Analysis of Solar Array Performance Degradation During Simulated Flashover Discharge Experiments on a Full Panel and Using a Simulator Circuit

Abstract

The main activity of the European Space Agency EMAGS3 study (published at 12th Spacecraft Charging Technology Conference Kitakyushu, Japan) was to simulate in-orbit electrostatic discharge, called flashover, on a flight representative panel of dimensions 2 m $\times \,\, 4$ m in an environment to achieve inverted gradient conditions on the solar cells. Electrical performance was measured after the panel has suffered from about 1400 flashovers, some 300 have been recorded and at least 24 of them covered more than 75% of the surface. The comparison with the last measurements before testing revealed no degradation beyond 1%. Obvious differences in the shape of the obtained curves could be attributed to increased serial resistances in the test circuit. A flashover simulation circuit was designed to reproduce the pulse shape measured on the panel. Experiments on single cells using this circuit demonstrated its ability to substitute the flashover in ground tests.