Where do negatively biased solar arrays arc?

Computer particle simulation of high-voltage solar array arcing onset

“…They are sometimes but not always associated with the inter connect or. 6 In recent theoretical work, Cho and Hastings 1 studied the charging of the region near the plasma, dielectric, and conductor interface. The study was based on the two previous theoretical models by Parks etal.…”

“…The theory is compared to the Japanese Space Flyer Unit High-Voltage Solar Array ground experiment and shown to give a reasonable explanation for data relating the arcing rate to the solar array temperature. 6 x 10 4 -52^1/2 /0 w , A/V 2 =6.53x 10 9 </>J; 5 , V/m -field enhancement factor induced by ion current = mean speed of gas, m/s = thickness of dielectric material d\ + d 2 , m = thickness of co verglass, m = thickness of adhesive, m = electric field, V/m = initial conductor (cathode) electric field, V/m -desorption energy, eV = electron incident energy, eV = electron incident energy for maximum secondary electron yield, eV = secondary electron emission energy, eV -electron incident energy to give secondary electron yield unity, eV = electric field parallel to dielectric side surface, V/m = electric field perpendicular to dielectric side surface, V/m = total current, A = current per unit length in the direction parallel to dielectric side surface, A/m -current per unit length in the direction perpendicular to dielectric side surface, A/m = incident electron current density to dielectric surface, A/m 2 = quasisteady incident electron current density to dielectric surface, A/m 2 = prebreakdown current density from conductor (cathode) before ionization begins, A/m 2 = enhanced field electron emission current density from conductor surface, A/m 2 = quasisteady current density due to negative space charge, A/m 2 = ion current density to conductor due to ionization of neutral, A/m 2 Received Jan. 18,1992; revision received Sept. 16,1992; accepted for publication Sept. 26, 1992 = desorption rate coefficient, s -1 = particle mass, kg = number of gas particles adsorbed per unit area, m~2 = adsorbed neutral surface density for monolayer coverage, m~2 = neutral density, m~3 = ambient neutral density, m~3 = critical neutral density for arcing onset, m~3 = pressure, Torr = particle charge, C = electron impact desorption cross section, m~2 = emission area at metal-dielectric interface, m 2 = emission area at dielectric-vacuum interface, m 2 = sticking probability of neutral particle to dielectric surface = temperature, K = neutral temperature, K = surface temperature, K = bias voltage, V .…”