變頻技術(shù)中英文翻譯資料

1、變頻技術(shù)1.1 變頻技術(shù)的普及前景電機(jī)交流變頻調(diào)速技術(shù)是當(dāng)今節(jié)電、改善工藝流程以提高產(chǎn)品質(zhì)量和改善環(huán)境、推動(dòng)技術(shù)進(jìn)步的一種主要手段。變頻調(diào)速以其優(yōu)異的調(diào)速和起制動(dòng)性能，高效率、高功率因數(shù)和節(jié)電效果，廣泛的適用范圍及其它許多優(yōu)點(diǎn)而被國內(nèi)外公認(rèn)為最有發(fā)展前途的調(diào)速方式。電氣傳動(dòng)控制系統(tǒng)通常由電動(dòng)機(jī)、控制裝置和信息裝置3部分組成，電氣傳動(dòng)關(guān)系到合理地使用電動(dòng)機(jī)以節(jié)約電能和控制機(jī)械的運(yùn)轉(zhuǎn)狀態(tài)，實(shí)現(xiàn)電能-機(jī)械能的轉(zhuǎn)換，達(dá)到優(yōu)質(zhì)、高產(chǎn)、低耗目的。電氣傳動(dòng)分成不調(diào)速和調(diào)速兩大類，調(diào)速又分交流調(diào)速和直流調(diào)速兩種方式。不調(diào)速電動(dòng)機(jī)直接由電網(wǎng)供電，但隨著電力電子技術(shù)的發(fā)展這類原本不調(diào)速的機(jī)械越來越多地改用調(diào)速傳動(dòng)

2、以節(jié)約電能(節(jié)約15%20%或更多)，改善產(chǎn)品質(zhì)量，提高產(chǎn)量。在我國60%的發(fā)電量是通過電動(dòng)機(jī)消耗的，因此調(diào)速傳動(dòng)是一個(gè)重要行業(yè)，已經(jīng)得到國家重視，目前已有一定規(guī)模。近年來交流調(diào)速中最活躍、發(fā)展最快的就是變頻調(diào)速技術(shù)，變頻調(diào)速是交流調(diào)速的基礎(chǔ)和主干內(nèi)容。上個(gè)世紀(jì)變壓器的出現(xiàn)使改變電壓變得很容易，從而造就了一個(gè)龐大的電力行業(yè)。長期以來，交流電的頻率一直是固定的，變頻調(diào)速技術(shù)的出現(xiàn)使頻率變?yōu)榭梢猿浞掷玫馁Y源。這10年來，變頻技術(shù)的應(yīng)用在我國有很大的發(fā)展，并取得了良好的效果可以說，變頻技術(shù)已為大多數(shù)用戶所接受，但是不能不指出，我國在變頻技術(shù)的應(yīng)用方面，與發(fā)達(dá)國家的水平尚有很大差距，目前，我國在用的

3、交流電動(dòng)機(jī)使用變頻調(diào)速運(yùn)行的僅6%左右，而下業(yè)發(fā)達(dá)國家已達(dá)(60%70%)，日本在風(fēng)機(jī)、水泵上變頻調(diào)速的采用率已達(dá)10% ,而我國還不足0.01%.在日本，空調(diào)器的70%采用了變頻調(diào)速，而我國才剛剛起步。從這個(gè)現(xiàn)實(shí)出發(fā)，變頻技術(shù)尚有很大的發(fā)展空間，應(yīng)該鍥而不舍地做好推廣應(yīng)用工作。而且隨著控制技術(shù)和控制手段的不斷提高，變頻調(diào)速又由變壓變頻控制的變頻調(diào)速發(fā)展到了矢量控制變頻調(diào)速，通過控制交流電動(dòng)機(jī)里相當(dāng)于并勵(lì)直流電動(dòng)機(jī)勵(lì)磁繞組的磁通變化，提高變頻器的恒轉(zhuǎn)矩輸出范圍和動(dòng)靜態(tài)特性，使得交流電動(dòng)機(jī)變頻調(diào)速系統(tǒng)的性能超過了直流電動(dòng)機(jī)調(diào)壓調(diào)速系統(tǒng)的性能。為了簡(jiǎn)化控制系統(tǒng)，減少設(shè)備故障率，在矢量控制變頻調(diào)速的

