plc控制系统在煤气加压机中的应用_毕业论文

PLC控制系统在煤气加压机中的应用摘要：煤气加压机用于煤气输送，是钢铁、煤炭、石化行业的重要设备，其电气控制方式多采用仪器仪表和继电-接触器系统断续控制，自动化程度和可靠性低，难以保证控制精度，且无法实现网络通讯和远程监控。本文设计了一套基于PLC的煤气加压机控制系统，实现了煤气加压自动控制；对装备现状与发展趋势进行了研究，提出了总体设计方案，选用FR-F740变频器实现风机调速，选用SBWR/Z温度传感器、EJA压力传感器实现现场数据采集，并将信号送至三菱FX2N-32M型PLC；设计了闭环控制PID算法，按照逻辑控制与过程控制结合的程序设计思路，基于GXDeveloper编程软件，开发了变频器控制程序，实现了风机的转速控制，设计了系统过载保护、故障报警、停机自动连锁等功能子程序。结果表明，采用PLC控制的煤气加压机具有操作简单、运行精良、抗干扰能力强、编程简单、控制精度高的特点，提高了系统的可靠性，通过PLC组网，实现远程监控，较好的达到了设计目的。关键词：煤气加压机；PLC；闭环控制；PID；变频器AppliacationofPLCcontrolsystemingaspressuremachineAbstract：Gaspressuremachineisusedintransportofgas,itisanimportantdeviceintheindustryofiron,steel,coalandpetrochemical.Itselectricalsystemmostlyuseinstrumentsandrelay-contactortocontrol.itisdifficulttoguaranteethatcontrolprecision,andunabletoperformnetworkcommunicationsandremotemonitoring.ThisarticlehasdesignedaPLC-basedgascontrolsystem,achievedtheautomaticcontrolofgaspressure.Situationanddevelopmenttrendoftheequipmenthasbeenstudied,proposeddesignplan,useFR-F740frequencytocontrolfanspeed,UseSBWR/Ztemperaturesensors,pressuresensorsEJAtofielddatacollection,andsendthesignaltoMitsubishiFX2N-32MPLC;designedaclosed-loopcontrolPIDalgorithm,followlogiccontrolandprocesscontrolprogramdesignidea,developerprogrammingsoftwarebasedGX,developedtheinvertercontrolprogramforfanspeedcontrol,anddesignasystemoverloadprotection,alarmdowntimefeaturessuchasautomaticchainsubroutine.TheresultsshowedthatusePLCcontrolofgashasasimpleoperation,runsophisticated,uding,programmingsimple,controlandhighprecision,increasedsystemreliability,throughnetworking,PLCforremotemonitoring,betterdesigngoalisreached.Keywords:gaspressuremotor;PLC;loopcontrol;PID;VFD目录1绪论.............................................................................................................................11.1课题背景...........................................................................................................11.2煤气加压机装备现状与发展趋势...................................................................21.3控制系统的国内外发展现状..........................................................................31.4煤气加压机系统控制的概念..........................................................................42PLC控制系统概述....................................................................................................62.1PLC简介..........................................................................................................62.2PLC的发展......................................................................................................62.3PLC控制系统的结构与工作原理..................................................................73武钢煤气加压机控制系统总体方案设计.................................................................93.1控制系统组成..................................................................................................93.2原系统存在的问题........................................................................................103.3系统控制要求及目的....................................................................................103.4系统改造方案.................................................................................................104系统硬件设计与选型...............................................................................................124.1鼓风机选型.....................................................................................................124.1.1鼓风机结构特点....................................................................................124.1.2鼓风机结构和主要参数........................................................................134.2变频器选型.....................................................................................................144.3变送器选型.....................................................................................................154.3.1压力变送器............................................................................................154.3.2温度变送器............................................................................................164.4低压电器元件选型.........................................................................................175系统软件设计...........................................................................................................195.1设计思想及设计依据.....................................................................................195.2煤气出口压力定值控制系统设计.................................................................195.3I/O分析..........................................................................................................215.4PLC主机与I/O模块选型.............................................................................215.4.1PLC主机选型.......................................................................................215.4.2I/O模块选型.........................................................................................225.5外部接线图.....................................................................................................225.6程序流程图....................................................................................................235.6.1气压调节流程图.......................................