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手。最初,這種控制方法主要在高壓、大功率且開關(guān)頻率較低的逆變器控制中應(yīng)用;目前被應(yīng)用于通用變頻器的控制方法的一種改進(jìn)的、適合于高開關(guān)頻率逆變器的方法。此后,日本廠商竟相研究矢量控制技術(shù),并在產(chǎn)品性能和價格兩方面取得進(jìn)展;理論界則應(yīng)用現(xiàn)代控制理論把矢量控制的理論進(jìn)一步深化,取得了解耦控制、速度觀測、參數(shù)自適應(yīng)、無速度傳感器矢量控制等方面的理論成果。20世紀(jì)80年代初,日本學(xué)者提出了基于磁通軌跡的磁通軌跡控制方法。 PLC變頻恒壓供水系統(tǒng)集變頻技術(shù)、電氣技術(shù)、現(xiàn)代控制技術(shù)于一體。 液力耦合器和電池滑差離合器調(diào)速的供水方式易漏油,發(fā)熱需冷卻,效率低,改造麻煩,只能是一對一驅(qū)動,需經(jīng)常檢修;優(yōu)點是價格低廉,結(jié)構(gòu)簡單明了,維修方便。小區(qū)供水系統(tǒng)的建設(shè)是其中的一個重要方面,供水的可靠性、穩(wěn)定性、經(jīng)濟(jì)性直接影響到小區(qū)住戶的正常工作和生活,也直接體現(xiàn)了小區(qū)物業(yè)管理水平的高低?。論文論述了采用多泵并聯(lián)供水方案的合理性,分析了多泵供水方式的各種供水狀態(tài)及轉(zhuǎn)換條件,分析了電機(jī)由變頻轉(zhuǎn)工頻運行方式的切換過程及存在的問題。系統(tǒng)有效地解決了傳統(tǒng)供水方式中存在的問題,并具有多種輔助功能,增強(qiáng)了系統(tǒng)的可靠性。摘 要 隨著我國社會經(jīng)濟(jì)的發(fā)展,住房制度改革的不斷深入,人們生活水平的不斷提高,城市中各類小區(qū)建設(shè)發(fā)展十分迅速,同時也對小區(qū)的基礎(chǔ)設(shè)施建設(shè)提出了更高的要求。本論文針對住宅小區(qū)的供水要求,設(shè)計了一套由PLC、變頻器、遠(yuǎn)傳壓力表、多臺水泵機(jī)組、計算機(jī)、通信模塊等主要設(shè)備構(gòu)成的全自動變頻恒壓供水及其遠(yuǎn)程監(jiān)控系統(tǒng),具有全自動變頻恒壓運行、自動工頻運行、遠(yuǎn)程手動控制和現(xiàn)場手動控制等功能。通過對變頻器內(nèi)置PⅢ模塊參數(shù)的預(yù)置,利用遠(yuǎn)傳壓力表的水壓反饋量,構(gòu)成閉環(huán)系統(tǒng),根據(jù)用水量的變化,采取PD調(diào)節(jié)方式,在全流量范圍內(nèi)利用變頻泵的連續(xù)調(diào)節(jié)和工頻泵的分級調(diào)節(jié)相結(jié)合,實現(xiàn)恒壓供水且有效節(jié)能。關(guān)鍵詞:恒壓供水;PLC;變頻調(diào)速AbstractAlong with the development of the socio—economy of our count,the housing system is going deep into reforms,and people’s living standard is being improved.At the same time,in the city,each kind of sub—district constmction is developing very quickly,which puts forrward higher requirement for the infrastru construction of subdistrict.And the construction of subdistrict water supply system is an important aspect in which.The reliability,stability and economy of water supply directly affects sub—district Households nomal life and work,and also embodies the difference in the level of subdistrict property management.The traditional means of water supply such as the pump pressurization water supply at constant speed,water tower of upper cistem,the jaretc. are hard to satisfy the needs of current economic life, because low efficiency,reliability and automation level are all monly existing in these means.According to the requirement of water supply in a abiding place,a set of automatic system of constant pressure water supply by using variable frequency and remote monitofing and rolling,wrhich is posed of PLC,transducer,pressure sensor,pumps and electro—motors,puter and device of munication is designed to that end.This set of system has the functions like automatic constant pressure operation by using variable frequency,automatic work frequency operation,and the function of longrange conrol by hand and the onthe—spot control by hand etc.The system has solved efficiently the problem existing in the traditional way of water supply,which has various supplementary functions to strengthen the reliability.The system has an organic bination with puter and promotes the systematic overall performance.Based on that the three side of the pump water delivery rate and the pump rotational speed bee direct ratio,the paper analyses the mechanism of energy saving that the way of water supply by using the method of variable velocity variable frequency is superior to the traditional way of constant pressure water supply