针对压电陶瓷的迟滞特性严重影响了精确定位或跟踪系统的精度,提出了基于Preisach逆模型的前馈补偿滑模自适应控制.为了避免逆模型的精度受原迟滞模型精度的影响,采用逆模型前馈补偿方法.逆模型前馈补偿不依赖于原模型的精度,同时可获得补偿电压,从而减弱迟滞特性;应用了自适应滑模控制方法,减小跟踪误差,并利用Lyapunov稳定性理论证明了所设计的控制器可保证系统全局渐进稳定.最后在Matlab环境中进行仿真.仿真结果表明,系统能够很好地跟踪期望输出,减小跟踪误差,验证了控制方案的有效性.
Hysteresis of piezoelectric ceramics has seriously affected the precise positioning and tracking accuracy of the system.In order to solve this problem,the feed-forward adaptive sliding mode control was proposed based on Preisach inverse model.In order to avoid the problem that the inverse model accuracy by raw lag influence the accuracy of the model,the inverse model feed-forward compensation method was used.The inverse model feed-forward compensation does not depend on the precision of the model,and also can obtain the compensation voltage thus reduced hysteresis.In order to reduce the tracking error,the adaptive sliding mode control method was applied to prove that the designed controller can guarantee the global asymptotic stability of the system by using the Lyapunov stability theory.The simulation results show that the system can track the desired output,and reduced the tracking error.It verifies the effectiveness of the control scheme.