軌道交通車輛專業(yè)英語課件：Constructure of AC Electric Locomotive

ConstructureofACElectricLocomotiveRailwayVehicleEnglishPart1:ReadingMaterialFig.2-3PartsofanACelectriclocomotivePart1:ReadingMaterialTheFig.2-3showsanACelectriclocomotive,i.e.,alocomotivecollectingACpowerfromanoverheadline.Thecurrentpassesdirectlyfromthepantograph(orshoe)tothemainandauxiliaryinverters.Part1:ReadingMaterial1.ElectronicControls

Almosteverypartofthemodernlocomotive’sequipmenthassomeformofelectroniccontrol.Theyareusuallycollectedinacontrolcubiclenearthecabforeasyaccess.Thecontrolswillusuallyincludeamaintenancemanagementsystemofsomesortwhichcanbeusedtodownloaddatatoaportableorhand-heldcomputer.2.Pinion/Gear

Thetractionmotordrivestheaxlethroughareductiongearofarangebetween3to1(freight)and4to1(passenger).Part1:ReadingMaterial3.AsynchronousMotor

ModerntractionmotortypeusethreephaseACelectricalsupplyandnowthefavoureddesignformoderntraintractionsystemscanbeusedonDCandACelectrifiedrailwayswithsuitablecontrolelectronicsandonelectriclocomotives.4.AxleBrush

Themeansbywhichthepowersupplycircuitiscompletedwiththesubstationoncepowerhasbeendrawnonthelocomotive.Currentcollectedfromtheoverheadlineorthirdrailisreturnedviatheaxlebrushandoneoftherunningrails.Part1:ReadingMaterial5.Battery

Alltrainsareprovidedwithabatterytoprovidestart-upcurrentandforsupplyingessentialcircuits,suchasemergencylighting,whenthelinesupplyfails.ThebatteryisusuallyconnectedacrosstheDCcontrolsupplycircuit.6.CircuitBreaker

Anelectrictrainisalmostalwaysprovidedwithsomesortofcircuitbreakertoisolatethepowersupplywhenthereisafault,orformaintenance.OnACsystemstheyareusuallyontheroofnearthepantograph.Therearetwotypes—theairblastcircuitbreakerandthevacuumcircuitbreakerorVCB.Theairorvacuumpartisusedtoextinguishtheairwhichoccursasthetwotipsofthecircuitbreakerareopened.Part1:ReadingMaterial7.Converter

Generictermforanysolidstateelectronicsystemforconvertingalternatingcurrenttodirectcurrentorviceversaisconverter.WhereanACsupplyhastobeconvertedtoDCitiscalledarectifierandwhereDCisconvertedtoACitiscalledaninverter.ThewordoriginatedintheUSbutisnowcommonelsewhere.8.CoolingFansTokeepthethyristorsandotherelectronicpowersystemscool,theinteriorofamodernlocomotiveisequippedwithanairmanagementsystem,electronicallycontrolledtokeepallsystemsoperatingatthecorrecttemperature.Thefansarepoweredbyanauxiliaryinverterproducing3-phaseACatabout400V.Part1:ReadingMaterial9.DCLinkUsedonmodemelectronicpowersystemsbetweenthesinglephaserectifierandthe3-phaseinverter,itiseasiertoconvertthesinglephaseACfromtheoverheadlinetothe3-phaserequiredforthemotorsbyrectifyingittoDCandtheninvertingtheDCto3-phaseAC.10.Inverter

Electronicpowerdevicemountedontrainstoprovidealternatingcurrentfromdirectcurrent.PopularnowadaysforDCrailwaystoallowthree-phasedriveorforauxiliarysupplieswhichneedanACsupply.Part1:ReadingMaterial11.LineBreaker

Electro-mechanicalswitchinatractionmotorpowercircuitisusedtoactivateordisablethecircuit.Itisnormallyclosedtostartthetrainandremainsclosedallthetimepowerisrequired.Itisopenedbyacommandfromthedrivingcontroller,no-voltsdetected,overloaddetectedand(wererequired)wheelspinorslidedetected.Itislinkedtotheoverloadandno-voltcontrolcircuitssothatitfunctionsasaprotectivecircuitbreaker.12.MasterController

Driver'spowercontroldeviceislocatedinthecab.Thedrivermovesthehandleofthemastercontrollertoapplyorreducepowertothelocomotiveortrain.Part1:ReadingMaterial13.MotorBlowers

