第一篇：恒壓供水中英文簡(jiǎn)介

摘要

隨社會(huì)經(jīng)濟(jì)的迅速發(fā)展，人們對(duì)供水質(zhì)量和供水系統(tǒng)可靠性的要求不斷提高，再加上目前能源緊缺，利用先進(jìn)的自動(dòng)化技術(shù)、控制技術(shù)以及通訊技術(shù)，設(shè)計(jì)高性能、高節(jié)能、能適應(yīng)不同領(lǐng)域的恒壓供水系統(tǒng)成為必然趨勢(shì)。

本設(shè)計(jì)是針對(duì)居民生活用水/消防用水而設(shè)計(jì)的。由變頻器、PLC及PID調(diào)節(jié)器組成控制系統(tǒng)，調(diào)節(jié)水泵的輸出流量。電動(dòng)機(jī)泵組由三臺(tái)水泵并聯(lián)而成，由變頻器或工頻電網(wǎng)供電，根據(jù)供水系統(tǒng)出口水壓和流量來控制變頻器電動(dòng)機(jī)泵組之間的切換及速度，使系統(tǒng)運(yùn)行在最合理的狀態(tài)，保證按需供水。

本文介紹了采用PLC控制的變頻調(diào)速供水系統(tǒng)，由PLC進(jìn)行邏輯控制，由變頻器進(jìn)行壓力調(diào)節(jié)。在經(jīng)過PID運(yùn)算，通過PLC控制變頻與工頻切換，實(shí)現(xiàn)閉環(huán)自動(dòng)調(diào)節(jié)恒壓供水。運(yùn)行結(jié)果表明，該系統(tǒng)具有壓力穩(wěn)定，結(jié)構(gòu)簡(jiǎn)單，工作可靠等優(yōu)點(diǎn)。

關(guān)鍵詞：變頻調(diào)速 ； 恒壓供水； PID調(diào)節(jié)； PLC

ABSTRACT

With the rapid development of social economy, it demands the better of water supply' s quality and reliability of water supply system.Meanwhile energy resources are seriously lack.So it is inevitable tendency to design water supply system which has high function and saves on energy well, with help of advanced technique of automation, control and communication.At the same time this system can adapt different water supply fields.It is very important of the Water Supply System in Constant Pressure for the water supply in industrial and citizen existence.It is consist of the variable frequency and speed regulation, PLC, PID control system for the control system.It controls the outcome of the pumps.The generator pumps are consist of parallel three pumps, and the power come from variable frequency and speed regulation or power grid.According to the water supply of constant pressure’s outcome water press and flux, the control system control the variable frequency and speed regulation, parallel pumps’ speed and cut over, cause the system move in the best rational situation, assure according to wants supply water.This design has many merits such as save energy.In this paper, the control principle of VVVF providing-water system is introduced, PLC is used to carry on logic control and invertered to modulate pressure．Through PID control principle.We realize Closed-loop control in VVVF Providing-water System.The result indicates that the system has the stable pressure, simple structure, and reliable work.Keywords： variable frequency and speed regulation； water supply of constant pressure； PID control system； PLC

第二篇：英文簡(jiǎn)介

我叫李永亮。首先，我在2010年畢業(yè)于大連工業(yè)大學(xué)服裝設(shè)計(jì)專業(yè)，畢業(yè)后在大楊創(chuàng)世股份有限公司從事銷售行業(yè)，工作了1年時(shí)間。我很喜歡大連，這也是我畢業(yè)后決定留在大連的原因，但是，這個(gè)城市這個(gè)工作，都是比較安逸的，作為年輕人，應(yīng)該不斷的去奮斗，不應(yīng)該提前享受安逸的生活，所以我選擇來北京發(fā)展，這里的壓力會(huì)大一些，同樣，動(dòng)力也會(huì)大一些，因?yàn)槟悴慌ぷ鞯脑?，那么你就將?huì)被淘汰，因此，我會(huì)很用心很努力的對(duì)待我的工作！

My name is Li Yongliang.First of all, I graduated in 2010 at the Dalian

University clothing design special field, after graduation DaYangChuangShi limited company in sales, working for 1 years.I very like Dalian, this is my

graduation decided to stay in Dalian reasons, however, the city of the work, are relatively comfort, as a young man, should continue to struggle, should not to enjoy the easy life, so I choose to come to Beijing to develop, the pressure will be greater, similarly, power will be larger, because you don't work hard, you will be eliminated, therefore,I will be very hard very hard to deal with my work!

