Combined synchronized PWM for dual neutral-clamped converters for asymmetrical split-phase traction drive

The paper presents results of analysis of operation of asymmetrical split-phase (six-phase) electric vehicle drive on the base of two neutral-clamped converters, controlled by combined schemes of synchronized pulsewidth modulation (PWM), providing both common-mode voltage cancellation and continuous synchronization of the output voltage of inverters during the whole control diapason. Simulations give behaviour of the systems with synchronized space-vector modulation. Phase voltages of dual three-phase (split-phase) drives with synchronized PWM have symmetry during the whole control range including overmodulation, and their spectra do not contain even harmonics and subharmonics, which is especially important for high power/current systems.