電力技術(shù)術(shù)語

ACAlternatingCurrent(AC)iselectriccurrentthatalternatesbetweenapositivemaximumvalueandanegativemaximumvalueatacharacteristicfrequency,usually50or60cyclespersecond(Hertz).交流交流是指電流在正負(fù)最大值之間以特定的頻率變動，通常頻率為50或60赫茲。我國工頻為50Hz。ActivePowerActivepoweristherealpower(kW)suppliedbythegeneratorsettotheelectricalload.Activepowercreatesaloadonthegeneratorset'sengineandislimitedbythehorsepoweroftheengine.Activepowerdoestheworkofheating,turningmotorshafts,etc.有功功率有功功率(kW)，是指發(fā)電機組實際供應(yīng)給負(fù)載的功率，它由發(fā)電機組的發(fā)動機提供，受到發(fā)動機馬力大小的限制。發(fā)熱和驅(qū)動馬達轉(zhuǎn)動靠有功功率完成。AmortisseurWindingsTheamortisseurwindingsofasynchronousACgeneratoraretheconductorsembeddedinthepolefacesoftherotor.Theyareconnectedtogetheratbothendsofthepolesbyendringsorendplates.Theirfunctionistodampenwaveformdistortionduringloadchanges.阻尼線圈同步交流發(fā)電機的阻尼線圈是指嵌繞在轉(zhuǎn)子磁極間的導(dǎo)線，他們分別在兩極用端環(huán)或端板相連接，主要功能是減弱因負(fù)載變化而引起的波形畸變。AmpacityAmpacityisthesafecurrent-carryingcapacityofanelectricalconductorinamperesasdefinedbycode載流容量載流容量是以安培數(shù)來定義導(dǎo)線安全載流能力。AmpereTheampereisaunitofelectriccurrentflow.Oneampereofcurrentwillflowwhenapotentialofonevoltisappliedacrossaresistanceofoneohm.安培安培是電流單位。1伏電壓作用于1歐姆的電阻上就會產(chǎn)生1安培的電流。ApparentPowerApparentpoweristheproductofcurrentandvoltage,expressedaskVA.Itisrealpower(kW)dividedbythepowerfactor(PF)視在功率視在功率是電流和電壓共同作用的產(chǎn)物，用kVA表示。它等于有功功率(kW)除以功率因數(shù)。ArmatureThearmatureofanACgeneratoristheassemblyofwindingsandmetalcorelaminationsinwhichtheoutputvoltageisinduced.Itisthestationarypart(stator)inarevolving-fieldgenerator.電樞交流發(fā)電機電樞的是金屬芯和繞組的總成，產(chǎn)生感應(yīng)電壓。電樞是旋轉(zhuǎn)磁場交流發(fā)電機的不動部分(定子)BaseLoadBaseloadisthatportionofabuildingloaddemandwhichisconstant.Itisthe"base"ofthebuildingdemandcurve.基本負(fù)荷基本負(fù)荷是指建筑負(fù)荷需求量中不變的那一部分，是構(gòu)成負(fù)荷需求曲線的基數(shù)。BlackStartBlackStartreferstothestartingofapowersystemwithitsownpowersources,withouttheassistancefromexternalpowersupplies.黑啟動黑啟動是指依靠系統(tǒng)內(nèi)部的電源，而不借助外部的電力進行的啟動。CT(CurrentTransformer)Currenttransformersareinstrumenttransformersusedinconjunctionwithammeters,controlcircuitsandprotectiverelaying.Theyusuallyhave5amperesecondaries.電流互感器電流互感器是一種儀表變壓器，通常與電流表、控制電路、保護繼電器配套使用。CircuitAcircuitisapathforanelectriccurrentacrossapotential(voltage).電路電路是電流通過電勢(電壓)的路徑CircuitBreakerAcircuitbreakerisaprotectivedevicethatautomaticallyinterruptsthecurrentflowingthroughitwhenthatcurrentexceedsacertainvalueforaspecifiedperiodoftime.SeeAirCircuitBreaker,MainBreaker,MoldedCaseCircuitBreakerandPowerCircuitBreaker斷路器線路斷路器是一個保護裝置，當(dāng)通過它的電流超過某個安全設(shè)定值一定時間后，它就能夠自動切斷電流。