怎么洗保暖内衣

怎么洗保暖内衣©UNEP2006TrainingAgenda:ElectricMotorsIntroductionTypesofelectricmotorsAssessmentofelectricmotorsEnergyefficiencyopportunitiesElectricalEquipment/ElectricMotors2©UNEP2006IntroductionElectromechanicaldevicethatconvertselectricalenergytomechanicalenergyMechanicalenergyusedtoe.g.Rotatepumpimpeller,fan,blowerDrivecompressorsLiftmaterialsMotorsinindustry:70%ofelectricalloadWhatisanElectricMotor?ElectricalEquipment/ElectricMotors3©UNEP2006IntroductionHowDoesanElectricMotorWork?ElectricalEquipment/ElectricMotors(Nave,2005)12344©UNEP2006IntroductionThreetypesofMotorLoadElectricalEquipment/ElectricMotorsMotorloadsDescriptionExamplesConstanttorqueloadsOutputpowervariesbuttorqueisconstantConveyors,rotarykilns,constant-displacementpumpsVariabletorqueloadsTorquevarieswithsquareofoperationspeedCentrifugalpumps,fansConstantpowerloadsTorquechangesinverselywithspeedMachinetools5©UNEP2006TrainingAgenda:ElectricMotorsIntroductionTypesofelectricmotorsAssessmentofelectricmotorsEnergyefficiencyopportunitiesElectricalEquipment/ElectricMotors6©UNEP2006TypeofElectricMotorsMotorsarecategorizedonthebasisofinputsupply,constructionandoperationprincipolesTEXTClassificationofMotorsElectricalEquipment/ElectricMotorsElectricMotorsAlternatingCurrent(AC)MotorsDirectCurrent(DC)MotorsSynchronousInductionThree-PhaseSingle-PhaseSelfExcitedSeparatelyExcitedSeriesShuntCompound7©UNEP2006TypeofElectricMotorsFieldpoleNorthpoleandsouthpoleReceiveelectricitytoform

magneticfieldArmatureCylinderbetweenthepolesElectromagnetwhencurrentgoesthroughLinkedtodriveshafttodrivetheloadCommutatorOverturnscurrentdirectioninarmatureDCMotors–ComponentsElectricalEquipment/ElectricMotors(DirectIndustry,1995)8©UNEP2006TypeofElectricMotorsSpeedcontrolwithoutimpactpowersupplyqualityChangingarmaturevoltageChangingfieldcurrentRestricteduseFewlow/mediumspeedapplicationsClean,non-hazardousareasExpensivecomparedtoACmotorsDCmotorsElectricalEquipment/ElectricMotors9©UNEP2006TypeofElectricMotorsRelationshipbetweenspeed,fieldfluxandarmaturevoltageDCmotorsElectricalEquipment/ElectricMotorsBackelectromagneticforce:E=K

NTorque:T=KIaE=electromagneticforcedevelopedatarmatureterminal(volt)

