(必威体育精装版)基于PLC的变频恒压供水系统.doc

. . 摘要 随着我国社会经济的发展,住房制度改革的不断深入,人们生活水平的不断提高,城市中各类小区建设发展十分迅速,同时也对小区的基础设施建设提出了更高的要求。小区供水系统的建设是其中的一个重要方面,供水的经济性、可靠性、稳定性直接影响到小区住户的正常生活和工作,也直接体现了小区物业管理水平的高低。传统的恒速泵加压供水,水塔高位水箱供水,气压罐供水等供水方式普遍不同程度的存在效率低、可靠性差、自动化程度不高等缺点,难以满足当前经济生活的需要。本论文针对某住宅小区的供水要求,设计了一套由PLC,变频器,多台水泵机组等主要设备构成的全自动变频恒压供水系统,主要论述了采用多泵并联供水方案的合理性,分析了多泵供水方式的各种供水状态及转换条件,分析了电机由变频转工频运行方式的切换过程,给出了实现有效状态循环转换控制的电气设计方案和PLC控制程序设计方案。 关键词：恒压供水;PLC;变频调速 ABSTRACT Along with the development of the socio—economy of our country the housing system is going deep into reforms, and peoples living standard is being impr0Ved.At the same time, in the city, each kind of sub—district construction is developing Very quickly, which puts f10rward higher requirement for the infrastructure construction of sub-district. And the construction of sub-district water supply system is an important aspect in which. The reality stability and economy of water supply directly affects sub—district household’s normal life and work, and also embodies the difference in the level of sub-district property management. The traditional means of water supply such as the pump pressurization water supply at constant speed, water tower of upper cistern, the jar etc .are hard to satisfy the needs of are economic life, because low efficiency, reliability and automation level all commonly existing in these means. according to the requirement of water supply in abiding place, a set of automatic system of constant pressure water supply by using composed variable frequency and remote monitoring and controlling, which is composed of PLC, transducer pressure electro—motors ,computer and device of communication is designed to constant that end. This paper discusses the reasonability of water supply scheme with much pump parallel connection, and analyses the conversion condition and the various states of water supply of the much pump way of water supply problem of a as well as the switch process and the problem generator from Variable frequency operation mode to work frequ