Reliability analysis of vacuum circuit breaker with permanent magnet material actuator based on competitive failure model

Of late, the permanent magnetic actuator has been used widely in the vacuum circuit breaker. The permanent magnet mechanism explored in this paper adopts the NdFeB permanent magnet. An important indicator of its reliability is the mechanical life of the vacuum circuit breakers (VCBs). In this study, 12 KV permanent magnet-operated VCBs have been tested for their mechanical fidelity. With the degradation failure following the Gaussian process and the traumatic failure of the Weibull distribution, the competition failure model has been established by considering the correlation between the two failure modes. The model parameter estimation was determined using the EM algorithm. Eventually, the reliability of the model was attained. This paper evaluates the results of different methods have been compared and analysed, which further proved that the method proposed in this paper had better evaluation accuracy and certain specific value for engineering application.