Comparison of Surface and Inset Bread-loaf PMSM with Parallel and Novel Magnetization Orientations for Electric VTOL/Aircraft Application

High-power-dense electric motors are essential for electric vertical take-off and landing (eVTOL) and electric aircraft applications. Surface mounted permanent magnet synchronous motor (SPMSM) and inset bread-loaf PMSM (IBLPMSM) are considered for this application since they have high power density. Field-weakening is desirable, especially for distributed electric propulsion (DEP) based eVTOL/aircraft. The problem of harmonics during the field-weakening operation is prominent in the motors where saliency exists. At high electrical loading due to saturation in stator, SPMSM shows better field-weakening capability compared to IBLPMSM. To improve the performance in both machines, novel magnetization polarities of the PM arc segments is proposed for both machines. This paper analyses and compares the performances of SPMSM and IBLPMSM especially in terms of power density and field-weakening capability.