摘要：在传统的供水系统通常存在供水压力不稳、水泵效率低等缺点从而导致水资源的浪费。随着社会的发展和进步，城市高层建筑的供水问题日益突出。一方面要求提高供水质量，不要因为压力的波动造成供水障碍；另一方面要求保证供水的可靠性和安全性。针对这两方面的要求，这就要求一种新的供水方式，这里我们采用PLC控制的恒压供水系统。该供水系统对水压实时控制性能良好，硬件模块工作稳定、可靠，达到了恒压供水系统的要求。本系统的设计是基于西门子S7-200系列PLC控制的变频供水系统，本文介绍了该控制系统的节能原理、系统构成和工作原理。通过PLC进行逻辑控制，变频器进行压力调节，PLC还能切换变频和工频，从而使得闭环自动调节恒压，进行变量供水。基本实现了高质量恒压供水、降低点电能损耗等优点。36501
毕业论文关键词： PLC，变频调速，恒压供水。
Design of intelligent building water supply system based on PLC
Abstract：In the traditional water supply system usually exists the water supply pressure instability, the low efficiency of the pump and so on, which leads to the waste of water resources. With the development and progress of the society, the water supply problem of city high-rise building is becoming more and more prominent.On the one hand, it is demanded to improve the quality of the water supply, not because of the fluctuation of the pressure caused the water supply barrier. On the other hand, the reliability and safety of the water supply are guaranteed.. In view of the two requirements, this requires a new water supply, here we use the constant pressure water supply system PLC control. The water supply system has good performance of real-time control for water pressure, and the hardware module is stable and reliable, and it can meet the requirements of constant pressure water supply system. The design of this system is based on the frequency conversion water supply system of SIEMENS S7-200 series PLC control, this paper introduces the energy saving principle, system constitution and working principle of the control system. Through PLC logic control and the pressure adjustment by inverter ,PLC can also switch frequency and power frequency, so that the closed-loop automatically adjust the constant pressure, variable water supply. It has basically realized the advantages including the high quality constant pressure water supply ,low power loss and so on.
Key Words： PLC; frequency control of motor speed; constant pressure water supply.
目  录
1绪论    1
1.1 课题背景及意义    1
1.2 变频恒压供水系统的国内外研究现状    1
1.3 本课题的主要研究内容    2
2变频技术及PLC技术简介    3
2.1变频器技术概述    3
2.1.1 变频技术简介    3
2.1.2 变频器结构分类    3
2.1.3 变频调速技术的特点及应用    3
2.2 PLC技术简介    4
2.2.1 PLC的基本概念    4
2.2.2 PLC的基本结构    4
2.2.3 PLC的工作原理    6
2.2.4 PLC应用范围    6
2.2.5 西门子S7-200系列概述    7
3系统理论分析    8
3.1 供水系统的要求    8
3.1.1 供水系统运行分析    8
3.1.2 供水系统的特性分析    8
3.1.3变频变压原理    9
3.1.4供水系统的结构    10
3.1.5 主要组成    10
3.1.6 系统总原理框图    10
4基于PLC的智能楼宇供水系统设计方案    11
4.1 系统的硬件设计    11 PLC的智能楼宇供水系统设计+梯形图:http://www.751com.cn/zidonghua/lunwen_34986.html