Research And Application Of Network Control System Modeling And Control Algorithm

With the development and cross—penetration of control of science, computer technology and comunication technology, networked control came into being and is becoming one of the hot topics of the international academic research. The primary advantages of NCS are sharing of information resources, flexibility, good self-diagnosis and maintaining good performance. However, because of inserting the network into traditional control system, it is inevitable for the existence of the information transmission delay which are the main factors to degrade the performance of control systems.In order to reduce or eliminate the impact of network delay to the control system, the theory at home and abroad on the basis of the network control system is referenced,and system modeling, controllers are designed.The main contents are conduded as follows:Firstly,on the basis of the researeh of background, characteristic of NCS,the basic problems are given and the process of development of NCS researeh work is analyzed. Without considering other factors of network, Mathematical modeling of the short delay and long delay of networked control systems is established.Secondly,compared with traditional PID controller, fractional order controller has better adaptability.But the selection of controller parameters is more difficult for a a fractional order controller which introduces additional two parameters λ and μ.For better adaptive capacity of system uncertainty without generality loss,a fractional order controller has been designed which can adjust PID parameters according to system error is presented based on RBF neural network,so that the impact of time-delay on NCS gets mostly compensated.Finally, a NCS simulation platform is established by TrueTime toolbox which provides a simulated network environment to verify the validity of signed controllor. The simulation results evidence that the fractional order PIλDμ controller based on RBF neural network not only makes a good compensation to the impact of time-delay on NCS,but also represent stronger robustness and adaptability. Summarized at the end of this paper, and the prospect.