燃油锅炉PLC控制的程序设计毕业设计（论文）word格式.doc

编号 本科生毕业设计 学 生 姓 名 专 业 学 号 指 导 教 师 分 院 电子工程 2012年6月   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CO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。 用PLC控制燃油锅炉的启动、停止、出现异常情况时能暂停且异常消失后能自动按起燃顺序重新工作。燃油经燃油预热器预热，由喷油泵经喷油口打入锅炉进行燃烧。燃烧时，鼓风机送风；喷油口喷油；点火变压器接通(子火燃烧)；瓦斯阀打开(母火燃烧)，将燃油点燃。点火完毕，关闭子火与母火，继续送风、喷油，使燃烧持续。锅炉的进水和排水分别由进水阀和排水阀来执行。上、下水位分别由上限、下限水位开关来检测。蒸压力由蒸压力开关来检测。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 contro