学位论文-—基于plc的天然气调压站的智能监控系统设计.doc

基于 PLC 的天然气调压站的监控系统设计

摘 要

管道燃气供应以其方便、经济，安全等优点得到广泛应用，正逐步取代瓶装

供气。燃气具有易燃、易爆的特点，为了保证燃气供应的安全并实现最佳调度，

必须及时掌握系统运行状态，了解压力、流量、温度等数据。本天然气调压站智

能监控正是基于以上需求的基础上研制而成的。、本文首先对调压站智能控制系统

进行分析，确定系统的功能目标和性能要求，并提出调压站智能控制系统总体方

案设计框架，本天然气站智能监控系统以 CPU224XP 控制核心，以传感器(压差传

感器、温度传感器，压力传感器等)用来做检测元件，以电磁阀为执行机构．CPU

ABSTRACT

The supply of conduit gas spreads widely because of its advantages such as：

convenience，economy,and safety etc,It gradually replaces the bottle packing gas．Gas

is flammable and explosive．In order to ensure the safety of gas supply and realize the

best adjustment，we must master the status of the system and datas such as pressure，

controlling the action of related electromagnetism valve. firstly,the thesis analyse the

significance of the intelligent supervision of the gas station．Confirms system function

goals and performance parameters,and then putsforward the designing overall frame and

dividing into function modules．

KeyWords：Gas station for pressure adjustment；PLC；Communication；Mon itoring

System；ModbusProtocol

目录

第 1 章 绪 论 ...................................................................................................................1

1.1 可编程控制器的产生与定义 ............................................................................1

1．3．1 可编程控制器的特 ............................................................................4

1．3．2 可编程控制器在工业控制系统中的应用 ........................................5

1．4 课题背景 ..........................................................................................................7

1．4．1 天然气城市输配系统的构成 ............................................................7

1．4．2 天然气城市输配系统压力级制的确定 ............................................7

1．4．3 门站 ....................................................................................................8

1．4．4 国内外研究现状 ................................................................................8

第 2 章 天然气调压站监控系统总体设计 .....................................................................9

2．1 监控系统设计方案考虑 ..................................................................................9

2．1．1 控制方式的选择 ................................................................................9

3．1 电气控制柜的设计 ........................................................................................13

3．2 模拟量采集电路 ............................................................................................15

3．3 信号转换与隔离 ............................................................................................15

3．4 PLC 控制电路 ................................................................................................16

3．5 显示器电路 ....................................................................................................17

3．6 通信网络的设计 ............................................................................................18

3．6．1 网络拓扑 ..........................................................................................18

3．6．2 传输介质 ..........................................................................................18

3．6．3 通信接口 ..........................................................................................18

第 4 章 天然气调压站监控系统软件设计 ...................................................................20

5．3 软件可靠性设计 ....................................................................................................29

致谢 .................................................................................................................................31