Research on reliability evaluation method of protection system based on Kaplan-Meier and GO method

Abstract

In the reliability analysis of the traditional substation protection system, methods such as minimum path set method, fault tree method and Markov method are mostly used. These three methods have disadvantages such as large amount of calculation and strong subjectivity in the application process. Based on the shortcomings of traditional reliability analysis methods, this paper proposes a protection system reliability evaluation method based on survival analysis plus GO method. In view of the problem of timing truncation of the failure data of the protection system and the different time of operation of the protection device, the survival analysis (Kaplan-Meier) method is used to estimate the reliability of the equipment in different time periods, and the GO method is combined to obtain the GO graph of the protection system and GO operation, and then get the reliability of the entire protection system. The results show that the method can quantitatively calculate the reliability of the relay protection system, has the advantages of simplicity, intuitiveness, and easy computer programming. It can be used to analyse the reliability of the relay protection system and guide the design, operation and maintenance of the substation.