Experimental verification of core and magnet losses in a concentrated wound IPM machine with V-shaped magnets used in field weakening applications

It is well known that concentrated windings results in an increase of airgap flux harmonics, which leads to additional losses. In the wider field weakening regions, the machine yields a non-linear increase in losses due to the frequency-squared dependence of eddy current loss. This paper compares the higher frequency losses in the stator core, rotor core and magnets with different rotor magnet configurations and lamination thicknesses. Known loss reduction techniques are investigated and implemented. Losses are predicted by 2D and 3D finite element analysis. A 1kW concentrated wound IPM machine prototype with V-shaped sintered neodymium magnets has been built and the experiment results are used to validate modeled losses.