Study and Simulation of VSC-HVDC under AC Power System Faults

In this paper, control strategies of VSC-HVDC aiming to improve the ability of fault ride through of the VSC-HVDC system under serious asymmetric fault at the receiving side was studied. On the basis of DQ decoupling control scheme, two additional fault control modules are proposed based on positive and negative sequence detecting technology. One is based on negative sequence voltage compensation, and the other is based on oscillating active power elimination. Simulations are carried out in PSCAD/EMTDC to verify the validity of the proposed control strategies.