Common-Mode Voltage Reduction in VSI-Fed Motor Drives With an Integrated Active Zero-State Switch

Common-mode voltage (CMV) produced by voltage source inverters (VSI) is of great concern in motor drive systems. A significant amount of conducted common-mode/bearing current will be induced and will interfere with system operation. As an alternative to inserting bulky passive filters to combat the adverse effect by CMV, this article proposes a new topology of integrated active zero-state switch (IAZS). Minor adjustment to the standard space vector pulsewidth modulation (SVPWM) is proposed to facilitate the use of IAZS, which enables CMV reduction in VSI-fed motor drives. Simulation and experimental results on a commercial VSI are presented as proof of concept to validate the effectiveness of the proposed design in CMV reduction.