Comparative Study of Axial Flux Permanent Magnet Machines With Different Segmented Stator Cores

The axial flux permanent magnet (AFPM) machine with segmented stator cores can effectively improve its torque density and efficiency. In this paper, the segmented stator core with combined lamination is proposed. Different from segmented stator cores with soft magnetic composite (SMC) and radial lamination, this segmented stator core with combined lamination consists of tangential laminated shoes and the radial laminated bar. The electromagnetic performances of AFPM machines with the above three segmented stator cores for in-wheel drive applications are calculated and compared such as no-load air gap flux density, back electromagnetic force (EMF), iron losses, efficiency, and torque characteristics. It is concluded that compared with SMC, the AFPM machine of the segmented stator core with combined lamination has prominent advantages in terms of efficiency and torque density, although its flux density harmonic components are slightly sacrificed.