=fieldfluxwhichisdirectlyproportionaltofieldcurrentN=speedinRPM(revolutionsperminute)T=electromagnetictorqueIa=armaturecurrentK=anequationconstant10©UNEP2006TypeofElectricMotorsSeparatelyexcitedDCmotor:fieldcurrentsuppliedfromaseparateforceSelf-excitedDCmotor:shuntmotorElectricalEquipment/ElectricMotorsFieldwindingparallelwitharmaturewindingCurrent=fieldcurrent+armaturecurrentSpeedconstantindependentofloaduptocertaintorqueSpeedcontrol:insertresistanceinarmatureorfieldcurrentDCmotors(RodwellInt.Corporation,1999)11©UNEP2006TypeofElectricMotorsSelf-excitedDCmotor:seriesmotorElectricalEquipment/ElectricMotorsDCmotors(RodwellInt.Corporation,1999)FieldwindinginserieswitharmaturewindingFieldcurrent=armaturecurrentSpeedrestrictedto5000RPMAvoidrunningwithnoload:speeduncontrolledSuitedforhighstartingtorque:cranes,hoists12©UNEP2006TypeofElectricMotorsDCcompoundmotorElectricalEquipment/ElectricMotorsDCmotorsFieldwindinginseriesandparallelwitharmaturewindingGoodtorqueandstablespeedHigher%compoundinseries=highstartingtorqueSuitedforhighstartingtorqueifhigh%compounding:cranes,hoists13©UNEP2006TypeofElectricMotorsMotorsarecategorizedonthebasisofinputsupply,constructionandoperationprincipolesTEXTClassificationofMotorsElectricalEquipment/ElectricMotorsElectricMotorsAlternatingCurrent(AC)MotorsDirectCurrent(DC)MotorsSynchronousInductionThree-PhaseSingle-PhaseSelfExcitedSeparatelyExcitedSeriesShuntCompound14©UNEP2006TypeofElectricMotorsElectricalcurrentreversesdirectionTwoparts:statorandrotorStator:stationaryelectricalcomponentRotor:rotatesthemotorshaftSpeeddifficulttocontrolTwotypesSynchronousmotorInductionmotorACMotorsElectricalEquipment/ElectricMotors(IntegratedPublishing,2003)15©UNEP2006TypeofElectricMotorsConstantspeedfixedbysystemfrequencyDCforexcitationandlowstartingtorque:suitedforlowloadapplicationsCanimprovepowerfactor:suitedforhighelectricityusesystemsSynchronousspeed(Ns):ElectricalEquipment/ElectricMotorsACMotors–SynchronousmotorNs=120f/PF=supplyfrequencyP=numberofpoles16©UNEP2006TypeofElectricMotorsMostcommonmotorsinindustryAdvantages:SimpledesignInexpensiveHighpowertoweightratioEasytomaintainDirectconnectiontoACpowersourceElectricalEquipment/ElectricMotorsACMotors–Inductionmotor17©UNEP2006TypeofElectricMotorsElectricalEquipment/ElectricMotorsComponentsRotorSquirrelcage:

conductingbars

inparallelslotsWoundrotor:3-phase,double-layer,distributedwindingACMotors–InductionmotorStatorStingswithslotstocarry3-phasewindingsWoundfordefinitenumberofpoles(AutomatedBuildings)18©UNEP2006TypeofElectricMotorsElectricalEquipment/ElectricMotorsACMotors–InductionmotorHowinductionmotorsworkElectricitysuppliedtostatorMagneticfieldgeneratedthatmovesaroundrotorCurrentinducedinrotorElectromagneticsStatorRotorRotorproducessecondmagneticfieldthatopposesstatormagneticfieldRotorbeginstorotate(Reliance)19©UNEP2006TypeofElectricMotorsElectricalEquipment/ElectricMotorsACMotors–InductionmotorSingle-phaseinductionmotorOnestatorwindingSingle-phasepowersupplySquirrelcagerotorRequiredevicetostartmotor3to4HPapplicationsHouseholdappliances:fans,washingmachines,dryers20©UNEP2006TypeofElectricMotorsElectricalEquipment/ElectricMotorsACMotors–InductionmotorThree-phaseinductionmotorThree-phasesupplyproducesmagneticfieldSquirrelcageorwoundrotorSelf-startingHighpowercapabilities1/3tohundredsHPapplications:pumps,compressors,conveyorbelts,grinders70%ofmotorsinindustry!21©UNEP2006TypeofElectricMotorsElectricalEquipment/ElectricMotorsACMotors–InductionmotorSpeedandslipMotorneverrunsatsynchronousspeedbutlower“basespeed”Differenceis“slip”InstallslipringtoavoidthisCalculate%slip:%Slip=Ns–Nb