4、基礎(chǔ)上又發(fā)展了無速度傳感器的矢量控制變頻調(diào)速。在一些對(duì)動(dòng)靜態(tài)特性要求不太高的應(yīng)用中，無速度傳感器的矢量控制變頻調(diào)速己完全可以和有速度傳感器的矢量控制變頻調(diào)速相媲美。矢量控制對(duì)交流電機(jī)調(diào)速具有劃時(shí)代的意義。變頻調(diào)速是電機(jī)調(diào)速的最佳方式，是企業(yè)技術(shù)改造和產(chǎn)品更新?lián)Q代的理想設(shè)備，是工業(yè)自動(dòng)化系統(tǒng)必不可少的組成部分，是實(shí)現(xiàn)生產(chǎn)過程和管理自動(dòng)化的前提，也是信息化發(fā)展的先決條件。在我國傳統(tǒng)產(chǎn)業(yè)中，采用直流電機(jī)拖動(dòng)的調(diào)速系統(tǒng)約占調(diào)速系統(tǒng)總量的85%90%，而交流調(diào)速系統(tǒng)僅占10%15%。效率低、質(zhì)量差、消耗大、故障率高己成為制約企業(yè)發(fā)展的瓶頸。因此，必須積極推廣先進(jìn)的交流變頻調(diào)速技術(shù)，用先進(jìn)的設(shè)備武裝傳統(tǒng)產(chǎn)

5、業(yè)，促進(jìn)自動(dòng)化、工業(yè)化和信息化的進(jìn)一步發(fā)展。1.2 變頻調(diào)速發(fā)展趨勢(shì)如果說以第一個(gè)晶閘管的出現(xiàn)作為交流電動(dòng)機(jī)變頻調(diào)速的起點(diǎn)，可以認(rèn)為它的發(fā)展歷史己40多年了。而變頻調(diào)速技術(shù)真正高速發(fā)展時(shí)期，應(yīng)該是在PWM調(diào)制技術(shù)的出現(xiàn)和微機(jī)控制技術(shù)發(fā)展之后。特別是最近20年來，隨著交流調(diào)速技術(shù)的應(yīng)用普及，交流變頻調(diào)速在化工、火電廠、礦山、油田、機(jī)械制造、城市建設(shè)、水處理、甚至家電等行業(yè)己經(jīng)全面推廣使用，一般主要用于節(jié)能及控制。隨著變頻技術(shù)的普及和深入，以及國際、國內(nèi)電器設(shè)備使用的有關(guān)標(biāo)準(zhǔn)意識(shí)的強(qiáng)化，電力系統(tǒng)行業(yè)和用戶對(duì)變頻技術(shù)的質(zhì)量要求也越來越高。變頻調(diào)速的發(fā)展趨勢(shì)主要圍繞下面幾個(gè)方而展開。1) 高性能的智能

6、控制變頻器380V系統(tǒng)的低壓變頻器是國內(nèi)的主要研究對(duì)象，應(yīng)用交流調(diào)速的基本理論，結(jié)合神經(jīng)網(wǎng)絡(luò)控制、魯棒控制、模糊控制，或其他智能控制等手段，實(shí)現(xiàn)電機(jī)運(yùn)行參數(shù)的自動(dòng)辨識(shí)，以期達(dá)到自適應(yīng)、自調(diào)整的最優(yōu)控制。這方面己有一定的研究成果。2) 速度傳感器研究從前面所述的各種變頻調(diào)速的理論可知，一般系統(tǒng)都要用到轉(zhuǎn)速傳感器。在實(shí)際使用中，由于變頻設(shè)備和被控電動(dòng)機(jī)有一定的距離，而高精度的轉(zhuǎn)速傳感器都要使用專門的電源，被控電動(dòng)機(jī)有的是在戶外，運(yùn)行工況非常惡劣，要保證速度反饋的準(zhǔn)確性，有時(shí)不得不采取特別措施，因此也會(huì)增加額外費(fèi)用，運(yùn)行的可靠性和控制精度也會(huì)因此受到影響。無速度傳感器的變頻調(diào)速系統(tǒng)，是通過現(xiàn)場(chǎng)采集的

