Fault-Tolerant Control For Networked Control System With Actuator Fault

With the development of technology about computer, communication and control, networked control system which is an entirely distributed real-time networked feedback control system arises. It has many merits, such as sharing information source, reduced wire, easy expansibility and maintenance, which make it win wide application fields. But the induced delay, packet dropout and packet disordered are the concomitants of the network, all of which combined with the complexity of the system make it sensitive to faults. Actuators play a key role in the control system. If any of them is faulty, the effect to the system is incalculable. This paper studies the fault-tolerant control (FTC) of networked control system with actuator fault, which also considers about the effect of induced delay, packet dropout, packet disordered and quantization error.Firstly, we study the fault-tolerant control of networked control system with actuator disabled fault. Constant induced delay is considered. To model the process of packet dropout, iterative method is adopted. Aiming at handling with the actuator disabled fault, the controller gained is obtained by robust integrality theory.Secondly, fault tolerant control for NCS is studies, in which physical plant with time varying state delay is considered. Piecewise constant states feedback controller is adopted to cope with the induced delay, packet dropout and disordered. For the problem of the actuator disabled fault, the delay-dependent stability sufficient condition for the system is obtained at a continuous view by choosing appropriate Lyapunov function.Further more, aiming at the actuator disabled fault, the problem of guaranteed cost active fault-tolerant for networked control systems is studied. Ideas about controller designed off-line and chosen on-line are adopted. To cope with induced delay,packet dropout and disordered, piecewise constant states feedback controller is still utilized. The optimal guaranteed cost controller is obtained by a standard optimal problem. Further more, the controller choice on-line strategy is proposed. Comparison with other methods in the simulation example demonstrates the advantages of this method.Finally, the paper concerns the quantized H∞fault-tolerant control for networked control system (NCS) with partial actuator fault. It focus on the effect to the stability of the control system by the quantized data. The quantization error produced by the time invariant logarithmic quantizer at the sensor and controller is modeled. Then we establish a general model, which combines induced delay, packet dropout, disordered, quantization error and the actuator partial fault together. By H∞control method, the piecewise constant states feedback controller is obtained, which can ensure both the asymptotic stability and the interference suppression H∞performance.