Research on commutation failure in HVDC transmission system Part 1:Commutation failure factors analysis

Commutation failure,one of the most common faults in HVDC(High Voltage Direct Cur-rent )system,is related to many factors,such as voltage of commutation bus,ratio of converter trans-former,DC current ,firing angle,commutating voltage zero-crossing phase shift for system unsymmet rical fault,firing pulse control system of converter,AC system frequency spectrum and so on.Based on the CIGRE HVDC benchmark model,the affect of these factors on commutation failure in the inverter is analyzed in detail and the general rules of commutation failure are obtained.