Magnet eddy current loss calculation method for segmentation analysis on permanent magnet machines

Abstract

Eddy current losses generated in the rotor of permanent magnet machines may lead to an excessive magnet heating. This can cause the magnets to get fully demagnetized so it is very important to analyze the losses on them. In high power application usually it is necessary to design solutions to reduce eddy current losses. The most common technique is the magnet segmentation. Analytical calculation of magnet eddy current losses may give some inaccuracies on the results and FEM analysis may be too time-consuming in some design steps. A new method that combines FEM and numerical calculations to evaluate the losses for different magnet segmentation is presented in this paper.