基于PLC的城市智能交通灯三路口控制系统设计

AbstractProgrammable Logic Controller for short PLC.Is a comprehensivecommunication,automatic control and computer technology development and themain used for the automatic control system of industrial production.PLC uses thedigital operation system,uses the programmable memory,comes in the storageinternal procedure.Perform logic operations,timing control,sequence control,counting and arithmetic operations,etc.,through digital or analog input outputcontrol of various types of controlled objects and production processes.PLC is amodern industrial use most of the automatic control system.It has programming issimple and easy to learn,strong function,high ratio of performance to price,convenient use strong adaptability,high reliability,strong anti-interference ability,design and installation of debugging work less,convenient maintenance,small size,the advantages of low energy consumption,extensive access to recognized.BecausePLC has the advantages of high reliability,high internal timer resource,and rich ininternal timer resources.It can be used for the "progressive"traffic light system to beaccurately controlled.So PLC is applied in intelligent traffic light control system inChina.Meanwhile,the PLC itself has the function of communication network,aplurality of intersection on the road with a traffic light consists of a LAN unifieddispatching management,can reduce the waiting time of vehicles,reducing the urbanpressure,realize the scientific management of urban traffic.Keywords:Programmable Logic Controller,PLC,intelligent control system,trafficlight,local network.