交流伺服系统永磁同步电机电流及位置二级状态观测器设计
Second Level State Observer of Current and Position for Permanent Magnet Synchronous Motor on AC Control System Model

为了提高交流伺服控制系统的反馈精度,并消除反馈信号的滞后问题,针对永磁同步电机电压控制模型及其运动学控制模型进行深入分析,并在此基础上对控制系统反馈环节的工作时序进行分析,得到了电流及位置反馈环节的滞后周期数,提出电流及位置一级状态观测器。通过当前控制周期反馈位置及电流值,对下一个控制周期的电流及反馈位置值进行精确估计,并将一级状态观测器的观测输出值作为二级状态观测器的输入,进一步抑制电流及位置反馈信号的高频振荡及时滞。结果表明:二级电流及位置状态观测器对反馈信号的高频噪声起到明显的抑制作用,并对反馈值进行了准确的预计观测;二级位置观测误差小于0.005 rad,并消除了反馈中夹杂的高频噪声。将该方法应用于交流伺服控制系统中,进行高速高响应定位控制,响应频率达到200 Hz,加速度达到62 831 rad/s2,此时系统相电流稳定,定位精度达到1.5°,从而实现了电流及位置的精确观测。
The voltage control model and the rotor kinematic model of PMSM(permanent magnet synchronous motor) are analyzed to improve the feedback accuracy of servo control system and to solve the delay problem of feedback signal. The analyzing results are further used to analyze the work timing of control system’s feedback loop and the number of hysteretic cycles is obtained. Then, a first level state observer of current and position for PMSM is proposed. The current and position values in the current control cycle are used to obtain accurate estimations of the current and position values in the next control cycle, and the observation output of the first level state observer is served as the input of the second level state observer so that the high frequency oscillation and the time？？delay of the current and position’s feedback signal can be further suppressed. Results show that the second level state observer of current and position has a significant inhibition on the high frequency noise and an accurate prediction on the feedback value. The observation error of the second level position is less than 0.005 rad, and the high frequency noise included in feedback has is eliminated. When the proposed method is applied in an AC servo control system for position control with high speed and high response, the response frequency of the system reaches 200 Hz, and acceleration arrives at 62 831 rad/s2, and its positioning accuracy is 1.5, while the system’s phase current is stable. It can be concluded that the proposed method realizes the accurate observation on current and position values