Analysis and Development of Short Circuit Capability of 400MVA/500kV Single Phase Autotransformer

At present, 400MVA is the largest capacity transformer with 500kV voltage level in the world for sudden short circuit test. This paper introduces the basic parameters and development structure of the short-circuit prototype with 400MVA/500kV single-phase autotransformer. Based on the electromagnetic force characteristics, the ability to withstand short circuit of high voltage-medium voltage (HV-MV) and medium voltage-low voltage (MV-LV) is analyzed and checked. Compared with the short circuit force of 110kV and 220kV transformers prototype, the short circuit characteristics of 500kV autotransformer are analyzed, and the control strategy is put forward from the material, design and manufacturing technology. Finally, the prototype is verified by the sudden short circuit test of HV-MV and MV-LV modes. The test results show that: the prototype successfully passed the strong current impact, and the test results and various indicators are qualified, which further demonstrates the accuracy of the anti-short-circuit check and the prototype’s strong short-circuit resistance.