Abstract：Traditional I-f control for sensorless control of the permanent magnet synchronous motor (PMSM) suffers from poor damping and disturbance rejection, which lead to large speed oscillations at motor startup and long transition time when switching to close-loop control. It is unfavorable for multi-rotor unmanned aerial vehicles and electric vertical take-off vehicles. According to the differentiation of d-axis voltage and transition strategy, this paper proposes an improved I-f control strategy with frequency compensation to increase damping and improve disturbance rejection of the I-f control based on decoupling current dynamics and angle dynamics. Speed oscillations at motor startup are suppressed significantly, and a fast transition from I-f control to closed-loop control is achieved smoothly with less mechanical dynamics. Firstly, a small-signal perturbation model of the I-f control is deduced with detailed analyses of its damping characteristics. To increase damping and suppress speed oscillations, differentiation of the open-loop d-axis voltage is used to compensate for the open-loop frequency. Secondly, to improve the load disturbance rejection when switching to closed-loop control, the angle of the reference current vector is rotated via Park transformation. In contrast, the open loop angle is increased to gradually approach the real rotor angle obtained by the angle observer. Since the reference current vector is stationary relative to the real rotor angle during this transition process, no mechanical dynamics are generated. This transition can even be done at zero angle error between the real rotor coordinate and the open-loop coordinate, which indicates no current and angle dynamics at the switching instant. The amplitude of the reference current vector is kept unchanged throughout the whole I-f control. Therefore, the load disturbance is effectively rejected, even during the transition process. Finally, after switching to closed-loop control successfully, the d-axis current is decreased to 0 according to a certain trajectory, and normal closed-loop control takes over. Two experiments demonstrate the improvement of system damping and load disturbance rejection. In the first experiment, the proposed strategy is compared with the traditional I-f control and the perturbation of active power in literature. The experimental results show that under traditional I-f control, significant speed oscillations occur during the starting phase, and the peak-to-peak value of speed oscillations is about 80 r/min. With perturbation of active power, speed oscillations rapidly decay in 0.1 seconds, and the peak-to-peak value of speed drops to about 10 r/min in the steady state. The motor attenuates speed oscillations fast, and the peak-to-peak value of speed drops to about 5 r/min in the steady state. The second experiment compares the proposed transition strategy and the strategy by reducing the q-axis current in the literature. The experimental results show that reducing the q-axis current generates large mechanical dynamics at the transition stage under sudden load disturbances. The speed decreases by about 260 r/min at the load disturbance of 0.064 N·m, and the motor is out of control at the load disturbance of 0.16 N·m. Mechanical dynamics are much smaller using the proposed method. The speed decreases by about 40 r/min at the load disturbance of 0.064 N·m, and the motor can still maintain normal operation at the load disturbance of 0.512 N·m. The proposed improved I-f control strategy has better damping effect on speed oscillations and can transition to closed-loop control with strong rejection of load disturbances.
李福, 陈双琛, 兰志勇, 蒋云泽, 赵怡妮. 基于改进型I-f控制的永磁同步电机无位置控制[J]. 电工技术学报, 2025, 40(12): 3895-3904.
Li Fu, Chen Shuangchen, Lan Zhiyong, Jiang Yunze, Zhao Yini. Sensorless Control of Permanent Magnet Synchronous Motor Based on Improved I-f Control. Transactions of China Electrotechnical Society, 2025, 40(12): 3895-3904.
[1] 肖鑫, 孙乐, 甘辉. 基于抗扰扩展卡尔曼滤波的摇臂伺服控制[J]. 中国电机工程学报, 2023, 43(20): 8102-8114. Xiao Xin, Sun Le, Gan Hui.Swing servo control based on extended Kalman filter with disturbance-rejection[J]. Proceedings of the CSEE, 2023, 43(20): 8102-8114. [2] 兰志勇, 李延昊, 罗杰, 等. 一种自适应扩展卡尔曼滤波的永磁同步电机无位置传感器矢量控制[J]. 电机与控制学报, 2024, 28(3): 141-148. Lan Zhiyong, Li Yanhao, Luo Jie, et al.Sensorless vector control of permanent magnet synchronous motor based on adaptive extended Kalman filter[J]. Electric Machines and Control, 2024, 28(3): 141-148. [3] 朱国宇, 安兴科, 诸德宏, 等. 基于改进自适应超螺旋观测器的永磁同步电机无位置控制[J]. 电气工程学报, 2023, 18(4): 84-95. Zhu Guoyu, An Xingke, Zhu Dehong, et al.Position sensorless control for permanent magnet synchronous motor using improved adaptive super twisting observer[J]. Journal of Electrical Engineering, 2023, 18(4): 84-95. [4] 吕德刚, 刘站卓, 徐翔. 带负载扰动补偿的永磁同步电机改进MRAS观测器控制[J]. 电机与控制学报, 2023, 27(6): 46-54. Lü Degang,Liu Zhanzhuo, Xu Xiang.Improved MRAS observer control of permanent magnet syn-chronous motors with load disturbance com-pensation[J]. Electric Machines and Control, 2023, 27(6): 46-54. [5] 孙庆国, 朱晓磊, 牛峰, 等. 