电气工程专业英语+unt1

电气工程及其自动化专业英语主编杨勇邓秋玲CONTENTSUnit1FundamentalsofElectronicCircuitsUnit2PowerElectronicsUnit3ElectricalMachinesUnit4ElectricPowerSystemsUnit5ElectricPowerGenerationsUnit6AutomaticControlUnit7SensoringTechnologyUnit8ComputerNetworkandNetworkedControlUnit9SignalProcessingUnit1FundamentalsofElectronicCircuits1.1IntroductiontoCircuitTheory1.2AnalogandDigitalCircuits1.3Three-PhaseCircuits1.4FurtherReading1.1IntroductiontoCircuitTheoryNewWordsandExpressionselementn.成分；元件interconnectvt.使互相连接noden.节点branchn.分枝；分部；支流v.出现分歧loopn.循环，回路;vt.使成环；topologyn.拓扑；布局；拓扑学configurationn.构造；结构；配置；外形terminaln.终点站；终端；接线端1.1IntroductiontoCircuitTheoryNewWordsandExpressionsresistorn.[电]电阻器independentadj.独立自主的；不受约束的seriesn.连续；系列；级数；串联paralleladj.平行的；并联的n.平行线；平行面；v.相应；平行impedancen.[电]阻抗；全电阻；[物]阻抗theoremn.[数]定理；法则Note：③：providingoneormoreclosedpaths为network的后置定语。1.1IntroductiontoCircuitTheorytextNote：①：differentiate在此处为动词，differentiatebetweenAandB表示区分A和B；Todifferentiatebetweenacircuitandanetwork是目的状语从句.Note：②：regard…as表示“把…认为”(1)Nodes,BranchesandLoopsSincetheelementsofanelectriccircuitcanbeinterconnectedinseveralways,weneedtounderstandsomebasicconceptsofnetworktopology.Todifferentiatebetweenacircuitand①anetwork,wemayregardanetworkas②aninterconnectionofelementsordevices,whereasacircuitisanetworkprovidingoneormoreclosedpaths③.1.1IntroductiontoCircuitTheorytextInnetworktopology,westudythepropertiesrelatingto(关于...的特性)theplacementofelementsinthenetworkandthegeometricconfigurationofthenetwork.Suchelementsincludebranches,nodes,andloops.Abranchrepresentsasingleelementsuchasavoltagesourceoraresistor.Inotherwords,abranchrepresentsanytwo-terminalelement.ThecircuitinFig.1.1hasfivebranches,namely,the10Vvoltagesource,the2Acurrentsource,andthethreeresistors.Anodeisthepointofconnectionbetweentwoormorebranches.1.1IntroductiontoCircuitTheorytextAnodeisusuallyindicatedbyadotinacircuit.Ifashortcircuit(aconnectingwire)connectstwonodes,thetwonodesconstituteasinglenode.ThecircuitinFig.1.1hasthreenodesa,b,andc.Noticethatthethreepointsthatformnodeb①areconnectedbyperfectlyconductingwiresandthereforeconstituteasinglepoint.Note:①threepointsthatformnodeb表示形成节点b的3个点.此句可译为:注意到形成节点b的3个点是通过理想导线相连接的，因此组成了1个节点.1.1IntroductiontoCircuitTheorytextThesameistrueof①thefourpointsformingnodec.Wedemonstratethat(证明)thecircuitinFig.1.1hasonlythreenodesbyredrawingthecircuitinFig.1.2.ThetwocircuitsinFig.1.1andFig.1.2areidentical.However,forthesakeofclarity②,nodesbandcarespreadout③withperfectconductorsasinFig.1.2.Note:①：thesameistrueof:这也适用于…，…也是如此。Note:②：forthesakeofclarity:为清楚起见;③：spreadout:伸展;spreadoutwithperfectconductors：用理想导线分散开。1.1IntroductiontoCircuitTheorytextAloopisanyclosedpathinacircuit.Aloopisaclosedpathformedbystartingatanode,passingthroughasetofnodes,andreturningtothestartingnodewithoutpassingthroughanynodemorethanonce①.Aloopissaidtobe（可认为是）independentifitcontainsabranchwhichisnotinanyotherloop.Independentloopsorpathsresultin（导致,结果是）independentsetsofequations.Note:①：回路是一个闭合的路径，它是从一个节点开始，经过若干节点，再回到起始节点，任意一个节点只经过一次。1.1IntroductiontoCircuitTheorytextForexample,theclosedpathabcacontainingthe2Ωresistor①inFig.1.2isaloop.Anotherloopistheclosedpathbcbcontainingthe3Ωresistorandthecurrentsource.AlthoughonecanidentifysixloopsinFig.1.2,onlythreeofthemareindependent.Anetworkwithbbranches,nnodes,andlindependentloopswillsatisfythefundamentaltheoremofnetworktopology:b=l+n-1(1.1)Note：①containingthe2Ωresistor作定语修饰closedpathabca，意为包含2Ω电阻的闭合路径abca。1.1IntroductiontoCircuitTheorytextAsthenexttwodefinitionsshow,circuittopologyisofgreatvalue（=isveryvaluable）tothestudyofvoltagesandcurrentsinanelectriccircuit.Twoormoreelementsareinseries（串联）iftheyarecascadedorconnectedsequentially（接顺序连接）andconsequentlycarrythesamecurrent（流过相同电流）.Twoormoreelementsareinparallel（并联）iftheyareconnectedtothesametwonodesandconsequentlyhavethesamevoltageacrossthem①.Note:①：voltageacrossthem表示关于两节点之间的电压，“them”指代“twonodes”。1.1IntroductiontoCircuitTheorytextElementsmaybeconnectedinawaythattheyareeitherinseriesorinparallel.InthecircuitshowninFig.1.1,thevoltagesourceandthe5Ωresistorareinseriesbecausethesamecurrentwillflowthrough①them.The2Ωresistor,the3Ωresistor,andthecurrentsourceareinparallelbecausetheyareconnectedtothesametwonodes(bandc)andconsequentlyhavethesamevoltageacrossthem②.The5Ωand2Ωresistorsareneitherinseriesnorinparallelwitheachother.Note：①：修饰电流的介词短语用through，②：修饰电压用across。them代表resistors1.1IntroductiontoCircuitTheorytext(2)Ohm’sLaw，Kirchhoff’sCurrentLaw(KCL)andKirchhoff’sVoltageLaw(KVL)Ohm’sLawstatesthevoltageacrossaresistor,R(orimpedance,Z)isdirectlyproportionalto（与...成比例）thecurrentpassingthroughit(theresistance/impedanceistheproportionalityconstant).(1.2)Note:①：proportionalityconstant是比例系数。②：DC:表示directcurrent;AC表示alternatingcurrent。DC:AC:viRVIZ1.1IntroductiontoCircuitTheorytextOhm’sLawbyitself①isnotsufficienttoanalyzecircuits.However,whenitiscoupledwith②Kirchhoff’stwolaws,wehaveasufficient,powerfulsetoftoolsforanalyzingalargevarietyofelectriccircuits.Kirchhoff’slawswerefirstintroducedin1847bytheGerman