Research Based On Piezoelectric Ceramics Hysteresis Nonlinear Modeling And Control

With the development of science and technological development, fields of human study continue to explore in depth, the range of operation of the object has from the macroscopic deeps to the microscopic fields. In order to achieve ultra-precision machining, precision measurement operations, it needs to achieve nanometer-level accuracy and dynamic performance of the system requirements are getting higher and higher.Piezoelectric ceramic has advantages such as: small displacement high resolution, high frequency response, no noise, no heat etc., therefore it becomes an ideal micro-displacement actuator component. Using voltage-driven piezoelectric ceramic has the characteristics of hysteresis and this characterizer made it difficult to control. To solve this problem, this paper uses a combination of theory and practice research methods, based on the polarization behavior of piezoelectric ceramic, the mathematical model of hysteresis of piezoelectric ceramic has been established and then do research on hystereis control of piezoelectric ceramic.This paper discuss the hysteresis of piezoelectric ceramic, from the point of view of micro-domain, it analysis driven mechanism of the piezoelectric ceramic. From the microscopic point of view to explain hysteresis by electric domains theory and the phenomenological theory .and then the piezoelectric ceramic electric hysteresis mathematical model is established, the hysteresis mathematical model can accurately describe the hysteresis phenomenon, and it also laid the foundation for research of control method.The paper describes the parameter identification methods of hysteresis model in detail, and then inverse control system of piezoelectric ceramic is designed. In order to improve control accuracy, based on the inverse control, the feed-forward PID control is applied; experimental results show that using this control method the piezoelectric ceramic actuator could arrive satisfied tracking precision. The control precision has greatly improved; the hysteresis effect has decreased to 0.5%.Based on the static hysteresis model of piezoelectric ceramics, according to its dynamic hysteresis characteristics, the paper discusses the dynamic hysteresis model of piezoelectric ceramic. The piezoelectric ceramics dynamic hysteresis model includes the linear part and non-linear part .at first the linear part of the model is identified by frequency-domain characteristics of piezoelectric ceramics. Based on the linear part model, it will be further defined the non-linear part, that is define its relative parameters'scope. We can get piezoelectric ceramic dynamic hysteresis model by this way. At first it will compensate the piezoelectric ceramic dynamic hysteresis, secondly we adopt the LMI-Smith controller, which not only embodies the advantages of Smith predictor, but also it can reduce the impact in of the closed-loop control system which caused by estimation error, moreover, it is easy to realize by physical implementation. Using this method to control piezoelectric ceramics nonlinear dynamic hysteresis the control effect is good.Through theoretical study and experimental validation, this paper mainly describe the research work of the piezoelectric ceramic micro-drive system, it helps to improve the performance, and also beneficial to the further application of piezoelectric ceramics at areas such as the ultra-precision machining, nano-positioning technology and micro-electromechanical systems. The research results have important theoretical meaning and practical application value.