基于直线音圈电机运动平台的线性自抗扰控制研究

Study on Linear Active Disturbance Rejection Control Based on Linear Voice Coil Motor Motion Platform

运动平台是机床设备中重要的组成部分,广泛使用的机械导轨式运动平台定位精度难于突破微米级,摩擦是影响机械导轨式运动平台定位精度的主要原因。为解决摩擦作用导致的运动平台动态性能难以提升的问题,针对直线音圈电机运动平台设计了一种线性自抗扰控制器。将PD控制器和带模型信息的扩张状态观测器相结合,带模型信息的扩张状态观测器可以根据控制输入量和位置误差估计出平台运动过程中受到的摩擦力,并在控制输入量中进行补偿。该观测器很好地补偿了摩擦扰动,从而提高了系统的鲁棒性和跟踪性能。仿真实验表明:该线性自抗扰控制器与PID控制器相比,可有效提高直线音圈电机运动平台的动态性能。

The motion platform is an important part of the machine tool equipment. The positioning accuracy of the widely used mechanical guide rails type motion platform is difficult to break through the micrometer level, friction is the main reason that affects its positioning accuracy. In order to solve the problem that the dynamic performance of the motion platform was difficult to be improved due to the influence of friction, a linear active disturbance rejection controller was designed for the linear voice coil motor motion platform. PD controller was combined with the extended state observer with model information.The extended state observer with model information can estimate the friction force received during the platform motion according to the control input and position error, and compensate in the control input. The friction disturbance was compensated well by using the observer, thus the robustness and tracking performance of the system were improved. Simulation experimental results show that the linear active disturbance rejection controller can be used to improve the dynamic performance of the linear voice coil motor motion platform effectively compared with the PID controller.