Design and Analysis of a Consequent-Pole Flux Switching Permanent Magnet Machine With Flux-Concentrated Magnet for Torque Enhancement

• Published in: IEEE transactions on energy conversion 2024-12, Vol.39 (4), p.2468-2479
• Main Authors: Qiao, Zhenyang, Zhang, Yunpeng, Luo, Jian, Fu, Weinong, Bi, Yanding, Huang, Jiahui
• Format: Article
• Language: English
• Subjects: Consequent-pole; flux barrier; flux concentrated; flux-switching permanent magnet (FSPM) machine; Harmonic analysis; Magnetic cores; Magnetic flux leakage; Optimization; Rotors; Stator cores; Torque; torque density
• ISSN: 0885-8969; 1558-0059
• DOI: 10.1109/TEC.2024.3405001

Torque density is a crucial performance metric for flux-switching permanent magnet (FSPM) machines. However, the emergence of flux barriers tends to impede the magnetic field modulation effect, especially in machines with high pole ratios, ultimately impacting overall performance. To solve this issue, this paper proposed a consequent-pole FSPM machine with a flux-concentrated magnet design. The proposed machine adopts a 12-slot/13-pole configuration with a pole ratio of 13. To optimize the magnetic field concentration, the design integrates shortened clockwise tangentially magnetized PMs under an "h" core, positions radially magnetized PMs at the core's shoulders, and inserts counterclockwise tangential PMs into the slot openings. This arrangement effectively addresses the magnetic barrier issue, enhancing the magnetic field compactness within the machine. The operating principle of the proposed FSPM machine is analyzed using analytical computations and finite element analysis (FEA). The structural parameters are optimized for maximum average torque and efficiency. The proposed machine offers a 14.96% higher average torque and 2.1% higher efficiency than the existing FSPM machine with flux bridges at the same stator copper loss. A 640 W-rated prototype of the proposed machine was fabricated and tested, validating the simulation results and design accuracy through experiments.