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Power Supply Reliability Estimates for Experimental Fusion Facilities

Description: This paper presents the results of a task to analyze the operating experience data for large, pulsed power supplies used at the DIII-D tokamak. This activity supports the International Thermonuclear Experimental Reactor (ITER) project by giving fusion-specific reliability values for large power supplies that energize neutral beams and magnets. These failure rate data are necessary to perform system availability calculations and to make estimates of the frequency of safety-significant events (e.g., power supply arcs or fires) that might occur in other fusion facilities such as ITER. The analysis shows that the DIII-D data results compare well with the results of similar data analysis work that the Italian National Agency for New Technologies, Energy and the Environment (ENEA) has performed on the JET tokamak and compare fairly with data from two accelerators.
Date: November 1, 2006
Creator: Cadwallader, Lee; Pinna, Tonio & Petersen, Peter
Partner: UNT Libraries Government Documents Department

Construction and testing of the 2XIIB flat-topping power supply

Description: The construction details and test results of the 2XIIB flat-topping modules are described. Both practical design and construction considerations as well as fabrication techniques are discussed. Power for the main compression coils of the 2XIIB is derived by discharging a high-voltage capacitor bank and then crowbarring at the current peak to obtain L/R decay in the fields. To study plasma confinement under these quasi steady-state conditions, it is necessary to hold the compression-coil current constant for 10 ms. This is done by supplying only the I$sup 2$R losses of the system, using a low-voltage bank. The low- voltage bank consists of 48 modules each supplying 20,000 A at +-450 V to each compression coil for a total of 480,000 A. The low-voltage electrolytic bank is isolated from the high-voltage (20-kV) bank by silicon diodes, which also act as crowbars at the end of the 10-ms flat-topping or in the event that the electrolytic bank is not used. The 10-ms pulse is obtained by sequentially discharging ten electrolytic ''drawers,'' each supplying a 1-ms pulse to each of the 48 modules. Each ''drawer'' consists of 24 1500-$mu$f electrolytic capacitors controlled by a thyristor and isolated from each other by rectifier diodes. Inductors are included as part of each drawer to limit the di/dt of the thyristor during the commutation process. (auth)
Date: November 1, 1975
Creator: Refigato, L.L. & Smith, B.H.
Partner: UNT Libraries Government Documents Department

Saturable reactor-controlled power supply system for TCT/TFTR neutral beam sources

Description: Each neutral beam source requires one major power supply, the acceleration supply, and four auxiliary power supplies. The power supplies are designed to permit independent interruption of current to any source and crowbarring within 20 $mu$sec, in the event of a source spark, while not disturbing the normal pulsing of all other adjacent sources. The sources are described. (MOW)
Date: November 1, 1975
Creator: Baker, W. R.; Hopkins, D. B.; Dexter, W. L.; Kuenning, R. W. & Smith, B. J.
Partner: UNT Libraries Government Documents Department

TAGS-85/2N RTG Power for Viking Lander Capsule

Description: Results of studies performed by Isotopes, Inc., Nuclear Systems Division, to optimize and baseline a TAGS-85/2N RTG for the Viking Lander Capsule prime electrical power source are presented. These studies generally encompassed identifying the Viking RTG mission profile and design requirements, and establishing a baseline RTG design consistent with these requirements.
Date: August 1, 1969
Partner: UNT Libraries Government Documents Department

Power supplies for space systems quality assurance by Sandia Laboratories

Description: The Sandia Laboratories' participation in Quality Assurance programs for Radioisotopic Thermoelectric Generators which have been used in space systems over the past 10 years is summarized. Basic elements of this QA program are briefly described and recognition of assistance from other Sandia organizations is included. Descriptions of the various systems for which Sandia has had the QA responsibility are presented, including SNAP 19 (Nimbus, Pioneer, Viking), SNAP 27 (Apollo), Transit, Multi-Hundred Watt (LES 8/9 and MJS), and a new program, High-Performance Generator Mod 3. The outlook for Sandia participation in RTG programs for the next several years is noted.
Date: July 1, 1976
Creator: Hannigan, R. L. & Harnar, R. R.
Partner: UNT Libraries Government Documents Department

