Anti-disturbance Control For Stochastic Systems Based On Disturbance Observer

The problems of anti-disturbance control for stochastic systems with disturbances have been an hot topic and have attracted widely research of scholars at present.Under the above background,a series of disturbance-observer-based control(DOBC)are proposed for some classes of stochastic systems with different disturbances in this paper.The main contents are stated as follows:(1)A class of stochastic systems with multiple disturbances are considered.The disturbance which is described by an exogenous system can be rejected by DOBC,and the disturbance which is supposed to be a norm-bounded vector can be attenuated by H_? control.Based on which,composite disturbance-observer-based control(DOBC)and H_? control(DOBPH_?C)scheme is proposed.It is proved that all of the signals in the composite system are mean-square stable,its H_? performance satisfies a prescribed level.Finally,simulation examples are given to verify the feasible of the proposed scheme compared with DOBC methods.(2)Anti-disturbance control problem is studied for a class of discrete-time stochastic systems with multiple disturbances.The multiple disturbances are same as above.DOBPH_?C scheme is designed to deal with the system.It is proved that all of the signals in the composite system are mean-square stable,its H_? performance satisfies a prescribed level.Finally,simulation example shows the correctness and effectiveness of the proposed strategy.(3)A class of stochastic systems with multiple disturbances are studied.A stochastic adaptive disturbance observer is designed to estimate the disturbance which can be generated by a linear exogenous system with unknown parameter,and it can represent unknown frequency.Based on which,a control scheme is proposed for the system.It is guarantee that all of the signals in the composite system are asymptotically bounded in mean square.Finally,simulation example is given to demonstrate the correctness and effectiveness of the proposed method.