压电陶瓷驱动器ECNLP动力学模型及其位移跟踪控制器的研究

Study on ECNLP Dynamics Model of Piezoceramic Actuator and Position Tracking Controller

针对压电陶瓷驱动器中存在的复杂非线性滞回动力学特性,首先建立了一种新型机电耦合非线性集总参数(Elec- tromechanical coupling nonlinear lumped-parameter,ECNLP)模型.该模型不仅能够准确、合理地刻画压电叠堆中的非线性滞回动、静态特性,而且充分考虑了驱动器中弹性和运动部件的动力学特性.基于此模型,利用微分几何的输入输出线性化原理,实现了该模型的精确线性化变换,并导出了相应的线性可控规范型子系统.根据该子系统,提出了一种基于LQ方法的压电陶瓷驱动器非线性位移跟踪控制系统,并进一步验证了余下内动态子系统的稳定性.最后,通过仿真计算检验了系统的控制效果。

On account of the complex nonlinear hysteresis behaviour of piezoceramic actuator, in this paper, a novel electromechanical coupling nonlinear lumped-parameter （ECNLP） model of piezoelectric dynamic system is proposed. In this model, not only the static and dynamic characteristics of piezoceramic stack＇s nonlinear hysperesis, but also the dynamics of elastic and motive components within actuator are considered simultaneously. Based on the proposed model, the input-output linearization theory is utilized to implement the exact linearization, and deduced a subsystem presented with a linear controllable normal form. Utilizing this subsystem, a nonlinear position tracking control system is developed for piezoceramic actuator by adopting LQ method, and the stability of remaining internal dynamics is validated similarly. At last, the control performance is confirmed through computer simulations.