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1、Chapter 3Power Electronic Technology,Section 1 Semiconductor Switches,semiconductor n. 半導(dǎo)體power electronicn. 電力電子lossn. 損耗,損失windingn. ①繞組,線圈 ②一圈,一轉(zhuǎn) transformer n 變壓器,變換器,變量器dielectric n. 介質(zhì),電介

2、質(zhì),絕緣材料;a. 絕緣的,介電的,介質(zhì)的,不導(dǎo)電的,,,,Words,eddyn. 渦流,旋渦; a. 渦流的,渦旋的;v. 渦流,起旋渦hysteresis n. 磁滯,滯后,遲滯on-state a. 通態(tài)的,接通的,開態(tài)off-state a. 關(guān)態(tài)的,斷開的,斷態(tài)的microamp n. 微安milliamp n. 毫安,,,,Words,waveform n. 波形zero-voltage

3、 電壓過零的zero-current 電流過零的,,,,Words,[1]The switching losses are significant and can be managed. They can be further divided into three components: (a) the on-state losses, (b) the off-state losses and ③the losses in

4、 the transition states.,開關(guān)損耗是很大的,但可以控制。開關(guān)損耗進一步可以分解成三個部分:接通狀態(tài)、關(guān)斷狀態(tài)和變換狀態(tài)的損耗。,Notes,[2]The practical switching devices have limited capabilities of rate of voltage transition and the rate of current steering. These nonabrup

5、t transition ratesgive rise to power losses in the switching devices. We will examine these switching losses in two cases separately: the inductive and capacitive loads.,實際開關(guān)裝置限制了電壓變換速率和電流換向速率。非突變引起了開關(guān)裝置的功率損失。我們將分別從感性負(fù)載和

6、容性負(fù)載兩種情況來分析開關(guān)損耗。,Notes,[3]The switching power losses increase linearly with the switching frequency like in the resistive case but about six times more. The upper bound on the switching frequency is also about half.,類似于電

7、阻負(fù)載的情況,開關(guān)功率損耗隨著開關(guān)頻率線性增大,但大約為電阻負(fù)載情況的6倍多。開關(guān)頻率的上限也約為一半。,Notes,[4]The capacitor is assumed to be large so that the voltage through it in steady state is nearly constant Uo. Assume that initially the switch is on, hence, the

8、current through the switch is IS. The capacitor voltage is Uo, the voltage across the switch is zero and the diode V1 is reverse biased. .,假設(shè)電容器很大,致使在穩(wěn)態(tài)狀態(tài)下其兩端的電壓接近為常數(shù)Uo。假使開關(guān)開始處于閉合狀態(tài),則通過開關(guān)的電流為IS。電容器的電壓為Uo,開關(guān)兩端的電壓為零,二極管V1反

9、向偏置。,Notes,Exercises,,,,,課內(nèi)完成section 1中的Exercises I, II and III,電力電子器件Power Electronic Device,‘‘Power Electronics Technology’’ 《電力電子技術(shù)》‘‘ Analog Electronic Techniques ’’ 《模擬電子技術(shù)》,Semiconductors半控型器件:Thyristor 晶閘管(SC

10、R: Silicon Controlled Rectifier),全控型器件:GTR 晶體管 (Giant Transistor)IGBT 絕緣柵雙極晶體管(Insulated-Gate Bipolar Transistor)Power MOSFET 電力場效應(yīng)晶體管(Metal Oxide Semiconductor Field Effect Transistor)GTO 門極可關(guān)斷晶閘管 (Gate-Turn

11、-Off Thyristor)不可控器件:Power Diode (Semiconductor Rectifier),電力電子器件Power Electronic Device,Transition of Part of Speech,,,,詞類轉(zhuǎn)換是指把原文語言中的某一詞類轉(zhuǎn)譯為漢語的另一詞類。,一、轉(zhuǎn)換為漢語動詞 1、名詞轉(zhuǎn)換成動詞 英語中表達(dá)動作概念的動名詞、具有動作意義的抽象名詞、由動詞派生出來的名詞、

