Presentation and analysis of a novel hybrid stepping motor with stator-permanent-magnet structure

A new type of hybrid stepping motor (HSM) with permanent magnets mounted on the stator, namely the stator permanent magnet stepping motor (SPMSM), is put forward based on the structural topology of the conventional one with permanent magnet embedded in rotor. Schematic structures and superiorities of the novel SPMSM are firstly presented. Then the equivalent magnetic circuit of a 2-phase 8-pole SPMSM is built, and a field-circuit coupled method is adopted to compute its static and dynamic performance. A 2-D FEM is employed to verify the theoretical analysis and calculations. Moreover, an investigation on the performance comparison between the SPMSM and the HSM is carried out utilizing 3-D FEM. A prototyped 2-phase 8-pole SPMSM is manufactured and experimented, both the FEM analysis and experimental results show the proposed SPMSM can not only offer advantages of a traditional HSM, but also provide superiorities of a stator permanent magnet brushless machine.