A reference current cross-feedforward stability control strategy for grid-connected inverter

Grid-connected inverter is widely used as interfaces between renewable energy sources and the power grid. However, under weak grid conditions, fluctuations in grid impedance can cause instability and current distortion when using conventional control strategies. To address this, a stability control strategy based on reference current cross-feedforward is proposed. By introducing the cross-feedforward term into the conventional dq-axis current references, the method maintains a simple structure and is easy to implement. Generalized Nyquist criterion analysis shows that it broadens the stability range and enables full-power operation under weak grid conditions. The efficacy of the proposed strategy is confirmed by simulation results.