Research On Robust State Estimation Of Time-delay Linear Discrete Systems

Modern industry has put forward higher and higher requirements for system estimation and control.In the process of modeling the actual system,model errors are inevitable and the forms are complex and diverse,which leads to the problems of large limitations or complex research methods in the research results of robust state estimation theory for time-delay systems.At the same time,the multi-sensor robust fusion technology of time-delay systems also has many problems that need to be resolved.Therefore,it is very necessary to explore a robust state estimator with small time delay and extend it to the work of multi-sensor information fusion.This paper proposes a robust state estimation algorithm for time-delay systems that allows model errors to affect system parameters in any form,and applies it to the robust information fusion of time-delay systems.The specific research questions are as follows:First,the problem of robust state estimation for uncertain linear discrete systems with d-order state lag is discussed.Based on the principle of minimizing the expected error of estimation and the method of state augmentation,a robust state estimation algorithm for time-delay systems that allows model errors to affect system parameters in any form is proposed.The estimation error covariance of this algorithm is bounded.The conditions and its asymptotic properties are proved.Finally,the effectiveness of the estimator is verified by a numerical simulation example.Second,based on the above conclusions,the robust fusion estimation problem of multi-sensor systems with state lag and uncertain model errors is studied.Firstly,a time-delay robust state estimator based on the expected minimum estimation error and state augmentation is used to obtain the local state estimation value,and then the weighted fusion method is used to fuse the local information in the monitoring center.Finally,the effect of the robust fusion estimator is verified through a numerical simulation example.Third,based on the results of robust fusion estimation researched in the previous chapter,the problem of robust estimation fusion for multi-sensor systems with communication constraints is discussed.First,a data-driven transmission strategy is introduced,and then the analytical expression of the fusion estimator based on this strategy is derived.Then some conditions are proposed to ensure the boundedness of the estimation error covariance matrix of the fusion estimator,and relevant proofs are given.Finally,the fusion estimator is compared with other fusion estimators through some numerical simulation examples,which proves its good fusion estimation performance.