Component-oriented modeling of Networked Control Systems based On CTPN

This paper presents a structure-conserving modeling methods for Network Control System (NCS) by using the Colored Timed Petri Nets (CTPN).The system is considered based on PLC-CPU and the Ethernet architectures. Network transmission time in discrete uniform distribution and packet loss is taken into account. It is integrates the scan cycle of PLC-CPU and the IO-model. The sensor-to-controller time delay data and the controller-to-actuator time delay data are extracted from the model in order to research the relationship between the execution time and system delay. Three kinds of execution time in the model are simulated. By simulation results of the CTPN modeling, the effects to the system by different delay above mentioned are proposed.