x100NsNs=synchronousspeedinRPMNb=basespeedinRPM22©UNEP2006TypeofElectricMotorsElectricalEquipment/ElectricMotorsACMotors–InductionmotorRelationshipload,speedandtorqueAtstart:highcurrentandlow“pull-up”torqueAtstart:highcurrentandlow“pull-up”torqueAt80%offullspeed:highest“pull-out”torqueandcurrentdropsAtfullspeed:torqueandstatorcurrentarezero23©UNEP2006TrainingAgenda:ElectricMotorsIntroductionTypesofelectricmotorsAssessmentofelectricmotorsEnergyefficiencyopportunitiesElectricalEquipment/ElectricMotors24©UNEP2006AssessmentofElectricMotorsMotorslooseenergywhenservingaloadFixedlossRotorlossStatorlossFrictionandrewindingStrayloadlossEfficiencyofElectricMotorsElectricalEquipment/ElectricMotors(USDOE)25©UNEP2006FactorsthatinfluenceefficiencyAgeCapacitySpeedTypeTemperatureRewindingLoadEfficiencyofElectricMotorsElectricalEquipment/ElectricMotorsAssessmentofElectricMotors26©UNEP2006MotorpartloadefficiencyDesignedfor50-100%loadMostefficientat75%loadRapiddropbelow50%loadEfficiencyofElectricMotorsElectricalEquipment/ElectricMotors(USDOE)AssessmentofElectricMotors27©UNEP2006MotorloadisindicatorofefficiencyEquationtodetermineload:MotorLoadElectricalEquipment/ElectricMotorsLoad=Pix

HPx0.7457

=Motoroperatingefficiencyin%HP =NameplateratedhorsepowerLoad =Outputpowerasa%ofratedpowerPi =ThreephasepowerinkWAssessmentofElectricMotors28©UNEP2006ThreemethodsforindividualmotorsInputpowermeasurementRatioinputpowerandratepowerat100%loadingLinecurrentmeasurementComparemeasurederagewithratederageSlipmethodCompareslipatoperationwithslipatfullloadMotorLoadElectricalEquipment/ElectricMotorsAssessmentofElectricMotors29©UNEP2006InputpowermeasurementThreestepsforthree-phasemotorsStep1.Determinetheinputpower:MotorLoadElectricalEquipment/ElectricMotorsPi =ThreePhasepowerinkWV =RMSVoltage,meanlineto lineof3PhasesI =RMSCurrent,meanof3phasesPF =PowerfactorasDecimalAssessmentofElectricMotors30©UNEP2006InputpowermeasurementStep2.Determinetheratedpower:Step3.Determinethepercentageload:MotorLoadElectricalEquipment/ElectricMotorsLoad =OutputPowerasa%ofRatedPowerPi =MeasuredThreePhasepowerinkWPr =InputPoweratFullRatedloadinkWPr =InputPoweratFullRatedloadinkWhp =NameplateRatedHorsePower

r =EfficiencyatFullRatedLoadAssessmentofElectricMotors31©UNEP2006Result SignificantlyoversizedandunderloadedModeratelyoversizedandunderloadedProperlysizedbutstandardefficiencyMotorLoadElectricalEquipment/ElectricMotorsActionReplacewithmoreefficient,properlysizedmodels

Replacewithmoreefficient,properlysizedmodelswhentheyfailReplacemostofthesewithenergy-efficientmodelswhentheyfailAssessmentofElectricMotors32©UNEP2006TrainingAgenda:ElectricMotorsIntroductionTypesofelectricmotorsAssessmentofelectricmotorsEnergyefficiencyopportunitiesElectricalEquipment/ElectricMotors33©UNEP2006UseenergyefficientmotorsReduceunder-loading(andavoidover-sizedmotors)SizetovariableloadImprovepowerqualityRewindingPowerfactorcorrectionbycapacitorsImprovemaintenanceSpeedcontrolofinductionmotorElectricalEquipment/ElectricMotorsEnergyEfficiencyOpportunities34©UNEP2006ReduceintrinsicmotorlossesEfficiency3-7%higherWiderangeofratingsMoreexpensivebut

