A Fault Diagnosis Method for 500kV One-and-a-half Connection System Based on Hierarchical Transition WFPN

Abstract

One-and-a-half connection mode is a method with high reliability, convenient for overhauling, therefore it is widely applied in 500kV power transmission system. Based on traditional Petri net and combined with hierarchical and directional principle of fault, Gaussian distribution and the protective relaying configuration for 500kV one-and-a-half connection system, this paper designs a new pattern of fault diagnosis method for 500kV one-and-a-half connection system based on hierarchical transition WFPN. Meanwhile, considering existence of dead-zone fault, a new topologyis designed to prevent misjudgment caused by dead-zone fault. After confirmation of fault components, a reverse searching method is also designed, able to automatically issue a simple report on the fault of related protective relays and circuit breakers. The fault diagnosis method has the advantages of simple principle and high expandability. It can quickly and automatically obtain a malfunction report at fault occurrence with relatively high fault tolerance. It is helpful for identification of the fault at dispatcher and development of self-healing power grid.