Photovoltaic markets: a review and assessment

Description: Available information on potential markets for photovoltaic power systems is reviewed. A set of key parameters which affect the rate of photovoltaic market penetration is used to develop a simple anaytical structure that characterizes potential markets. Completed studies on photovoltaic markets were reviewed to describe potential markets using this structure. Selected markets were then examined in greater detail in a market demand workshop attended by potential purchasers in these markets. Available information, while sufficient to provide a rudimentary indication of how markets might develop, does not allow the construction of any single market scenario in which a high level of confidence can be placed. Major uncertainties in the available information on photovoltaic markets are highlighted.
Date: June 1, 1979
Creator: Posner, D. M.
Partner: UNT Libraries Government Documents Department

Fault protection for neutral-beam injection systems

Description: This paper discusses the accelerating, or main supply for the Neutral Injection System on PLT and, in particular, provides evaluation of a system for protection against the possibility of an arc developing in the accel portion of the ion source gun. The design of a protection scheme utilizing a fast turn-on and turn-off ignitron crowbar is described and evaluated. This crowbar is used to provide backup protection for the ion source high power vacuum tube used as a voltage regulator and series switch. Ignitron crowbars are proposed for use as primary protection of the 150 KV ion source being developed for the Tokamak Fusion Test Reactor (TFTR) if a 150 KV switch tube is not readily available and inexpensive. (auth)
Date: December 1, 1975
Creator: Knauer, R. C.; Ashcroft, D. L.; Murray, J. G. & Newman, R. A.
Partner: UNT Libraries Government Documents Department

Nuclear powered satellite studies. Annual progress report, July 1, 1978-June 30, 1979

Description: Progress achieved during the period July 1, 1978 to June 30, 1979, on US DOE contract No. EY-76-S-02-4045.A002 is reported. Discussions of several pertinent aspects are included, e.g., schedule, personnel, technology developments, and plans. The reporting period represents the third year of activities of a project which is designed to provide continuing support in the area of nuclear space power technology. Important results have been obtained and communicated to the scientific community via publications and presentations. Project personnel have participated in point design efforts, a NASA Space Power Committee, and periodically provide support to Department of Energy activities as the need arises. The report is intended to summarize activities over the past year and provide a basis for continued project support by US DOE.
Date: June 1, 1979
Creator: Kaplan, M.H.
Partner: UNT Libraries Government Documents Department

Heat source component development program, October 1977--February 1978

Description: The General Purpose Heat Source (GPHS) is being developed by Los Alamos Scientific Laboratory (LASL) for the Department of Energy (DOE) Division of Nuclear Research and Application (DNRA). The first mission scheduled for the GPHS is the NASA Out-of-Ecliptic Flight in January, 1983. During the current reporting period (October--December, 1977, January--February, 1978), activities in this task were conducted as follows: (1) documentation of results of the reentry thermal, ablation, and thermal stress analyses of the conceptual designs; (2) identification and completion of modifications to the thermal and ablation models used to determine the performance response of the heat source modules during reentry; (3) initiation of modifications to the thermal stress model used to determine the performance response of heat source modules during reentry; (4) completion and documentation of the surface chemistry experiments; (5) initiation and completion of activities in support of LASL to define test plans for the trial design phase of the GPHS development program; (6) participation in the GPHS design review meeting held at DOE/Germantown, Maryland, December 19--20, 1977; and (7) initiation of the thermal analysis of Trial Design 1.1.
Date: March 1, 1978
Partner: UNT Libraries Government Documents Department

