Research on Classification Evaluation Method of Capacitive Breaking Capacity of Vacuum Circuit Breaker

Vacuum circuit breaker has the advantages of small size, strong opening, closing ability and green environmental protection, is widely used in the switching of parallel reactive compensation capacitor banks in 35kV and below distribution network. Vacuum circuit breaker will produce pre-strike when shunt capacitor bank is switched, the high frequency arc will cause ablation and even fusion welding on the contact surface, which will affect the capacitive breaking performance. Therefore, it is great significance for the reliable operation of the distribution network to accurately evaluate the breaking capacity of the vacuum circuit breaker of the switching capacitor bank. Aiming at the reactive power compensation of capacitor banks, a classification evaluation method for capacitive opening and closing capacity of circuit breaker is proposed. By applying the dynamic recovery voltage to the vacuum circuit breaker when no load is broken, the strike occurs many times in the process of breaking, and the capacitive breaking ability of the circuit breaker is evaluated according to the drawn dielectric recovery characteristic curve. According to the test results of circuit breakers with different performance states, the breaking position parameters are determined, and the capacitive breaking capacity of vacuum circuit breaker is quantitatively evaluated. Through the breaking performance evaluation test of different design circuit breakers and the C2 class type test, the reasonable validity of the proposed method is verified from multiple dimensions through the comparison of test results.