3856 motor maxwell2d
TRANSCRIPT
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StudyofaPermanentMagnetMotorwith
MAXWELL2D:
Exampleofthe2004PriusIPMMotor
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Studyofanelectricalmachine
TheElectroMechanicalsoftwarepackageprovidedbyAnsoftenablesextensiveelectricalmalchinesimulation.ThisapplicationnotedetailsthesimulatonofanelectricalmachinewithMaxwel2D.Wewillcoverstaticandtransientsimulations.
Thisapplicationnotewillusethe2004ToyotaPriusmotorasbasis.Itisa8-polepermanentmagnetmotorwithembeddedmagnets.Thesinglelayerwindingsaremadeof3phases.Thestatorhas48slots.Thismotorispublic,wethereforehavethefullsetofparameters.WewillalsouseOakRidgeNationalLaboratorytestingresultsinthisnote.
Note:ThisapplicationhasnotbeendonewiththecollaborationofToyota
References:Report on Toyota/Prius Motor Torque Capability, Torque Property, No-Load Back EMF,and Mechanical Losses,J.S.Hsu,Ph.D.,C.W.Ayers,C.L.Coomer,R.H.Wiles
OakRidgeNationalLaboratory
Report on Toyota/Prius Motor Design and manufacturing AssessmentJ.S.Hsu,C.W.Ayers,C.L.Coomer
OakRidgeNationalLaboratory
Evaluation of 2004 Toyota Prius Hybrid Electric Drive System Interim ReportC.W.Ayers,J.S.Hsu,L.D.Marlino,C.W.Miller,G.W.Ott,Jr.,C.B.Oland
OakRidgeNationalLaboratory
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OverviewoftheStudy:
GETTINGSTARTED
Creatingthe3DModel
Reducingthesizeofthe3DModel
Materialpropertiesofthemachine
ApplyingMaster/SlaveBoundaryCondition
STATICANALYSIS
DYNAMICANALYSIS
COGGINGTORQUE
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GettingStarted
LaunchingMaxwell1. ToaccessMaxwell,clicktheMicrosoftStart button,selectPrograms>Ansoft>Maxwell 12.SettingToolOptions
To set the tool options:Note: Inordertofollowthestepsoutlinedinthisexample,verifythatthefollowingtooloptionsareset :
1. SelectthemenuitemTools > Options > Maxwell 2D Options2. MaxwellOptionsWindow:
1. ClicktheGeneral Options tabUseWizardsfordataentrywhencreatingnewboundaries:CheckedDuplicateboundarieswithgeometry: Checked
2. ClicktheOK button3. SelectthemenuitemTools > O ptions > M odeler Options.4. 3DModelerOptionsWindow:
1. ClicktheOperation tabAutomaticallycoverclosedpolylines: Checked
2. ClicktheDrawing tabEditpropertyofnewprimitives: Checked
3. ClicktheOK button
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OpeningaNewProjectTo open a new project:
1. InanMaxwellwindow,clickthe iconontheStandardtoolbar,orselectthemenuitemFile > New .
2. Rightmouseclickontheprojectname,thenselectthemenuitemRename.ChangetheprojectnametoPrius
3. SelectthemenuitemProject > Insert Maxwell Des ign, orclickontheicon
4. RightmouseclickonMaxwelldesign1andselectRename.Changethenameto1_Whole_Motor
5. ClickonthemenuitemMaxwell 2D > Solution TypeGeometryMode:Cartesion XYMagnetic:Transient
SetModelUnitsSelectthemenuitemModeler > Units. SelectUnits: mm (millimeters)
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Creatingthe2DModel
MaxwellhasnumberofUser Defined Primitives formotorparts.Theseprimitivescandescribeallthemainpartsofmotors.
CreatetheStator:AUserDefinedPrimitivewillbeusedtocreatethestator
Selectthemenuitem Draw > User Defined Primitive > Syslib > Rmxprt >SlotCoreUsethevaluesgiveninthepanelbelowtocreatethestator
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Creatingthe2DModel(Continued)
Clickonthejustcreatedobjectinthedrawingwindowandinthepanelontheleft
changeitsnamefromSlotCore1 toStatorNote:thematerialwillbeappliedafterwards
CreatetheRotor
AUserDefinedPrimitivewillbeusedtocreatetherotor
Selectthemenuitem Draw > User Defined Primitive > Syslib > Rmxprt >IPMCoreUsethevaluesgiveninthepanelnextpagetocreatetherotor
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Creatingthe2DModel(Continued)
Clickonthejustcreatedobjectinthedrawingwindowandinthepanelontheleft
changeitsnamefrom IPMCore1 toRotor
CreatetheMagnets
ThesameUserDefinedPrimitivecanbeusedtocreatethemagnets,butwith
differentparameters.UDPscanbecomputedtogeneratedifferenttopologies.
SelecttheobjectRotor.CopyandpastetheobjectusingtheCtrl+C,Ctrl+Vcommands.AnobjectRotor1 iscreated
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Creatingthe2DModel(Continued)
Onthemodelertree,doubleclickonthecommandCreateUserDefinedPartoftheobjectRotor1
ChangetheInfoCorelinefrom0(Core)to1(Magnets)
ChangethenameoftheobjectfromRotor1 toMagnetsChangethemagnetscolorfromdefaulttoalightred.
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Creatingthe2DModel(Continued)
CreatetheWindings
AnUserDefinedPrimitivewillalsobeusedtocreatethewindings.
Selectthemenuitem Draw > User Defined Primitive > Syslib > Rmxprt > LapCoilUsethevaluesgiveninthepanelbelowtocreatethecoil
ChangetheMaterialfromvacuum toCopperSelecttheobjectLapCoil1,changeitscolortoyellow
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Creatingthe2DModel(Continued)
SelecttheobjectLapCoil1,andtoapplyarotationof7.5 degalongtheZ axis,rightmouseclick,andselectthemenuitemEdit > Arrange > R otate orusetheicon.
SelecttheobjectLapCoil1.ThiscoilconstitutesthefirstcoilofPhaseA.WenowduplicatethiscoiltocreatethefirstcoilsofPhaseCandB.RightMouseclick,
andselectthemenuitemEdit > Duplicate > Around Axis orusetheicon.
ChangetheNameofobjectsLapCoil1_1 andLapCoil1_2 toPhaseC andPhaseB.ChangethecolorofPhaseC todarkgreenandthecolorofPhaseB tolightblue.RenameLapcoil1 toPhaseA.
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Creatingthe2DModel(Continued)
SelecttheobjectsPhaseA ,PhaseB andPhaseC.RightMouseclick,andselectthemenuitemEdit > Dup licate > Around Axis orusetheicon.Enter45degreesand8 forthetotalnumber.Thiswillcreatealltherequiredcoils.
