随着城市的发展，城市交通变得越来越拥挤，人们正在寻找另外方便的交通工具，而地铁的出现正恰到好处的解决了该问题，地铁的方便快捷，正成为如今最受欢迎的交通工具，因此，研究地铁系统放水系统的收集和排放，具有十分重要的理论意义和实际应用意义。
本文首先介绍了地铁的研究背景和发展现状，然后提出总体设计方案，通过对总体方案的分析，确定水池的数目和电动机的数量，进一步确定系统的硬件与软件组成，确定硬件的型号和应该使用的软件，绘制流程图来展现系统的主要工作方式，通过PLC程序进行编程控制，利用传感器的水位检测来达到放水目的，最后再对设计的系统提出改进和建议。
关键词：放水系统；自动控制；PLC；顺序控制
ABSTRACT
With the development of cities, urban transport is becoming increasingly crowded, people are looking for additional convenient means of transport, the emergence of the metro are just the right solution to the problem, subway convenient, it is now becoming the most popular means of transport Therefore, research collection and discharge subway system drainage system has very important theoretical and practical significance.
This paper introduces the background and research status subway, and then put forward the overall design scheme, by the overall scheme of analysis to determine the pool and the number of motor number, to further determine the hardware and software system components, determine the hardware type and should be used software, CAD drawing and flow chart to show the system's main work, through PLC programming control, water level is detected by the sensor to achieve the purpose of drainage, and finally suggest improvements and recommendations for the design of the system.
Key words:Drainage system;Automatic control;PLC;Sequence control