(見空氣線路斷路器、主開關(guān)、塑殼線路斷路器等)。CirculatingHarmonicCurrentsCirculatingHarmonicCurrentsarecurrentsthatflowbecauseofdifferencesinvoltagewaveformsbetweenparalleledpowersources,orinducedbyoperationofnon-linearloads.諧波環(huán)流諧波環(huán)流是由并聯(lián)電源間不同的電壓波形或者非線性負(fù)荷運轉(zhuǎn)而產(chǎn)生的電流。ContinuousLoadAcontinuousloadisaloadwherethemaximumcurrentisexpectedtocontinueforthreehoursormore(asdefinedbytheNECfordesigncalculations).持續(xù)負(fù)荷持續(xù)負(fù)荷是指使電流在3個小時或更長時間(根據(jù)NEC的定義)內(nèi)需保持最大值的負(fù)荷。CurrentCurrentistheflowofelectriccharge.Itsunitofmeasureistheampere.電流電流是電荷的流動，以安培為單位。CycleAcycleisonecompletereversalofanalternatingcurrentorvoltagefromzerotoapositivemaximumtozeroagainandthenfromzerotoanegativemaximumtozeroagain.Thenumberofcyclespersecondisthefrequency.周期周期是指交流電流或電壓從零到正最大值再到零，然后從零到負(fù)最大值再到零這樣一個往復(fù)的過程；而頻率則是指每秒可完成的周期數(shù)。DeltaConnectionDeltaconnectionreferstoathreephaseconnectioninwhichthestartofeachphaseisconnectedtotheendofthenextphase,formingthetriangle-shapedGreekletterDelta.Theloadlinesareconnectedtothecornersofthetriangle.三角形連接三角形連接是指在三相連接中，相臨兩相首尾相連，構(gòu)成三角形的希臘字母Delta,負(fù)荷線連接在三角形的角DifferentialRelayAdifferentialrelayisaprotectivedevicethatisfedbycurrenttransformerslocatedattwodifferentseriespointsintheelectricalsystem.Thedifferentialrelaycomparesthecurrentsandpicksupwhenthereisadifferenceinthetwo,whichsignifiesafaultinthezoneofprotection.Thesedevicesaretypicallyusedtoprotectwindingsingeneratorsortransformers.差動繼電器作為保護裝置，差動繼電器由位于系統(tǒng)中兩個不同位置的電流互感器提供反饋信息。差動繼電器對電流進行比較，如果存在不同則表示受保護區(qū)域內(nèi)有故障存在。這些裝置常被用于保護發(fā)電機或變壓器的線圈。DigitalMasterControl(DMC)Thisdeviceisdesignedtocontrolthepowersystemsinafacility.ItisofferedasanoptiononCumminsswitchgear.數(shù)字主控制器數(shù)字主控制器是用于控制設(shè)備電力系統(tǒng)的裝置。在康明斯開關(guān)柜中數(shù)字主控制器是選配件。DirectCurrent(DC)Directcurrentiscurrentwithnoreversalsinpolarity.直流直流是指沒有正負(fù)極性往復(fù)變化的電流。DroopLoadSharingDrooploadsharingisamethodofmakingtwoormoreparallelgeneratorsetsshareasystemkWload.Thisisaccomplishedbyhavingeachgovernorcontroladjustedsothatthesetshavethesamedroop(reductionofspeed).Typicaldroopistwocyclesinfrequencyfromnoloadtofullload.轉(zhuǎn)速降負(fù)荷分配轉(zhuǎn)速降負(fù)荷分配是兩臺或多臺機組負(fù)荷分配的一種方法。這通過每臺并聯(lián)機組調(diào)速器具備相同的轉(zhuǎn)速降。從空載到滿載轉(zhuǎn)速降一般為兩赫茲。Efficiency(EFF)Efficiencyistheratioofenergyoutputtoenergyinput,suchastheratiobetweentheelectricalenergyinputtoamotorandthemechanicalenergyoutputattheshaftofthemotor.