Stability Analysis Of Networked Control Systems

With the development of the network technology and computer technology, the control system based on network has substituted traditional point-to-point control system. The closed-loop control system through network is called networked control systems (NCS). The NCS can realize resources sharing and improve the system reliability and flexibility; it can be installed and maintained easily.Uses the Lyapunov stability theory, and use the method of the improved free-weight matrix, the stability analysis and controller design for NCSs with network-induced delay and data packet dropout studied in this dissertation when the network-induced delay and data packet dropout as two basic questions study objects.For the linear continuous NCSs which does not consider the data packet loss in the transmission process, has established the NCSs with single input and output system model. For the NCSs with single-packet transmission, this thesis has considered the network induced time-delay and data packet dropout in the transmission courses, and has gained the stability criterion of the system by the method of the improved free-weight matrix, at the same time, under the situation of given controller and based on the LMIs, this thesis has also obtained the calculation method of the maximum allowable network induced time-delay.For a class of nonlinear and uncertain NCSs with network-induced delay and data packet dropout, a new closed-loop modeling:The Takagi-Sugeno (T-S) fuzzy model is adopted for representing NCSs. And the fuzzy model is used to approximate the nonlinear NCSs so that local linearization. Considered account parameter uncertainty norm-bounded properties, and time-delay systems based on the theory and method of Lyapunov function and LMIs, the controller design method is given. The results expressed as a form of LMIs.