Erosion Characteristics of SF6 Circuit Breaker Contacts Based on Numerical Simulation

To solve the difficulty in obtaining the variation of the electrical performance of circuit breaker contacts with the erosion through multi-physics field simulation, this paper delves into the nonlinear simulation method of contact travel and surface conductivity changes. A 72.5kV circuit breaker erosion test platform was built to obtain mathematical models of contact travel and quality loss through interpolation method. A simulation model of erosion based on deformation mesh technology was constructed. The results show that the number of erosions affects the distribution of electric field inside circuit breakers. When considering solely the alterations induced by the airflow field, the arc extinguishing capacity of the circuit breaker experiences a substantial decline of approximately 28.38% after 9 erosions at 100% of the rated current.