Research on Movable Conditioning Test Method and Device Development of Vacuum Circuit Breaker for 40.5kV Capacitor Bank

The restrike of vacuum circuit breaker in capacitor bank seriously affects the reliable operation of reactive power compensation in power grid. High voltage and high current conditioning test can effectively improve the breaking capacity and stability and reduce the restrike rate. However, at present, the conditioning test is carried out on the circuit of the breaking test, which is complex and huge. It is difficult to configure for the manufacturing plant and the operation site, the quality of the factory conditioning is not good. Movable vacuum circuit breaker conditioning device become an urgent need for material acceptance and on-site operation and maintenance. In this paper, a movable conditioning test method and parameters are proposed, and a 40.5kV test device is developed. A capacitor discharge circuit is used for closing conditioning. By applying dynamic recovery voltages with different rise rates for no-load breaking, multiple restrikes are generated to perform breaking conditioning, and the anti-restrike performance is quantitatively evaluated according to the withstand recovery voltage level. Based on this, the first 40.5kV movable conditioning test detection device was developed and the effectiveness of device was verified. After the test, it was found that the contact surface was smooth, and there was a certain depth of melting spots evenly distributed, which further demonstrating the effectiveness of the device conditioning from the micro level. It shows that the movable device can be easily used for conditioning test and quantitative evaluation of anti-restrike performance in material acceptance, on-site operation and maintenance, ex-factory and other occasions.¹