Measurement of charge absorption by arc plasma on a solar array surface

Late in 1990, a short-circuit accident occurred on a GEO satellite due to a sustained arc on a high-voltage solar array. The arc plasma generated by a trigger arc absorbs the electrical charge on the coverglass and the conductivity increases. The high-density arc plasma short-circuits the adjacent array strings and the solar array supplies the current to the trigger arc that becomes the sustained arc. The purpose of this paper is to investigate the charge absorption by the arc plasma via a laboratory experiment. Solar array coupons are irradiated by an energetic electron beam in a vacuum chamber. The amount of charge absorbed by the arc plasma is proportional to the differential voltage before the arc. When the initial energy of the trigger arc is small, the charge absorption depends on the distribution of surface potential. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 151(2): 1–11, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20038