Design and Analysis of a Novel Axial Flux Stator Staggered Pole Permanent Magnet Machine

The axial flux permanent magnet (PM) (AFPM) machine features the advantages of short axial length, small size, simple and compact structure, high power/torque density, and so on. In this paper, an axial field stator stagger pole PM (AFSSPPM) machine, which inherits the characteristics of AFPM machines and has improved power/torque density, is proposed and investigated. Firstly, the topology and operating principle of the machine is researched in detail. Secondly, the magnetomotive force (MMF), rotor permeance and armature reaction MMF models are established. According to the airgap field modulation theory, the field modulation mechanism in airgap of the machine is revealed, which is helpful for creating a theoretical foundation of machine design and performance analysis. Finally, the power-size and output torque equations are deduced and the major parameters are obtained. Then, the electromagnetic performances are examined. The results indicate that the proposed AFSSPPM machine has superior properties in terms of flux-linkage, back-EMF and torque capability. Meanwhile, the enhanced power density, powerful torque output capability and high PM utilization are achieved.