Research On Reliability Of Relay Protection In Intelligent Substation

The reliability of relay protection system is reduced because of a variety of factors,such as overfull intelligent electronic components,complex information types and so on.With the development and application of intelligent substation,it is necessary to study the reliability of intelligent substation relay protection system.According to the characteristics of overfull intelligent electronic components in intelligent substation,complex system structure and so on,the reliability analysis of relay protection system based on system structure was presented in this paper.The reliability block diagram was used to model the relay protection hardware system of intelligent substation.The reliability calculation was carried out by the method of minimal path set disjoint.On the basis of reliability and other indicators,the indicator of rejection probability and false probability were put forward and a comprehensive reliability analysis of relay protection hardware system in intelligent substation was done.On the basis of reliability analysis of system structure,the Birnbaum method was introduced to analyze the importance of intelligent electronic components.The analysis method of reliability was helpful to find the weak link of the relay protection system.The reliability analysis method based on system structure and Birnbaum method were used to program by Matlab.An example was given to demonstrate the effectiveness of the proposed algorithmCombined with the characteristics of information network,the reliability analysis of relay protection system in intelligent substation based on the information flow was carried out.On the basis of Synchronization information flow,SV information flow,GOOSE information flow,the reliability block diagram based on information flow was established.In order to clarify the influence of the information flow on the reliability of each component of the protection system,the correction formula of component reliability was added.And on this basis,the reliability analysis results based on three kinds of information flows were obtained by using the minimal path set disjoint method.Finally,from the two aspects of the hardware system and software system,the measures to improve the reliability of the relay protection system were summarized.And according to the examples,the concrete improved methods were given.The reliability of the improved system based on system structure and information flow was analyzed.An example was given to demonstrate the effectiveness of the reliability improvement measures.