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Creatingthe2DModel(Continued)
Thegeometryofthemotoriscompleted.
Dependingonthesolverandthemotorperformancedatathatwewanttolookat,wemighthavetoaddmoreobjects(formeshingormovementsetting).
Savetheproject.ClickontheMaxwelldesign1_Whole_motor,rightmouseclickandselectCopy.
Clickontheprojectname,rightmouseclickandselectPaste.Changethecopieddesignto2_Partial_motor.Wecantakeadvantageofthetopologyofthemotortoreducethesizeoftheproblem.Thismotorhas8pairofpoles.Wecanonlyuseoneheightofthemotor.Thisisvalidbecausethestatorhas:
48slots(8isadividerof48).
The3-phasewindinghasalsoaperiodicityof45degrees.
Fromnowon,theMaxwelldesign2_Partial_motorwillbeused.Wehavesavedacopyofthewholegeometryasitwillbeusedlaterforotherstudies.
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Reducingthesizeofthe2DModel(Continued)
Selectalltheobjectsfromthemodelertree(oryoucanusethectrl-A command).RightmouseclickandselectEdit > Boo lean > Split orusethetoolbaricon.SelecttheXZ planeandkeepthepositive side.
Note:Duringtheprocess,alotofmessageswillappearinthedialogbox.These
messagesinformthatsomeobjectsnolongerexistastheyentirelylieoutsidethe
remainingmodel.Weobtainhalfofthemotor.Maintaintheobjectsselected,rightmouseclickand
selectEdit > Arrange > Ro tate orselectthetoolbaricon.Enter-45 degfortherotationaroundtheZ axis.
Maintaintheobjectsselected,RightmouseclickandselectEdit > Boolean > Splitorusethetoolbaricon.SelecttheXZ planeandkeepthenegative side.Maintaintheobjectsselected,rightmouseclickandselectEdit > Arrange >Rotate orselectthetoolbaricon.Enter45 degfortherotationaroundtheZaxis
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Reducingthesizeofthe2DModel(Continued)
The3Dmodelnowlookslikebelow
RenamePhaseA toPhaseA1 andPhaseA_7 toPhaseA2.RenamePhaseB ,PhaseB_7,PhaseC andPhaseC_7 toPhaseB1,PhaseB2,PhaseC1 andPhaseC2.WecannowcreatetheRegionaroundthemotor.Mostofthefluxisconcentratedwithinthemotor,sowedonotneedtohavealargeRegion.
SelectDraw > Line1. Usingthecoordinateentryfield,entertheboxposition
X: 0.0, Y: 0.0, Z: 0.0,PresstheEnter key2. Usingthecoordinateentryfield,entertherelativesizeoftheboxdX: 200.0, dY: 0.0, dZ: 0.0,PresstheEnter key3. ClickEnter asecondtimetofinishthedrawing
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Reducingthesizeofthe2DModel(Continued)
SelectPolyline1.RightmouseclickandselectEdit > Sweep > Around Axis.Entertheparametersasspecifiedinthepanelbelow:
RenametheRegionfromPolyline1 toRegion.MakesurethatVacuumistheselectedmaterial.Also,youmightwanttomodifytherenderoftheRegion byincreasingthetransparency.
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Materialpropertiesofthemotor
PermanentMagnetscharacterization.
ThePriusPermanentMagnets(PMs)arehigh-strengthmagnets.
InordertodefinePMsmagnetizationorientation,weneedtocreateseparate
objectsforeachmagnet.SelecttheobjectMagnets.Rightmouseclick,selectEdit > Boolean > S eparate Bodies.RenametheobjectsfromMagnets toPM1andfromMagnets_Separate1 to PM2.Sincethemagnetswillrotate,theorientationcannotbegiventhroughfixedcoordinatesystems(CS).TheuseoffaceCSisrequired.FaceCSareCSthat
areattachedtothefaceofanobject.Whentheobjectmoves,theFaceCSalso
movesalongwiththeobject.
ThePriussPMsareorientedasshownbelow.Therefore,wewillcreateafaceCSforeachmagnet.
SwitchtheselectmodefromObjecttoFacebyclickingonthefbuttonorbyusingthetoolbaricon:
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Materialpropertiesofthemotor(Continued)
ThefaceCSiscreated.ItsdefaultnameisFaceCS1.ChangeitsnamefromFaceCS1 toPM1_CS .
RepeatthesameoperationtocreatethefaceCSPM2_CS attachedtoPM2.MakesuretohavetheXaxislookingtowardtheairgap
ResettheworkingCStotheGlobalCSbyclickingonGlobal asshownbelow.
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Materialpropertiesofthemotor(Continued)
EdittheattributesoftheobjectPM1.ModifytheOrientationoftheobjectbyselectingthePM1_CS coordinatesystem.ThisCSwillbethereferenceforthemagnetizationdirection.
Toenterintothematerialdatabase,clickontheMaterialbutton(thedefault
materialisVacuum).ThePriusmagnetisnotpartofthedefaultlibrary,soclickontheAddmaterialbutton
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Materialpropertiesofthemotor(Continued)
WehaveaspecialmenutoenterPermanentMagnetparameters.Atthebottom
oftheView/Editmaterialwindow,selectthePermanentMagnetentry.
Enterthevaluesgivenbelowtodefinethemagnetstrength
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Materialpropertiesofthemotor(Continued)
ChangethematerialnametoN36Z_20.IfthecoordinatesystemPM1_CS issuchthattheX axis goesintheoppositedirectionoftheairgapaccordinglytotheimagebelow,leavetheXorientationto
1and0fortheYandZcomponents.IftheXaxiswasintheoppositedirection,
youwouldneedtoenter-1fortheXcomponent.
ClickontheValidatebuttonbeforeclosingthewindowtocheckthematerial
definition.
EdittheattributesoftheobjectPM2.ModifytheOrientationoftheobjectbyselectingthePM2_CS coordinatesystem.ThisCSwillbethereferenceforthemagnetizationdirection.IfthedefinitionofPM2_CSisconsistentwithPM1_CS(
Xaxisinthedirectionoftheairgap),youcanusethesamematerialforN36Z_20forPM2.Ifitisnotthecase,youcanclonethematerialN36Z_20 andchangetheorientationtobeconsistentwiththePM2_CS axis.
