Establishment of transformer turn-to-turn fault model based on relay protection management system

This paper describes a method to establish turn-to-turn fault model of transformer based on fault analysis expert system. This method can be an advanced application function to be merged into protective relay management system. This paper also establishes differential equations of multi-winding transformer. The turn-to-turn fault winding can be divided to two parts: normal winding and fault winding. The Lest Square Method (LSM) can be used to estimate the self-inductance and mutual inductance values. Then, the fault winding leakage factor can be estimated and the leakage factor curve can be obtained. According to the curve, the turn-to-turn fault model of transformer can be established. Using EMTP simulation tool, the turn-to-turn fault of transformer can be simulated. The dynamic simulation test validates the proposed method in this paper.