Research of the Influence of Different PWM Inverters on the Iron Losses for Induction Motors

In this paper, iron losses of induction motors driven by the pulse width modulation (PWM) inverters are investigated. Sinusoidal pulse width modulation (SPWM) and space vector modulation (SVM) are two widely-used PWM patterns. However, both SPWM and SVM bring extra iron losses in the induction motors. The difference of iron losses associated with the SPWM and SVM inverter-supplies as well as the sinusoidal mains power supply is comparatively studied, using the time-stepping finite element analysis (FEA). On the other hand, a novel analytical method to predict the iron losses with arbitrary PWM supply is proposed. This method does not require separation of the three components of iron losses, and hence is simple to use in motor design process. The method is validated by the FEM results, exhibiting sufficient accuracy.