Design Of The Control System Based On PLC And Touch Screen For The Post-processor Of Copper Foil

Copper is necessary material in electronic industry. With the development of electronic information industry, higher requirements are put forward for the quality and yield of copper. The post-processor is used to deal with the surface of copper, and the control system plays a decisive role. However, there were complex wiring, single man-machine interaction, fussy operation, poor reliability and great difficulty for maintenance in the traditional control system of the post-processor machine, which is the important issue for quality and quantity of the product. So, in this paper, variable frequency regulating speed technology, tension control technology, and PID control technology are researched. Through analyzing the basic principle and control request of the post-processor, a new control system is designed with the method of combining touch screen with PLC.This paper analyzes the force acting in the process of the post-processor, establishes the strong-coupling nonlinear relationship between speed and tension, and brings forth in a decoupling control algorithm based on the study of tension control technology. What's more, variable frequency system and tension control system are modeled and emulated, and the PLC program and human-computer interface are designed. Through the touch-screen replacing the buttons, indicator lights and instrumentations of traditional control system, the operation is simplified; the cost is saved; the automation has been strengthened.The detailed content of this paper shows as follows:(1) Through analyzing the present situation of copper industry, the problems existing in domestic post-processor are found out. So the technology of combination PLC with touch screen is proposed to improve the post-processor control system.(2) Basing on the principles and technical target of the post-processor, this paper analyzes the force acting during the process, finds out the factors impacting tension, and developed a decoupling control strategy of tension and speed. Moreover, the PID control algorithm and its parameter modulating method are studied in this paper. Finally, hardware design of the post processor control system is completed.(3) Variable frequency system and tension control system are modeled and emulated, and method for PID parameter modulating is advanced. (4) Through anglicizing the control requests, control algorithms are provided, and the PLC control program design is completed by the method of modular programming, which includes the software implementation of speed control and tension control. According to the specific request and production process, man-machine interface for the control system is designed referring to PLC control program.(5) Install and execute the post-processor control system, and analyze the results by a large number of experiments, after that, the system parameters and control algorithms are modified further.Field experiments show that the new control system is safe and reliable, good for human-computer interacting, so that the quality and yield of the copper foil have been largely improved.