我是一個(gè)很隨和的人，平時(shí)很容易相處，很愛交朋友，在生活上，只要平淡簡(jiǎn)單點(diǎn)就行，但必須經(jīng)過現(xiàn)實(shí)考驗(yàn)。對(duì)待工作很認(rèn)真，如果是我喜歡的工作而且這個(gè)職位還有上升的空間，我會(huì)很用心很努力的走到那個(gè)位置，為了生活的更好，必須得努力去工作。

I am a easy going person, usually very easy to get along with, love to make friends, in life, as long as Insipid and simple point on the line, But to must pass the test of reality.Works very seriously, if I like the work and this position also increased the space, I will be very hard very hard to get to this position, In order to live better, must work hard

4年的服裝設(shè)計(jì)學(xué)習(xí)，讓我對(duì)服裝時(shí)尚很敏感，做過一年的職業(yè)裝銷售，我對(duì)服裝的店面銷售，與客戶的需求分析，店面陳列，貨品管理，售后服務(wù)等都有了一個(gè)全面的認(rèn)知years of fashion design learning, let I to fashion very sensitive, Done a year occupation installed sales, Make me to high-end clothing store sales and customer demand analysis, store display, merchandise management, after-sales service and have a comprehensive understanding of

第三篇：PLC 變頻調(diào)速技術(shù)在泵站恒壓供水中應(yīng)用

PLC 變頻調(diào)速技術(shù)在泵站恒壓供水中應(yīng)用

0 引言

供水系統(tǒng)是國(guó)民生產(chǎn)生活中不可缺少的重要一環(huán)。傳統(tǒng)供水方式占地面積大，水質(zhì)易污染，基建投資多，而最主要的缺點(diǎn)是水壓不能保持恒定，導(dǎo)致部分設(shè)備不能正常工作。變頻調(diào)速技術(shù)是一種新型成熟的交流電機(jī)無極調(diào)速技術(shù)，它以其獨(dú)特優(yōu)良的控制性能被廣泛應(yīng)用于速度控制領(lǐng)域，特別是供水行業(yè)中。由于安全生產(chǎn)和供水質(zhì)量的特殊需要，對(duì)恒壓供水壓力有著嚴(yán)格的要求，因而變頻調(diào)速技術(shù)得到了更加深入的應(yīng)用。恒壓供水方式技術(shù)先進(jìn)、水壓恒定、操作方便、運(yùn)行可靠、節(jié)約電能、自動(dòng)化程度高，在泵站供水中可完成以下功能：(1)維持水壓恒定；(2)控制系統(tǒng)可手動(dòng)/自動(dòng)運(yùn)行；(3)多臺(tái)泵自動(dòng)切換運(yùn)行；(4)系統(tǒng)睡眠與喚醒。當(dāng)外界停止用水時(shí)，系統(tǒng)處于睡眠狀態(tài)，直至有用水需求時(shí)自動(dòng)喚醒；(5)在線調(diào)整PID參數(shù)；(6)泵組及線路保護(hù)檢測(cè)報(bào)警，信號(hào)顯示等。

將管網(wǎng)的實(shí)際壓力經(jīng)反饋后與給定壓力進(jìn)行比較，當(dāng)管網(wǎng)壓力不足時(shí)，變頻器增大輸出頻率，水泵 轉(zhuǎn)速加快，供水量增加，迫使管網(wǎng)壓力上升。反之水泵轉(zhuǎn)速減慢，供水量減小，管網(wǎng)壓力下降，保持恒壓供水。系統(tǒng)硬件構(gòu)成系統(tǒng)采用壓力傳感器、PLC和變頻器作為中心控制裝置，實(shí)現(xiàn)所需功能。