效率效率是輸出能量與輸入能量的比率，例如輸入到電動機的電能與電機軸承輸出的機械能的之間的比率。EmergencySystemAnemergencysystemisindependentpowergenerationequipmentthatislegallyrequiredtofeedequipmentorsystemswhosefailuremaypresentalifesafetyhazardtopersonsorproperty.應(yīng)急系統(tǒng)應(yīng)急系統(tǒng)是指根據(jù)相關(guān)法規(guī)要求，為那些可能會危及生命安全或造成財產(chǎn)重大損失的設(shè)備或系統(tǒng)提供電源的獨立發(fā)電設(shè)備。EnergyEnergyismanifestinformssuchaselectricity,heat,lightandthecapacitytodowork.Itisconvertiblefromoneformtoanother,suchasinageneratorset,whichconvertsrotatingmechanicalenergyintoelectricalenergy.TypicalunitsofenergyarekW/h,Btu(Britishthermalunit),Hp/h,ft/lbf,jouleandcalorie.能量能量以電能、熱能、光能等形式存在，可以做功，也可以從一種形式轉(zhuǎn)換為另一種形式，例如發(fā)電機組能把機械能轉(zhuǎn)變?yōu)殡娔堋＝?jīng)常用的能量單位有：千瓦/小時、英國熱量單位、馬力/小時、焦耳、卡等。FaultAfaultisanyunintendedflowofcurrentoutsideitsintendedcircuitpathinanelectricalsystem.故障故障是指在電力系統(tǒng)中任何電流跑出正常電路以外的情況。FrequencyFrequencyisthenumberofcompletecyclesperunitoftimeofanyperiodicallyvaryingquantity,suchasalternatingvoltageorcurrent.Itisusuallyexpressedas(Hz)HertzorCPS(cyclespersecond).頻率頻率是指周期性變化的事物(如交流電壓和電流等)在單位時間內(nèi)完成的周期數(shù)，常用單位是赫茲(Hz)或周期/秒(CPS)。FrequencyAdjustPotentiometerAfrequencyadjustpotentiometerisusedtomanuallybringthefrequency(speed)oftheincomingsettothatofthebusforsynchronizingpurposes.Whenthegeneratorsetisparalleled,operationofthispotentiometerwilladjustthekWloadassumedbythegeneratorset.頻率調(diào)整電位器頻率調(diào)整電位器是用于手動調(diào)整輸入機組的頻率使之與母排同步。當(dāng)機組并聯(lián)后，電位器可以調(diào)整為機組輸出功率值。FrequencyRegulationFrequencyregulationisameasurethatstatesthedifferencebetweenno-loadandfull-loadfrequencyasapercentageoffull-loadfrequency.頻率調(diào)整率頻率調(diào)整率是指空載和滿載之間頻率的差別與滿載頻率的百分比。GeneratorAgeneratorisamachinewhichconvertsrotatingmechanicalenergyintoelectricalenergy.發(fā)電機發(fā)電機是把(旋轉(zhuǎn))機械能轉(zhuǎn)化為電能的裝置。GovernorAgovernorisadeviceontheenginewhichcontrolsfueltomaintainaconstantenginespeedundervariousloadconditions.Thegovernormusthaveprovisionforadjustingspeed(generatorfrequency)andspeeddroop(noloadtofullload).調(diào)速器調(diào)速器是安裝在發(fā)動機上的一個裝置，在不同的負(fù)載條件下通過控制燃料量來保持發(fā)動機的恒定轉(zhuǎn)速。調(diào)速器必須具備轉(zhuǎn)速調(diào)整(發(fā)電機頻率)和降速降調(diào)整(零負(fù)荷到滿負(fù)荷)功能。GridTheutility-ownedpowerdistributionsystem.電網(wǎng)電網(wǎng)是指電廠的電力輸送系統(tǒng)。GroundAgroundisaconnection,eitherintentionaloraccidental,betweenanelectricalcircuitandtheearthorsomeconductingbodyservinginplaceoftheearth.