Solar Thermionic Generators for Space Power

Abstract

All solar space power systems are subject to the condition that the amount of solar energy available in space depends on the collector-sun distance, which generally differs among missions and which may change markedly during the course of any one mission. Thus the design problem exists of how to tailor the system so as to best use the available solar flux. Furthermore, particularly in the case of thermionic systems, it is difficult to change arbitrarily the size of the system. It is therefore of interest to find the system size which can best fit a variety of missions without need for alterations which increase cost and decrease reliability. An approach to handle this design problem is presented, and numerical examples are given based on the data obtained from tests on the hardware prototype of a solar thermionic generator.