A study on characteristics of rotor losses for IPMSM considering slot-pole combination

In this paper, we investigated the effect of slot-pole combination on rotor loss in interior permanent magnet synchronous machine (IPMSM) with distributed armature windings. In order to study the characteristics of the rotor losses, two machines for high-speed operation such as electric vehicle were designed. One is fractional slot winding and the other is conventional one. Based on 2-D time-stepped finite element method (FEM) we analyzed both iron loss and eddy-current loss in the permanent magnet of the machines according to their driving conditions. From the analysis results, it was shown that rotor iron loss and eddy-current loss of PM of machine employing fractional slot-winding is definitely large at load condition.