Voltage and Current Harmonics Evaluation of Reduced Common-mode Voltage PWM Methods in Adjustable Speed Drives

Common-mode voltage (CMV) in three-phase voltage source inverters (VSI), introduced by employing pulse-width modulation (PWM), can be detrimental to adjustable speed drives (ASDs). In this paper, three typical reduced common-mode voltage PWM methods: active zero state PWM (AZSPWM), remote state PWM (RSPWM), and near state PWM (NSPWM) are quantitatively evaluated, in comparison with the standard space vector PWM (SVPWM). The output voltage linearity region, total harmonic distortion of phase currents, and common-mode voltage behavior associated with each PWM method are examined and evaluated thoroughly in digital simulation and experiments.