摘要随着社会经济与科技的较快发展，工业的自动化程度也随之攀升。可是国内供水行业的科研发展长期以来都处于相对滞后的程度，身处于节水减排的时代背景下，我们不得不抛弃传统的供水方式，在城市居民用水等方面谋求改革与发展。因此综合国内住宅小区的供水需求，本文设计了一套基于PLC的变频恒压供水组态监控系统。86019

变频恒压供水系统可分成两部分：上位机实时监控，下位机通过可编程控制器实现水泵机组变频控制。上位机的组态软件可实现动、静态监控，同时具有显示、报警、数据实时刷新等功能。下位机由可编程控制器、水泵机组以及变频器构成。在本设计中水泵机组包含三台水泵电机，它们互相采用变频循环运行模式，通过变频器的调节实现水泵机组的起动和变频调速功能，在运行切换过程中坚持“先启先停”的原则。在实验室完成了上述两部分的设计及模拟调试，效果较好。

毕业论文关键词：恒压供水 ；变频 ；PLC ；组态王

Abstract With the rapid development of social economy and science and technology, industrial automation also rose。 But the development of the domestic water supply industry has long lagged behind in degree, under the background of the body in water-saving and emission reduction, we had to abandon the traditional way of water supply, seeking reform and development in the urban water and so on。 Therefore, integrated water demand in the domestic residential area, a set of constant pressure water supply configuration monitoring system based on PLC is designed in this paper。

Constant pressure water supply system can be pided into two parts: the PC real-time monitoring, the next crew to achieve frequency control water pump via the programmable controller。 PC configuration software enables dynamic and static monitoring and also have display, alarm, real-time data refresh function。 Lower machine consists of a programmable controller, a water pump unit and a frequency converter。 In the design of the pump unit contains three pump motor,each other by frequency conversion cycle operating mode, through the adjustment of the frequency converter realize pump unit of starting and frequency control function, in the operation of switching process adhere to the “start first stop” principle 。The design and simulation of the above two parts are completed in the laboratory, and the results are good。

Keywords: constant pressure water supply;frequency conversion;PLC;kingview

目录

第一章 绪论 1

1。1 课题背景及其意义 1

1。2 变频恒压供水系统在国内外的研究现状 2

1。3 变频恒压供水系统的特点 2

1。4 本文主要研究内容 3

第二章 变频恒压供水系统的理论分析及方案制定 5

2。1 变频恒压供水系统的理论分析 5

2。1。1 电机的调速工作原理 5

2。1。2 水泵的调节原理 6

2。2 变频恒压供水系统的方案制定 8

2。2。1 供水系统的控制流程 8

2。2。2 供水系统中水泵的切换条件 10

2。3 本章小结 11

第三章 变频恒压供水系统的PLC控制 12

3。1 PLC的选型 12

3。2变频器的选型