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Materialpropertiesofthemotor(Continued)
Steeldefinition
Thestatorandrotorsharesthesamematerial.SelecttheobjectsStator andRotor.Edittheirattributes,changetheaffectedmaterial.Inthematerialdatabase,addanewmaterialcalledM19_29G.Thesteelisnonlinear.Toenterthenon-linearB-HCharacteristic,changethe
RelativePermeabilityfromSimpletoNonlinear
ClickontheBHcurvebuttonintheValuecolumn.TheBHcurveentrywindowappears
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Materialpropertiesofthemotor(Continued)
EntertheB-Hcharacteristicswiththevaluesgivenbelow
H B
0 0
22.28 0.05
25.46 0.1
31.83 0.15
47.74 0.3663.66 0.54
79.57 0.65
159.15 0.99
318.3 1.2
477.46 1.28
636.61 1.33
795.77 1.36
1591.5 1.44
3183 1.52
4774.6 1.58
6366.1 1.63
7957.7 1.67
15915 1.8
31830 1.9
111407 2
190984 2.1
350138 2.3
509252 2.5
560177.2 2.563994494
1527756 3.779889874
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Materialpropertiesofthemotor(Continued)
WeneglecttheEddycurrentinthisexample,thereforeweleavetheconductivity
to0.
ValidatethematerialbeforeexitingtheView/Editmaterialwindow
MakesurethatM19_29G isaffectedtotheRotor andStator.
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Coreloss
Thissectionisonlynecessaryifyouwishtocomputethecorelossofthemotor.
IntheTransientsolver,weareabletocomputecoreloss(orhystererisloss),
strandedlossandeddycurrentloss(orproximityloss).Wewillonlyconsider
corelossinthisdocument.
Weneedtoenterthelossvaluesofthesteel.Adedicatedmenuenablestheuser
toenterthedata.
Extendtheprojecttree,anddoubleclicktheMaterialdefinitionoftheSteel
M19_29G
UsethepulldownmenutoenablecorelossforElectrical Steel material
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Coreloss(Continued)
TheMaxwellsolverrequiresthecoefficientsKh,Kc,KeandKdc.Aspecialmenu
allowsthecoefficientstobederivedfrommanufacturercorelossdata
Selectatthebottomofthematerialdefinitionwindowfromthepulldownmenu
CoreLossversusFrequency
TheCoreLossversusFrequencymenupopsup.Weprovidethedataforseveral
frequencies:
1. SelectW/kg fortheCoreLossUnit2. Enter7872 kg/m3 fortheMassdensityoftheSteel3. Enter50 Hz intheEditwindow4. ClickonAdd5. ClickonEdit Dataset intheFrequencyWindow
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Coreloss(Continued)
Thecorelosscoefficientareautomaticallycalculated
Acceptthesetting.Thematerialdefinitionnowincludesthecorelosscoefficients
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ApplyingMaster/SlaveBoundaryCondition
TheMasterandSlaveboundaryconditiontakesadvantageoftheperiodicityof
themotor.Twoplanesaretobedefined:themasterandslaveplanes.TheH-
fieldateverypointontheslavesurfacematchesthe(plusorminus)H-fieldat
everypointonthemastersurface.
SelecttheobjectRegion fromtheactiveview.Rightmouseclick,thenselectView> Show In A ctive View asshownbelow
ChangetheSelectmodetoEdge
SelectoneoftheboundinglineoftheRegion
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ApplyingMaster/SlaveBoundaryCondition(Cond)
Rightmouseclick,selectAssign Boundary > Master
Thevectoruisdefinedcorrectly.Acceptthesetting.
SelecttheoppositeedgeoftheRegion
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ApplyingMaster/SlaveBoundaryCondition(Contd)
Rightmouseclick,selectAssign Boundary > Slave
1. Wefirstneedtogivethereferenceofthemastercondition.FortheMaster
Boundary,sincewehaven'tchangedthedefaultname,SelectMaster12. SelectSwap direction fortheuvectordefinitionifthevectorudoesnot
havethesamedirectionthantheuvectoroftheMastercondition.
3. Themodelrepresentsonepoleoutofheight.Sincewerepresentanodd
numberofpoles,theconditionattheslavesurfaceisSlave=-Master
4. Acceptthesetup
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ApplyingZeroVectorPotentialBoundaryCondition
AtthelimitoftheRegion,selectthefivesegmentsoftheoutsidelimitoftheRegion.UsetheCtrlbuttontoallowmultiselections
RightMouseClick,SelectAssign Boundary > Vector Potential
1. Put0 Weber/mforthevalue2. NametheconditionZero_Flux
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STATICANALYSIS
Wewillstudythedifferentstaticparametersofthemotor.
Savetheproject.ClickontheMaxwelldesign2_Partial_motor,rightmouseclickandselectCopy.
Clickontheprojectname,rightmouseclickandselectPaste.Changethecopied
designto3_Partial_motor_MS.
NoLoadStudy
Thefirstanalysisthatwillbeperformedconsistsincomputingthefieldsdueto
thepermanentmagnets.
TheCoilsarenotneededinthemodelsincenocurrentisdefined.Selectthe6
coils.Then,UnchecktheradiobuttonModelfromthepropertywindow.NotethattheNameofobjectlineisemptysincewehaveselectedseveralobjects.
LeavetheCoilsselected,andHidethecoilsbyselectingthemenuitemView >Hide Selection > Active view orusingthetoolbarbutton
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se
ApplyMeshOperations
Theadaptivemeshingisveryeffective,soitisnotnecessarytoenterdedicatedmeshoperations.However,itisalwaysagoodideatostartwithadecentinitialmeshinordertoreducetimecomputationsinceweknowwherethemeshneedstoberefinedforamotor.Thenonlinearresolutionwillbefasterwithasmallaspectratiosfortheelementsinthesteel.
SelecttheRotor.RightMouseClickandSelectAssign Mesh Operation > InsideSelection > Length Based
Restrictthelengthofelementsto5 mm.RenamethemeshoperationRotor
SelecttheStator.Wewanttominimizethenumberofelementsforthecurvedlineoftheslots.RightMouseClickandSelectAssign Mesh Operation > SurfaceApproximation.
Input30deg fortheMaximumsurfacedeviationSelect5 fortheMaximumaspectRatio.RenamethemeshoperationSA_Stator
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ApplyMeshOperations(Continued)
SelectPM1 andPM2.RightMouseClickandSelectAssign Mesh Operation >Inside Selection > Length Based
Restrictthelengthofelementsto3 mm.RenamethemeshoperationMagnets
ApplyTorquecomputation
SelecttheobjectsPM1,PM2 andRotor.RightmouseclickandselectAssignParameters > Torque
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AddanAnalysisSetup
Fromtheprojectmanager,rightmouseclickonAnalysis andselectAdd So lutionSetup:
1. Enter10forthemaximumnumberofpasses
2. Enter0.1%fortheerror
3. Intheconvergencepanel,enter15%fortherefinement
4. MakesurethattheNonResidualissetto0.0001%.ClickOktorecordthe
analysissetup
Analyse
RightmouseclickonthesetupetselectAnalyzeorclickontheicon.
