VP22-07 An Axial Parallel Memory Machine with DC Bias Adjustment Flux Capability
Creators: Ling Qin
Publisher: name: IEEE
Year: 2025

I.Introduction The traditional stator PM memory machines (MM) are basically geometrically characterized by a re/demagnetization winding surrounded by the low coercive force (LCF) PM [1-3]. This type of winding is applied the pulse current to adjust the magnetization state of LCF PM. However, these windings can only be used in the re/demagnetization operation, but do not have other functions in normal working condition. In order to improve the space utilization, the MM with DC bias adjustment flux capability is proposed [4]. However, the working point of LCF PM is still easily affected by high CF (HCF) PM, leading to low overload capability. Herein, a new axial parallel MM with DC bias adjustment flux capability (DCB-AXMM) is proposed. The DCB-AXMM utilizes an integrated winding to generate DC bias magnetizing current pulse to change the MS of the LCF PMs. II. Topology and Electromagnetic Performances Fig. 1 shows the topology of the DCB-AXMM. The proposed machine consists of three sub-machines, i.e., Part I, Part II and Part III, respectively. They share the same stator/rotor combinations. The PMs in the Parts I and III sub-machines utilize the N42SH (HCF PM), which are magnetized in the opposite direction. The PMs in the Parts II and III sub-machines are magnetized in the same direction and the PM in Part II are AlNiCo9 (LCF PM). The rotors of Parts II and III sub-machines have no offset, while the rotor of Part I sub-machine is shifted 45° mechanical angle compared to that of the Part II and Part III sub-machines. The integrated windings are wrapped around the stator poles. Fig. 2(a) shows the no-load back-EMF at flux-enhanced(FM) and zero-magnetization (ZM) levels. The total harmonic distortion (THD) of back-EMF in different magnetization levels are 12.4% and 8.9%, respectively. Fig. 2(b) shows the steady-state torque under different magnetization levels. As shown in Fig. 2(b), the torque profiles under different MSs experience a clear vibration which indicates that the output torque can be flexibly adjusted by applying different magnitudes of zero-sequence magnetization current pulse. The details will be addressed in the full paper.References: [1]W. Li, K. T. Chau, Y. Gong, J. Z. Jiang and F. Li. A new flux-mnemonic dual-magnet brushless machine. IEEE Trans. Magn., vol. 47, no.10, pp:4223-4226, 2011. [2]F. Li, K. T. Chau, C. Liu and C. Qiu. “New approach for pole-changing with dual-memory machine”. IEEE Trans. Appl. Supercon., 2014, 24(3):1-4, Art no. 0501504. [3]H. Yang, H. Lin, S. Fang, Z. Q. Zhu and Y. Huang. “Flux-regulatable characteristics analysis of a novel switched-flux surface-mounted PM memory machine”. IEEE Trans. Magn., vol. 50, no.11, Nov. 2014. [4]L. Qin, H. Yang, S. Fang, H. Lin, Z. Pan and Y. Meng, "Design and Investigation of a hybrid stator pole memory machine with DC bias magnetization capability". IEEE Trans. Appl. Supercon., vol. 31, no. 8, pp. 1-5, Nov. 2021, Art no. 5205005.
I.Introduction The traditional stator PM memory machines (MM) are basically geometrically characterized by a re/demagnetization winding surrounded by the low coercive force (LCF) PM [1-3]. This type of winding is applied the pulse current to adjust the magnetization state of LCF PM. However, these windings can only be used in the re/demagnetization operation, but do not have other functions in normal working condition. In order to improve the space utilization, the MM with DC bias adjustment flux capability is proposed [4]. However, the working point of LCF PM is still easily affected by high CF (HCF) PM, leading to low overload capability. Herein, a new axial parallel MM with DC bias adjustment flux capability (DCB-AXMM) is proposed. The DCB-AXMM utilizes an integrated winding to generate DC bias magnetizing current pulse to change the MS of the LCF PMs. II. Topology and Electromagnetic Performances Fig. 1 shows the topology of the DCB-AXMM. The proposed machine consists of three sub-machines, i.e., Part I, Part II and Part III, respectively. They share the same stator/rotor combinations. The PMs in the Parts I and III sub-machines utilize the N42SH (HCF PM), which are magnetized in the opposite direction. The PMs in the Parts II and III sub-machines are magnetized in the same direction and the PM in Part II are AlNiCo9 (LCF PM). The rotors of Parts II and III sub-machines have no offset, while the rotor of Part I sub-machine is shifted 45° mechanical angle compared to that of the Part II and Part III sub-machines. The integrated windings are wrapped around the stator poles. Fig. 2(a) shows the no-load back-EMF at flux-enhanced(FM) and zero-magnetization (ZM) levels. The total harmonic distortion (THD) of back-EMF in different magnetization levels are 12.4% and 8.9%, respectively. Fig. 2(b) shows the steady-state torque under different magnetization levels. As shown in Fig. 2(b), the torque profiles under different MSs experience a clear vibration which indicates that the output torque can be flexibly adjusted by applying different magnitudes of zero-sequence magnetization current pulse. The details will be addressed in the full paper.References: [1]W. Li, K. T. Chau, Y. Gong, J. Z. Jiang and F. Li. A new flux-mnemonic dual-magnet brushless machine. IEEE Trans. Magn., vol. 47, no.10, pp:4223-4226, 2011. [2]F. Li, K. T. Chau, C. Liu and C. Qiu. “New approach for pole-changing with dual-memory machine”. IEEE Trans. Appl. Supercon., 2014, 24(3):1-4, Art no. 0501504. [3]H. Yang, H. Lin, S. Fang, Z. Q. Zhu and Y. Huang. “Flux-regulatable characteristics analysis of a novel switched-flux surface-mounted PM memory machine”. IEEE Trans. Magn., vol. 50, no.11, Nov. 2014. [4]L. Qin, H. Yang, S. Fang, H. Lin, Z. Pan and Y. Meng, "Design and Investigation of a hybrid stator pole memory machine with DC bias magnetization capability". IEEE Trans. Appl. Supercon., vol. 31, no. 8, pp. 1-5, Nov. 2021, Art no. 5205005.