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Robust Control Of Nonlinear Systems With Hysteresis

Posted on:2005-01-07Degree:DoctorType:Dissertation
Country:ChinaCandidate:D K ZhangFull Text:PDF
GTID:1118360185974192Subject:Control theory and control engineering
Abstract/Summary:PDF Full Text Request
The problem of control on nonlinear systems with hysteresis has been put forward since 1960's. Nonlinear systems with hysteresis could been controlled by choosing appropriate apparatuses and approximately replacing systems with hysteresis by linearization systems in lower demand on control. In the situation of demand on low precision, using resistance and capacitance bridge circuit or charge control could mitigate hysteresis. It is difficult from material to come over the effect caused by hysteresis on performance of controlled systems, with higher and higher demand on control precision in high precision process and all kinds of national defense systems recently. So it is task with important theory significance and application value, to study form control consideration the control of nonlinear systems with hysteresis to come over the effect by hysteresis on systematic performance, and gets highly attention in control and mechanic engineering field home and abroad. It can adapt to high demand on systematic performance in all kinds of precision control. However, hysteresis also exits in other field, for instance, economy and physiology.Systems with hysteresis are nondifferentiable nonlinear systems. So they cannot be studied through control theories and methods used in differentiable nonlinear and linear systems. A general model for hysteresis form control consideration is put forward in this dissertation after studying characteristic of hysteresis, which consists of two parts: linear part and uncertain nonlinear part with known limit. Systems with hysteresis can be looked as nonlinear systems with uncertain input, and studied through robust control theory used in nonlinear systems.Sliding mode control (SMC) is especially suitable to apply in the robust control on nonlinear systems with uncertainty due to simpleness of algorithm, quickness of response and good performance of anti-disturbance. However, chattering which can result in breakage of hardware and even instability in systems greatly limits the application of SMC. At the same time, there exits crossover in getting control law and manifold in algorithm of SMC, and the control design becomes complex, especially in high order systems. Ackermann's Formula is employed to improve algorithm of SMC in this dissertation, and the crossover disappears. Mode-reference SMC is employed then to...
Keywords/Search Tags:Nonlinear systems with hysteresis, Terminal SMC, Model-reference SMC, Ackermann's Formula, Exact linearization, Hybrid Systems
PDF Full Text Request
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