12、動詞加名詞構(gòu)成的固定短語、介詞加名詞構(gòu)成的固定短語等,往往可以根據(jù)具體情況譯成漢語動詞。 (1) The application of electronic computers makes for a tremendous rise in labor productivity. 使用電子計算機可以大大提高勞動生產(chǎn)率。,Transition of Part of Speech,,,,(2) Computers can pro

13、vide analysis of every operation in a factory. 計算機能對工廠的每道工序進行分析。(3) Primary forces have certain valuations that must be considered in any design. 在任何設(shè)計中,對于數(shù)值能確切計算的主要作用力都必須加以考慮。(4) Integrated circuits are fairl

14、y recent development. 集成電路是近年來發(fā)展起來的。,Transition of Part of Speech,,,,(5) Rockets have found application for the exploration of the universe.,(6) The sight and sound of our jet planes filled me with special longing.,火

15、箭已經(jīng)用來探索宇宙。,看到我們的噴氣式飛機,聽見隆隆的機聲,令我心馳神往。,Transition of Part of Speech,,,,(7) The lack of any special excretory system is explained in a similar way. (excretory:排泄的),(8) The 1976 UN document calls for the settlement of the M

16、iddle East conflict on the basis of Israeli withdrawal from occupied territories and Arab acknowledgement of Israeli’s right to exist.(n. → v.),植物沒有專門的排泄系統(tǒng),可用同樣的方式加以說明。(名詞轉(zhuǎn)譯)(n.→v.),1976年聯(lián)合國文件要求在以色列撤出所占的土地以及阿拉伯承認(rèn)以色列的生存權(quán)利

17、的基礎(chǔ)上解決中東沖突。,Transition of Part of Speech,,,,2、形容詞轉(zhuǎn)換成動詞 英語中某些由動詞轉(zhuǎn)換來的形容詞、同介詞搭配構(gòu)成句子表語或定語的形容詞、與連系動詞一起構(gòu)成復(fù)合謂語的形容詞,通常可譯成漢語中的動詞。(1) Copper wire is flexible. 銅線容易彎曲。(2) Television is different from radio in that it se

18、nds and receives pictures. 電視不同于無線電在于能發(fā)送并接收圖像。,Transition of Part of Speech,,,,(3) If extremely low-cost power were ever to become available from large nuclear power plants, electrolytic hydrogen would become comp

19、etitive. 如能從大型核電站獲得成本極低的電力,電解氫的競爭能力就會增強。(4) Heat is a form of energy into which all other forms are convertible. 熱是能的一種形式,其他一切能的形式都能轉(zhuǎn)化為熱能。,(5) The workers are confident that they will be able to build the mo

20、dern factory in a short time.,工人們確信在短期內(nèi)一定能建成這座現(xiàn)代化工廠。,Transition of Part of Speech,,,,3、介詞轉(zhuǎn)換成動詞 英語中的介詞或介詞短語在許多情況下可以譯成漢語的動詞,尤其是當(dāng)它們用作表語或狀語時。 The letter E is commonly used for electromotive force. 通常用字母E表示電動勢。(2)

21、Except for atomic energy, all forms of energy used by man are from the sun. 除原子能之外,人類所利用的一切形式的能量都來自太陽。,Transition of Part of Speech,,,,(3) So long as we have means of producing heat we can keep the steam engine at

22、 work. 只要能產(chǎn)生熱,就能使蒸汽機做功。,Transition of Part of Speech,,,,4、 副詞轉(zhuǎn)換成動詞 英語中有些作表語的副詞或復(fù)合賓語中的副詞,往往可譯成漢語的動詞。(1) The electric current flows through the circuit with the switch on. 如果開關(guān)接通,電流就流過線路。(2) Open the val

23、ve to let air in. 打開閥門,讓空氣進入。,Transition of Part of Speech,,,,(3) We are through with our test report. 我們的試驗報告寫完了。,我筆直地向前高速飛行,越過港口,飛臨海面。,(4) I barreled straight ahead, across the harbor and out over the sea. (ba

24、rrel:v.裝桶;[俚]高速開車/行駛;飛奔),Transition of Part of Speech,,,,二、轉(zhuǎn)換為漢語名詞 1、動詞轉(zhuǎn)換成名詞 英語中有些動詞在翻譯成漢語時很難找到相應(yīng)的動詞,這時可將其轉(zhuǎn)譯成漢語名詞 。(1) The electronic computer is chiefly characterized by its accurate and rapid computations.

