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Robust Adaptive Control Of Nonlinear Systems With Hysteresis

Posted on:2007-11-04Degree:DoctorType:Dissertation
Country:ChinaCandidate:Y FengFull Text:PDF
GTID:1118360185474193Subject:Control theory and control engineering
Abstract/Summary:PDF Full Text Request
In the recent years, with the increased requirement of the control precision and speed for the precision processing and production facility, it has attracted significant attention by the control industry that the advanced smart material-based sensors such as piezoceramics and the driving technique and the corresponding hysteresis phenomena. The exhibition of hysteresis phenomena usually causes undesirable inaccuracies or oscillations and even instability. It has very important theoretical significance and applied value that modelling to describe the hysteresis characteristics and the control approach for the nonlinear systems with unknown hysteresis.The classical control approach is that establishing the inverse hysteresis model in order to mitigate the effects of hysteresis, but owing to the more dependence to the model parameters for the establishment of inverse hysteresis model, the stability of closed-loop system can not be analyzed in some cases. In the thesis, the existing hysteresis models are introduced systematically, and a hysteresis model which is convenient for the controller design is set up. For the nonlinear systems with unknown hysteresis, the hysteresis model is combined with the advanced control approach not the inverse hysteresis model, and the systematic design procedures are used to enable the global stability of a large class of nonlinear systems with unknown hysteresis.In the thesis, several differential hysteresis models are analyzed such as Backlash-like model, Preisach model, Prandtl-Ishlinskii model and KP model. Based on the structure expression of Backlash-like model, Prandtl-Ishlinskii model is divided into linear part and nonlinear part. According to the characteristics of stop and play operators, and it is convenient for the controller design.Preisach model is one of the hysteresis models which are widely utilized in the hysteresis modeling. As the preliminary analysis for the dynamic hysteresis characteristics, a dynamic hysteresis description whose output is influenced by the input variation rate is presented by acting the input variation rate on the Preisach function based on the classical Preisach model. From the simulation results, the applied field is presented.To mitigate the influence of unknown hysteresis, according to the matching condition of reference model, the model reference adaptive control approach is presented for a class of continue linear system with unknown Prandtl-Ishlinskii...
Keywords/Search Tags:Hysteresis Model, Backstepping Design, Model Reference Adaptive Control, Robust Adaptive Control, Nonlinear System
PDF Full Text Request
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