3D analytical model for estimation of eddy currentlosses in the magnets of IPM machine considering the reaction field of the induced eddy currents

This paper proposes a closed-form 3D analytical model developed for the estimation of eddy current losses in an interior permanent magnet synchronous machine. Two different types of commonly employed interior permanent magnet machines are considered for the loss analysis. The results of the analytical model are compared with the results from 3D finite element analysis. The proposed model can be directly used to evaluate the eddy current magnet losses for various magnet segmentations in the axial and tangential directions. The influence of air-gap length, PWM carrier frequency, reaction field of induced eddy current and non-linearity of iron on the eddy current magnet losses have been studied in detail and the results are presented. The results from analytical and 3D finite-element analyses were found to be in good concurrence with a maximum difference of 5.9 %.