安裝在管網(wǎng)干線上的壓力傳感器，用于檢測(cè)管網(wǎng)的水壓，將壓力轉(zhuǎn)化為4～20 mA的電流信號(hào)，提供給PLC與變頻器。

變頻器是水泵電機(jī)的控制設(shè)備，能按照水壓恒定需要將0～50 Hz的頻率信號(hào)供給水泵電機(jī)，調(diào)整其轉(zhuǎn)速。ACS變頻器功能強(qiáng)大，預(yù)置了多種應(yīng)用宏，即預(yù)先編置好的參數(shù)集，應(yīng)用宏將使用過程中所需設(shè)定的參數(shù)數(shù)量減小到最小，參數(shù)的缺省值依應(yīng)用宏的選擇而不同。系統(tǒng)采用PID控制的應(yīng)用宏，進(jìn)行閉環(huán)控制。該宏提供了6個(gè)輸入信號(hào)：?jiǎn)?dòng)/停止(DI1、DI5)、模擬量給定(AI1)、實(shí)際值(AI2)、控制方式選擇(DI2)、恒速(DI3)、允許運(yùn)行(DI4)；3個(gè)輸出信號(hào)：模擬輸出(頻率)、繼電器輸出1(故障)、繼電器輸出2(運(yùn)行)；DIP開關(guān)選擇輸入0～10 V電壓值或0～20 mA電流值(系統(tǒng)采用電流值)。變頻器根據(jù)給定值A(chǔ)I1和實(shí)際值A(chǔ)I2，即根據(jù)恒壓時(shí)對(duì)應(yīng)的電壓設(shè)定值與從壓力傳感器獲得的反饋電流信號(hào)，利用PID控制宏自動(dòng)調(diào)節(jié)，改變頻率輸出值來調(diào)節(jié)所控制的水泵電機(jī)轉(zhuǎn)速，以保證管網(wǎng)壓力恒定要求。

根據(jù)泵站供水實(shí)際情況與需求，利用一臺(tái)變頻器控制3臺(tái)水泵，因此除改變水泵電機(jī)轉(zhuǎn)速外，還要通過增減運(yùn)行泵的臺(tái)數(shù)來維持水壓恒定，當(dāng)運(yùn)行泵滿工頻抽水仍達(dá)不到恒壓要求時(shí)，要投入下一臺(tái)泵運(yùn)行。反之，當(dāng)變頻器輸出頻率降至最小，壓力仍過高時(shí)，要切除一臺(tái)運(yùn)行泵。所以不僅需要開關(guān)量控制，還需數(shù)據(jù)處理能力，采用FX－4AD(4模擬量入)獲得模擬量信號(hào)。它在應(yīng)用上的一個(gè)重要特征就是由PLC自動(dòng)采樣，隨時(shí)將模擬量轉(zhuǎn)換為數(shù)字量，放在數(shù)據(jù)寄存器中，由數(shù)據(jù)處理指令調(diào)用，并將計(jì)算結(jié)果隨時(shí)放在指定的數(shù)據(jù)接觸器中。通過其可將壓力傳感器電流信號(hào)和變頻器輸出頻率信號(hào)轉(zhuǎn)換為數(shù)字量，提供給PLC[1>，與恒壓對(duì)應(yīng)電流值、頻率上限、頻率下限(考慮到水泵電機(jī)在低速運(yùn)行時(shí)危險(xiǎn)，必須保證其頻率不低于20Hz，因此頻率上限設(shè)為工頻50Hz，下限設(shè)為20Hz)進(jìn)行比較，實(shí)現(xiàn)泵的切換與轉(zhuǎn)速的變化。

系統(tǒng)在設(shè)計(jì)時(shí)應(yīng)使水泵在變頻器和工頻電網(wǎng)之間的切換過程盡可能快，以保證供水的連續(xù)性，水壓波動(dòng)盡可能小，從而提高供水質(zhì)量。但元件動(dòng)作過程太快，會(huì)有回流損壞變頻器。為了防止故障的發(fā)生，硬件上必須設(shè)置閉鎖保護(hù)，即1Q與4Q，2Q與5Q，3Q與6Q不能同時(shí)閉合。系統(tǒng)軟件設(shè)計(jì)

