研究生專(zhuān)業(yè)外語(yǔ)三單元課件.ppt

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

2、態(tài)的，接通的，開(kāi)態(tài) off-state a. 關(guān)態(tài)的，斷開(kāi)的，斷態(tài)的 microamp n. 微安 milliamp n. 毫安,Words,waveform n. 波形 zero-voltage 電壓過(guò)零的 zero-current 電流過(guò)零的,Words,1The 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 the los

3、ses in the transition states.,開(kāi)關(guān)損耗是很大的，但可以控制。開(kāi)關(guān)損耗進(jìn)一步可以分解成三個(gè)部分：接通狀態(tài)、關(guān)斷狀態(tài)和變換狀態(tài)的損耗。,Notes,2The practical switching devices have limited capabilities of rate of voltage transition and the rate of current steering. These nonabrupt transition ratesgive rise to power losses in the switching devices. We wil

4、l examine these switching losses in two cases separately: the inductive and capacitive loads.,實(shí)際開(kāi)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(kāi)關(guān)裝置的功率損失。我們將分別從感性負(fù)載和容性負(fù)載兩種情況來(lái)分析開(kāi)關(guān)損耗。,Notes,3The switching power losses increase linearly with the switching frequency like in the resistive case but about six times more. The u

5、pper bound on the switching frequency is also about half.,類(lèi)似于電阻負(fù)載的情況，開(kāi)關(guān)功率損耗隨著開(kāi)關(guān)頻率線性增大，但大約為電阻負(fù)載情況的6倍多。開(kāi)關(guān)頻率的上限也約為一半。,Notes,4The 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 current through the

6、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(kāi)關(guān)開(kāi)始處于閉合狀態(tài)，則通過(guò)開(kāi)關(guān)的電流為IS。電容器的電壓為Uo，開(kāi)關(guān)兩端的電壓為零，二極管V1反向偏置。,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 Elec

7、tronics 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 (SCR: 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(chǎng)效應(yīng)晶體管 (Metal Oxide Semiconductor Field Effect Transistor) GTO 門(mén)極可關(guān)

8、斷晶閘管 (Gate-Turn-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(lèi)轉(zhuǎn)換是指把原文語(yǔ)言中的某一詞類(lèi)轉(zhuǎn)譯為漢語(yǔ)的另一詞類(lèi)。,一、轉(zhuǎn)換為漢語(yǔ)動(dòng)詞 1、名詞轉(zhuǎn)換成動(dòng)詞 英語(yǔ)中表達(dá)動(dòng)作概念的動(dòng)名詞、具有動(dòng)作意義的抽象名詞、由動(dòng)詞派生出來(lái)的名詞、動(dòng)詞加名詞構(gòu)成的固定短語(yǔ)、介詞加名詞構(gòu)成的固定短語(yǔ)等，往往可以根據(jù)具體情況譯成漢語(yǔ)動(dòng)詞。 (1) The application of electronic

9、computers makes for a tremendous rise in labor productivity. 使用電子計(jì)算機(jī)可以大大提高勞動(dòng)生產(chǎn)率。,Transition of Part of Speech,(2) Computers can provide analysis of every operation in a factory. 計(jì)算機(jī)能對(duì)工廠的每道工序進(jìn)行分析。 (3) Primary forces have certain valuations that must be considered in any design. 在任何設(shè)計(jì)中，對(duì)于數(shù)值能確切計(jì)算的主要作用力

10、都必須加以考慮。 (4) Integrated circuits are fairly recent development. 集成電路是近年來(lái)發(fā)展起來(lái)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.,火箭已經(jīng)用來(lái)探索宇宙。,看到我們的噴氣式飛機(jī)，聽(tīng)見(jiàn)隆隆的機(jī)聲，令我心馳神往。,Transit

11、ion 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 Middle East conflict on the basis of Israeli withdrawal from occupied territories and Arab acknowledgement of Israelis right to e

