摘要当今社会由于工业的发展和人们生活水平的显著提高，导致用水量的增加，然而水资源的总量是有限的，造成了用水紧张。由于城市水平的发展的加速，城市中人民大都是购买生活小区来居住的，因为关系着居民的生活，那么在城市中小区的供水就显得十分的重要了。46512
本系统是针对供水泵站而设计的一套由PLC、变频器、水泵机组等设备组成的自动恒压变频供水系统。为了满足各方面的需要，我们结合了PLC、传感器和变频器让其发挥各自的优势，这样不仅具有节能的效果，而且能够使系统稳定的运行，同时我们还根据自己的要求设置变频器中的PID的参数，再由压力传感器反馈水压的变化，如果水压变化了就可以用PID模块调节水泵以此来实现供水的恒定。这篇文章先是对比了变频调速供水和传统的供水，发现其优缺点；其次，分析每个泵的转化的条件，工作的状态以及他的切换的方式，以此来研究出恒压供水的方案，并且要自己设计出硬件、控制程序、电路图和控制电路。
通过对本次学习利用PLC和变频器设计系统的设计理念，为以后系统的设计和应用奠定扎实基础。
毕业论文关键词：PLC、恒压变频、PID、供水
Abstract In today's society due to the development of the industry and the significant increase of people's living standard, lead to the increase of water consumption, the amount of water resources is limited, however, caused by water stress.Due to the acceleration of the development of the city, the people are mostly buy living community in the city to live, because the relationship between the people's life, village in the city's water supply is very important.
This system is designed for water supply pump station set by PLC, inverter, pump equipment of automatic constant pressure frequency conversion water supply system.In order to meet the needs of all aspects, we combined with PLC, sensor and transducer to play their respective advantages, not only has the effect of energy saving, but also can make the system stable running, at the same time we also according to the requirements of their setting of PID parameters of the frequency converter, again by the change of the hydraulic pressure sensor feedback, if the pressure changes can use PID module to adjust the water pump in order to achieve the constant water supply.This article first compares the frequency control water supply and the traditional water supply, found their advantages and disadvantages;Second, the analysis of each pump conversion conditions, work status, and his way of switching, in order to study the constant pressure water supply plan, and to design the hardware and control procedures, circuit diagrams and control circuit.
By using PLC and frequency converter design system for the study of the design concept, lay solid foundations for the system design and application.
Key words:PLC, Constant pressure frequency conversion, PID, The water supply
目  录
第一章 绪论    1
1.1课题意义    1
1.2恒压供水的研究现状    1
1.2.1国内研究现状    1
1.2.2系统的比较    2
1.3本课题的设计方案    2
1.3.1系统的总体布局    3
1.3.2系统总体方案    3
1.3.3系统的特点    4
1.4本课题的主要工作    4
第二章 恒压供水系统的方案    5
2.1系统的基本构成    5
2.2变频器    5
2.2.1 变频器简介    5
2.2.2变频器的配线图    6
2.3系统的软启动    8
2.3.1软启动的原理以及特点    8
2.3.2 软启动的启动方式    9 PLC恒压变频供水系统电气系统设计+梯形图:http://www.751com.cn/zidonghua/lunwen_48233.html