Abstract:In recent years, permanent magnet synchronous machine (PMSM) has been widely used in servo drive, rail transit, new energy power generation, and other fields for high power density, high efficiency, good reliability, and fast dynamic response. Three-phase PMSM drive systems usually require at least two phase current sensors to obtain accurate stator current signals. However, in harsh working conditions, the current sensor is prone to various faults or is affected by noise interference, resulting in inaccurate current signals collected. Inaccurate stator current feedback can cause the deterioration of the control performance. Therefore, this paper proposes a three-phase permanent magnet synchronous motor drive method based on a single DC-link current sensor, which reduces the number of current sensors in the drive system. Firstly, the method uses a PI regulator to control the motor speed, and uses the bus current signal and the inverter switching state to reconstruct the stator current as current feedback. The principle of stator current reconstruction is the series effect of DC-link current and three-phase current. Secondly, the method uses the two-step model prediction algorithm to obtain the reference voltage of the next cycle instead of the current cycle. In the current cycle, the control system can simultaneously obtain the reference voltage of the current cycle and the next cycle through the two-step predictive control. Finally, tristate pulse width modulation (TSPWM) selects the appropriate starting and ending voltage vector to modulate the reference voltage of the current cycle according to these two sets of the reference voltage. When the TSPWM selects the appropriate starting and ending voltage vector, the area of the stator current reconstruction dead zone is greatly reduced, and the reconstruction dead zone is all located at the edge of the sector. Therefore, TSPWM can effectively eliminate the influence of the reconstruction dead zone, a tricky problem of traditional space vector pulse width modulation. The simulation results show that the error between the reconstructed current and the measured current is small, which proves that the current reconstruction method has high accuracy in both transient and steady states. When the load of PMSM is set to 4 N m, and the given speed is switched back and forth between 200 r/min and 600 r/min, the drive system can complete the speed adjustment within 10 ms. The actual speed of the motor can quickly follow the given speed, and the overshoot is small. When the load is abruptly changed, the motor speed will not fluctuate greatly. The simulation results show that the motor speed fluctuates only 1.25 % when the load torque is abruptly changed, and it quickly returns to the given speed within 20 ms. In addition, in the steady state of the system, the stator current of the proposed driving method has a high sinusoidal, and the output torque is stable. These simulation results prove the performance of the driving method. Compared with the simulation results, the performance of the control system in the experiment decreases. It is mainly caused by non-ideal factors such as inaccurate motor parameters, inverter voltage losses, and sensor measurement noise. The following conclusions can be drawn from the simulation and experiment. (1) Using TSPWM effectively eliminates the influence of the current reconfiguration dead zone. (2) Compared with other single-bus current sensor driving methods, the proposed method has fixed current sampling points and a lower CMV peak-to-peak value. (3) The method can effectively reconstruct the stator current signal using the DC-link current sensor and has good driving performance in both transient and steady states of PMSM. (4) The method performs better than vector control and traditional single DC-link current sensor driving method.
[1] Zhang Jianzhong, Xu Zheng, Wang Jiayue, et al.Detection and discrimination of incipient stator faults for inverter-fed permanent magnet synchronous machines[J]. IEEE Transactions on Industrial Elec- tronics, 2021, 68(8): 7505-7515. [2] 赵凯辉, 周瑞睿, 冷傲杰, 等. 一种永磁同步电机的有限集无模型容错预测控制算法[J]. 电工技术学报, 2021, 36(1): 27-38. Zhao Kaihui, Zhou Ruirui, Leng Aojie, et al.Finite control set model-free fault-tolerant predictive control for permanent magnet synchronous motor[J]. Transa- ctions of China Electrotechnical Society, 2021, 36(1): 27-38. [3] 陈文汉, 孙丹, 王铭泽. 断相故障下开绕组永磁同步电机模型预测控制容错控制策略研究[J]. 电工技术学报, 2021, 36(1): 77-86. Chen Wenhan, Sun Dan, Wang Mingze.Research on fault-tolerance strategy based on model predictive control for open-winding PMSM system under open- phase fault[J]. Transactions of China Electrotechnical Society, 2021, 36(1): 77-86. [4] 肖飞, 许观达, 连传强, 等. 