A Fault Ride-through Method of VSG Based on Reactive Power Feedback Coefficient Optimization

Abstract

With the increasing proportion of renewable energy in the grid, the voltage support capacity of the grid becomes weaker and weaker. Virtual synchronous generator (VSG) control has been widely used in renewable energy grid connection because of its excellent reactive power support ability. However, the fault ride-through ability of traditional VSG is weak, and VSG is prone to overcurrent when the power grid short circuit fault occurs. Therefore, this paper proposes a fault ride-through method for VSG based on reactive feedback coefficient optimization. The active power compensation is added to improve the power angle stability of the VSG. The reactive power feedback coefficient is designed based on the maximum output current of VSG to maximize voltage support capacity. Considering the case of a small voltage sag fault, the target voltage adjustment strategy is added to control the output voltage of VSG within the standard operating range. Finally, simulation results demonstrate the effectiveness of the proposed strategy.