On the analytical calculation of eddy-current losses in permanent magnets of electrical machines

Eddy-current losses in permanent magnets of a surface-mounted permanent-magnet synchronous machine (SPMSM) are analytically calculated by solving magnetostatic and magnetodynamic field problems. The magnetostatic solution neglects the eddy-current reaction fields and depicts a large deviation compared to a Finite Element Analysis (FEA). A correction factor introduced into the magnetostatic calculation does not provide sufficient accuracy at high frequencies. The magnetodynamic calculation, which takes the eddy-current reaction fields into account, achieves a good agreement with a Finite Element Analysis.