converter (WEC) Prize and Request for Information to solicit information regarding pote

  9. Research Projects to Convert Captured CO2 Emissions to Useful Products

    Broader source: Energy.gov [DOE]

    Research to help find ways of converting into useful products CO2 captured from emissions of power plants and industrial facilities will be conducted by six projects announced today by the U.S. Department of Energy.

  10. Effect of a nonlinear power take off on a wave energy converter 

    E-Print Network [OSTI]

    Bailey, Helen Louise

    2011-11-22T23:59:59.000Z

    This thesis is titled The influence of a nonlinear Power Take Off on a Wave Energy Converter. It looks at the effect that having a nonlinear Power Take Off (PTO) has on an inertial referenced, slack moored, point absorber, ...

  11. Quantification of the influence of directional sea state parameters over the performances of wave energy converters 

    E-Print Network [OSTI]

    Pascal, Remy Claude Rene

    2012-11-29T23:59:59.000Z

    Accurate predictions of the annual energy yield from wave energy converters are essential to the development of the wave industry. The current method based on power matrices uses only a small part of the data available ...

  12. Generic and Unified Model of Switched Capacitor Converters Sam Ben-Yaakov

    E-Print Network [OSTI]

    Capacitor Converters (SCC) suffer from a fundamental power loss deficiency which makes their use in some applications prohibitive. The power loss is due to the inherent energy dissipation when a capacitor is charged

  13. Area Efficient D/A Converters For Accurate DC Operation Brandon Royce Greenley

    E-Print Network [OSTI]

    Moon, Un-Ku

    . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 6.2 Mismatch Modeling For Area Optimization . . . . . . . . . . . . . . . . . . . . . . . 51 6Area Efficient D/A Converters For Accurate DC Operation by Brandon Royce Greenley A THESIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 5.1 Measurement Setup

  14. Progress on Converting a NIF Quad to Eight, Petawatt Beams for Advanced Radiography

    SciTech Connect (OSTI)

    Crane, J K

    2009-10-19T23:59:59.000Z

    We are converting a quad of NIF beamlines into eight, short-pulse (1-50 ps), petawatt-class beams for advanced radiography and fast ignition experiments. This paper describes progress toward completing this project.

  15. A resonant load circuit to develop electrical power transfer of thermionic converters

    SciTech Connect (OSTI)

    Perez, G.; Estrada, C.A.; Jimenez, A.E.

    1998-07-01T23:59:59.000Z

    Low internal impedance of thermionic converters requires a low impedance load in the DC mode to obtain optimal power transfer. An internal resistance near 0.1 W for thermionic converters is common. According to the maximum power theorem [Desoer,1969], a similar magnitude for the resistance load must be fixed. Due to temperature changes, the internal plasma resistance and the resistance of the leads is modified [Houston,1959], for this reason, it is difficult to maintain maximum power transfer to the load. This paper presents a resonant load circuit for thermionic converters in the AC mode, to develop impedance coupling. The circuit employs an electrical transformer and positive feedback; by this way, oscillations are themselves maintained. It is used an electrical circuit model [Perez et al, 1997], to simulate the electrical behavior of the thermionic converter.

  16. Fabrication and Testing of Full-Length Single-Cell Externally Fueled Converters for Thermionic Reactors

    SciTech Connect (OSTI)

    Schock, Alfred

    1995-08-01T23:59:59.000Z

    Paper presented at the 29th IECEC in Monterey, CA in August 1994. The present paper describes the fabrication and testing of full-length prototypcial converters, both unfueled and fueled, and presents parametric results of electrically heated tests.

  17. Optical Recognition of Converted DNA Nucleotides for Single-Molecule DNA

    E-Print Network [OSTI]

    Optical Recognition of Converted DNA Nucleotides for Single-Molecule DNA Sequencing Using Nanopore among individual nucleotides (nt). The system must be capable of differentiating among the four bases

  18. Department of Mechanical & Nuclear Engineering Spring 2011 Converting Methane into Ethylene

    E-Print Network [OSTI]

    Demirel, Melik C.

    PENNSTATE Department of Mechanical & Nuclear Engineering Spring 2011 Converting Methane catalyst production labs, reactor testing lab, and testing equipment. Team Methane Fuzion was responsible. Temperature of the catalyst was closely monitored in order to prevent catalyst sintering. Testing

  19. The Utilization and Recovery of Energy from Blast Furnaces and Converters

    E-Print Network [OSTI]

    Hegemann, K. R.; Niess, T.; Baare, R. D.

    1979-01-01T23:59:59.000Z

    comprising a gas cleaning unit for dust removal and a turbine for converting the recoverable thermal energy into mechanical and electrical energy. The adjustable annular gap scrubber for separating fine dust also serves as an element for regulating the gas...

  20. Behavioral modeling and digital calibration of pipeline analog to digital converters

    E-Print Network [OSTI]

    Bilhan, Erkan

    2001-01-01T23:59:59.000Z

    This research focuses on digital calibration of pipeline analog to digital converters (ADCs) and also modeling of error sources and design parameters of pipeline ADCs. Modern applications such as communications systems require high resolution ADCs...

  1. A New Integrated Onboard Charger and Accessory Power Converter for Plug-in Electric Vehicles

    SciTech Connect (OSTI)

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

    2014-01-01T23:59:59.000Z

    In this paper, a new approach is presented for integrating the function of onboard battery charging into the traction drive system and accessory dc-dc converter of a plug-in electric vehicle (PEV). The idea is to utilize the segmented traction drive system of a PEV as the frond converter of the charging circuit and the transformer and high voltage converter of the 14 V accessory dc-dc converter to form a galvanically isolated onboard charger. Moreover, a control method is presented for suppressing the battery current ripple component of twice the grid frequency with the reduced dc bus capacitor in the segmented inverter. The resultant integrated charger has lower cost, weight, and volume than a standalone charger due to a substantially reduced component count. The proposed integrated charger topology was verified by modeling and experimental results on a 5.8 kW charger prototype.

  2. Fabrication of optical-mode converters for efficient fiber-to-silicon-waveguide couplers

    E-Print Network [OSTI]

    Barreto, Raúl E

    2007-01-01T23:59:59.000Z

    Optical-mode converters are needed to efficiently couple light from an optical fiber to a photonic circuit by matching and transforming the propagating modes. This work is based on a horizontally-tapered coupler, in which ...

  3. Methodology for determining feasibility and cost for converting dredged material to topsoil

    E-Print Network [OSTI]

    Graalum, Sara Jo Ann

    1997-01-01T23:59:59.000Z

    alternatives is to convert dredged material to manufactured soil (artificial topsoil). A limited number of studies have been conducted by the United States Army Corps of Engineers (USACE) Waterways Experiment Station in conjunction with local USACE Districts...

  4. System demonstration of an optically-sampled, wavelength-demultiplexed photonic analog-to-digital converter

    E-Print Network [OSTI]

    Peng, Michael Yung

    2011-01-01T23:59:59.000Z

    The performance of electronic analog-to-digital converters (ADCs) at high sampling rates is fundamentally limited by the timing jitter of electronic clocks. To circumvent this limitation, one method is to exploit the ...

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

    E-Print Network [OSTI]

    Inam, Wardah

    2013-01-01T23:59:59.000Z

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

  6. Design, Modeling, and Control of Three-Port Converters for Solar Power Applications.

    E-Print Network [OSTI]

    Reese, Justin M

    2007-01-01T23:59:59.000Z

    ??This paper describes the results of research into multi-port converter design and control, specifically a pair of three-port topologies based on the half-bridge and full-bridge… (more)

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

    SciTech Connect (OSTI)

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

    2008-01-01T23:59:59.000Z

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

  8. High-Power Converters and AC Drives IEEE PESC2005 Tutorial

    E-Print Network [OSTI]

    Wu, Bin

    @ee.ryerson.ca http://www.ee.ryerson.ca/~bwu/ 2 High-Power Converters and AC Drives 1. Introduction 2. Cascaded H-Bridge Drives · High-Power Semiconductor Devices High-Power Converters and AC Drives Bin Wu 4High · Multilevel Voltage Source Inverters N dC Cascaded H-bridge (CHB) Inverter dC Two Level Inverter dC Flying

  9. Identification of sorghum midge (Diptera: Cecidomyiidae): resistant lines among converted exotic sorghum

    E-Print Network [OSTI]

    Ali, Ali El Badawi

    1986-01-01T23:59:59.000Z

    1986) Ali E 1 Badawi Ali, B. S. , University of Khartoum, Khartoum, Sudan. Chairman of advisory cotmnittee: Dr. george L. Teetes. In an attempt to identify additional sorghum lines tant to so gh Sdg, t t ~ rtnt ~ ~so htd t (C q Stlott), field... converted exotic sorghum lines were obtained from Dr. Gary C. Peterson, Sorghum Breeder at the Texas A8 M University Agricultural Research and Extension Center at Lubbock. The converted exotic sorghum lines are identical to the tall, photo...

  10. An 8-bit current mode ripple folding analog to digital converter

    E-Print Network [OSTI]

    Dinc, Huseyin

    2012-06-07T23:59:59.000Z

    . 3. 4 Noise IV. RIPPLE FOLDING TECHNIQUE 1. Conceptual Description of Ripple Folding. . 2. Topologies to Implement Minimum-Maximum Detection. . . . . 2. 1 The Diode Bridge 2. 2 Bipolar Realization. . 2. 3 CMOS Realization 2. 4 Switched Current... single pole system. 23 Noise bandwidth. 24 Traditional folding A/D converter 25 (a) Conceptual ripple lolding A/D converter. . . . . . 21 23 23 . . . 30 . . . . . . 35 36 . . . . . 37 . . . 41 FIGURE Page 26 27 28 Diode bridge...

  11. Direct connection of series self-excited generators and HVDC converters

    SciTech Connect (OSTI)

    Arrillaga, J.; Macdonald, S.J.; Watson, N.R.; Watson, S. (Univ. Canterbury, Christchurch (New Zealand))

    1993-10-01T23:59:59.000Z

    An alternative and simpler solution is proposed for the direct connection of generators to HVdc converters. The generator exciter windings are connected in series with the output of the HVdc converter and take the place of the conventional smoothing reactor. Existing steady state and time domain simulation programs are modified to represent the behavior of the series direct connection scheme. It is shown that series excitation extends naturally the power transmission capability and permits fast fault clearances.

  12. Conducting a 3D Converted Shear Wave Project to Reduce Exploration Risk at Wister, CA

    Broader source: Energy.gov [DOE]

    DOE Geothermal Technologies Peer Review 2010 - Presentation. The primary objective of this project is to conduct a 3C 3D (converted shear wave) seismic survey to reduce exploration risk by characterizing fault and fracture geometrics at Wister, CA.The intent of the proposed program is to use a 3D seismic survey with converted shear waves combined with other available data to site and drill production wells at Wister, a blind geothermal resource.

  13. Stirling converters for space dynamic power concepts with 2 to 130 W{sub e} output

    SciTech Connect (OSTI)

    Ross, B.A. [Stirling Technology Co., Richland, WA (United States)

    1995-12-31T23:59:59.000Z

    Three innovative Stirling converter concepts are described. Two concepts are based on Pluto Fast Flyby (PFF) mission requirements, where two General Purpose Heat Source (GPHS) modules provide the thermal input. The first concept (PFF2) considers a power system with two opposed Stirling converters; the second concept (PFF4) considers four opposed Stirling converters. For both concepts the Stirling converters are designed to vary their power production capability to compensate for the failure of one Stirling converter. While the net thermal efficiency of PFF4 is a few percentage points lower than PFF2, the total Stirling converter mass of PFF4 is half that for PFF2. The third concept (ITTI) is designed to supply 2 watts of power for weather stations on the Martian surface. The predicted thermal performance of the ITTI is low compared to PFF2 and PFF4, yet the ITTI concept offers significant advantages compared to currently available power systems at the 2-watt power level. All three concepts are based on long-life technology demonstrated by an 11-watt output Stirling generator that as of March 1995 has accumulated over 15,000 operating hours without maintenance.

  14. Close-spaced thermionic converters with active spacing control and heat-pipe isothermal emitters

    SciTech Connect (OSTI)

    Fitzpatrick, G.O.; Koester, J.K.; Chang, J.; Britt, E.J.; McVey, J.B. [Space Power, Inc., San Jose, CA (United States)

    1996-12-31T23:59:59.000Z

    Thermionic converters with interelectrode gaps smaller than 10 microns are capable of substantial performance improvements over conventional ignited mode diodes. Previous devices which have demonstrated operation at such small gaps have done so at low power densities and emitter temperatures. Higher power operation requires overcoming two primary design issues: thermal distortion of the emitter due to temperature gradients and degradation of the in-gap spacers at higher emitter temperatures. This work describes two innovations for solution of these issues. The issue of thermal distortion was addressed by an isothermal emitter incorporating a heat-pipe into its structure. Such a heat-pipe emitter, with a single-crystal emitting surface, was fabricated and characterized. Finite-element computational modeling was used to analyze its distortion with an applied heat flux. The calculations suggested that thermal distortion would be significantly reduced as compared with a solid emitter. Ongoing work and preliminary experimental results are described for a system of active interelectrode gap control. In the present design an integral transducer determines the interelectrode gap of the converter. Initial designs for spacing actuators and their required cesium vapor seals are discussed. A novel hot-shell converter design incorporating active spacing control and low-temperature seals is presented. A converter incorporating the above features would be capable of near ideal-converter performance at high power densities. In addition, active spacing control can potentially completely eliminate short-circuit failures in thermionic converter systems.

  15. FINAL REPORT OF RESEARCH ON CuxS/ (Cd,Zn)S PHOTOVOLTAIC SOLAR ENERGY CONVERTERS 3/77 - 9/79

    E-Print Network [OSTI]

    Chin, B.L.

    2013-01-01T23:59:59.000Z

    S/(Cd,Zn)S PHOTOVOLTAIC SOLAR ENERGY CONVERTERS 3/77 - 9/79Research on Photovoltaic Solar Energy Converters CuxSI(Cd~

  16. Fabrication and Testing of Full-Length Single-Cell Externally Fueled Converters for Thermionic Reactors

    SciTech Connect (OSTI)

    Schock, Alfred

    1994-06-01T23:59:59.000Z

    The preceding paper described designs and analyses of thermionic reactors employing full-core-length single-cell converters with their heated emitters located on the outside of their internally cooled collectors, and it presented results of detailed parametric analyses which illustrate the benefits of this unconventional design. The present paper describes the fabrication and testing of full-length prototypical converters, both unfueled and fueled, and presents parametric results of electrically heated tests. The unfueled converter tests demonstrated the practicality of operating such long converters without shorting across a 0.3-mm interelectrode gap. They produced a measured peak output of 751 watts(e) from a single diode and a peak efficiency of 15.4%. The fueled converter tests measured the parametric performance of prototypic UO(subscript 2)-fueled converters designed for subsequent in-pile testing. They employed revolver-shaped tungsten elements with a central emitter hole surrounded by six fuel chambers. The full-length converters were heated by a water-cooled RF-induction coil inside an ion-pumped vacuum chamber. This required development of high-vacuum coaxial RF feedthroughs. In-pile test rules required multiple containment of the UO (subscript 2)-fuel, which complicated the fabrication of the test article and required successful development of techniques for welding tungsten and other refractory components. The test measured a peak power output of 530 watts(e) or 7.1 watts/cm (superscript 2) at an efficiency of 11.5%. There are three copies in the file. Cross-Reference a copy FSC-ESD-217-94-529 in the ESD files with a CID #8574.

  17. Local convertibility and the quantum simulation of edge states in many-body systems

    E-Print Network [OSTI]

    Fabio Franchini; Jian Cui; Luigi Amico; Heng Fan; Mile Gu; Vladimir E. Korepin; Leong Chuan Kwek; Vlatko Vedral

    2014-09-23T23:59:59.000Z

    In some many-body systems, certain ground state entanglement (Renyi) entropies increase even as the correlation length decreases. This entanglement non-monotonicity is a potential indicator of non-classicality. In this work we demonstrate that such a phenomenon, known as non-local convertibility, is due to the edge state (de)construction occurring in the system. To this end, we employ the example of the Ising chain, displaying an order-disorder quantum phase transitions. Employing both analytical and numerical methods, we compute entanglement entropies for various system bipartitions (A|B) and consider ground states with and without Majorana edge states. We find that the thermal ground states, enjoying the Hamiltonian symmetries, show non-local convertibility if either A or B are smaller than, or of the order of, the correlation length. In contrast, the ordered (symmetry breaking) ground state is always locally convertible. The edge states behavior explains all these results and could disclose a paradigm to understand local convertibility in other quantum phases of matter. The connection we establish between convertibility and non-local, quantum correlations provides a clear criterion of which features a universal quantum simulator should possess to outperform a classical machine.

  18. Evaluation of dichalcogenide compounds as possible sorption reservoirs for thermionic converters

    SciTech Connect (OSTI)

    Garner, S.D.; Horner-Richardson, K.D. (Thermacore, Inc., 780 Eden Road, Lancaster, Pennsylvania 17601 (United States)); Kim, K.Y. (WL/POOC, Wright-Patterson AFB, Ohio 45433-6563 (United States))

    1993-01-20T23:59:59.000Z

    Recently a metal matrix sorption reservoir (MMSR) was developed for use as a self-regulating internal cesium reservoir for thermionic converters. The MMSR contains powdered graphite in a sintered refractory metal matrix. This innovation opens up the possibility of using alternative intercalating compounds previously overlooked because they are typically only available in powder form. One such alternative is the general class of materials known as dichalcogenides of metals. The dichalcogenide compounds are of the form MX[sub 2] where M is a metal and X is either S, Se or Te. The dichalcogenides have the laminar structure required for intercalation and some have been shown to intercalate liquid metals under certain conditions. Selected refractory metal dichalcogenides have been evaluated as potential cesium sorption reservoirs in thermionic converters. Testing showed the majority of the dichalcogenides are not stable in the thermal environment of current Thermionic Fuel Element (TFE) designs. Of the seven compounds that can survive the high temperatures and vacuum, four are not compatible with the cesium vapor at converter temperatures. The three remaining dichalcogenide compounds suitable for use in thermionic converters did not intercalate cesium at typical converter operating conditions. The result of this work allow the continued effort towards developing an internal self-regulating cesium reservoir to be concentrated on graphite contained in MMSRs.

  19. Emitter tests in an open thermionic converter with vapor injection through the collector

    SciTech Connect (OSTI)

    Wriedt, S.; Moeller, K.; Holmlid, L.

