Resonance Suppression Strategy of the Multi-inverter Grid-connected System Based on Current Given Correction

The grid-current-feedback-active-damping control strategy (GCFAD) can suppress the resonance without requiring additional sensors. The GCFAD strategy is often used together with the grid voltage feedforward strategy to suppress background harmonic in the weak and disturbed grid. However, it is found that the positive resistance characteristics of the virtual impedance in the middle, which reduce the robustness of the system. In order to improve the robustness, this paper proposes a high robustness grid-current-feedback-active-damping strategy (HR-GCFAD) and a method of current given correction, which can improve the robustness of the multi-inverter system, and is more adaptable to changes in the number of inverters in the system.