西门子变频器手册-technical terms for standard

TechnicalTermsforStandardHowdoesadriveAdriveisanelectronicdevicetocontrolthespeedofelectricmotors.Itbasicallyconsistsofthreeparts:arectifierunit,aDClinkconnectionandaninverterunit.Therectifierunittransformsthe ingalternatingcurrent(AC)fromthepowersupplyintodirectcurrent(DC).ThisdirectcurrenthasstrongvoltageripplesandissmoothenedoutbytheDClinkconnection.Theresultingdirectcurrentisthentransformedbytheinverterunitintoathree-phasealternatingcurrent(3AC).Theresultingcurrentisproducedbyswitchingonandoffs(InsulatedGateBipolarTransistors)atanadjustablefrequency(2kHz-16kHz)–theswitchingfrequency.Thistechniqueiscalled‘PulseWidthModulation’( Theresulting3-phase currentisfinallyfedintothemotor.Usingthismodulationtechniqueonecancontroltheoutputvoltageandtheoutputfrequency–thoseparameters,whicharefinallyresponsibleforthespeedofthemotor.+CC- DC VoltageSchematicVoltagePulseWidthWhousesDrivescangenerallybeusedwhereverthereisanelectricmotor.Becauseofthehighlifespanandveryreliableoperation,ACmotorsgraduallysupersedeDCmotorsthusincreasingthedemandforACdrives.DCdrivesaretechnicallyspeakingaloteasiertorealize,butthecorrespondingmotorsareonthedeclineduetofactorssuchasmaintenancetimespansandreplacementofabrasedparts.OEMs(OriginalEquipmentManufacturers)producemachinesthatinturnarefortheproductionofgoods.Astheneedforabetterproductqualitysteadilyincreases,productionprocesseshaveto emoreeffective,reliableandprecise.Whereinthepastitwassufficientforamotortoturnatjustonespeed,itisnowrequiredtoadjusttomorecomplexrequirements–uptothelevelofafullyautomatedproductionline.Insimplecasesmotorspeedsareselectedmanuallyviasomecontrolpanels.Ontheotherhandinamoresophisticatedenvironment,theseparametersareadjustedautomaticallyviafullylinkedautomationnetworkswhereadrivefulfilsthemost ksattheveryendoftheautomationhirarchy.Thus,drivesarevirtuallyeverywhere–controllingconveyorbelts,elevators,pumps,fans,spinners,winders,cranes,hoists,centrifuges,positioningdevices,extruders,washingmachines,orevenautomaticjoggingmachinesathome.Someofthemostrelevantindustrialbranchesareforexampleprinting,textile,packaging/labelling,food/beverage,heatingandventilation,plasticproduction,pulp&p r,elevators,waterandsewagesystems,ceramicsprocessing,chemicalindustryetc..ogueInput模拟输入Theogueinputisusedtosteplesslycontrolthespeedofthedrive,e.g.bymeansofapotentiometer.Thespeedisthusdependentonthevoltageorcurrent(configurable)appliedtotheogueinputterminal.ogueOutput模拟输出Theogueoutputenablestheusertomonitorcertainparametersofthedrivebyadjustingthe ogueoutputcurrent.Itcanbeconfiguredtomonitor:OutputFrequencyMotorDC-linkMotorMotorBoostModes(提升方式Atlowoutputfrequenciestheoutputvoltagenormallyislowtokeepthefluxlevelconstant.However,thevoltagemaybetoolowto elossesinthesystem.Thevoltagecanbeincreasedbyaddingso-called‘boost’.

