Impact of the Voltage Profiles of CHB vs MW-Type Inverters on Torque and Speed Ripples for 3-Phase Induction Motors

Increasing the number of voltage levels in the inverter waveform helps in a better approximation of sinusoidal output and improves the quality by reducing the total harmonic distortion. This paper discusses the impact of voltage waveform quality on the speed and torque profiles of the induction motor using the cascaded H-bridge 11-level inverter and the modified-W-type inverter. The impact of the variation in motor parameters on the speed and torque waveforms has also been discussed. It has been shown that the speed and torque ripples of the inverter-fed machine are significantly affected by the voltage profile and the firing instants of the switches in the inverter circuits.