A Novel Hybrid Axial- and Radial-Flux Permanent Magnet Synchronous Machine

This paper focuses on the improvement of motor torque density and proposes a novel hybrid axial- and radial-flux permanent magnet synchronous machine (HARF-PMSM). The rotor of the proposed HARF-PMSM consists of five rotor sections and the stator is designed as a four-sided slot structure, surrounded by the five rotor sections, eventually forming a five-sided air-gap structure. This machine topology can realize the full utilization of the end windings and effectively improve motor space utilization, eventually increasing the torque density. In addition, the utilization of permanent magnets and stator windings has been improved. Furthermore, the heat dissipation capacity is enhanced, which means that the motor can withstand higher currents and output more torque. The machine topology of the proposed HARF-PMSM is first introduced and then its electromagnetic performance is demonstrated by the finite element analysis (FEA) results.