    1986-12-15T23:59:59.000Z

    Mo and Pt emitters and a Ni collector with 400 laser-bored holes were used in an ''open'' thermionic converter. The alkali vapor was introduced into the converter through the array of holes in the collector from an adjacent alkali metal reservoir with separately controlled temperature. The overall results from the open thermionic converter are comparable to results from enclosed converters. The results found with a Cs plasma are encouraging, with barrier indices down to below 1.8 eV, at emitter temperatures around 1500 K in the case of a Mo emitter. The output power density was around 3.5 W cm/sup -2/. In the case of a Pt emitter, both Cs and K plasmas were used, with power densities up to 5.7 and 1.8 W cm/sup -2/, respectively close to 1800 K. The structure of the laser-bored collector may have contributed to these results, as well as the efficient removal of impurities in the ''open'' converter.

  20. Compact, Low-Profile Power Converters: Highly-Laminated, High-Saturation-Flux-Density, Magnetic Cores for On-Chip Inductors in Power Converter Applications

    SciTech Connect (OSTI)

    None

    2010-09-01T23:59:59.000Z

    ADEPT Project: Georgia Tech is creating compact, low-profile power adapters and power bricks using materials and tools adapted from other industries and from grid-scale power applications. Adapters and bricks convert electrical energy into useable power for many types of electronic devices, including laptop computers and mobile phones. These converters are often called wall warts because they are big, bulky, and sometimes cover up an adjacent wall socket that could be used to power another electronic device. The magnetic components traditionally used to make adapters and bricks have reached their limits; they can't be made any smaller without sacrificing performance. Georgia Tech is taking a cue from grid-scale power converters that use iron alloys as magnetic cores. These low-cost alloys can handle more power than other materials, but the iron must be stacked in insulated plates to maximize energy efficiency. In order to create compact, low-profile power adapters and bricks, these stacked iron plates must be extremely thin-only hundreds of nanometers in thickness, in fact. To make plates this thin, Georgia Tech is using manufacturing tools used in microelectromechanics and other small-scale industries.

  1. Design considerations for a thermophotovoltaic energy converter using heat pipe radiators

    SciTech Connect (OSTI)

    Ashcroft, J.; DePoy, D. [Lockheed Martin Corp., Schenectady, NY (United States)

    1997-06-01T23:59:59.000Z

    The purpose of this paper is to discuss concepts for using high temperature heat pipes to transport energy from a heat source to a thermophotovoltaic (TPV) converter. Within the converter, the condenser portion of each heat pipe acts as a photon radiator, providing a radiant flux to adjacent TPV cells, which in turn create electricity. Using heat pipes in this way could help to increase the power output and the power density of TPV systems. TPV systems with radiator temperatures in the range of 1,500 K are expected to produce as much as 3.6 W/cm{sup 3} of heat exchanger volume at an efficiency of 20% or greater. Four different arrangements of heat pipe-TPV energy converters are considered. Performance and sizing calculations for each of the concepts are presented. Finally, concerns with this concept and issues which remain to be considered are discussed.

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

    DOE Patents [OSTI]

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

    2012-12-11T23:59:59.000Z

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

  3. Experience in the installation of a microprocessor system for controlling converter units of the Vyborg substation

    SciTech Connect (OSTI)

    Gusakovskii, K. B.; Zmaznov, E. Yu.; Katantsev, S. V.; Mazurenko, A. K.; Mestergazi, V. A.; Prochan, G. G.; Funtikova, S. F. [High Voltage Direct Current Power Transmission Research Institute (NIIPT) (Russian Federation)

    2006-01-15T23:59:59.000Z

    The experience in the installation of modern digital systems for controlling converter units at the Vyborg converter substation on the basis of advanced microprocessor devices is considered. It is shown that debugging of a control and protection system on mathematical and physical models does not guarantee optimum control of actual converter devices. Examples of advancing the control and protection system are described, the necessity for which has become obvious in tests of actual equipment. Comparison of oscillograms of processes before optimization of the control system and after its optimization and adjustment shows that the digital control system makes it possible to improve substantially the algorithms of control and protection in the short term and without changing the hardware component.

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

    E-Print Network [OSTI]

    Sun, Jing

    2007-09-17T23:59:59.000Z

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

  5. IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 7, NO. 2, MAY 1992, PP. 673 683. POINT OF COLLAPSE METHODS APPLIED TO AC DC POWER SYSTEMS

    E-Print Network [OSTI]

    Cañizares, Claudio A.

    -node bifurcations in power systems including high voltage direct current HVDC transmission. Bus voltage pro les, become plausible when the dynamics for the HVDC system are included. Keywords: Voltage collapse, HVDC the subject of increasing study over the past few years 1 . Furthermore, the relative wide spread use of HVDC

  6. Evaluation of the effectiveness of shielding and filtering of HVDC converter stations

    SciTech Connect (OSTI)

    Dallaire, R.D.; Maruvada, P.S.

    1989-04-01T23:59:59.000Z

    The electromagnetic interference (EMI) generated by the periodic turn-on and turn-off of the valves is an important consideration in the design of HVDC converter stations. Remedial measures such as shielding the valve hall and filtering have been used in order to reduce the interference levels to acceptable values. The application of recently-developed Numerical Electromagnetic Code (NEC) to the problem of EMI from HVDC converter stations is investigated in this paper, with particular emphasis on evaluating the effectiveness of valve hall shielding and filtering.

  7. Risk assessment of converting salt caverns to natural gas storage. Final report, November 1994-July 1995

    SciTech Connect (OSTI)

    Harrison, M.R.; Ellis, P.F.

    1995-10-01T23:59:59.000Z

    The objective of this paper was an assessment of the risks of release of large quantities of natural gas from salt caverns converted from other uses to the storage of compressed natural gas (CNG). A total of 22 potential root causes for large releases of natural gas from converted salt converns were identified and ranked in terms of relative risk. While this project assessed the relative risks of major gas releases, the absolute risk was determined by implication to be extremely low, as indicated by the historical record.

  8. Chemical reactor for converting a first material into a second material

    DOE Patents [OSTI]

    Kong, Peter C

    2012-10-16T23:59:59.000Z

    A chemical reactor and method for converting a first material into a second material is disclosed and wherein the chemical reactor is provided with a feed stream of a first material which is to be converted into a second material; and wherein the first material is combusted in the chemical reactor to produce a combustion flame, and a resulting gas; and an electrical arc is provided which is passed through or superimposed upon the combustion flame and the resulting gas to facilitate the production of the second material.

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

    E-Print Network [OSTI]

    James Goodman; Anantha Chandrakasan; Abram P. Dancy

    1999-01-01T23:59:59.000Z

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

  10. Composite resonance: A circuit approach to the waveform distortion dynamics of an HVdc converter

    SciTech Connect (OSTI)

    Wood, A.R.; Arrillaga, J. [Univ. of Canterbury, Christchurch (New Zealand)] [Univ. of Canterbury, Christchurch (New Zealand)

    1995-10-01T23:59:59.000Z

    A frequency domain analysis is applied to a controlled HVdc converter interconnecting ac and dc networks. The converter is considered as a three port network, and described using transfer functions. Using ac and dc system frequency dependent impedances an equivalent electrical circuit is constructed. The concept of composite resonance is introduced to emphasize the interaction between the ac and dc systems, and a simplified damping factor derived to predict the dynamics of waveform distortion during transient recovery. The frequency domain analysis is verified by dynamic simulation.

  11. Chemical reactor and method for chemically converting a first material into a second material

    DOE Patents [OSTI]

    Kong, Peter C. (Idaho Falls, ID)

    2008-04-08T23:59:59.000Z

    A chemical reactor and method for converting a first material into a second material is disclosed and wherein the chemical reactor is provided with a feed stream of a first material which is to be converted into a second material; and wherein the first material is combusted in the chemical reactor to produce a combustion flame, and a resulting gas; and an electrical arc is provided which is passed through or superimposed upon the combustion flame and the resulting gas to facilitate the production of the second material.

  12. Electro-mechanical energy conversion system having a permanent magnet machine with stator, resonant transfer link and energy converter controls

    DOE Patents [OSTI]

    Skeist, S. Merrill; Baker, Richard H.

    2006-01-10T23:59:59.000Z

    An electro-mechanical energy conversion system coupled between an energy source and an energy load comprising an energy converter device including a permanent magnet induction machine coupled between the energy source and the energy load to convert the energy from the energy source and to transfer the converted energy to the energy load and an energy transfer multiplexer to control the flow of power or energy through the permanent magnetic induction machine.

  13. Institutional Arrangements for Effective Groundwater Management to Halt Land Subsidence

    E-Print Network [OSTI]

    Brah, W. L.; Jones, L. L.

    1978-01-01T23:59:59.000Z

    of groundwater use and development but political entities with adequate scope to deal with the problem were either unwilling or unable to engage in regional water management. Indeed, these political organizations and other institutions may have actually...

  14. Halting_Title_XVII_Nuclear_Loan_Guarantees.pdf

    Energy Savers [EERE]

    to eliminate the taxpayer as the primary claimant to fixed assets after a default, in order to make the loan guarantees more attractive to investors - such as the French and...

  15. Brush Busters: How to Put a Halt to Saltcedar

    E-Print Network [OSTI]

    McGinty, Allan; Hart, Charles R.

    2002-01-07T23:59:59.000Z

    absorption through the saltcedar bark. The recommended concentration of Remedy ? is 25 percent (see mixing table below). To mix, pour the required quantity of herbicide into a 1-gallon con- tainer, then bring to total volume with diesel fuel. Agitate... or number of basal stems per plant increases. ? Multiple-stemmed plants are more difficult to control with this method. ? After mixing herbicide with diesel fuel, shake or agitate the mixture vigorously. ? Controlling saltcedar is not a one-time job. You...

  16. Halting_Title_XVII_Nuclear_Loan_Guarantees.pdf

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarly Career Scientists'Montana.ProgramJulietip sheetK-4In 2013 many autoThis road map

  17. Eisenhower Halts Nuclear Weapons Testing | National Nuclear Security

    National Nuclear Security Administration (NNSA)

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

  18. Calculation of HVDC-converter harmonics in frequency domain with regard to asymmetries and comparison with time domain simulations

    SciTech Connect (OSTI)

    Rittiger, J. [Siemens AG, Erlangen (Germany)] [Siemens AG, Erlangen (Germany); Kulicke, B. [Technische Univ. Berlin (Germany)] [Technische Univ. Berlin (Germany)

    1995-10-01T23:59:59.000Z

    In order to study the effects of large HVDC converters to the feeding ac networks, it is of importance to explain and to calculate harmonic phenomena which are a result of converter operation. During commissioning of real HVDC converters it could be seen, that harmonics resulting from unsymmetries in the system voltages or from unsymmetries in converter operation led to significant difficulties concerning the system design. For this reason, not only the effects of characteristic but also the effects of noncharacteristic converter harmonics must be taken into account. The aim is to describe the steady state harmonic behavior of the converter. The harmonic spectra are not determined by time domain analysis but instead the solution is found by frequency domain calculations. This can result in reduced calculation time in comparison to conventional fourier analysis of the time functions. The converter is interpreted as an amplitude modulator with voltage and current converter functions which describe the coupling of the dc circuit and the ac network through the converter. To verify the theory, comparison of frequency domain with time domain calculations were carried out.

  19. WindTurbineGenerator Introduction of the Renewable Micro-Grid Test-Bed

    E-Print Network [OSTI]

    Johnson, Eric E.

    Simulator Wind Turbine: PMSM, 3kW, 8.3A Wind Generator: PMSM, 3kW, 8.3A 3 AC/DC Converter & DC/AC Inverter Wind Turbine: Torque or Speed Control Wind Generator: PQ Control Cubicle #4: Energy Storage Generator #1 3kW, 8.3A Wind Turbine #1 3kW, 8.3A Wind Turbine #2 3kW Wind Generator #2 3kW RS232

  20. LABORATORY OBSERVATIONS AND NUMERICAL MODELING OF THE EFFECTS OF AN ARRAY OF WAVE ENERGY CONVERTERS

    E-Print Network [OSTI]

    Haller, Merrick

    1 LABORATORY OBSERVATIONS AND NUMERICAL MODELING OF THE EFFECTS OF AN ARRAY OF WAVE ENERGY of wave energy converters (WECs) on water waves through the analysis of extensive laboratory experiments absorption is a reasonable predictor of the effect of WECs on the far field. Keywords: wave- energy; spectral

  1. A 3-phase AC to AC matrix converter using the Venturini method

    E-Print Network [OSTI]

    Dabbousi, Rami M. Osama

    2002-01-01T23:59:59.000Z

    to be used for motor drives. Consequently, there is a potential reduction in drive manufacturing cost, as well as improvement in the power-per-weight and power-per-volume ratios. Furthermore, the converter design makes it capable of bi-directional power...

  2. Video Article Continuously-Stirred Anaerobic Digester to Convert Organic Wastes into

    E-Print Network [OSTI]

    Angenent, Lars T.

    Video Article Continuously-Stirred Anaerobic Digester to Convert Organic Wastes into Biogas: System@cornell.edu URL: http://www.jove.com/video/3978/ DOI: 10.3791/3978 Keywords: Anaerobic Digestion, Bioenergy, Biogas, Methane, Organic Waste, Methanogenesis, Energy Crops, Date Published: // Citation: Usack

  3. A short and simple explanation of how oil is converted into gasoline and then brought to

    E-Print Network [OSTI]

    it is not usable. It must first be sent to a refinery where it is converted into many dif- ferent products that we or thicker the oil, the more work the refinery must do to distill it into a useful form. The second, the most economical way to transport crude oil from the well to the refinery is through pipelines. While

  4. A Hybrid Energy System Using Cascaded H-bridge Converter , Zhong Du2

    E-Print Network [OSTI]

    Tolbert, Leon M.

    schemes were developed to extract maximum wind power and charge/discharge the battery with fast dynamics proposes a hybrid energy system to integrate the variable-speed wind turbine, fuel cell, and battery using a cascaded H-bridge converter. One of the advantages of this topology is that it still can obtain

  5. Integration of planar transformer and/or planar inductor with power switches in power converter

    DOE Patents [OSTI]

    Chen, Kanghua (Canton, MI); Ahmed, Sayeed (Canton, MI); Zhu, Lizhi (Canton, MI)

    2007-10-30T23:59:59.000Z

    A power converter integrates at least one planar transformer comprising a multi-layer transformer substrate and/or at least one planar inductor comprising a multi-layer inductor substrate with a number of power semiconductor switches physically and thermally coupled to a heat sink via one or more multi-layer switch substrates.

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

    E-Print Network [OSTI]

    Harfman Todorovic, Maja

    2006-04-12T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

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

  8. An Improved MPPT Interleaved Boost Converter for Solar Electric Vehicle Application

    E-Print Network [OSTI]

    Boyer, Edmond

    during transient and instantaneous peak power demands of an electric vehicle (EV) and to recover energyAn Improved MPPT Interleaved Boost Converter for Solar Electric Vehicle Application F. Khoucha, A and lower device stress than conventional designs, for solar electric vehicle (SEV) applications

  9. Integrated Power Adapter: Isolated Converter with Integrated Passives and Low Material Stress

    SciTech Connect (OSTI)

    None

    2010-09-01T23:59:59.000Z

    ADEPT Project: CPES at Virginia Tech is developing an extremely efficient power converter that could be used in power adapters for small, lightweight laptops and other types of mobile electronic devices. Power adapters convert electrical energy into useable power for an electronic device, and they currently waste a lot of energy when they are plugged into an outlet to power up. CPES at Virginia Tech is integrating high-density capacitors, new magnetic materials, high-frequency integrated circuits, and a constant-flux transformer to create its efficient power converter. The high-density capacitors enable the power adapter to store more energy. The new magnetic materials also increase energy storage, and they can be precisely dispensed using a low-cost ink-jet printer which keeps costs down. The high-frequency integrated circuits can handle more power, and they can handle it more efficiently. And, the constant-flux transformer processes a consistent flow of electrical current, which makes the converter more efficient.

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

    E-Print Network [OSTI]

    Paderborn, Universität

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

  11. PM brushless DC motor drive with a new power converter topology

    SciTech Connect (OSTI)

    Krishnan, R.; Lee, S. [Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States)

    1995-12-31T23:59:59.000Z

    With the growing potential for widespread use of permanent magnet brushless dc motor drives (hereafter referred to as PMBDC drives) in many low-cost applications such as in hvac, refrigerators, and freezers in houses and small velocity servos in process industries, it has become important to minimize the cost. One obvious place for cost reduction is in the cost of the inverter and its associated controller. With that perspective, a novel application of the converter topology for the PMBDC known as C-dump in the switched reluctance motor drives is proposed in this paper. The advantages and disadvantages of this topology vis-a-vis the conventional 3 phase H-bridge converter, are highlighted from the points of view of economy in switches, volt ampere rating, associated controller cost, and packaging. Design considerations for the PMBDC motor are derived for use with the proposed converter topology. The operational and design characteristics of this converter driven PMBDC drive are derived for four quadrant performance. Guidelines for the design of the proposed performance. Guidelines for the design of the proposed topology are derived and presented in the paper. Experimental results from a laboratory prototype are presented to validate the feasibility of the proposed PMBDC drive system.

