A Novel Axial Flux Interior Permanent Magnet Motor with High Torque Density

In this paper, a novel axial flux interior permanent magnet (AFIPM) motor is proposed. Two-layer spoke-type permanent magnets are adopted in this new disc-type motor. The magnetic circuit analysis is employed to compare air-gap flux densities of different spoke-type motors. The torque and torque densities of the proposed AFIPM motor and the conventional axial flux surface-mounted permanent magnet (AFSPM) motor are compared, too. It is shown that the proposed motor can achieve higher torque and torque density and the axial length ratio of the rotor to the whole machine is the key factor.