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AdditionalvoltageBoostatlowFrequencyStartingboostduringrampStartingboostwillonlyproduceboostduringramuntilthesetpointisreached,andisthereforeusefulforadditionaltorqueduringstarting.Continousboostisoperationalallthetimeandcanintheworstcaseleadtoanovercurrenttripottooverheatingofthemotor.Boosthasnoeffectduringvectoroperationbecauseinthismodetheinvertercontinuouslycalculatestheoptimumoperatingconditions.BrakingMethods制动方式Insomeapplicationsitisnecessarytoquicklystopthemotor–forexampleinanemergencysituation.Insuchacaseonehastothinkaboutwhattodowiththeenergypresentinthemotor.Ifthepowersupplyiscutoffabruptlythemotoractsasageneratorandthedirectionoftheelectriccurrentisreversed.Thus,insteadoftransportingenergyfromtheinvertertothemotor,theflowisreversedandcaneventuallydestroytheinverter.Togetaroundthisproblem,onecanuseseveralBrakingchopper(forMMV):theenergyisdissipatedinanexternalresistorthatcanbeinstalledalongsidetheinverter.ItisspeciallydesignedtooperatewiththehighvoltagespresentintheDClink.ExternalBreakingUnit(EBU):requiredforMidimaster,togetherwithanexternalresistor.AnEBUneedsaseparatepowersupplyandoperateswiththeDClinkoftheinverter.DCinjectionbraking:aDCcurrentisinjectedintothemotorwindingswhichdissipatestheenergyinsidethemotorWhereasapproaches1.)and2.)requiresomeextraequipment,approach3.)isaninternalfeatureofinverters.SimpleDCinjectionbrakinghoweverisdifficulttocontrolandcancausesomeunpredictabletorquebehaviourduringthebrakingprocess.Thereforeanimprovedversioncalled‘CompundBraking’wasdevelopped,whichinjectstheDCcurrentintothewindingsinacontrolledfashionandminimisesregenerationtotheinverter.DigitalInputs数字输入Thepurposeofthedigitalinputsistocommunicatewiththeenvironmentandtoenabletheusertoadjusttheinvertertohisneeds.InthecaseoftheMicromasterthedigitalinputsareprogrammableandcansobeusedtoservedifferentpurposes.Themostimportantamongthemare:SetthemotorspeedtofixedReversetheJogEnableDCDisableprogrammingEMCfeatures电磁兼容EMCstandsforelectromagneticcompatibility.Everyelectricdeviceproducessomekindofelectromagneticradiation.InvertersareamongtheheavyproducersofthiskindofradiationandEMCfeaturesneedtobeconsideredtoguaranteestableoperation.Hereisanoverwievofthetypicalradiationsourcesinsideaninverter:Inverter:Inverter:3kHz-+CCRectifier100Hz-ControlUnit30Mhz-RadiationsourcesinsideaEspeciallyfornon-groundedequipmenectromagneticdisturbancescanseriouslydisrupttheoperationofsensitiveelectronicparts.Thesedisturbancesaretothegreatesparttransmittedthroughwiresandtoalesserdegreebyradiation.Toavoidthis,EMCfiltersshouldbeinstalledtomakedrivescompatiblewithotherelectricequipment.OurMicromastercanbedeliveredwithEMCfiltersforvariousdemands.EnergyControlOptimizationECOonly带能程序Ifthisfunctionisswitchedon,theECOsearchesforthebestoperatingpointafterreachingthesetpointbyincreasinganddecreasingthemotorvoltageuntilminimumpowerconsumptionisachieved.Theamountofadditionalenergysavedusingthisoptimizationtechniquecanvaryconsiderablyandisdependentonmotorloading,motortypeanddutycycle.Typicaladditionalsavingscanbebewteen2%and5%. optimumoperatingEnergyControlOptimizationFCCcontrol(磁通电流控制Toimprovemotorefficiencyandtorqueresponsehasdevelopedanimprovedcurrentmonitoringsystemwhichallowsaccuratemeasurementoftheoutputcurrentwithreferencetothemotorvoltagethroughreal-timecalculations.Thisnumericalsimulationofthemotorbehaviourenablesthemonitoringsystemtoseparatethetotaloutputcurrentintothereal(load)andimaginary(flux)part.However,thismethodisnotaseffectiveasfullvectorcontrolorsensorlessvectorFixedFrequencies固定频率FixedForagreaterflexibilityregardingtheselectionoftheinverter’sspeedstheMicromasterhas7fixedfrequencieswhichenabletheusertoeasilyconfigurethedrivetohisapplication.ThesefixedfrequenciescanbefreelyprogrammedandcanFixedPossiblecontrolcycleusingfixed

