Novel schemes of synchronous PWM for dual inverter-fed drives with cancellation of the zero sequence currents

The paper presents results of application of new methods of synchronous pulsewidth modulation (PWM) for control of a dual inverter-fed open-end winding induction motor drive. Special attention has been given in this paper to analysis of processes in this system in the zone of over modulation. The phase-shifting-based scheme of synchronous PWM for dual inverter-fed drive provides elimination of zero sequence currents in the load. Simulations give the behavior of the systems with continuous and discontinuous PWM. The spectra of the phase voltages of drive systems with algorithms of synchronous PWM do not contain even harmonics and sub-harmonics (combined harmonics), which is especially important for the systems with increased power rating