A Study on the Thermal Characteristics of the Permanent Magnet Motor Considering Eddy Current Loss in the Permanent Magnet

This paper deals with BLDCM (Brush-Less Direct Current Motor) and IPMSM (Interior Permanent Magnet Synchronous Motor) which they have same rating torque, rating speed, and size except the shape of magnet and the way of giving exciting currents. Between BLDCM and IPMSM, there are many differences which made a critical performance difference. First of all, revised BLDCM and IPMSM model are suggested by using the basic BLDCM for EPS and the magnetic equivalent circuit. In this paper, harmonic analysis, eddy current loss analysis, and thermal analysis are performed in regular sequence and the results are analyzed to compare the characteristics of BLDCM with IPMSM. As a result, when BLDCM and IPMSM have the same size, same shape except a shape of magnet, same output, IPMSM’s performance is better.