控制系統(tǒng)軟件是指用梯形圖語言編制的對(duì)3臺(tái)泵進(jìn)行控制的程序。它對(duì)3臺(tái)泵的控制，主要解決 系統(tǒng)的手動(dòng)及自動(dòng)切換、各元件和參數(shù)的初始化、信號(hào)及通訊數(shù)據(jù)的預(yù)處理、3臺(tái)泵的啟動(dòng)、切換及停止的條件、順序、過程等問題。

當(dāng)變頻器輸出頻率達(dá)到頻率上限，供水壓力未達(dá)到預(yù)設(shè)值時(shí)，發(fā)出加泵信號(hào)，投入下1臺(tái)泵供水。當(dāng)供水壓力達(dá)到預(yù)設(shè)值，變頻器輸出頻率降到頻率下限時(shí)，發(fā)出減泵信號(hào)，切除在工頻運(yùn)行方式中的1臺(tái)泵。系統(tǒng)剛啟動(dòng)時(shí)，情況簡(jiǎn)單，首先啟動(dòng)一號(hào)泵即可。但考慮3臺(tái)泵聯(lián)合運(yùn)行時(shí)情況復(fù)雜，任1臺(tái)或2臺(tái)泵可能正在工頻自動(dòng)方式下運(yùn)行，而其他泵則可能在變頻器控制下運(yùn)行，因此必須預(yù)先設(shè)定增減水泵的順序。即獲得加泵信號(hào)后，按照1號(hào)泵、2號(hào)泵、3號(hào)泵的順序優(yōu)先考慮。獲得減泵信號(hào)后，按照3號(hào)泵、2號(hào)泵、1號(hào)泵的順序優(yōu)先考慮。

為了防止故障的發(fā)生，軟件上也必須設(shè)置保護(hù)程序，保證1Q與4Q、2Q與5Q、3Q與6Q不能同時(shí)閉合。在加減泵時(shí)必須設(shè)置元件動(dòng)作順序及延時(shí)，防止誤動(dòng)作發(fā)生。

考慮到系統(tǒng)工作環(huán)境對(duì)運(yùn)行狀態(tài)的影響，在設(shè)計(jì)中采用硬件、軟件上的雙重濾波來消除干擾的影響。硬件上變頻器提供了濾波時(shí)間常數(shù)，當(dāng)模擬輸入信號(hào)變化時(shí)，63％的變化發(fā)生在所定義的時(shí)間常數(shù)中；軟件上采用數(shù)字濾波的方式，系統(tǒng)采用平均值的方法[2>。

計(jì)算最近10次采樣的平均值，其計(jì)算公式如下：系統(tǒng)參數(shù)的確定

系統(tǒng)變頻運(yùn)行主要靠變頻器來實(shí)現(xiàn)。變頻器有一數(shù)量很大的參數(shù)群，初始情況下，只有所謂的基本參數(shù)可以看到。只需設(shè)定簡(jiǎn)單的幾個(gè)參數(shù)，變頻器就可以工作。

除基本參數(shù)外，還必須對(duì)完整參數(shù)進(jìn)行設(shè)定。

完整參數(shù)的設(shè)定主要是PID參數(shù)的整定，它是按照工藝對(duì)控制性能的要求，決定調(diào)節(jié)器的參數(shù)Kp，TI，TD?？刂票磉_(dá)式為：

變頻器根據(jù)偏差調(diào)節(jié)PID的參數(shù)，當(dāng)運(yùn)行參數(shù)遠(yuǎn)離目標(biāo)參數(shù)時(shí)，調(diào)節(jié)幅度加快，隨著偏差的逐步接近，跟蹤的幅度逐漸減小，近似相等時(shí)，系統(tǒng)達(dá)到一個(gè)動(dòng)態(tài)平衡，維持系統(tǒng)的恒壓穩(wěn)定狀態(tài)[

