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This paper examines the effort of solid state switching upon aerospace electric power conditioning equipment. During the past ten years, aerospace solid state switching concepts have undergone laboratory and flight test evaluations to establish the feasibility of the systems approach. This extension of the program to include power conditioning studies reveals several parameters affecting the design of power conditioning equipment and decsribes several new systems capabilities.

STOL aircraft electric power variable frequency generation and high voltage DC distribution with secondary square wave AC distribution

Unmanned soft lunar landing experiments by the United States are currently being planned by the National Aeronautics and Space Administration. All of these experiments will require some form of electrical power; and their success or failure will depend upon the development of a suitable, reliable electrical power generation system. The system utilized must be compact, lightweight and rugged. Certain requirements for such an experiment could be met by solar cell arrays. The reliability of solar cells has been well established; however, their usefulness for this mission is inherently limited. Experiments conducted during the lunar night require a large storage capacity, if solar energy is to be the spacecraft's only source of power. A radioisotope-fueled thermoelectric generator can fulfill all spacecraft power requirements continuously throughout the lunar day or night without special orientation. A radioisotope, such as Curium-242, may be used as the thermal energy source for a lunar experiment of short duration (90 to 120 days). Curium-242 does not occur in nature, but may be created by the neutron irradiation of Americium-241. This radioisotope requires very little radiation shielding to protect sensitive equipment, because of the low gamma flux associated with its decay. The rigors of the lunar "climate" produce an environment which present-day electronic equipment will not tolerate. By utilizing waste heat from the radioisotope generator, the electronics compartment temperature may be controlled within acceptable limits. All subsystems within the generator may be duplicated to improve its reliability.

AN ANALYSIS IS MADE OF THE POWER REQUIREMENTS OF AN ELECTRIC URBAN AND SUBURBAN VEHICLE HAVING PERFORMANCE STANDARDS BASED ON THE CALIFORNIA DRIVING CYCLE AND A RANGE OF 150 MILES WITH REGENERATIVE BRAKING. TO SATISFY THESE REQUIREMENTS, A HYBRID SYSTEM COMPRISING A LITHIUM/NICKEL-FLUORIDE NON-AQUEOUS BATTERY FOR TOTAL ENERGY REQUIREMENTS AND A BIPOLAR NICKEL/CADMIUM BOOSTER BATTERY FOR ACCELERATION AND HILL-CLIMBING IS PROPOSED. THE BATTERY SYSTEM IS DESCRIBED, AND SOME PERFORMANCE DATA ARE GIVEN. /AUTHOR/