Design, Analysis, and Comparison of A Spoke-Type Hybrid Permanent Magnet Synchronous Motor for Gearless Elevator Application

High cost, inconsistent supply, and adverse environmental impacts limit the wider deployment of rare-earth-based permanent magnet synchronous motors in gearless elevator applications. To address this challenge, this paper presents a new spoke-type hybrid permanent magnet synchronous motor (ST-H-PMSM). The special feature of the motor is the artful utilization of ferrite PM to reduce the consumption of rare-earth PM and boost the airgap flux density. The proposed motor is designed for a gearless elevator system of a mid-rise building, and its design variables are optimized via the finite element method (FEM). For a fair comparison, the electromagnetic performances of the ST-H-PMSM are compared to those of a surface-mounted permanent magnet synchronous motor (SPMSM) developed with the same overall dimensions, slot-pole combination, number of turns per phase, and input current. The results reveal that the ST-H-PMSM has better torque characteristics and rare-earth PM usage efficiency compared to the SPMSM. Moreover, the efficiency and power factor of the new design are comparable to its counterpart.