Modeling and simulation study on the ablation characteristics of DC contactor contact

Abstract

The DC contactor can frequently break the high current control circuit, and the arc motion characteristic in the current breaking process is closely related to its electrical life and reliability. In this paper, a three-dimensional magnetohydrodynamic arc model of the DC contactor considering contact motion and external circuit characteristics is established. On this basis, the influence of the vapor produced by the contact ablation on the arc behavior is studied, and the ablation rate of the cathode in a single breaking process is calculated. The results show that the arc temperature is reduced, the motion speed is slowed down, and the arc burning time is shortened due to the presence of copper vapor produced by ablation. The ablation rate of the cathode during a single arc is 8.9 µg/C.