Design and Topology Development of a New Split-Tooth Permanent Magnet Arc Motor With Dual Excitations

This article proposes the design and topology development of a novel split-tooth permanent magnet arc motor with dual excitation (STPMAM-DE). The proposed motor addresses the limited light-load torque capability of conventional slot-PM arc motors by integrating additional permanent magnets on the stator teeth, combining the advantages of split-tooth slot-PM and flux-reversal PM configurations. Through finite element analysis (FEA), the electromagnetic performance of both conventional and split-tooth PM arc motors is evaluated, leading to the development of the STPMAM-DE topology. The operating principle and torque generation mechanism are analyzed, with particular attention to the magnetization configuration of the PMs to enhance the fundamental magnetomotive force and suppress the 3rd harmonic, thereby improving torque output. Comparative FEA results demonstrate that the STPMAM-DE offers higher torque density and improved overload capability up to 150% of the rated torque compared with the benchmark designs. Experimental validation via a prototype confirms the enhanced torque performance and operational efficiency of the motor, supporting the feasibility and advantages of the proposed dual-excitation structure.