Event-triggered control and filtering for networked systems based on network dynamics
thesisposted on 06.12.2017, 00:00 by Y Lin
With the development of computing and communication technology, networked systems in which information is exchanged through communication networks have become prevalent in a variety of practical applications. A considerable number of these systems have scarcely adequate computation and communication network resources. Notice that, network dynamics usually affect the quality of the performance of networked systems; network-based control or filtering design generally interferes with the quality of service of communication networks. Therefore, successful implementation of networked systems over communication networks requires the adequate integration of control or filtering with intelligent computation and communication networks. This research establishes an information scheduling middleware to effi- ciently utilise the limited communication resources and the computation capacity while preserving the desired performance of networked systems. In this proposed middleware, an event-triggered scheme is given to provide a tradeoff between the performance of networked systems and the utilisation of communication network resources. A scheduling mechanism is derived to avoid traffic congestion in the communication network by introducing a fluid-flow model. By using this information scheduling middleware, the issues of network-based control and filtering are investigated. First, a fluid-flow model of the communication network and an eventtriggered scheme are integrated to develop a new framework, in which the criteria of stability and stabilisation are derived for networked systems under simultaneous consideration of control system performance and network dynamics. Second, based on network dynamics, an online scheduling strategy is proposed to design the H∞ filter for networked systems in the framework with the information scheduling middleware, the Information Dispatching Middleware (IDM). Third, the IDM is applied to distributed control for large-scale networked systems and a codesign method is obtained to determine the parameters of the IDM. Fourth, the mechanism of the IDM is analysed to investigate the cooperation between the Information Selection Module and the Congestion Avoidance Module in the IDM. Based on the IDM, distributed filters are designed considering the dynamics of communication networks. Finally, numerical and practical examples are given to demonstrate the effectiveness and advantages of the proposed information scheduling middleware.