摘要:从上世纪后期开始，PLC技术得到了飞速的发展，在这时期种PLC在处理以下方面得到了较大的提高：数字运算能力、模拟量能力、人机接口能力和网络能力。PLC开始在过程控制的领域中获得一席之地，并在该领域一些应用控制方面取代了原本占据着主导地位的DCS设备。PLC具有适用性强、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在工业自动化控制领域特别是顺序控制中的作用，在未来必将占据主导地位。37612
本文描述烟气废气中存在着大量的热能，如果我们将其直接排放，不但污染浪费资源，而且污染环境。烟气余热回收的原理是讲上位机与PLC相连接，使用组态软件进行系统监控，利用PLC进行控制，通过PID运算器的运算，使得烟气废气与冷水进行热交换处理，从而保持废气与冷水温度差恒定的控制系统,使得烟气废气中的热能得到充分的利用，从而达到节能减排的的效果，降低企业的生产成本的目的。
本文对系统几方面各自进行解释，这些方面有控制设备的运行方法，PLC参数设置，温度变化设备的型号选择，状态程序编制。电热锅炉被改善后，其监测装置可以快速反应，能够长时间工作，性能先进，工作精度大幅提高，可用于工业自动化的实际应用。
毕业论文关键词：回收剩余热量的控制器温度监测PLC; PID
 Flue gas heat recovery system automation design
Abstract:From the late last century,PLC technology has been rapid development in the period in which species PLC handles the following aspects have been greatly improved:digital computing power,analog capability,human-machine interface capabilities and network capabilities.PLC began to gain a foothold in the field of process control,and replaced the original dominates the DCS control system in some applications in the field.PLC has strong applicability,ease of use,wide adaptation,high reliability,strong anti-interference ability,programming and simple.PLC in industrial automation and control areas,especially in order to control the position,in the near future,can not be replaced.This article describes the flue gas exhaust there is a lot of energy,if we direct emissions,pollution not only a waste of resources,but also pollute the environment.Waste heat recovery principle is about the PC connected to the PLC,using the configuration software for system monitoring,the use of PLC controlled by PID arithmetic operation,exhaust fumes and the cold water makes the heat exchange process,thereby maintaining the exhaust gas constant temperature difference between the cold water control system,making the flue gas exhaust heat energy can be fully utilized to achieve the effect of energy saving and reduce the purpose of the production costs.In this paper,to control how the system works,selection of temperature transmitter,PLC configuration,the configuration software design and other aspects of the program will be explained.By the control system of electric boiler has fast response,good stability,high reliability,accuracy and good control characteristics of industrial control has practical significance.

Key words：waste heat recovery control system temperature control PLC; PID
目 录
1. 绪论    1
1.1 课题目的与意义    1
1.2 国内外研究现状与水平    1
1.3 系统工作原理    2
1.4 系统实现的目的及技术要求    2
2. 系统设计    3
2.1 控制原理及数学模型    3
2.1.1 PID控制原理    3
2.2 采集信号及控制量分析    5
2.3 系统组成    6
3.硬件设计    7
3.1 可编程控制器工作原理    7
3.2 系统硬件结构框图    7 PLC烟气余热回收系统自控设计+仿真图:http://www.751com.cn/zidonghua/lunwen_36416.html