15544+自动化专业英语习题参考解答.docx

15544+自动化专业英语习题参考解答.docx

《15544+自动化专业英语习题参考解答.docx》由会员分享，可在线阅读，更多相关《15544+自动化专业英语习题参考解答.docx（68页珍藏版）》请在冰豆网上搜索。

15544+自动化专业英语习题参考解答

自动化专业英语

姜书艳主编

张昌华徐心皓何芳编著

习题参考解答

Unit1

A.BasiclawsofElectricalNetworks

[EX.1]Comprehension

1.KCL:

Thealgebraicsumofthecurrentsenteringanynodeiszero.

KVL:

Thealgebraicsumofthevoltagearoundanyclosedpathiszero.

2.Node:

Apointatwhichtwoormoreelementshaveacommonconnectioniscalledanode.

Branches:

asinglepathinanetworkcomposedofonesimpleelementandthenodeateachendofthatelement.

Path:

Ifnonodewasencounteredmorethanonce,thenthesetofnodesandelementsthatwehavepassedthroughisdefinedasapath.

Loop:

Ifthenodeatwhichwestartedisthesameasthenodeonwhichweended,thenthepathis,bydefinition,aclosedpathoraloop.apathisaparticularcollectionofbranches.

3.4,5,Wecanformapathbutnotaloop.

4.vR2=32V,Vx=6V

[EX.2]TranslationfromEnglishtoChinese

1.如果定义具有最大连接支路数的节点为参考节点，那么得到的方程相对来说比较简单。

2.我们发现分析的主要步骤是得到含有一个未知变量的方程，该未知变量是该节点对两端的电压。

3.然而，这个电阻相对于电路中其他的电阻来说是如此的小以至于我们可以在不引起明显误差的情况下忽略它的存在。

4.与其他方式相比,下面这种方式在列方程时不容易犯错误.在头脑中按顺时针方向沿闭合路径走一遍,如果首先遇到的是元件标有"+"号的端子,就直接写下它的电压;如果首先遇到的是标有"-"的端子,则写下该电压的负值。

5.正确分析电路的关键是先要在电路中规范地标出所有电压和电流。

6.仔细写出KCL和KVL方程就可以得到正确的关系式，必要的时候，比如未知量多余最初得到的方程数时再应用欧姆定律。

7.节点分析法基于基尔霍夫电流定律，运用节点分析法可以对不同的电路建立方程。

8.注意，为了保持一致性，式中把所有的电流源（定义为流入节点1）放在了方程左边，把所有经过电阻流出节点1的电流放到了方程右边。

9.在一个电路中，通过电阻的电压（称为压降），总有与电源极性相反的情况。

10.因为电子流过一个电阻时会失去能量，因此它们会以较低的能级出现。

[EX.3]TranslationfromChinesetoEnglish

1.Itshouldbeemphasizedthatthevoltagecannotbedefinedinasinglepoint-itisdefinedasthepotentialdifferencebetweentwopoints.

2.Notallofthegroundsaretheground;thisfactwillcausealotofsafetyissuesandelectricalnoise.

3.Butasthesecorrosivepipesareplacedbylower-cost,moremodernandmorenon-conductivePVCpipingsystem,thelowimpedancepathtothegroundwillnotexistanymore.

4.Kirchhoff'scurrentlawisbasedontheprincipleofconservationofcharge,andKirchhoff'svoltagelawisbasedonenergyconservationprinciple.Theyareboththebasiclawsofphysics.朗读

显示对应的拉丁字符的拼音

5.Ifthepublicportofthecircuitisnotconnectedwiththegroundthroughsomelow-impedancepath,itmayleadtosomepotentialdangers.

6.Sincethesamecurrentflowsthrougheachresistor,thevoltagedropsareproportionaltotheOhmicvaluesoftheresistor.

7.Ifallthevoltagedropsaroundaclosedloopareaddedandthenthistotalissubtractedfromthesourcevoltage,theresultiszero.

8.Whentheresistorvoltagesareaddedtogether,theirsumwillequalthesourcevoltage.Anynumberofresistorscanbeadded.

9.YoucanverifyKCLbyconnectingacircuitandmeasuringeachbranchcurrentandthetotalcurrentfromthesource.

10.Additionalresistorsconnectedinparallelwillfurtherreducetheresistanceandincreasethetotalcurrent.