OpenCollectorOpencollectoroutputsservetocontrolcertainparametersofthedrive.Theycanbeconfiguredtoswitchonaandoffalow-voltagesignalswhichcanbetappedatsometerminals.Unlikerelayoutputsopencollectoroutputsarenotdesignedtoswitchelectricloadsdirectly.Todothissomeextraswitchingdeviceshavetobeused.However,opencollectoroutputsareusefultomonitorcertainparametersofthedrivesuchasattainmentofthefrequency,alarmstates,statusofthefanetc..OverloadCapabilitiesandProtectionSystems过载能力与附加保护ToprotectthedrivefromoverloadsandhighcurrentsMicromastermakesuseofseveralprotectionmechanisms.Theyrangefromveryfastemergencytripstoderatingmechanismstoprotectagainstdamagebyovervoltage,overcurrentandoverheating.ElectronicTrip.Thisisaveryfastcurrentlimitwhichoperatesifthereisashortcircuit(linetolineorlinetoearth)ontheoutput.Itisafixedleveltripandoperateswithinafewmicroseconds.OverloadLimit.Thisisafastprogrammablelimitandmaybeashighas200%ofthenominalcurrentlevel.LongtermOverloadlimit.Thisisaslowerlimit, whichallowsanoverloadofatleast60secondswhenthecurrentliesbetweentwoprogrammableparameters.Theactualtimeisdependentontheamountofoverload,butisatleast60seconds.Afterthistime,theoutputfrequencyisreduceduntilthenominallevelisreached.ContinuousLimit.Thisisthenominallevelwhichisalsoprogrammable.Theinverterwillcontrolthecurrenttothislevelaftertheoverloadsdescribedabovehavetimedout.Inalloftheabovecasesexceptfortheelectronictrip,theinverterwillreducetheoutputfrequencyinordertoreducetheload.OutputInstantaneousNominalCurrentOverloadadjustable,Max.150%NominalCurrentCurrent100%60s,