3、4>。試驗(yàn)結(jié)果

由于系統(tǒng)的顯示和通訊功能，可以對(duì)系統(tǒng)工作情況進(jìn)行監(jiān)測(cè)?？紤]到管網(wǎng)覆蓋面積大，泵站海拔高度相對(duì)低，遠(yuǎn)端供水壓力需維持3kg，因此泵站出水口壓力必須維持5kg。試驗(yàn)條件為管網(wǎng)初始無壓 力，電磁閥控制一定量相同用水情況下啟動(dòng)系統(tǒng)。獲得的數(shù)據(jù)經(jīng)MATLAB進(jìn)行插值擬合可得系統(tǒng)在不同條件下跟蹤壓力變化的曲線[5>。

試驗(yàn)記錄的數(shù)據(jù)顯示，系統(tǒng)在未進(jìn)行濾波和PID控制時(shí)，響應(yīng)速度特別慢、誤差大、振蕩嚴(yán)重，見圖5。在未進(jìn)行濾波而引入數(shù)字PID控制時(shí)，響應(yīng)速度明顯加快，但振蕩問題未能得到解決，這是由于喘振現(xiàn)象的存在；當(dāng)管道壓力與設(shè)定值近似相當(dāng)時(shí)，水錘效應(yīng)影響明顯，壓力波動(dòng)異常，PID的參數(shù)跟蹤整定，形成惡性循環(huán)，管道中空氣的存在也會(huì)導(dǎo)致振蕩問題。

該系統(tǒng)是按照工業(yè)生產(chǎn)需求設(shè)計(jì)的，實(shí)現(xiàn)了預(yù)定的一系列功能，保證了系統(tǒng)的穩(wěn)定和安全性，在長(zhǎng)時(shí)間運(yùn)行中取得了良好的效果。只需作相應(yīng)修改就可推廣到相關(guān)供水系統(tǒng)中。

第四篇：基于PLC的恒壓供水系統(tǒng)設(shè)計(jì) 英文資料

Constant Pressure Water Supply System Based plc

Abstract: Based one simple analysis of the methods for water supply used domestically and abroad, this paper discusses the principle and system’s structure of automatic water supply system by using frequency conversion speed regulation in detail.Then the system’s advantages are discussed and some key problems that should be pay attention to designing are presented.Keyword: Frequency conversion speed regulation;water supply with stable pressure: PID regulator.1、Foreword

At present, supply water in residential area and life of the skyscraper of our country generally adopt the way common frequently.It has heavy energy consumption, high noise, and there has a great deal of questions in the source of water, such as secondary pollution etc.And it is a kind of comparatively ideal mode to adjust the water supply device controlled rapidly with frequency conversion.Entering the middle and later periods of the 1990s, as the speed technology of frequency conversion achieves more development becomes perfect, the way of the full-automatic constant pressure that based on this technology supplied water has already been widely used in the developed country, and is becoming riper.In recent years, authors has made some real work on rapidly to the transformation in frequency conversion supply water design and construction of control system, have accumulated some experience, and has formed the view on some questions.The reason why the energy-conserving principle frequency conversion of the water pump system of speed adjustment becomes popularized , is mainly because that it has a better energy-conserving result.To pump system of frequency conversion, the water pump after adjusting the speed has functional relation of the following:

Q1/Q2 =n1/n2

(1)H1/H2 =(n1/n2)2(2)of the type.Q1, Q2 represents the flow before and after the speed for the water pump respectively;N1, n2 represents the rotational speed before and after the speed for the water pump respectively;H1, H2 represents the lift before and after the speed for the water pump respectively.According the above: H1/H2 =(f1/f2)2.Namely real lift of a water pump is power the square of frequency in direct radio.Therefore changing the power supply frequency of the electrical machinery of water pump through the frequency converter can control supporting water pressure strength of the water pump.2 constant pressures as Fig.1 shows supply water of the automatically controlled frequency conversion water-supply system principle block diagram.P1 is the give pressure value, p2 for the actual pressure value had examined from the pipeline of the pressure sensor, PID regulator passes the error operation of the two value, and through controlling the frequency output of the frequency converter, thus make the pressure of the pipeline remain throughout on establishing value p1.This system can measure users' instantaneous water pressure adjust automatically , regulate the amount of quantity of supplying water and operation conditions of the electrical machinery in view of the above.Can according to give water pressure strength to set for and control pressure value which needed , make the equipment in the constant pressure state all the time, can know from load characteristic of electrical machinery axle power and its the third power of in direct radio rotational speed of electrical machinery mixed, that is p1/p2=(n1/n2)3.For example, as the frequency converter output frequency for 35Hz(establish as 50Hz at most), that is to say that the actual rotational speed is 70% o'clock of specified rotational speed, the power consumption of the governor is 0.73 =0.343, account for specified 35%.That is to say , the water pump is always in constant pressure and turn the working state of matching the way into the flow , is it is it keep to exceed to dispel and backset current have work loss.Constant speed transfer with frequency conversion speed axle power change curve as Fig.2 shows , relatively can know, it is the most obvious that frequency conversion adjusts the energy-conserving result of speed way.2、Case analyses

Constant pressure is it regulate flow of water to the purpose to up to constant pressure through suiting well rapidly in frequency conversion to supply water, the goal that it controls finally is the water pressure.Controlling the target has non-linear, lagging characteristics.The quality of PID regulator performance , has determined the quality of the water-supply system to a great extent When the system is during the course of starting and stopping, or the pressure establishing value changes by a large margin , because there is a very great deviation within short time, no matter the control algorithm of PID regulator adopts the increment type or the position type, its total mark one will fetch the cistern , water pump group and complement the fittings to form relevantly.The core of this system is that frequency conversion adjusts the speed switch board, it monitors the pressure of the pipe network in real time through the pressure sensor, and change into the electric signal and offer the frequency converter to make operation, through the controlling commonly of frequency converter, programmable controller PLC and relay array, adjust the system of supplying water rapidly after forming perfect full-automatic frequency conversion.Frequency converter is various in kinds, for instance the types, such as Mitsubishi, Fuji, three Kenya and ABB, etc.Generally often select the pumps, special-purpose series of air blower for use.Whether take Mitsubishi FR-A140E as an example, it except general function had of brand , there are the following characteristics : The inside adopts the intellectual power module of IPM, it is lowest to make the noise of the electrical machinery to reduce;Frequency converter, and work-frequency power can is it switch over to go on frequently, user is it is it start , stop through PLC and switch over the order automatically to input to need only, can conveniently through to lock movement switch over different water pump each other contactor, and does not need to design the tedious control procedure by oneself like the thing that in the past , this is one of this peculiar functions of frequency converter;Built-in instantaneous power cut starts and retries and starts the function , in a situation that nobody guarded, even if can be started by oneself after the frequency converter shuts down, totally realize with the operation of the automatic way.PID regulator available frequency converter of system this built-in value very heavy, this will store deviation in regulates.During the process of dispelling the deviation to regulate, must lead to the fact the system and present greater ultra mediation long-time vibration, can produce the serious integration saturation phenomenon also at the same time, thus influence the normal running of the equipment.Is it drop the influence to most low to want , should adopt PID control method that integration separate among controlling algorithm, in order to reach the anticipated result.After dealing with like this, can shorten the system and reach steady transition course time greatly System allocate two 11kW water pump support 600 over resident water.Two pump offer large peak flow most when working at the same time, single platform meet the small flow and supply water at night.In addition all water pumps can run by way of frequency conversion, can circulate way soft to start, in this way, can reduce the impact to the electric wire netting and pipe network.What merits attention is two pump when frequency conversion and worker are switched over frequently, have procedure it locks to be enough each other only, outputting must adopt machinery to interlock the contactor, can avoid the situation that two contactors close at the same time in the twinkling of an eye in this way, so as not to short out in twinkling of an eye causing power.Pressure sensor P monitors the size of the water pressure signal in real time, the signal is dealt with by PID, input it to the frequency converter.At the small flow, water pump electrical machinery 1M turn round(whether 1KM1 is it shut to suck), and through feedback password change his rotational speed constantly, it is invariable in order to keep the pressure;In case of large flow , compare frequency conversion by pressure circuit send out through PLC “ constant/changed switch over frequently” “ operate and interlock ” the order, machinery interlocks the contactor(2KM2 in 2KM(2KM1 +2KM2), contactor 3KM have the electricity.At this moment, electrical machinery 2M is started by way of frequency conversion, 1M is switched over and run at full speed frequently to run.In this way, this system can maintain water consumption on a invariable pressure all the time.Built up in the aforesaid district initial stage, supply water and adopt the way frequently of workers, because of energy consumption being heavy dependability is bad, the household reflects strongly.Use instead after frequency conversion supply water, installation total capacity reduce 25% than original equipment, economize on electricity the index is close 30% synthetically actually, the result is remarkable.3、Several questions while apply are in case of great majority