永磁同步电机单电流传感器系统的三相电流重构策略[J]. 电工技术学报, 2022, 37(7): 1609-1617. Xiao Fei, Xu Daguan, Lian Chuanqiang, et al.Three- phase current reconstruction strategy of permanent magnet synchronous machine drives using a single current sensor[J]. Transactions of China Electro- technical Society, 2022, 37(7): 1609-1617. [5] 王伟, 程明, 张邦富, 等. 电流滞环型永磁同步电机驱动系统的相电流传感器容错控制[J]. 中国电机工程学报, 2012, 32(33): 59-66, 176. Wang Wei, Cheng Ming, Zhang Bangfu, et al.Fault- tolerant control focusing on phase current sensors of permanent magnet synchronous machine drive systems based on hysteresis current control[J]. Proceedings of the CSEE, 2012, 32(33): 59-66, 176. [6] Marčetić D P, Adžić E M.Improved three-phase current reconstruction for induction motor drives with DC-link shunt[J]. IEEE Transactions on Industrial Electronics, 2010, 57(7): 2454-2462. [7] Hafez B, Abdel-Khalik A S, Massoud A M, et al. Single-sensor-based three-phase permanent-magnet synchronous motor drive system with luenberger observers for motor line current reconstruction[J]. IEEE Transactions on Industry Applications, 2014, 50(4): 2602-2613. [8] Kim H, Jahns T M.Phase current reconstruction for AC motor drives using a DC-link single current sensor and measurement voltage vectors[C]//IEEE 36th Power Electronics Specialists Conference, Dresden, Germany, 2006: 1346-1352. [9] Carpaneto M, Fazio P, Marchesoni M, et al.Dynamic performance evaluation of sensorless permanent- magnet synchronous motor drives with reduced current sensors[J]. IEEE Transactions on Industrial Electronics, 2012, 59(12): 4579-4589. [10] 申永鹏, 郑竹风, 杨小亮, 等. 直流母线电流采样电压空间矢量脉冲宽度调制[J]. 电工技术学报, 2021, 36(8): 1617-1627. Shen Yongpeng, Zheng Zhufeng, Yang Xiaoliang, et al.A compatible SVPWM method for DC bus current sampling[J]. Transactions of China Electrotechnical Society, 2021, 36(8): 1617-1627. [11] 申永鹏, 王前程, 王延峰, 等. 误差自校正混合脉宽调制策略[J]. 电工技术学报, 2022, 37(14): 3643-3653. Shen Yongpeng, Wang Qiancheng, Wang Yanfeng, et al.Error self-correction mixed pulse width modu- lation strategy[J]. Transactions of China Electro- technical Society, 2022, 37(14): 3643-3653. [12] 黄政, 陈永军, 刘湃, 等. 基于单电流传感器的永磁同步电机高速控制技术[J]. 微电机, 2022, 55(1): 48-54. Huang Zheng, Chen Yongjun, Liu Pai, et al.Per- manent magnetic synchronous motor high speed control technique based on single current sensor[J]. Micromotors, 2022, 55(1): 48-54. [13] Im J H, Kim R Y.Improved saliency-based position sensorless control of interior permanent-magnet synchronous machines with single DC-link current sensor using current prediction method[J]. IEEE Transactions on Industrial Electronics, 2018, 65(7): 5335-5343. [14] Yang S C.Saliency-based position estimation of permanent-magnet synchronous machines using square- wave voltage injection with a single current sensor[J]. IEEE Transactions on Industry Applications, 2015, 51(2): 1561-1571. [15] Gu Yikun, Ni Fenglei, Yang Dapeng, et al.Switching- state phase shift method for three-phase-current reconstruction with a single DC-link current sensor[J]. IEEE Transactions on Industrial Electronics, 2011, 58(11): 5186-5194. [16] 顾义坤, 倪风雷, 杨大鹏, 等. 基于母线电流传感器的相电流重构方法[J]. 电机与控制学报, 2009, 13(6): 811-816. Gu Yikun, Ni Fenglei, Yang Dapeng, et al.Novel method for phase current reconstruction using a single DC-link current sensor[J]. Electric Machines and Control, 2009, 13(6): 811-816. [17] Li Xiong, Dusmez S, Akin B, et al.A new SVPWM for the phase current reconstruction of three-phase three-level T-type converters[J]. IEEE Transactions on Power Electronics, 2016, 31(3): 2627-2637. [18] Cho Y, LaBella T, Lai J S. A three-phase current reconstruction strategy with online current offset compensation using a single current sensor[J]. IEEE Transactions on Industrial Electronics, 2012, 59(7): 2924-2933. [19] Xu Yongxiang, Yan Hao, Zou Jibin, et al.Zero voltage vector sampling method for PMSM three- phase current reconstruction using single current sensor[J]. IEEE Transactions on Power Electronics, 2017, 32(5): 3797-3807. [20] Lai Y S, Lin Yongkai, Chen C W.New hybrid pulse- width modulation technique to reduce current dis- tortion and extend current reconstruction range for a three-phase inverter using only DC-link sensor[J]. IEEE Transactions on Power Electronics, 2013, 28(3): 1331-1337. [21] Lu Haifeng, Cheng Xiaomeng, Qu Wenlong, et al.A three-phase current reconstruction technique using single DC current sensor based on TSPWM[J]. IEEE Transactions on Power Electronics, 2014, 29(3): 1542-1550. [22] Cacciato M, Consoli A, Scarcella G, et al.Reduction of common mode currents in PWM inverter motor drives[C]//IEEE Industry Applications Conference Thirty-Second IAS Annual Meeting, New Orleans, LA, USA, 2002: 707-714.