12、xist.（n. v.）,植物沒(méi)有專(zhuān)門(mén)的排泄系統(tǒng)，可用同樣的方式加以說(shuō)明。（名詞轉(zhuǎn)譯）（n.v.）,1976年聯(lián)合國(guó)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(dòng)詞 英語(yǔ)中某些由動(dòng)詞轉(zhuǎn)換來(lái)的形容詞、同介詞搭配構(gòu)成句子表語(yǔ)或定語(yǔ)的形容詞、與連系動(dòng)詞一起構(gòu)成復(fù)合謂語(yǔ)的形容詞，通?？勺g成漢語(yǔ)中的動(dòng)詞。 (1) Copper wire is flexible. 銅線容易彎曲。 (2) Television is different from radio in that it sends a

13、nd receives pictures. 電視不同于無(wú)線電在于能發(fā)送并接收?qǐng)D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 competitive. 如能從大型核電站獲得成本極低的電力，電解氫的競(jìng)爭(zhēng)能力就會(huì)增強(qiáng)。 (4) Heat is a form of energy into which all other form

14、s 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 modern 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(dòng)詞 英語(yǔ)中的介詞或介詞短語(yǔ)在許多情況下可以譯成漢語(yǔ)的動(dòng)詞，尤其是當(dāng)它們用作表語(yǔ)或狀語(yǔ)時(shí)。 The letter E is commonly used for electromotive forc

15、e. 通常用字母E表示電動(dòng)勢(shì)。 (2) Except for atomic energy, all forms of energy used by man are from the sun. 除原子能之外，人類(lèi)所利用的一切形式的能量都來(lái)自太陽(yáng)。,Transition of Part of Speech,(3) So long as we have means of producing heat we can keep the steam engine at work. 只要能產(chǎn)生熱，就能使蒸汽機(jī)做功。,Transition of Part of Speech,4、 副詞轉(zhuǎn)換成動(dòng)詞 英語(yǔ)中有些作

16、表語(yǔ)的副詞或復(fù)合賓語(yǔ)中的副詞，往往可譯成漢語(yǔ)的動(dòng)詞。 (1) The electric current flows through the circuit with the switch on. 如果開(kāi)關(guān)接通，電流就流過(guò)線路。 (2) Open the valve to let air in. 打開(kāi)閥門(mén)，讓空氣進(jìn)入。,Transition of Part of Speech,(3) We are through with our test report. 我們的試驗(yàn)報(bào)告寫(xiě)完了。,我筆直地向前高速飛行，越過(guò)港口，飛臨海面。,(4) I barreled straight ahead, acros

17、s the harbor and out over the sea. （barrel：v.裝桶；俚高速開(kāi)車(chē)/行駛；飛奔）,Transition of Part of Speech,二、轉(zhuǎn)換為漢語(yǔ)名詞 1、動(dòng)詞轉(zhuǎn)換成名詞 英語(yǔ)中有些動(dòng)詞在翻譯成漢語(yǔ)時(shí)很難找到相應(yīng)的動(dòng)詞，這時(shí)可將其轉(zhuǎn)譯成漢語(yǔ)名詞 。 (1) The electronic computer is chiefly characterized by its accurate and rapid computations. 電子計(jì)算機(jī)的主要特點(diǎn)是計(jì)算準(zhǔn)確而快速。 (2) An electric current varies directl

18、y as the electromotive force and inversely as the resistance. 電流的變化與電動(dòng)勢(shì)成正比，與電阻成反比。,Transition of Part of Speech,(3) The design aims at automatic operation, easy regulation, simple maintenance and high productivity. 設(shè)計(jì)的目的在于自動(dòng)操作，調(diào)節(jié)方便，維護(hù)簡(jiǎn)易，生產(chǎn)率高。,(4) Formality has always characterized their relationship

19、. （formality：拘謹(jǐn)；禮節(jié)；俗套）,他們之間的關(guān)系，有一個(gè)特點(diǎn)，就是以禮相待。,Transition of Part of 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 earths atmosphere after completing their missions.,我們居住的地球，形狀象一個(gè)大球。（動(dòng)詞轉(zhuǎn)譯）,美國(guó)絕大多數(shù)間諜衛(wèi)星，按其設(shè)計(jì)，在完成使命后，在大

