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In the process of developing a high power inverter utilizing S.C.R.'s in high voltage D.C. bridges, it became apparent that the commutator circuit would determine the inverter size and weight. Therefore, we developed a single co mutator circuit that was capable of commutating multiple bridges. Using similar reasoning we felt that the commutator should be as conservative of power as possible. These...
The self-healing fuse is a very fast acting current overload protective device which opens and recloses in a few milliseconds. The fuse confines a mercury column in an insulated channel and returns the mercury to the channel after firing. Ratings 5 to 50 amperes at 600 peak volts are possible with a life of hundreds of cycles. Compared to conventional fuses, much less fault current energy fires the...
USAMERDCs development efforts have been directed toward compact and efficient power supplies in order to cut the weight and bulk of power conditioning equipment presently used. In this effort, weight reduction has been achieved at the cost of considerable equipment complexity and possible difficulties concerning field serviceability by semi-skilled personnel. This complexity is mainly due to the restrictions...
The design and testing of Transcalent Solid State Power Devices are described. In a Transcalent Device the active element is made an integral part of two heat pipes. Thus the mechanical and thermal barriers between the silicon and the heat rejection surfaces are eliminated. Discussed will be the operational characteristics of the Transcalent Devices and, briefly, the design and fabrication of a 400...
This work discusses the application of power conditioning to high speed ground transportation vehicles propelled by linear induction motors. The vehicle electric power and propulsion system and characteristics of selected vehicles currently under development by the u.S. Department of Transportation are discussed. A Brief review of the linear induction motor is presented. Several classes of power conditioners...
The objective of this investigation is to determine the best means of processing the power from remotely placed batteries or fuel cells to power sensors and communication devices having very light, steady state loads and much heavier short duration pulse loads. This paper discusses the requirements, interface characteristics, and problem areas associated with various approaches and illustrates the...
During the past ten years the Army has invested a sizable effort into new systems configurations and development programs to improve ground vehicle mobility. USAMERDC, Fort Belvoir, Virginia, has been particularly interested in an improved vehicle mobility for off-highway vehicles, amphibians and engineer equipment through electrical propulsion. Because electrical propulsion drive systems feature...
The results of a current NASA study program to develop arational basis for selection of power processing, distribution and control configurations for future aerospace vehicles including the Space Station, Space Shuttle, and high performance aircraft are presented. Within the constraints imposed by the characteristics of power generation subsystems and the load utilization equipment requirements, the...
The Aerospace and Electronic Systems Group is an organization, within the framework of the IEEE, of members with a similarity of professional interests. All members of the IEEE are eligible for membership in the Group, and will receive the TRANSACTIONS and NEWSLETTER of the group upon payment of the annual Group membership fee of $5.00. For information on joining write to the IEEE at the address below.
A P.W.M. power system unit is presented for a modular regulated bus concept. This power system is composed of 4 shunt sections and 2x20 AH,Ag-Cd batteries, with independent charger and discharger functions. All these regulators operate under P.W.M. control at 100 KHz sampling frequency and phase shifted synchronisation for minimising ripple and filtering. The sequence of the operation is the following,...
One of the earliest-developed and still widely-used dc to square-wave inverters is the Royeror Uchrin-Taylor configuration shown in Fig. 1. Although the circuit is composed of very few components, its proper operation depends on complex interactions of the transformer as it switches between its unsaturated and saturated regions, and the tow transistors as they switch between cut-off and saturation...
The transient and steady state performance of a group-triggered cycloconverter supplying a controlled slip induction motor is studied using an analog computer. System equations are derived from equivalent circuits for the cycloconverter, source, and motor networks. The induction motor is represented in terms of qdo components in a stationary reference frame. Computer results are compared with test...
The theme of the first technical session was methods of analysis as applied to a variety of electronic power processing systems. The seven papers, all of which could be classified as research papers, presented new concepts and ideas relating to the analysis, design and management, of power by electronic means and provided a theoretical basis upon which many of the circuits and systems presented in...
All papers published in this Conference Record are considered as "Publications of Record." An abstract of each paper will appear in the September 1972 issue of the IEEE Transactions on Aerospace and Electronic Systems, Volume AES 8 Number 5. The abstracts and the papers in this volume will be included in the 1972 Index to this publication. Each paper published in this Record was reviewed...
A new modulation technique has advanced the state of the art in pulsed high power short arc xenon flashlamps. The design of a 50 kW pulsed average power xenon arc lamp was predicated on the development of a push-pull type of modulator to enable heat to be equally extracted from both electrodes. Normally, arc lamps are pulsed from a dc source resulting in high anode temperatures and consequent deterioration...
The reFLEX principle is a new battery charging technique. This paper explains how it works, why it is superior to other battery charging methods and what effect various parameters have on its operation. It provides results of Government and commercial tests, evaluations and daily use. It reports on the present status of reFLEX charging with various types of batteries.
Protection of battery cells from overcharge and from over-discharge is an important criteria for the successful operation of battery cells over long lifetimes. Battery level charge control based on cell level parameters also improves battery operation. Circuitry to perform both of these functions has been developed by TRW Systems under contract with the Wright-Patterson Air Force Base Aero Propulsion...
The paper deals with the novel aspects of a newly developed transient voltage suppressor. Details of its operation, fabrication and characterization are given. Its performance is compared against the more familiar devices currently used for transient voltage protection including devices such as spark gaps, zeners and selenium suppressors. Application features are discussed briefly. Future development...