Abstract:

Mechanical fault information is rich in the vibration signal during the closing and opening process of HV circuit breaker,the study on the mechanical diagnosis of circuit breaker based on vibration signal information is of practical value in the engineering.To promote the efficiency of the signal acquisition during the closing and opening process of HV circuit breaker,a two-step identification method of the breakpoint in closing and opening vibration process of HV circuit breaker is proposed.Firstly,the sudden change is preliminary detected by the dynamic heteroscedasticity test in the first step.Secondly,the breakpoint is detected by conditional variance test based on the potential mutation moment set in the second step.Moreover,the switching mechanism of the signal acquisition channel is proposed,and the acquisition efficiency is promoted without the additional hardware.Finally,the practical application in Jiangsu power grid verifies the effectiveness of the proposed two step identification method.

Key words: HV circuit breaker, mechanical fault diagnosis, online monitoring, breakpoint, intelligent maintenance