A feedback control system whose loop is closed through a serial network can be called a networked control system(NCS). NCS is the result of integrating the computer technology, integrated circuit technology, network technology and control theory. With the development of science and technology, it has made much progress while driven by practical demands of social lives. Generally speaking, NCS can be made up with any network, such as Fieldbus,Ethernet and so on. On the other hand, it is the control system only connected with Ethernet/Internet. The introduction of networks benefits much to the control systems while it also causes some problems, such as random network delay, packet dropout and data disorder. Main work and contributions in this dissertation are described as follows: (1)The basic structures and communication protocols of NCS are introduced. The Fieldbus and industrial Ethernet are also mentioned. Moreover, the NetCon system developed by IACAS(Institute of Automation, Chinese Academy of Sciences) is detailed for the use of design and implementation of NCS. (2)The simulaton of NCS is studied. A simplified algorithm of network predictive control system is addressed and its real-time simulations are also realized. There are many different methods to simulate NCS, such as OPNET and NS2 can be used for simulation of networks while the simulation of control systems can be made by Matlab and Scilab. The NetCon and Truetime can combine the simulation of networks with that of control systems. The NetCon system can be employed for real-time simulation. (3)The realization of NCS is addressed and rapid control prototyping is proposed, based on NetCon system a standard development process is given by means of which the experiments based on local/MAN/WAN are realized. A standard research and development process is made up of Modeling, simulation and realization and they can all be completed by NetCon system. Then RCP of NCS is implemented and the process is proved to be effective based on network experiments. (4)The optimal tuning of NCS is proposed. A solution for parameter tuning of network controllers is addressed and by simulation in advance the effects of tuning parameters are verified to guarantee the normal safe running of NCS. Nclib software is firstly programmed in Matlab MEX-file and then it is used for communication between Matlab workspace and the NetCon controller. Optimal parameters are searched by minimizing the cost function until the total process of tuning is finished. (5)The event-driven model of NCS is considered. Simulation and realization of event-driven NCS are executed, based on the NetCon system and a global optimization algorithm of max-min systems is simulated and analyzed. Modeling of finite state machines is given in Stateflow and it is realized with Stateflow Coder using the NetCon system. Finally, the conclusions are given and several prospects of future work are formulated.
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