Actuator Saturation Control Based On Dissipative System

In the process of industrial control.as a result of inevitably various errors or unmodeled dynamics,almost all dynamic systems have some uncertainties.These uncertainties may have a great impact on the performance of the system,even sometimes make the system unstable.In most control systems,controllers are drove by actuators,whose physical structure determines that the output of actuators can not be arbitrarily large,in other words,the output has saturation characteristics.As a result of the strong nonlinearity of the saturation characteristic,the traditional controller design is difficult to deal with this nonlinearity.Also,many other facts,such as the aging of components,or the affect of external environment,will also make the controller parameters change slightly.These facts,in some time may degrade the performance of the system,or sometimes affect the stability of the system.As a result of these uncertainties,actuator saturation and controller parameter changing of systems can be seen everywhere in the actual control system,the research of such systems has a strong practical application value.The main purpose of this paper is to design an executive saturation controller for dissipative system.which can keep the system stability under a large time delay and deal with the non-linearity caused by executive saturation.At the same time,the non-fragile method is used to make the controller more accurate.In this paper,we study different systems from the easy to the difficult and complicated,as follow:(1)We study the stability criterion of time delay systems.In electric power systems,chemical systems,network control systems and other industrial process systems,time delay is a common phenomenon.This phenomenon sometimes may degree the performance of the system,and sometimes may even make the system unstable.So we have to consider the influence of time delay when designing controllers.For dissipative systems,time delay is a factor that has to be considered.In this paper,the stability criterion of a class of time-delay systems is studied,and the open-loop stability of the system is studied by means of integral inequality,and then controller with time-delay is designed to improve the closed-loop performance of the system.(2)We consider a kind of fuzzy system.By modeling the fuzzy system with time delay,through a class of new integral inequalities and construct a kind of slack variables(free weights),we have a kind of new stability criterion of the system.Considering the controller also has time delay,and the controller we design should be widely used,this chapter designs a kind of fuzzy controller which can be used in many situations.(3)We discuss the stability of time-delay independent control systems.Because H? control system and passive system are two important branch of dissipative system,the design of controller for H? control system is also a study of dissipative system.Considering the time-delay,we also pay attention to the influence of the new controller on the energy supply function of the system,so in this chapter we design a class of time-delay independent controllers.(4)We study the time-delay Markov Jump dissipative control system.by means of a series of mathematical methods,the stability theorem of a class of dissipative systems is studied.Considering that the saturation phenomenon is a kind of strong non-linearity,we designed a kind of actuator saturation controller.At the end of each chapter,there are corresponding simulation data to test the feasibility of the method in this chapter.