The Impact of HVDC Commutation Failure on the Distance Protection

According to the characteristics of distance protection principle and based on PSCAD/EMTDC, this paper first simulates and analyzes the variation characteristics of HVDC equivalent power-frequency current under the different situations of commutation failures. Then based on these, the influence of commutation failure on the measured impedance of distance relay under the different receiving end situations is analyzed. At last, the correctness of theoretical analysis is verified based on PSCAD/EMTDC.