压电陶瓷驱动器的迟滞特性

Hysteresis characteristics of piezoelectric ceramic actuators

针对压电陶瓷固有的迟滞现象对其定位控制精度的影响,对迟滞进行了特征分析和实验验证。基于微观极化机理和机电耦合效应分析了迟滞的成因,分别对不同驱动行程,全行程不同位置和不同起始电压下的迟滞特性进行了对比实验。结果表明:对10V行程的驱动,随着电压区间的递增,平均位移输出先增大后减小,平均迟滞误差从0.419 3μm减小到0.158 9μm;对100V行程的驱动,随着起始电压的增大,平均位移输出从42.882 5μm减小到25.92μm,平均迟滞误差从3.999 3μm减小到1.692 3μm;起始电压每增加15V,位移输出减小5.654 2μm,迟滞误差减小0.769μm。实验结果反映了电畴翻转状况对驱动过程机电耦合效率的影响,有效验证了电畴翻转理论。实验也表明:针对电畴翻转不同阶段所表现的的迟滞特征对压电陶瓷驱动器的迟滞误差进行补偿,可修正或减小迟滞误差带来的影响,为提高系统定位控制精度提供科学的参考依据。

As the inherent hysteresis phenomena of a piezoelectric ceramic actuator affects its positioning accuracy badly,this paper analyzes and verifies the characteristics of the hysteresis phenomena.The causes of hysteresis were analyzed through microscopic polarization mechanism and electromechanical coupling effects.Some experiments were designed to compare the hysteresis characteristics under different travels,different positions of the whole travel and different initial voltages.The experimental results indicate that：for the driving travel of 10 V,the output of average displacement increases at first then decreases and the average hysteresis error decreases from0.419 3μm to 0.158 9μm as the increases of voltage intervals;for the driving travel of 100 V,the output of average displacement decreases from 42.882 5μm to 25.92μm and the average hysteresis error decreases from 3.999 3μm to 1.692 3μm as the increases of initial voltages.Moreover,when the initial voltage increases by 15 V,the output of displacement decreases by 5.654 2μm on average,and the hysteresis error decreases by 0.769μm on average.These results reflect the influence of domain switching status in the initial phase on electromechanical coupling efficiency in the drivingprocess and also verify the domain switching theory effectively.The experiments suggest that the compensation for hysteresis errors of the piezoelectric ceramic actuator according to the hysteresis characteristics of domain switching in different steps can correct or reduce the effects by hysteresis errors,and can provide scientific reference for improving the control accuracy of positing systems.