Carrier based PWM methods for CMV elimination in open-end winding induction motor drive

A dual two-level inverter utilizing an open-end winding induction motor can synthesize three-level space vector. This paper proposes new carrier phase shifted sinusoidal pulse width modulation (SPWM) methods for a dual two-level inverter. The PWM methods are based on a simple comparison of phase shifted modulating signals with the phase shifted carrier signals. The envisaged PWM methods are aimed at completely eliminating common mode voltage (CMV) in the open-end winding induction motor drive. CMV obtainable with the proposed PWM methods are first analysed theoretically and then simulated and also validated experimentally. The effectiveness of proposed PWM methods in successfully eliminating CMV in the motor drive is demonstrated. Furthermore, comparative evaluation of CMV with the proposed carrier phase shifted SPWM methods and PWM methods existing in the literature is also presented in this paper to showcase the superiority of the proposed PWM methods.