Output Feedback Control Problem For Two Classes Of Stochastic Nonlinear Systems

The control problem of stochastic nonlinear systems is one of the important problems in the control theory and applications.It is also a hot issue in the control research fields.At present,the researches on the state feedback control of stochastic nonlinear systems have made great achievements.But in the most of situations,the system states are not measurable for a practical system.Therefore,there are more practical significance in the study of output feedback control of stochastic nonlinear system.This thesis mainly studied the output feedback stabilization problems of two kinds of stochastic nonlinear systems,and the feasibility and advantages of the proposed method are verified by the simulation examples.The main contents are as follows:1.The first part deals with the output-feedback stabilization problem for a class of stochastic upper-triangular nonlinear systems.By using the homogeneous domination approach and constructing an implementable homogeneous reduced-order observer,an output-feedback controller is designed to ensure that the equilibrium at the origin of the closed-loop system is globally asymptotically stable in probability and the output can be regulated to the origin.2.Based on the stochastic nonlinear time-delay system stability criterion and homogeneous domination approach,the second part solves the global decentralized output-feedback stabilization problem for a class of large-scale stochastic high-order nonlinear systems with multi-delays.By skillfully choosing an appropriate LyapunovKrasoviskii functional and successfully overcoming some troublesome obstacles in the design and analysis procedure,the decentralized output-feedback controller and homogeneous observer are constructed for each subsystem to guarantee that the closed-loop system is globally asymptotically stable in probability.