Study on Transient Overvoltage of Wind Farm Caused by Fault of HVDC System and Its Suppression Measures

Faults such as DC commutation failure and DC blocking will generate transient overvoltage at the converter station, and the transient overvoltage will be transitive. If the DC system sending end is a wind farm, transient overvoltage may cause wind turbines overvoltage and then off-gird. The reasons of transient overvoltage caused by commutation failure and DC blocking faults are analyzed. The mechanism of overvoltage that may cause wind turbines off-gird is elaborated. The simulation analyzes wind farm overvoltage under different fault conditions of HVDC, and verifies the effectiveness of measures to suppress transient overvoltage.