Networked Control System Research Of Simulator Methods

The introduction of the network had a fundamental influence upon the control theory as it provided a new way for the development of control theory. However, this system didn't have a well-developed simulation environment. In this paper, two simulation environment: TrueTime and NS-2 are exploited to setup a simulation model of Network Control System (NCS).The performance of them are compared, furthermore, the paper investigates the time-delay problem as well as its compensation methods.1) The dissertation presents an overview of the NCS in research status, method and the primary factors which have influence on the system performance. Extensive measurements of the network's time-delay are conducted. The constitution, the character and the main compensation models of the time-delay problem are analysed.2) In this dissertation we setup a simulation model of the network using the kernel and network models of the Matlab/TrueTime. Then a simulation is conducted in allusion to the network's time-delay and packets-lost problem. The paper analysed the influence of them upon the system's performance.3) The performance and character of the novel network simulation environment NS-2 is studied. The paper takes advantage of the effectiveness of this network and the character of the protocol to setup a simulation model, using "Agent/Plant" protocol. The losing packet and time-delay of this experiment are tested. Furthermore, another system simulation on this NCS is conducted in case of different node number and bandwidth of the net. The influence of the above factors upon the NCS is discussed.4) Using the simulation environment based on NS-2 NCS, a group of time-delay methods compensation are compared. Specially, the dissertation verified the approach of time-delay compensation based on dividing time intervals. On the other hand, we demonstrate the effectiveness of the proposed NCS simulation model.