  12. HEXHOOP: MODULAR TEMPLATES FOR CONVERTING A HEX-DOMINANT MESH TO AN ALL-HEX MESH

    E-Print Network [OSTI]

    Shimada, Kenji

    . Such conversion templates make all-hex meshing possible for a complicated geometry for which the existing direct conversion template, called HEXHOOP, that fully automates a conversion from a hex-dominant mesh to an all templates successfully convert a hex-dominant mesh to an all-hex mesh. Keywords: mesh conversion, template

  13. High-efficient solar power systems based on thermionic converter with small gap

    SciTech Connect (OSTI)

    Nikolaev, Y.V.; Eryomin, S.A.; Kalmykov, S.S.; Karpechenko, Y.D.; Kucherov, R.Y.; Lapochkin, N.V. [Research Institute of Scientific Industrial Association ``Lutch``, 142100, Podolsk, Moscow Region (Russian Federation)

    1996-03-01T23:59:59.000Z

    Various configurations of power systems based on thermionic converter with small interelectrode gap have been considered. The results of studies of systems energy characteristics are presented. The high efficiency and perspectivety of such systems for different applications have been shown. {copyright} {ital 1996 American Institute of Physics.}

  14. Fast neutron thermionic-converters for high-power space nuclear power systems. [Na; K

    SciTech Connect (OSTI)

    Pupko, V.Y.; Vizgalov, A.V.; Raskach, F.P.; Shestjorkin, A.G.; Almambetov, A.K. (Obninsk, Kaluga region, USSR (SU)); Bystrov, P.I.; Yuditsky, V.D.; Sobolev, Y.A.; Sinyavsky, V.V.; Bakanov, Y.A.; Lipovy, N.M. (SIA Energiya'', Kaliningrad, Moscow (USSR)); Gryaznov, G.M.; Serbin, V.I.; Trykhanov, Y.L. (SIA Krasnaya Zvezda'', Moscow (USSR))

    1991-01-05T23:59:59.000Z

    The results of tests with a thermionic reactor-converter utilizing fast neutrons and a high temperature cooling system are described. The reactor can be useful for a wide range of applications with a specific mass of about 20 kg/kW and power level of 2500 kW. (AIP)

  15. A Stochastic Time-to-Digital Converter for Digital Phase-Locked Loops submitted to

    E-Print Network [OSTI]

    Moon, Un-Ku

    A Stochastic Time-to-Digital Converter for Digital Phase-Locked Loops by Kerem Ok A THESIS. Thanks to Tufan for always being ready to go lifting or to Platinum (Thanks Dave) or Senor Sam's with me.1.2 Synthesis Using Digital PLLs........................................................ 8 3. STOCHASTIC TIME

  16. Converted wave imaging in anisotropic media using sea-floor seismic data 

    E-Print Network [OSTI]

    Mancini, Fabio

    velocity ratio is derived conventionally by event matching in the P-wave and converted wave stacks. I present an attempt to use well-log derived velocity ratios to avoid this interpretative step. The velocity ratio derived from 4C seismic data is about 30...

  17. Converting PETAL, the 25m solar collector, into an astronomical research facility

    E-Print Network [OSTI]

    Ribak, Erez

    1 Converting PETAL, the 25m solar collector, into an astronomical research facility Erez N. Ribak and Astronomy, Tel Aviv University, Israel ABSTRACT We propose to modify the solar collector PETAL (Photon collector, which has a relatively poor imaging quality. The conversion can be done by either of two

  18. Compact EMC model of power electronics converter for conducted EMC studies in embedded networks

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Page 1/7 Compact EMC model of power electronics converter for conducted EMC studies in embedded - University of Lyon Abstract This paper presents a "black box" model for EMC prediction of power electronics is the forecast of ElectroMagnetic Compatibility behaviour at system level in embedded networks. Keywords: EMC

  19. An Assessment of Converter Modelling Needs for Offshore Wind Power Plants Connected via VSC-

    E-Print Network [OSTI]

    Bak, Claus Leth

    An Assessment of Converter Modelling Needs for Offshore Wind Power Plants Connected via VSC- HVDC high voltage direct current (HVDC) transmission is technically superior to other technologies of such complex devices. This paper presents an investigation of the modelling requirements of the MMCC HVDC

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

    E-Print Network [OSTI]

    Denniston, Nicholas Aaron

    2011-08-08T23:59:59.000Z

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

  1. Novel Cell based on Reduced Single-phase Active Front End for Multicell Converters.

    E-Print Network [OSTI]

    Duffy, Ken

    V] and power of several Megawatts. Among different topologies [1], the cascaded Multicell [2] inverter has converters are a very interesting al- ternative for medium and high power drives. One of the more flexible topologies of this type is the Multicell con- verter. This paper presents a new regenerative cell suitable

  2. A New Approach to the Elimination of Harmonics in a Multilevel Converter

    E-Print Network [OSTI]

    Tolbert, Leon M.

    , the approach here produces all possible solutions. 1 Introduction A multilevel inverter is a power electronicA New Approach to the Elimination of Harmonics in a Multilevel Converter John N. Chiasson, Leon M that by reformulating the problem in terms of power sums, the degrees of the polynomial equations that must be solved

  3. Design Method and Automation of Comparator Generation for Flash A/D Converter

    E-Print Network [OSTI]

    Choi, Kyusun

    processing system demands high- speed operation and less power consumption. A new flash ADC design. The threshold inverter quantization (TIQ) based A/D converters require 2n , 1 comparators, each one different, 3] rate. It consumes more power and occupies larger chip area in comparison to the other types

  4. A New Approach to Solving the Harmonic Elimination Equations for a Multilevel Converter

    E-Print Network [OSTI]

    Tolbert, Leon M.

    possible solutions. I. Introduction A multilevel inverter is a power electronic device built to synthesizeA New Approach to Solving the Harmonic Elimination Equations for a Multilevel Converter John N voltages, and if this energy is to be fed to into an ac power grid, a power electronic interface

  5. A Universal Level Converter Towards the Realization of Energy Efficient Implantable Drug Delivery

    E-Print Network [OSTI]

    Mohanty, Saraju P.

    of the system which will then require a heat transfer mech- anism, affecting the portion of the body whereA Universal Level Converter Towards the Realization of Energy Efficient Implantable Drug Delivery and can block an input signal. We have prototyped a ULC using 32nm high-/metal-gate nano-CMOS technology

  6. Time-Optimal Control in Dc-Dc Converters: A Maximum Principle Perspective

    E-Print Network [OSTI]

    Liberzon, Daniel

    the development of advanced nonlinear control methods [1], [2]. For instance, time-optimal and proximate time] establishes single-switch time-optimal control of buck converters and inverters; however, this has not been function to be minimized is of the form J(u) = tf t0 L(x(t), u(t))dt, (2) where tf denotes the terminal

  7. A time-based energy-efficient analog-to-digital converter

    E-Print Network [OSTI]

    Yang, Heemin Yi, 1976-

    2006-01-01T23:59:59.000Z

    Dual-slope converters use time to perform analog-to-digital conversion but require 2N+1 clock cycles to achieve N bits of precision. We describe a novel algorithm that also uses time to perform analog-to-digital conversion ...

  8. High Efficiency Interleaved Power Electronics Converter for wide operating power range

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    at there nominal power. The converters are using an output filtering structure with magnetical coupling to its nominal power). Many applications, like solar power plant or VSD systems with variable torque%, will see his efficiency decreasing to 85 % if it works at 50% of his nominal power. If the output power

  9. Bacteria can help convert waste to power IANS 7 September 2009, 02:59pm IST

    E-Print Network [OSTI]

    Lovley, Derek

    that generate power could be used in microbial fuel cells to convert waste into electricity, according counterparts with a smooth surface. The researchers isolated a strain of Geobacter sulfurreducens which-film on the anode surface, which conducted electricity. The researchers found large quantities of pilin, a protein

  10. Stresa, Italy, 25-27 April 2007 STEP-UP CONVERTER FOR ELECTROMAGNETIC VIBRATIONAL ENERGY

    E-Print Network [OSTI]

    Boyer, Edmond

    micro-machined vibration based power generator with diode based voltage multiplier (VM) circuits which the piezoceramic composite beam coupled with a flyback converter circuit and also derived the equivalent circuits and the EM vibration harvesting device. The measured and calculated results of the VM circuits for the

  11. TAS-2013-0043 1 Abstract--Fuel cells are electrochemical energy converters

    E-Print Network [OSTI]

    Boyer, Edmond

    of the perfectly direct current relies upon a fuel cell fed by hydrogen. The main advantages to be taken from fuelTAS-2013-0043 1 Abstract--Fuel cells are electrochemical energy converters which allow generation. Fuel cells are then by essence low voltage sources , so that for most practical applications

  12. Predictive Power Control of Doubly-Fed Induction Generator for Wave Energy Converters

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    energy resource plan. An extremely abundant and promising source of energy exists in oceans of the following categories: wave energy, marine and tidal current energy, ocean thermal energy, energy fromPredictive Power Control of Doubly-Fed Induction Generator for Wave Energy Converters M.S. Lagoun1

  13. A Predictive power control of Doubly Fed Induction Generator for Wave Energy Converter

    E-Print Network [OSTI]

    Brest, Université de

    's excessive energy demand. An extremely abundant and promising source of energy exists in oceans. Currently be included in one of the following categories: wave energy, marine and tidal current energy, ocean thermalA Predictive power control of Doubly Fed Induction Generator for Wave Energy Converter in Irregular

  14. High Efficiency Thermionics (HET-IV) and Converter Advancement (CAP) programs. Final reports

    SciTech Connect (OSTI)

    Geller, C.B.; Murray, C.S.; Riley, D.R. [Bettis Atomic Power Lab., West Mifflin, PA (United States)] [Bettis Atomic Power Lab., West Mifflin, PA (United States); Desplat, J.L.; Hansen, L.K.; Hatch, G.L.; McVey, J.B.; Rasor, N.S. [Rasor Associates, Inc., Sunnyvale, CA (United States)] [Rasor Associates, Inc., Sunnyvale, CA (United States)

    1996-04-01T23:59:59.000Z

    This report contains the final report of the High Efficiency Thermionics (HET-IV) Program, Attachment A, performed at Rasor Associates, Inc. (RAI); and the final report of the Converter Advancement Program (CAP), performed at the Bettis Atomic Power Laboratory, Attachment B. The phenomenology of cesium-oxygen thermionic converters was elucidated in these programs, and the factors that had prevented the achievement of stable, enhanced cesium-oxygen converter performance for the previous thirty years were identified. Based on these discoveries, cesium-oxygen vapor sources were developed that achieved stable performance with factor-of-two improvements in power density and thermal efficiency, relative to conventional, cesium-only ignited mode thermionic converters. Key achievements of the HET-IV/CAP programs are as follows: a new technique for measuring minute traces of oxygen in cesium atmospheres; the determination of the proper range of oxygen partial pressures for optimum converter performance--10{sup {minus}7} to 10{sup {minus}9} torr; the discovery, and analysis of the cesium-oxygen liquid migration and compositional segregation phenomena; the successful use of capillary forces to contain the migration phenomenon; the use of differential heating to control compositional segregation, and induce vapor circulation; the development of mechanically and chemically stable, porous reservoir structures; the development of precise, in situ oxygen charging methods; stable improvements in emitter performance, up to effective emitter bare work functions of 5.4 eV; stable improvements in barrier index, to value below 1.8 Volts; the development of detailed microscopic models for cesium-oxygen reservoir dynamics and collector work function behavior; and the discovery of new relationships between electrode geometry and Schock Instability.

  15. convert program

    National Nuclear Security Administration (NNSA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartmentNationalRestart of the Review of theOFFICE OF CIVILAMENDMENT OF0/%2A1/%2A

  16. THE FORCE OF A TSUNAMI ON A WAVE ENERGY CONVERTER LAURA O'BRIEN, PAUL CHRISTODOULIDES, EMILIANO RENZI, DENYS DUTYKH,

    E-Print Network [OSTI]

    THE FORCE OF A TSUNAMI ON A WAVE ENERGY CONVERTER LAURA O'BRIEN, PAUL CHRISTODOULIDES, EMILIANO in the open ocean but as the wave approaches the shore its energy is com­ pressed creating large destructive waves. The question posed here is whether a nearshore wave energy converter (WEC) could withstand

  17. THE FORCE OF A TSUNAMI ON A WAVE ENERGY CONVERTER LAURA O'BRIEN, PAUL CHRISTODOULIDES, EMILIANO RENZI, DENYS DUTYKH,

    E-Print Network [OSTI]

    Boyer, Edmond

    THE FORCE OF A TSUNAMI ON A WAVE ENERGY CONVERTER LAURA O'BRIEN, PAUL CHRISTODOULIDES, EMILIANO in the open ocean but as the wave approaches the shore its energy is com- pressed creating large destructive waves. The question posed here is whether a nearshore wave energy converter (WEC) could withstand

  18. http://digitalcommons.unl.edu/elecengtheses/6 DC/DC Converter for a Small Scale Wind Hydrogen System By

    E-Print Network [OSTI]

    Joel M. Jacobs; Joel M. Jacobs; Joel Michael Jacobs; Adviser Jerry; L. Hudgins

    An electronic converter is designed for an isolated renewable energy system. In this system, energy produced by a small wind turbine is used to extract hydrogen from water. Unique aspects of this application that affect the performance of the converter will be defined. Design considerations of the individual components will be discussed. Calculations on performance and validation of those calculations are also presented.

  19. Author's personal copy Pyroelectric energy converter using co-polymer P(VDF-TrFE) and Olsen cycle

    E-Print Network [OSTI]

    Pilon, Laurent

    of waste heat [1]. To date, the effort has focused on thermoelectric generators based on the Seebeck effect for waste heat energy harvesting Hiep Nguyen, Ashcon Navid, Laurent Pilon* University of California, Los, building, and testing a pyroelectric energy converter to directly convert waste heat into electricity

  20. LM231A/LM231/LM331A/LM331 Precision Voltage-to-Frequency Converters

    E-Print Network [OSTI]

    Lanterman, Aaron

    LM231A/LM231/LM331A/LM331 Precision Voltage-to-Frequency Converters General Description The LM231/LM331 family of voltage-to-frequency converters are ideally suited for use in simple low, the LM231A/LM331A attain a new high level of accuracy versus temperature which could only be at- tained

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

    E-Print Network [OSTI]

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

  2. A three-level buck converter to regulate a high-voltage DC-to-AC inverter

    E-Print Network [OSTI]

    Schrock, Kenneth C

    2008-01-01T23:59:59.000Z

    A three-level buck converter is designed and analyzed, and shown to be suitable as a high-voltage down converter as a pre-regulation stage for a 600 watt DC-to-AC power inverter. Topology selection for the inverter is ...

  3. All-optical 4-bit Gray code to binary coded decimal converter Young Jin Jung*a

    E-Print Network [OSTI]

    Park, Namkyoo

    and Technology / Seoul, Korea, 130-791 ABSTRACT All-optical 4-bit Gray code to binary coded decimal (BCD-level simplification method and Karnaugh map method to design Gray code to BCD converter, general design concept was also founded in this research not only for the Gray code to BCD converter but also for any general

  4. New Power Electronics Converter Interfacing a Hybrid Dc/Ac Microgrid M. Alibeik, E. C. dos Santos Jr.

    E-Print Network [OSTI]

    Zhou, Yaoqi

    New Power Electronics Converter Interfacing a Hybrid Dc/Ac Microgrid M. Alibeik, E. C. dos Santos microgrid is that it has higher efficiency and lesser power conversion. In this work is proposed a new integrated power electronics converter able to connect a Distributed Generation (DG) unit with a hybrid dc

  5. Maximal energy that can be converted by a dielectric elastomer generator Soo Jin Adrian Koh,1,2

    E-Print Network [OSTI]

    Suo, Zhigang

    generators have been designed to harvest energy from walking,5,6 ocean waves,7 wind, and combustion.8Maximal energy that can be converted by a dielectric elastomer generator Soo Jin Adrian Koh,1 2009 Mechanical energy can be converted to electrical energy by using a dielectric elastomer generator

  6. A Transformer-less Partial Power Boost Converter for PV Applications Using a Three-Level Switching Cell

    SciTech Connect (OSTI)

    Mohammed Agamy; Maja Harfman-Todorovic; Ahmed Elasser; Somasundaram Essakiappan

    2013-03-01T23:59:59.000Z

    Photovoltaic architectures with distributed power electronics provide many advantages in terms of energy yield as well as system level optimization. As the power level of the solar farm increases it becomes more beneficial to increase the dc collection network voltage, which requires the use of power devices with higher voltage ratings, and thus making the design of efficient, low cost, distributed power converters more challenging. In this paper a simple partial power converter topology is proposed. The topology is implemented using a three-level switching cell, which allows the use of semiconductor devices with lower voltage rating; thus improving design and performance and reducing converter cost. This makes the converters suitable for use for medium to high power applications where dc-link voltages of 600V~1kV may be needed without the need for high voltage devices. Converter operation and experimental results are presented for two partial power circuit variants using three-level switching cells.

  7. Boost Converters for Gas Electric and Fuel Cell Hybrid Electric Vehicles

    SciTech Connect (OSTI)

    McKeever, JW

    2005-06-16T23:59:59.000Z

    Hybrid electric vehicles (HEVs) are driven by at least two prime energy sources, such as an internal combustion engine (ICE) and propulsion battery. For a series HEV configuration, the ICE drives only a generator, which maintains the state-of-charge (SOC) of propulsion and accessory batteries and drives the electric traction motor. For a parallel HEV configuration, the ICE is mechanically connected to directly drive the wheels as well as the generator, which likewise maintains the SOC of propulsion and accessory batteries and drives the electric traction motor. Today the prime energy source is an ICE; tomorrow it will very likely be a fuel cell (FC). Use of the FC eliminates a direct drive capability accentuating the importance of the battery charge and discharge systems. In both systems, the electric traction motor may use the voltage directly from the batteries or from a boost converter that raises the voltage. If low battery voltage is used directly, some special control circuitry, such as dual mode inverter control (DMIC) which adds a small cost, is necessary to drive the electric motor above base speed. If high voltage is chosen for more efficient motor operation or for high speed operation, the propulsion battery voltage must be raised, which would require some type of two-quadrant bidirectional chopper with an additional cost. Two common direct current (dc)-to-dc converters are: (1) the transformer-based boost or buck converter, which inverts a dc voltage, feeds the resulting alternating current (ac) into a transformer to raise or lower the voltage, and rectifies it to complete the conversion; and (2) the inductor-based switch mode boost or buck converter [1]. The switch-mode boost and buck features are discussed in this report as they operate in a bi-directional chopper. A benefit of the transformer-based boost converter is that it isolates the high voltage from the low voltage. Usually the transformer is large, further increasing the cost. A useful feature of the switch mode boost converter is its simplicity. Its inductor must handle the entire current, which is responsible for its main cost. The new Z-source inverter technology [2,3] boosts voltage directly by actively using the zero state time to boost the voltage. In the traditional pulse width modulated (PWM) inverter, this time is used only to control the average voltage by disconnecting the supply voltage from the motor. The purpose of this study is to examine the Z-source's potential for reducing the cost and improving the reliability of HEVs.

  8. Design of a High Power Continuous Source of Broadband Down-Converted Light

    E-Print Network [OSTI]

    Avi Pe'er; Yaron Silberberg; Barak Dayan; Asher A. Friesem

    2006-08-29T23:59:59.000Z

    We present the design and experimental proof of principle of a low threshold optical parametric oscillator (OPO) that continuously oscillates over a large bandwidth allowed by phase matching. The large oscillation bandwidth is achieved with a selective two-photon loss that suppresses the inherent mode competition, which tends to narrow the bandwidth in conventional OPOs. Our design performs pairwise mode-locking of many frequency pairs, in direct equivalence to passive mode-locking of ultrashort pulsed lasers. The ability to obtain high powers of continuous \\textit{and} broadband down-converted light enables the optimal exploitation of the correlations within the down-converted spectrum, thereby strongly affecting two-photon interactions even at classically high power levels, and opening new venues for applications such as two-photon spectroscopy and microscopy and optical spread spectrum communication.