[EX.4]Filloutthespaceaftertherecord.

Inanodal1thevariablesinthecircuitareselectedtobethenodevoltage.Thenodevoltagesaredefinedwithrespecttoa2pointinthecircuit.Onenodeisselectedasthe3node,andallothernodevoltagesare4withrespecttothatnode.Quiteoftenthisnodeistheonetowhichthelargestnumberof5areconnected.Itiscommonlycalled6becauseitissaidtobeatground-zero7,anditsometimesrepresentsthechassisorgroundlineinan8circuit.Wewillselectourvariablesasbeing9withrespecttothereferencenode.Ifoneormoreofthenodevoltagesareactuallynegativewithrespecttothereferencenode,theanalysiswill10it.

1.analysis2.common3.reference4.defined5.branches

6.ground7.potential8.practical9.positive10.indicate

B.TheCharacteristicsofBasicElements

[EX.1]Comprehension

1.Theinherentresistivityofamaterialandthedevicegeometrygovernedtheresistance.

2.Activeelementiscapableoffurnishinganaveragepowergreaterthanzerotosomeexternaldevice,butpassiveelementcannotsupplyanaveragepowerthatisgreaterthanzerooveraninfinitetimeinterval.

[EX.2]TranslationfromEnglishtoChinese

1.没有电子流过电容器的电介质，因为它是绝缘体。

2.在电路中所使用的电容值大多数都是在微法（μF的）和皮法（pF）量级的。

3.在任何绝缘的电容中都会有很小的电流流过，因此，电容上充的电最终都将流失。

4.当有电流流过一个电感时，就会产生磁场。

当电流值的改变，该磁场值也会随之改变。

5.自感应是一种因线圈中的电流变化而引起产生感应电压能力的度量。

6.当两个导体并排放置，它们之中总会产生一定的电容

7.电容和电感都是无源元件，只能储存和释放有限的能量。

8.任何实际元件都有一定的固有电阻、电容和电感，尽管在实际中它们可能很小。

9.我们需要记住的是，任何不互相接触的两个导电表面之间均存在非零的电容（尽管可能很小）。

10.电感两端的电压为零时仍然可以储存能量，例如当流过它的电流为恒定值时。

[EX.3]TranslationfromChinesetoEnglish

1.Rangeofcapacitorsandinductorscanbeverylarge,sosometimesitdeterminesthecircuitperformance,andsometimestheinfluenceisquitesmall.Withhigherandhigherworkingfrequencyofcomputerandcommunicationsystemsandagrowingnumberofintegratedcomponents,thisfeaturecannotbeignored.

2.Letusvisualizesomeexternaldeviceconnectedtothiscapacitorandcausingapositivecurrenttoflowintooneplateofthecapacitorandoutoftheotherplate.

3.Thepositivecurrententeringoneplaterepresentspositivechargemovingtowardthatplatethroughitsterminallead;thischargecannotpassthroughtheinteriorofthecapacitor,anditthereforeaccumulatesontheplate.

4.Eachcapacitorvoltageandeachinductorcurrentmustremainconstantduringtheswitchinginterval.

5.Afiniteamountofenergycanbestoredinacapacitorevenifthecurrentthroughthecapacitoriszero,suchaswhenthevoltageacrossitisconstant.

6.Whenweusetheprincipleofsuperposition,wemustregardtheinitialelectricvoltageandtheinitialinductorcurrentasindependentsources,andeachinitialvaluemustberemovedattheappropriatetime.

7.Acapacitorconsistsoftwoconductingsurfacesonwhichchargemaybestored,separatedbyathininsulatinglayerthathasaverylargeresistance.

8.Capacitorsinseriescombineasdoconductancesinseries,orresistorsinparallel.

9.Theinductorwhichisequivalenttoseveralinductorsconnectedinseriesisonewhoseinductanceisthesumoftheinductancesintheoriginalcircuit.Thisisexactlythesameresultweobtainedforresistorsinseries.

10.Thepresenceofalargevoltageacrossashortdistanceequatestoaverylargeelectricfield;thestoredenergyisdissipatedinionizingtheairinthepathofthearc.

[EX.4]Filloutthespaceaftertherecord.

