VP22-01 A High-Performance Flux Modulated Arc Motors with Dual-PM Excitation
Creators: Xinxin Yang
Publisher: name: IEEE
Year: 2025

Flux modulated permanent magnet (PM) arc motors (FMPMAM) are widely used in tanks and astronomical telescopes due to the properties of high torque at low speed [1], [2]. Dual stator FMPMAM with single PMs (SPM-FMDSAM) is proposed to improve torque density by taking fully use of the internal space [3], [4]. To further improve the output torque, multi-PMs excited FMPMAM is proposed [5], [6]. However, it suffers from the low PM utilization and high cost with complex structure. To overcome the above limitations, a novel FMPMAM with dual PMs excitation (DPM-FMDSAM) is proposed and compared with a SPM-FMDSAM as shown in Figs. 1(a) and (b). By adopting dual PMs on the inner and outer stators with reversely magnetized PMs at corresponding positions, a superimposed flux is achieved as shown in Figs. 1(c) and (d), resulting in the increases of flux density and output torque. To validate the advantages of the proposed DPM-FMDSAM, the two motors with same sizes and turns in series per phase are optimized. The finite element analysis results at the rated current of 8 A are shown in Fig. 2. The back-electromotive force (EMF) of the proposed motor is obviously higher than that of SPM-FMDSAM leading to the higher average torque. Although the torque ripple of the proposal is larger compared with that of SPM-FMDSAM due to the structure of dual PMs excitation, it is low enough to be accepted. Moreover, the torque/PM ratio of the proposed motor (0.189Nm/cm3) is more than twice than that of SPM-FMDSAM (0.089Nm/cm3), which enhances PM utilization and reduces cost. Therefore, the proposed DPM-FMDSAM exhibits the properties of high torque, low ripple and high torque/PM ratio, making it an ideal choice for direct drive applications. More detailed analysis and results will be introduced in the full paper.References: [1] N. Tong, H. Liu, Y. Chen, et al, 2021 24th International Conference on Electrical Machines and Systems (ICEMS), Gyeongju, Korea, Republic of, 2021, pp. 1630-1635. [2] Z. Pan, S. Fang, H. Lin, et al, in IEEE Transactions on Magnetics, vol. 55, no. 7, pp. 1-10, July 2019, Art no. 8105610. [3] Z. Pan, J. Zhao, S. Fang et al, in IEEE Transactions on Transportation Electrification, vol. 9, no. 2, pp. 2509-2523, June 2023. [4] Y. Meng, S. Fang, Y. Zhu, et al, in IEEE Transactions on Applied Superconductivity, vol. 34, no. 8, pp. 1-5, Nov. 2024, Art no. 5204105. [5] N. Chen and S. Fang, 2023 IEEE International Conference on Applied Superconductivity and Electromagnetic Devices (ASEMD), Tianjin, China, 2023, pp. 1-2. [6] K. Wei, Z. Pan, J. Zhao, et al, 2023 26th International Conference on Electrical Machines and Systems (ICEMS), Zhuhai, China, 2023, pp. 1400-1403.
Flux modulated permanent magnet (PM) arc motors (FMPMAM) are widely used in tanks and astronomical telescopes due to the properties of high torque at low speed [1], [2]. Dual stator FMPMAM with single PMs (SPM-FMDSAM) is proposed to improve torque density by taking fully use of the internal space [3], [4]. To further improve the output torque, multi-PMs excited FMPMAM is proposed [5], [6]. However, it suffers from the low PM utilization and high cost with complex structure. To overcome the above limitations, a novel FMPMAM with dual PMs excitation (DPM-FMDSAM) is proposed and compared with a SPM-FMDSAM as shown in Figs. 1(a) and (b). By adopting dual PMs on the inner and outer stators with reversely magnetized PMs at corresponding positions, a superimposed flux is achieved as shown in Figs. 1(c) and (d), resulting in the increases of flux density and output torque. To validate the advantages of the proposed DPM-FMDSAM, the two motors with same sizes and turns in series per phase are optimized. The finite element analysis results at the rated current of 8 A are shown in Fig. 2. The back-electromotive force (EMF) of the proposed motor is obviously higher than that of SPM-FMDSAM leading to the higher average torque. Although the torque ripple of the proposal is larger compared with that of SPM-FMDSAM due to the structure of dual PMs excitation, it is low enough to be accepted. Moreover, the torque/PM ratio of the proposed motor (0.189Nm/cm3) is more than twice than that of SPM-FMDSAM (0.089Nm/cm3), which enhances PM utilization and reduces cost. Therefore, the proposed DPM-FMDSAM exhibits the properties of high torque, low ripple and high torque/PM ratio, making it an ideal choice for direct drive applications. More detailed analysis and results will be introduced in the full paper.References: [1] N. Tong, H. Liu, Y. Chen, et al, 2021 24th International Conference on Electrical Machines and Systems (ICEMS), Gyeongju, Korea, Republic of, 2021, pp. 1630-1635. [2] Z. Pan, S. Fang, H. Lin, et al, in IEEE Transactions on Magnetics, vol. 55, no. 7, pp. 1-10, July 2019, Art no. 8105610. [3] Z. Pan, J. Zhao, S. Fang et al, in IEEE Transactions on Transportation Electrification, vol. 9, no. 2, pp. 2509-2523, June 2023. [4] Y. Meng, S. Fang, Y. Zhu, et al, in IEEE Transactions on Applied Superconductivity, vol. 34, no. 8, pp. 1-5, Nov. 2024, Art no. 5204105. [5] N. Chen and S. Fang, 2023 IEEE International Conference on Applied Superconductivity and Electromagnetic Devices (ASEMD), Tianjin, China, 2023, pp. 1-2. [6] K. Wei, Z. Pan, J. Zhao, et al, 2023 26th International Conference on Electrical Machines and Systems (ICEMS), Zhuhai, China, 2023, pp. 1400-1403.