Abstract
The number of electrostatic discharge (ESD) accidents on solar arrays has been increasing. Such accidents can cause serious problems for power generation, such as halting the normal operations of a satellite. To prevent ESD, ground checks should be performed under a normal potential gradient, i.e., when the satellite surface potential is negative with respect to space plasma. In this study, we obtained ESD parameters to establish a method for ground testing. Experiments were performed in a vacuum chamber with an electron gun. Discharge images (propagation length and velocity) were captured by an IR camera. The charge flowing into the discharge point was captured by a current probe. A non-contact surface potential probe measured 2D-potential distributions on test samples. As a result, we found that the threshold voltage of the electrical discharge was −10 kV and the amount of electric charge depended on the propagation area of the discharge plasma. The propagation velocity in a normal gradient potential was 105 m/s.