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Postprocessing
Thecomputationtakes7passestoconverge.TheConvergencepanelcanbe
seenbyrightmouseclickingonSetup1,selectingthemenuitemConvergence
Torque value. SelecttheSolutionstab,thetorqueisgivenforaonemeterdepthmotor.Thetorqueforthefullmotorneedstobemultipliedby8(symmetryfactor),
thenby0.082(toaccountforthemotorlength).Thisgives2.5mN.m,which
soundsreasonable:thevalueisverysmallinregardstothefullloadoperation.
Differentanglesbetweentherotorandthestatorwouldgivedifferentvalues.
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PostProcessing(Contd)
Plot magnetic flux density.SelecttheRotor,Stator,PM1, PM2 rightmouseclick,selectAll Object Faces.Rightmouseclickagainandselect Fields > B > Mag_B.WeobtainthedistributionofB ontheobjects.Thesteelishighlysaturatedclosetothemagnetsasexpected.Thissaturationsappearsjustbecauseofthemagnetsstrengths.
Plot the magnetic flux strength H in the air gap.Weneedtodrawapost-processinglinetoviewthefield:
1. Drawanarc.SelectthemenuitemDraw>Arc>CenterPointorusethecorrespondingtoolbaricon
2. Accepttocontinuetodrawanonmodelobject.Thiswillnotinvalidatetheexistingsolution
3. Enterthecenterofthearc:0,0,0 mm andhitenter
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PostProcessing(Contd)
4. Enterthefirstpointofthearc.Thispointisatthemiddleoftheairgapon
theYZplane.Enter80.575, 0 , 0 mm andhitenter.
5. Enterthelastpointofthearc.ThispointliesontheplaneXY,witha45
anglewiththeX- axis.80.575/2=56.70996().Enter56.70996, 56.70996,0 mm andhitenter.
6. Tofinishthearc,movethemouseonthedrawingarea,rightmouseclick,
andselectthemenuentrydone
7. Namethepolylineairgap_arc andaccepttheobject
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PostProcessing(Contd)
8. AnewfolderLineshasappearedontheobjecttree,containingthenewdefinedarc.
9. Selectthelineairgap_arc,movethemouseonthedrawingarea,rightmouseclick,thenselectthemenuitemFields > H > H_vector.
10. AccepttheFieldplotsetting
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PostProcessing(Contd)
11. ThevectorplotofHappearswiththedefaultsetting.Tocustomizethe
display,doubleclickonthescalezone:
12. Youcanmodifythedefaultsettingsinthedifferenttabslikebelow:
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FullLoadStudy
Savetheproject.ClickontheMaxwelldesign3_Partial_motor_MS ,rightmouseclickandselectCopy.Clickontheprojectname,rightmouseclickandselectPaste.Changethecopieddesignto4_Partial_motor_MS2.Inthisdesign,weapplycurrentinthecoils:weneedtoincludethecoilsinthemodel.Selectthe6coilsfromthemodelertree.Inthepropertywindow,selecttheradiobuttonModel.
UnhidethecoilsbyselectingthemenuitemView> Show se lections> All views
ApplyExcitations
Thecoilsarepartiallyrepresentedinthemodel.Weneedtoenterthecurrentthatflowsinandoutinsideeachcoil.Theexcitationisrealizedthroughabalancedthreephasesystem.Forinstance,inourexample,weapply:
1500AtoPhaseA
-750AtoPhaseB
-750AtoPhaseC.
IntheMagnetosaticsolver,thesourcesaregivenintermsofcurrents.Wedonotneedtomodeleachturnatthisstage;thereforeweonlyenterthetotalcurrentineachphase.Thenumberofturnsandtheelectricaltopologyareonlytakenintoaccountfortheinductancescalculation.
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ApplyExcitations(Contd)
Switchtheselectionmodetoface
EnterExcitationforCoilPhaseA2:1. SelectthePhaseA2
2. Rightmouseclick,selectthemenuitemApply Exc itation > Current3. RenametheExcitationPhaseA24. Enter1500A5. Asthedefaultcurrentdirectionplottedinredisgood,leavePositive6. ValidatetheExcitation
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ApplyExcitations(Contd)
Switchtheselectionmodetoface
EnterExcitationforCoilPhaseA11. SelectthePhaseA1
2. Rightmouseclick,selectthemenuitemApply Exc itation > Current3. RenametheExcitationPhaseA14. Enter1500A5. Asthedefaultcurrentdirectionplottedinredisgood,leavePositive6. ValidatetheExcitation
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ApplyExcitations(Contd)
Switchtheselectionmodetoface
EnterExcitationforCoilPhaseC21. SelectthePhaseC2
2. Rightmouseclick,selectthemenuitemApply Exc itation > Current3. RenametheExcitationPhaseC24. Enter-750A5. Asthedefaultcurrentdirectionplottedinredisnotgood,chooseNegative6. ValidatetheExcitation
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ApplyExcitations(Contd)
Switchtheselectionmodetoface
EnterExcitationforCoilPhaseB21. SelectthePhaseB2
2. Rightmouseclick,selectthemenuitemApply Exc itation > Current3. RenametheExcitationPhaseB24. Enter-750A5. Asthedefaultcurrentdirectionplottedinredisgood,leavePositive6. ValidatetheExcitation
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ApplyExcitations(Contd)
Switchtheselectionmodetoface
EnterExcitationforCoilPhaseB11. SelectthePhaseB1
2. Rightmouseclick,selectthemenuitemApply Exc itation > Current3. RenametheExcitationPhaseB14. Enter-750A5. Asthedefaultcurrentdirectionplottedinredisgood,leavePositive6. ValidatetheExcitation
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Inductancecomputation
Weareinterestedbytheinductancescomputation.Thesourcesetupis
independentfromthewindingarrangement:wehaveonlyenteredthe
correspondingamp-turnsforeachterminal.Whenlookingattheinductances,we
obviouslyneedtoenterthenumberofturnsforthecoilsandalsohowthecoils
areelectricallyorganized.
SelectParametersintheprojecttree,rightmouseclickandselectAssign >Matrix
Includethe6phasesinthematrixcomputation.Theinductancesarecomputed
for1turnatthisstage.