7、電流電壓量，以及控制的實(shí)施策略，綜合出被控電機(jī)的實(shí)際轉(zhuǎn)速。這種控制方案要求計(jì)算機(jī)的控制速度較高，并有足夠的精度。3) 針對(duì)功率因數(shù)提高和諧波污染的研究低壓變頻調(diào)速系統(tǒng)的控制雖然己經(jīng)是非常成熟了，但目前國際、國內(nèi)的產(chǎn)品，一般都是矢量控制和直接轉(zhuǎn)矩控制，重點(diǎn)放在電機(jī)變頻控制理論的實(shí)現(xiàn)和完善上，而對(duì)變頻器的輸出波形、功率因數(shù)，以及諧波污染等問題還沒有引起足夠的重視。最近10多年來，國外在這一領(lǐng)域己有較深入的研究。有的針對(duì)功率因數(shù)，有的強(qiáng)調(diào)輸出波形。多重化技術(shù)就是為了解決輸出波形問題。最近幾年的研究表明，利用PWM輸出控制解決諧波輸出問題，是比較理想的方法，它可以省去多重化中的變壓器，或過多的開關(guān)元器

8、件，使變頻器的體積和重量減少，但這種方法不能解決所有諧波的消除問題，只能部分消除特定諧波。這方面的研究論文還不多，也還沒有成熟的類似低壓變頻器的產(chǎn)品出現(xiàn)。4) 高壓變頻器的研究變頻器的主要作用之一是節(jié)能。而高壓電動(dòng)機(jī)的節(jié)能效果是比較明顯的，大功率的風(fēng)機(jī)和水泵用電動(dòng)機(jī)一般都是高壓電動(dòng)機(jī)。國內(nèi)，高壓變頻調(diào)速和它的節(jié)能控制還是一個(gè)比較薄弱的環(huán)節(jié).它主要是針對(duì)610kV的交流電動(dòng)機(jī)進(jìn)行變頻調(diào)速控制。這種高壓電動(dòng)機(jī)廣泛應(yīng)用于火力發(fā)電廠的送風(fēng)機(jī)和引風(fēng)機(jī)上。同樣也可用于其他如石油化工、礦山、冶煉、機(jī)械制造等行業(yè)的變頻節(jié)能控制。從某種意義上講，由于目前國內(nèi)還不能完全生產(chǎn)高質(zhì)量的合格電力電子器件，而且，國外低壓

9、變頻器的性能價(jià)格比也比國內(nèi)自己研究的變頻器高得多。因此,在這方面還有許多研究工作要做。隨著電力電子技術(shù)最近20多年的飛速發(fā)展，功率半導(dǎo)體器件的成本逐年下降，技術(shù)工藝和性能也得到不斷改善.電力電子器件的應(yīng)用己從傳統(tǒng)的直流調(diào)速、直流屏、斬波器等領(lǐng)域延伸到交流調(diào)速和電力系統(tǒng)的質(zhì)量控制領(lǐng)域.并正朝著高電壓、大功率的方向發(fā)展.這也是千年之交和世紀(jì)之交我國電力電子技術(shù)應(yīng)用的發(fā)展趨勢(shì)。5) 無換向器同步電機(jī)的變頻調(diào)速無換向器電動(dòng)機(jī)也是在20世紀(jì)70年代發(fā)展起來的新型調(diào)速系統(tǒng)。它是一種變頻調(diào)速同步電動(dòng)機(jī).也可以認(rèn)為是一種用半導(dǎo)體電子開關(guān)線路代替換向器和電刷作用的直流電動(dòng)機(jī)。根據(jù)采用的控制方式不同.可分為直流無

