Analysis on transient commutation failure fault on converter valve

The fault current caused by commutation failure seriously affects the secure operation of HVDC power transmission system. At present, the attention of the research on the mechanism of transient after the occurrence of commutation failure is paid to the converter that is regarded as ideal switch, in this paper, utilizing the method based on superposition principle and equivalent analysis the influences of actual valve parameters on fault current are taken into account, and by means of constructing a PSCAD simulation model, in which the 12-pulse converter used in actual converter valves is considered, the waveforms from simulation results are compared with the results from theoretical analysis to verify the correctness of theoretical analysis method.