  9. Total compensation of line-side switching harmonics in converter-fed ac locomotives

    SciTech Connect (OSTI)

    Krah, J.O.; Holtz, J. [Univ. of Wuppertal (Germany)] [Univ. of Wuppertal (Germany)

    1995-11-01T23:59:59.000Z

    PWM controlled line-side converters of modern ac traction locomotives inject harmonic currents into the feeding overhead line. This causes problems of electromagnetic interference. Passive or active filters are usually provided for a partial reduction of the line harmonics. A novel and superior approach employs a switched electronic compensator. It generates an exact replica of the harmonic current, feeding it to the high-voltage transformer to produce a harmonic counter MMF. The transformer main flux is then forced to be sinusoidal, and so is the induced voltage in the primary. The line current, being low-pass filtered by the transformer leakage inductance, assumes a pure sinusoidal waveform. The compensator operates in the low switching frequency range of the main power converters. Its installed power is only 1% of the traction power. Operation, control, and design considerations are described. Results from laboratory tests at full power level are presented.

  10. Propulsion system for a motor vehicle using a bidirectional energy converter

    DOE Patents [OSTI]

    Tamor, Michael Alan (Toledo, OH); Gale, Allan Roy (Livonia, MI)

    1999-01-01T23:59:59.000Z

    A motor vehicle propulsion system includes an electrical energy source and a traction motor coupled to receive electrical energy from the electrical energy source. The system also has a first bus provided electrical energy by the electrical energy source and a second bus of relatively lower voltage than the first bus. In addition, the system includes an electrically-driven source of reaction gas for the electrical energy source, the source of reaction gas coupled to receive electrical energy from the first bus. Also, the system has an electrical storage device coupled to the second bus for storing electrical energy at the lower voltage. The system also includes a bidirectional energy converter coupled to convert electrical energy from the first bus to the second bus and from the second bus to the first bus.

  11. Efficient Power Converters for PV Arrays : Scalable Submodule Power Conversion for Utility-Scale Photovoltaics

    SciTech Connect (OSTI)

    None

    2012-02-23T23:59:59.000Z

    Solar ADEPT Project: SolarBridge is developing a new power conversion technique to improve the energy output of PV power plants. This new technique is specifically aimed at large plants where many solar panels are connected together. SolarBridge is correcting for the inefficiencies that occur when two solar panels that encounter different amounts of sun are connected together. In most conventional PV system, the weakest panel limits the energy production of the entire system. That’s because all of the energy collected by the PV system feeds into a single collection point where a central inverter then converts it into useable energy for the grid. SolarBridge has found a more efficient and cost-effective way to convert solar energy, correcting these power differences before they reach the grid.

  12. Recombination Lifetime of InxGa1-xAs Alloys Used in Thermophotovoltaic Converters

    SciTech Connect (OSTI)

    Ahrenkiel, R. K.; Ellingson, R.; Johnston, S.; Webb, J.; Carapella, J.; Wanlass, M.

    1999-02-16T23:59:59.000Z

    The family of ternary compounds of composition InxGa1-xAs are of considerable interest for thermophotovoltaic energy converters. The recombination lifetimes of the various compositions are critical to the successful application of these materials as efficient converters. Here we will describe experimental results on the composition. In0.53Ga0.47 that is lattice-matched to InP. We will also describe lifetime results on the compositions In0.68Ga0.32As, with bandgap of 0.60 eV to compositions In0.78Ga0.22As with a bandgap of 0.50 eV. Double heterostructure confinement devices have been made over a range of both n- and p-type doping. These results are preliminary, but the goal is to obtain the radiative and Auger recombination coefficients for the alloys in this composition range.

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

    E-Print Network [OSTI]

    Aguglia, D

    2014-01-01T23:59:59.000Z

    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.

  14. Solid oxygen as converter for the production of ultra-cold neutrons

    E-Print Network [OSTI]

    A. Frei; F. Böhle; R. Bozhanova; E. Gutsmiedl; T. Huber; J. Klenke; S. Paul; S. Wlokka

    2010-06-15T23:59:59.000Z

    We have investigated solid oxygen as a converter material for the production of ultra-cold neutrons. In a first series of experiments the crystal preparation was examined. An optically semi-transparent solid $\\alpha$-oxygen crystal has been prepared. In a second series of experiments such a crystal prepared indentically as in the first series of experiments has been exposed to the cold neutron flux of the MEPHISTO beam line of the FRM II. Ultra-cold neutrons produced inside the oxygen crystal have been extracted and the count rates have been measured at different converter temperatures. The results of these measurements give a clear signal of the superthermal UCN production mechanism in $\\alpha$-oxygen. The mean free loss length of UCN inside the crystal at a temperature of 5\\,K was determined to be in the order of $20\\,\\mathrm{cm}$.

  15. Calculation of HVDC converter noncharacteristic harmonics using digital time-domain simulation method

    SciTech Connect (OSTI)

    Sarshar, A. [Trench Electric, Scarborough, Ontario (Canada)] [Trench Electric, Scarborough, Ontario (Canada); Iravani, M.R.; Li, J. [Univ. of Toronto, Ontario (Canada). Dept. of Electrical and Computer Engineering] [Univ. of Toronto, Ontario (Canada). Dept. of Electrical and Computer Engineering

    1996-01-01T23:59:59.000Z

    In this paper, noncharacteristic harmonics of an HVdc converter station are calculated based on the use of digital time-domain simulation methods. An enhanced version of the Electromagnetic Transients Program (EMTP) is used for the studies. The noncharacteristic harmonics of interest are (1) the dc side triplen harmonics, and (2) the ac side second harmonic. Impacts of loading conditions, neutral filter, and converter firing angle on the dc side triplen harmonics are discussed. Effects of ac side network parameters, static VAR compensator (SVC), transformer half-cycle saturation, and Geomagnetically Induced Current (GIC) on the ac side second harmonic instability are also presented. This paper concludes that the digital time-domain simulation method provides significant flexibility for accurate prediction of (1) generation mechanism, and (2) adverse impacts of HVdc noncharacteristic harmonics.

  16. High-efficiency, monolithic, multi-bandgap, tandem, photovoltaic energy converters

    DOE Patents [OSTI]

    Wanlass, Mark W

    2014-05-27T23:59:59.000Z

    A monolithic, multi-bandgap, tandem solar photovoltaic converter has at least one, and preferably at least two, subcells grown lattice-matched on a substrate with a bandgap in medium to high energy portions of the solar spectrum and at least one subcell grown lattice-mismatched to the substrate with a bandgap in the low energy portion of the solar spectrum, for example, about 1 eV.

  17. Wavelength tunable polarization mode converter utilizing static strain effects in lithium niobate

    E-Print Network [OSTI]

    Kwon, Ojin

    2012-06-07T23:59:59.000Z

    , " Electron. Lett. , vol. 35, no. 3, pp. 219-220, 1999. [14] O. Eknoyan, C. H. Bulmer, H. F. Taylor, W. K. Burns, A. S. Greenblatt, L. A. Beach and R. R. Neurgaonkar, "Vapor diffused optical waveguides in strontium barium niobate (SBN:60), " Appl. Phys...WAVELENGTH TUNABLE POLARIZATION MODE CONVERTER UTILIZING STATIC STRAIN EFFECTS IN LITHIUM NIOBATE A Thesis by OJIN KWON Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements...

  18. AlGaAs/GaAs photovoltaic converters for high power narrowband radiation

    SciTech Connect (OSTI)

    Khvostikov, Vladimir; Kalyuzhnyy, Nikolay; Mintairov, Sergey; Potapovich, Nataliia; Shvarts, Maxim; Sorokina, Svetlana; Andreev, Viacheslav [Ioffe Physical-Technical Institute, 26 Polytechnicheskaya, St. Petersburg, 194021 (Russian Federation); Luque, Antonio [Ioffe Physical-Technical Institute, 26 Polytechnicheskaya, St. Petersburg, 194021, Russia and Instituto de Energia Solar, Universidad Politecnica de Madrid, Madrid (Spain)

    2014-09-26T23:59:59.000Z

    AlGaAs/GaAs-based laser power PV converters intended for operation with high-power (up to 100 W/cm{sup 2}) radiation were fabricated by LPE and MOCVD techniques. Monochromatic (? = 809 nm) conversion efficiency up to 60% was measured at cells with back surface field and low (x = 0.2) Al concentration 'window'. Modules with a voltage of 4 V and the efficiency of 56% were designed and fabricated.

  19. Catalyst and process for converting synthesis gas to liquid motor fuels

    DOE Patents [OSTI]

    Coughlin, Peter K. (Yorktown Heights, NY)

    1987-01-01T23:59:59.000Z

    The addition of an inert metal component, such as gold, silver or copper, to a Fischer-Tropsch catalyst comprising cobalt enables said catalyst to convert synthesis gas to liquid motor fuels at about 240.degree.-370.degree. C. with advantageously reduced selectivity of said cobalt for methane in said conversion. The catalyst composition can advantageously include a support component, such as a molecular sieve, co-catalyst/support component or a combination of such support components.

  20. High-efficiency, monolithic, multi-bandgap, tandem photovoltaic energy converters

    DOE Patents [OSTI]

    Wanlass, Mark W. (Golden, CO)

    2011-11-29T23:59:59.000Z

    A monolithic, multi-bandgap, tandem solar photovoltaic converter has at least one, and preferably at least two, subcells grown lattice-matched on a substrate with a bandgap in medium to high energy portions of the solar spectrum and at least one subcell grown lattice-mismatched to the substrate with a bandgap in the low energy portion of the solar spectrum, for example, about 1 eV.

  1. Clock for and CAMAC hardware for measurement of volt-amphere characteristic of thermionic converter

    SciTech Connect (OSTI)

    DZHASHIASHVILI, Yu.N.

    1986-09-01T23:59:59.000Z

    This paper describes a clock that is controlled by a computer through a CAMAC output-register module. The clock trigger the load of a thermionic converter for measurement of the volt-ampere charecteristic for 10 msec and synchronizes the start of measurement with the phase of the applied voltage. A schemitic diagram of the clock is shown. The clock increases the data-acquisition speed in successive measurement of several VACs with a limited amount of buffer memory.

  2. Thermionic converter with differentially heated cesium-oxygen source and method of operation

    SciTech Connect (OSTI)

    Rasor, Ned S. (Cupertino, CA); Riley, David R. (West Newton, PA); Murray, Christopher S. (Bethel Park, PA); Geller, Clint B. (Pittsburgh, PA)

    2000-01-01T23:59:59.000Z

    A thermionic converter having an emitter, a collector, and a source of cesium vapor is provided wherein the source of cesium vapor is differentially heated so that said source has a hotter end and a cooler end, with cesium vapor evaporating from said hotter end into the space between the emitter and the collector and with cesium vapor condensing at said cooler end. The condensed cesium vapor migrates through a porous element from the cooler end to the hotter end.

  3. Thermionic converter with differentially heated cesium-oxygen source and method of operation

    SciTech Connect (OSTI)

    Rasor, N.S.; Riley, D.R.; Murray, C.S.; Geller, C.B.

    1998-12-01T23:59:59.000Z

    A thermionic converter having an emitter, a collector, and a source of cesium vapor is provided, wherein the source of cesium vapor is differentially heated so that said source has a hotter end and a cooler end, with cesium vapor evaporating from said hotter end into the space between the emitter and the collector and with cesium vapor condensing at said cooler end. The condensed cesium vapor migrates through a porous element from the cooler end to the hotter end.

  4. A three-phase converter model for harmonic analysis of HVDC systems

    SciTech Connect (OSTI)

    Xu, W.; Drakos, J.E.; Mansour, Y.; Chang, A. (B.C. Hydro, Burnaby, British Columbia (Canada))

    1994-07-01T23:59:59.000Z

    An equivalent circuit model is presented to model bridge converters for three-phase HVDC harmonic power flow analysis. The validity and accuracy of the model are verified by comparing simulation results against field test results. The model is interfaced with a multiphase harmonic load flow program to investigate the generation of non-characteristic harmonics from HVDC links and the flow of HVDC harmonics in a real system.

  5. Multiple-band reflective polarization converter using U-shaped metamaterial

    SciTech Connect (OSTI)

    Huang, Xiaojun [College of Physical Science and Technology, Central China Normal University, Wuhan 430079 (China); Department of Physics, Kashgar Teachers College, Kashgar 844000 (China); Yang, Dong [College of Physics and Electronics Science, Hubei Normal University, Huangshi 435002 (China); Yang, Helin, E-mail: emyang@mail.ccnu.edu.cn [College of Physical Science and Technology, Central China Normal University, Wuhan 430079 (China)

    2014-03-14T23:59:59.000Z

    A multiple-band metamaterial reflective polarization converter (RPC) is proposed, which is composed of the dielectric substrate sandwiched with U-shaped metallic patterns and continuous metal film. The proposed U-shaped metamaterial RPC (UMM-RPC) can convert a linearly polarized wave to its cross polarized wave at the three resonant frequencies, which also can convert the linearly polarized wave to circularly polarized wave at other three resonant frequencies. Furthermore, the proposed UMM-RPC can maintain the same conversional direction at the three resonant frequencies when incident on a circularly polarized wave. The simulated and measured results are in agreement in the entire frequency range, and the polarization conversion ratio is over 90% for both linear and circular polarizations. The surface current distributions of the UMM-RPC are discussed to look into the physical mechanism. The proposed UMM-RPC has simple geometry but more operating frequency bands compared to the previous designs and can be used in applications such as antenna radome, remote sensors, and radiometer.

  6. Verktyg för lönsamhetsberäkningar vid bränslekonvertering av spetslastpannor från olja till pellets; Tool for estimating the profitability of converting a peak-load oil-fired boiler to pellets.

    E-Print Network [OSTI]

    Sorby, Jonathan

    2013-01-01T23:59:59.000Z

    ?? This report summarizes the development of a calculation program estimating the profitability of converting a peak-load oil-fired boiler to pellets. To convert an oil-fired… (more)

  7. Design and testing of an internal mode converter for a 1.5 MW, 110 GHz gyrotron with a depressed collector

    E-Print Network [OSTI]

    Tax, David Samuel

    We report experimental results on a 1.5 MW, 110 GHz, 3 microsecond pulsed gyrotron with a single-stage depressed collector. A simplified mode converter with smooth mirror surfaces has been installed in the tube. The converter ...

  8. The worldwide demand for green energy systems is evident. In this context, wind energy converters will play a paramount role. Extending the service life of a

    E-Print Network [OSTI]

    Stanford University

    ABSTRACT The worldwide demand for green energy systems is evident. In this context, wind energy converters will play a paramount role. Extending the service life of a wind energy converter translates and operation of the wind energy converters make it beneficial to know the structural condition

  9. Low Voltage High-SNR Pipeline Data Converters Charles Myers, Jipeng Li, Dong-Young Chang, and Un-Ku Moon

    E-Print Network [OSTI]

    Moon, Un-Ku

    Low Voltage High-SNR Pipeline Data Converters Charles Myers, Jipeng Li, Dong-Young Chang, and Un pipeline data converter. This is accomplished with the removal of the S/H input stage and the use of a rail limitations. In pipeline data converters, noise reduction options such as oversampling and noise shaping

  10. Design, improvement, and testing of a thermal-electrical analysis application of a multiple beta-tube AMTEC converter

    E-Print Network [OSTI]

    Pavlenko, Ilia V.

    2004-09-30T23:59:59.000Z

    A new design AMTEC converter model was developed, and its effectiveness as a design tool was evaluated. To develop the model, requirements of the model were defined, several new design models were successively developed, and finally an optimal new...

  11. Dynamics of a horizontal cylinder oscillating as a wave energy converter about an off-centred axis. 

    E-Print Network [OSTI]

    Lucas, Jorge

    2011-11-22T23:59:59.000Z

    The hydrodynamic properties of a horizontal cylinder which is free to pitch about an off-centred axis are studied and used to derive the equations of motion of a wave energy converter which extracts energy from incoming ...

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

    E-Print Network [OSTI]

    King Jet, TSENG

    2013-01-01T23:59:59.000Z

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

  13. A 660MHz ZVS DC-DC Converter Using Gate-Driver Charge-Recycling in 0.18m

    E-Print Network [OSTI]

    Lemieux, Guy

    allows full integration of these power supplies. To compensate for the switching power loss under high switch mode power converters, zero voltage switching (ZVS) operation is used to reduce dynamic power loss

  14. Experimental and numerical study of the behavior of three-way catalytic converters under different engine operation conditions

    E-Print Network [OSTI]

    Zhang, Yuetao

    2005-01-01T23:59:59.000Z

    The thesis reports the studies on how the three-way catalytic converters behave under different operation conditions. The main focus of the work is in the oxygen storage capacity of the three-way catalyst. Rich-to-lean ...

  15. Theoretical study of the electrical power behavior of a cesium thermionic converter for switching resistive and reactive loads

    SciTech Connect (OSTI)

    Perez, J.G. [ICUAP-BUAP, Puebla (Mexico). Semiconductor Devices Research Center; Estrada, C.A.; Jimenez, A.E.; Cervantes, J.G. [UNAM, Temixco (Mexico). Energy Research Center

    1997-12-31T23:59:59.000Z

    Pulsed ionized diodes have shown to be an attractive mode to develop thermionic converters. Usually the investigations have been focused to work with additive gases and constant loads at steady state. The experimental transient graphs reported suggest a dynamic behavior of the thermionic converter. Periods of the order of 300 {micro}s have been reported for the decay time of voltage and current, a condition that is similar to a capacitive discharge. A circuit model for a thermionic converter to define this condition is proposed. Using this model, an electrical analysis of the thermionic converter power with different switching loads is made. Both, resistive and reactive loads are connected. Special emphasis is dedicated to determine the resonance frequencies.

  16. Modelization of helio-thermal converters : application to the greenhouse effect P. Gallet, F. Papini and A. Ropke

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    169 Modelization of helio-thermal converters : application to the greenhouse effect P. Gallet, F surface - greenhouse effect association is discussed as an example. Revue Phys. Appl. 18 (1983) 169

  17. A SiC-Based Converter as a Utility Interface for a Battery System , Leon M. Tolbert1,2

    E-Print Network [OSTI]

    Tolbert, Leon M.

