Rapid reactive power control method for parallel inverters using resistive-capacitive output impedance

For parallel multi-inverters, an inverter using resistive-capacitive output impedance (RC-inverter) is proposed. The equivalent output impedances of RC-inverter are designed as resistive-capacitance by introducing virtual resistive-capacitive impedance into the feedback of output current. RC-inverters can not only provide rapid reactive power for low-voltage microgrid to maintain the system voltage stability, but also restrain high frequency resonance between output impedance of inverters and the grid impedance. Based on the equivalent modeling of RC-inverter, a multi-loop power sharing control method for parallel inverters is presented, which mainly includes the outer power droop control, the virtual impedance, and the output voltage control. The simulation and experimental results verify the validity of the proposed control method.