基于改进型积分滑模观测器的PMSM无位置传感器控制[J]. 中国电机工程学报, 2024, 44(8): 3269-3278. Sun Qingguo, Zhu Xiaolei, Niu Feng, et al.Sensorless control of permanent magnet synchronous motor based on improved integral sliding mode observer[J]. Proceedings of the CSEE, 2024, 44(8): 3269-3278. [6] 赵文祥, 宋世昌, 周书文, 等. 改进滑模观测器的电流源逆变器驱动PMSM无位置传感器控制[J]. 电工技术学报, 2024, 39(4): 987-995. Zhao Wengxiang, Song Shichang, Zhou Shuwen, et al.Sensorless control of current source inverter driven PMSM with improved sliding mode observer[J]. Transactions of China Electrotechnical Society, 2024, 39(4): 987-995. [7] Wang Gaolin, Valla M, Solsona J.Position sensorless permanent magnet synchronous machine drives-a review[J]. IEEE Transactions on Industrial Electro-nics, 2020, 67(7): 5830-5842. [8] 徐奇伟, 熊德鑫, 陈杨明, 等. 基于新型高频纹波电流补偿方法的内置式永磁同步电机无传感器控制[J]. 电工技术学报, 2023, 38(3): 680-691. Xu Qiwei, Xiong Dexin, Chen Yangming, et al.Research on sensorless control strategy of IPMSM based on new high frequency ripple current com-pensation method[J]. Transactions of China Elec-trotechnical Society, 2023, 38(3): 680-691. [9] 张彦平, 尹忠刚, 苏明, 等. 基于共振扩张状态观测器的内置式永磁同步电机统一全速域无位置传感器控制[J]. 电工技术学报, 2023, 38(22): 6070-6081. Zhang Yanping, Yin Zhonggang, Su Ming, et al.Unified full speed sensorless control of interior permanent magnet synchronous motor based on resonance extended state observer[J]. Transactions of China Electrotechnical Society, 2023, 38(22): 6070-6081. [10] 朱小芬, 黄科元, 黄守道. 一种稳定的高速永磁同步电机V/F控制方法[J]. 电力电子技术, 2018, 52(7): 28-32. Zhu Xiaofen, Huang Keyuan, Huang Shoudao.A stable V/F control method of high-speed permanent magnet synchronous motor[J]. Power Electronics, 2018, 52(7): 28-32. [11] Nair S V, Hatua K, Prasad N V P R D, et al. A quick I-f starting of PMSM drive with pole slipping prevention and reduced speed oscillations[J]. IEEE Transactions on Industrial Electronics, 2021, 68(8): 6650-6661. [12] Chen Dunzhi, Lu Kaiyuan, Wang Dong, et al.I-F control with zero D-axis current operation for surface-mounted permanent magnet synchronous machine drives[J]. IEEE Transactions on Power Electronics, 2023, 38(6): 7504-7513. [13] Chen Dunzhi, Lu Kaiyuan, Wang Dong.An I-f startup method with compensation loops for PMSM with smooth transition[J]. IEEJ Journal of Industry Applications, 2020, 9(3): 263-270. [14] 刘计龙, 肖飞, 麦志勤, 等. IF控制结合滑模观测器的永磁同步电机无位置传感器复合控制策略[J]. 电工技术学报, 2018, 33(4): 919-929. Liu Jilong, Xiao Fei, Mai Zhiqin, et al.Hybrid position-sensorless control scheme for PMSM based on combination of IF control and sliding mode observer[J]. Transactions of China Electrotechnical Society, 2018, 33(4): 919-929. [15] 刘计龙, 肖飞, 麦志勤, 等. 基于双dq空间的永磁同步电机无位置传感器起动策略[J]. 电工技术学报, 2018, 33(12): 2676-2684. Liu Jilong, Xiao Fei, Mai Zhiqin, et al.Position-sensorless startup strategy for permanent magnet synchronous motor based on double dq space[J]. Transactions of China Electrotechnical Society, 2018, 33(12): 2676-2684. [16] 付康壮, 刘计龙, 麦志勤, 等. 改进型IF控制结合有效磁链法的永磁同步电机全速域无位置传感器控制策略[J]. 电工技术学报, 2022, 37(22): 5704-5716. Fu Kangzhuang, Liu Jilong, Mai Zhiqin, et al.A full-speed domain sensorless control strategy for permanent magnet synchronous motor based on improved IF control and effective flux method[J]. Transactions of China Electrotechnical Society, 2022, 37(22): 5704-5716. [17] Tang Qipeng, Chen Duxin, He Xiangning.Integration of improved flux linkage observer and I-f starting method for wide-speed-range sensorless SPMSM drives[J]. IEEE Transactions on Power Electronics, 2020, 35(8): 8374-8383. [18] Xu Yao, Lin Cheng, Xing Jilei, et al.I-f starting rapid and smooth transition method of full-speed sensorless control for low current harmonic ultra-high-speed PMSM[C]//2022 IEEE Applied Power Electronics Conference and Exposition (APEC), Houston, TX, USA, 2022: 1820-1826. [19] Nair S V, Hatua K, Durga Prasad N V P R, et al. Quick and seamless transition method for I-f to sensorless vector control changeover and on-the-fly start of PMSM drives[J]. IET Electric Power Applications, 2020, 14(11): 2231-2242. [20] Li Qidong, Wang Xudong, Jiang Jia, et al.Sensorless control for surface mounted PM machine with a high inertial load[J]. CES Transactions on Electrical Machines and Systems, 2018, 2(1): 116-122. [21] Fatu M, Teodorescu R, Boldea I, et al.I-F starting method with smooth transition to EMF based motion-sensorless vector control of PM synchronous motor/generator[C]//2008 IEEE Power Electronics Specialists Conference, Rhodes, Greece, 2008: 1481-1487. [22] Wang Zihui, Lu Kaiyuan, Blaabjerg F.A simple startup strategy based on current regulation for back-EMF-based sensorless control of PMSM[J]. IEEE Transactions on Power Electronics, 2012, 27(8): 3817-3825. [23] Xing Jilei, Qin Zhidong, Lin Cheng, et al.Research on startup process for sensorless control of PMSMs based on I-f method combined with an adaptive compensator[J]. IEEE Access, 2020, 8: 70812-70821.
2025, Vol. 40 
