The operating characteristics of homopolar generators and superconducting inductive energy storage syatems are summarized. A survey is made of possible prime power sources for space-based homopolar generators. Free-World state-ofthe–art electrical pulse power technology ia evaluated. An analysis is made of the possible uses of homopolar generators and superconducting inductive energy storage systems in power supplies for high-energy, space-based lasers. Overall system mass is of primary importance in the analysis. These types of power supplies are evaluated for possible application to Controlled Thermonuclear Reactor (CTR) experiments. .— INTRODUCTION Capacitive energy storage systems are employed in the power suppliee of pulsed lasers. However, aa lasers become larger (laser energies greater than 10 kJ perpulse), the cost and size of the required capacitive energy storage systems may be prohibitive, particularly for space-based laser applications. Investigations into alternative pulse power systems appear warranted at this time. The homopolar generator combined with a superconducting inductive energy storage system appears to be a power supply which overcomes the cost and mass disadvantages of capaci– tive energy storage. The report summarizes the results of a feasibility study of employing this type of power supply for high-energy, space-based laser applications. II. HOMOPOLAR GENERATORS A. Description The homopolar generator, the unipolar, or acyclic generator, is basically a dc machine which can develop large currents, up to 1.6 MA, at moderately low voltages, usually in the 50to 800-v range. A homopolar machine may be used as either a generator or a motor. A cutaway view of a typical homopolar generator is given in Fig. l.l Magnetic flux, produced by the two field coils, generates a voltage in the spinning rotor proportional to the rate at which the flux is cut. The voltage generated in the rotor causea a current to flow between the two current collectors. The homopolar generator derives its name from the fact that the flux is always cut in the same direction. Because the rotor has no windings, the homopolar generator is able to withstand much higher transient loadings than the conventional ac or dc generators. To facilitate the collection of the large dc currents in the machine, the entire rotor