SelectthePostProcessingtab.Wedefineinthispanelthenumberofturnsfor
eachcoil.Enter9 forthesixcoils.Wealsowanttogroupallthecoilsofthesamephase.Thiswillenableustohavetheinductanceoftheentirewinding
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Inductancecomputation(Contd)
SelectthePhaseA1_in andPhaseA2_in entries,theyhitthegroupbutton.NameThegroupPhaseA
Repeattheoperationforthe3phases
AnalyseRightmouseclickonthesetupetselectAnalyzeorclickontheicon.
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Postprocessing
Thecomputationtakes6passestoconverge.TheConvergencepanelcanbe
seenbyrightmouseclickingonSetup1,selectingthemenuitemConvergence
Inductancevalues.SelecttheSolutions tab.Theinductanceforeachcoilsappears.Itisassumedthateachcoilhasonlyoneturn.
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Postprocessing(Contd)
SelecttheradiobuttonPost Processed.Theinductanceforeachwindingisdisplayed
Note: itispossibletoexporttheinductancematrixtoSimplorerusingtheExportCircuit button
Torque value. SelecttheSolutionstab,SelectfromthepulldownmenuTorque1.Thetorqueforthefullmotorneedstobemultipliedby8(symmetry
factor),thenmultipliedby0.083(lengthofthemotor).Thisgivesaround47N.m.
Inthiscase,wehavenotsynchronizedthepositionoftherotorpoleswiththe
windingcurrents,sowearefarfromtheoptimizedexcitationvaluetoobtaina
maximumtorque.Differentanglesbetweentherotorandthestatorwouldgive
differentvalues.
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Postprocessing(Contd)
Plot the H field on the plane XY.SelecttheplaneXYbelongingtotheglobalCoordinateSysteminthemodelertree
Movethemousepointertothedrawingarea,rightmouseclickandselectthe
menuitemFields > H > H_vector
Validatethesetting
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Postprocessing(Contd)
Withthedefaultparameters,theHvectorsaretoosmall.Doubleclickonthe
scalezone
OntheColorMaptab,unchecktheReal time mode buttonandchangethenumberofcolorsto50
OntheScaletab,ChecktheUse Limits button,thenEnter1 and1e6 forthelimits.Also,ChecktheLog buttontohavealogscale.
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PostProcessing(Contd)
OntheMarker/Arrowtab,reducethesizeofthearrow,thenunchecktheMapsize andArrow tail buttons.OnthePlotstab,makesuretherightplotcontextisselected,thenmodifytheVectorplotminandmaxto1and5
Weobtainthefollowingplot.TheHfieldisstrongeraroundphaseAastheinput
currentishigher.
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DYNAMICANALYSIS
Wewillstudythetransientcharacteristicofthemotor.
Savetheproject.ClickontheMaxwelldesign2_Partial_motor,rightmouseclickandselectCopy.
Clickontheprojectname,rightmouseclickandselectPaste.Changethecopied
designto5_Partial_motor_TR.
Selectthedesignnamefromtheprojectmanager,Rightmouseclickandchange
thesolutiontypefromMagnetostatic toTransient:
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ThetransientsolveractsdifferentlyfromtheMagnetostaticsolvermainly
because:
Thereisnotadaptivemeshing.Sincethegeometrychangesateverytime
step,Maxwelldoesnotre-meshateverytimestepadaptivelyforobvious
timereason.Intransientanalysis,wewillbuildagoodmeshvalidforallthe
rotorpositions.
Thesourcesdefinitionisdifferent.InMagnetostatic,wewereonly
interestedinthetotalcurrentflowingintoconductor.InTransient,weuse
strandedconductors(theexactnumberofconductorsisrequiredforeach
winding)asthecurrentcanbeanarbitrarytimefunction.Weneedtocreate
dedicatedcoilsandwindings.
CreateCoils
Selectthe6coilsPhaseA1, PhaseA2, PhaseB1, PhaseB2, PhaseC1 andPhaseC2.RightmouseclickandselectthemenuitemAssign Exc itation > Coil
1. Leavethedefaultnameasitwillbeautomaticallyaffectedusingthe
objectsname
2. Enter9forthenumberofconductors
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CreateCoils(Contd)
Thesixcoilsdefinitionsareprocessed.
WeneedtochangetheorientationofthecoilsforPhaseC1 andPhaseC2:1. SelectPhaseC1,intheProjectManagerTree2. RightmouseclickandselectProperties
3. SwitchthepolarityfromPositive toNegative4. Repeat1-3withCoilPhaseC2
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Motorexcitation
TheIPMmotorissuchthattherotorisinsynchronismwiththephaseexcitation.
Theexcitationissuchthatthefluxduetothepermanentmagnetismaximizedin
synchronizationwiththerotormovement.
Theexcitationisa3phasebalancedcurrent.ThephasesequenceisA+C-B+
Att=0,theA-phasehastobeintheoppositeaxistothed-axis.Thereforewe
havetomovetheinitialpositionoftherotorby30degsuchthatthepolebe
alignedatthemiddleofA+A-
A+ A+
A-A-
B+B+
B- B-+C+A- A-
C- C-
B-
C+C+
d-axis B-
30
Maxwell modelparts
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CreateParametersforexcitations(Contd)
Thedesignpropertiespanelwilleventuallylooklike:
CreateWindings
Theterminalsaremeanttodefinetheexcitationpathsinandoutofthemodel.
Theactualexcitationisdefinedthroughthedefinitionofwindings.Awinding
needstobedefinedforeachparallelelectricalexcitationofthemotor.
Themotorisexcitedwithabalancedthreephaseconnection.Asinusoidalexcitationisapplied.Ateachtimestep,thephaseshavea120degreeshift.The
loadangleisalsoadded.
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CreateWindings(Contd)
Winding PhaseA..Fromtheprojecttree,rightmouseclickonExcitations,thenselectthemenuitemAdd W inding
1. EnterPhaseA forthename.2. SelectStrandedbecauseeachterminalhas 9 turns3. Enterwindingcurrent:Imax*sin(Omega_rad*Time+Thet). Time isthe
internalreservedvariableforthecurrenttime.
4. ClickonOK
5. RightmouseclickonthewindingPhaseA fromtheprojecttree,selectthemenuitemAdd Coils
6. Selectthe2PhaseA coils(usingtheCtrlbutton)andclickonOK
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CreateWindings(Contd)
Winding PhaseB..Fromtheprojecttree,rightmouseclickonExcitations,thenselectthemenuitemAdd W inding. Repeatthesameoperationusing:
NametheWindingPhaseBThewindingcurrentis Imax*sin(Omega_rad*Time-2*pi/3+Thet). Itisshiftby-120degreesfromPhaseA.