10、換向器電動(dòng)機(jī)和交流無換向器電動(dòng)機(jī)。直流無換向器電動(dòng)機(jī)采用交-直-交或直-交變頻控制系統(tǒng);交流無換向器電動(dòng)機(jī)采用交-交變頻控制系統(tǒng)。近10年來.國內(nèi)外雜志上有許多相關(guān)的研究論文。而且，也有一定的成果出現(xiàn)。1.3 變頻調(diào)速控制方式交流變頻調(diào)速技術(shù)在20世紀(jì)得到了迅速發(fā)展。這與一些關(guān)鍵性技術(shù)的突破性進(jìn)展有關(guān)，它們是交流電動(dòng)機(jī)的矢量控制技術(shù)、直接轉(zhuǎn)矩控制技術(shù)、PWM技術(shù)以及微型計(jì)算機(jī)和大規(guī)模集成電路為基礎(chǔ)的全數(shù)字化控制技術(shù)、自整定技術(shù)等。1) 矢量控制技術(shù)矢量變換控制技術(shù)是西門子公司于1971年提出的一種新的控制思想和控制理論。它是以轉(zhuǎn)子磁場(chǎng)定向，采用矢量變換的方法實(shí)現(xiàn)定子電流勵(lì)磁分量和轉(zhuǎn)矩分量之間的

11、解藕，達(dá)到對(duì)交流電動(dòng)機(jī)的磁鏈和電流分別控制的目的，從而獲得了優(yōu)良的靜、動(dòng)態(tài)性能。迄今為止，矢量控制技術(shù)己經(jīng)獲得了長足的發(fā)展，并得到了廣泛應(yīng)用。2) 無速度傳感器矢量控制技術(shù)無速度傳感器控制技術(shù)免去了傳感器帶來的環(huán)境適應(yīng)性、安裝維護(hù)等問題，降低了成本，提高了系統(tǒng)的可靠性，同時(shí)結(jié)合矢量控制，具有矢量控制的優(yōu)良性能。無速度傳感器技術(shù)中速度估算的方法，除了根據(jù)數(shù)學(xué)模型計(jì)算電動(dòng)機(jī)轉(zhuǎn)速外，目前應(yīng)用較多的有模型參考自適應(yīng)法和擴(kuò)展卡爾曼濾波法。此外全維轉(zhuǎn)子磁通觀測(cè)器，齒諧波電勢(shì)(RSH)等理論也出現(xiàn)在無速度傳感器技術(shù)中。從1983年提出無速度傳感器矢量控制策略以來，一直受到學(xué)術(shù)界和產(chǎn)業(yè)界的高度重視，日立、安川

12、電機(jī)等公司在1987年分別發(fā)表了研究成果，并相繼推出了產(chǎn)品。目前，無速度傳感器矢量控制變頻器的調(diào)速范圍為1:50左右，個(gè)別廠商有1:75甚至更高的產(chǎn)品。3) 直接轉(zhuǎn)矩控制技術(shù)1985年.德國的M . Depen-block首次提出直接轉(zhuǎn)矩控制技術(shù)(DTC)。DTC控制直接在定子坐標(biāo)系下分析交流電動(dòng)機(jī)的數(shù)學(xué)模型。采用定子磁場(chǎng)定向而無需解藕電流，直接控制電動(dòng)機(jī)的磁鏈和轉(zhuǎn)矩，以使轉(zhuǎn)矩得到快速響應(yīng)，從而獲得高效的控制性能。直接轉(zhuǎn)矩控制技術(shù)是近10年繼矢量控制技術(shù)之后發(fā)展起來的又一種新型的高性能交流變頻調(diào)速技術(shù)，這種控制技術(shù)與矢量控制技術(shù)相比，對(duì)電機(jī)參數(shù)不敏感，不受轉(zhuǎn)子參數(shù)的影響，簡(jiǎn)單易行，具有廣闊的發(fā)

13、展和應(yīng)用前景。4) PWM控制技術(shù)1964年，德國的A. Schonung等率先提出了脈寬調(diào)制(PWM -pulse width modulation)變頻的思想，為近代交流調(diào)速系統(tǒng)開辟了新的發(fā)展領(lǐng)域。PWM控制技術(shù)通過改變矩形脈沖的寬度來控制逆變器輸出交流基波電壓的幅值，通過改變調(diào)制周期來控制其輸出頻率，從而在逆變器上同時(shí)進(jìn)行輸出電壓幅值和頻率的控制。PWM技術(shù)簡(jiǎn)化了逆變器的結(jié)構(gòu)，能夠明顯的改善變頻器的輸出波形，降低電動(dòng)機(jī)的諧波損耗，并減小轉(zhuǎn)矩脈動(dòng)，同時(shí)提高了系統(tǒng)的動(dòng)態(tài)響應(yīng)性能。PWM技術(shù)還可用于整流器的控制，能夠?qū)崿F(xiàn)輸入電流非常接近正弦.。并可使電網(wǎng)功率因數(shù)為1。PWM整流器因而被稱為“綠

