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The conventional XRAM (MARX spelled backwards) current multiplier circuit is similar in concept to the better known MARX voltage multiplier circuit. In the MARX circuit, capacitors charged in parallel from a voltage source are switched to discharge in series producing an output voltage approximately equal to the sum of individual capacitor voltages. In the XRAM circuit, inductors energized in series from a current source (battery, homopolar generator, other) are switched to discharge in parallel, producing an output current which is the sum of the individual inductor currents. In high energy pulsed power systems these multiplier techniques simplify primary power design at the expense of more complex switching. The hybrid XRAM circuit described in this paper minimizes switching requirements while retaining the positive benefits of the conventional XRAM circuit. It also provides a smooth rising current waveform which is useful for EM and ET gun research. The tradeoff for these benefits is that, during switching, approximately 50% of total system energy is stored in a capacitor bank of simple design. In addition to simplified switching, the hybrid concept offers other advantages over either an all capacitive or all inductive system. As a laboratory power supply at 2-3 MA current and 10-20 MJ stored energy, it doubles energy which would be available from a capacitive system while offering the current 'stiffness' available from an inductive system. Less obvious but potentially of greater interest, the concept appears to scale to high energy (10's to 100's of MJ) for either a distributed energy or multi shot power supply. This paper outlines two XRAM circuit concepts, and discusses the distributed energy and multi-shot aspects of the hybrid concept. It also describes a more detailed study of a battery powered hybrid XRAM current doubler design being considered for use as a general purpose laboratory inductive energy supply, operating at up to 2.5 MA with as much as 10 MJ of electrical energy stored. The circuit described is modeled using known values from existing circuit components. Resulting waveforms are shown and benefits derived from the use of this circuit are compared to those from a conventional XRAM current doubler as well as from a direct, inductive store, system design.

The Electric Research Power Institute (EPRI) has launched the Discovery, Development and Delivery Recognition Awards to pay tribute to the individuals who have made significant contributions to the field of electric power research. EPRI Pres Richard Balzhiser presented the awards at a dinner in Palo Alto on Nov 9, 1991, stating that the new technological breakthroughs ushered in by this event could dramatically improve the services being offered by utility companies to the public.

The rising cost of oil and the environmental hazards posed by coal led authorities in the utility industry to reconsider their position regarding the use of natural gas in electric power generation. Various organizations, including the Electric Power Research Institute, are investing in extensive research and development programs to establish the guidelines needed for the safe and efficient operation of gas-powered electric plants and determine the the long term viability of this technology.

The technological progress of power frequency ac superconductor is remarkable and application studies are being carried out, targeting ac super-conducting (SC) machines for power systems. The introduction of SC machines into the power system, needs to display the merits of not only efficiency improvement but also power system performance and operation. A conceptual design for a coreless super-conducting transformer (SCT) is made, based on the above views and it's merits evaluated. A future possible power system employing coreless SCT's is presented, and consideration is given to the actual service in a future power system. Index Terms--Coreless superconducting transformer, exciting current, shunt reactor, fault current limiter, ac superconductor, low temperature electrical insulation, power system.

More than a year ago, the British army began testing boots made by Britain's Electric Shoe Company. These boots used the mechanical energy of walking to produce about 3 watts [...]

Several years ago, there was strong interest in finding alternatives to petroleum energy for the United States. Related congressional legislation includes the Energy Tax Act of 1978 and the Public Utility Regulatory Policies Act of 1978. State legislation toward such a goal also occurred. The legislative provisions are analyzed. Research has had conflicting findings. Viewed from a systemic perspective solar energy has been seen as economically viable only when peak-load pricing was used. For home owners, flat or declining block electricity pricing was preferable. A model is promulgated for comparing life cycle costs of various alternative home heating systems. Comparisons of resistance electric heat electric heat pump, active solar energy and a conventional petroleum burning furnace are made. Tables of related data are included. Capital and storage needs are analyzed.