基于车流的交通灯控制系统设计设计总说明交通发展的状况是衡量一个国家现代化程度的重要标志之一，随着我国交通事业的迅速发展，各种公交、运输汽车和汽车进入家庭的步伐加快使得城市的汽车数量逐年增加，城市道路交通堵塞、拥挤问题显得越来越突出，交通问题已经成为城市解决的必要问题。PLC编程简单,易维护,可以实现不同的功能需求。本文利用西门子S7-300PLC来实现交通灯控制系统的设计，并以上位机世纪星组态软件监控交通灯的运行。本文基于车流检测对交通灯的功能实现如下：在入路口的各个方向附近的地下按要求埋设感应线圈，当汽车经过时就会产生涡流损耗，环状绝缘电线的电感开始减少，即可检测出汽车的通过，并将这一信号转换为标准脉冲信号作为可编程控制器的控制输入，并用PLC计数。首先，本文从CPU选型、PLC的选型、I/O地址的分配以及硬件接线图介绍了整个系统的硬件设计。从交通灯的流程图、梯形图和世纪星的监控画面来完成系统的软件设计。其次，本文介绍了下位机PLC软件设计部分:实现了PLC控制系统对交通灯的控制，分别对正常情况、东西堵车情况、南北堵车情况进行PLC编程。最后，介绍了上位机组态软件的设计，本文采用世纪星组态软件完成了控制系统的监视软件设计。关键词：交通灯，PLC，十字路口，世纪星ATransportationLightControllingSystemDesignBasedonTrafficFlowDesignDescriptionTrafficdevelopmentconditionisoneofimportantsignstomeasureacountry’smodernizationdegree.WiththerapiddevelopmentofChina’stransportationbusiness,allkindsoftransit,transportationvehiclesandvehicleaccesstothefamilymakethecarnumberincreasesyearbyyearandtheproblemsoftrafficjamsmoreandmoreserious.Trafficproblemhasbecometheessentialprobleminthecity.PLCprogrammingissimpleandeasytomaintain,Demandfordifferentfunctionscanberealized.Inthispaper,SiemensS7-300PLCtoachievetrafficlightcontrolsystem,andmorethanslaveCenturyStarConfigurationsonftwaretomonitortheoperationoftrafficlight.Accordingtotherequest,weburyinductioncoilsinthedirectionoftheintersectionofunderground.whenthecarspassbyeddycurrentlosswillresult,insulatedwireringstarttoreducetheinductance,canbedetectedbycar,andthissignalisconvertedtothestandardpulsesignalasaprogrammablelogiccontrollercontrolinput,andcountswithaPLC.Firstofall,thisarticleintroducesthesystem'shardwaredesignfromtheCPU,PLC'sselection,inputandoutputaddressallocationandhardwarewiringdiagram.CompletesystemdesignfromFlowchart,ladder,andmonitorscreenofthecentury.Secondly,thearticledescribesthedesignofPLCwhichislowerpositionsoftware:achievingaPLCcontrolsystemtocontroltrafficlights,respectively,innormalcircumstances,trafficjamsituationinEastandWest,North-SouthtrafficjamsituationinPLCprogramming.Finally,theintroductionofthePCconfigurationsoftwaredesign,thispaperusescenturyconfigurationsoftwaretocompleteofthecontrolsystemmonitoringsoftwaredesign.Keywords:trafficlights，PLC，acrossroads，CenturyStar目录1绪论.............................................................11.1概述.........................................................11.2交通灯研究的背景和意义........................................21.3交通灯的发展形势、现状及国内交通存在的问题...................32可编程控制器PLC..................................................42.1PLC简介......................................................42.1.1PLC的发展................................................42.1.2PLC的定义................................................42.1.3PLC的组成................................................52.1.4PLC的工作原理............................................62.1.5PLC的主要性能指标.................
