Due to the advantages of high reliability, low cost and simple structure, permanent magnet linear synchronous motor(PMLSM) have been increasingly used in high-precision industrial servo applications. However, the lack of mechanical transmission in the structure makes it more susceptible to uncertainties such as parameter variations and load disturbance. To solve the above problem, a fractional order boundary layer nonsingular fast terminal sliding mode control(FO-NFTSMC) strategy is proposed.
Firstly, the dynamic model of PMLSM containing uncertainties is established. Then, the nonsingular fast terminal sliding mode control (NFTSMC) method is used to suppress the influence of uncertainties on the system, which ensures that the tracking error converges to zero in a finite time and avoids the singularity problem. In addition, the Riemann-Liouville fractional order differential definition and the boundary layer technique are combined to realize a new fractional order differential boundary layer control. The fractional order boundary layer has the output characteristics of the integer boundary layer and can also change the output value with the direction of change of the state trajectory, solving the contradiction between “Weak chattering” and “fast convergence” in the traditional integer order boundary layer control.
To highlight the superiority of the proposed method, the contrast experiments based on FO-NFTSMC method and IO-NFTSMC method are carried out on a linear motor system. When tracking a given step command, the actual trajectory based on the FO-NFTSMC deviates less from the given tracking trajectory and the steady-state error remains around 5 μm, while the deviation value of the IO-NFTSMC strategy is larger and the steady-state error remains around 10 μm. Therefore, the system based on the FO-NFTSMC has better tracking performance and weaker chattering. To further investigate the robustness of the PMLSM control system as affected by changes in motor mass and friction, a linear motor mounted with a 2 kg payload is allowed to track a given sine signal. The position tracking error of FO-NFTSMC has a smaller value compared to IO-NFTSMC, with a reduction of about 60%. In addition, the IO-NFTSMC strategy responds slower at the beginning of the system response, reaching steady state in about 0.1s, while the FO-NFTSMC ensures the convergence time of the system. Also, the load disturbance of 5N is suddenly added to the PMLSM system at nominal condition to verify the anti-interference ability of the system. The experimental result show that the error curves of both control strategies fluctuate significantly, with the fluctuation amplitude of FO-NFTSMC being smaller and remaining within 10 μm. While the tracking error curve of IO-NFTSMC strategy has a larger fluctuation amplitude, with the maximum magnitude reaching about 30μm. Finally, to verify the effect of different order of fractional-order boundary layer control on the system performance, an additional set of experiments were done to change only the fractional order condition, and experimental results showed that the 0.2 order-based control system has better dynamic performance.
The following conclusions can be drawn from the experimental analysis: 1) Compared with the IO-NFTSMC method, the FO-NFTSMC method improves the position tracking accuracy and robustness performance of the PMLSM system.2) Using the fractional order boundary layer control, the sliding mode chattering is reduced and the dynamic performance of PMLSM servo system is improved.3) Fractional order control systems have a wider range of parameter selection than integer-order control systems.
赵鑫宇, 王丽梅. 永磁直线同步电机分数阶微分型边界层终端滑模控制[J]. 电工技术学报, 0, (): 1-1.
Zhao Xinyu, Wang Limei. Fractional Order Differential Boundary Layer Terminal Sliding Mode Control for Permanent Magnet Linear Synchronous Motor. Transactions of China Electrotechnical Society, 0, (): 1-1.
[1] 张春雷, 张辉, 叶佩青, 等. 两相圆筒型永磁同步直线电机无传感算法[J]. 电工技术学报, 2019, 34(23): 4901-4908.
Zhang Chunlei, Zhang Hui, Ye Peiqing, et al.Research on sensorless algorithm of two-phase tubular permanent magnet synchronous linear motor[J]. Transactions of China Electrotechnical Society, 2019, 34(23): 4901-4908.
[2] 李雄松, 崔鹤松, 胡纯福, 等. 平板型永磁直线同步电机推力特性的优化设计[J]. 电工技术学报, 2021, 36(5): 916-923.
Li Xiongsong, Cui Hesong, Hu Chunfu, et al.Optimal design of thrust characteristics of flat-type permanent magnet linear synchronous motor[J]. Transactions of China Electrotechnical Society, 2021, 36(5): 916-923.
[3] 张康, 王丽梅. 基于反馈线性化的永磁直线同步电机自适应动态滑模控制[J]. 电工技术学报, 2021, 36(19): 4016-4024.
Zhang Kang, Wang Limei.Adaptive dynamic sliding mode control of permanent magnet linear synchronous motor based on feedback linearization[J]. Transactions of China Electrotechnical Society, 2021, 36(19): 4016-4024.
[4] 孙宜标, 仲原, 刘春芳. 基于LMI的直线伺服滑模位移跟踪控制[J]. 电工技术学报, 2019, 34(1): 33-40.
