Research on Short Circuit Cumulative Effect and Deformation Prediction Method of Transformer Windings

Power transformer is one of the most important electrical equipment in power system operation. Therefore, the calibration of the transformer helps to prevent the abnormal operation of the transformer system timely. A method to consider the cumulative effect of short circuit windings deformation and its deformation prediction is proposed in the paper. Firstly, the mathematical expressions and influencing factors between the accumulated number of short circuit shocks and transformer windings deformation are determined. Secondly, based on COMSOL finite element analysis method, by the actual transformer basic parameters, a three-dimensional finite element simulation model of magnetic and structural coupling field of transformer core and winding is established. The accumulated winding deformation renderings under different short-circuit shock are simulated, and the law between the accumulated number of short circuits and the transformer winding deformation is obtained. Simulation and experimental results prove the feasibility of the theoretical analysis, which provides a reliable method for transformer calibration.