Analysis and comparison of differential protection principle of transformer based on the different components

This paper analyses the basic principle of the differential protection of fault component ratio and the differential protection of normal ratio and compares the sensitivity of these two kinds of differential protection under the differential fault conditions,getting the result that each protection has its own advantages under the different fault conditions.The dynamic emulation model was established by use of MATLAB and SIMULINK and the advantages of the differential protection of fault component were verified through the high resist- ance grounding fault test.