Analysis and Experimental Verification of Space Grade Power Supply Performance under Thermo-Vacuum Environment

Space grade subsystems require judicious combination of design, analysis and testing to realize a flight worthy hardware. These subsystems operate in an environment considerably different from that in which they are built and after launch they are inaccessible to routine maintenance and repair. The thermal vacuum test is one of the most critical environmental tests and all the subsystem have to pass this test in order to maintain the high reliability. Finite element method approach is used for the thermal analysis of the power supply by considering the thermo vacuum boundary conditions for the study of behaviour of highly dissipating components and the temperature profile. This paper presents the design considerations for realizing a space grade Power supply from its thermal and vacuum performance perspective. Comparison is made between the results of the thermal analysis and actual test under vacuum conditions of Flight model. Also the result of the qualification model which is tested at higher temperature is discussed. Design margins are also established through actual testing in thermo vacuum chamber to achieve the onboard performance of the Power supply under vacuum in geo-stationary environment for a product life of 15 years.