Abstract:There is a huge short-circuit electromagnetic force in short-circuited condition for power transformer. When short-circuit electromagnetic force is too large, it will cause the transformer winding deformation. In this paper, a 50MV·A three-phase three-winding transformer is taken as an example. The short circuit current in three-phase symmetrical short-circuited condition for transformer is calculated and took as an excitation in finite element analysis. Then the short-circuit electromotive force of winding is calculated by finite element software. The magnetic-structure coupling method is used to calculate the winding deformation and stress distribution under the maximum short-circuit electromagnetic force. The results show that the low-voltage winding is subjected to the radial electromagnetic force compressed inward and the axial electromagnetic force compressed toward the middle during short-circuit. The short-circuit electromagnetic force that acts on the middle part of the winding is greater than the two ends, which causes the deformation of the middle part of the winding to be greater than the two ends. The research results have certain practical significance for related researches such as transformer winding deformation.