接地接地是電路與地面或地面上的導(dǎo)體的連接，可以是有意的也可以是意外的。GroundFaultProtectionThisfunctiontrips(opens)acircuitbreakerorsoundsanalarmintheeventthatthereisanelectricalfaultbetweenoneormoreofthephaseconductorsandground(earth).Thisgroundfaultprotectionfunctionmaybeincorporatedintoacircuitbreaker.接地故障保護當(dāng)一個或多個相導(dǎo)線與地之間出現(xiàn)電氣故障時，接地故障保護通過跳脫斷路器或報警來示警。這種功能可以一體化設(shè)計在斷路器上Hertz(Hz)ThetermHertzisthepreferreddesignationforcyclespersecond(CPS)andisusedtodescribefrequency.赫茲赫茲是頻率單位，也等于周期/秒(CPS)。HuntingHuntingisaphenomenonthatcanoccuruponloadchangesinwhichthefrequencyorthevoltagecontinuestoriseaboveandfallbelowthedesiredvaluewithoutreachingasteady-statevalue.Itiscausedbyinsufficientdamping.游車游車是一種在負(fù)載變化引起的頻率、電壓高于或低于期望值，無法達到穩(wěn)定的現(xiàn)象。它是由于阻尼不足而造成的。InsulationInsulationisnon-conductivematerialusedtopreventleakageofelectriccurrentfromaconductor.Thereareseveralclassesofinsulationinuseforgeneratorconstruction,eachrecognizedforamaximumcontinuous-dutytemperature.絕緣絕緣體就是非導(dǎo)電材料，用來防止導(dǎo)體中電流的泄露。按最高持續(xù)耐熱度劃分，發(fā)電設(shè)備中使用的絕緣體有多種等級。LaggingPowerFactorLaggingpowerfactorinACcircuits(apowerfactoroflessthan1.0)iscausedbyinductiveloads,suchasmotorsandtransformers,whichcausethecurrenttolagbehindthevoltage.SeePowerFactor.滯后功率因數(shù)交流電路中的滯后功率因數(shù)(小于1.0)是由感應(yīng)負(fù)荷引起的，例如發(fā)動機、變壓器，使電流滯后于電壓。(參照功率因數(shù))LeadingPowerFactorLeadingpowerfactorinACcircuits(0.0to-1.0)iscausedbycapacitiveloadsoroverexcitedsynchronousmotorswhichcausethecurrenttoleadthevoltage.SeePowerFactor.超前功率因數(shù)交流電路中的超前功率因數(shù)(0.0to-1.0)是由電容負(fù)荷或者過勵的同步電動機引起的，使電流超前于電壓。(參照功率因數(shù))Line-To-LineVoltageLine-to-linevoltageisthevoltagebetweenanytwophasesofanACgenerator.線電壓線電壓是指交流發(fā)電機任何兩相間的電壓。

Line-To-NeutralVoltage相電壓Ina3-phase,4-wire,Y-connectedgenerator,line-to-neutralvoltageisthevoltagebetweenaphaseandthcommonneutralwherethethreephasesaretiedtogether.在三相四線星形連接的發(fā)電機中，相電壓是指三相連接點與每相之間的電壓。LoadFactorTheloadfactoristheratiooftheaverageloadtothegeneratorsetpowerrating.負(fù)荷系數(shù)負(fù)荷系數(shù)指的是機組的平均負(fù)荷與額定功率之間的比率。LoadSheddingLoadsheddingistheprocessbywhichthetotalloadonaparallelingsystemisreduced,onoverloadofthsystembus,sothatthemostcriticalloadscontinuetobeprovidedwithreliableelectricalservice.卸載在超載的系統(tǒng)母排上，并聯(lián)系統(tǒng)的總負(fù)載被降低的過程稱為卸載，以確保最關(guān)鍵負(fù)載獲得可靠的電力供應(yīng)。LowVoltageACsystemoperatingvoltagesfrom120to600VAC.低壓交流電系統(tǒng)中從120到600VAC的電壓稱為低壓。