20、氣層中焚毀。,Transition of Part of Speech,2、形容詞轉(zhuǎn)換成名詞 英語(yǔ)中有些形容詞加上定冠詞the表示某一類(lèi)人或物，漢譯時(shí)常譯成名詞。另外，英語(yǔ)中有些表示事物特征的形容詞作表語(yǔ)時(shí)，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 robots. 人類(lèi)比機(jī)器人更靈活而且更富有創(chuàng)造性。 (2) Some people think tomorrows computers will be intelligent. 有人認(rèn)為未來(lái)的計(jì)算機(jī)就具有智能。,Trans

21、ition of Part of Speech,(3) In fission processes the fission fragments are very radioactive. 在裂變過(guò)程中，裂變碎片具有強(qiáng)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(lái)治療病號(hào)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(chéng)懇的；虛偽的；不可信任的）,Transition of Part of Speech,3、代

22、詞轉(zhuǎn)換成名詞 英語(yǔ)中的代詞譯成漢語(yǔ)，有時(shí)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(wú)線電波與光波相似，只不過(guò)無(wú)線電波的波長(zhǎng)更長(zhǎng)一些。 (2) The specific resistance of 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 produ

23、ced by a generator which is turned by a motor using any of the other forms of energy. 發(fā)電機(jī)可以發(fā)電，而發(fā)電機(jī)是由利用任何其他形式能量的原動(dòng)機(jī)帶動(dòng)的。,Transition of Part of Speech,4、 副詞轉(zhuǎn)換成名詞 英語(yǔ)中有些副詞，在句子中用作狀語(yǔ)，譯成漢語(yǔ)時(shí)可根據(jù)具體情況轉(zhuǎn)換成漢語(yǔ)的名詞 。 (1) The quality of the operating system determines how useful the computer is. 操作系統(tǒng)的質(zhì)量決定著計(jì)算機(jī)的應(yīng)用效能。 (2

24、) 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. 這種儀表用來(lái)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(jiǎn)圖。,Transition of Part of Speech,三、轉(zhuǎn)換為漢語(yǔ)

25、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 mistakenly considered to be synonymous. 機(jī)器人技術(shù)與控制論的聯(lián)系如此密切，以致兩者有時(shí)被錯(cuò)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

26、斯檢測(cè)器的主要特點(diǎn)是體積小、重量輕、功能齊全、連續(xù)工作時(shí)間長(zhǎng)。,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 principles accurately.,(5)The sun affects tremendously both the mind and body of a man.,在理工科方面，定律和原

27、理的準(zhǔn)確敘述非常重要。,太陽(yáng)對(duì)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(yǔ)形容詞 (1) The nuclear power system designed in China is of great precision. 中國(guó)設(shè)計(jì)的核動(dòng)力系統(tǒng)十分精確。 (2) Electronic computers and microprocessors are of great importance to us. 電子計(jì)算機(jī)和微處理器對(duì)我們來(lái)說(shuō)十分重要。 (3) Single crystals of high perfection are a

28、n absolute necessity for the fabrication of integrated circuits. 高度完整的單晶對(duì)于制造集成電路來(lái)說(shuō)是絕對(duì)必要的。,Transition of Part of Speech,(4)The security and warmth of the destroyers sick bay were wonderful. （destroyer：破壞者；驅(qū)逐艦；bay：灣；飛機(jī)的艙；sick bay：船上病室/醫(yī)務(wù)室；船上醫(yī)療設(shè)施的總稱(chēng)）,(5) It is no use employing radar to detect objects i

29、n 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(cè)水下目標(biāo)是沒(méi)有用的。,Transition of Part of Speech,四、轉(zhuǎn)換成漢語(yǔ)副詞 1、形容詞轉(zhuǎn)換成漢語(yǔ)副詞 (1) The engine has given a constantly good performance. 這臺(tái)發(fā)動(dòng)機(jī)一直運(yùn)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

30、語(yǔ)副詞 (3) A graph gives a visual representation of the relationship. 圖表可以直觀地顯示要說(shuō)明的關(guān)系。 (4)It was a clear and unemotional exposition of the presidents 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(shuō)明了總統(tǒng)希望開(kāi)始中美對(duì)話的原因。（形容詞轉(zhuǎn)譯成副詞） （unemotional：無(wú)感情的；不易動(dòng)感情的；exposition：事實(shí)、想法等的闡述，講解；說(shuō)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 added device will ensure accessibility fo