The Study Of CONFORM Production Line Computer Supervisory Control System

The Programmable Logic Controller ( PLC ), owing to its high reliability, high stability , and easiness in programming and using, has been extensively used in the process control system of production line in the modern industry enterprises. But the PLC cann't provide the user with the dynamic display of production line's state messages or the output of the report forms, however utilizing the industrial computer( EPC ) , the users can develop convenience graphical interfaces, with the support of numerous software. Nowadays, it has already become one of the directions that combining PLC with IPC to the development of industry automation.The TLJ300 copper Continuous Extrusion Forming (CONFORM) production line made in our college has achieved the lead position in domestic similar equipment. But when it compared with the similar product made in abroad, the technology gap still exists in automatic control system, which mainly include the large control panel, the great plenty of switchs and the complexity of wire connection. Otherwise, the controlling of the extrusion cavity's temperature and the extrusion wheel's rotate velocity is completely depended on the workers' experience, which result in the big errors and low precision. In order to further increase the efficiency and to enhance the grade of the automatic control system , the CONFORM production line's computer supervisory control system is developed.In this paper, an integrate method of supervising and controlling the CONFORM production line which uses PLC and IPC is introduced. This system is the improvement of it's original control system, which uses IPC as the upper computer and uses the configuration software as the users' customization operation flat in which the line's real-time control and the state display is performed. As the reliability and stability of the PLC, it is used to acquire data, execute the upper computer's commands, perform the logic control and the real-time control of the extrusion cavity's temperature etc.After reform, the control functions are executed only by the PLC itself and independent of the upper computer. As far as the control method is concerned, the fuzzy control is chosened to simulate the manual work, because the temperature has the non-linear, inertia and hysteresis characters, which lead to the difficulty of establishing an accurate math model.The results of system simulation and debugging show that the computer supervision system runs steadily and reliably, also, the performance of the temperature fuzzy control system is excellent, which has a better robust capability. The whole computer supervisory control system has met the anticipative requirements.