    , simulations of a SiC- based converter working as an interface between a battery bank and a utility were of a battery bank and a converter. The battery bank is to be charged and discharged from the utility via voltage is for M = 1. For Vll = 480 V, Vdc (min) = 783.8 V. 3 2 2 dc ll V V M= (1) B. Battery Bank

  18. A new control strategy to improve the performance of PWM ac to dc converter under unbalanced operating condition

    E-Print Network [OSTI]

    Choudhury, Shamim A.

    1992-01-01T23:59:59.000Z

    , this improved performance of the converter is not necessarily achieved. Unbalanced voltage inputs introduce a significant amount of unwanted harmonics in the input current and output voltage of the converter. These unwanted harmonics result in increased... and to develop some techniques to preserve their high performance features. This thesis. therefore. presents a new control strategy which selectively cancels the generated abnormal harmonics from the input and output waveforms without the addition of any...

  19. Functionally gradient material for membrane reactors to convert methane gas into value-added products

    DOE Patents [OSTI]

    Balachandran, Uthamalingam (Hinsdale, IL); Dusek, Joseph T. (Lombard, IL); Kleefisch, Mark S. (Napersville, IL); Kobylinski, Thadeus P. (Lisle, IL)

    1996-01-01T23:59:59.000Z

    A functionally gradient material for a membrane reactor for converting methane gas into value-added-products includes an outer tube of perovskite, which contacts air; an inner tube which contacts methane gas, of zirconium oxide, and a bonding layer between the perovskite and zirconium oxide layers. The bonding layer has one or more layers of a mixture of perovskite and zirconium oxide, with the layers transitioning from an excess of perovskite to an excess of zirconium oxide. The transition layers match thermal expansion coefficients and other physical properties between the two different materials.

  20. Experimental ferrite core circuit analysis and design applied to an analog/digital converter

    E-Print Network [OSTI]

    Hughes, Robert William

    1965-01-01T23:59:59.000Z

    EXPKRflIENTAL FERRITE CORE CIRCUIT ANALYSIS A/4i) CESIGN APPLI ED' TO AN ANALOG+I QITAL -CCWERTER I I 'O' Thaaka RCSERT, NI. LL'I AN HQQAKS:-. , ";, , '. . :. . '. -:. '"":, , ':-. ', . -' ". ' t, . I I I' I, ' . Sobalttad, ta tb ~ Qra... , Na'fir. Sabjaat& ' Eiaktr leal EnCInaaring . EXPERIIIENTAL FERRITE CORE CIRCUIT ANALYSIS AND DESIGN APPLIED TO 'AN AMALGG/DIGITAL CONVERTER f 1 A, . Thea I'a t ROBERT Wl LI. I Al'Jl. HUGHES (Goober, ) ' (Me@bar) ' A'yprived . a'o . . to a4...

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

    SciTech Connect (OSTI)

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

    1997-01-01T23:59:59.000Z

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

  2. Experimental Wave Tank Test for Reference Model 3 Floating-Point Absorber Wave Energy Converter Project

    SciTech Connect (OSTI)

    Yu, Y. H.; Lawson, M.; Li, Y.; Previsic, M.; Epler, J.; Lou, J.

    2015-01-01T23:59:59.000Z

    The U.S. Department of Energy established a reference model project to benchmark a set of marine and hydrokinetic technologies including current (tidal, open-ocean, and river) turbines and wave energy converters. The objectives of the project were to first evaluate the status of these technologies and their readiness for commercial applications. Second, to evaluate the potential cost of energy and identify cost-reduction pathways and areas where additional research could be best applied to accelerate technology development to market readiness.

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

    SciTech Connect (OSTI)

    Kemp, Mark A.; Burkhart, Craig; Nguyen, Minh N.; /SLAC; Anderson, David E.; /Oak Ridge

    2009-08-03T23:59:59.000Z

    The High Voltage Converter Modulators (HVCMs) at the Spallation Neutron Source (SNS) have operated in excess of a combined 250,000 hours. Performance and reliability improvements to the HVCM are ongoing to increase modulator availability as accelerator system demands increase. There is a relatively large amount of energy storage in the HVCMs, {approx}180 kJ. This energy has the potential to dump into unsuppressed faults, cause damage, and increase the time to repair. The 'fusing switch' concept involves isolation of this stored energy from the location of the most common faults. This paper introduces this concept and its application to the HVCMs.

  4. Functionally gradient material for membrane reactors to convert methane gas into value-added products

    DOE Patents [OSTI]

    Balachandran, U.; Dusek, J.T.; Kleefisch, M.S.; Kobylinski, T.P.

    1996-11-12T23:59:59.000Z

    A functionally gradient material for a membrane reactor for converting methane gas into value-added-products includes an outer tube of perovskite, which contacts air; an inner tube which contacts methane gas, of zirconium oxide, and a bonding layer between the perovskite and zirconium oxide layers. The bonding layer has one or more layers of a mixture of perovskite and zirconium oxide, with the layers transitioning from an excess of perovskite to an excess of zirconium oxide. The transition layers match thermal expansion coefficients and other physical properties between the two different materials. 7 figs.

  5. Analysis and design of matrix converters for adjustable speed drives and distributed power sources

    E-Print Network [OSTI]

    Cha, Han Ju

    2004-11-15T23:59:59.000Z

    .11 Comparison during power interruption (a) without ride-through module (b) with ride-through module (ch1: STPI, ch2: output current IA [5A/ div]), ch3: input voltage Vab, ch4: output line-to-line voltage VAB) .......... 70 3... bidirectional switches and each output phase is associated with three switch set connected to three input phases. This configuration of bidirectional 4 M A B C a b c SaA SbA ScA SaB SbB SbC SaC SbC ScC Fig.1.3 Matrix converter topology switches...

  6. Systems and methods for commutating inductor current using a matrix converter

    DOE Patents [OSTI]

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

    2012-10-16T23:59:59.000Z

    Systems and methods are provided for delivering current using a matrix converter in a vehicle. An electrical system comprises an AC interface, a first conversion module coupled to the AC interface, an inductive element coupled between the AC interface and the first conversion module, and a control module coupled to the first conversion module. The control module is configured to operate the first conversion module in a bidirectional operating mode to commutate current bidirectionally. When a magnitude of the current through the inductive element is greater than a first threshold value, the control module operates the conversion module in a unidirectional operating mode, wherein current is commutated unidirectionally.

  7. Process and catalyst for converting synthesis gas to liquid hydrocarbon mixture

    DOE Patents [OSTI]

    Rao, V. Udaya S. (Monroeville, PA); Gormley, Robert J. (Pittsburgh, PA)

    1987-01-01T23:59:59.000Z

    Synthesis gas containing CO and H.sub.2 is converted to a high-octane hydrocarbon liquid in the gasoline boiling point range by bringing the gas into contact with a heterogeneous catalyst including, in physical mixture, a zeolite molecular sieve, cobalt at 6-20% by weight, and thoria at 0.5-3.9% by weight. The contacting occurs at a temperature of 250.degree.-300.degree. C., and a pressure of 10-30 atmospheres. The conditions can be selected to form a major portion of the hydrocarbon product in the gasoline boiling range with a research octane of more than 80 and less than 10% by weight aromatics.

  8. Process for converting heavy oil deposited on coal to distillable oil in a low severity process

    DOE Patents [OSTI]

    Ignasiak, Teresa (417 Heffernan Drive, Edmonton, Alberta, CA); Strausz, Otto (13119 Grand View Drive, Edmonton, Alberta, CA); Ignasiak, Boleslaw (417 heffernan Drive, Edmonton, Alberta, CA); Janiak, Jerzy (17820 - 76 Ave., Edmonton, Alberta, CA); Pawlak, Wanda (3046 - 11465 - 41 Avenue, Edmonton, Alberta, CA); Szymocha, Kazimierz (3125 - 109 Street, Edmonton, Alberta, CA); Turak, Ali A. (Edmonton, CA)

    1994-01-01T23:59:59.000Z

    A process for removing oil from coal fines that have been agglomerated or blended with heavy oil comprises the steps of heating the coal fines to temperatures over 350.degree. C. up to 450.degree. C. in an inert atmosphere, such as steam or nitrogen, to convert some of the heavy oil to lighter, and distilling and collecting the lighter oils. The pressure at which the process is carried out can be from atmospheric to 100 atmospheres. A hydrogen donor can be added to the oil prior to deposition on the coal surface to increase the yield of distillable oil.

  9. Method of converting an existing vehicle powertrain to a hybrid powertrain system

    DOE Patents [OSTI]

    Reed, Jr., Richard G. (Royal Oak, MI); Boberg, Evan S. (Hazel Park, MI); Lawrie, Robert E. (Whitmore Lake, MI); Castaing, Francois J. (Bloomfield Township, MI)

    2001-12-25T23:59:59.000Z

    A method of converting an existing vehicle powertrain including a manual transmission to a hybrid powertrain system with an automated powertrain transmission. The first step in the method of attaching a gear train housing to a housing of said manual transmission, said gear train housing receiving as end of drive shaft of said transmission and rotatably supporting a gear train assembly. Secondly, mounting an electric motor/generator to said gear train housing and attaching a motor/generator drive shaft of said electric motor/generator to said gear train assembly. Lastly, connecting an electro-mechanical clutch actuator to a friction clutch mechanism of said manual transmission.

  10. Design and Analysis for a Floating Oscillating Surge Wave Energy Converter: Preprint

    SciTech Connect (OSTI)

    Yu, Y. H.; Li, Y.; Hallett, K.; Hotimsky, C.

    2014-03-01T23:59:59.000Z

    This paper presents a recent study on the design and analysis of an oscillating surge wave energy converter. A successful wave energy conversion design requires the balance between the design performance and cost. The cost of energy is often used as the metric to judge the design of the wave energy conversion system. It is often determined based on the device power performance, the cost for manufacturing, deployment, operation and maintenance, as well as the effort to ensure the environmental compliance. The objective of this study is to demonstrate the importance of a cost driven design strategy and how it can affect a WEC design. Three oscillating surge wave energy converter (OSWEC) designs were used as the example. The power generation performance of the design was modeled using a time-domain numerical simulation tool, and the mass properties of the design were determined based on a simple structure analysis. The results of those power performance simulations, the structure analysis and a simple economic assessment were then used to determine the cost-efficiency of selected OSWEC designs. Finally, a discussion on the environmental barrier, integrated design strategy and the key areas that need further investigation is also presented.

  11. Analysis of instability growth and collisionless relaxation in thermionic converters using 1-D PIC simulations

    SciTech Connect (OSTI)

    Kreh, B.B.

    1994-12-01T23:59:59.000Z

    This work investigates the role that the beam-plasma instability may play in a thermionic converter. The traditional assumption of collisionally dominated relaxation is questioned, and the beam-plasma instability is proposed as a possible dominant relaxation mechanism. Theory is developed to describe the beam-plasma instability in the cold-plasma approximation, and the theory is tested with two common Particle-in-Cell (PIC) simulation codes. The theory is first confirmed using an unbounded plasma PIC simulation employing periodic boundary conditions, ES1. The theoretically predicted growth rates are on the order of the plasma frequencies, and ES1 simulations verify these predictions within the order of 1%. For typical conditions encountered in thermionic converters, the resulting growth period is on the order of 7 {times} 10{sup {minus}11} seconds. The bounded plasma simulation PDP1 was used to evaluate the influence of finite geometry and the electrode boundaries. For this bounded plasma, a two-stream interaction was supported and resulting in nearly complete thermalization in approximately 5 {times} 10{sup {minus}10} seconds. Since the electron-electron collision rate of 10{sup 9} Hz and the electron atom collision rate of 10{sup 7} Hz are significantly slower than the rate of development of these instabilities, the instabilities appear to be an important relaxation mechanism.

  12. Baseline Design of a Solid Neutron Converter Driven by 160 MeV Protons

    E-Print Network [OSTI]

    Herrera-Martínez, A

    2006-01-01T23:59:59.000Z

    The European Isotope Separation On-Line Radioactive Ion Beam Facility Design Study (EURISOL DS) aims at the design of several spallation and fission targets for the production of radioactive isotopes. Namely, direct targets, where high-energy protons interact directly with the fission targets, as well as the design of a Multi-MW proton-to-neutron converter coupled with a fission target. For the later, several options have been proposed, including the use of a relatively low energy (in the hundreds of MeV) high intensity proton beam. In this scope, the neutronic characteristics of a tantalum n-converter/fission-target system have been established (although not yet optimised) for a reference proton energy of 160 MeV. A set of simulations has been carried out for different design requirements and different characteristics of the proton beam. An extensive comparison of the main physical parameters has also been carried out, in order to allow the optimal engineering design of the whole target station.

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

    SciTech Connect (OSTI)

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

    1998-12-31T23:59:59.000Z

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

  14. Methods of chemically converting first materials to second materials utilizing hybrid-plasma systems

    DOE Patents [OSTI]

    Kong, Peter C. (Idaho Falls, ID); Grandy, Jon D. (Idaho Falls, ID)

    2002-01-01T23:59:59.000Z

    In one aspect, the invention encompasses a method of chemically converting a first material to a second material. A first plasma and a second plasma are formed, and the first plasma is in fluid communication with the second plasma. The second plasma comprises activated hydrogen and oxygen, and is formed from a water vapor. A first material is flowed into the first plasma to at least partially ionize at least a portion of the first material. The at least partially ionized first material is flowed into the second plasma to react at least some components of the first material with at least one of the activated hydrogen and activated oxygen. Such converts at least some of the first material to a second material. In another aspect, the invention encompasses a method of forming a synthetic gas by flowing a hydrocarbon-containing material into a hybrid-plasma system. In yet another aspect, the invention encompasses a method of degrading a hydrocarbon-containing material by flowing such material into a hybrid-plasma system. In yet another aspect, the invention encompasses a method of releasing an inorganic component of a complex comprising the inorganic component and an other component, wherein the complex is flowed through a hybrid-plasma system.

  15. Options for converting excess plutonium to feed for the MOX fuel fabrication facility

    SciTech Connect (OSTI)

    Watts, Joe A [Los Alamos National Laboratory; Smith, Paul H [Los Alamos National Laboratory; Psaras, John D [Los Alamos National Laboratory; Jarvinen, Gordon D [Los Alamos National Laboratory; Costa, David A [Los Alamos National Laboratory; Joyce, Jr., Edward L [Los Alamos National Laboratory

    2009-01-01T23:59:59.000Z

    The storage and safekeeping of excess plutonium in the United States represents a multibillion-dollar lifecycle cost to the taxpayers and poses challenges to National Security and Nuclear Non-Proliferation. Los Alamos National Laboratory is considering options for converting some portion of the 13 metric tons of excess plutonium that was previously destined for long-term waste disposition into feed for the MOX Fuel Fabrication Facility (MFFF). This approach could reduce storage costs and security ri sks, and produce fuel for nuclear energy at the same time. Over the course of 30 years of weapons related plutonium production, Los Alamos has developed a number of flow sheets aimed at separation and purification of plutonium. Flow sheets for converting metal to oxide and for removing chloride and fluoride from plutonium residues have been developed and withstood the test oftime. This presentation will address some potential options for utilizing processes and infrastructure developed by Defense Programs to transform a large variety of highly impure plutonium into feedstock for the MFFF.

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

    SciTech Connect (OSTI)

    Jason Lai

    2009-03-03T23:59:59.000Z

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

  17. 3-Port Single-Stage PV & Battery Converter Improves Efficiency and Cost in Combined PV/Battery Systems

    SciTech Connect (OSTI)

    Bundschuh, Paul [Ideal Power

    2013-03-23T23:59:59.000Z

    Due to impressive cost reductions in recent years, photovoltaic (PV) generation is now able to produce electricity at highly competitive prices, but PV’s inherent intermittency reduces the potential value of this energy. The integration of battery storage with PV will be transformational by increasing the value of solar. Utility scale systems will benefit by firming intermittency including PV ramp smoothing, grid support and load shifting, allowing PV to compete directly with conventional generation. For distributed grid-tied PV adding storage will reduce peak demand utility charges, as well as providing backup power during power grid failures. The largest long term impact of combined PV and battery systems may be for delivering reliable off-grid power to the billions of individuals globally without access to conventional power grids, or for billions more that suffer from daily power outages. PV module costs no longer dominate installed PV system costs. Balance-of-System (BOS) costs including the PV inverter and installation now contribute the majority of installed system costs. Battery costs are also dropping faster than installation and battery power converter systems. In each of these separate systems power converters have become a bottleneck for efficiency, cost and reliability. These bottlenecks are compounded in hybrid power conversion systems that combine separate PV and battery converters. Hybrid power conversion systems have required multiple power converters hardware units and multiple power conversion steps adding to efficiency losses, product and installation costs, and reliability issues. Ideal Power Converters has developed and patented a completely new theory of operation for electronic power converters using its indirect EnergyPacket Switching™ topology. It has established successful power converter products for both PV and battery systems, and its 3-Port Hybrid Converter is the first product to exploit the topology’s capability for the industry’s first single-stage multi-port hybrid power converter. This unique low cost approach eliminates the hybrid power conversion bottlenecks when integrating batteries into PV systems. As result this product will significantly accelerate market adoption of these systems.

  18. Converting Boundary Representation Solid Models to Half-Space Representation Models for Monte Carlo Analysis

    SciTech Connect (OSTI)

    Davis JE, Eddy MJ, Sutton TM, Altomari TJ

    2007-03-01T23:59:59.000Z

    Solid modeling computer software systems provide for the design of three-dimensional solid models used in the design and analysis of physical components. The current state-of-the-art in solid modeling representation uses a boundary representation format in which geometry and topology are used to form three-dimensional boundaries of the solid. The geometry representation used in these systems is cubic B-spline curves and surfaces--a network of cubic B-spline functions in three-dimensional Cartesian coordinate space. Many Monte Carlo codes, however, use a geometry representation in which geometry units are specified by intersections and unions of half-spaces. This paper describes an algorithm for converting from a boundary representation to a half-space representation.

  19. Wave Energy Converter (WEC) Array Effects on Wave Current and Sediment Circulation: Monterey Bay CA.

    SciTech Connect (OSTI)

    Roberts, Jesse D.; Jones, Craig; Magalen, Jason

    2014-09-01T23:59:59.000Z

    The goal s of this study were to develop tools to quantitatively characterize environments where wave energy converter ( WEC ) devices may be installed and to assess e ffects on hydrodynamics and lo cal sediment transport. A large hypothetical WEC array was investigated using wave, hydrodynamic, and sediment transport models and site - specific average and storm conditions as input. The results indicated that there were significant changes in sediment s izes adjacent to and in the lee of the WEC array due to reduced wave energy. The circulation in the lee of the array was also altered; more intense onshore currents were generated in the lee of the WECs . In general, the storm case and the average case show ed the same qualitative patterns suggesting that these trends would be maintained throughout the year. The framework developed here can be used to design more efficient arrays while minimizing impacts on nearshore environmen ts.