controlled by valve. Setting up in advance the parameter of the PH modular builtin the transducer,a system of closed circuit using the feedback of hydraulic pressure of far.biograhy pressure table has formed.According to the change of water consumption,with PID,in the sphere of whole rate of now bining the constant regulation of the pump offrequency conversion with the work frequency pump grade regulation,the system of closed circuit can realize the constant pressure water supply and save energy efficiently. 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 as well as the switch process and the problem of a generator from variable frequency operation mode to work frequency operation mode. This paper has also given the electrical design scheme and PLC controlling program scheme that realizes effective state circulating conversion control. By researching the munication agreement between the puter and PLC,this paper has finished setting up the munication between upper and lower puter,and also has described the method to pile puter monitoring program to realize the long—range monitoring and fault reporting for water supply system through munication modular Key words:Constant pressurewatersupply;PLC;Variable velocity variable frequency; Constant pressurewatersupplyKey words:Constant presrewater supply;PLC;Variable Velocity Variable fequency;Constant pressurewatersupply目 錄摘 要 1Abstract 2第一章 緒 論 6 課題背景及意義 6 國內(nèi)外變頻調(diào)速技術(shù)的發(fā)展與現(xiàn)狀 7 可編程控制器(PLC)的特點及應(yīng)用 8 變頻恒壓供水系統(tǒng)特點及其安全性討論 13 本課題的主要研究內(nèi)容 14第2章 系統(tǒng)的理論分析及方案的確定 15 變頻恒壓供水系統(tǒng)理論分析 15 變頻恒壓供水系統(tǒng)節(jié)能原理 15 變頻恒壓控制的理論模型 17 變頻恒壓供水系統(tǒng)的近似數(shù)學(xué)模型 182.2 變頻恒壓供水系統(tǒng)控制方案的確定 18 供水系統(tǒng)的控制流程及其控制流程圖 18 供水系統(tǒng)中水泵切換條件分析 26 本章小結(jié) 29第三章 變頻恒壓供水系統(tǒng)的硬件設(shè)計 30 系統(tǒng)主要配置的選型 30 水泵機(jī)組的選型 30 變頻器的選型 31 PLC及其擴(kuò)展模塊的選型 33 壓力變送器及數(shù)顯儀的選型 34 繼電器,軟啟動器的選型 35 系統(tǒng)主電路分析及設(shè)計 35 系統(tǒng)控制電路分析及設(shè)計 37 可編程邏輯控制器(PLC)的I/0端子分配 38 變頻器接線及功能的設(shè)定 40 本章小結(jié) 41第四章 變頻恒壓供水系統(tǒng)的軟件設(shè)計 42 系統(tǒng)水泵運行狀態(tài)及轉(zhuǎn)換過程分析 42 PLC程序設(shè)計方法的分析 44 系統(tǒng)控制程序設(shè)計 47 變頻器P l D控制功能參數(shù)的設(shè)置 51 PID控制及其控制算法 51 恒壓供水PID調(diào)節(jié)過程分析 53 變頻器PID控制參數(shù)的設(shè)置 53 可靠性分析 55 本章小結(jié) 55第五章 變頻恒壓供水遠(yuǎn)程監(jiān)控系統(tǒng)的設(shè)計 57 S7200系列PLC的監(jiān)控方法 57 本系統(tǒng)計算機(jī)監(jiān)控內(nèi)容及原理圖 57 本章小結(jié) 59第六章 結(jié) 論 60 本課題研究結(jié)論 60 課題存在問題與展望 60參考文獻(xiàn) 61外文翻譯 62致 謝 86附 錄 87第一章 緒 論 課題背景及意義 眾所周知,水是人類生活、生產(chǎn)中不可缺少的重要物質(zhì),在節(jié)水節(jié)能已成為時代特征的現(xiàn)實條件下,我們這個水資源和電能短缺的國家,長期以來在市政供水、高層建筑供水、工業(yè)生產(chǎn)循環(huán)供水等方面技術(shù)一直比較落后,自動化程度低,而隨著我國社會經(jīng)濟(jì)的發(fā)展,人們生活水平的不斷提高,以及住房制度改革的不斷深入,城市中各類小區(qū)建設(shè)發(fā)展十分迅速,同時也對小區(qū)的基礎(chǔ)設(shè)施建設(shè)提出了更高的要求。 氣壓罐供水具有體積小、技術(shù)簡單、不受高度限制等特點,但此方式調(diào)節(jié)量小、水泵電機(jī)為硬起動且起動頻繁,對電器設(shè)備要求較高、系統(tǒng)維護(hù)工作量大,而且為減少水泵起動次數(shù),停泵壓力往往比較高,致使水泵在低效段工作,而出水壓力無謂的增高,也使浪費加大,從而限制了其發(fā)展。目前的供水方式朝向高效節(jié)能、自動可靠的方向發(fā)展,變頻調(diào)速技術(shù)以其顯著的節(jié)能效果和穩(wěn)定可靠的控制方式,在風(fēng)機(jī)、水泵、空氣壓縮機(jī)、制冷壓縮機(jī)等高能耗設(shè)備上廣泛應(yīng)用,特別是在城鄉(xiāng)工業(yè)用水的各級加壓系統(tǒng),居民生活用水的恒壓供水系統(tǒng)中,變頻調(diào)速水泵節(jié)能效果尤為突出,其優(yōu)越性表現(xiàn)在:一是節(jié)能顯著;二是在開、停機(jī)時能減小電流對電網(wǎng)的沖擊以及供水水壓對管網(wǎng)系統(tǒng)的沖擊;三是能減小水泵、電機(jī)自身的機(jī)械沖擊損耗。1964年,最先提出把通信技術(shù)中的脈寬調(diào)制P刪技術(shù)應(yīng)用到交流傳動中的是德國人。1980年,德國人在應(yīng)用微處理器的矢量控制研究中取得了進(jìn)展,促進(jìn)了矢量控制的實用化。這種方法不需