A three-phase inverter off-grid operation control method and system

Abstract

This invention provides a method and system for controlling the off-grid operation of a three-phase inverter, belonging to the field of power electronics technology. The method includes the following steps: acquiring the three-phase output voltage and three-phase output current of the inverter; processing the acquired three-phase output voltage and current signals to generate a basic modulation wave signal; acquiring the zero-sequence voltage of the inverter and generating a modulation wave compensation signal through a zero-sequence voltage regulator; superimposing the basic modulation wave signal and the modulation wave compensation signal to generate a final modulation wave signal; and processing the final modulation wave signal through a power conversion module to generate a switching control signal. This invention, by introducing zero-sequence voltage closed-loop control, effectively suppresses the zero-sequence voltage component generated by the three-phase inverter under unbalanced loads, ensuring the symmetry and stability of the output voltage, and solving the problem of insufficient performance of traditional control methods under unbalanced loads.

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