返回MainBreaker主開關(guān)Amainbreakerisacircuitbreakerattheinputoroutputofthebus,throughwhichallofthebuspowermuMainBreaker主開關(guān)flow.Thegeneratormainbreakeristhedevice,usuallymountedonthegeneratorset,thatinterruptsthegenset'spoweroutput.Mainbreakersprovideovercurrentprotectionandasingledisconnectpointforallinaswitchboardordevice.主開關(guān)是在母排輸入或輸出端的線路斷路器，所有的電流都要從那通過。主開關(guān)通常安裝在發(fā)電機組上，用斷輸出電流。主開關(guān)能夠提供過電流保護，是配電盤或設(shè)備的電源斷開點。MainsMainsisatermusedextensivelyoutsideoftheUnitedStatestodescribethenormalpowerservice(utility市電市電是美國以外的區(qū)域?qū)ΤＲ?guī)電力服務(wù)的廣泛稱謂。MasterControlAcontrolsectioninatypicalparallelingsystemthatprovidestotalsystemmeteringandtheinterfacepointbetweentheparallelingsystemandthefacility.主控制主控制是典型的并聯(lián)系統(tǒng)計量控制設(shè)備，也是并聯(lián)系統(tǒng)與用電設(shè)施之間的接口。MediumVoltageACsystemoperatingvoltagesfrom601to15000VAC.

中壓交流電系統(tǒng)中從601到15000VAC的電壓稱為中壓。Modbus“專用名詞”AnindustrialnetworkingsystemthatusesRS-232serialmaster-slavecommunicationsatdatatransferratupto19.2KBPS.一種工業(yè)網(wǎng)絡(luò)，它使用RS232主從通訊模式傳輸數(shù)據(jù)，最快可達19.2kBPS。ModulesModulesarealsocallednodesordevices.ThesearedevicessuchasGensetCommunicationModules(GCMs),ControlCommunicationModules(CCMs),andDigitalInput/OutputModules(DIMs).模塊模塊也可以稱作接點或組件，例如機組通訊模塊(GCMs)、控制通訊模塊(CCMs)以及數(shù)字輸入/輸出模塊(DIMoldedCaseCircuitBreakerAmoldedcasecircuitbreakerautomaticallyinterruptsthecurrentflowingthroughitwhenthecurrentexcethetripratingofthebreaker.Moldedcasereferstotheuseofmoldedplasticasthemediumofelectricalinsulationforenclosingthemechanisms,andforseparatingconductingsurfacesfromoneanotherandfrogrounded(earthed)metalparts.Moldedcasecircuitbreakersusuallycontainthermal-magnetictripunits,althoughlargersizescanbeequippedwithsolidstatetripsensors.塑殼斷路器塑殼斷路器能夠自動切斷電流在電流超過跳脫設(shè)定后。塑殼指的是用塑料絕緣體來作為裝置的外殼，用來隔體之間以及接地金屬部分。塑殼斷路器通常含有熱磁跳脫單元，而大型號的塑殼斷路器會配備固態(tài)跳脫傳感返回NetworkAcollectionofNodesthatcommunicatewithoneanotheroveracommonmedium.網(wǎng)絡(luò)在共同的介質(zhì)上互相通訊的接點的集合就是網(wǎng)絡(luò)。NeutralCurrentNeutralcurrentisthecurrentthatflowsintheneutrallegofaparallelingsystem.Often,thistermisusedireferencetocirculatingcurrentsorcrosscurrents.零線電流零線電流指的是通過并聯(lián)系統(tǒng)零線的電流，在談及環(huán)流電流或者交叉電流時常會提到這個術(shù)語。NonlinearLoadAnonlinearloadisaloadforwhichtherelationshipbetweenvoltageandcurrentisnotalinearfunction.Scommonnonlinearloadsarefluorescentlighting,SCRmotorstartersandUPSsystems.Nonlinearloadscabnormalconductorheatingandvoltagedistortion.非線性負(fù)載電壓和電流之間是非線性關(guān)系的負(fù)載稱為非性形負(fù)載。一些常見的非線性負(fù)載有熒光燈、可控硅電動機啟動及UPS系統(tǒng)。非線性負(fù)載能導(dǎo)致反常的導(dǎo)體發(fā)熱和電壓畸變。返回

