毕业设计（论文）十字路口交通信号灯控制.docx

摘 要自从交通灯诞生以来，其内部的电路控制系统就不断的被改进。设计方法也开始多种多样，从而使交通灯显得更加智能化。作为交通控制的重要组成部份的交通信号灯也应适合社会实际情况。这是选择制作十字路口交通灯的目的。可编程控制器(PLC)以微处理器为核心，普遍采用依据继电接触器控制系统电气原理图编制的梯形图语言进行程序设计，编程容易，功能扩展方便，修改灵活,而且结构简单，抗干扰能力强。西门子可编程控制器指令丰富，可以接各种输出、输入扩充设备，有丰富的特殊扩展设备，其中的模拟输入设备和通信设备更是符合交通灯控制系统的要求与特点，能够方便地联网通信。本文选择西门子可编程控制器S7-200为核心部件，着重进行硬件接口设计，利用梯形图和语句表进行编程，实现了十字路口交通灯控制系统的自动化。每个路口采用LED数码管，倒计时显示，使得计时功能更加直观。关键词：西门子；PLC；交通信号灯；控制；LED；倒计时ABSTRACTSince the inception of traffic lights, its internal control system on the circuit to be continuously improved. Design began to diversity, so that even more intelligent traffic lights. Traffic control as an integral part of the traffic signals should also be suitable for the actual social situation. This is the choice making crossroads, traffic lights.Programmable Logic Controller (PLC) microprocessor core, based on commonly used electrical relay contactor control system ladder diagram compiled programming language, programming is easy, convenient features extend, modify and flexible, and simple, anti- interference ability. Siemens PLC instruction rich, you can take a variety of output, input expansion device with rich special expansion devices, including analog input devices and communications equipment is according to the traffic light control system requirements and features, the ability to easily network communication.This choice of Siemens S7-200 programmable controller as the core components, hardware interface design focuses on the use of ladder and statements table programming, a crossroads of traffic light control system automation.Each intersection with LED digital tube, countdown display, making timing more intuitive functionality.【Key Word】: siemens; PLC; traffic lights; control; LED; countdown目 录摘要IIABSTRACTIII第一章绪论11.1 引言11.2课题研究目的及意义11.3课题主要研究工作21.3本课题的主要内容2第二章 PLC的基础32.1 PLC的基础和特点32.2 PLC的结构和工作原理42.2.1 PLC的基本结构42.2.2 PLC的工作原理6第三章西门子S7-200系列PLC的硬件单元73.1主机73.1.1 CPU的主要特点73.1.2 存储系统83.2扩展单元83.3特殊功能模块93.4内部软元件103.5基本指令11第四章控制方案设计134.1技术控制要求134.2总体方案确定144.