多压电驱动器系统迟滞和蠕变前馈补偿控制

压电驱动器具有迟滞和蠕变等非线性特性,影响定位精度和限制系统性能。提出一种同时补偿多个压电驱动器迟滞和蠕变的控制方法。通过基于模型的开环控制补偿实现单个压电驱动器的线性化,将含有多个补偿后线性化压电驱动器的系统视为线性系统,应用叠加原理构建影响系数矩阵描述压电驱动器间的耦合效应。在前馈通路串联影响系数逆矩阵与多个线性化压电驱动器实现系统开环补偿控制。实验结果表明在阶梯形信号作用下,多压电驱动器系统的迟滞和蠕变特性同时显著减小,表明开发的前馈补偿控制方法在准静态应用中是有效可行的。

Simultaneous compensation of hysteresis and creep by feed-forward control for the system with multiple piezoelectric actuators

Hysteresis and creep effects in piezoelectric actuators severely affect positioning accuracy and limit system performance. This paper aims at developing a control methodology to compensate hysteresis and creep for the system with multiple piezoelectric actuators. The hysteresis and creep in single piezoelectric actuator is firstly compensated by using model-based open-loop control. Then the system with multiple linearized piezoelectric actuators is considered as a linear system. The superposition principle is used to construct the influence coefficients matrix representing the couple effects between the piezoelectric actuators. The inverse influence coefficients matrix is solved and is cascaded with multiple linearized piezoelectric actuators to decouple the system, and the feed-forward compensation is realized. Experimental results show that in the case of step-like reference signals the hysteresis and the creep for the system with multiple piezoelectric actuators can be significantly reduced at the same time. It implies that the developed methodology is effective and feasible in practice.