PWM method based on the degree of freedom in flying capacitor multilevel inverters

Flying capacitor multilevel inverters are increasingly used in industry applications. In order to improve the harmonic performance of the output voltage under low modulation index region, the paper presents a novel PWM method for flying capacitor multilevel inverters based on the idea of controlling freedom degree. PWM method for flying capacitor multilevel inverters exhibit good performance under both high and low modulation index regions and is capable of balances flying capacitor voltage in a period. Simulation results confirm the validity of this method.