Selectthe2PhaseB tcoils
Winding PhaseC..Fromtheprojecttree,rightmouseclickonExcitations,thenselectthemenuitemAdd W inding. Repeatthesameoperationusing:
NametheWindingPhaseCThewindingcurrentis Imax*sin(Omega_rad*Time+2*pi/3+Thet). Itisshiftby+120degreesfromPhaseA.
Selectthe2PhaseC coils
TheprojecttreeshouldnowhavetheterminalssortedundereachWinding:
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AddCorelosscomputation
Thecorelossarenotactivatedbydefault.Ifyouwishtohavethemconsidered,
expandtheprojecttreewindow,rightmouseclickonExcitations> Set Core Loss
Selectthesteelobjects:Stator,Rotor,Rotor2andRotor3
AccepttheSetting
Note:youneedtohavethecorelossparametersdefinedinthematerialsetup
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AddBandobject
Themovingparts(rotorandpermanentmagnets)needtobeenclosedinanair
object,theband.Thiswillseparatedthemovingpartfromthefixedpartofthe
project.Somerulesapplyforthedefinitionofthebandobjectformotor
applications:
Thebandobjectmustbesomewhatlargerthantherotatingpartsinall
directions(exceptattheboundaries)
Thebandobjectshouldbeafacettedtypecylinderofwedge
Itisveryadvisabletohaveanairobjectthatenclosesallthemovingobject
insidethebandobject.Thiswillfacilitatethemeshhandlingaroundtheairgap
TocreatetheBandobject,wewillclonetheregionandadapttheparameters:
1. SelecttheobjectRegion,RightMouseclick,thenSelectEdit>Copy
2. UsetheCtrl+V keycombinaisontopastetheRegion.3. ChangethenameoftheobjectfromRegion1 toBand4. ExpandthehistorytreeoftheObject
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AddBandobject(Contd)
5. DoubleclickontheCreateLine command.Therotorradiusis80.2mm.Theinnerdiameterofthestator80.95mm.WepickthemiddleforBandobject.
Enter80.575,0,0 mminsteadof200,0,0forPoint2
6. DoubleClickontheSweep A roundAxis command.7. ChangetheNumber of Segments from5 to45 sothateachsegmentofthe
linecoversonedegree
8. LeavethematerialtoVacuum .
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AddBandobject(Contd)
WenowcreateanobjectthatenclosedthemovingobjectsinsidetheBand.SelecttheBand object,rightmouseclick,theselectthemenuitemEdit > CopyoruseCtrl-C.PasteanothercopyoftheBandobjectbyrightmouseclickingandselectingEdit> Paste orwiththeCtrl-V.AnewobjectBand1 hasbeenaddedtotheobjectlist.Expanditshistorytree,thendoubleclickontheCreateLine command
EditthePoint2:Enter80.4, 0, 0 mmThisoperationresizestheobjecttostrictlycovertherotorandthepermanent
magnets
RenametheBand1 objecttoBand_in
Note:Wewillassignthemotionafterthemeshoperationsbecausewewillhavetoaddobjectsdedicatedtothemeshinginthemovingpart
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MeshOperations
Thetransientsolverdoesnotuseadaptivemeshingbecausethiswouldrequire
torefinethemeshateverytimesteps,leadingtoveryhighcomputationtime.
UsingMeshoperations,wewilldefineadecentmeshforthefulltransient
simulation.
TheRotorisdesignedtobehighlysaturatedaroundthepermanentmagnets,
closetotheairgap.Itisrequiredtohaveagoodmeshdensityaroundthisarea.
Toachievethisrequirement,wecreateacoupleofobjectsinsidetherotor,then
meshoperationswillbeappliedtotheseobjectsinordertohaveanicemesh
aroundtheducts.
SelectthemenuitemDraw > Line orselecttheiconfromthetoolbar.1. Enter78.72,0 ,0 mmforthepositionofPoint1andhitEnter2. Enter80.2,0 ,0 mmforthepositionofPoint2andhitEntertwice3. NamethelineRotor2
Highly saturated zones
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MeshOperations(Contd)
Thelinelookslikebelow:
SelecttheRotor2 object,rightmouseclickandselectthemenuitemEdit >Sweep > A round Axis.
Entertheparametersasbelow.NotethatTheRotor objecthasbeencreatedwithanUDPwhichproducestruesurface,thereforeourmesh
objectRotor2 hastohavetruesurfaces.Asaconsequence,weenter0 forthenumberofsegments.
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MeshOperations(Contd)
ChangethematerialpropertyofRotor2 toM19_29G .Also,assignsomecolorandtransparency.
Note:sinceRotor2 isentirelyinsideRotor,wedonotneedtoapplyBooleanoperations.
Note:becauseofthefinitenumberofpixelsonthecomputersscreen,truesurfacesarerepresentedasfacettedsurfaces.Also,forthesamereason,the
objectRotor2 seemstointersectwiththeductsbutthisisnotthecase.Youcanmodifythedefaultvisualizationsettingusing:View > Visualization Setting
RepeatthesameoperationtocreatetheobjectRotor3:1. Drawalinewithdimensions:
2. SweeptherectanglearoundZaxis
3. ChangethematerialpropertytoM19_29G
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MeshOperations(Contd)
SelectthesixcoilsPhaseA1, PhaseA2,PhaseB1,PhaseB2,PhaseC1 andPhaseC2.Rightmouseclick,selectAssign Mesh Operations > Inside Selection >Length Based.
1. NametheoperationCoils2. CheckthebuttonRestrictLengthofElements
3. Enter4mm4. UncheckthebuttonRestricttheNumberofElements
5. Validate
SelectthepermanentmagnetsPM1 and PM2.Rightmouseclick,selectAssignMesh Operations > Inside Selection > Length Based .
1. NametheoperationPMs2. CheckthebuttonRestrictLengthofElements
3. Enter3mm4. UncheckthebuttonRestricttheNumberofElements
5. Validate
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MeshOperations(Contd)
SelecttheRotor.Rightmouseclick,selectAssign Mesh Operations > InsideSelection > Length Based.
1. NametheoperationRotor2. CheckthebuttonRestrictLengthofElements
3. Enter4mm4. UncheckthebuttonRestricttheNumberofElements
5. Validate
SelecttheStator.Rightmouseclick,selectAssign Mesh Operations > InsideSelection > Length Based.
1. NametheoperationStaor2. CheckthebuttonRestrictLengthofElements
3. Enter4mm4. UncheckthebuttonRestricttheNumberofElements
5. Validate
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AssignMovement
SelecttheBand object,rightmouseclickandselectthemenuitemAssignBand
IntheType tab:checktheRotate motionbuttonMakesurethattheGlobal:Z axisisselectedSelectthePositive direction
IntheData tab:Enter30 deg fortheinitialposition.TheinitialpositionofthissynchronousmotorissuchthattheAphaseisoppositetothed-
axis.