25、 電子計算機的主要特點是計算準(zhǔn)確而快速。(2) An electric current varies directly as the electromotive force and inversely as the resistance. 電流的變化與電動勢成正比,與電阻成反比。,Transition of Part of Speech,,,,(3) The design aims at automatic opera

26、tion, easy regulation, simple maintenance and high productivity. 設(shè)計的目的在于自動操作,調(diào)節(jié)方便,維護簡易,生產(chǎn)率高。,(4) Formality has always characterized their relationship. (formality:拘謹(jǐn);禮節(jié);俗套),他們之間的關(guān)系,有一個特點,就是以禮相待。,Transition of Part o

27、f Speech,,,,(5) The earth on which we live is shaped a ball. (shape:使成形;摹制;仿造),(6) Most U.S. spy satellites are designed to burn up in the earth’s atmosphere after completing their missions.,我們居住的地球,形狀象一個大球。(動詞轉(zhuǎn)譯),美國絕大

28、多數(shù)間諜衛(wèi)星,按其設(shè)計,在完成使命后,在大氣層中焚毀。,Transition of Part of Speech,,,,2、形容詞轉(zhuǎn)換成名詞 英語中有些形容詞加上定冠詞the表示某一類人或物,漢譯時常譯成名詞。另外,英語中有些表示事物特征的形容詞作表語時,往往可在其后加上“性”、“度”、“體”等詞,譯成名詞。 (1) People are so much more flexible and inventive than

29、robots. 人類比機器人更靈活而且更富有創(chuàng)造性。(2) Some people think tomorrow's computers will be intelligent. 有人認(rèn)為未來的計算機就具有智能。,Transition of Part of Speech,,,,(3) In fission processes the fission fragments are very ra

30、dioactive. 在裂變過程中,裂變碎片具有強烈的放射性。,The doctor did his best to cure the sick and the wounded. 醫(yī)生盡了最大的努力來治療病號和傷員。(形容詞轉(zhuǎn)換)They were considered insincere. 他們被人認(rèn)為是偽君子。(insincere:不誠懇的;虛偽的;不可信任的),Transitio

31、n of Part of Speech,,,,3、代詞轉(zhuǎn)換成名詞 英語中的代詞譯成漢語,有時為了使譯文規(guī)范,須轉(zhuǎn)換為名詞 。(1) Radio waves are similar to light waves except that their wave-length is much greater. 無線電波與光波相似,只不過無線電波的波長更長一些。(2) The specific resistance o

32、f iron is not so small as that of copper. 鐵的電阻系數(shù)不如銅的電阻系數(shù)那樣小。,Transition of Part of Speech,,,,(3) Electricity may be produced by a generator which is turned by a motor using any of the other forms of energy.

33、 發(fā)電機可以發(fā)電,而發(fā)電機是由利用任何其他形式能量的原動機帶動的。,Transition of Part of Speech,,,,4、 副詞轉(zhuǎn)換成名詞 英語中有些副詞,在句子中用作狀語,譯成漢語時可根據(jù)具體情況轉(zhuǎn)換成漢語的名詞 。(1) The quality of the operating system determines how useful the computer is. 操作系統(tǒng)的質(zhì)量決

34、定著計算機的應(yīng)用效能。(2) Electromagnetic waves travel as fast as light. 電磁波傳播的速度和光一樣。 .,Transition of Part of Speech,,,,4、 副詞轉(zhuǎn)換成名詞(3) The instrument is used to determine how fully the batteries are charged. 這種儀

35、表用來確定電池充電的程度。(4) The device is shown schematically in Figure 1. 圖1所示為這種裝置的簡圖。,Transition of Part of Speech,,,,三、轉(zhuǎn)換為漢語形容詞 1、副詞轉(zhuǎn)換成形容詞(1) Robotics is so closely associated with cybernetics that it is sometimes

36、mistakenly considered to be synonymous. 機器人技術(shù)與控制論的聯(lián)系如此密切,以致兩者有時被錯誤地認(rèn)為是同一回事。(2) Miniature gas detector is chiefly featured by small size, light weight, complete functions and long continuous working time. 袖珍式瓦斯