0OhmTheohmisaunitofelectricalresistance.Onevoltwillcauseacurrentofoneamperetoflowthrougharesistanceofoneohm.歐姆歐姆是電阻單位。1伏特的電壓通過1歐姆的電阻能產(chǎn)生1安培的電流。One-LineDiagramAone-linediagramisaschematicdiagramofathree-phasepowerdistributionsystemwhichusesonelinshowallthreephases.Itisunderstoodwhenusingthiseasytoreaddrawingthatonelinerepresentsthre單線圖單線圖是用一條線來表示三相電力分布系統(tǒng)的示意。，OvercrankOvercrankisanalarmfunctionprovidedwithmostgeneratorsetsthatindicatethatthegeneratorsethastostart.盤車失敗盤車失敗是機組的預(yù)警功能，表示發(fā)電機組啟動失敗，大多數(shù)機組都有這種功能。返回pParallelingBreakerAparallelingbreakeristhecircuitbreakerthatconnectsthegeneratorsettotheemergencybus,andacrowhichalltheindividualgeneratorsynchronizingfunctionsoccur.并聯(lián)開關(guān)并聯(lián)開關(guān)是連接發(fā)電機組和應(yīng)急母排的線路斷路器，所有的單個發(fā)電機通過它完成同步運行。ParallelingControlAparallelingcontrolcontainstheelectricalequipmentprovidedinaparallelingsystemforcontrolofasing并聯(lián)控制generatorset.并聯(lián)控制是并聯(lián)系統(tǒng)中用來控制單個發(fā)電機組的電氣設(shè)備。PhaseAnglePhaseanglereferstotherelationbetweentwosinewaveswhichdonotpassthroughzeroatthesametimConsideringonefullcycletobe360degrees,thephaseangleexpresseshowfarapartthetwowavesarerelationtoeachotherindegrees.相角相角指的是兩個不同時經(jīng)過零點的正弦波之間的關(guān)系。一個完整周期為360度，相角就是用度數(shù)來表示兩個距離。PhaseRotationPhaserotation(orphasesequence)describestheorder(A-B-C,R-S-T,orU-V-W)ofthephasevoltagesaoutputterminalsofathree-phasegenerator.Thegeneratorphaserotationmustmatchthefacilityphaserotation.Thismustbecheckedpriortooperationoftheelectricalloadsinafacilitywithanon-sitegenerat相序相序表示的是三相發(fā)電機輸出終端相電壓的順序。在用電負(fù)載運轉(zhuǎn)之前必須檢查確保發(fā)電機的相序與用電設(shè)相序一致。

PortTheexternalconnectoronadeviceatwhichthenetworkcableormediumisattached.接口設(shè)備的外接口，用于連接網(wǎng)絡(luò)線或者其它介質(zhì)。PowerFactorPowerfactoristhecosineoftheanglebetweentheactivepower(kW)andapparentpower(kVA功率因數(shù)功率因數(shù)是電路中有功功率(kW)和視在功率(kVA)之間夾角的余弦值。PrimePowerPrimePowerdescribesanapplicationwherethegeneratorset(s)mustsupplypoweronacontinandforlongperiodsoftimebetweenshutdowns.Noutilityserviceispresentintypicalprimapplications.常載常載是指發(fā)電機組可長時間和連續(xù)的運行。通常在沒有市電供應(yīng)，發(fā)電機組作為首要電源的場合使用。PriorityControlPrioritycontrolistheprocessbywhichthetotalloadsonthebusislimitedtothemostcrsystemuntiladequategenerationcapacityisavailabletoserveallloads.優(yōu)先級控制優(yōu)先級控制是指當(dāng)總負(fù)載電力需求大于發(fā)電機組的輸出時，首先要滿足最關(guān)鍵負(fù)載的電力需求。ProtocolAsetofrulesusedmutuallybytwoormoredevicestocommunicate.Also,knownasthe"langunetwork.