Numerical Simulation of Arc Motion and Anode Activity Considering the Action of Metal Vapor

The constricted vacuum arc can be controlled by transverse magnetic field (TMF) to make it moving on the contacts. The movement of the arc avoids the excessive ablation of the contact surface, which is benefit for the successful breaking of interrupters. Previous studies have suggested that the speed of arc motion is closely related to the contact surface temperature. Only if the temperature of arc root is high enough, the arc is likely to move forward. However, it is also noted that too high metal vapor pressure near arc would limit its forward process. In this paper, a transient two-dimensional anode activity model (subjected to TMF contacts) is established, with consideration of the limitation of metal vapor. Based on this model, the arc speed and anode thermal process are calculated. In addition, the arc speed and relevant parameters are compared with previous simulation and experimental results.