  20. Process for Converting Waste Glass Fiber into Value Added Products, Final Report

    SciTech Connect (OSTI)

    Hemmings, Raymond T.

    2005-12-31T23:59:59.000Z

    Nature of the Event: Technology demonstration. The project successfully met all of its technical objectives. Albacem has signed an exclusive licensing agreement with Vitro Minerals Inc., a specialty minerals company, to commercialize the Albacem technology (website: www.vitrominerals.com). Location: The basic research for the project was conducted in Peoria, Illinois, and Atlanta, Georgia, with third-party laboratory verification carried out in Ontario, Canada. Pilot-scale trials (multi-ton) were conducted at a facility in South Carolina. Full-scale manufacturing facilities have been designed and are scheduled for construction by Vitro Minerals during 2006 at a location in the Georgia, North Carolina, and South Carolina tri-state area. The Technology: This technology consists of a process to eliminate solid wastes generated at glass fiber manufacturing facilities by converting them to value-added materials (VCAS Pozzolans) suitable for use in cement and concrete applications. This technology will help divert up to 250,000 tpy of discarded glass fiber manufacturing wastes into beneficial use applications in the concrete construction industry. This technology can also be used for processing glass fiber waste materials reclaimed from monofills at manufacturing facilities. The addition of take-back materials and reclamation from landfills can help supply over 500,000 tpy of glass fiber waste for processing into value added products. In the Albacem process, waste glass fiber is ground to a fine powder that effectively functions as a reactive pozzolanic admixture for use in portland ce¬ment-based building materials and products, such as concrete, mortars, terrazzo, tile, and grouts. Because the waste fiber from the glass manufacturing industry is vitreous, clean, and low in iron and alkalis, the resulting pozzolan is white in color and highly consistent in chemical composition. This white pozzolan, termed VCAS Pozzolan (for Vitreous Calcium-Alumino-Silicate). is especially suited for white concrete applications where it imparts desirable benefits such as increased long-term strength and improved long-term durability of concrete products. Two U.S. patents entitled have been issued to Albacem covering the technology. Third-party validation testing has confirmed that the pozzolanic product is an excellent, high performance material that conforms to a ASTM standards and improves the strength and durability of concrete. Currently, there are no known significant competing technologies to process glass fiber manufacturing by-products and con¬vert them into value-added products. Most glass fiber-forming and fabrication wastes continue to be disposed in landfills at significant costs and with associated negative environmental impact. It is estimated that in a typical glass fiber manufactur¬ing facility, 10-20% by weight of the processed glass material is sent for dis¬posal to a landfill. Today, supplementary ce¬menting materials or mineral admixtures are key to achieving strong and durable concrete. Recovered materials such as coal fly ash, ground granulated blast furnace slag and silica fume are widely accepted and used in concrete all over the world, espe¬cially in the construction of “high performance” structures such as massive dams, bridges, subway tunnels, etc. These min¬eral admixtures are not suitable for white concrete and light-colored architectural concrete applications. Converting waste glass fibers into a high performance white pozzolan would allow white concrete producers to gain from the same durability benefits currently realized by gray concrete producers. Description of the Benefit: Albacem’s technology will enable the glass fiber industry to eliminate nearly 100% of its glass fiber produc¬tion waste streams by converting them into viable value-added products. With this technology, the glass industry can prevent the landfilling of about 250,000 tons of waste glass fiber annually. Glass manufacturers will realize improved production efficiency by reducing process costs through the elimination of solid was

  1. Thermal analysis of the ATI thermionic converter for optimum cesium reservoir location

    SciTech Connect (OSTI)

    Young, T.J. (Aerospace Power Division, Wright Laboratory/POOC, Wright-Patterson AFB, Ohio 45433-6563 (United States)); Thayer, K.L.; Ramalingam, M.L. (UES, Inc., 4401 Dayton-Xenia Road, Dayton, Ohio 45432-1894 (United States))

    1993-01-15T23:59:59.000Z

    A first-order thermal analysis was performed on the emitter lead region of the Advanced Thermionic Initiative (ATI) Thermionic Fuel Element (TFE) design. The lead region is the candidate location for a metal-matrix, cesium-graphite reservoir to supply cesium vapor to the thermionic converter. The cesium pressure developed is dependent upon the temperature and cesium-carbon equilibrium reaction of the reservoir. Steady-state, one dimensional conduction, with thermal radiation losses and Joulean heat generation, was used to calculate the temperature distribution in the non-fueled lead region. This temperature distribution was linked to the ATI reactor core design through the integration of axial emitter temperature distributions for the maximum, minimum, and average power TFE fuel pins. The axial temperature distribution in the emitter lead region was found to be most pronounced for the maximum power fuel element and least pronounced for the minimum power TFE.

  2. Efficient binary sources of working-body vapor for thermionic converters

    SciTech Connect (OSTI)

    Kalandarishvili, A.G.; Kashiya, V.G.

    1994-06-01T23:59:59.000Z

    The objective of this investigation was an experimental determination of the parameters of a cylindrical thermionic converter (TC), with the binary system being cesium with bismuth, antimony, selenium, and germanium. In all devices, the emitter was a layer of tungsten, and the collector consisted of niobium or an alloy of molybdenum with ruthenium. The system characteristics of each binary system were studied, with the interaction kinetics of the cesium vapor with the active sorbent being examined by the gravimetric method. For each TC, the current-voltage characteristics were investigated as was the work function. For each case investigated, there was a 25-30% higher TC power output due to the presence of the active additive.

  3. Design of HVDC converter stations with respect to audible noise requirements

    SciTech Connect (OSTI)

    Smede, J.; Johansson, C.G.; Winroth, O. [ASEA Brown Boveri, Vaesteraas (Sweden)] [ASEA Brown Boveri, Vaesteraas (Sweden); Schuett, H.P. [ASEA Brown Boveri, Ludvika (Sweden)] [ASEA Brown Boveri, Ludvika (Sweden)

    1995-04-01T23:59:59.000Z

    The purpose of this paper is to provide an overview of the engineering methods, tools, design solutions and verification methods used in the design of HVDC converter stations subject to acoustic requirements. The sound generation part describes how the sound power level radiated from electrical components can be calculated based on the load. The sound propagation part describes how the sources are affecting the sound pressure level at emission points of interest. A method to break down the acoustic requirement to component level and practical studies to verify the concordance with the requirements are also illustrated. Different solutions for screening and absorption are described as well as measurement methods. The remainder describes a working method used to fulfill outdoor acoustic requirements.

  4. Note: Increasing dynamic range of digital-to-analog converter using a superconducting quantum interference device

    SciTech Connect (OSTI)

    Nakanishi, Masakazu, E-mail: m.nakanishi@aist.go.jp [Metrology Institute of Japan, National Institute of Advanced Industrial Science and Technology, AIST Central-3, 1-1, Umezono, Tsukuba, Ibaraki 305-8563 (Japan)

    2014-10-15T23:59:59.000Z

    Responses of a superconducting quantum interference device (SQUID) are periodically dependent on magnetic flux coupling to its superconducting ring and the period is a flux quantum (?{sub o} = h/2e, where h and e, respectively, express Planck's constant and elementary charge). Using this periodicity, we had proposed a digital to analog converter using a SQUID (SQUID DAC) of first generation with linear current output, interval of which corresponded to ?{sub o}. Modification for increasing dynamic range by interpolating within each interval is reported. Linearity of the interpolation was also based on the quantum periodicity. A SQUID DAC with dynamic range of about 1.4 × 10{sup 7} was created as a demonstration.

  5. Photovoltaic power converter system with a controller configured to actively compensate load harmonics

    DOE Patents [OSTI]

    de Rooij, Michael Andrew (Clifton Park, NY); Steigerwald, Robert Louis (Burnt Hills, NY); Delgado, Eladio Clemente (Burnt Hills, NY)

    2008-12-16T23:59:59.000Z

    Photovoltaic power converter system including a controller configured to reduce load harmonics is provided. The system comprises a photovoltaic array and an inverter electrically coupled to the array to generate an output current for energizing a load connected to the inverter and to a mains grid supply voltage. The system further comprises a controller including a first circuit coupled to receive a load current to measure a harmonic current in the load current. The controller includes a second circuit to generate a fundamental reference drawn by the load. The controller further includes a third circuit for combining the measured harmonic current and the fundamental reference to generate a command output signal for generating the output current for energizing the load connected to the inverter. The photovoltaic system may be configured to compensate harmonic currents that may be drawn by the load.

  6. Improvement of photovoltaic pumping systems based on standard frequency converters by means of programmable logic controllers

    SciTech Connect (OSTI)

    Fernandez-Ramos, Jose [Departamento de Electronica, Universidad de Malaga, Complejo Tecnologico de Teatinos (2.2.39), 29071 Malaga (Spain); Narvarte-Fernandez, Luis; Poza-Saura, Fernando [Instituto de Energia Solar, Universidad Politecnica de Madrid (IES-UPM), Avenida Complutense s/n (204), 28040 Madrid (Spain)

    2010-01-15T23:59:59.000Z

    Photovoltaic pumping systems (PVPS) based on standard frequency converters (SFCs) are currently experiencing a growing interest in pumping programmes implemented in remote areas because of their high performance in terms of component reliability, low cost, high power range and good availability of components virtually anywhere in the world. However, in practical applications there have appeared a number of problems related to the adaptation of the SFCs to the requirements of the photovoltaic pumping systems (PVPS). Another disadvantage of dedicated PVPS is the difficulty in implementing maximum power point tracking (MPPT). This paper shows that these problems can be solved through the addition of a basic industrial programmable logic controller (PLC) to the system. This PLC does not increase the cost and complexity of the system, but improves the adaptation of the SFC to the photovoltaic pumping system, and increases the overall performance of the system. (author)

  7. Effect of updated data base and improved analysis on performance of radioisotope thermophotovoltaic converter

    SciTech Connect (OSTI)

    Schock, A.; Or, C.T. [Orbital Sciences Corp., Germantown, MD (United States)

    1996-12-31T23:59:59.000Z

    Previous analyses of RTPV space power systems published by the authors were based on a number of approximations employed to permit early dissemination of preliminary results pending availability of fuller experimental data need3d to conduct more rigorous analyses. Among those approximations were: (1) the use of limited test data and optimistic projections of the spectral transmissivity of the RTPV`s selective IR filters and of the spectral quantum efficiency of the GaSb PV cells; (2) the use of theoretical formulas instead of experimental measurements of the PV cell`s open-circuit voltage, fill factor, and optimum voltage instead of its measured current-voltage characteristics; (3) rough estimates of the TPV converter`s active-area fraction instead of computed values based on detailed designs; (4) inadequate accounting for the effect of radiation reflected by the IR filter and absorbed by the emitter in reducing the generator`s required heat input; and (5) omission of the shadowing effect and ohmic losses caused by the PV cell`s grid lines. The above-listed shortcomings of the previously published analyses are addressed in the present paper, which describes revised analyses based on recently obtained experimental data of IR filter reflectivities and PV cell quantum efficiencies and current-voltage characteristic, measured by EDTEK under an OSC-initiated subcontract to its ongoing DOE contract. Their test results show that EDTEK has been eminently successful in improving the reflectivities of the IR filters and in reproducing the quantum efficiencies of Boeing`s best PV cells, but their initial (Dec-95) PV cell fell far short of matching the open-circuit voltages and fill factors predicted by theory.

  8. New approaches for the reduction of plasma arc drop in second-generation thermionic converters. Final report

    SciTech Connect (OSTI)

    Hatziprokopiou, M.E.; Shaw, D.T.

    1981-03-31T23:59:59.000Z

    Investigations of ion generation and recombination mechanisms in the cesium plasma as they pertain to the advanced mode thermionic energy converter are described. The changes in plasma density and temperature within the converter have been studied under the influence of several promising auxiliary ionization candidate sources. Three novel approaches of external cesium ion generation have been investigated in some detail, namely vibrationally excited N/sub 2/ as an energy source of ionization of Cs ions in a DC discharge, microwave power as a means of resonant sustenance of the cesium plasma, and ion generation in a pulse N/sub 2/-Cs mixture. The experimental data obtained and discussed show that all three techniques - i.e. the non-LTE high-voltage pulsing, the energy transfer from vibrationally excited diatomic gases, and the external pumping with a microwave power - have considerable promise as schemes in auxiliary ion generation applicable to the advanced thermionic energy converter.

  9. Monolithic phosphor-free InGaN/GaN quantum dot wavelength converter white light emitting diodes

    SciTech Connect (OSTI)

    Jahangir, Shafat; Bhattacharya, Pallab, E-mail: pkb@eecs.umich.edu [Center for Photonics and Multiscale Nanomaterials, Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, Michigan 48109-2122 (United States); Pietzonka, Ines; Strassburg, Martin [OSRAM Opto Semiconductors GmbH, Leibnizstrasse 4, Regensburg (Germany)

    2014-09-15T23:59:59.000Z

    We report the characteristics of phosphor-free self-organized InGaN/GaN quantum dot wavelength converter white light emitting diodes grown by plasma assisted molecular beam epitaxy. The exciting quantum dots, in which electrically injected carriers recombine, are blue-emitting and the converter dots are red-emitting. We have studied the effect of tuning the number of dot layers and the peak emission wavelength of the exciting and converter dots on the nature of the emitted white light, in terms of the chromaticity coordinates and correlated color temperature. Depending on the values of these wavelengths, color temperatures in the range of 4420–6700?K have been derived at a current density of 45?A/cm{sup 2} across multiple devices. The variation of the color temperature with change in injection current is found to be very small.

  10. Use of reagents to convert chrysotile and amosite asbestos used as insulation or protection for metal surfaces

    DOE Patents [OSTI]

    Sugama, Toshifumi (Wading River, NY); Petrakis, Leon (Port Jefferson, NY)

    2000-12-12T23:59:59.000Z

    A composition for converting asbestos-containing material, covering metal pipes or other metal surfaces, to non-regulated, environmentally benign-materials, and inhibiting the corrosion of the metal pipes or other metal surfaces. The composition comprises a combination of at least two multiple-functional group reagents, in which each reagent includes a Fluro acid component and a corrosion inhibiting compoment. A method for converting asbestos-containing material, covering metal pipes or other metal surfaces, to non-regulated, environmentally benign-materials, and inhibiting the corrosion of the metal pipes or other metal surfaces is also provided.

  11. Thermal conductivity of the electrode gap of a therminonic converter, filled with inert gases, at low pressures

    SciTech Connect (OSTI)

    Modin, V.A.; Nikolaev, Y.V.

    1986-05-01T23:59:59.000Z

    This paper presents experimental data on the thermal conductivity of the electrode gap of a thermionic converter filled with He, Ar, and Xe in the pessure range 40-550 Pa. The need to account for the coefficients of thermal accomodation of the emitter-inert-gas-collector system in this range is shown. The accomodation coefficients for different temperature regimes are measured and expressions are obtained to calculate the heat flux transported by the inert gases in the electrode gap. A diagram of the experimental thermionic converter is shown.

  12. Thermionic-combustor combined-cycle system. Volume III. A thermionic converter design for gas-turbine combined-cycle systems

    SciTech Connect (OSTI)

    Fitzpatrick, G.O.; Britt, E.J.; Dick, R.S. Jr.

    1981-05-01T23:59:59.000Z

    Thermionic converter design is strongly influenced by the configuration of the heat source and heat sink. These two externally imposed conditions are of major importance in arriving at a viable converter design. In addition to these two factors, the economical and reliable transfer of energy internally within the converter is another major item in the design. The effects of the engineering trade-offs made in arriving at the design chosen for the Gas Turbine Combined Cycle combustor are reviewed.

  13. Contribution of nano-scale effects to the total efficiency of converters of thermal neutrons on the basis of gadolinium foils

    E-Print Network [OSTI]

    D. A. Abdushukurov; D. V. Bondarenko; Kh. Kh. Muminov; D. Yu. Chistyakov

    2008-02-04T23:59:59.000Z

    We study the influence of nano-scale layers of converters made from natural gadolinium and its 157 isotope into the total efficiency of registration of thermal neutrons. Our estimations show that contribution of low-energy Auger electrons with the runs about nanometers in gadolinium, to the total efficiency of neutron converters in this case is essential and results in growth of the total efficiency of converters. The received results are in good consent to the experimental data.

  14. Intentional Islanded Operation of Converter Fed Microgrids Charles K. Sao, Student Member, IEEE, and Peter W. Lehn, Member, IEEE

    E-Print Network [OSTI]

    Lehn, Peter W.

    1 Intentional Islanded Operation of Converter Fed Microgrids Charles K. Sao, Student Member, IEEE microgrid and proposes a control scheme to regulate its voltage and frequency. The model, which is formulated in an instantaneously synchro- nized reference frame, shows that the microgrid voltage depends

  15. An Algorithm to Convert Wafer to Calendar-Based Preventive Maintenance Schedules for Semiconductor Manufacturing Systems1

    E-Print Network [OSTI]

    Fernandez, Emmanuel

    An Algorithm to Convert Wafer to Calendar-Based Preventive Maintenance Schedules for Semiconductor}@ececs.uc.edu Abstract-- The work presented here is related to the area of Optimal Preventive Maintenance (PM) Scheduling. Preventive Maintenance (PM) is a standard practice followed to increase reliability and availability

  16. 36 IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS, VOL. 35, NO. 1, JANUARY/FEBRUARY 1999 Multilevel Converters for Large Electric Drives

    E-Print Network [OSTI]

    Tolbert, Leon M.

    Converters for Large Electric Drives Leon M. Tolbert, Senior Member, IEEE, Fang Zheng Peng, Senior Member multilevel con- verters as an application for high-power and/or high-voltage electric motor drives all-electric drives because it uses several levels of dc voltage sources, which would be available

  17. Development of electron reflection suppression materials for improved thermionic energy converter performance using thin film deposition techniques

    SciTech Connect (OSTI)

    Islam, Mohammad; Inal, Osman T.; Luke, James R. [Department of Materials and Metallurgical Engineering, New Mexico Institute of Mining and Technology, Socorro, New Mexico 87801 (United States); New Mexico Institute of Mining and Technology, Institute for Engineering Research and Applications (IERA) , 901 University Blvd. SE, Albuquerque, New Mexico 87106-4339 (United States)

    2006-10-15T23:59:59.000Z

    Nonideal electrode surfaces cause significant degree of electron reflection from collector during thermionic converter operation. The effect of the collector surface structure on the converter performance was assessed through the development of several electron reflection suppression materials using various thin film deposition techniques. The double-diode probe method was used to compare the J-V characteristics of converters with polished and modified collector surfaces for emitter temperature and cesium vapor pressure in the ranges of 900-2000 K and 0.02-1.5 torr, respectively. The coadsorption of cesium and oxygen with respective partial vapor pressures of {approx}1.27 torr and a few microtorrs reduced the emitter work function to a minimum value of 0.99 eV. It was found that the collector surfaces with matte black appearance such as platinum black, voided nickel from radio-frequency plasma sputtering, and etched electroless Ni-P with craterlike pore morphology exhibited much better performance compared with polished collector surface. For these thin films, the increase in the maximum output voltage was up to 2.0 eV. For optimum performance with minimum work function and maximum saturation emission current density, the emitter temperature was in the range of 1100-1500 K, depending on the collector surface structure. The use of these materials in cylindrical converter design and/or in combination with hybrid mode triode configuration holds great potential in low and medium scale power generators for commercial use.

