Method for Power Grid Fault Identification and Cause Analysis Considering Environmental Information

The existing fault diagnosis methods have three problems: lack of effective use of external environmental information, lack of fault cause analysis, curing of the weight of each fault diagnosis. This paper designs an improved power grid fault identification and cause analysis method considering the network topology, relay protection information and external environment information, which can adjust its weight according to the relevance of the information. First, aiming at curing of the weight of each fault diagnosis, the AHP weight analysis method is used to give high credibility information large weight, reduce the impact of false-alarm and miss-alarm, and improve the accuracy of fault diagnosis. Second, this paper introduces external environmental information (taking the type of information and its alarm level into account) as the criterion for fault cause analysis, and applies the fuzzy comprehensive evaluation method for fault risk assessment to determine whether the fault is caused by external factors. Finally, the effectiveness of the proposed method is verified by the simulation examples under the failure scenarios of protection action alarm information false alarm and miss alarm, and circuit breaker false operation and fail operation.