14、色”變流器。目前，PWM技術(shù)己成為變頻器中應(yīng)用最為廣泛的控制技術(shù)。交流電機(jī)調(diào)速性能的不斷提高在很大程度上是由于PWM技術(shù)的不斷進(jìn)步。目前廣泛應(yīng)用的是在規(guī)則采樣PWM的基礎(chǔ)上發(fā)展起來的準(zhǔn)優(yōu)化PWM法，即三次諧波疊加法和電壓空間矢量PWM法。5) 數(shù)字化控制技術(shù)控制技術(shù)的數(shù)字化是靜止變頻裝置的核心技術(shù)，也是今后的發(fā)展趨勢(shì)。目前市場(chǎng)上的變頻裝置幾乎全面實(shí)現(xiàn)了數(shù)字化控制。采用DSP和ASIC技術(shù)實(shí)現(xiàn)了快速運(yùn)算和高精度控制，可以得到良好的電流波形，使變頻器的噪音大幅度降低，并且掃描時(shí)間大幅度縮短，目前電流響應(yīng)為0.10.7ms，速度響應(yīng)為24 ms,足以滿足傳動(dòng)領(lǐng)域的控制要求。同時(shí)由于應(yīng)用微電子技術(shù)和A

15、SIC技術(shù)，裝置的元器件數(shù)量得以大幅度減少，從而使變頻裝置的體積減小，可靠性得到大幅度提高。全數(shù)字控制方式使變頻器的信息處理能力大為增強(qiáng)。采用模擬控制方式無法實(shí)現(xiàn)的復(fù)雜控制在今天都己成為現(xiàn)實(shí)，從而所謂的RAS概念即可靠性(Reliability)、可操作性(Availability)、可維修性(Serviceability)得以充實(shí)。6) 自整定技術(shù)自整定技術(shù)在變頻調(diào)速系統(tǒng)中的應(yīng)用日益廣泛，它可以根據(jù)速度和負(fù)載的變化自動(dòng)調(diào)整控制系統(tǒng)的參數(shù)，使得系統(tǒng)具有快速的動(dòng)態(tài)響應(yīng)。自整定技術(shù)分為離線式和在線式兩種。離線式的研究成果己經(jīng)在相當(dāng)多的產(chǎn)品中應(yīng)用，它是在運(yùn)行系統(tǒng)程序之前通過運(yùn)行一段自整定程序，辨識(shí)相

16、關(guān)數(shù)據(jù)，并修改系統(tǒng)程序的相關(guān)參數(shù)，以期獲得良好的系統(tǒng)控制性能。另外，改進(jìn)控制技術(shù)，提高系統(tǒng)魯棒性也和自整定技術(shù)緊密相聯(lián)系。外文文獻(xiàn)1 Frequency Variation Speed Control1.1 The Popularity and Prospect of Frequency Variation Speed ControlThe electrical machinery exchange frequency conversion velocity modulation technology is the electricity saving, the improvement tec

17、hnical process improves the product quality and the improvement environment, the impetus technology advancement one main method now The frequency conversion velocity modulation by its outstanding velocity modulation and the braking quality, the high efficiency, the high power factor and the electric

18、ity saving effect, the widespread applicable scope and other many merits by the domestic grandfather was thought most has the development future velocity modulation way. The electrical transmission control system usually by the electric motor, the control device and the information installs 3 parts

19、to be composed, the electrical transmission relates uses the electric motor by to save the electrical energy and to control the machinery reasonably the operating condition, the realization electrical energy - mechanical energy transformation, achieves, the high production, the low consumption goal

20、high quality. The electrical transmission divides into does not modulate velocity and modulates velocity two big kinds, the velocity modulation is divided the exchange to modulate velocity and to direct current modulates velocity two ways. The variable speed motor directly does not supply power by t

21、he electrical network But the machinery which does not modulate velocity along with electric power electronic technology development this kind of original manuscript more and more many changes to the velocity modulation transmission by to save the electrical energy The improvement product quality, e