A+
A-
d-axis
30
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AssignMovement(Contd)
IntheMechanicaltab:
enter3000 rpm forthespeed.ClickOKtovalidatethesettingoftheBandobject.
RightmouseclickonModel intheProjecttree,thenselectthemenuitemSetSym metry Multiplier
Sincewemodel1/8 th ofthemotor(ourmodelspanson45),Enter8.Theforce,torquewillberescaledtotakeintoaccountthefullmodel.
SelecttheModel Depth tab.Enter83.82mm forthemotordepth.Allquantitieswillbeautomaticallyberescaledtothecorrectsize.
Acceptthesetting
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AddanAnalysisSetup
RightmouseclickonAnalysisintheProjecttreeandselectAddSolutionSetup:
1. OntheGeneral tab enterthestoptimeandthetimestep.At3000rpm,arevolutiontakes20ms(3000rpmmeans50revolutionspersecondor1/50
sforonerevolution).Toachievereasonableaccuracy,wewanttohavea
timestepevery1or2degrees.Inthisstudy,tohavefasterresults,weuse
atimestepof250 us;itcorrespondsto4.5degrees.2. Thetotalsimulationtimeissetto15ms3. OntheSave F ields tab
SelectLinearStep
ForStart,put10ms
ForStop,put15ms
ForStepTime,put250us
ClickonReplaceList
4. IntheSolver Tab,settheNonlinearresidualto1e-6.
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Solvetheproblem
Thesetupiscompleted.ChecktheprojectusingtheValidatebutton
Maxwellchecksthegeometry,excitationdefinitions,meshoperationsandso
one.ThemodelisvalidatedbutsomeWarningisdisplayedinthemessagebox:
Eddyeffectarenottakenintoaccountinourdesignwhichiswhatwe
decided
SelecttheAnalysisSetup1 intheprojecttree,rightmouseclickandselectAnalyse
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PostProcessing
Thefullsimulationtakessomeminutes.
Themeshsizeappearsintheprofileofsimulation.Todisplaytheprofile,selecttheAnalysisSetup,rightmouseclickandselectMesh Statistics.Themeshstatisticsareavailableinthecorrespondingtab
Performancecurvescanbedisplayedduringthesimulation.
Torque versus Time.SelectthemenuitemResults intheprojecttree,rightmouseclick,thenselectthemenuitemCreate Quick Report
ChooseTorqueTheTorqueuptothecurrenttimeisdisplayed.Asthesimulationcontinues,you
canupdatetheplots:rightmouseclickontheTorque Quick Report entryandselectUpdate Report
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PostProcessing(Contd)
AttheendofthesimulationtheTorquelookslikebelow
TheLoadTorque (inred)iszeroasweareinmotormode.WecanseethattherearealotofripplesintheTorque.Theratiobetweenthe
torqueandthetorqueripplesisalmost10percent.Thisisduetotheunique
structureoftheIPMmotor(InternalPermanentMagnets).Tolimittheripple,
somemanufacturersmodifyslightlytherotorshapearoundthemagnetsoradda
secondlayerofinternalmagnets.Alsothecontrolstrategyplaysabigroleintopreventingtheripples.
Thetorquevalueisaround240N.m.Thisvalueiscompatiblewithmeasurement.
Thepeaktorqueforthismotorisabout400N.m
Flux linkage versus Time .SelectthemenuitemResults intheprojecttree,rightmouseclick,thenselectthemenuitemCreate TransientReport >RectangularPlot.
0.00 5.00 10.00 15.00 20.00
Time [ms]
0.00
50.00
100.00
150.00
200.00
250.00
300.00
Y1[NewtonMeter]
Ansoft Corporation 5_Partial_Motor_TRTorque Quick Report1
Curve Info
Moving1.LoadTorque
Setup1 : Transient
Moving1.Torque
Setup1 : Transient
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PostProcessing(Contd)
Toincludethefluxlinkageforeachcoil:
1. SelectWindingintheCategory Column2. SelectFluxLinkage(PhaseA), FluxLinkage(PhaseB), FluxLinkage(PhaseC)
intheQuantity column3. SelectNew R eport4. SelectClose
0.00 5.00 10.00 15.00Time [ms]
-0.40
-0.30
-0.20
-0.10
0.00
0.10
0.20
0.30
0.40
Y1[Wb]
Ansoft Corporation 5_Partial_Motor_TRXY Plot 2
Curve Info
FluxLinkage(PhaseA)
Setup1 : Transient
FluxLinkage(PhaseB)
Setup1 : Transient
FluxLinkage(PhaseC)
Setup1 : Transient
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PostProcessing(Contd)
Induce Voltage versus Time .SelectthemenuitemResults intheprojecttree,rightmouseclick,thenselectthemenuitemCreate TransientReport >Rectangular Plot.UsethesamemethodtoplottheInducedVoltage
Thecurvesarenotreallysmooth.Thereasonisthatthetimestepistoohigh.As
theinducedvoltageisaderivedquantity,Maxwellneedstoderivethetotalflux;
thetimestepsiswaytohightohaveaccurateInducedVoltage.Ifyourerunthe
simulationwithatimestepsof50us(insteadof250us),theInducedVoltagewill
haveamorerealisticshape:
0.00 5.00 10.00 15.00Time [ms]
-500.00
-400.00
-300.00
-200.00
-100.00
0.00
100.00
200.00
300.00
400.00
500.00
Y1[V]
Ansoft Corporation 5_Partial_Motor_TRXY Plot 1
Curve Info
InducedVoltage(PhaseA)
Setup1 : Transient
InducedVoltage(PhaseB)
Setup1 : Transient
InducedVoltage(PhaseC)
Setup1 : Transient
0.00 5.00 10.00 15.00Time [ms]
-500.00
-400.00
-300.00
-200.00
-100.00
0.00
100.00
200.00
300.00
400.00
500.00
Y1[V]
Ansoft Corporation 5_Partial_Motor_TR_smallXY Plot 1
Curve Info
InducedVoltage(PhaseA)
Setup1 : Transient
InducedVoltage(PhaseB)
Setup1 : Transient
InducedVoltage(PhaseC)
Setup1 : Transient
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PostProcessing(Contd)
Plot the Mesh. Selectalltheobject,rightmouseclickandusethe Plot Meshbutton
Plot magnetic flux density.1. SelectthemenuitemView>SetSolutionContextordoubleclickonthe
Time=-1iconinthemodelerwindow
2. Selectthetime0.01s fromthepulldownmenu
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PostProcessing(Contd)
3. SelecttheStator, Stator2, Stator3, PM1 and P M2 objects.RightmouseclickandselectFields > B > Mag B
4. AccepttheSetting
5. TheBfieldat0.01sisdisplayed.
6. ChangethescalebydoubleclickingontheScaleaera
7. GototheScaleTabandenter0 forminand2.2 formax8. ClosetheWindow
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PostProcessing(Contd)
Plot magnetic flux density (Animation). Itispossibletoanimatethefields.SelectMaxwell2D>Fields>Animate.
