Two-dimensional simulation of the post-arc phase of a vacuum circuit breaker

The post-arc phase of a vacuum circuit breaker is a critical phase for dielectric recovery in the context of medium voltage current interruption. A 2-D hybrid model aimed at understanding this phase and at evaluating the risk of circuit-breaking failure during this phase has been developed. In this paper, we show how the recovery voltage expels the plasma from the gap and illustrate the influence of the shield polarity. Index Terms--Dielectric recovery, plasma sheaths, post-arc phase, vacuum circuit breakers.