Tractionmotorsonelectriclocomotivesgetveryhotand,tokeeptheirtemperatureatareasonablelevelforlongperiodsofhardwork,theyareusuallyfittedwithelectricfanscalledmotorblowers.Onamodernlocomotive,theyarepoweredbyanauxiliary3-phaseACsupplyofaround400Vsuppliedbyanauxiliaryinverter.14.Rectifier

AconverterconsistingofthyristorsanddiodesisusedtoconvertACtoDC.Amodernlocomotivewillusuallyhaveatleasttwo,oneforthepowercircuitsandoneormorefortheauxiliarycircuits.Part1:ReadingMaterial16.SandBox

Locomotivesalwayscarrysandtoassistadhesioninbadrailconditions,andisoftenprovidedonmultipleunittraintoo.17.SynchronousMotor

Tractionmotorwherethefieldcoilsaremountedonthedriveshaftandthearmaturecoilsinthehousing,theinverseofnormalpractice.Thisisasingle-phasemachinecontrolledbysimpleinverter.Nowsupersededbytheasynchronousmotor.Part1:ReadingMaterial18.Transformer

Asetofwindingswithamagneticcoreisusedtostepdownorstepupavoltagefromoneleveltoanother.Thevoltagedifferencesaredeterminedbytheproportionofwindingsontheinputsidecomparedwiththeproportionontheoutputside.AnessentialrequirementforlocomotivesandtrainsusingACpower,wherethelinevoltagehastobesteppeddownbeforeusedonthetrain.19.Pantographs

Currentiscollectedfromoverheadlinesbypantographs,asshowninFig.2-4.Pantographsareeasyintermsofisolation—youjustlowerthepantolosethepowersupplytothevehicle.However,itiscomplicatedtooperate.Part1:ReadingMaterial

Sincethepantographisusuallythesinglepointpowercontactforthelocomotiveorpowercar,itmustmaintaingoodcontactunderallrunningconditions.Thehigherthespeed,themoredifficultthemaintenanceofgoodcontact.Wehavealreadymentionedtheproblem(above)ofawavebeingformedinthewirebyapantographmovingathighspeed.Fig.2-4PantographPart1:ReadingMaterialPantographcontactismaintainedeitherbyspringorairpressure.Compressedairpressureispreferredforhigh-speedoperation.Thepantographisconnectedtoapistoninacylinderandairpressureinthecylindermaintainsthepantographintheraisedcondition.RailwayVehicleEnglishPart2：VocabularyPart2:Vocabularythyristor半導(dǎo)體閘流管sandbox砂箱transformer變壓器axlebrush軸刷pantograph受電弓vacuumcircuitbreaker(VCB)真空斷路器asynchronousmotor異步電動(dòng)機(jī)auxiliaryinverter逆變器electroniccontrol電氣控制Part3:CommentariesforLongDifficultSentencesRailwayVehicleEnglishPart3:CommentariesforLongDifficultSentences123Currentcollectedfromtheoverheadlineorthirdrailisreturnedviatheaxlebrushandoneoftherunningrails.

從架空線路或第三軌道收集的電流通過軸刷和其中一個(gè)運(yùn)行軌道返回。Tractionmotorwherethefieldcoilsaremountedonthedriveshaftandthearmaturecoilsinthehousing,theinverseofnormalpractice.

牽引電機(jī)的磁場(chǎng)線圈安裝在傳動(dòng)軸上，電樞線圈安裝在外殼上，這與正常的做法相反。Tokeepthethyristorsandotherelectronicpowersystemscool,theinteriorofamodernlocomotiveisequippedwithanairmanagementsystem,electronicallycontrolledtokeepallsystemsoperatingatthecorrecttemperature.為了保持晶閘管和其他電子電力系統(tǒng)的冷卻，現(xiàn)代機(jī)車的內(nèi)部配備了空氣管理系統(tǒng)，由電子控制，以保持所有系統(tǒng)在正確的溫度下運(yùn)行。Part3:CommentariesforLongDifficultSentences45Theaircompressorisrequiredtoprovideaconstantsupplyofcompressedairforthelocomotiveandtrainbrakes.空氣壓縮機(jī)需要為機(jī)車和列車的制動(dòng)器提供持續(xù)的壓縮空氣供應(yīng)。

Sincethepantographisusuallythesinglepointpowercontactforthelocomotiveorpowercar,itmustmaintaingoodcontactunderallrunningconditions.由于受電弓通常是機(jī)車或動(dòng)力車的單點(diǎn)電源接觸點(diǎn)，因此在所有運(yùn)行條件下都必須保持良好的接觸RailwayVehicleEnglishPart4:ExerciseandActivityPart4:ExerciseandActivityDirections：Explainthemeaningsandfunctionsofthefollow