Power sharing of parallel inverters based on Andronov-Hopf virtual oscillator controller

Abstract

 This paper proposes a distributed control structure for two single-phase voltage-source inverters (VSIs) operating in parallel within a stand-alone microgrid, without requiring any communication links. The control framework is based on the Andronov–Hopf Virtual Oscillator Control (VOC) scheme integrated with a virtual impedance block, a proportional–resonant (PR) controller, and a disturbance observer (DOB). This configuration enables the inverters to self-synchronize their voltage, current, and frequency while achieving effective

power sharing, even when the line impedances between the inverters and the loads differ or vary with location. The proposed structure is simulated in MATLAB/Simulink and experimentally validated on a DSP TMS320F28377S platform with each inverter rated at 3 kW. Experimental results show a maximum power-sharing deviation of 4.2%, voltage total harmonic distortion (THD) below 5%, and a recovery time of less than 0.08 s during inverter connection or disconnection, demonstrating stable, reliable operation with improved voltage quality and accurate power sharing in stand-alone microgrids.