A Position Sensorless Control Strategy for Brushless DC Motor Based on the Back-Electromotive Force Function
Chen Wei1,2, Liu Huimin1, Gu Xin2, Li Xinmin2, Shi Tingna1
1. School of Electrical and Information Engineering Tianjin University Tianjin 300072 China; 2.Tianjin Engineering Center of Electric Machine System Design and Control Tianjin Polytechnic University Tianjin 300387 China
Abstract：The floating phase of brushless DC motor (BLDCM) has longer commutation freewheeling time under high speed and heavy load conditions. Sometimes the freewheeling interval even exceeds 30 electrical degrees, which causes the conventional methods fail to detect the back-(electromotive force) EMF zero-crossing signal, resulting in commutation failure. A novel sensorless control strategy for the brushless DC motor is proposed in this paper. By analyzing the back EMF and back-EMF slope of the floating phase, a back-EMF function independent of the motor speed is constructed, and its threshold directly corresponds to the commutation signal. Therefore, the proposed strategy does not need the back-EMF zero-crossing signal, and can control the stable operation of the motor when the commutation freewheeling time is long. In addition, since no low-pass filter is adopted, the strategy also avoids the phase shift problem caused by filtering. The experimental results verify the effectiveness and feasibility of the proposed strategy.
陈炜, 刘会民, 谷鑫, 李新旻, 史婷娜. 基于反电动势函数的无刷直流电机无位置传感器控制方法[J]. 电工技术学报, 2019, 34(22): 4661-4669.
Chen Wei, Liu Huimin, Gu Xin, Li Xinmin, Shi Tingna. A Position Sensorless Control Strategy for Brushless DC Motor Based on the Back-Electromotive Force Function. Transactions of China Electrotechnical Society, 2019, 34(22): 4661-4669.
[1] 李新旻, 夏长亮, 陈炜, 等. Z源逆变器驱动的无位置传感器无刷直流电机反电势过零点检测方法[J]. 中国电机工程学报, 2017, 37(17): 5153-5161. Li Xinmin, Xia Changliang, Chen Wei, et al.Z-source inverter-based approach to the zero- crossing point detection of back EMF for sensorless brushless DC motor[J]. Proceedings of the CSEE, 2017, 37(17): 5153-5161. [2] 周闯, 秦国辉, 王玉鹏, 等. 基于Buck变换器的无刷直流电机无位置传感器控制[J]. 电工技术学报, 2017, 32(12): 197-204. Zhou Chuang, Qin Guohui, Wang Yupeng, et al.Position sensorless control of brushless DC motor based on buck converter[J]. Transactions of China Electrotechnical Society, 2017, 32(12): 197-204. [3] 陈炜, 刘志博, 刘凯, 等. 低速下无刷直流电机三相电压矢量位置检测方法[J]. 电工技术学报, 2017, 32(4): 133-139. Chen Wei, Liu Zhibo, Liu kai, et al. Three-phase voltage vector position detection method for brush- less DC motor under low speed[J]. Transactions of China Electrotechnical Society, 2017, 32(4): 133-139. [4] Iizuka K, Uzuhashi H, Kano M, et al.Microcomputer control for sensorless brushless motor[J]. IEEE Transactions on Industry Applications, 1985, 21(3): 595-601. [5] 刘栋良, 崔言飞, 陈镁斌. 无刷直流电机反电动势估计方法[J]. 电工技术学报, 2013, 28(6): 52-58. Liu Dongliang, Cui Yanfei, Chen Meibin.The estimation method of brushless DC motor back electromotive force[J]. Transactions of China Electrotechnical Society, 2013, 28(6): 52-58. [6] Ogasawara S, Akagi H.An approach to position sensorless drive for brushless DC motors[J]. IEEE Transactions on Industry Applications, 1991, 27(5): 928-933. [7] Shao Jianwen, Nolan D, Hopkins T.A novel direct back EMF detection for sensorless brushless DC (BLDC) motor drives[C]//Applied Power Electronics Conference and Exposition, Dallas, TX, USA, 2002: 33-37. [8] Lai Y S, Shyu F S, Chang Y H.Novel sensorless PWM-controlled BLDCM drives without using position and current sensors, filter and center-tap voltage[C]//IEEE Conference on Industrial Elec- tronics Society, Roanoke, VA, USA, 2003: 2144-2149. [9] Shao Jianwen.An improved microcontroller-based sensorless brushless DC (BLDC) motor drive for automotive applications[J]. IEEE Transactions on Industry Applications, 2006, 42(5): 1216-1221. [10] Lai Y S, Lin Y K.A unified approach to zero- crossing point detection of back-EMF for brushless DC motor drives without current and hall sensors[J]. IEEE Transactions on Power Electronics, 2011, 26(6): 1704-1713. [11] Wei Yanyu, Xu Yongxiang, Zou Jibin, et al.Analytic investigation on commutation angle of brushless DC motors with 120 degrees voltage source inverter[C]// International Symposium on Applied Electro- magnetics and Mechanics, Quebec City, Quebec, CAN, 2014: 219-225. [12] Xu Yongxiang, Wei Yanyu, Wang Baochao, et al.A novel inverter topology for brushless DC motor drive to shorten commutation time[J]. IEEE Transactions on Industrial Electronics, 2016, 63(2): 796-807. [13] 李凤祥, 徐浩, 袁野, 等. 无刷直流电机无位置传感器转子位置辨识策略[J]. 电工技术学报, 2014, 29(12): 107-112. Li Fengxiang, Xu Hao, Yuan Ye, et al.Rotor position identification strategy for brushless DC motor without position sensor[J]. Transactions of China Electrotechnical Society, 2014, 29(12): 107-112. [14] 史婷娜, 肖竹欣, 肖有文, 等. 基于改进型滑模观测器的无刷直流电机无位置传感器控制[J]. 中国电机工程学报, 2015, 35(8): 2043-2051. Shi Tingna, Xiao Zhuxin, Xiao Youwen, et al.Sensorless control of brushless DC motor based on improved sliding mode observer[J]. Proceedings of the CSEE, 2015, 35(8): 2043-2051. [15] Moreira J C.Indirect sensing for rotor flux position of permanent magnet AC motors operating over a wide speed range[J]. IEEE Transactions on Industry Applications, 1996, 32(6): 1394-1401. [16] Xia Changliang, Li Xinmin.Z-source inverter-based approach to the zero-crossing point detection of back EMF for sensorless brushless DC motor[J]. IEEE Transactions on Power Electronics, 2015, 30(3): 1488-1498.
2019, Vol. 34 