The environment for use of the scene is comparatively abominable.Though frequency converter has very strong protection functions itself, such as owe keep , excessive pressure , is it flow to pass, electric current amplitude limiting is it make exactly to choose, overload, overheated lacking looking , shorting out and disconnected ink protect the function But must prevent trouble before it happens.Through using finding, two kinds of brands of Mitsubishi, Fuji, because has fully considered various kinds of abominable running environment in design and manufacture.The dependability and service life under the same condition are higher than some brands.One small city of mountain area of west place in Hubei in Hubei, average 1200m above sea level, the humidity on the high side of long-term most of the time(about 80%), the sulfur dioxide is seriously polluted, a set of frequency conversion that one factory produces supplies water of the equipment, because has not considered above-mentioned factors, less than one year, the relevant parts of the equipment are corroded seriously.And the like product which we designed, installed in the same area, because has fully considered the situations of different difference, on the selecting types of the equipment and component, have adopted the ship standard.Through the use of more than two years, ran well, stood the tests of different sternness.Find in using actually, the frequency converter itself is that a strong interference takes place in the source, will often influence the normal running of the equipment.Especially when the low rotational speed of the water pump operates, the frequency shown on the frequency converter does not correspond to actual operation frequency.Generally there are two kinds of spread ways to interfere: The circuit bunch is disturbed and space radiation is interfered.Can take the corresponding measure to solve according to the actual conditions of the scene.For example is it strain wave and absorb the return circuit to increase to programmable power end of controller, PID regulator introduction of unit output sure to have reliable shielding, link frequency converter, ground terminal of electrical machinery with earth stake firmly, control the line and motive force line leave certain distance, in order to strengthen and resist the electromagnetic ability to interfere.Only in this way, can make system keep the long and steady working state in high temperature, humidity, mould, strong harsh terms of interfering etc.4、Conclusions

Are by way of adjusting the speed as the central water supply in frequency conversion, the result is obvious to economize on water, economize on electricity, can be extensively suitable for 20-10000 residents the biotope, skyscraper, hotels and restaurants, fire control or district pressurize and supply water, it is ideal facilities that the medium and small-scale waterworks supplied water too.Its amount of water quality supported is high, the economic benefits are obvious, the social benefit is enormous, with the development of national economy and constant improvement of the living standards of the people, it is sure to be used and popularized progressively in our country

5、List of references

Zhang Wanzhong, Zhu Jie, Wang Mingquan.A kind of new-type frequency conversion constant pressure supplies water of the plan of design of the pump station.Electrical age, 1999(10): 22-232 Liu YingChun.Principle design of the sensor and application.Beijing: University of Science and Technology of the national defense publishing Press, 1989.59-623

Lu Guangda.Electric installation project manual of the building.Beijing: The electric publishing house of water conservancy, write the group in 1995.222-2244“The automatic projecting ”.Give and drain off water the automatic project.Beijing: The electric publishing house of water conservancy, 1997.301-312

第五篇：耐克英文簡(jiǎn)介

NIKE英文介紹

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