Synchronous Rotation Coordinates-Based Low Voltage Ride Through Control Technology for Distributed VSG

Traditional virtual synchronous control strategies lack the ability to perform Low Voltage Ride Through (LVRT) in the event of a fault in the distribution network. When the original power command value is high, the steady-state output current may exceed acceptable levels, and the reactive power response time may be sluggish, thereby failing to meet L VRT requirements. This paper suggests an improved L VRT control technology for VSGs using synchronous rotation coordinates. The approach suppresses instantaneous current through virtual impedance and controls output current in sequence. An improved current and power control loop is introduced, allowing the VSG to inject reactive power within a specified time and calculate active and reactive power command values for L VRT requirements. The strategy avoids the impact generated during control mode switching and meets the power grid's LVRT requirements. Simulation results validate the effectiveness of the proposed approach.