Construction Of Master-slave Control System Of Multi-point Process And Real-time Analysis

PLC technology,Fieldbus technology and Industrial Ethernet technology are hot fields of automation technology currently. According to professional ethics construction of Control Theory and Control Engineering of Maoming University, taking PCT-I process control equipment as research target, using PROFIBUS technology and SIMATIC NET Industrial Ethernet technology to build a master-salve control system which based on three layers network framework. The construction of control system could provide a good hardware and software environment for students and teachers.Firstly, the research background of this issue, research significance and relating to the relevant technologies are briefly introduced. Then the introduction of two key technologies-PROFIBUS fieldbus and SIMATIC NET Industrial Ethernet are given in-depth analysis and research. In order to build master-slave control system and carry on the real-time performance analysis, PROFIBUS-DP protocol communication model, protocol struction and characteristics are introduced emphatically.On this basis, a master-slave control system is built by PLC of SIEMENS S7-300/200 series in this article. And network configuration, hardware selection, programming and system monitoring interface design of this control system are discussed in detail. Management and monitoring layer of the control system uses SIMATIC NET Industrial Ethernet technology, realizing online remote monitoring. The using of PROFIBUS-DP fieldbus technology in field apparatus layer has realized CPU315-2DP master station to three intelligent slave station CPU224 for real-time monitoring.As the continuous improvement of control requirements, the control system also needs higher network real-time performance requirement. So, the research of fieldbus communication model and real-time performance turned to be more important. At the end of this article, a typical DP/PA hybrid network control system is built and relatively real-time reach and analysis is given in detail.