直线超声波电机伺服系统建模及鲁棒控制

Study of Modeling and Robust Control of Linear Ultrasonic Motor Servo System

为解决超声波电机精确建模的问题,将二阶传递函数作为名义模型,通过频域辨识建立超声波伺服系统的线性模型.引入干扰观测器,以抑制各种外部力扰动,并增强伺服系统对参数变化的鲁棒性.以直线超声波电机为例进行仿真和实验,结果表明,控制方法对外部力扰动和参数变化均具有很强的鲁棒性,可以提高超声波电机的运动控制精度.

To solve the problem of precise modeling of ultrasonic motor （USM）, the linear model of its servo system is built using frequency domain identification method and regarding the second-order transfer function as the nominal model. Disturbance observer is introduced in the controller design to decrease all kinds of external force disturbance, and improve the robustness to parameter uncertainties. Computer simulation and experiment were developed for USM, and the results show that the proposed control method has strong robustness to parameter variation and external disturbance, and can improve the motion control accuracy.