压电定位系统的自抗扰控制设计
Active disturbance rejection control design for piezoelectric positioning system

纳米定位系统中广泛采用的压电驱动器因存在非线性、多映射的迟滞特性而严重影响了纳米定位系统的 定位精度. 为消除迟滞对定位精度的影响, 将其视为干扰, 设计不基于迟滞及定位系统精确数学模型的自抗扰控制 算法, 利用扩张状态观测器实时估计迟滞, 进而补偿其对定位精度的影响, 获得了良好的定位系统控制仿真效果. 仿 真结果表明, 自抗扰控制器能够有效消除迟滞、提高纳米定位系统的定位精度
Piezoelectric actuator are commonly used in nanopositioning system. However, nonlinear and multivalue properties, i.e. hysteresis, of piezoelectric materials, which are commonly taken in piezoelectric actuators, will decrease the accuracy of nanopositioning systems. In order to remove the influence of hysteresis, nonlinear and multivalue properties are viewed as the disturbance of system. Active disturbance rejection control (ADRC), a control approach which does not depend on accurate model of hysteresis and nanopositioning system, is designed to achieve the desired control object. Extended state observer is employed to estimate hysteresis, and then it can be compensated in real time. Nice control performance is acquired in the numerical simulations. From the simulation results, we may see that ADRC is able to cancel hysteresis and improve the accuracy of nanopositioning system effectively.