Comparative Evaluation of Space Vector Based Pulse Width Modulation Techniques in terms of Harmonic Distortion and Switching Losses

Voltage source inverter (VSI) fed induction motors are widely used in variable speed applications. The harmonic distortion in the line currents of the inverter depends on the switching frequency and the pulse width modulation (PWM) technique employed to switch the inverter. The inverter switching loss is also strongly influenced by the PWM technique used. This paper compares the harmonic distortion and inverter switching losses due to different PWM techniques at a given average switching frequency. The paper evaluates a few specially designed PWM techniques based on space vector approach. It is shown that these techniques lead to reduced line current distortion as well as switching losses compared to well-known techniques such as sine-triangle PWM and conventional space vector PWM (CSVPWM).