Modified control of Virtual Synchronous Generator for Microgrid Stability Improvement

The power generation from renewable energy sources-based power systems is increasing rapidly, and virtual synchronous generator (VSG) has recently drawn considerable attention. It is anticipated that VSG improve the power and frequency regulation of islanded microgrid. However, the large disturbance and parallel integration of VSG with conventional synchronous generators cause significant fluctuation in power and frequency due to sudden change in the virtual rotor speed of VSG. In order to suppress the effects of these instability elements, a modification is proposed in VSG control. According to the proposed modification, an auxiliary inertia unit is incorporated into VSG control along with additional power loop. Moreover, MATLAB/Simulink simulation is developed to analyze and evaluate the effects of the proposed modification in the islanded microgrid, and the results show the effectiveness of the proposed modification.