OutputcurrentoverloadPIDcontrol(比例，积分，微分增益PIDstandsforProportional,Integral,Derivativecontrolandisaregulationtechniquebasedonfeedbackloops.ThepurposeofthismechanismistokeepacertainparameterYconstant.Imagineforexampleanapplicationwhereadrivecontrolsapump,whichhastosustainaconstantpressureof500mbar.ThusyouhaveadesiredparametervalueofX=500mbar.TherealpumpressureYwillvaryduetomanyexternalfactorsandthereneedstobeafeedbackfromapressuresensorbacktothePIDinputterminal.ThePIDalgorithmsinsidethedrivecomparetherealpressurevalueYwiththesetpointXandadjustthespeedofthedrivesothatroughlyX=Ywillberealized.IfyouareinterestedinmoredetailsorwanttoknowexactlyhowthePIDalgorithmworks,youmightwanttohavealookat.SpeedSpeedACSpeedController(slow PressurePowerSupplyDisturbance供电波动Inafactoryenvironmenttheinverterunitisnottheonlyelectricconsumer.Otherunits(esp.heaters,welders,largedrivesorlightningsystems)mightuselargeamountsofenergycausingthefollowingproblems:thepowersupplymaycontainharmonicfrequencieswhichinturnleadstohighlossesintransformersandcaninterferewithsomeelectronicelementsthevoltagemaydropbelowthetoleratedlevelwhichcausestheinvertertovoltagepeakscanoccurwhichcandestroyelectronica3ACpowersupplycan eunsymmetricalandcausecompensationorleakagecurrentGenerallyspeakingtheseproblemsareaquestionoftolerances.Micromasterallowsinputtoleranceswithregardtovoltageandinputfrequencyandcancopewiththecommonfluctuations.However,indifficultcasesadditionalprotectionequipmentsuchasovervoltageprotectionorinputchokesisavailable.RelayOutput(断电器输出Relayoutputsareprogrammableterminalswhichcanswitchonoroffsomeelectricload,e.g.inanemergencysituationtoprotectthemotor.TheMicromasterrelayouputcanbetriggeredbythefollowingevents:InverterisDirectionoftheExternalbrakeInverterfrequencylessorequaltominimumFaultInverterfrequencygreaterthanorequaltoWarningOutputcurrentgreaterthanorequaltoadefinablecurrentMotorcurrentlimitMotorovertemperatureClosedloopmotorlow/highspeedSerialInterface直接接口Settingallofthedrive’sparametersmanuallybyflipthrougheachcanbeanardoustask.Tosimplifythisprocessaserialinterface(RS485)allowstheseparameterstobesetremo yviasomenetwork.OurdrivescommunicateviaaUSSprotocolwhichallowsupto30drivestobeconnectedandparticipateintheTotallyIntegratedAutomationNetwork.AsanoptiontheRS485interfacecanbetransformedintoaProfibusinterfacewhichprovidessomeextrafeaturesforenhancednetworkperformance.Slip/Slipcompensation(滑差、滑差补偿Thisfieldcrossestheairgapbetweenthestatorandrotorandcausescurrentstoflowintherotorwindings.Thisproducesaforceontherotorasthecurrentinteractswiththechangingmagneticfield,andtherotorturns.However,iftherotorrunsatthesamespeedastherotatingfield,therewillbenochangingmagneticfield,andthereforenotorque.Thereforetherotoralwaysrunsalittleslowerthantherotatingfieldinordertogeneratetorque.Thisdifferenceinspeedisknownasslip.Astheloadincreasesthemotorslowsdownalittleandtheslipincreases.Iftheloadistoogreatthemotorwillexceedtheumtorqueandstallor‘pullout’.Inordertocompensatethiseffectourinvertersprovideafeaturecalled‘slipcompensation’whichincreasestheoutputfrequencyslightlyastheloadincreases.Thisisrealisedbymeasuringtheoutputcurrent.Slipcompensationisnotoperationalwhenvectorcontrolisswitchedon,ascompensationisinherent.LoadLoad

EffectofloadchangeonThisfeatureallowsthemotortoaccelerateanddecceleratesmoothly.Withoutthisoptionthemotorstartsandstopsabruptlyandcancausesomemechanicalshock.Thisinturnmightdamagemechanicallysensitivematerialsuchasglassbottlesonaconveyorbelt. withNormalSmoothingappliedtoupanddown

Switchingfrequency脉冲频率TheinverterunitofthedriveconvertstheDCcurrentfromtherectifierunitintoathree-phaseACcurrentbymeansofpulsewidthmodulation.Thisthree-phasecurrentconsistsofshortpulseswhosewidthsaredefinedbytheswitchingfrequency.Switchingfrequenciesvaryfromaround2kHztoaround16kHz.Generallyonecansaythatlowerswitchingfrequenciescausegreatermotornoiseandlessheatproductioninthedrive,whereasthehigherswitchingfrequenciescauseanincreasedheatproductioninthedriveandasmoothandsilentrunningofthemotor.(Atlowspeedsaself-cooledmotorproducesmoreheatthanduringordinaryoperation,becauseheatdissipationisimpededbythereducedcoolingeffectoftheshaftmountedcoolingfan.ThereforetoprotectthemotoraspecialderatingalgorithmatlowspeedsviaaI2tmotorderatingcurvecan eimportant.Micromasterprovidesthreedifferentderatingcurves,whichcanbeselectedaccordingtotheheatproductionofindividualmotors.Shouldahighersafetystandardberequired,MicromasterprovidesaPTC(PositiveTemperatureCoefficient)inputforanthermalresistorwhichisinstalledatthemotoritselfandmonitorsitsactualNominal

derating BaseI2tMotorProtection(Initssimplestcontrolmode,Micromasterallowstheusertomanuallyadjusttherelationshipbetweenthespeed(f=frequency)ofthemotorandth