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1、<p><b>  附錄Ⅰ</b></p><p><b>  英文資料及其翻譯</b></p><p>  Transformer</p><p>  Types and Construction of Transformer</p><p>  A transformer is a d

2、evice that alternating current electric energy at one voltage level into alternating current electric energy at another voltage level through the action of a magnetic field.It consists of two or more coils wire wrapped

3、around a common ferromagnetic core.These coils are (usually)not directly connected. The only connection between the coils is the common magnectic flux presen within the core.</p><p>  One of the transformer

4、windings is connected to a source of ac electric power,and the second(and perhaps third) transformer winding supplies electric power to loads. the transformer winding connected to the power souce is called the primary wi

5、nding or input winding.and the winding connected to the loads is called the secondary winding or input winding.If there is a third winding on the transformer,it is called the tertiary winding.</p><p>  Powe

6、r transformer are constructed on one of two types of cores.one type of construction consists of a simple rectangular laminated piece of steel with the transformer windings wrapped around two sides of the rectangle.This t

7、ype of construction is know as coreform .The other type consists of three-legged laminated core with the windings wrapped around the center leg .This type of construction is know as shell form.In either case,the core is

8、constructed of thin laminations electrically isolated fo</p><p>  The primary and secondary windings in a physical transformer are wrapped one on top of the other with the low-voltage winding innermost.Such

9、an arrangement severs two purposes: 1.It simplifies the problem of insulating the high- voltage winding from the core.2.It results in much less leakage flux than would be the two windings were separated by a distance on

10、the core.</p><p>  Power transformer are given a variety of different names, depending on their use in power systems.A transformer connected to the output of a generator and used to step its voltage up to tr

11、ansformer levels is sometimes called unit transformer. The transformer ai the other end of the transformer line,which steps the voltage down from transmission levels to distribution levels,is called a substation transfor

12、mer.Finally,the transformer that takes the distribution voltage and steps is down to the fin</p><p>  In addition to the various power transformer, two special-purpose transformers are used with electric mac

13、hinery and power systems.The first of these special transformers is a device specially designed to sample a high voltage and produce a low secondary voltage directly proportional to it.Such a transformer is called a pote

14、ntial transformer.A power transformer also produces a secondary voltage directly proportional to its primary voltage;the difference between a potential transformer and a power</p><p>  Cirtcuit Breakers</

15、p><p>  A circuit breaker is mechanical switching device capable of making,and breaking currents under normal circuit conditions and also making.carring for a specified time ,and mediujm in which circuit interr

16、uption is performed may be designated by a suitable prefix, for example,air-blastcircuit breaker,oil circuit breaker.The circuit breakers currently in use can be dlassified into the following categories according to the

17、arc-quenching principles:air swetches oel ciryit breakers,minmum-oil circuit b</p><p>  Air Switches-With increasing currents and voltages, spring-action driving mechanisms were developed to reduce contact

18、buring by faster-opening operation.Later,main contacts were fitted with arcing contacts of special material and shape,which opend after and closed before the main contacts.Further improvements of the air switch were the

19、bursh-type contact with a wiping and cleaning function,the insulating barrier leading to arc chutes,and blowout coils with excellent arc-extinguishing properties</p><p>  Oil Circuit Breaker Around 1900, in

20、order to cope with the new requirement for “interrupting capacity”,AC switches were immersed in a tank of oil. Is very effective in quenching the arc and establishing the open break after current zero.Deion grids,oil-bla

21、st features,pressure-tight joints and vents,new operating mechanisims,and multiple interrupter were introucedover several decades to make the oil circuit breaker a reliable apparatus for system voltage up to 362kV</p&

22、gt;<p><b>  變壓器</b></p><p><b>  變壓器的類(lèi)型和結(jié)構(gòu)</b></p><p>  變壓器是一個(gè)通過(guò)磁場(chǎng)作用將一個(gè)交流電壓值變成另一個(gè)電壓值的設(shè)備。它由兩條或更多的金屬絲纏繞在一個(gè)核心磁鐵上組成的。這些繞線(一般)不直接接觸。繞線之間唯一的聯(lián)系是它們共有的存在于磁芯的磁通量。</p>

