A Droop Control Strategy Based on Synchronous Rectifier to Modulate the Frequency and Voltage in AC Microgrid

In this paper, we propose a droop control strategy based on synchronous rectifier to improve the voltage quality for AC microgrid. First of all, the virtual synchronous machine (VSM) technology is applied to three-phase PWM rectifier, which makes three-phase PWM rectifier possess the similar damping characteristic and droop mechanism as synchronous machine. Secondly, combined with the droop characteristics of synchronous machine, we design frequency droop control and voltage droop control strategies to respectively suppress the frequency and voltage fluctuation of AC bus caused by change of load in AC microgrid. The proposed control strategies are verified by simulation results in MATLAB/Simulink.