Validation objective
Topology IPMSM
Model Types Electromagnetic subdomain model EM2.SPMSM
Electromagnetic linear magnetostatic FEM EM3.PMSM
Quantities Airgap radial and tangential armature flux density waveforms
Geometry Internal rotor
Semi-closed slots
Winding Single layer non-overlapping windings with "alternate teeth wound"


This validation simulates a machine that can be found in the article : A. Rahideh and T. Korakianitis, “Analytical Magnetic Field Calculation of Slotted Brushless Permanent-Magnet Machines With Surface Inset Magnets,” vol. 48, no. 10, pp. 2633–2649, 2012.

This IPMSM (Inset Permanent Magnet Synchronous Machine) has 6 stator slots for 2 poles pairs (6s/4p). The airgap field computation is done in 4 distinct subdomains : airgap, stator slots, stator slots openings, and inset permanent magnet (IPM) with air space at each side.
Stator slots are filled with single layer non-overlapping "concentrated" tooth windings with "alternate teeth wound".
The IPM magnetization pattern is radial magnetization.
An "exact" semi-analytical subdomain model was developped and compared to FEM.

Topology of machine IPMSM_001
Topology of machine IPMSM_001
Manatee model for machine IPMSM_001
Manatee model for machine IPMSM_001


The same model is implemented on MANATEE. The figure below shows the comparison between airgap radial and tangential flux density waveforms obtained by both subdomain model and FEMM (See the different Electromagnetic Modules).

10. Radial airgap flux comparison (FEMM vs Subdomain)
Radial airgap flux comparison (FEMM vs Subdomain)

The airgap flux density maximum is reached when a stator teeth is facing an iron interpole, meaning when the permeance is maximal.
The subdomain model is very accurate and this enables to compute Maxwell forces along the airgap and determine electromagnetic forces.
To see the results for a IPMSM with a different winding pattern, click here.