改进PLL的永磁同步电机无传感器控制研究

Research on sensorless control of permanent magnet synchronous motors with improved PLL

针对滑模观测算法因高频抖振引起的无感永磁同步电机转子速度和位置估计误差较大、反电动势幅值失配问题,提出一种改进PLL的滑模观测永磁同步电机无传感器控制算法。设计了抑制反向电动势次级谐波的自适应滤波算法,减小了转子速度和位置估计误差;引入幅值归一化算法,解决了因电机参数变化引起的反电动势幅值失配问题,提升了系统的抗干扰能力和动态响应速度。仿真结果表明:新算法的观测精度较高,转速估计误差仅为5 r/min,转子位置估计误差仅为0.1 rad,且在阶跃输入信号下有较强的动态响应性能。

Aiming at the large estimation error in rotor position and speed,and the mismatch of reverse EMF amplitude caused by the high-frequency chattering in the sliding mode observation algorithm,this paper propses a sensorless control algorithm of permanent magnet synchronous motors in sliding mode observation based on improved PLL.The improved new PLL designs an adaptive filtering algorithm to suppress the secondary harmonics of the reverse electromotive force,which effectively reduces the rotor speed and position estimation errors.In addition,an amplitude normalization algorithm is designed to solve the problem of reverse EMF amplitude mismatch caused by changes in motor parameters,and to improve the anti-interference ability and dynamic response speed of the system.The simulation results show that the algorithm based on the improved PLL has higher observation accuracy,the speed estimation error is only 5 r/min,the rotor position estimation error is only 0.1 rad,and it has a higher dynamic response performance under the step input signals.