Delay Of The Network Control System Research

Networked control systems is the closed loop feedback system via computer network which consists of plant, sensor, controller and actuator connected by the network. It has many attractive advantages which include low cost, simple installation and maintenance, increased system agility and reduced system wiring, resource shared, remote control and operation, high system testability etc. However, there exist a lot of problems in networked control systems, such as networked-induced delay, data dropout, etc. They have a great influence on the system stability; at worst they even collapse the system.This paper firstly focus on the uncertain networked control system with long time-delay. The disturbation is added on the right of the state equation. The sufficient condition for the uncertain networked control system with long time-delay which is subject to the closed-loop system asymptotic stability and H_∞performance is mainly derived based on the Lyapunov function and Linear Matrix Inequality(LMI). The H_∞state feedback controller is designed at last. The simulation example for the uncertain networked control system with long time-delay shows the effectiveness and feasibility of the proposed method.The new variable-period sampling scheme for networked control systems with random time delay based on BP neural network prediction is secondly given so as to alleviate the influence of the time delay on networked control systems. How to model, analyze and control networked control systems adopting BP neural network are specially presented in this passage. The time delay that can be predicted online using BP neural network tool is chosen as the sampling period. The key point is that the new generalized model that can be applied in the practical condition is strongly recommended.