Particular Model for Efficient Switching Frequency Loss Consideration in Surface Mounted Permanent Magnets

This article proposes a particular modeling procedure for efficient switching frequency loss consideration in surface mounted permanent magnet rotors in cases of pulse width modulation (PWM) supply. The model is based on 2-D finite-element analysis (FEA) combined with circuit equations in the permanent magnet regions enabling end effects consideration associated with the switching frequency, which is responsible for the major part of eddy current losses in the magnets. The model’s accuracy is validated through measurements in a magnetic circuit. Comparison between measured and simulation losses by implementing a traditional loss separation analysis has illustrated the relative dominance of switching frequency eddy current losses in permanent magnets and the feasibility of the proposed methodology.