Principle Investigation and Performance Comparison of Consequent-Pole Switched Flux PM Machines
Hui Yang, Ya Li, Heyun Lin, Z. Q. Zhu, Shukang Lyu
Abstract
This article proposes a novel topology of consequent-pole switched flux permanent magnet (SFPM) machine with U-shaped permanent magnets (PMs) for torque improvement, which is attractive for traction applications. The proposed machine is geometrically derived from a conventional sandwiched SFPM machine by introducing airspace flux barriers and flat-type PMs. The proposed design can provide an effective circulating path for low-order field harmonics. This property is beneficial for torque capability enhancement. The machine topologies and operating principles are introduced first. Moreover, a magnetomotive force (MMF) permeance-based model for the proposed SFPM machines is employed to analytically reveal the underlying working mechanism. The electromagnetic characteristics of the two proposed SFPM machines are investigated by finite element (FE) analyses and compared with those of the conventional sandwiched SFPM machine. Finally, a 6-/13-pole SFPM machine with a U-shaped PM structure is manufactured and tested to experimentally validate the theoretical and FE analyses.