FEA Modelling of Eddy Current Losses on Permanent Magnets

The losses due to eddy currents in permanent magnets of a motor, have significant impact on the magnet temperature and its performance. While designing Battery electric vehicles (BEVs) this can influence the range and the cooling system for the motor assembly. The rare-earth magnets have higher conductivities which leads to significant magnet losses at maximum speed operations. In case of pulse width modulated current input to the 3-phase motor, the high-frequency harmonics can cause considerable rise in the magnet losses. This paper presents a detailed finite element analysis (FEA) modelling which takes into account the 3-D eddy current flow with a magnet to analyze and predict losses in a magnet with higher accuracy.