Analysis And Research On Several Problems Of Networked Control Systems

As computer network technology, embedded system development,coupled with large scale integrate circuit bring low hardware price,make web-based environment of complex control systems into a new application trends. With the development of the remote control and an objective requirement of complex control system, the network control system analysis and synthesis of control theory quickly become one of the focus. The insertion of network in control systems inevitably bings the problems such as network-induced delay,data packet dropouts.The performance of these problems. Therefore, it is positive and significant to carry out research work in the field of networked control systems.Firstly, the modeling and control of NCS are investigated.The model of rudder motor load simulation system is established and a class of NCS with stochastic delays is studied.Then PID control,fuzzy-PID control and fuzzy self-adaptive PID control are used and simulation results are given.Secondly,studied the H∞-based network delay and packet loss of networked control system respectively. Modeling and stability of networked control are investigated,also the controller design.Base on lyapunov stability theory and linear matrix inequality method, corresponding state feedback H∞controller design method is given. Make the closed-loop networked control system achieve robust stability,then verificated by simulation.Then the real-time simulator TrueTime based on Matlab/Simulink is introduced. Truetime simulation model is established,also simulation analysis and the effect comparison of different parameters on system stability are presented aiming at using PID control,fuzzy-PID control and fuzzy self-adaptive PID control when control plant is rudder motor load simulation system. By the simulation graphs of the system, the relation between performance and time-delay,data packet dropout rate,network load disturbance,sampling period is discussed.In Truetime simulation environment,verifated by simulation in ChapterⅢ,ChapterⅣ,the simulation results show that the controller designed is effective.