SPACE SOLAR POWER SANDWICH MODULE TESTING AND PERFORMANCE CHARACTERIZATION

摘要

The prospect of effectively limitless, continuous electricity from orbiting satellites for use on earth has captured people's interest for many years. The approach entails collection of solar energy in space and its wireless transmission to the earth. This potentially gives the benefit of provision of baseload power while avoiding the losses due to the dayight cycle and atmospheric effects that are associated with terrestrial solar power. Among recent implementations commonly proposed for Space Solar Power (SSP), the Modular Symmetrical Concentrator, SPS-ALPHA, and other modular concepts have received considerable attention. Each employs an array of modules for performing conversion of concentrated sunlight into microwaves or laser beams for transmission to earth. The research described herein includes efforts in the development, testing, and characterization of photovoltaic arrays, power electronics, microwave conversion electronics, and antennas for two types of 2.45 GHz microwave-based "sandwich" module prototypes. Tile and step sandwich module prototypes were designed, fabricated, and subjected to the challenging conditions inherent in the space environment, including vacuum, temperatures, and the solar concentration levels in which an array of modules might be required to operate. Results from module testing under various conditions are presented. Metrics of interest are explicated and results are discussed. For the tile sandwich module, an area-specific mass of 21.9 kg/m2 and mass-specific power of 4.5 W/kg at about one sun illumination were achieved. The total combined efficiency of the tile module was shown to be on the order of 9% for vacuum operation at 10~(-6) torr.