Rectifier Transient Voltage Stability Improvement Strategy Based on Mode Switching

When a serious fault occurs in the power grid, the transient voltage of the rectifier may be unstable, and then the system will collapse. To solve this problem, a control strategy for transient voltage stability improvement of rectifier based on mode-switching is proposed in this paper. Firstly, the basic control structure of the rectifier is introduced, and the state-space model of the rectifier is established. Secondly, the rectifier's transient voltage stability improvement control strategy based on mode-switching is introduced, and the transient voltage instability mechanism of the rectifier is revealed based on P-V curve. Then the influence mechanism of the proposed control strategy on the rectifier voltage stability improvement is revealed. Finally, the effectiveness of the proposed control method is verified in PSCAD/EMTDC simulation. The simulation results show that the mode switching control can avoid the unstable equilibrium point and improve the transient voltage stability of the rectifier.