Stability Analysis And Controller Design For Some Classes Of Networked Control Systems

Networked control systems (NCSs) are feedback control systems in which control loops are closed via digital communication channels. Compared with the conventional point-to-point control systems, networked control systems present a lot of advantages, such as low cost, reduced system wiring, ease of system diagnosis and maintenance, and increased system agility. Currently, the networked control systems are widely used in the field of industrial plants, transportation, power grid, and unmanned aerial vehicles, etc. However, the introduction of communication networks in feedback control loops complicates the analysis and design of networked control systems, because of the network-induced transmission delays, data packet dropouts which inevitably degrade the control performance of networked control systems, or even cause the system to be unstable. Consequently, the research on networked control systems is a hot topic in the control community.In this dissertation, the analysis, and controller design of some classes networked control systems with uncertain network quality, such as network-induced delay, packed dropout are deeply studied. The stable condition for closed-loop systems under the influence of network and controller design method are given by means of Lyapunov stability theory and linear matrix inequality. The main contents are as follows:The problem of state feedback for networked control systems with time delay and data packet dropout is studied. The networked control systems model is established as a kind of system which contains Bernoulli distributed stochastic variables. The existence condition and design approach of state feedback controller which makes closed-loop systems exponentially mean-square stable are given. Furthermore, the H∞control and guaranteed cost control are studied. To show the effectiveness of the proposed schemes, the corresponding simulation is given. Assuming that the sensor is driven by time, the controller and actuator are driven by event, the state feedback controller based on observer for networked control systems with time delay is designed. The conclusion does not demand the system matrix to be invertible. Corresponding simulation is presented to show the effectiveness and superiority of the proposed schemes.Assuming that network only exists between the sensor and the controller, the observer for a class of nonlinear networked control systems under the network and sensor fault environment is designed and the closed-loop networked control systems model is also established by means of Lyapunov stability theory and linear matrix inequality as well as free weight matrix. The stable condition of closed-loop systems and the co-design approach of observer and controller are also given. Simulation is presented to show the effectiveness and feasibility of the proposed schemes.Based on regular, impulse-free and linear time-invariant singular controlled plant, the problem of dynamical output feedback H∞control for a kind of networked control system is studied. The sufficient condition of the existence of dynamical output feedback H∞control law is derived trough Lyapunov theory and linear matrix inequality. The corresponding design method is also given. To show the effectiveness of the proposed schemes, the corresponding simulation is given.The model of networked control systems is established as Markovian jump linear systems with two running modes through state augmentation technique without changing the structure of the initial control systems. Furthermore, the condition for the existence of the mode-depended state feedback control law which makes the networked control systems stochastically stable is derived. The design method for state feedback controller is also given. Corresponding simulation is presented to show the effectiveness of the proposed schemes.Lastly, the summary of the whole dissertation is given and the research directions in the future are put forward.