Analysis of fault characteristics of AC outlets in the interconnected operation of VSC HVDC power grid

The fault analysis of AC outlets in VSC HVDC power grid is the basis of AC protection configuration. This paper analyzes the influence of negative sequence suppression strategy on negative sequence current and positive and negative sequence voltage of converter station, studies the influence of outer loop limiting controller on short-circuit current, analyzes the mechanism of low-voltage limiting strategy on positive sequence current, and obtained the impedance angle of AC outlets fault in VSC HVDC power grid, The simulation results show that the control strategy has an effect on the amplitude and phase angle of the short-circuit current. This study provides a basis for the analysis of the influence of the VSC HVDC power grid on the AC protection.