毕业设计--基于三菱FX2N-48MR型号PLC交通信号灯控制

摘要如今，交通信号灯安装在各个十字路口，已经成为指导交通车辆最常见和最有效的手段。随着社会的进步，人们的消费能力不断的提高，很多人购买私家，导致现在的交通拥堵不堪。因此采用有效的方法控制交通灯是势在必行的。PLC能够把东西方向或南北方向的车辆按数量多少进行统计，然后计算出给定东西方向与南北方向的红绿灯时长。这样就可以实现按车流量大小给定绿灯时长，达到最大限度的有车放行，减少十字路口的车辆滞流，缓解交通拥挤、实现最优控制，从而提高了交通指挥系统的效率。PLC的应用正在不断地走向深入，也带动了传统控制行业更新发展。PLC具有结构简单、编程方便、可靠性高等优点，已广泛用于工业过程和位置的自动控制中。它对使用环境适应性强，同时其内部定时器资源十分丰富，可对目前普遍使用的“渐进式”信号灯进行精确控制，特别对多岔路口的交通控制可方便地实现。因此现在越来越多地将PLC应用于交通信号灯系统中。同时，PLC本身内部还具有通讯联网功能，能够将同一条道路上的信号灯组成一局域网进行统一调度和管理，可以缩短车辆等候时间，实现科学化人性化的管理。在实时检测和自动控制的PLC应用系统中，PLC往往是作为一个核心部件来使用。关键词：交通灯，PLC，车流量，最优控制常州工学院电子信息与电气工程学院毕业设计说明书IIAbstractToday,thetrafficlightsinstalledatvariouscrossroads,hasbecomethemostcommonandmosteffectivemeansofguidingtransportvehicles.Alongwithsocialprogress,people'sspendingpoweriscontinuouslyimproving,manypeoplebuyprivate,resultingingridlockedtraffic.Thereforeaneffectivemethodtocontrolthetrafficlightsisimperative.PLCtotheeast-westornorth-southdirectionofthevehicleaccordingtothenumberthenumberofstatistics,andthencalculatethelonggiventhetrafficlightsoftheeast-westdirectionandnorth-southdirection.Thiscanbeachievedgiventhegreenlighttrafficflowsizeandduration,toachievemaximumvehicleclearance,reducingthecrossroadsofthevehiclestagnation,relievetrafficcongestion,toachieveoptimalcontrol,therebyincreasingtheefficiencyofthetrafficcontrolsystem.PLCapplicationiscontinuouslydeepening,hasalsoledtothedevelopmentoftraditionalcontrolindustryupdates.PLChasasimplestructure,easyprogramming,highreliability,hasbeenwidelyusedforautomaticcontrolofindustrialprocessesandlocation.Itsuseenvironmentadaptability,whileitsinternaltimerresourcesareveryrich,precisecontrolofthecurrentwidespreaduseofprogressivesignal,inparticulartrafficcontrolinthemulti-forkcanbeeasilyimplemented.SonowmoreandmorethePLCusedintrafficlightssystem.Atthesametime,thePLCitselfinternalcommunicationsnetworkingcapabilities,unifiedschedulingandmanagementofthelightsonthesameroadtheabilitytoformalocalareanetwork,vehiclewaitingtimecanbeshortenedtoachievescientificandhumanemanagement.Inreal-timedetectionandautomaticcontrolofthePLCsystem,PLCisoftenasacorecomponenttouse.Keywords:trafficlights;PLC;trafficflow;optimalcontrol目录摘要.....................................................................................................................................................................IAbstrac..............................................................................................................................................................II第1章绪论......................................................................................................................................................11.1研究背景、意义..................................................................................................................................11.2智能交通的国内外发展状况.............................................................................................................11.3交通信号灯控制理论的研究现状.....................................................................................................21.4本文的主要工作内容.........................................................................................................................2第2章PLC可编程控制器...............................................................................................................................32.1可编程控制器的由来与发展.............................................................................................................32.1.1可编程控制器的由来.............................................................................................................32.1.2可编程控制器的发展.............................................................................................................32.2PLC的定义.........................................................................................................................................42.3PLC的工作原理.................................................................................................................................42.3.1分时处理和循环扫描方式.....................................................................................................42.3.2PLC的两种工作状态.............................................................................................................42.3.3输入输出滞后时间.................................................................................................................42.4可编程控制器(PLC)的特点...............................................................................................................52.5PLC的编程语言.................................................................................................................................52.6PLC的结构.........................................................................................................................................62.6.1中央处理器（CPU）...............................................................................................................72.6.2存储器.....................................................................................................................................72.6.3输