基于割率的线性方程抗迟滞方法

Anti-hysteresis method of linear equation based on cutting rate

针对压电陶瓷驱动器固有的迟滞特性对定位及控制精度的影响,找到了一种基于割率的线性方程抗迟滞方法。首先计算出迟滞曲线上升、下降轨迹各采样点及目标修正直线的割率比,即割率系数β;将采样电压与对应β的关系曲线分段拟合成线性方程组;最后将采样电压带入方程组求出修正电压,作出驱动控制曲线。结合上述抗迟滞原理,驱动器的最大迟滞误差从14.543%减小为1.268%,重复性误差小于1.497%,非线性误差小于4.497%。相对于繁琐复杂的建模算法,该方法能以比例放大及加法运算电路的形式实现对迟滞曲线的修正,算法仅为一次方程组,具有更高的可实施性和可操作性,为进一步提高压电陶瓷驱动器的定位及控制精度提供了科学的参考依据。

Aiming at the influence of the inherent hysteresis characteristics of the piezoelectric ceramic actuator on the positioning and control accuracy,a linear equation anti-hysteresis method based on cutting rate is found.Firstly,the sampling points of the rising and falling trajectories of the hysteresis curve and the cutting rate ratio of the target correction line are calculated,the ratio is the cutting rate coefficientβ.The relationship curve between the sampling voltage and correspondingβis fitted segmentally into a linear equation group.Finally,the sampling voltage is inputted into the equation group to obtain the correction voltage,and the driving control curve is made.Experiment results:with the above anti-hysteresis principle,the maximum hysteresis error of the driver is reduced from 14.543%to 1.268%,the repeatability error is less than 1.497%,and the nonlinear error is less than 4.497%.Experiment conclusion:compared with the cumbersome and complex modeling algorithm,the proposed method can realize the correction of the hysteresis curve with the form of proportional amplification and addition operation circuit.The algorithm is only one-order equation group,which has higher implementation feasibility and operability.The algorithm provides a scientific reference for further improving the positioning and control accuracy of piezoelectric ceramic actuators.