毕业设计（论文）-基于PLC的冷轧机厚度控制系统设计精选.doc

编号 毕业设计(论文) 基于PLC的冷轧机厚度控制系统设计 Design of Thickness Control System of Cold-rolling Mill Based on PLC 院（系）名称 电气工程学院 专业名称 测控技术与仪器 学生姓名 学号 指导教师 2010年6月25日 摘要 板带厚度的控制精度是板带生产的重要质量指标，关系到材料的节约，构件的重量以及强度等产品性能。本文设计的冷带轧机板厚控制系统可实现高精度的板带厚度控制，对板带的生产具有重要意义。 冷轧厚度自动控制的基本思想是通过对压下位置、轧制压力、张力的控制来实现对轧件厚度的控制。本系统采用双闭环的控制方式，由厚度闭环构成外环，而内环可以在压力闭环和位置闭环之间进行切换。压力传感器采用MSP300压力传感器，测厚传感器采用x射线测厚仪，位移传感器采用直线位移传感器。选择西门子公司的S7_200CPU224作为PLC控制器用于处理传感器的测量信号，拓展芯片选用EM235模块用于输入各个传感器采集的模拟信号。对于厚度控制系统中由轧机、轧件、轧制工艺等产生的厚度误差，本设计采用轧辊弯曲应力补偿、辊缝补偿、轧制力偏心滤波等方法消除厚差。由于轧辊偏心对板厚的控制影响很大，本文利用偏心补偿的方法实现冷轧钢带厚度的精确控制。 本设计采用PLC实现冷轧机在钢板轧制过程中的厚度控制，具有编程简单，可靠性高等特点。根据厚度闭环参数的自适应调控原理，本设计可实现厚度的精确控制。 关键词：板厚控制；测厚传感器；位置控制系统；轧辊偏心 Abstract The thickness control precision of the cold-rolled sheet is an important quality index for the plate production , which relation to the material saving, the weight and the strength properties of product. The cold rolling mill plate thickness control system designed by this thesis can realize the function of high precision thickness control, it has great significance for the production. Through the control of the position, rolling pressure and tension to control the rolled-piece thickness is the basic idea of Cold-rolled thickness automatic control. This system uses double closed loop control mode, the thickness closed-loop is the outer ring , and the inner ring can be switched between the position and the pressure closed-loop. The article uses MSP300 pressure sensor for pressure detection, X-ray thickness sensor is used for detecting the thickness, and the linear displacement sensor is used for detecting displacement. S7_200CPU224 made by Siemens company is used as the controller for measuring and processing signal, EM235 module is selected for input all analog signals collected from the sensor. For the thickness deviation produced by the rolling mill and the rolling process, this design uses methods such as the roll bending stress compensati