Evaluation of Transformer Thermal Performance during Short-circuit test

Transformer is an important component in the electric grid. Several tests have been defined in relevant standards to ensure reliability of the transformer. Short-circuit test is the one of the critical tests for transformer design verification. Any weakness in design results in the failure of transformer’s short-circuit test. Present paper discusses the thermal performance of the transformer during short-circuit test.Since the transformer experiences excessive amount of current during short-circuit test, transformer winding experiences mainly mechanical stress and thermal stress. Thermal stress shall result in increase in winding temperature. Transformer winding temperature during short-circuit test can be calculated using formulae given in IS/IEC and IEEE. Efforts are made to measure transformer winding temperature during short-circuit test. Comparison is established between calculated and measured transformer winding temperatures during short-circuit test.