发布时间：2015-01-18 来源：人大经济论坛

自动化专业论文范文 目录 摘 要I AbstractII 1 绪 论1 1.1课题研究的背景和意义1 1.2锅炉的基础知识2 1.2.1锅炉的定义2 1.2.2锅炉的发展2 1.2.3锅炉的工作4 1.2.4锅炉的结构5 1.3 PLC的基础知识6 1.3.1 PLC的定义6 1.3.2 PLC简介7 1.3.3 PLC的特点（与继电器比较）7 2 系统程序的设计9 2.1燃油锅炉的运行及示意图9 2.2 控制要求10 2.3 燃油锅炉的运行框图10 2.4 PLC机型的选择11 2.4.1 方法1. 按以下条件选择机型11 2.4.2 方法2.按以下要求选择机型13 2.4.3 方法314 2.4.4 PLC容量估算17 2.5 系统的I/O接口以及硬件接线图20 2.6 系统控制的梯形图22 2.6.1起动22 2.6.2停止23 2.6.3异常状况自动关火24 2.6.4锅炉水位控制25 2.6.5系统总梯形图26 2.7 系统的示警电路29 3 用移位寄存器来设计系统的程序30 3.1 移位寄存器的定义功能30 3.2 移位寄存器的操作过程30 3.3 移位寄存器的作用30 3.4 用移位寄存器绘制系统的控制图31 3.4.1启动31 3.4.2停止32 3.4.3异常情况时34 3.4.4水位控制35 3.4.5 系统控制过程总梯形图35 4 总 结39 致谢41 参考文献42 附录 指令表43 摘 要 自从20世纪60年代末第一台PLC问世以来，已很快被应用到机械制造、冶金、矿业、轻工业等各个领域。PLC是采用微电脑技术制造的通用的自动控制设备，它具有高可靠性，能适应工业现场的高温，冲击震动等恶劣环境，广泛应用于机械设备、生产流水线和生产过程的自动控制。PLC主要具有逻辑运行功能，可以代替继电器进行开关控制、具有定时控制的功能、记数控制功能、步进控制功能，A/D、D/A转换功能，数据处理功能，通信，联网功能，并配置了较强的监控功能 燃油锅炉和建筑物自备发电机随着城市发展而越来越多地应用。以前使用燃煤锅炉由于其在燃烧时产生大量的CO2和粉尘污染环境而逐渐被淘汰，相对应的用燃油锅炉来代替燃煤锅炉已被广泛用于宾馆、大型商场等建筑。由PLC组成的燃油锅炉控制系统适用于配用各种进口及国产燃烧器的燃油锅炉，对锅炉实行全自动控制，包括锅炉水位、蒸汽压力、燃烧系统的参数检测、指示、报警、调节等进行控制。 关键词：可编程序控制器 燃油锅炉 控制系统 Abstract Since the 20th century, PLC has quickly been applied to machinery, metallurgy, mining, light industry, and other fields after the first PLC been invented in the late of 1960s. PLC is an overall automatic control equipment which been manufactured by micro-computer technology. PLC has some advantages. It has high reliability. It suit to the high- temperature industrial environment and the adverse environmental like the impact shock .It also can widely used on mechanical equipment, production lines and the production process automatic. PLC has the logic operation function to replace relays for switching control, with timing control functions, numeric control functions, step control functions A/D, D/A conversion functions, data processing functions, communications, networking functions and control functions of stronger watch. Fuel boilers and city- owned generators of buildings been applied extensively with the development increasingly. The coal combustion boilers used previously have been gradually eliminated .Because it has large number of CO2 and dust pollution of the environment .The corresponding fuel oil boilers has replaced coal-fired boilers and have been widely used in hotels, shopping centers and other buildings. PLC control system applicable to fuel boilers with combustion devices in a variety of imported and domestically fuel boilers to implement fully automatic boiler control, including boiler water control, steam pressure controller, combustion system parameters detection control, instructions control and warning control. Key words: programmable controller fuel boiler control system