Solar Array Simulators for INSAT-2E/3B

Abstract

Considering that a spacecraft cannot be accessed after launch and it is subjected to harsh environmental conditions during launch such as shock, vibration, acoustics in addition to vacuum, large temperature variation during orbit; the design of various subsystems must take into account both the short and long term effects of this environment and ground testing must establish that the quality and reliability of the spacecraft is acceptable through out its long life mission. The integrated spacecraft testing must ensure that all various subsystems and their respective interfaces are performing satisfactorily and working in unison as a single system during all phases of Assembly, Integration and Testing including environmental testing. The main source of power is Solar Panels and the size of these increase with increasing power requirements. Taking into account the size and fragility of the solar panels, normally they are integrated at the last. Therefore, during all ground tests, the major challenge faced is in feeding power to the spacecraft, yet under real conditions. Electronic Solar Array Simulator, an inexpensive, flexible and well protected custom made power supply offers the solution. This can simulate quickly and accurately the true V-l characteristics of solar panels under varying conditions. This paper describes the Solar Array Simulator, designed and developed at ISRO Satellite Centre (ISAC) for new generation of communication satellites which were successfully used during all phases of testing for INSAT-2E and INSAT-3B spacecrafts and also are to be employed for all our future spacecrafts testing.