基于PLC的锅炉供热控制系统

沈阳理工大学学士学位论文II摘要随着我国经济的发展，资源和环境矛盾同趋尖锐，使我国的现代化建设面临严峻挑战。作为供热系统重要能源转换设备的燃煤锅炉能耗巨大，占我国原煤产量的三分之一左右。然而，我国目自订运行的很多锅炉控制系统自动化水平不高、安全性低，工作效率和环境污染普遍低于国家标准，因此实现锅炉的计算机自动控制具有重要的意义。本文以某医院锅炉供热控制系统为背景，设计了基于PLC的锅炉供热控制系统。文中给出了通过时间和室外温度相结合的控制策略对系统温度进行调节控制。系统采用模块化设计，每个模块都可以单独的优化，便于整个系统的升级、控制管理和同后的维护，并且具备完全的开发性，保证了系统有良好的可扩充性，保护了用户投资。系统下位机利用西门子PLC(STEP7)进行软件开发，设计了对四台锅炉和五个换热站的计算机控制程序，其中包括对各台锅炉的给煤量、鼓风、引风、出水温度、回水温度、母管压力、汽包水位和蒸汽流量等参数的监测和控制；系统上位机利用西门子工控组态软件WINCC设计，实现系统启／停控制、参数设定、报警连锁保护、历史数据查询、报表打印等功能。文中介绍了一种基于PLC和WINCC的温度自动控制系统方案，针对过程控制装置中的锅炉内胆温度控制系统，通过介绍系统软硬件构成及其特点。详细论述了PLC和WINCC如何实现温度的监控。实践证明，该系统具有良好的人机界面，能方便地在线修改参数，可以实现对整个锅炉系统工艺流程的控制，它在类似的控制系统领域具有很强的生命力。关键字：锅炉；WINCC；温度控制；PLC沈阳理工大学学士学位论文IIIIAbstractWithChina’seconomicdevelopment，resourcesandtheenvironmenthasbecomeincreasinglyacutecontradictions，Sothatthemodernizationofourcountryisfacingaformidablechallenge．Asanimportantenergysourceconversionequipment，heatingsystemoftheindustrialboilerconsumesaboutone-thirdofChina’scoal．However，themajorityofChina’scurrentoperatingboilersystem’ssecurityandefficiencyisgenerallylowerthanthenationalstandard．Soit'sgreatsignificancetoachieveautomaticcontrolforboilerwithcomputer．Onthebasisoftheboilercontrolsystemforsomehospital，thepaperpresentsaoverallcontrolthinking，thesystemdesignedtoheatinginwinterincludessuperordinatecomputercontrolsystemandthesubordinatesystem．Tomeetallthecampus’swinterheating，itgivesacompletecontrolstrategywhichcombinedwithtimeandoutdoor’stemperature．Thedesignofthesystemismodularizedandeachpartcanoptimizealone，it'sconvenientforthewholesystemtoupdateandcontrolmanage．Thesystemiscompletelyopened，Sotheuser’sinvestmentcanbefinelyprotected．ThesubordinatesystemwhichdesignedwithSIMENSPLC(STEP7)controlsandinspectsallthesystem’sparameters，suchasefflentpressure，streamflow，backwatertemperature，etc．ThesuperordinatesystemwhichdesignedwithWINCCinordertodisplaythewindowofstartstop，parameterssetinterface，historicalcurve，ansoon．AndallthesystemsareusedFieldbustoexchangedatas．TheautomatictemperaturecontrolsystembasedonPLCandWINCCisintroduced．Inviewofthetemperatureprocesscontroldevice，throughintroducingthecompositionsandfeaturesofhardwareandsoftwareofthesystem，thedetailshowtomonitorandcontroltemperatureareexpounded．Thepracticeprovesthesystemhasagoodhumanmachineinterfacetoachieveadjustmentsofcontrolparametersonlineandmonitortherunningstateofcontrolledobject．Thissystemcanbewidelyappliedinsimilarfields．Keywords:Boiler；WINCC；Temperaturecontrol；PLC沈阳理工大学学士学位论文IIIIII目录1绪论..............................................................................................................................................11.1工业锅炉国内外发展现状..................................................................................................11.2研究的目的和意义..............................................................................................................11.3课题主要设计的内容..........................................................................................................12锅炉行业概况................................................................................................................................22.1概述......................................................................................................................................22.1.1工业锅炉行业概况....................................................................................................22.1.2工业锅炉的产品现状................................................................................................32.2我国工业锅炉成在的问题及制约发展的因素..................................................................32.2.1目前我国工业锅炉存在的问题................................................................................32.2.2制约工业锅炉发展的因素........................................................................................62.2.3工业锅炉的标准体系................................................................................................72.2.4市场机制的影响及科研开发投入的不足................................................................82.3努力提高工业锅炉行业整体水平......................................................................................82.3.1提高企业的技术开发能力加强技术的开发力度....................................................82.3.2提升工业锅炉的标准水平........................................................................................92.3.3加强市场监管加强市场导向....................................................................................92.4结束语..................................................................................................................................93西门子S7-200系列PLC............................................................................................................113.1概述....................................................................................................................................113.2STEP7--Micro/WIN编程软件.........................................................................................113.3技术参数............................................................................................................................123.4连接S7--200CP