Methods of voltage synchronization in multiphase power conversion systems

Abstract

Novel method (methodology) of synchronized pulsewidth modulation (PWM) is powerful instrumentation for elimination of sub-harmonics in the spectra of output voltage of both three-phase and multiphase voltage source inverters. This paper presents examples of dissemination of this new method for control of: a) five-phase inverters; b) six-phase inverters for drive system with symmetrical six-phase induction machine, and c) six-phase inverters for asymmetrical six-phase motor drive. Basic peculiarities of the method have been described. Simulations give a behavior of multiphase drive systems fed by inverters with basic continuous and discontinuous schemes of synchronized PWM, providing quarter-wave symmetry of the phase voltage during the whole control range.