Abstract:As for the traditional 4-pole 6-slot double-sided symmetrical long primary permanent magnet linear synchronous motor, under the condition of ensuring the electromagnetic thrust, an effective method to reduce the permanent magnet eddy current loss was proposed by adopting bilateral dislocation. The basic structure of the motor was introduced. The double-sided dislocation structure could completely eliminate the even number of armature harmonic magnetomotive force, thereby greatly reducing the permanent magnet eddy current loss. The finite element analysis (FEA) software was adopted to analyze the detent forces of symmetric and dislocation structures, the electromagnetic thrust and the secondary eddy current losses. The accuracy of the dislocation method was proved and the structure was optimized. At last, a prototype was developed, and its back-electromotive force (back-EMF), detent force and static thrust were measured through an experimental platform.
[1] Laithwaite E R.Adapting a linear induction motor for the acceleration of large masses to high velocities[J]. IEE Proceedings-Electric Power Applications, 1995, 142(4): 262-268. [2] Fair H D.The science and technology of electric launch[J]. IEEE Transactions on Magnetics, 2001, 37(1): 25-32. [3] 杜超, 孟大伟. 基于场路结合法的电磁弹射用新型永磁直线同步电机的研究[J]. 电机与控制学报, 2019, 23(9): 65-74. Du Chao, Meng Dawei.Investigation of permanent magnet linear synchronous motor for electromagnetic launch based on field-circuit combined method[J]. Electric Machines and Control, 2019, 23(9): 65-74. [4] 莫会成. 分数槽绕组与永磁无刷电动机[J]. 微电机, 2007, 40(11): 39-42. Mo Huicheng.Fractional-slot winding and PM brush- less motor[J]. Micromotors, 2007, 40(11): 39-42. [5] 谭建成. 三相无刷直流电动机分数槽集中绕组槽极数组合规律研究[J]. 微电机, 2007, 40(12): 72-77. Tan Jiancheng.Investigation on slot/pole number combinations for 3-phase BLDCM with concentrated windings[J]. Micromotors, 2007, 40(12): 72-77. [6] 陈益广, 潘玉玲, 贺鑫. 永磁同步电机分数槽集中绕组磁动势[J]. 电工技术学报, 2010, 25(10): 30-36. Chen Yiguang, Pan Yuling, He Xin.Magnetomotive force in permanent magnet synchronous machine with concentrated fractional-slot winding[J]. Transactions of China Electrotechnical Society, 2010, 25(10): 30-36. [7] 鲍晓华, 刘佶炜, 孙跃, 等. 低速大转矩永磁直驱电机研究综述与展望[J]. 电工技术学报, 2019, 34(6): 1148-1160. Bao Xiaohua, Liu Jiwei, Sun Yue, et al.Review and prospect of low-speed high-torque permanent magnet machines[J]. Transactions of China Electrotechnical Society, 2019, 34(6): 1148-1160. [8] Ishak D, Zhu Zhiqiang, Howe D.Eddy-current loss in the rotor magnets of permanent-magnet brushless machines having a fractional number of slots per pole[J]. IEEE Transactions on Magnetics, 2005, 41(9): 2462-2469. [9] 陈萍, 唐任远, 佟文明, 等. 高功率密度永磁同步电机永磁体涡流损耗分布规律及其影响[J]. 电工技术学报, 2015, 30(6): 1-9. Chen Ping, Tang Renyuan, Tong Wenming, et al.Permanent magnet eddy current loss and its influence of high power density permanent magnet synchronous motor[J]. Transactions of China Electrotechnical Society, 2015, 30(6): 1-9. [10] Takahashi I, Koganezawa T, Su Guijia, et al.A super high speed PM motor drive system by a quasi-current source inverter[J]. IEEE Transactions on Industry Applications, 1994, 30(3): 683-690. [11] Cho H W, Jang S M, Choi S K.A design approach to reduce rotor losses in high-speed permanent magnet machine for turbo-compressor[J]. IEEE Transactions on Magnetics, 2006, 42(10): 3521-3523. [12] Zhou Fengzheng, Shen Jianxin, Fei Weizhong, et al.Study of retaining sleeve and conductive shield and their influence on rotor loss in high-speed PM BLDC motors[J]. IEEE Transactions on Magnetics, 2006, 42(10): 3398-3400. [13] Yamazaki K, Fukushima Y.Effect of eddy-current loss reduction by magnet segmentation in synchronous motors with concentrated windings[J]. IEEE Transa- ctions on Industry Applications, 2011, 47(2): 779-788. [14] 孙权贵, 邓智泉, 张忠明. 基于齿槽效应的高速永磁电机转子涡流损耗解析计算[J]. 电工技术学报, 2018, 33(9): 1994-2004. Sun Quangui, Deng Zhiquan, Zhang Zhongming.Analytical calculation of rotor eddy current losses in high speed permanent magnet machines accounting for influence of slot opening[J]. Transactions of China Electrotechnical Society, 2018, 33(9): 1994-2004. [15] 张超, 陈丽香, 于慎波, 等. 不同保护型式下的高速表贴式永磁转子应力与温升分析[J]. 电工技术学报, 2019, 34(9): 1815-1824. Zhang Chao, Chen Lixiang, Yu Shenbo, et al.Stress and temperature rise of high speed surface-mounted permanent magnet rotor with different protection types[J]. Transactions of China Electrotechnical Society, 2019, 34(9): 1815-1824. [16] 朱龙飞, 祝天利, 于慎波, 等. 一种气隙磁导谐波引起的永磁体涡流损耗的解析计算方法[J]. 电工技术学报, 2020, 24(5): 10-16. Zhu Longfei, Zhu Tianli, Yu Shenbo, et al.Analytical approach for calculation of eddy current losses in magnets caused by permeance harmonics in air gap[J]. Transactions of China Electrotechnical Society, 2020, 24(5): 10-16. [17] Sun Afang, Li Jian, Qu Ronghai, et al.Effect of multilayer windings on rotor losses of interior permanent magnet generator with fractional-slot concentrated windings[J]. IEEE Transactions on Magnetics, 2014, 50(11): 1-4. [18] Dajaku G, Gerling D.Low costs and high-efficiency electric machines[C]//2nd International Electric Drives Production Conference, Nuremberg, Germany, 2013: 1-7. [19] Dajaku G, Xie Wei, Gerling D.Reduction of low space harmonics for the fractional slot concentrated windings using a novel stator design[J]. IEEE Transa- ctions on Magnetics, 2014, 50(5): 1-12. [20] 徐广人, 唐任远, 安忠良. 永磁同步电动机气隙磁场分析[J]. 沈阳电力高等专科学校学报, 2001, 3(2): 1-4. Xu Guangren, Tang Renyuan, An Zhongliang.The analysis of airgap magnetic field of permanent magnet synchronous motor[J]. Journal of Shenyang Electric Power Institute, 2001, 3(2): 1-4.