A Dynamic Response Optimization Strategy for Grid-connected Active Power of Energy Storage Virtual Synchronous Generator

The energy storage virtual synchronous generator (VSG) can provide certain inertia support for the renewable energy power generation system, but its virtual damping coefficient is coupled with the primary frequency modulation coefficient, so the dynamic oscillation and the steady-state error of its grid-tied active power cannot be eliminated simultaneously when the active power command and the grid frequency are disturbed. Therefore, a dynamic response optimization strategy based on the improved virtual impedance for the energy storage VSG is proposed in this paper, which introduces the virtual impedance into the voltage control link in the conventional VSG control strategy. The proposed method can not only improve the system damping but also suppress the dynamic oscillation of grid-connected active power without any steady-state deviation. The correctness of the theoretical analysis and the effectiveness of the proposed control strategy are verified by simulation results.