協(xié)議兩個或多個設(shè)施共同遵守的一些通訊規(guī)則，在網(wǎng)絡(luò)中常稱為“語言”。返回RRadioInterferenceRadiointerferencereferstotheinterferencewithradioreceptioncausedbyageneratorset.無線電干擾無線電干擾是指發(fā)電機組對無線電信號接收造成的干擾。ReactivePowerReactivepowerispowerthatflowsbackandforthbetweentheinductivewindingsofthegenerinductivewindingsofmotors,transformers,etc.,whicharepartoftheelectricalload.Thisworkintheelectricalloadnordoesitpresentloadtotheengine.Itdoesapplyloadtothethecapacityofthegenerator.無功功率無功功率是指電流在發(fā)電機、電動機、變壓器等的感應(yīng)線圈之間往復(fù)流動，這也構(gòu)成了電力負(fù)載的一部分。沒做有用功，而且也不是發(fā)動機的負(fù)載，但是作為發(fā)電機負(fù)載，限制了發(fā)電機的容量。ReversePowerAreversepowerrelayisarelaywithawattmetermovementthatsensesthedirectionofpowerRelayparalleledsets,aflowofreversepower(i.e.,powerflowintoset)willactuatethereversedisconnectthesetfromthesystem.Ifonesetstopsandreversepowerprotectionisnotprovrunningwilldrivethesetthathasstopped.Thegeneratoronthesetthathasstoppedwilla逆功率繼電器逆功率繼電器是指帶瓦特計的繼電器，用來感知電流的方向。在并聯(lián)機組中，反方向電流(例如流回發(fā)電機

電流）會啟動逆功率繼電器，把該機組與系統(tǒng)斷開。如果一臺發(fā)電機組沒有運轉(zhuǎn)，并且沒有逆功率繼電器保運轉(zhuǎn)的機組就會驅(qū)動這個機組，這臺機組上的發(fā)電機則變成電動機運行。返回sSCRSiliconControlledRectifier--athree-electrodesolid-statedevicewhichpermitscurrenttoflowinonedireconly,anddoesthisonlywhenasuitablepotentialisappliedtothethirdelectrode,calledthegate.可控硅整流器可控硅整流器——三電極固態(tài)元件，只有當(dāng)匹配的電壓作用于第三電極（選通電極）時，才能夠保證電流朝方向流動。ShortCircuitAshortcircuitisgenerallyanunintendedelectricalconnectionbetweencurrentcarryingparts.短路短路通常是指帶電流的組件之間意外的電路連接。ShuntTripShunttripisafeatureaddedtoacircuitbreakerorfusibleswitchtopermittheremoteopeningofthebreaswitchbyanelectricalsignal.分勵脫扣分勵脫扣是線路斷路器或可熔電閘的一個特性，可通過遠(yuǎn)程信號來進行分?jǐn)嗷蜣D(zhuǎn)換。SoftLoadingSoftloadingreferstotherampingofloadontooroffofageneratorinagradualfashionforthepurposeofminimizingvoltageandfrequencytransientsonthesystem.軟加載軟加載是指在給發(fā)電機組增加或減少負(fù)載時要逐漸進行，以減少電壓和頻率對系統(tǒng)的瞬變影響。SoundLevelMeterAsoundlevelmetermeasuressoundpressurelevel.Ithasseveralfrequency-weighteddecibel(dB)scale聲級表B,C)tocoverdifferentportionsoftherangeofmeasuredloudness.SoundlevelmetersindicateRMSsouunlessthemeasurementsarequalifiedasinstantaneousorpeaksoundlevel.聲級表是用來測量聲壓級別的，它根據(jù)聲音的頻率分為幾個分貝級(A,B,C)。聲級表表征的是均方根聲音非是適合瞬間或峰值的度量。SoundPressureLevel(SPL)Soundpressurelevelisameasurementofthepressurefluctuationsofasoundwaveasitpropagatesthrotheair.Becauseofthewiderangeofpressurestowhichtheearresponds,alogarithmicscaleisusedandexpressedasaratioofthemeasuredpressurereferencedtoapressureof2x10-5N/m2(20mPa)whichthresholdofhumanhearingat1000Hz.Themeasureisexpressedindecibels(dB).TheBelunitisnameafterAlexanderGrahamBell.