Font Size: a A A

Research On The Stability And H_? Performance Of The Variable Period Sampling System

Posted on:2019-01-29Degree:MasterType:Thesis
Country:ChinaCandidate:Z Y FengFull Text:PDF
GTID:2438330548972635Subject:Operational Research and Cybernetics
Abstract/Summary:PDF Full Text Request
In the digital society,the sampled-data system is widely used in the social practice.It is used in the fields of the network control system,the multi-agent system and digital filtering.So the sampled-data system research has received widespread attention.The basic characteristic of the sampled-data system is the stability.So the stability has always been the focus of research workers.In real life,the sampled-data system is more or less affected by external interference.The interference can aggravate the performance of the system,and may lead to the system instability.So the study of the H_?performance for the sampled-data system is great significance.The paper will use the Lyapunov-like functional and input delay methods to study the stability and the H_?performance of the sampled-data system,and obtain the stability criterion and the condition of the H_?performance of the sampled-data system.The organizational structure of this paper are as follows:Chapter 1 describes the research background of the sampled-data system,the present study situation of stability and H_?performance for the sampled-data system,and at last introduces the main content of this paper.Chapter 2 is about the theoretical knowledge needed for the research of the sampled-data sys-tem.It includes the Lyapunov stability theory and linear matrix inequality(LMI)theory.Moreover,some related lemmas are given,which are used in the process of the proof.Chapter 3 is concerned with the sampling-interval-dependent stability of the sampled-data system under aperiodic sampling by the Lyapunov-like functional method.A new Lyapunov-like functional is constructed,which contains the cross term of the state and its derivative.Then by tak-ing advantage of a new inequality to deal with the Lyapunov-like functional derivative,based on the Lyapunov-like functional method,we obtain a new result about the sampling-interval-dependent stability.The result is extended to the sampled-data system under aperiodic sampling with poly-topic uncertainty,we obtain a new criteria about the robust asymptotical stability.Finally,using the LMI toolbox in MATLAB,three examples show that the proposed result has less conservatism than some existing ones.Chapter 4 studies the H_?performance of the sampled-data system under aperiodic sampling by the input delay method.Firstly,the new Lyapunov function is constructed by introducing the integral of quadratic form of the state.Next the Jensen inequality and Wirtinger-based integral inequality was applied,and according to the bounded reality lemma,the condition of the H_?performance were given.Lastly,the LMI toolbox in MATLAB is used,and three examples show that the obtained results are less conservative.Chapter 5 briefly summarizes the research content of this paper,and also points out the prospect of the future study work.
Keywords/Search Tags:Sampled-data system, Lyapunov-like functional, Sampling-interval-dependent stabil-ity, Polytopic uncertainty, H_?performance
PDF Full Text Request
Related items