Sun Yibiao, Zhong Yuan, Liu Chunfang.LMI-based sliding mode displacement tracking control for permanent magnet linear synchronous motor[J]. Transactions of China Electrotechnical Society, 2019, 34(1): 33-40.
[5] Li Longfei, Xiao Jie, Zhao Yun, et al.Robust position anti-interference control for PMSM servo system with uncertain disturbance[J]. CES Transactions on Electrical Machines and Systems, 2020, 4(2): 151-160.
[6] Kao Yonggui,Wang Changhong.H∞ sliding mode control for uncertain neutral-type stochastic systems with Markovian jumping parameters[J]. Information Sciences,2015,314(3):200-211.
[7] 穆朝絮, 余星火, 孙长银. 非奇异终端滑模控制系统相轨迹和暂态分析[J]. 自动化学报, 2013, 39(6): 902-908.
Mu Chaoxu, Yu Xinghuo, Sun Changyin.Phase trajectory and transient analysis for nonsingular terminal sliding mode control systems[J]. Acta Automatica Sinica, 2013, 39(6): 902-908.
[8] Wang Yaonan, Zhang Xizheng, Yuan Xiaofang, et al.Position-sensorless hybrid sliding-mode control of electric vehicles with brushless DC motor[J]. IEEE Transactions on Vehicular Technology, 2011, 60(2): 421-432.
[9] 张贝贝, 赵东亚, 高守礼, 等. 自适应边界层非奇异快速终端滑模控制[J]. 控制工程, 2019, 26(4): 717-723.
Zhang Beibei, Zhao Dongya, Gao Shouli, et al.A novel nonsingular fast terminal sliding mode control with adaptive boundary layer[J]. Control Engineering of China, 2019, 26(4): 717-723.
[10] Ghaebi Panah P, Ataei M, Mirzaeian B, et al.A robust adaptive sliding mode control for PMLSM with variable velocity profile over wide range[J]. Research Journal of Applied Sciences, Engineering and Technology, 2015, 10(9): 997-1006.
[11] 张月玲, 党选举. 基于死区迟滞函数的永磁同步直线电机滑模控制[J]. 中国电机工程学报, 2011, 31(3): 67-74.
Zhang Yueling, Dang Xuanju.Sliding mode control based on dead-zone hysteresis function for PMLSM[J]. Proceedings of the CSEE, 2011, 31(3): 67-74.
[12] 赵希梅, 赵久威. 永磁直线同步电机的互补滑模变结构控制[J]. 中国电机工程学报, 2015, 35(10): 2552-2557.
Zhao Ximei, Zhao Jiuwei.Complementary sliding mode variable structure control for permanent magnet linear synchronous motor[J]. Proceedings of the CSEE, 2015, 35(10): 2552-2557.
[13] Manabe S.The non-integer integral and its application to control systems[J]. Electrotechnical Journal of Japan,1961,6(3-4):83-87.
[14] Oustaloup A, Moreau X, Nouillant M.From fractal robustness to non-integer approach in vibration insulation: the CRONE suspension[C]//Proceedings of the 36th IEEE Conference on Decision and Control, San Diego, CA, USA, 2002: 4979-4984.
[15] 张碧陶, 皮佑国. 基于分数阶滑模控制技术的永磁同步电机控制[J]. 控制理论与应用, 2012, 29(9): 1193-1197.
Zhang Bitao, Pi Youguo.Fractional order sliding-mode control for permanent magnet synchronous motor[J]. Control Theory & Applications, 2012, 29(9): 1193-1197.
[16] Chen S Y, Chiang H H, Liu T S, et al.Precision motion control of permanent magnet linear synchronous motors using adaptive fuzzy fractional-order sliding-mode control[J]. IEEE/ASME Transactions on Mechatronics, 2019, 24(2): 741-752.
[17] Yin Chun, Huang Xuegang, Chen Yangquan, et al.Fractional-order exponential switching technique to enhance sliding mode control[J]. Applied Mathematical Modelling, 2017, 44: 705-726.
[18] 孙宜标, 杨雪, 夏加宽. 采用鲁棒微分器的永磁直线同步电机二阶滑模控制[J]. 中国电机工程学报, 2007, 27(33): 6-10.
Sun Yibiao, Yang Xue, Xia Jiakuan.Second order sliding mode control for PMLSM using robust differentiator[J]. Proceedings of the CSEE, 2007, 27(33): 6-10.
[19] Zhang Fengrong, Li Changpin.Remarks on the initialization of Caputo derivative[C]//Proceedings of 2012 IEEE/ASME 8th IEEE/ASME International Conference on Mechatronic and Embedded Systems and Applications, Suzhou, China, 2012: 325-329.