Analysis techniques used on field degraded photovoltaic modules

Description: Sandia National Laboratory`s PV System Components Department performs comprehensive failure analysis of photovoltaic modules after extended field exposure at various sites around the world. A full spectrum of analytical techniques are used to help identify the causes of degradation. The techniques are used to make solder fatigue life predictions for PV concentrator modules, identify cell damage or current mismatch, and measure the adhesive strength of the module encapsulant.
Date: September 1, 1995
Creator: Hund, T.D. & King, D.L.
Partner: UNT Libraries Government Documents Department

Flat-topping power supply for the 2XIIB containment magnet

Description: From 5th symposium on engineering problems of fusion research: Princeton, New Jersey, USA (6 Nov 1973). Power supplies are being developed to maintain a current constant at the peak value in containment magnet coils for a period of 20 msec. Each power supply consists of a bank of electrolytic capacitors which is divided into 20 sections. All sections are charged initially to the appropriate voltage and then discharged sequentially at 1 msec intervals until their energy is expended. The design considerations of these power supplies and the transmission and load systems are discussed. (auth)
Date: October 12, 1973
Creator: Smith, B. H.; Reginato, L. L.; Robinson, J. W. & Dexter, W. L.
Partner: UNT Libraries Government Documents Department

Artificial heart development program. Volume II. System support. Phase III summary report. Period covered: July 1, 1973--September 30, 1977

Description: Appendix A covers major activities of the Artificial Heart Development program that supported the design, fabrication, and test of the system demonstration units. Section A.1.0 provides a listing beyond that of the body of the report on the components needed for an implantation. It also presents glove box sterilization calibration results and results of an extensive mock circulation calibration. Section A.2.0 provides detail procedures for assembly, preparing for use, and the use of the system and major components. Section A.3.0 covers the component research and development activities undertaken to improve components of the existing system units and to prepare for a future prototype system. Section A.4.0 provides a listing of the top assembly drawings of the major systems variations fabricated and tested.
Date: January 1, 1977
Partner: UNT Libraries Government Documents Department

Artificial heart development program. Volume I. System development. Phase III summary report

Description: The report documents efforts and results in the development of the power system portions of a calf implantable model of nuclear-powered artificial heart. The primary objective in developing the implantable model was to solve the packaging problems for total system implantation. The power systems portion is physically that portion of the implantable model between the Pu-238 heat sources and the blood pump ventricles. The work performed had two parallel themes. The first of these was the development of an integrated implantable model for bench and animal experiments plus design effort on a more advanced model. The second was research and development on components of the system done in conjunction with the development of the implantable model and to provide technology for incorporation into advanced models plus support to implantations, at the University of Utah, of the systems blood pumping elements when driven by electric motor. The efforts and results of implantable model development are covered, mainly, in the text of the report. The research and development efforts and results are reported, primarily, in the appendices (Vol. 2).
Date: January 1, 1977
Partner: UNT Libraries Government Documents Department

Five-megajoule homopolar upgrade

Description: The five-megajoule homopolar generator (5-MJ HPG) designed and built in 1974 by the Center for Eelctromechanics at the University of Texas at Austin (CEM-UT) was the result of an engineering feasibility study that examined alternate means of pulsed energy storage for controlled thermonuclear fusion experiments. The machine proved very reliable and useful in a variety of applications, notably pulsed resistance welding, and was modified in 1978 to improve its flexibility and ease of maintenance. CEM-UT is now completing a major upgrading of this HPG to a hydraulically motored, 10-MJ, 47-V, 1.02-MA device capable of welding large-section, high-carbon railroad rail. This report considers the design and fabrication of the new rotor, shaft, brush mechanisms, field coil, making switch, busbar system, and control system, as well as the addition of the 31-MPa (4500 psi) hydraulic motoring system. Future applications of the 10-MJ HPG are also discussed.
Date: January 1, 1981
Creator: Bullion, T.M.; Zowarka, R.C.; Aanstoos, T.A.; Weldon, W.F.; Rylander, H.G. & Woodson, H.H.
Partner: UNT Libraries Government Documents Department

