Emergency Control Strategy Study on Multi-Send HVDC Project from Central China to East China Power Grid

In the summer peak load operation mode of the interconnected power grid which is integrated with HVDC transmission lines from Central China power grid to East China power grid, security and stability emergency control strategies based on generator shedding and EDCPS (Emergency DC Power Support) are studied to cope with system instability caused by Tuanlin-Fengjing DC line unipolar block fault. Simulation results show that interconnected system cannot maintain the transient stability effectively by using EDCPS only. A coordinated control strategy which combines generator shedding with EDCPS is proposed to reduce the number of generators to be shed and ensure the transient stability. Through optimizing EDCPS which two or more HVDC lines participate in, an optimal coordinated control strategy is proposed. Simulation results present that the strategy which combines GC shedding with Longzheng DC bipolar supporting is the optimal strategy.