Aninductorisbasicallya1ofwire.Thematerialaroundwhichthecoilisformediscalledthecore.Coilsarewoundoneither2ormagneticmaterials.Examplesofnonmagnetic3areair,wood,copper,plastic,andglass.Thepermeabilitiesofthesematerialsarethesameasfora4.Examplesofmagneticmaterialsareiron,5,steel,cobalt,oralloys.Thesematerialshavepermeabilitiesthatare6orthousandsoftimesgreaterthanthatofavacuumandare7asferromagnetic.Aferromagneticcore8abetter9forthemagneticlinesofforceandthuspermitsastrongermagnetic10.

1.coil2.nonmagnetic3.materials4.vacuum5.nickel

6.hundreds7.classified8.provides9.path10.field

Unit2

A.DigitalCircuits

[EX.2]TranslationfromEnglishtoChinese

1.同样，极少数因为热运动而产生的少数载流子穿过结亦形成电流，但这些电流在一个正向偏置二极管的总电流当中微不足道，因此也没有画出。

2.当集电极-发射极电压维持很小时，晶体管中欧姆必电阻（尤其是轻掺杂的集电极）变得很重要。

3.多数情况下两个区是等同的，可以对器件不做任何修改就进行互换，它们是对称的。

4.这种情况一旦发生，不管漏-源电压是多少，都没有任何电流能通过晶体管，晶体管被称为截止。

5.沟道两端的电压降不会随着漏极电压的增加而无限增加，实际上夹断区会变宽，因此漏极电流会达到上限。

6.我们还发现，MOSFET电路在低频率时输入阻抗的基本上是无限的，这意味着零输入偏置电流。

7.增强型MOSFET实际上有一个沟道，使得只有当电源给门上加了合适的偏置，才有电流流过。

8.我们可以把它想象成一个N型半导体，其中有适量的电子作为载流子，然后在它的一边放上一块P型半导体。

9.因为NPN型晶体管中有两个PN结，所以这种晶体管由两个内在阳极连接在一起的二极管组成。

10.一种非常有用且简单的测试双击晶体管好坏的方法是，用欧姆表连接晶体管的任意两端并观察电阻值。

[EX.3]TranslationfromChinesetoEnglish

1.Thejunctiondiode,thebipolarjunctiontransistor,andtheMOStransistorarethethreemostimportantsemiconductordevices.Togetherwithresistorsandcapacitors,theyformthevastmajorityoftheelementsusedinmodernintegratedcircuits.

2.MOStransistorsarenormallyconsideredmajoritycarrierdevices,whichconductonlyafterachannelforms.

3.Inthesaturationregion,thecollector-emittervoltageremainssosmallthatthecollector-basejunctionisslightlyforward-biased.

4.Acollectorcurrent100timeslargerthanthebasecurrentflowsacrossthebase-collectorjunctioneventhoughthisjunctionremainsreversebiased.

5.Moreandmoremajoritycarriersmakethetransitacrossthedepletionregionwithoutbeingsweptbackbytheelectricfield.

6.Theelectricalcharacteristicsofthetransistorcanberepresentedontwographs,consideredtheinputcharacteristicandtheoutputcharacteristic.

7.Abadtransistoroftenexhibitsalowresistanceinbothsenses（ashortedjunction）orahighresistanceinbothsenses（anopenjunction）.

8.AP-typesemiconductorhasholesthatbehavelikepluschargesasthemajoritychargecarrier.

9.Inthesetransistors,conductionoccursinachannelformedinn-typebulkmaterialviapositivechargecarriers.

10.NoticethatthecurrentIDisplottedversusthedrain-sourcevoltageVDSacrossthedevice.

[EX.4]Filloutthespaceaftertherecord.

Whenadrain-sourcevoltageincreasesfurther,however,somethingrathersurprisinghappens:

the1currentlevelsoffandremainsvirtuallyconstantwithincreasingVDS.Thereasonisavoltagedrop（IRdrop）alongthe2N-channelmaterial.Ifthegateisatground3（relativetosource）andthe4regionnearthetopofthebarisatavoltageVDS,thegateis5relativetothechannelbyaboutthisvoltage.Thus,thegate-channeldiode6isreversebiasedbytheamountVDS,andalargedepletionzoneis7thattendstopinchoffthechannel.However,thecurrentdoesnotstopbecausetheIR8wouldthenvanishandthechannelwouldopenagain;instead,a9channelformsthatbecomesl