VSC control strategy for HVDC compensating negative sequence and decaying DC components

This paper proposes a voltage source converter (VSC) control strategy for the high voltage direct current (HVDC) transmission systems compensating the negative sequence and decaying DC (DDC) components. The mathematical model of the grid fault current is established firstly, and the DDC component is extracted using the property that the integral of the periodic signal is 0. Secondly, the fundamental wave component of the grid fault current signal is separated in the rotating frame system to obtain the compensation current command of VSC-HVDC. Finally, the performance of the proposed control strategy is compared with the conventional inverter control strategy when compensation the negative sequence and decaying DC (DDC) components by the experimental platform, and the experimental results show that the flexible HVDC transmission system with the proposed control strategy has the desired ability of compensating the negative sequence and DDC components simultaneously