Commutation Failure Prevention Strategy of HVDC Based on Current and Voltage Prediction

With the rapid development of AC/DC hybrid power grid in China, the commutation failure of HVDC transmission commutation has become one of the key factors that seriously threaten the safe and stable operation of power network. To design a reasonable commutation failure prevention strategy is an effective means to ensure the safe and stable operation of AC/DC hybrid power grid. However, the existing commutation failure prevention strategies will fail under some conditions or even aggravate the commutation failure. Aiming at this phenomenon, based on the analysis of the principle and deficiency of the existing commutation failure prevention (CFPREV) control, the influence of DC current increment on commutation failure in transient process was studied. A commutation failure prevention control strategy based on double prediction of DC current and AC voltage and its parameter tuning method were proposed. Finally, the CIGRE-HVDC standard test model and Henan UHVDC transmission model were taken as examples to verify the effectiveness of the proposed control strategy in suppressing different types of commutation failures, and thus prove its superiority compared to the existing CFPREV. © 2022 Chin.Soc.for Elec.Eng.