PLC交通灯毕业论文毕业设计.doc

PLC交通灯毕业论文 摘 要 PLC可编程序控制器是以微处理器为基础,综合了计算机技术、自动控制技术和通讯技术发展而来的一种新型工业控制装置。它具有结构简单、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。据统计,可编程控制器是工业自动化装置中应用最多的一种设备。专家认为,可编程控制器将成为今后工业控制的主要手段和重要的基础设备之一,PLC、机器人、CAD/CAM将成为工业生产的三大支柱。由于PLC具有对使用环境适应性强的特性,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,特别对多岔路口的控制可方便地实现。因此现在越来越多地将PLC应用于交通灯系统中。同时,PLC本身还具有通讯联网功能,将同一条道路上的信号灯组成一局域网进行统一调度管理,可缩短车辆通行等候时间,实现科学化管理。 关键词： PLC, 交通灯 ,程序, 报告, 设计 PLC TRAFFIC LIGHTS GRADUATION THESIS PLC programmable logic controller is a microprocessor as the foundation, a new type of intdustrial control devices integrated computer technology, automatic control technology and communication technology development and the. It has the advantages of simple structure, easy programming, high reliability, has been widely used in automatic control of industrial process and location of the. According to statistics, the programmable controller is a kind of equipment for most applications in industrial automation device. The expert thinks, the programmable controller will become one of the major means of industrial control and the important infrastructure, PLC, robotics, CAD/CAM will become the three pillar industry. PLC has the characteristics of the use of environmental adaptability, while its internal timer is very rich in resources, the progressive signal for precise control of commonly used at present, especially for the control of multi-fork can be easily achieved. So the PLC is now increasingly used in traffic lights system. At the same time, PLC communications network also has its own functions, will be the same signal on the road to form a unified LAN management, can reduce the waiting time of vehicles, the realization of scientific management. KEY WORDS: PLC , Traffic lights , Program design , Report 目　录 前　言 1 第1章 可编程控制器概况 3 1.1 PLC的发展 3 1.2 PLC的发展趋势 3 1.3 PLC的一般结构 4 1.3.2 可编程控制器的基本组成 4 1.4 PLC工作原理 7 1.5 PLC的编程语言 8 1.5.1 梯形图