Heat source component development program. Report for period March 1978--June 1978. [General purpose heat source]

Description: The General Purpose Heat Source (GPHS) is a radioisotope heat source being developed by LASL. The first intended application for the GPHS is the Solar Polar mission scheduled for 1983. Battelle's support of LASL during the current reporting period is reported. The specific efforts include: (1) analysis of trial designs with emphasis on comparison of performances of trial designs 1 and 2 and their modifications; and (2) helium vent development with emphasis on fabrication and qualification testing of platinum and iridium nonselective vents. (TFD)
Date: July 1, 1978
Partner: UNT Libraries Government Documents Department

Final safety analysis report for the Galileo Mission: Volume 2: Summary

Description: The General Purpose Heat Source Radioisotope Thermoelectric Generator (GPHS-RTG) will be used as the prime source of electric power for the spacecraft on the Galileo mission. The use of radioactive material in these missions necessitates evaluations of the radiological risks that may be encountered by launch complex personnel and by the Earth's general population resulting from postulated malfunctions or failures occurring in the mission operations. The purpose of the Final Safety Analysis Report (FSAR) is to present the analyses and results of the latest evaluation of the nuclear safety potential of the GPHS-RTG as employed in the Galileo mission. This evaluation is an extension of earlier work that addressed the planned 1986 launch using the Space Shuttle Vehicle with the Centaur as the upper stage. This extended evaluation represents the launch by the Space Shuttle/IUS vehicle. The IUS stage has been selected as the vehicle to be used to boost the Galileo spacecraft into the Earth escape trajectory after the parking orbit is attained.
Date: December 15, 1988
Partner: UNT Libraries Government Documents Department

International photovoltaic products and manufacturers directory, 1995

Description: This international directory of more than 500 photovoltaic-related manufacturers is intended to guide potential users of photovoltaics to sources for systems and their components. Two indexes help the user to locate firms and materials. A glossary describes equipment and terminology commonly used in the photovoltaic industry.
Date: November 1, 1995
Creator: Shepperd, L.W. & Florida Solar Energy Center, Cocoa, FL (United States)]
Partner: UNT Libraries Government Documents Department

Reliability of Rechargeable Batteries in a Photovoltaic Power Supply System

Description: We investigate the reliability If a rechargeable battery acting as the energy storage component in a photovoltaic power supply system. A model system was constructed for this that includes the solar resource, the photovoltaic power supp Iy system, the rechargeable battery and a load. The solar resource and the system load are modeled as SI ochastic processes. The photovoltaic system and the rechargeable battery are modeled deterministically, imd an artificial neural network is incorporated into the model of the rechargeable battery to simulate dartage that occurs during deep discharge cycles. The equations governing system behavior are solved simultaneously in the Monte Carlo framework and a fwst passage problem is solved to assess system reliability.
Date: November 30, 1998
Creator: Barney, P.; Jungst, R.G., Ingersoll, D.; O'Gorman, C.; Paez, T.L. & Urbina, A.
Partner: UNT Libraries Government Documents Department

The New 1999 National Electrical Code Coupled with New Standards Clarify Requirements for Installations of Photovoltaic Systems in the U.S.

Description: The National Electrical Code@ (NEC@) focuses primarily on electrical system installation requirements in the U.S. The NEC addresses both fire and personnel safety. This paper will describe recent efforts of the PV industry in the U.S. and the resulting requirements in the 1999 National Electrical Code-- Article 690 --Solar Photovoltaic Systems. The Article 690 requirements spell out the PV-unique requirements for safe installations of PV systems in the U.S.A. This paper provides an overview of the most significant changes that appear in Article 690 of the 1999 edition of the NEC. The related and coordinated efforts of the other standards- making groups will also be briefly reviewed.
Date: January 8, 1999
Creator: Bower, W.
Partner: UNT Libraries Government Documents Department
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