Design and Analysis of a Multi-unit Distributed Permanent Magnet Arc Motor Having Double-Sided Permanent Magnet Excitations

As a special linear motor, the permanent magnet arc motor (PMAM) has attracted increasing attention in some special low speed high torque applications. The traditional PMAM only utilizes single-sided permanent magnet (PM) excitation to produce torque, which leads to limited torque performance. To solve this issue, a multi-unit distributed double-sided PM excited PMAM (DPM-PMAM) is proposed in this paper. The key of the proposed DPM-PMAM is to employ some PMs on the stator and rotor-sides and to design multi-unit distributed structure. First, the motor configuration of the proposed DPM-PMAM is introduced. Besides, the operation principle is analyzed based on the field modulation theory. Subsequently, the optimization design of the DPM-PMAM is conducted based on three-step strategy. Based on the optimal design, the motor performance of the proposed DPM-PMAM is evaluated by the comparisons with other three PMAMs. Finally, a prototype of the DPM-PMAM is manufactured, some experiments are performed for the finite element validation.