Analysis and Treatment of A 220kV Transformer Winding Deformation Due to A Single-phase Short-circuit Fault

With the increasing capacity of the power grid, the transformer damage accidents caused by short circuit faults are on the rise. Timely and effectively take detection means to test the transformer winding deformation, which can effectively prevent the further deterioration of the existing deformation of the transformer and ensure that the transformer will not have accidents to the maximum extent. At present, frequency response method, low voltage short circuit impedance method and sweep frequency impedance method are mainly used for field measurement of winding deformation of power transformers at home and abroad. In this paper, the frequency response method and the low voltage impedance method are used to evaluate the winding deformation of a 220kV transformer after a station failure, and the correctness of the evaluation conclusion is verified by the disassembly inspection. When field testing, it is recommended to use two or more methods for assessment to improve the accuracy of the assessment results.