Electrostatic Discharge Tests of Solar Array Coupons With Different String-to-String Gaps Without RTV Adhesive Grout

A series of electrostatic discharge (ESD) tests was performed on solar array test coupons consisting of triple-junction InGaP
₂
/GaAs/Ge solar cells. The string-to-string parallel gaps were not grouted with RTV adhesives. Various combinations of the gap width, the load voltage, and the string current were tested in a vacuum chamber equipped with an electron beam gun to investigate the threshold of secondary arcs. The ESD test circuit included simulated panel coverglass flashover. The insulation resistance between strings was found to decrease as the number of secondary arcs accumulates in the gap.