Electrical Breakdown Triggered by Micro Particle in Vacuum Gap

Abstract

Insulation performance of vacuum decreases with micro particles. Particle-triggered breakdown phenomenon, which occurs when particle approaches and collides with electrode, was observed and the cause of the breakdown was investigated. It was found out that key factor of the breakdown was not particle impact speed but instantaneous field formed near the electrode with approaching-particle. The electric field at the particle collision was numerically computed changing the particle charge and the particle configuration. It turned out that big particle would cause breakdown easily. This coincides well with the experimental result.