Investigation of common-mode voltages of PWM inverter with a small capacity auxiliary inverter

This paper presents a dual-bridge inverter approach to eliminate the motor common-mode voltage. This inverter which consists of two inverters to be connected in parallel does not generate the common-mode voltage, and can drive standard three-phase three-wire induction motors. Additionally, because one inverter does not output active power, the capacity of the inverter is very small. The effectiveness of the proposed method is verified experimentally.