Vol. 25

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Improved Analytical Model for Surface-Mounted PM Motors Considering Slotting Effects and Armature Reaction

By Thierry Lubin, Smail Mezani, and Abderrezak Rezzoug
Progress In Electromagnetics Research B, Vol. 25, 293-314, 2010


This paper presents an exact analytical method for the computation of the magnetic field distribution in surface-mounted permanent-magnet (PM) motors for any pole and slot combinations including fractional slot machines. The proposed model takes into account the slotting effect and the armature reaction magnetic field. The analytical method is based on the resolution of the two-dimensional Laplace's and Poisson's equations in polar coordinates (by the separation of variables technique) for each subdomain, i.e., magnet, airgap and slots. Magnetic field distributions, back electromotive force and electromagnetic torque (cogging torque and load torque) computed with the proposed analytical method are verified with those obtained from finite element analyses.


Thierry Lubin, Smail Mezani, and Abderrezak Rezzoug, "Improved Analytical Model for Surface-Mounted PM Motors Considering Slotting Effects and Armature Reaction," Progress In Electromagnetics Research B, Vol. 25, 293-314, 2010.


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