Low earth orbit photovoltaic assembly technology, development and qualification test results

The market demand for earth observation satellites has increased significantly for scientific, commercial and military applications. In order to fulfil the harsh environmental requirements, typical of this type of long lasting missions (up to 5 years on orbit lifetime), Galileo Avionica have developed and qualified a comprehensive set of photovoltaic assembly (PVA) technologies. The achievements obtained so far are not only limited to the electrical parts but cover also other solar generator related issues like the substrate protection against atomic oxygen (ATOX) erosion phenomenon. The development and qualification path started from microsats solar arrays, went through a Si based large deployable solar array wing, dedicated to a 8 months mission at 350 km altitude, and arrived to the qualification of a large deployable GaAs triple junction based solar arrays for up to 5 years missions also suitable for ATOX environment. A strong support to the definition of valuable space products was also given by parallel R & D activities sponsored by the European and Italian Space Agencies.