Conceptual Design and Assessment of an Electrostatic Discharge and Flashover Detector on Spacecraft Solar Panels

This paper presents a concept of monitor aiming at measuring the electrostatic discharge (ESD) occurrence and, possibly, a flashover expansion on spacecraft photovoltaic solar panels. The passive measurement of solar cell cover glass surface potential is used as a diagnostic. The monitor consists of small metallic plates located on the sunlit solar panel. With a sufficient electrical insulation from the spacecraft structure, these plates float to the same potential as the surrounding cover glasses. The photoemission is the physical phenomenon allowing the homogenization of the local surface potentials. Theoretical, numerical, and experimental investigations are used to assess how well such a device could record the evolution of the solar panel surface voltage. Combined with a dedicated measurement chain and telemetry, ESD occurrences could thus be measured on in-flight solar panels.