Vacuum Arc Circuit Breaker Post-Arc Plasma Decay Model

This document presents a hybrid model (fluid for electrons, particles for ions) to simulate plasma decay and cathode sheath growth in vacuum arc circuit breakers during the post-arc phase, focusing on the risk of restriking due to transient recovery voltage (TRV). It also provides industrial context on medium voltage breaking technologies, comparing vacuum and SF6 methods, and explains the physics of arc interruption and residual plasma management.