内蒙古科技大学
本科生毕业设计说明书（毕业论文）
题 目： 皮带配料自动称重控制系统 学生姓名： sipoyi 学 号： 19890215 专 业： 自动化 班 级： 3级2班 指导教师： ***
内蒙古科技大学毕业设计说明书（毕业论文）
皮带配料自动称重控制系统
摘 要
皮带配料自动称重系统是精细化工厂生产工艺过程中一道非常重要的工序，配料工序质量对整个产品的质量举足轻重。本设计以烧结机配料系统为工业背景，针对配料的自动控制问题，提出了一种基于PLC的皮带配料称重自动配料系统的控制方案。利用PLC实现对模拟信号的采集、流量的计算、PID调节和对变频器、电机等设备的控制任务。
皮带配料自动称重系统的恒流量控制采用PID调节，流量计量控制是计量偏差与变频调速的结合。依据系统工艺流程本设计介绍了配料系统的流量控制方式和系统控制过程，详细讲述了PLC的选型及PLC配料系统变频控制中的硬件设置、参数设定和软件设计过程。
关键词：S7-200PLC；变频调速； PID控制；恒流量控制
I
内蒙古科技大学毕业设计说明书（毕业论文）
The belt ingredients automatic weighing control system
Abstract
Belt ingredients automatic weighing system is a very important process in fine chemical production process, the quality of ingredients process is an important quality of the product as a whole. This design, the sintering machine batching systems for industrial weighing Automatic batching system based on PLC belt ingredients control program for the automatic control of the ingredients. The use of PLC's acquisition of analog signals, traffic calculation, PID regulation and control tasks on the drive, motor and other equipment.
The belt ingredients automatic weighing system, the constant flow control using PID control, flow measurement control is a combination of measurement bias and frequency control. Batching system flow control method and system control process in accordance with the system process design, detailed account of the hardware settings in the selection of the PLC and PLC batching system inverter control, parameter setting and software design process. Key words: S7-200PLC; Frequency Control; PID control; Constant flow control
II
内蒙古科技大学毕业设计说明书（毕业论文）
目 录
摘 要 ......................................................................................................................................... I 第一章 绪论 .............................................................................................................................. 1
1.1概述 .............................................................................................................................. 1 1.2设计背景 ...................................................................................................................... 1 1.3工艺流程 ...................................................................................................................... 3 第二章 皮带配料自动称重系统 .............................................................................................. 6
2.1设计总体介绍 .............................................................................................................. 6 2.2上位机介绍 .................................................................................................................. 8
2.2.1 概述 .................................................................................................................. 8 2.2.2 工作原理 .......................................................................................................... 8 2.3恒流量控制介绍 ......................................................................................................... 9
2.3.1 概述 ................................................................................................................ 9 2.3.2 PID调节原理 ................................................................................................. 9 2.4 西门子S7—200简介 ...............................................................................................11
2.4.1 概述 ...............................................................................................................11 2.4.2 一般特性 ...................................................................................................... 12 2.4.3 扩展模块 ...................................................................................................... 13 2.5 变频器简介 .............................................................................................................. 15
2.5.1 概述 .............................................................................................................. 15 2.5.2 变频器的基本结构 ...................................................................................... 15 2.5.3 变频器的分类 .............................................................................................. 16
III
内蒙古科技大学毕业设计说明书（毕业论文）
2.5.4 变频器中常用的控制方式 .......................................................................... 16 2.6 皮带电机简介 .......................................................................................................... 16
2.6.1 概述 .............................................................................................................. 16 2.6.2直流调速与交流调速的优劣比较 ............................................................... 17 2.6.3 异步电动机的变频调速原理 ...................................................................... 18 2.7 电子皮带秤简介 ...................................................................................................... 21
2.7.1 概述 .............................................................................................................. 21 2.7.2基本组成部分 ............................................................................................... 22 2.7.3原理 ............................................................................................................... 23 2.7.4特点 ............................................................................................................... 23 2.8光电编码器简介 ....................................................................................................... 24
2.8.1 概述 .............................................................................................................. 24 2.8.2工作原理 ....................................................................................................... 24 2.8.3编码器分类及特点 ....................................................................................... 25
第三章 控制方案的确定及其实现方法 ............................................................................ 28
3.1设计的总体任务及实现的功能 ............................................................................... 28
3.1.1自动称重配料系统控制要求 ......................................................................... 28 3.1.2设计任务 ......................................................................................................... 28 3.2控制思想的确定 ....................................................................................................... 29 3.3具体系统设计方案 ................................................................................................... 30
3.3.1 测速环节 ...................................................................................................... 30 3.3.2称重系统 ....................................................................................................... 31 3.3.3电机的PID调速 ........................................................................................... 31
IV