Microgrid multi-inverter parallel-control method based on frequency division virtual complex impedance

The invention discloses a microgrid multi-inverter parallel-control method based on frequency division virtual complex impedance, which is suitable for a multi-inverter parallel-control system with a nonlinear load for a low-voltage microgrid. The microgrid multi-inverter parallel-control method comprises the following steps: performing frequency division on a line current by virtue of a band pass filter by adopting a robust droop control strategy of resistance equivalent output impedance, simultaneously multiplying a fundamental current by a virtual complex impedance containing a resistance-capacitance component, designing that each parallel connection inverter output impedance is resistive in a fundamental band; and respectively multiplying each high-frequency current by different virtual inductive impedances, indicating that a harmonic frequency band inverter output impedance is inductive so as to be limited by the robust droop control strategy of resistance equivalent output impedance, so that the influence of a high-frequency harmonic current to inverter parallel-control is avoided. According to the microgrid multi-inverter parallel-control method, the defect of a conventional method is overcome, and good control effect is achieved in the multi-inverter parallel-control system with the nonlinear load for the low-voltage microgrid.