摘要

摘要
本文主要针对当前供水系统中存在的自动化程度不高、能耗严重、可靠性低的缺点加以研究，开发出一种新型的并在这三个方面都有所提高的PLC控制的恒压供水系统。

全文共分为五章。

第一章阐明了恒压供水系统的应用背景、选题意义及主要研究内容。

第二章对本系统的总体方案进行了介绍，其中包括系统的工艺要求，系统的组成和基本工作原理以及主要元器件的选型。

第三章着重写控制系统的硬件部分的基本原理。

第四章介绍了系统的软件开发工作，对PLC程序做了详细描述并介绍了过程控制中占据重要地位的PID调节原理及参数设置依据，方法。

第五章是项目调试和小结部分，给出了调试结果。

本论文综合运用了可编程控制器（PLC）、变频器、PID调节仪、传感器等现代工业控制常用的控制部件及其相关程序设计方法。

所做的研究对同类系统的研究和开发具有一定的参考价值。

关键词：可编程序控制器变频器 PID
Abstract
In the thesis, the disadvantages and problems need to be resolved of current supporting water system are briefly analyzed, and a new system, which has great advance in automation, reliability and saving energy, is studied and described.
This thesis consists of five chapters．Chapter one clarifies the application background and significance of the supporting water system and main contents of research. Chapter two introduces the overall project of the new auto－control system, including craft demand, constitution, work principle and the selection of the main electrical devices．Chapter three emphasizes the principle of the software and hardware part in control system. Chapter four, we analyze the exploitation of control system, specifying on PLC programmer and introduces the principle, parameter installation of PID control. The last chapter is the conclusion of the whole research and presents some debug result.
The research collectively utilized some modern control devices, such as PLC, frequency conversion device, sensor, and their program control method, all of these are of some reference value to the study of relative control system.
[KEY WORDS]： PLC Frequency conversion PID。