Design of a Novel PMSM Topology with the Same Number of Poles and Slots

This paper proposes a novel permanent magnet synchronous machine (PMSM) topology by combining few-pole multi-slot unit machines and multi-pole few-slot unit machines. Firstly, the design principles and winding arrangement of this type of machine are revealed based on the slot electromotive force star diagram. The calculation method of the winding factors of winding magnetomotive force (MMF) harmonics is summarized, and the principles of the composition of the topology are summarized based on the number of unit machines. Secondly, the performance of the machine, including no-load back electromotive force, electromagnetic torque, and electromagnetic losses, are analyzed through finite element analysis and theoretical calculations. Finally, the prototype of a 24-pole 24-slot PMSM with a combination of a 13-pole 12-slot unit machine and an 11- pole 12-slot unit machine is manufactured and compared with a 28-pole 24-slot conventional PMSM to verify its advantages in efficiency and torque density.