  18. NATURE MATERIALS | VOL 13 | MARCH 2014 | www.nature.com/naturematerials 233 hotovoltaic devices --which convert abundant, free solar

    E-Print Network [OSTI]

    - and downconversion11 , technologies that, like the multi-junction strategy, offer a roadmap beyond the Shockley dot photovoltaics Xinzheng Lan1,2 , Silvia Masala1,3 and Edward H. Sargent1 * The solar -- which convert abundant, free solar radiation into electric power -- are increasingly required to offer

  19. Digital Loss-Minimizing Multi-Mode Synchronous Buck Converter Control Angel V. Peterchev Seth R. Sanders

    E-Print Network [OSTI]

    Sanders, Seth

    transition among the modes. An on-line adaptive algorithm to optimize the SR timing, based on power loss reducing the switching losses. In modern portable applications, minimizing power loss at light load in the controller, or can be obtained on-line by dynamically minimizing the converter power loss via multi

  20. Abstract --When a real time digital simulator, emulating a switched circuit such as a voltage source converter, is interfaced

    E-Print Network [OSTI]

    Lehn, Peter W.

    1 Abstract -- When a real time digital simulator, emulating a switched circuit such as a voltage source converter, is interfaced with a digital controller, the controller's firing signals may. Incorrect power flow due to inaccurate firing times and controller errors. 2. Switching jitter due

  1. DA/MA: Multi-objective optimization of LCC resonant converter applied in high-voltage generator

    E-Print Network [OSTI]

    Paderborn, Universität

    , transformer, and a cascaded rectifier, is shown below. Particular task of this project is to reduce power losses, volume, and stress of the components with the designated input and output specifications and the analytical converter large-signal model. Expected study and research work includes: · Extend the power loss

  2. Harmonic Optimization of Multilevel Converters Using Genetic Algorithms Abstract--In this paper, a genetic algorithm (GA) optimization

    E-Print Network [OSTI]

    Tolbert, Leon M.

    to the fact that several batteries, fuel cells, solar cell, wind, and microturbines can be connected through Vao Fuel Cell Module a o Fuel Cell Module Fuel Cell Module Q11 D11 Q12 D12 Q13 D13Q14 D14 Q21 Q22 D22Harmonic Optimization of Multilevel Converters Using Genetic Algorithms Abstract-- In this paper

  3. The neutron-physical aspects of the converter reactor with single-element TFE. [ZrH; Be; Al; U

    SciTech Connect (OSTI)

    Glushkov, E.S.; Kompanietz, G.V.; Kosovskii, V.G.; Kukharkin, N.E.; Ponomarev-Stepnoi, N.N.; Smirnov, O.N.; Usov, V.A. (Khurchatov Institute of Atomic Energy, Moscow, USSR (US))

    1991-01-05T23:59:59.000Z

    This paper presents a discussion of the main parameters of a thermionic converter reactor with zirconium hydride moderator using a single-element fuel element built into the core. Power distribution of the thermionic fuel element, reactivity changes with time, temperature effects and power density were investigated with Monte Carlo calculations. (AIP)

  4. SESSION IO: Analogto-Digital Converters TPM 10.6: An18b lops Self-calibratingADC

    E-Print Network [OSTI]

    Lee, Hae-Seung "Harry"

    on this chip includes calibration pattern generaton, a successive approx- imation register (SAR), elementsSESSION IO: Analogto-Digital Converters TPM 10.6: An18b lops Self-calibratingADC Gerald, Miller Wilmington, MA AUTO-CALIBRATION has been used in monolithic ADCs to extend the limits of accuracy

  5. Design of a Modular Multilevel Converter as an Active Front-End for a magnet supply application

    E-Print Network [OSTI]

    Panagiotis, Asimakopoulos; Massimo, Bongiorno

    2015-01-01T23:59:59.000Z

    The aim of this work is to describe the general design procedure of a Modular Multilevel Converter (MMC) applied as an Active Front-End (AFE) for a magnet supply for beam accelerators. The dimensioning criteria for the converter and the dc-link capacitance are presented and the grid transformer requirements are set. Considering the converter design, the arm inductance calculation is based on the specifications for the arm-current ripple and the DC-link fault tolerance, but, also, on the limitation of the second harmonic and the second-order LC resonance of the arm current. The module capacitance value is evaluated by focusing on the required switching dynamics and the capacitor-voltage ripple according to a newly proposed graphical method. The loading of each semiconductor in the half bridge is calculated via simulation, indicating the unsymmetrical current distribution. It is concluded that the current distribution for each semiconductor depends on the mode of operation of the converter. The different criter...

  6. Basement Imaging Using Sp Converted Phases from a Dense Strong-Motion Array in Lan-Yang Plain, Taiwan

    E-Print Network [OSTI]

    Wu, Yih-Min

    the convert- ing point is at the unconsolidated Quaternary alluvial sediments­Miocene basement interface. Our characteristics of velocity/thickness structure of a study area. Introduction It is well known that unconsolidated the Cenozoic unconsolidated sedi- ments and the underlying rocks have also been studied to constrain

  7. HOW DO WE CONVERT THE TRANSPORT SECTOR TO RENEWABLE ENERGY AND IMPROVE THE SECTOR'S INTERPLAY WITH THE

    E-Print Network [OSTI]

    ..........................................................................................................16 #12;2 1. Summary The global energy scene is currently dominated by two overriding concerns relies almost 100 % on oil, and in 2004 transport energy use amounted to 26% of total world energy useHOW DO WE CONVERT THE TRANSPORT SECTOR TO RENEWABLE ENERGY AND IMPROVE THE SECTOR'S INTERPLAY

  8. EMC analysis of static converters by the extraction of a complete equivalent circuit via a dedicated PEEC method

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    EMC analysis of static converters by the extraction of a complete equivalent circuit via. By coupling these two methods, an equivalent circuit with lumped elements is obtained. Consequently, EMC capacitance effects, is rapidly limited to analyze the EM interactions between subsystems or to draw up EMC

  9. On sliding mode and adaptive observers design for multicell converter M. GHANES, F. BEJARANO and J.P. BARBOT

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    of the semiconductor of power components and a new systems of energy conversion. Many of those systems present a hybrid to realize the input converter which supplies their "T13" locomotives in power. Three-phase inverters called by the robustness test with respect to resistance load variation. I. INTRODUCTION The power electronics [5] are well

  10. Abstract--An improvement to the precision of losses calculation in static converters used in a hybrid renewable

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    rates. In this article, a new approach to estimate the energy losses in the power electronics converters losses evaluation is demonstrated. Index Terms--power conversion losses, power generation, solar energy-state maximal current (A) M Inverter modulation index (-) Inverter load angle (rad) pdc/ac Inverter conduction

  11. can significantly improve the performance of colour-conversion In addition to applications as efficient colour converters, nano-

    E-Print Network [OSTI]

    Pierrehumbert, Raymond

    as efficient colour converters, nano- crystals have been considered promising building blocks for colour in the regime of electrical injection by combining nano- crystals with an electrically driven InGaN quantum well of high-efficiency, electrically driven, hybrid nano- crystal/quantum-well devices. A Received 9 February

  12. The Use of Power Sums to Solve the Harmonic Elimination Equations for Multilevel Converters EPE Journal Vol. 15 no

    E-Print Network [OSTI]

    Tolbert, Leon M.

    sources (solar cells, fuel cells, the rectified output of wind turbines) to an existing ac power grid of solar cells are dc voltages, and if this energy is to be fed to into an ac power grid, a powerThe Use of Power Sums to Solve the Harmonic Elimination Equations for Multilevel Converters EPE

  13. Creating systems that effectively convert energy, such as efficient solar cells and electrochemical batteries, has been a

    E-Print Network [OSTI]

    Reisslein, Martin

    SEMTE abstract Creating systems that effectively convert energy, such as efficient solar cells stimuli, the solar energy from sunlight, and the mechanical motion is commonplace, indeed fundamental and electrochemical batteries, has been a longstanding scientific pursuit, especially given the global energy

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

    E-Print Network [OSTI]

    Tolbert, Leon M.

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

  15. A high-speed, low-power analog-to-digital converter in fully depleted silicon-on-insulator technology

    E-Print Network [OSTI]

    Lundberg, Kent Howard

    2002-01-01T23:59:59.000Z

    This thesis demonstrates a one-volt, high-speed, ultra-low-power, six-bit flash analog-to-digital converter fabricated in a fully depleted silicon-on-insulator CMOS technology. Silicon-on-insulator CMOS technology provides ...

  16. Thermodynamic and kinetic studies of a catalytic process to convert glycerol into solketal as an oxygenated fuel additive

    E-Print Network [OSTI]

    Qin, Wensheng

    biodiesel production via transesterfication reactions. The biodiesel production generates approximately 10 exchange resin Kinetics a b s t r a c t Glycerol is a byproduct of biodiesel industry and can be converted with petroleum-based transporta- tion fuels, the interest in producing bio-fuels (bio-ethanol and biodiesel) has

  17. Fluid bed gasification – Plasma converter process generating energy from solid waste: Experimental assessment of sulphur species

    SciTech Connect (OSTI)

    Morrin, Shane, E-mail: shane.morrin@ucl.ac.uk [Department of Chemical Engineering, University College London, London WC1E 7JE (United Kingdom); Advanced Plasma Power, Swindon, Wiltshire SN3 4DE (United Kingdom); Lettieri, Paola, E-mail: p.lettieri@ucl.ac.uk [Department of Chemical Engineering, University College London, London WC1E 7JE (United Kingdom); Chapman, Chris, E-mail: chris.chapman@app-uk.com [Advanced Plasma Power, Swindon, Wiltshire SN3 4DE (United Kingdom); Taylor, Richard, E-mail: richard.taylor@app-uk.com [Advanced Plasma Power, Swindon, Wiltshire SN3 4DE (United Kingdom)

    2014-01-15T23:59:59.000Z

    Highlights: • We investigate gaseous sulphur species whilst gasifying sulphur-enriched wood pellets. • Experiments performed using a two stage fluid bed gasifier – plasma converter process. • Notable SO{sub 2} and relatively low COS levels were identified. • Oxygen-rich regions of the bed are believed to facilitate SO{sub 2}, with a delayed release. • Gas phase reducing regions above the bed would facilitate more prompt COS generation. - Abstract: Often perceived as a Cinderella material, there is growing appreciation for solid waste as a renewable content thermal process feed. Nonetheless, research on solid waste gasification and sulphur mechanisms in particular is lacking. This paper presents results from two related experiments on a novel two stage gasification process, at demonstration scale, using a sulphur-enriched wood pellet feed. Notable SO{sub 2} and relatively low COS levels (before gas cleaning) were interesting features of the trials, and not normally expected under reducing gasification conditions. Analysis suggests that localised oxygen rich regions within the fluid bed played a role in SO{sub 2}’s generation. The response of COS to sulphur in the feed was quite prompt, whereas SO{sub 2} was more delayed. It is proposed that the bed material sequestered sulphur from the feed, later aiding SO{sub 2} generation. The more reducing gas phase regions above the bed would have facilitated COS – hence its faster response. These results provide a useful insight, with further analysis on a suite of performed experiments underway, along with thermodynamic modelling.

  18. Guide for Identifying and Converting High-Potential Petroleum Brownfield Sites to Alternative Fuel Stations

    SciTech Connect (OSTI)

    Johnson, C.; Hettinger, D.; Mosey, G.

    2011-05-01T23:59:59.000Z

    Former gasoline stations that are now classified as brownfields can be good sites to sell alternative fuels because they are in locations that are convenient to vehicles and they may be seeking a new source of income. However, their success as alternative fueling stations is highly dependent on location-specific criteria. First, this report outlines what these criteria are, how to prioritize them, and then applies that assessment framework to five of the most popular alternative fuels--electricity, natural gas, hydrogen, ethanol, and biodiesel. The second part of this report delves into the criteria and tools used to assess an alternative fuel retail site at the local level. It does this through two case studies of converting former gasoline stations in the Seattle-Eugene area into electric charge stations. The third part of this report addresses steps to be taken after the specific site has been selected. This includes choosing and installing the recharging equipment, which includes steps to take in the permitting process and key players to include.

  19. Redesign of the H-Bridge Switch Plate of the SNS High Voltage Converter Modulator

    SciTech Connect (OSTI)

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

    2009-05-07T23:59:59.000Z

    The 1-MW High Voltage Converter Modulators [1] have operated in excess of 250,000 hours at the Spallation Neutron Source. Increased demands on the accelerator performance require increased modulator reliability. An effort is underway at SLAC National Accelerator Laboratory to redesign the modulator H-bridge switch plate with the goals of increasing reliability and performance [2]. The major difference between the SLAC design and the existing design is the use of press-pack IGBTs. Compared to other packaging options, these IGBTs have been shown to have increased performance in pulsed-power applications, have increased cooling capability, and do not fragment and disassemble during a fault event. An overview of the SLAC switch plate redesign is presented. Design steps including electrical modeling of the modulator and H-bridge, development of an integrated IGBT clamping mechanism, and fault tests are discussed. Experimental results will be presented comparing electrical performance of the SLAC switch plate to the existing switchplate under normal and fault conditions.

  20. Tri-county pre-commercial analysis of converting wastes to marketable products

    SciTech Connect (OSTI)

    Frolich, M. [Integrated Resource Development, Gardnerville, NV (United States); Munk, G. [Nevada Bio-Serv, Lovelock, NV (United States); McArthur, K. [Univ. of Nevada, Reno, NV (United States)] [and others

    1996-12-31T23:59:59.000Z

    Open field burning of harvest residues is an effective, low cost method of controlling diseases, insects and weeds in many agricultural operations. Restrictions have been imposed against this practice in several areas and these restrictions are expected to increase in the near future. The agricultural community in the Tri-County area of Nevada recognized that eventually burning would be an unacceptable practice of disposal. A biomass inventory was jointly funded by the area seed producers and Western Regional Biomass Energy Program that revealed a sufficient biomass resource to justify further work to answer the question: Can economic alternative methods of disposal be developed either through export of biomass or through conversion technologies in the local area? Technically the answer is yes. Several methods are available, either singly or in combination, capable of converting the difficult residues into energy or commodity products. Economically, the answer is not clear. There are many assumptions made in the financial analyses reported by the process developers that combine with a lack of concrete markets resulting in the conclusion that economic viability cannot be attained at the present time.

  1. Efficient ternary sources of working-body vapors for thermionic converters

    SciTech Connect (OSTI)

    Kalandarishvili, A.G.; Kashiya, V.G.

    1994-11-01T23:59:59.000Z

    The results of experiments to determine the energy characteristics of a cylindrical thermionic converter (TC) are presented. The TC investigated had ternary working-body vapor sources based on multicomponent cesium systems with either bismuth oxide, vanadium oxide, or tungsten oxide additions. Sorption characteristics of the systems were first determined, and then the ternary source was operated as part of the TC. The kinetics of the interaction of cesium vapor with the oxides was studied gravimetrically at various collector temperatures. The cesium TC electrical power output was increased 40 to 60% with a Cs{sub 12}Bi{sub 2}O{sub 3} ternary source in the arc mode. A Cs{sub 3}V{sub 2}O{sub 5} system increased TC output power from 20 to 40%, depending on emitter temperature. For the two Cs{sub x}WO{sub 3} sources examined, power increased almost 50%. The ternary sources examined also extended the working temperature range of the TC. 18 refs., 5 figs.

  2. Thermally induced evolution of morphology on ceramic surfaces in a thermionic converter

    SciTech Connect (OSTI)

    Zavadil, Kevin R.; Olson, David L.; Klinkov, Alexander E. [Sandia National Laboratories P.O. Box 5800 Albuquerque, New Mexico 87185-0342 (United States); Team Specialty Services 901 University Blvd. SE Albuquerque, New Mexico 87106-4439 (United States); JS INTERTEK 123182 Moscow Kurchatov Sq. 1 (Russian Federation)

    1997-01-10T23:59:59.000Z

    The morphology of alumina and scandia ceramics exposed to controlled vacuum and diffusion modes in a thermionic converter has been studied. Evidence for vaporization at a temperature of 1770 K is manifest in the resulting surface morphologies of both ceramics, consistent with reported sample mass loss. Alumina shows intergranular relief with the formation of terrace-step structure on the grain surfaces. Terrace formation is not directly observed on scandia, however the development of vertical structure and maintenance of voids indicates that vaporization is initiated by structure at the grain edges. Extensive Sc{sub 2}O{sub 3} re-deposition occurs on the scandia surface, possibly mediated by the presence of molybdenum and tungsten. Evidence exists for refractory metal secondary phase formation in this deposit in the form of Sc{sub 6}MO{sub 12} (M=W or Mo). Alumina also shows evidence for materials' interactions in the form of tantalum assisted vaporization which significantly alters the terrace structure.

  3. Thermally induced evolution of morphology on ceramic surfaces in a thermionic converter

    SciTech Connect (OSTI)

    Zavadil, K.R. [Sandia National Labs., Albuquerque, NM (United States); Olson, D.L. [Team Specialty Services, Albuquerque, NM (United States); Klinkov, A.E. [JS Intertek, Kurchatov (Russian Federation)

    1996-12-01T23:59:59.000Z

    The morphology of alumina and scandia ceramics exposed to controlled vacuum and diffusion modes in a thermionic converter has been studied. Evidence for vaporization at a temperature of 1,770 K is manifest in the resulting surface morphologies of both ceramics, consistent with reported sample mass loss. Alumina shows intergranular relief with the formation of terrace--step structure on the grain surfaces. Terrace formation is not directly observed on scandia, however the development of vertical structure and maintenance of voids indicates that vaporization is initiated by structure at the grain edges. Extensive Sc{sub 2}O{sub 3} re-deposition occurs on the scandia surface, possibly mediated by the presence of molybdenum and tungsten. Evidence exists for refractory metal secondary phase formation in this deposit in the form of Sc{sub 6}MO{sub 12} (M = W or Mo). Alumina also shows evidence for materials` interactions in the form of tantalum assisted vaporization which significantly alters the terrace structure.

