變壓器畢業(yè)論文外文文獻翻譯

1、英文資料及其翻譯TransformerTypes and Construction of TransformerA transformer is a device that alternating current electric energy at one voltage level into alternating current electric energy at another voltage level through the actionof a magnetic field.It consists of two or more coils wire wrapped around

2、 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.One of the transformer windings is connected to a source of ac electric power,and the second(and perhaps third) transformer winding

3、supplies electric power to loads. the transformer winding connected to the power souce is calledthe primary winding 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 windin

4、g.Power 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 type of construction is know ascoreform .The other type consists of three-l

5、egged laminated core with the windings wrapped around the center leg .This type of construction is know as shell form.In eithercase,the core is constructed of thin laminations electrically isolated form each other in order in order to reduce eddy currents to a minimum.Power transformer are given a v

6、ariety of different names, depending on their use in power systems.A transformer connected to the output of a generator and used to stepits voltage up to transformer levels is sometimes called unit transformer. The transformer ai the other end of the transformer line,which steps the voltage down fro

7、mtransmission levels to distribution levels,is called a substation transformer.Finally,the transformer that takes the distribution voltage and steps is down to the final voltage ai which the power is actually used is called a distribution transformer.All these devices are essentially the same-the on

8、ly difference among them is their intended use.In addition to the various power transformer, two special-purpose transformers are used with electric machinery and power systems.The first of these special transformers is a device specially designed to sample a high voltage and produce a low secondary

9、 voltage directly proportional to it.Such a transformer is called a potential transformer.A power transformer also produces a secondary voltage directly proportional to its primary voltage;the difference between a potential transformer and a power transformer is that the potential transformer is des

10、igned to handle only a very small current.The second type of special transformer is a device designed to provide a secondary current.much smaller than but directly proportional to its primary current.This device is called a current transformer.Cirtcuit BreakersA circuitbreakerismechanicalswitchingde

11、vicecapableofmaking,andbreaking currents under normal circuit conditions andalsomaking.carringforaspecifiedtime,andmediujmin whichcircuitinterruption isperformedmaybedesignatedbyasuitableprefix, for example,air-blastcircuitbreaker,oil circuitbreaker.Thecircuitbreakerscurrently in usecanbedlassifiedi

12、ntothefollowingcategoriesaccordingtothearc-quenchingprinciples:airswetchesoelciryitbreakers,minmum-oilcircuit breakers,air-blastcircuitbreakers,themageneticaircircuitbreakers,minimum-oilcircuitbreakers,aer-blastcircuitbreakers,thebyvoltage,insulationlevelcurrent,interruptingcapabilities,transientrec

13、overycoltage,interrupting tiome,and trip delay.The nameplate on a circuit breaker usuallyindicates: ? .The maximumsteady-statecurrentit cancarry,2.Themaximuminterrupting current,3. The maximum line voltage,4.The interrupting time in cycles,The interrupting time in may last form 3 to 8 cycles on a 60

14、 Hz system. To interrubtlargecurrentsquickly,wehave to ensure rapid cooling. High-speedinterruptionlunits the damage transmission lines and equipment and, equally important,it helpsto mainmain the stability of the system whenever a contingency occurs. The mainpartsofacircuit breakerareusually:arc-qu

15、enchingchamber(orinterrupterwithmoving and fixed contacts) operating mechanism and supporting structures.Air Switches-With increasing currents and voltages, spring-action driving mechanisms were developed to reduce contact buring by faster-opening operation.Later,main contacts were fitted with arcin

16、g contacts of special material and shape,which opend after and closed before the main contacts.Further improvements of the air switch were the bursh-type contact with a wiping and cleaning function,the insulating barrier leading to arc chutes,and blowout coils with excellent arc-extinguishing proper

17、ties.These features,as well as the horn gap contact,are still in use in low voltage as and de breakers.Oil Circuit Breaker Around 1900, in 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 estab

18、lishing the open break after current zero.Deiongrids,oil-blast features,pressure-tight joints and vents,new operating mechanisims,and multiple interrupter were introucedover several decades to makethe oil circuit breaker a reliable apparatus for system voltage up to 362kV變壓器變壓器的類型和結(jié)構(gòu)變壓器是一個通過磁場作用將一個交

19、流電壓值變成另一個電壓值的設(shè)備。它 由兩條或更多的金屬絲纏繞在一個核心磁鐵上組成的。 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。一組變壓器繞組連接到一個交流電源上? 同時第二組 ? 或許第三組 ? 變壓器 繞組作為電源提供給負載。 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。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)造類型被認為是核心形式。 另一種類型是由繞組纏繞在中心引腳的疊片鐵心

