ARC MITIGATION ON HIGH-VOLTAGE SOLAR-ARRAYS

In response to the increasing demand for higher power sources in space, solar arrays are being designed with high voltages at low currents to meet this need. Unfortunately, negatively biased high voltage solar cells have been observed to arc when exposed to the low-Earth-orbit plasma environment. Analytical and numerical models of this arcing phenomenon for conventionally designed solar cells have been developed which show excellent agreement with experimental data. With an understanding of a mechanism for arcing, it is possible to assess mitigation strategies and quantify their effectiveness. It was determined that the arcing rate can be decreased by 1) increasing the interconnector work function, 2) increasing the thickness of the coverglass and cover adhesive, 3) decreasing the secondary electron yield of the coverglass and adhesive, 4) decreasing the ratio of the coverglass/adhesive dielectric constants, and 5) overhanging the coverglass. Of these, methods 4 and 5 show the most promise in mitigating or even eliminating arcing.