DC驱动基本知识

©ABBAPR/AWV-1DCS800DCDrivebasicsDC驱动基础DCS800ThomasVinzDCS800builtonDCStechnology©ABBAPR/AWV-2DCS800DCDrivebasicsDCDrivesbasics-Generallayout~~PLCMMI/PanelSpeedfeedbackLoadMV进线MV/LV变压器励磁变压器励磁熔断器励磁接触器励磁变流器励磁绕组AC-断路器半导体熔断器进线电抗器电枢变流器DC熔断器DC电机©ABBAPR/AWV-3DCS800DCDrivebasics电路原理图:电机变流器=IdUdiαcosMDCDrivesbasics-Armatureconverter3AC电网进线电抗器DC电压DC电流AC进线电流Usupply6-pulsethyristorbridge(linecommutated)可控电压源(触发角)Outputvoltagecanbepositiveornegative电压源特性:Udiα=90°135462EMKUdiαIdiLUL~~~Udiαcos©ABBAPR/AWV-4DCS800DCDrivebasicsTheconventionforaCartesiancoordinatesystemis:(该公约为一个笛卡尔坐标系统)The1stquadrantisonthetopright(第一象限最上面的是正确的)Allothernumbersfollowcounterclockwise(所有其他数据按照逆时针方向):ThusfollowsIIIIIIIVYXDCDrivesbasics–Quadrants(直流驱动器基础——象限)QuadrantIIIIIIIVx-coordinate0000y-coordinate0000©ABBAPR/AWV-5DCS800DCDrivebasicsIIActivebrakingIDrivingIIIDrivingIVBrakingSpeed(voltage)Torque(current)Typicalapplications:ExtruderMixerRodandbarmillsMUDIDDCDrivesbasics-Singlebridge(2-Q)Speedinonedirectiononly,oppositespeeddirectionisnotpossible!Negativecurrentisnotpossible!Activebrakingisnotpossible!©ABBAPR/AWV-6DCS800DCDrivebasicsDCDrivesbasics-Doublebridge(4-Q)IIActivebrakingIDrivingIIIDrivingIVBrakingSpeed(voltage)Torque(current)Typicalapplications:SkiliftsTestrigsForsmoothandfasttorquereversalMUDIDSpeedinbothdirectionsispossible!Negativecurrentispossible!Activebrakingispossible!©ABBAPR/AWV-7DCS800DCDrivebasicsDCDrivesbasics-Exampledoublebridge(4-Q)Torque(current)Speed(voltage)73465Motoracceleratingfromzerospeedtomaximumspeedandthenreversingtomaximumnegativespeedt2tSpeed(EMF)Torque(current)12345671©ABBAPR/AWV-8DCS800DCDrivebasicsTypicalapplications:MixerSlowchangeoveroftorqueLesscontrolperformanceP500KWMUDIDDCDrivesbasics-Singlebridge(2-Q)withfieldreversalIIActivebrakingIDrivingIIIDrivingIVBrakingSpeedTorque©ABBAPR/AWV-9DCS800DCDrivebasicsDCDrivesbasics-FieldreversalandoptitorquenrefNactTref-10%-100%10%Ia10%100%10%If100%-100%UaFieldreversal©ABBAPR/AWV-10DCS800DCDrivebasicsDCDrivesbasics-FieldreversalandoptitorqueOptitorque:Onlypossiblewithspeedfeedback(tachometer,encoder)nrefNactTref-10%-100%10%Ia10%100%10%If30%-100%-10%Ua30%30%©ABBAPR/AWV-11DCS800DCDrivebasicsDCDrivesbasics-FieldforcingFieldforcingisawaytoincreasethespeedoffieldcurrentchange.Thisispossibleby:Usingafullycontrolledfieldexciter,becauseitisabletogeneratenegativevoltage(ahalfcontrolledfieldexciterisnotabletodothat)UsinghigherACvoltages(thedisadvantageisahighervoltagerippleofthefieldvoltagewithalesssmoothcommutation)©ABBAPR/AWV-12DCS800DCDrivebasicsLimits:150°becauseofcommutation(current)andrecovery(thyristor)15°becauseofsafety,duetosupplyvoltagejitter0.9safetyfactorfor10%supplyvoltagedropIncaseofadditionalinternalvoltagedrops(e.g.linereactors)lowerthesafetyfactor(e.g.to0.89)DCDrivesbasics-MotorvoltageFora4-Qdriveor2-Qdrivewithfieldreversalisvalid:Uid=0.9*1.35*Usupply*cos150°e.g.:Usupply=400VACUid=420VDCFora2-Qdriveisvalid:Uid=0.9*1.35*Usupply*cos15°e.g.:Usupply=400VACUid=470VDC©ABBAPR/AWV-13DCS800DCDrivebasicsE.g.ABBDCmotorsareratedwithcontinuouscurrent.Inadditiontheycantakeancyclicoverloadof180%for20severy30minutesTheconverterhastobedimensionedaccordingtothe“real”load(current)oftheapplicationnotaccordingtotheratedcurrentofthemotornotaccordingtothemaximumcurrentofthemotorThisisdonebymeansofcustomizeddutycyclesusingDriveSizeDCDrivesbasics-Convertercurrent©ABBAPR/AWV-14DCS800DCDrivebasicsDCDrivesbasics-Standarddutycycles©ABBAPR/AWV-15DCS800DCDrivebasicsWhylinereactors?Fordi/dtlimitationduringcommutationTopreventinterferencesbetweenconvertersconnectedtothesamelineTopreventinterferencewithotherupstreamconnectedequipmentWhenthyristorconvertersoperate,thelinevoltageisshort-circuitedduringcommutationfromonethyristortothenext.Linereactorsareusedtoreducethecommutationspikesontheupstreamsupply.DCDrivesbasics-Linereactors~~LoadDisadvantage:ReductionofmaximumavailableDCvoltage,duetoitsvoltagedrop©ABBAPR/AWV-16DCS800DCDrivebasicsMMuk=1%or4%Line:OnelinereactorperdriveAutotransformer:RequiresanadditionallinereactorMuk=1%or4%Dedicatedtransformer:OnlyonetransformerperdriveTypicallyforhighpowerdrivesuk=1…10%MD7converters:MaximumtwoconverterspertransformerDCDrivesbasics-LinereactorsConfigurations:MMuk=1…10%Aux.voltage©ABBAPR/AWV-17DCS800DCDrivebasicsMMDCDrivesbasics-FusingofDCDrivesFailurescenarios:Faultintheelectronics,application,semiconductorsWrongtuningofcontrollersWrongparametersettingsDefectivePrintedCircuitBoards(ageing)Defectivesemiconductor(ageing)CommutationfailureMissinglinevoltageInsulationfailuresConverterWiringMotorACsupply©ABBAPR/AWV-18DCS800DCDrivebasicsDCDrivesbasics-FusingofDCDrivesFusesprotectagainst:ExplosionofsemiconductorswiththeriskoffireDamagesofthemotor(flashover)DamagesofsemiconductorsintheconverterProtectionphilosophy:Sizeofthesystem(costofinvestment)Application(2-Q,4-Q,mainlyregenerative)Acceptabledowntime,availabilityofsystemRiskthecustomerwantstotakeSupplyvoltageconditions(stablenet