基于PLC的锅炉温度控制系统毕业设计

基于PLC的锅炉温度控制系统

作 者 姓 名 xxx 专 业 自动化 指导教师姓名 xxx 专业技术职务 讲 师

目 录

摘 要 ····························································································· 1

第一章 绪论 ·········································································· 3

1.1课题背景及研究目的和意义 ··························································· 3 1.2国内外研究现状··············································································· 3 1.3项目研究内容 ·················································································· 4

第二章 PLC和组态软件基础 ·············································· 5

2.1可编程控制器基础 ··········································································· 5 2.1.1可编程控制器的产生和应用 ······················································· 5 2.1.2可编程控制器的组成和工作原理 ·············· 错误！未定义书签。 2.1.3可编程控制器的分类及特点 ······················································· 7 2.2组态软件的基础··············································································· 8 2.2.1组态的定义 ·················································································· 8 2.2.2组态王软件的特点 ······································································· 8 2.2.3组态王软件仿真的基本方法 ······················································· 8

第三章 PLC控制系统的硬件设计 ······································· 9

3.1 PLC控制系统设计的基本原则和步骤 ········································ 9 3.1.1 PLC控制系统设计的基本原则 ··················································· 9 3.1.2 PLC控制系统设计的一般步骤 ··················································· 9 3.1.3 PLC程序设计的一般步骤 ························································· 10 3.2 PLC的选型和硬件配置 ····························································· 11 3.2.1 PLC型号的选择 ········································································· 11 3.2.2 S7-200CPU的选择 ····································································· 12 3.2.3 EM235模拟量输入/输出模块 ··················································· 12 3.2.4 热电式传感器 ············································································ 12 3.2.5 可控硅加热装置简介 ································································ 12 3.3 系统整体设计方案和电气连接图 ············································ 13 3.4 PLC控制器的设计 ····································································· 14 3.4.1 控制系统数学模型的建立 ························································ 14

3.4.2 PID控制及参数整定 ································································· 14

第四章 PLC控制系统的软件设计 ······································ 16

4.1 PLC程序设计的方法 ································································· 16 4.2 编程软件STEP7--Micro/WIN 概述 ······································ 17 4.2.1 STEP7--Micro/WIN 简单介绍 ·················································· 17 4.2.2 计算机与PLC的通信 ································································ 18 4.3 程序设计 ··················································································· 18 4.3.1程序设计思路············································································· 18 4.3.2 PID指令向导············································································· 19 4.3.3 控制程序及分析 ········································································ 25

第五章 组态画面的设计 ···························································· 29 5.1组态变量的建立及设备连接 ························································· 29 5.1.1新建项目 ···················································································· 29 5.2创建组态画面 ················································································ 33 5.2.1新建主画面 ················································································ 33 5.2.2新建PID参数设定窗口 ····························································· 34 5.2.3新建数据报表 ··········································································· 34 5.2.4新建实时曲线············································································· 35 5.2.5新建历史曲线············································································· 35 5.2.6新建报警窗口············································································· 36

第六章 系统测试 ····································································· 37

6.1启动组态王 ················································································ 37 6.2实时曲线观察 ·············································································· 38 6.3分析历史趋势曲线 ········································································· 38 6.4查看数据报表 ················································································ 40 6.5系统稳定性测试············································································· 42 结束语 ································································································· 43 参考文献 ······························································································· 44 致谢 ······································································································· 45

山东轻工业学院2010届本科生毕业设计（论文）

摘 要

从上世纪80年代至90年代中期，PLC得到了快速的发展，在这时期，PLC在处理模拟量能力、数字运算能力、人机接口能力和网络能力得到大幅度提高，PLC逐渐进入过程控制领域，在某些应用上取代了在过程控制领域处于统治地位的DCS系统。PLC具有通用性强、使用方便、适应面广、可靠性高、抗干扰能力强、编程简单等特点。PLC在工业自动化控制特别是顺序控制中的地位，在可预见的将来，是无法取代的。

本文介绍了以锅炉为被控对象，以锅炉出口水温为主被控参数，以炉膛内水温为副被控参数，以加热炉电阻丝电压为控制参数，以PLC为控制器，构成锅炉温度串级控制系统；采用PID算法，运用PLC梯形图编程语言进行编程，实现锅炉温度的自动控制。

电热锅炉的应用领域相当广泛，在相当多的领域里，电热锅炉的性能优劣决定了产品的质量好坏。目前电热锅炉的控制系统大都采用以微处理器为核心的计算机控制技术，既提高设备的自动化程度又提高设备的控制精度。

本文分别就电热锅炉的控制系统工作原理，温度变送器的选型、PLC配置、组态软件程序设计等几方面进行阐述。通过改造电热锅炉的控制系统具有响应快、稳定性好、可靠性高,控制精度好等特点，对工业控制有现实意义。 关键词：电热锅炉的控制系统 温度控制 串级控制 PLC PID

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