37、檢測器的主要特點是體積小、重量輕、功能齊全、連續(xù)工作時間長。,Transition of Part of Speech,,,,(3) Gases and liquids are perfectly elastic. 氣體和液體都是完全的彈性體。,(4) In science and engineering, it is of great importance to state the laws and principle

38、s accurately.,(5)The sun affects tremendously both the mind and body of a man.,在理工科方面,定律和原理的準(zhǔn)確敘述非常重要。,太陽對人的身體和精神都有極大的影響。,Transition of Part of Speech,,,,2、名詞轉(zhuǎn)換成漢語形容詞 (1) The nuclear power system designed in China is of

39、great precision. 中國設(shè)計的核動力系統(tǒng)十分精確。(2) Electronic computers and microprocessors are of great importance to us. 電子計算機和微處理器對我們來說十分重要。 (3) Single crystals of high perfection are an absolute necessity for the fab

40、rication of integrated circuits. 高度完整的單晶對于制造集成電路來說是絕對必要的。,Transition of Part of Speech,,,,(4)The security and warmth of the destroyer’s sick bay were wonderful.(destroyer:破壞者;驅(qū)逐艦;bay:灣;[飛機的]艙;sick bay:船上病室/醫(yī)務(wù)室;船上醫(yī)療

41、設(shè)施的總稱),(5) It is no use employing radar to detect objects in water.,驅(qū)逐艦的病室很安全也很溫暖,好極了。,使用雷達(dá)探測水下目標(biāo)是沒有用的。,Transition of Part of Speech,,,,四、轉(zhuǎn)換成漢語副詞 1、形容詞轉(zhuǎn)換成漢語副詞 (1) The engine has given a constantly good performance.

42、 這臺發(fā)動機一直運轉(zhuǎn)良好。(2) The same principles of low internal resistance also apply to milliammeters. 低內(nèi)阻的原理同樣適用于毫安表。,Transition of Part of Speech,,,,1、形容詞轉(zhuǎn)換成漢語副詞 (3) A graph gives a visual representation of th

43、e relationship. 圖表可以直觀地顯示要說明的關(guān)系。 (4)It was a clear and unemotional exposition of the president’s reasons for willing to begin a Chinese-American dialogue. (n.→v.) 這篇發(fā)言清楚明白地、心平氣和地說明了總統(tǒng)希望開始中美對話的原因。(形容詞轉(zhuǎn)譯成副

44、詞)(unemotional:無感情的;不易動感情的;exposition:[事實、想法等的]闡述,講解;說明性的文章/講話),Transition of Part of Speech,,,,2、其他詞轉(zhuǎn)換成副詞(1) Rapid evaporation at the heating-surface tends to make the steam wet. 加熱面上的迅速蒸發(fā),往往使蒸汽的濕度加大。(2) The a

45、dded device will ensure accessibility for part loading and unloading. 增添這種裝置將保證工件裝卸方便。 (3) We shall develop the electric power industry in a way. 我們將大規(guī)模發(fā)展電力工業(yè)。,Transition of Part of Speech,,,,五、其他類型轉(zhuǎn)換 (

46、1)The President had prepared meticulously for his journey. 總統(tǒng)為這次出訪作了十分周密的準(zhǔn)備。(ad. →a.)(meticulously:過分注意細(xì)節(jié)的;謹(jǐn)小慎微的;一絲不茍地;嚴(yán)謹(jǐn)?shù)兀?) People should have some basic idea of how the things that they use do what they do. (how表

47、示手段),人們應(yīng)該對他們使用的工具的操作原理/方法有些基本的了解。,Transition of Part of Speech,,,,五、其他類型轉(zhuǎn)換(3) There is another conversation which from our point of view is equally important, and that is to do not with what is read but with how it is

48、read.(what表示閱讀內(nèi)容;how表示閱讀方法;point of view:mind),有另一種在我們看來是同等重要的談話,它與讀的內(nèi)容無關(guān),而與讀的方式相關(guān)。,Transition of Part of Speech,,,,五、其他類型轉(zhuǎn)換(4) In societies where social roles are rigidly determined, boys pattern their play after the

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