22、nhances the output Therefore the velocity modulation transmission is an important profession, already obtained the country to take, at present had certain scale.In recent years exchanged in the velocity modulation most to be active, to develop quickest is the frequency conversion velocity modulation

23、 technology, the frequency conversion velocity modulation is exchanges the velocity modulation foundation and the branch content. The last century transformer appearance causes the change voltage to become very much easy, thus has accomplished a huge electric power profession. Since long ago, the al

24、ternating current frequency always is fixed, the frequency conversion velocity modulation technology appearance causes the frequency to become may the full use resources.In this recent 10 years, the frequency conversion technology application has the very big development in our country, and obtained

25、 the good effect to be possible to say, the frequency conversion technology has accepted for the majority users, but had no alternative but to point out, our country in frequency conversion technology application aspect, with developed country level Shang You very big disparity. At present, the AC m

26、otors we are using now use frequency variation speed control only about 6%, but the developed country is 60%70%, Japan on air blower, water pump frequency conversion velocity modulation use rate is 10%, but our country is less than 0.01%, In Japan air-conditioner using frequency variation technique

27、rate is 70%, but our countrys only then just started Embarks from this reality, frequency conversion technology remain have the very big development space, we should complete the promoted application work doggedly.And with the constant development of control technique and control avenue, frequency v

28、ariation speed controlled has developed the vector controlled frequency variation velocity modulation, by controlling the AC motor inside act for shunt DC motor field copers flux, to enhance the permanent torque output scope and static and dynamic character, make the AC motor frequency variation spe

29、ed controlled system superior to DC motor voltage variation speed controlled system. For simplifying the control system, reducing the fault rate, there has developed a vector controlled frequency variation speed control without speed sensor which based on the vector controlled frequency variation sp

30、eed control. In some application which have low require , vector controlled frequency variation speed control without speed sensor could completely compare with the vector controlled frequency variation speed control that have speed sensor. The vector control has the epoch-making significance to the

31、 AC current motor velocity modulation.Frequency variation speed control is the best way in the motor speed modulation, it is the perfect gear in the companys technical reform and product renewal, it is the essential composition in the industrial automatic system, it is the assumption of realizing th

32、e automatic of product proceed and management, it is also the precondition in the development of informationization. In our countrys traditional estate, using the DC motor speed control actuation account about 85%90% in the speed controlled system, but the AC speed controlled system account about 10

33、%15%. Low efficiency, bad quality, large cost, high fault rate have already been the bottleneck that restrain the development of the company. So, we must promote the advanced AC frequency variation speed control technique positively, arms the traditional industry with the advanced equipment, promote

34、 a further development in the automation, the industrialization and the informationization.1.2 Our Countrys Development Condition in Speed Controlled TechniqueOur country is a developing country, so many products research ability has behind the developed countries. From now on, the product of freque

35、ncy variation speed controlled that ourselves made only act for last century 90s in the international. With the reform and opening, rapid development of economic, forms a large market, it opens to the country companies, also the foreign companies. Many products are exported from the developed countr

36、ies, and runs well in our country, satisfied our need in fabrication and living. Many co-partership companies in our country make the international advanced products. The domestic complete department independently is designing the manufacture in the complete set installment to use the foreign import

37、 company and the joint venture supposes advanced each, own develop the application software, can provide the first-class electrical transmission control system for the domestic and foreign important engineering project. Although obtains very many result, but should see because domestic develops, the

38、 production product ability voluntarily is weak, is serious to the overseas companys dependence.As early as in the country 85 technical attack plan, the alternating velocity modulation technique was listed as the key technical attack project, but because our countrys electric power and electronic de

39、vice aggregate level is very low, although the production of IGBT、GTO component has introduced the overseas technique, it has not formed the economies of scale benefit, almost does not have the independent development ability of new frequency converter production, this has affected the domestic freq

40、uency conversion velocity modulation technique development in the certain degree. In the high efficiency AC-AC frequency convert technique、the motors without commutator technique and so on, the domestic product also has the suitable disparity in the digitization and the system reliable aspect compar

41、es with the overseas level, in the medium efficiency frequency convert technique, nearly all productions use ordinary V/F control inland, few adopt the vector control technique, and can not satisfied the market requirement in the variety and quality. But in overseas, the frequency conversion techniq