20、構(gòu)成。這種構(gòu)造類型貝殼形式。其中任 意一種類型 ? 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。一個物理變壓器的一次繞組和二次繞組被纏繞成一個在內(nèi)部的另一個低壓繞組的上面。這樣安排達到了兩個目的? 1.它簡化了從磁芯到高壓繞組的絕緣問題。2.與過去將兩個繞組在磁心上隔離一定距離比起來? 它導(dǎo)致更少的漏通量。電力變壓器被賦予了很多不同的名字? 取決于它們在當前系統(tǒng)中的作用。一變壓器連接到一個發(fā)電機的輸出端 ? 并且用于步調(diào)它的電壓達到變壓器值有時被叫做單位變壓器。變壓器一個排在另一個后面 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

21、到最后的實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。斷路器空氣壓縮斷路器是一種機械開關(guān)設(shè)備? 能夠在正常和特殊情況下開斷電流? 比如說短路電流 ? 。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離通常被分為如下等級? 空氣開關(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、絕緣等級、電流開斷容量、 開斷時間的瞬時電壓恢復(fù)和條炸事件。斷路器的銘牌通常包括? 1. 最大可承受電流 ? 2.最 大中斷電流 ? 3.最大線路電

22、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 個周期 ? 為了快速中斷達負荷電流? 我們不得不確保它的持續(xù)冷卻、高 速開斷能限制對傳輸線路的損害 ? 這一點是同等重要的它幫助系統(tǒng)在任何事故發(fā)生時維持穩(wěn)定運行 ? 斷路器主要由操作機構(gòu)、執(zhí)行機構(gòu)和滅弧室組成。當有觸發(fā)電流或者電壓時? 空氣隔離開關(guān)的彈簧操作機構(gòu)迅速動作以用來減少觸點的燒損 ? 主觸點的特殊形狀和使用材料完全適合電弧的接觸 ? 空氣隔離開 關(guān)更進一步的改進是由于滅弧的性能、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)用于低電壓等級和直流斷路器中。多油斷路器出現(xiàn)于1900 前后

23、? 主要用來滿足新的開斷容量的要求? 交流開關(guān) 被浸入一個油缸之中? 油在熄滅電弧和在電流過零時建立開斷功能是十分有效滅弧柵、噴油嘴、新的操作機構(gòu)和多種新的斷路功能在近幾十年引進使用多油斷 路器能夠適應(yīng)362kV 。畢業(yè)論文答辯五大步驟流程畢業(yè)論文 答辯流程一般包括自我介紹、 答辯人陳述、提問與答辯、總結(jié)和致謝五部分， 下面是小編搜集整理的畢業(yè) 論文答辯五大步驟流程，供大家閱讀查看。范文：各位老師與同學(xué)：大家好 ! 我來自 XX學(xué)院 XX專業(yè)，我叫 XX,今天我演講題目是會計基本職業(yè)道德 - 不做假帳。金融業(yè)屬于高風(fēng)險行業(yè)，其行業(yè)效益需要通過會計報表和會計資料反映出來， 如果會計資料失真， 將

24、無法真實反映企業(yè)經(jīng)營狀況， 使管理者無法正確決策， 最終導(dǎo)致經(jīng)營風(fēng)險，嚴重干擾正常社會經(jīng)濟秩序，損害國家和社會公眾利益。本文以此為背景， 研究會計從業(yè)人員如何不做假賬， 提升個人職業(yè)道德，促進企業(yè)健康發(fā)展。 首先我們簡要介紹了當前會計職業(yè)道德發(fā)展現(xiàn)狀，其次探討會計工作中做假賬問題， 再次研究如何避免做假賬行為，提升會計人員職業(yè)素養(yǎng)。本文的創(chuàng)新點在于著眼做假賬行為， 深入研究做假賬的動機、 影響因素，從這一獨特視角分析會計職業(yè)道德建設(shè)問題， 為會計誠信研究提供一些參考意義， 但由于本人研究視角有限， 不能對會計舞弊行為一一分析，研究內(nèi)容局限，望各位老師指點，提供好的建議。以上就是我的論文答辯內(nèi)容，謝謝各位老師。論文答辯流程：自我介紹：自我介紹作為答辯的開場白，包括姓名、學(xué)號、專業(yè)。介紹時要舉止大方、態(tài)度從容、面帶微笑，禮貌得體的介紹自己，爭取給答辯小組一個良好的印象。好的開端就意味著成功了一半。答辯人陳述：收到成效的自我介紹只是這場答辯的開始，接下來的自我陳述才進入正軌。自述的主要內(nèi)容包括論文標題; 課題背景、選擇此課題的原因及課題現(xiàn)階段的發(fā)展情況; 有關(guān)課題的具體內(nèi)容，其中包括答辯人所持的觀點看法、研究過程、實驗數(shù)據(jù)、結(jié)果;