The Study Of DMC Application In Networked Control Systems

This paper analyses development and present researchful state of NCS, generalizes the exsiting problems and research achievements and method. This paper introduces NCS basic problems, then uses the classic PID control strategy designing controller of NCS to compensate time delay.In domestic and international papers, NCS controller design has many strategies, but there are many inadequate. The paper adopts the Dynamic Matrix Control(DMC) theory designing controller to compensate for time delay, then applying this method into long time delay MIMO NCS and applying forecast feedforward compensation DMC into long time delay SISO NCS. DMC is good at linear systems, but its capacity of anti-disturbance is not very good. In this paper, according to the changes of object state, DMC parameters are calculated in real-time. By this method, disturbance in NCS can be dealed and it achieves good results. Finally improving forecast feedforward compensation DMC algorithm, the paper decoupling the state of the object from input and output directions. In accordance to the decoupling subsystem it gives a performance function and brings up bidirectional decoupling DMC. It greatly improve algorithm for accuracy.In order to prove effectiveness of NCS algorithm design, experiment must be carried out. Therefore design and implementation of NCS hardmare simulation platform is necessary. In this paper, the design of NCS hardmare simulation platform uses star network structure with a switchboard connecting three computers, first as an object, second as a controller, third as network congestion Data Sources. This paper uses C++ to write program of controller and object math model. Communication between controller and object uses WinSock API. Third computer uses Multicast software to make network time delay. Finally, experiment in the NCS hardmare simulation platform verify the effectiveness of the theory method proposed in this paper.