23、<p>  一組變壓器繞組連接到一個(gè)交流電源上,同時(shí)第二組(或許第三組)變壓器繞組作為電源提供給負(fù)載。連接到電源上的變壓器繞組叫做一次繞組,或者輸入繞組。連接負(fù)載的繞組叫做二次繞組或者輸出繞組。如果變壓器上有第三繞組,它叫做三次繞組。</p><p>  電力變壓器由一兩種磁芯中的一種構(gòu)成。一種構(gòu)造是由一種簡(jiǎn)單的變壓器繞組纏繞在矩形兩邊的矩形薄鋼片組成。這種構(gòu)造類(lèi)型被認(rèn)為是核心形式。另一種類(lèi)型是由繞組纏

24、繞在中心引腳的疊片鐵心構(gòu)成。這種構(gòu)造類(lèi)型貝殼形式。其中任意一種類(lèi)型,磁心都是由排列整齊的彼此之間電氣隔離的薄鐵片構(gòu)成,以便將渦流減小到最小值。</p><p>  一個(gè)物理變壓器的一次繞組和二次繞組被纏繞成一個(gè)在內(nèi)部的另一個(gè)低壓繞組的上面。這樣安排達(dá)到了兩個(gè)目的:1.它簡(jiǎn)化了從磁芯到高壓繞組的絕緣問(wèn)題。2.與過(guò)去將兩個(gè)繞組在磁心上隔離一定距離比起來(lái),它導(dǎo)致更少的漏通量。</p><p> 

25、 電力變壓器被賦予了很多不同的名字,取決于它們?cè)诋?dāng)前系統(tǒng)中的作用。一變壓器連接到一個(gè)發(fā)電機(jī)的輸出端,并且用于步調(diào)它的電壓達(dá)到變壓器值有時(shí)被叫做單位變壓器。變壓器一個(gè)排在另一個(gè)后面——將電壓從傳送值步降到分布值,被叫做變電站。最后,變壓器將分布電壓和步幅降到最后的實(shí)際使用的電能被叫做發(fā)送變壓器。所有這些設(shè)備本質(zhì)上都是相同的——它們之間唯一不同的是它們的特定用途。</p><p><b>  斷路器<

26、/b></p><p>  空氣壓縮斷路器是一種機(jī)械開(kāi)關(guān)設(shè)備,能夠在正常和特殊情況下開(kāi)斷電流(比如說(shuō)短路電流)。例如空氣斷路器、油斷路器,干擾電路的導(dǎo)體因該安全可靠的應(yīng)用于其中,電流斷路器按滅弧遠(yuǎn)離通常被分為如下等級(jí):空氣開(kāi)關(guān)斷路器、油斷路器、少油斷路器、壓縮空氣斷路器、具有消磁性質(zhì)的隔離開(kāi)關(guān)、六氟化硫斷路器和真空斷路器。他們的參數(shù)有電壓等級(jí)、絕緣等級(jí)、電流開(kāi)斷容量、開(kāi)斷時(shí)間的瞬時(shí)電壓恢復(fù)和條炸事件。斷路器

27、的銘牌通常包括:1.最大可承受電流;2.最大中斷電流;3.最大線路電壓;4.中斷周期數(shù)量。在60HZ的系統(tǒng)中,中斷可能持續(xù)3至8個(gè)周期,為了快速中斷達(dá)負(fù)荷電流,我們不得不確保它的持續(xù)冷卻,、高速開(kāi)斷能限制對(duì)傳輸線路的損害,這一點(diǎn)是同等重要的它幫助系統(tǒng)在任何事故發(fā)生時(shí)維持穩(wěn)定運(yùn)行,斷路器主要由操作機(jī)構(gòu)、執(zhí)行機(jī)構(gòu)和滅弧室組成。</p><p>  當(dāng)有觸發(fā)電流或者電壓時(shí),空氣隔離開(kāi)關(guān)的彈簧操作機(jī)構(gòu)迅速動(dòng)作以用來(lái)減少觸

28、點(diǎn)的燒損,主觸點(diǎn)的特殊形狀和使用材料完全適合電弧的接觸,空氣隔離開(kāi)關(guān)更進(jìn)一步的改進(jìn)是由于滅弧的性能、絕緣隔板組成的滅弧罩、帶滅弧功能的觸頭等這些特殊性質(zhì),所以仍被應(yīng)用于低電壓等級(jí)和直流斷路器中。</p><p>  多油斷路器出現(xiàn)于1900前后,主要用來(lái)滿足新的開(kāi)斷容量的要求,交流開(kāi)關(guān)被浸入一個(gè)油缸之中,油在熄滅電弧和在電流過(guò)零時(shí)建立開(kāi)斷功能是十分有效,滅弧柵、噴油嘴、新的操作機(jī)構(gòu)和多種新的斷路功能在近幾十年引進(jìn)

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