利用扩张状态观测器的交流永磁同步电机控制

为了提高交流永磁同步电机控制系统的控制品质,保证系统在内外各种扰动的影响下仍能保持快速、无超调、高精度的控制品质,提出了一种改进的控制方式。首先,根据电机模型的特点,分析了影响系统控制品质的因素,包括电流环的动态耦合、速度环的未知扰动等。然后,在介绍扩张状态观测器的原理及功能的基础上,设计了三个扩张状态观测器分别估计速度环和电流环的总扰动,进而设计出具有扰动前馈补偿和误差反馈律相结合的复合控制器。最后仿真和实验均证明了改进的控制策略的有效性。实验结果表明,使用同一组控制器参数,改进的控制策略能够同时实现高低速的高品质动态响应。设定速度为600 r/min时,与传统PI控制器相比,调节时间从0.54 s缩短为0.09 s,速度稳态误差RMS值从2.2 r/min降为1.6 r/min;设定速度为0.01 r/min时,改进的控制策略仍能够保持电机平稳运行,且位置误差在±1码。该控制策略能够满足交流永磁同步电机高精度控制的要求。

PMSM control using extended state observer

In order to improve the control quality of the AC permanent magnet synchronous motor system, guarantee the system can still maintain fast, no overshoot, high precision qualities under the influence of various internal and external disturbances, a modified control method is proposed. According to the characteristics of the motor model, the factors influencing the control quality of the system are first analyzed, which include the dynamic coupling of the current loop, the unknown disturbance of the speed loop, etc. Then, after introducing the principle and function of the extended state observer, three observers are designed respectively to estimate the total disturbance of the current loop and the speed loop, and then a composite control law is proposed, which uses the error feedback control algorithm combining with the disturbance feed forward compensation. Finally, the simulation and the experiment prove the effectiveness of the proposed control strategy. The experiment results show that the modified control law can achieve high quality dynamic response under both high and low speed using the same set of controller parameters. When the setting speed is 600 r/min, compared with the traditional PI controller, the accommodation time is reduced from 0.54 s to 0.09 s, the RMS of the steady speed error is reduced from 2.2 r/min to 1.6 r/min. When the setting speed is 0.01 r/min, the modified control strategy can still maintain the stable operation of the motor and the position error is within ±1 code. The control algorithm can satisfy the high accuracy requirement for the permanent magnet synchronous motor system.