rapidpaybackBesttoreplacewhen

existingmotorsfailUseEnergyEfficientMotorsElectricalEquipment/ElectricMotors(BureauofIndianStandards)EnergyEfficiencyOpportunities35©UNEP2006ElectricalEquipment/ElectricMotorsPowerLossAreaEfficiencyImprovement1.Fixedloss(iron)Useofthinnergauge,lowerlosscoresteelreduceseddycurrentlosses.Longercoreaddsmoresteeltothedesign,whichreduceslossesduetoloweroperatingfluxdensities.2.StatorI2RUseofmorecopper&largerconductorsincreasescrosssectionalareaofstatorwindings.Thislowerresistance(R)ofthewindings&reduceslossesduetocurrentflow(I)3RotorI2RUseoflargerrotorconductorbarsincreasessizeofcrosssection,loweringconductorresistance(R)&lossesduetocurrentflow(I)4Friction&WindingUseoflowlossfandesignreduceslossesduetoairmovement5.StrayLoadLossUseofoptimizeddesign&strictqualitycontrolproceduresminimizesstrayloadlosses(BEEIndia,2004)UseEnergyEfficientMotorsEnergyEfficiencyOpportunities36©UNEP2006EnergyEfficiencyOpportunitiesReasonsforunder-loadingLargesafetyfactorwhenselectingmotorUnder-utilizationofequipmentMaintainoutputsatdesiredlevelevenatlowinputvoltagesHighstartingtorqueisrequiredConsequencesofunder-loadingIncreasedmotorlossesReducedmotorefficiencyReducedpowerfactor2.ReduceUnder-loadingElectricalEquipment/ElectricMotors37©UNEP2006EnergyEfficiencyOpportunitiesReplacewithsmallermotorIfmotoroperatesat<50%Notifmotoroperatesat60-70%OperateinstarmodeIfmotorsconsistentlyoperateat<40%InexpensiveandeffectiveMotorelectricallydownsizedbywirereconfigurationMotorspeedandvoltagereductionbutunchangedperformance2.ReduceUnder-loadingElectricalEquipment/ElectricMotors38©UNEP2006EnergyEfficiencyOpportunitiesMotorselectionbasedonHighestanticipatedload:expensiveandriskofunder-loadingSlightlylowerthanhighestload:occasionaloverloadingforshortperiodsButavoidriskofoverheatingduetoExtremeloadchangesFrequent/longperiodsofoverloadingInabilityofmotortocooldown

3.SizingtoVariableLoadElectricalEquipment/ElectricMotorsX

Motorshave‘servicefactor’of15%aboveratedload39©UNEP2006EnergyEfficiencyOpportunitiesMotorperformanceaffectedbyPoorpowerquality:toohighfluctuationsinvoltageandfrequencyVoltageunbalance:unequalvoltagestothreephasesofmotor4.ImprovePowerQualityElectricalEquipment/ElectricMotorsExample1Example2Example3Voltageunbalance(%)0.302.305.40Unbalanceincurrent(%)0.417.740.0Temperatureincrease(oC)0304040©UNEP2006EnergyEfficiencyOpportunitiesKeepvoltageunbalancewithin1%BalancesinglephaseloadsequallyamongthreephasesSegregatesinglephaseloadsandfeedthemintoseparateline/transformer4.ImprovePowerQualityElectricalEquipment/ElectricMotors41©UNEP2006EnergyEfficiencyOpportunitiesRewinding:sometimes50%ofmotorsCanreducemotorefficiencyMaintainefficiencyafterrewindingbyUsingqualified/certifiedfirmMaintainoriginalmotordesignReplace40HP,>15yearoldmotorsinsteadofrewindingBuynewmotorifcostsarelessthan50-65%ofrewindingcosts5.RewindingElectricalEquipment/ElectricMotors42©UNEP2006EnergyEfficiencyOpportunitiesUsecapacitorsforinductionmotorsBenefitsofimprovedPFReducedkVAReducedlossesImprovedvoltageregulationIncreasedefficiencyofplantelectricalsystemCapacitorsizenot>90%ofno-loadkVARofmotor6.ImprovePowerFactor(PF)ElectricalEquipment/ElectricMotors43©UNEP2006EnergyEfficiencyOpportunitiesChecklisttomaintainmotorefficiency