Capacitor Voltage Balancing Control Strategy for Flying Capacitor Multilevel Inverter

The flying capacitor multilevel inverter can reduce the voltage at both ends of the filter inductor through the multilevel output. At the same time, the carrier phase shift modulation is used to improve the equivalent working frequency of the circuit, significantly reduce the volume of passive components such as the filter inductor and improve the power density. Aiming at flying capacitor multilevel inverter, this paper analyzes the influence of different switching states on the capacitor voltage, and proposes a voltage control strategy to maintain the stability of capacitor voltage by adjusting the duty cycle to ensure the reliable operation of the circuit. Finally, the effectiveness of the proposed strategy is verified by simulation and experiment.