Droop Control for Microgrids with Variable Inverter Outputs: A Virtual Impedance-Based Adaptive Strategy

With the widespread application of renewable energy sources (RES) in islanded microgrids, the system instability caused by the intermittency of RES generation has also increased. To maintain stability during RES fluctuations, a novel adaptive droop control strategy utilizing adaptive virtual impedance is proposed in this study. This strategy allows the droop coefficients and virtual impedance to adaptively change based on the actual capacity of the inverters, thereby automatically adjusting the inverter output voltage and ensuring proper power sharing even as inverter capacity changes. Moreover, this strategy ensures appropriate power sharing under different load conditions and microgrid configurations. Finally, t he proposed strategy i s validated through MATLAB/Simulink simulations, showcasing its advantages over traditional droop control.