聲壓級別聲壓級別是表示在空氣中傳播的聲波的起伏壓。由于耳朵能感知的聲壓范圍很大，所以采用其對數(shù)值，并以2xN/m2（20mPa）的比率表示，這是人類在1000Hz所能聽到的極限，單位是分貝（dB）。貝爾（十分貝）是以山大?格雷姆?貝爾的名字命名的。StandbySystemAstandbysystemisanindependentpowersystemthatallowsoperationofafacilityintheeventofnorma

powerfailure.備用系統(tǒng)備用系統(tǒng)是一個獨立的電力供應(yīng)系統(tǒng)，當(dāng)常規(guī)電力供應(yīng)失敗時，備用系統(tǒng)就會運行。StarConnectionSeeWyeConnection.星形連接參見Y形連接。StartingCurrent啟動電流Theinitialvalueofcurrentdrawnbyamotorwhenitisstartedfromstandstill.當(dāng)發(fā)動機從停止?fàn)顟B(tài)啟動時帶來的初始電流值就是啟動電流。SurgeSurgeisthesuddenriseinvoltageinasystem,usuallycausedbyloaddisconnect.突變突變是指系統(tǒng)中電壓突然升高，通常是由于負(fù)載斷開而引起的。SyncCheckRelayAsynccheckrelayisanelectricaldevicethatmonitorsthephaserelationshipbetweentwovoltagesourceandprovidesasignalwhenthevoltagesourcesarewithinspecificpresetparameters.同步檢查繼電器同步檢查繼電器是監(jiān)測兩個電壓源之間的相位關(guān)系的電氣設(shè)備，如果電壓源間的關(guān)系在預(yù)定的參數(shù)范圍內(nèi)，會發(fā)出相應(yīng)信號。SynchronizerAsynchronizerisanelectronicdevicethatmonitorsthephaserelationshipbetweentwovoltagesourcesaprovidesaconnectionsignaltoanenginegovernor,toforcethegeneratorsettosynchronizetothesystebus.同步器同步器是用來監(jiān)測兩個電壓源之間的相位關(guān)系的電子設(shè)備，它向發(fā)動機調(diào)速器發(fā)出信號，以促使發(fā)電機組與母排能夠同步。SynchronousGeneratorAsynchronousgeneratorisanACgeneratorhavingaDCexciter.Synchronousgeneratorsareusedasstand-alonegeneratorsforemergencypowerandcanalsobeparalleledwithothersynchronousgeneratoandtheutilitysystem.同步發(fā)電機同步發(fā)動機是配有直流勵磁機的同步交流發(fā)電機。同步發(fā)動機能作為獨立的緊急電源，也可以與其他同步發(fā)或市電并聯(lián)。返回TransferSwitchAtransferswitchisanelectricaldeviceforswitchingloadsbetweenalternatepowersources.Anautomatitransferswitchmonitorstheconditionofthesourcesandconnectstheloadtothealternatesourceifthepreferredsourcefails.轉(zhuǎn)換開關(guān)轉(zhuǎn)換開關(guān)是能夠把負(fù)載在備用電源和常規(guī)電源之間進行轉(zhuǎn)換的電氣設(shè)施。自動轉(zhuǎn)換開關(guān)能夠進行監(jiān)控，如果電源供應(yīng)失敗，就自動把負(fù)載連接到備用電源。

Utility市電VoltageDipUtility市電VoltageDip電壓暫降VoltageRegulation電壓調(diào)整率Watt-HourMeter電度表WyeConnectionsY連接市電是商業(yè)電源，從大型中央電站向各設(shè)施供電。返回Voltagedipisthedipinvoltagethatresultswhenaloadisadded,occurringbeforetheregulatorcancorreorresultingfromthefunctioningofthevoltageregulatortounloadanoverloadedengine-generator.電壓暫降是在負(fù)荷增加而調(diào)整器還未能進行校正時、或電壓調(diào)整器正在為過載的發(fā)動機卸載時出現(xiàn)的電壓下返回Voltageregulationisameasurethatst