Analytical Computation of Permanent Magnet Eddy Current Loss in Surface Mounted Machines Considering Circumferential Segmentations

Accurate computation of eddy current losses is very crucial for permanent magnet (PM) machines. These losses significantly affect the electromagnetic performance and temperature of the PM, which can cause irreversible demagnetization. In this paper, eddy current losses in the permanent magnet machine with fractional slots concentrated winding configuration is investigated analytically. A complete analytical method considering circumferential magnet segmentation is presented. The results computed by the proposed method are validated by finite element (FE) simulations with different slot/pole combinations of inner and outer rotor designs. The proposed analytical method is useful to predict eddy current loss in the magnet with acceptable accuracy but in a very computationally efficient way.