  4. The effect of photoionization as an auxiliary discharge on characteristics of thermionic energy converter

    SciTech Connect (OSTI)

    Furukawa, H.; Kando, M. [Shizuoka Univ., Hamamatsu (Japan); Yamada, J. [Aich Institute of Technology, Toyota (Japan)

    1995-12-31T23:59:59.000Z

    The cesium filled thermionic energy converters (TEC) operated by the ignited mode have been expected as novel electric power generators, suitable for the space power systems and such terrestrial uses as cogeneration devices. They have the advantage free from the maintenance because of the device without any moving parts. However, the gaps of the electrodes are usually kept less than 1 mm to suppress the negative space potential in the space between the electrodes. Furthermore, for the ignited mode operation, the emitter should be heated up to the temperature higher than 1700 K. Such a restriction and the operating condition should be relaxed to make TEC spread by manufacturing at a moderate price. In the present work, the effect of an auxiliary discharge due to the photoionization has been examined by using TEC operated by the unignited mode with a longer electrode gap, compared with conventional one. It is clarified that the space charge neutrality in the space between both electrodes is drastically improved by the irradiation of Xenon lamp in the case of the emitter temperature lower than 1100 K and that the output current increases by a few times, compared with one without irradiation. This is caused by the photoionized plasma whose density is nearly 10{sup 9} cm{sup -3}.

  5. Characterization of sputter deposited thin film scandate cathodes for miniaturized thermionic converter applications

    SciTech Connect (OSTI)

    Zavadil, K.R.; Ruffner, J.H.; King, D.B. [Sandia National Laboratories, Materials Processing Sciences Center, Albuquerque, New Mexico 87185-0340 (United States)

    1999-01-01T23:59:59.000Z

    We have successfully developed a method for fabricating scandate-based thermionic emitters in thin film form. The primary goal of our effort is to develop thin film emitters that exhibit low work function, high intrinsic electron emissivity, minimum thermal activation properties and that can be readily incorporated into a microgap converter. Our approach has been to incorporate BaSrO into a Sc{sub 2}O{sub 3} matrix using rf sputtering to produce thin films. Diode testing has shown the resulting films to be electron emissive at temperatures as low as 900 K with current densities of 0.1 mA{center_dot}cm{sup {minus}2} at 1100 K and saturation voltages. We calculate an approximate maximum work function of 1.8 eV and an apparent emission constant (Richardson{close_quote}s constant, A{sup {asterisk}}) of 36 mA{center_dot}cm{sup {minus}2}{center_dot}K{sup {minus}2}. Film compositional and structural analysis shows that a significant surface and subsurface alkaline earth hydroxide phase can form and probably explains the limited utilization and stability of Ba and its surface complexes. The flexibility inherent in sputter deposition suggests alternate strategies for eliminating undesirable phases and optimizing thin film emitter properties. {copyright} {ital 1999 American Institute of Physics.}

  6. Characterization of Sputter Deposited Thin Film Scandate Cathodes for Miniaturized Thermionic Converter Applications

    SciTech Connect (OSTI)

    King, D.B.; Ruffner, J.H.; Zavadil, K.R.

    1998-12-14T23:59:59.000Z

    We have successfully developed a method for fabricating scandate-based thermionic emitters in thin film form. The primary goal of our effort is to develop thin film emitters that exhibit low work fimction, high intrinsic electron emissivity, minimum thermal activation properties and that can be readily incorporated into a microgap converter. Our approach has been to incorporate BaSrO into a SqOq matrix using rf sputtering to produce thin films. Diode testing has shown the resulting films to be electron emissive at temperatures as low as 900 K with current densities of 0.1 mA.cm-2 at 1100 K and saturation voltages. We calculate an approximate maximum work function of 1.8 eV and an apparent emission constant (Richardson's constant, A*) of 36 mA.cm-2.K-2. Film compositional and structural analysis shows that a significant surface and subsurface alkaline earth hydroxide phase can form and probably explains the limited utilization and stability of Ba and its surface complexes. The flexibility inherent in sputter deposition suggests alternate strategies for eliminating undesirable phases and optimizing thin film emitter properties.

  7. Thermally induced evolution of morphology on ceramic surfaces in a thermionic converter

    SciTech Connect (OSTI)

    Zavadil, K.R. [Sandia National Laboratories P.O. Box 5800 Albuquerque, New Mexico87185-0342 (United States); Olson, D.L. [Team Specialty Services 901 University Blvd. SE Albuquerque, New Mexico87106-4439 (United States); Klinkov, A.E. [JS INTERTEK 123182Moscow Kurchatov Sq. 1 (Russian Federation)

    1997-01-01T23:59:59.000Z

    The morphology of alumina and scandia ceramics exposed to controlled vacuum and diffusion modes in a thermionic converter has been studied. Evidence for vaporization at a temperature of 1770 K is manifest in the resulting surface morphologies of both ceramics, consistent with reported sample mass loss. Alumina shows intergranular relief with the formation of terrace-step structure on the grain surfaces. Terrace formation is not directly observed on scandia, however the development of vertical structure and maintenance of voids indicates that vaporization is initiated by structure at the grain edges. Extensive Sc{sub 2}O{sub 3} re-deposition occurs on the scandia surface, possibly mediated by the presence of molybdenum and tungsten. Evidence exists for refractory metal secondary phase formation in this deposit in the form of Sc{sub 6}MO{sub 12} (M=W or Mo). Alumina also shows evidence for materials{close_quote} interactions in the form of tantalum assisted vaporization which significantly alters the terrace structure. {copyright} {ital 1997 American Institute of Physics.}

  8. An Expression of Cultural Change: Invisible Converts to Protestantism Among Highland Guatemala Mayas

    E-Print Network [OSTI]

    Goldin, Liliana R.; Metz, Brent

    1991-01-01T23:59:59.000Z

    s t an t , a n d the r e m a i n i n g 87 per cent Ca tho l ic . Of the p resen t gene ra t ion ' s g r a n d p a r e n t s , on ly a b o u t 3 p e r cen t were Pro tes tan t . Th i s r ecen t and r ap id ra te of c o n v e r s i o n is associa ted w i t h a...AN EXPRESSION OF CULTURAL CHANGE: INVISIBLE CONVERTS TO PROTESTANTISM AMONG HIGHLAND GUATEMALA MAYAS Li l i ana R . G o l d i n a n d B r e n t M e t z State U n i v e r s i t y of N e w Y o r k , A l b a n y T h e process of re l ig ious...

  9. Floating atomic central heating-and-power plant converted from a strategic submarine

    SciTech Connect (OSTI)

    Bilashenko, V.P.; Gorigledzhan, E.A.; Slonimsky, V.J. [Military Regiment Nl., Moscow (Russian Federation)

    1993-12-31T23:59:59.000Z

    In accordance with {open_quotes}The Treaty on the Reduction of Strategic Offensive Arms{close_quotes} signed in July 1991, the operations envisages by {open_quotes}The Procedures for elimination of SSBN`s Launchers{close_quotes} should be accomplished at submarines of the second generation both by eliminating missile compartments together with launchers and by removal of launchers only from missile compartments. THe number of such ships could reach 30 units as has been forecasted for the year of 1998 inclusive. With regard to the fact that the remaining operation life of the main power plant equipment of a nuclear submarine decommissioned in accordance with the Treaty is about 50 per cent, potentially there is a possibility to convert them into floating atomic central heating-and-power plants. The latter variant envisaged in the {open_quotes}Procedures...{close_quotes} is preferable for developing a floating plant based on ships decommissioned from the Navy, since it permits to remove launchers without cutting and subsequent connection of main cables, pipelines and systems which provide the control of the main power plant, nuclear safety, radiological safety, damage control and fire safety of the floating plant. A submarine could be delivered for refitting into a floating plant only after accomplishing the works envisaged by the {open_quotes}Procedures...{close_quotes}.

  10. Monitoring of Total Type II Pyrethroid Pesticides in Citrus Oils and Water by Converting to a Common Product 3-Phenoxybenzoic Acid

    E-Print Network [OSTI]

    Hammock, Bruce D.

    Monitoring of Total Type II Pyrethroid Pesticides in Citrus Oils and Water by Converting to a Common Product 3-Phenoxybenzoic Acid Mark R. McCoy, Zheng Yang, Xun Fu,§ Ki Chang Ahn, Shirley J. Gee an alternative method that converts the type II pyrethroids to a common chemical product, 3-phenoxybenzoic acid

  11. iREED 2008 Renewable Energies and Eco-Design in Electrical Engineering, 10-11 December 2008 ECO-DESIGN OF ELECTRO-MECHANICAL ENERGY CONVERTERS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    iREED 2008 Renewable Energies and Eco-Design in Electrical Engineering, 10-11 December 2008 ECO-DESIGN OF ELECTRO-MECHANICAL ENERGY CONVERTERS: THE CASE OF THE THREE-PHASE SQUIRREL-CAGE INDUCTION MACHINE V-design problematic on the single criterion of energy for electro-mechanical energy converters through the model

  12. A thermionic energy converter with a molybdenum-alumina cermet emitter

    SciTech Connect (OSTI)

    Gubbels, G.H.M.; Wolff, L.R.; Metselaar, R. (Centre for Technical Ceramics, Eindhoven University of Technology, P. O. Box 513, 5600 MB Eindhoven, The Netherlands (NL))

    1990-12-01T23:59:59.000Z

    A study is made of the properties of cermets as electrode materials for thermionic energy converters. For thermodynamic reasons it is expected that all cermets composed of pure Mo and refractory oxides have the same bare work function. From data on the work function of Mo in an oxygen atmosphere this bare work function is estimated to be {Phi}=4.9 eV (at {ital T}=1400 {degree}C). Experimentally, the bare work function of Al{sub 2}O{sub 3}-Mo cermets was found to be {Phi}=4.5 eV, independent of the relative amounts of Al{sub 2}O{sub 3} and Mo. The cesiated work function of the Al{sub 2}O{sub 3}-Mo cermets was found to be 0.15 eV lower than the cesiated work function of pure Mo. The bare work function of Mo{sub 3}Al was found to be {Phi}=4.0 eV. The cesiated work function of Mo{sub 3}Al at collector temperature conditions was 0.3 eV lower than the cesiated work function of pure Mo. The electrical power density of a diode with an Al{sub 2}O{sub 3}-Mo cermet emitter was 0.4 W/cm{sup 2} at 1300 {degree}C. The barrier index at this temperature was 2.36 V. The high barrier index is attributed to a high plasma voltage drop {ital V}{sub {ital d}}=0.91 V.

  13. Monolithic, multi-bandgap, tandem, ultra-thin, strain-counterbalanced, photovoltaic energy converters with optimal subcell bandgaps

    DOE Patents [OSTI]

    Wanlass, Mark W. (Golden, CO); Mascarenhas, Angelo (Lakewood, CO)

    2012-05-08T23:59:59.000Z

    Modeling a monolithic, multi-bandgap, tandem, solar photovoltaic converter or thermophotovoltaic converter by constraining the bandgap value for the bottom subcell to no less than a particular value produces an optimum combination of subcell bandgaps that provide theoretical energy conversion efficiencies nearly as good as unconstrained maximum theoretical conversion efficiency models, but which are more conducive to actual fabrication to achieve such conversion efficiencies than unconstrained model optimum bandgap combinations. Achieving such constrained or unconstrained optimum bandgap combinations includes growth of a graded layer transition from larger lattice constant on the parent substrate to a smaller lattice constant to accommodate higher bandgap upper subcells and at least one graded layer that transitions back to a larger lattice constant to accommodate lower bandgap lower subcells and to counter-strain the epistructure to mitigate epistructure bowing.

  14. A Self-Aware Processor SoC using Energy Monitors Integrated into Power Converters for Self-Adaptation

    E-Print Network [OSTI]

    Devadas, Srinivas

    , Jason E. Miller1 , Henry C. Hoffmann3 , Srini Devadas1 and Anantha P. Chandraksan1 1 Massachusetts-efficiency [1][2]. However, power models cannot fully represent the actual profile of a complex processor system of the system is provided by two on-chip DC/DC converters that deliver variable load voltages from 0.6V to 1.8V

  15. Thermal conductivity of the electrode gap of a thermionic converter, filled with inert gases, at low pressures

    SciTech Connect (OSTI)

    Modin, V.A.; Nikolaev, Y.V.

    1985-11-01T23:59:59.000Z

    Experimental data is presented on the thermal conductivity of the electrode gap of a thermionic converter filled with He, Ar, and Xe in the pressure range 40--550 Pa. The need to account for the coefficients of thermal accommodation of the emitter-inert-gas-collector system in this range is shown. The accommodation coefficients for different temperature regimes are measured and expressions are obtained to calculate the heat flux transported by the inert gases in the electrode gap.

  16. Design and performance of radioisotope space power systems based on OSC multitube AMTEC converter designs

    SciTech Connect (OSTI)

    Schock, A.; Noravian, H.; Or, C. [Orbital Sciences Corp., Germantown, MD (United States)

    1997-12-31T23:59:59.000Z

    This paper extends the analytical procedure described in another paper in these proceedings to analyze a variety of compact and light-weight OSC-designed radioisotope-heated generators. Those generators employed General Purpose Heat Source (GPHS) modules and a converter containing sixteen AMTEC cells of OSC`s revised five-tube design with enhanced cell wall reflectivity described in a companion paper in these proceedings. OSC found that the performance of the generator is primarily a function of the thermal insulation between the outside of the generator`s 16 cells and the inside of its wall. After examining a variety of insulation options, it was found that the generator`s performance is optimized by employing a hybrid insulation system, in which the space between the cells is filled with fibrous Min-K insulation, and the generator walls are lined with tapered (i.e., graded-length) multifoil insulation. The OSC design results in a very compact generator, with eight AMTEC cells on each end of the heat source stack. The choice of the five-tube cells makes it possible to expand the BASE tube diameter without increasing the cell diameter. This is important because the eight cells mate well with the stacked GPHS modules. The OSC generator design includes a compliant heat source support and preload arrangement, to hold the heat source modules together during launch, and to maintain thermal contact conductance at the generator`s interfaces despite creep relaxation of its housing. The BOM and EOM (up to 15 years) performances of the revised generators were analyzed for two and three GPHS modules, both for fresh fuel and for aged fuel left over from a spare RTG (Radioisotope Thermoelectric Generator) fueled in 1982. The resulting power outputs were compared with JPL`s latest EOM power demand goals for the Pluto Express and Europa Orbiter missions, and with the generic goals of DOE`s Advanced Radioisotope Power System (ARPS) study. The OSC AMTEC designs yielded system efficiencies three to four times as high as present-generation RTGs.

  17. A 96-channel FPGA-based time-to-digital converter

    SciTech Connect (OSTI)

    Bogdan, Mircea; Frisch, Henry; Heintz, Mary; Paramonov, Alexander; Sanders, Harold [Chicago U., EFI; Chappa, Steve; DeMaat, Robert; Klein, Rod; Miao, Ting; Phillips, Thomas J [Duke U.; Wilson, Peter [Fermilab

    2005-02-01T23:59:59.000Z

    We describe an FPGA-based, 96-channel, time-to-digital converter (TDC) intended for use with the Central Outer Tracker (COT) [1] in the CDF Experiment [2] at the Fermilab Tevatron. The COT system is digitized and read out by 315 TDC cards, each serving 96 wires of the chamber. The TDC is physically configured as a 9U VME card. The functionality is almost entirely programmed in firmware in two Altera Stratix FPGA’s. The special capabilities of this device are the availability of 840 MHz LVDS inputs, multiple phase-locked clock modules, and abundant memory. The TDC system operates with an input resolution of 1.2 ns, a minimum input pulse width of 4.8 ns and a minimum separation of 4.8 ns between pulses. Each input can accept up to 7 hits per collision. The time-to-digital conversion is done by first sampling each of the 96 inputs in 1.2-ns bins and filling a circular memory; the memory addresses of logical transitions (edges) in the input data are then translated into the time of arrival and width of the COT pulses. Memory pipelines with a depth of 5.5 ?s allow deadtime-less operation in the first-level trigger; the data are multiple-buffered to diminish deadtime in the second-level trigger. The complete process of edge-detection and filling of buffers for readout takes 12 ?s. The TDC VME interface allows a 64-bit Chain Block Transfer of multiple boards in a crate with transfer-rates up to 47 Mbytes/sec. The TDC also contains a separately-programmed data path that produces prompt trigger data every Tevatron crossing. The trigger bits are clocked onto the P3 VME backplane connector with a 22-ns clock for transmission to the trigger. The full TDC design and multi-card test results are described. The physical simplicity ensures low-maintenance; the functionality being in firmware allows reprogramming for other applications.

  18. A DISTENSIBLETUBE WAVE ENERGY CONVERTER WITH A DISTRIBUTED POWERTAKEOFF R.C.T.Rainey, Atkins Ltd., Woodcote Grove, Epsom KT18 5BW, U.K. rod.rainey@atkinsglobal.com

    E-Print Network [OSTI]

    1 A DISTENSIBLETUBE WAVE ENERGY CONVERTER WITH A DISTRIBUTED POWERTAKEOFF R.C.T.Rainey, Atkins A distensibletube Wave Energy Converter (WEC) operates by converting the wave energy into "bulge waves interaction then occurs, and large bulge waves are generated, concentrating the wave energy

  19. Synthetic Metagenomics: Converting digital information back to Biology (2013 DOE JGI Genomics of Energy and Environment 8th Annual User Meeting)

    SciTech Connect (OSTI)

    Deutsch, Sam [DOE Joint Genome Institute

    2013-03-01T23:59:59.000Z

    Sam Deutsch of the DOE JGI on "Synthetic Metagenomics: Converting digital information back to Biology" at the 8th Annual Genomics of Energy & Environment Meeting in Walnut Creek, Calif.

  20. Low-Variation 1 MHz Clock Generator,High Sensitivity Linear Voltage-to-Frequency Converter,and High-PSR Bias Circuit for NTSC SYNC Separation.

    E-Print Network [OSTI]

    Lee, Tzung-Je

    2004-01-01T23:59:59.000Z

    ??This thesis includes three topics. The first topic is a low-variation 1 MHz clock generator. The second one is a high sensitivity linear voltage-to-frequency converter.… (more)