42、ue obtains the full development, and has obtained the remarkable achievement in each aspect. In power component aspect, high voltage、the appearance of SCR、GTO、IGBT、IGCT with high current capacity and the using in series and parallel, the high-pressured and high efficiency frequency converter product

43、ion obtains the production and the promoted application. In microelectronic technique aspect, 16bit and 32bit high speed microprocessors as well as the fast development of DSP and ASIC technique, provided the hardware method in realizing the frequency converter which with high accuracy multi-purpose

44、. In theory aspect, the vector control, the magnetic flux control, the torque control, the intelligent control, the new control theory and so on have provided the related rationale for the high performance frequency converter development, we may see that, in the overall, the alternating frequency co

45、nversion velocity modulation technique in our country has big disparity compares with international level.Therefore, the AC frequency variation speed control technique has the following sides:1) The basic research of control strategy in frequency converter has a large gap compares with the foreign l

46、evel.2) The technical level of the whole machine is low in the frequency converter, although we had input certainly people, material resources, but because of the disperse power, did not form a certainly technique and production scale.3) All the semiconductor power device product in the frequency co

47、nverter is blank.4) Correlative Industries and relative Industries drop behind.5) Few production and sale, low reliable and technological standards.With the development and improvement in the power electronic technique, power divert based on power electronic circuit technique and various control tec

48、hnique, the AC frequency variation speed controlled technique is mature day by day, and sure to be the main way in the future. With the constant development of power electronic technique, reliable character, well adoption, cheap price that the frequency converter have will become true. This techniqu

49、e will gain widely, popularity application .At present, foreign developed countries frequency convert technique towards to the miniaturization, high reliability, defend with harm, more function, high character, and our country is coming on now.1.3 Frequency Variation Speed Controlled ModeThe alterna

50、ting frequency conversion velocity modulation technique obtained the rapid development in 20th century. This is related with some crucial technical which gain unprecedented progress, they are Motor vector control technique, Direct torque control technique, PWM technique, Entire numerical control tec

51、hnique and self-setting technique which based on microcomputer and large scale integrated circuit, and so on.1) Vector Control TechniqueVector transformation control technique is a one kind of new control thought and control theory which posed by SIEMENS CO. in 1971. It is realizing the stator curre

52、nt excitation component and the torque component solution lotus root by rotor magnetic field direction detection, and vector transformation, achieved the goal that separately control the motor flux linkage and the electric current, as a result, obtain finely static, dynamic performance. Until now, t

53、he vector control technique has obtained the considerable development, and also obtained the widespread application.2) Vector Control Without Velocity Generator TechniqueVector control without velocity generator technique abolish the problems that the environment compatibility、install and maintenanc

54、e bring on, reduce the cost, enhance the system reliability, at the same time, union vector control, has the fine performance of vector control. The speed estimate method in vector control technique without velocity generator, besides basis mathematical model computation electric motor rotational sp

55、eed, at present the more applied are the model to refer auto-adapted method and expands the Kalman filtering law. In addition, entire Uygur rotor magnetic flux sight, tooth overtone electric potential, such as this theory and so on, also appearance in the vector control without velocity generator te

56、chnique. Since 1983 proposed the vector control without velocity generator technique control strategy, receives the academic circles and the industrial field continuously highly focused all the time. Hitachi company and Sichuan electrical machinery and so on had published the research results separa

57、tely in 1987, and had promoted the product one after another. At present, vector control without velocity generator technique in frequency converter controlling in the velocity modulation scope is about 1:50, some individual merchant has 1:75 or even higher product.3) Direct Torque Control Technique

58、In1985, Germanys M. Depen-block proposes the direct torque control technique（DTC） for the first time，The direct torque control technique analyzes the motor mathematical model directly under the stator coordinate system. Uses the stator magnetic field direction detection but not to need the solution

59、lotus root electric current，directly control the electric motor flux linkage and torque, enable the torque to obtain the fast response, in order to obtain the highly effective control performance.Direct torque control technique is another kind of new、high performance alternating frequency conversion velocity modulation technique after vector control technique in the nearly 10 years, this kind of control technique is insensitive to the electrical