A deadbeat control method for VSC-HVDC under AC voltage unbalance

The mathematical models and power balance relation of VSC-HVDC under AC voltage unbalance were studied in this paper. Based on the mathematical model and the power relations, a kind of negative sequence voltage compensating control strategy was proposed to suppress the negative sequence current. To provide accurate and quick tracking of the generated active and reactive current trajectories, deadbeat control was applied to the positive sequence current inner loop control. The simulation results show that the proposed control strategy not only can suppress the negative sequence current effectively, but also mitigate 2
^nd
harmonic ripple.