Study on the Influence of Secondary Electron Emission on Sheath Development in Vacuum Circuit Breakers

The simulation of influence of secondary electron emission on sheath expansion in vacuum arc can be closer to the practical post-arc dielectric recovery process and it is of great significance to perfect the theory of vacuum arc. In this paper, we adopt a PIC-MCC model to simulate the post-arc sheath expansion process with secondary effects of ion bombardment on the electrode based on VSim. The distributions of secondary electron and the influence of secondary electron on sheath expansion under different initial conditions were analyzed. The simulation results showed that the sheath completion time gets a little bit longer with considering the secondary electron emission; The extent of influence of secondary electron gets higher with increasing metal vapor density and it has no difference with changing plasma density and rate of TRV.