MakesurethatthesweepvariableisTime
Selectthetimevalues
Acceptthesetting
Theanimationisdisplayedoncetheframesarecalculated.
YoucanexporttheanimationusingtheExport buttonfromtheanimationbutton
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ParametricStudy
Thesetupthathasbeensolvedwaswithaloadangleof20deg.Iftheloadangle
ismodified,thesimulationhastoberestarted.
Aparametricsweepoftheloadanglewillthereforetakealongtime.Wecan
proposetwoapproaches:
RealizeanEquivalentCircuitExtractionofthemotor.Thismethodrequires
thecombinationofparametricsweepsinmagneto-staticandthecircuit
simulatorSimplorer.Wewillnotdiscussthismethodinthiswrite-up.
Realizeaparametrictransientsimulation.Tocutthesimulationtime,the
useoftheDistributiveSolveisnecessary.Thisisthechosenmethod
ClickonOptimetrics intheProjecttree.RightmouseclickandselectthemenuitemAdd > Parametric
Theparametricsetuppanelappears
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ParametricStudy(Contd)
SelecttheAdd buttontoincludeadesignvariableinthesweep
SelectThet_deg fromthepull-downmenu:1. Enter0 deg forthefirstvalue2. Enter60 deg forthelastvalue3. Enter15 deg forthestep4. PushtheAdd button
SelecttheTabletab,theparametricrowsaredisplayed
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ParametricStudy(Contd)
SelecttheGeneralTab.Thispanelenablestheusertochangeadesignvariable.Forinstance,ifyouwishtoruntheparametricsweepwithapeak
windingcurrentof400 A,selecttheOverride button,andchangethecurrentvalue.
SelecttheCalculations Tab1. SelecttheSetup Calculations button2. UndertheCategory column,selectTorque3. UndertheQuantity column,selectMoving1.Torque4. selecttheRange Function button.5. SelecttheSpecified radiobutton6. SetecttheMath Category7. Selectavg intheFunctionpulldownmenu8. Clickonok
9. ClickonAdd Calculation10. ClickonDone
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ParametricStudy(Contd)
Thesweepsetuppanelcontainsthedesiredquantity
IntheOptionstab,youcanchoosetosavefieldsandmeshsforallthevariations
Acceptthesetup
Run the parametric sweep.Torunthesweep,selecttheParametricsetup1,rightmouseclickandselectthemenuitemAnalyse
Results.RightmouseclickonParametricsetup1,andselectView Analysis Resu lt
Alltheplotsarenowavailableforanyvariation
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COGGINGTORQUE
TheCoggingTorquecorrespondstothetorqueduetotheshapeoftheteethand
thepermanentmagnets,whenallthecoilsexcitationsare0.Thetorqueisavery
smallvalueinregardtothefullloadtorque.Itscomputationisverysensitiveto
themesh,asitsvalueisinthesameorderofmagnitudeofthemeshnoise.
TocomputeaccuratelythecoggingTorque,onecouldsolveaparametricsweep
inMagnetostatic(theinputparameterbeingtheanglebetweenrotorandstator).
Thismethodwillnotleadtoexcellentresultsastheerrorduetothemeshwillbedifferentforeachposition(themeshwillchangeforeveryrow).
Thepreferredmethodistheuseofthetransientsolverwithmotion:
Wewillmovetherotoratthespeedof1deg/s
ThemeshwillremainunchangedforallthepositionsthankstotheBand
object:themeshinsidetheBandobjectwillrotatewiththerotor
Eachtimestepwillbeindependentoftheother
Theadaptivemeshwillnotbeusedthereforethesimulationtimewillbe
shorter
Savetheproject.ClickontheMaxwelldesign5_Partial_motor_TR ,rightmouseclickandselectCopy.
Clickontheprojectname,rightmouseclickandselectPaste.Changethecopied
designto6_Partial_motor_CT
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CreationofanairObject
WederivethesetupforthecoggingtorquecalculationfromtheFullloadsetup.
Wewillchangethespeed,theexcitationsandsomemeshingoperations.
Sincethemeshhastobewelldefinedintheairgap,wewilladdanobjectsothat
wehaveenoughlayersofelement:
1. CopyandPastetheObjectBand_in
2. RenametheobjectBand_in1intoBand_out.
3. ExpandthehistorytreeofBand_outandchangetheCreateLinecommand:
Replace80.4,0,0by80.75,0,0mm
Thiscreateathirdlayerintheairgap
Stator
Band_out
Band
Band_in
Rotor2
Rotor3
Rotor
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Increasethesegmentationofairobjects
Forthedynamicanalysis,theojectsBand,Band_in hadonesegmenteverydegre.Inordertoreducemesherror,wereducethespanofeachsegment.
ExpandthehistorytreeoftheobjectsBand,Band_in andBand_out:1. DoubleclickontheSweepAroundAxis commandoftheBand object
2. Changethenumberofsegmentsfrom 45 to1353. Repeat1-2fortheobjectsBand_in, Band_out
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MeshingOperations
WeneedtoreassigntheBand.Expandtheprojecttreeofthecurrentdesign,anddeletetheMotionSetup1
SelecttheObjectBand,rightmouseclick,andselectAssign Band
EnterthefollowingparametersfortheMotionSetup
IntheTypeTab,forMotionType:Rotation around Z axisLeavetheData tabunchangedIntheMechanical tab ,enter1 deg_per_secAccepttheSetting
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MeshingOperations
Wealsoneedtochangethemeshingoperations.Themeshdensitythatwas
goodenoughtocomputethefullloadtorquewontbeaccurateenoughforthecoggingtorque
Expandtheprojecttree,andunderMeshoperations,edittheMeshingoperations
Rotor,Stator:Changethemaximumlengthfrom4mm to3mm
SelecttheobjectsRotor,Rotor2 ,Rotor3 andStator.RightmouseclickandselectAssignMeshOperation>SurfaceApproximation
NamethemeshingoperationSA_Rotor_Stator
Settheminimumnormaldeviationto1deg
Ignoretheothersettings
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7/30/2019 3856 Motor Maxwell2D
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7/30/2019 3856 Motor Maxwell2D
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TopicMotorApplicationNote
Analyse
Fromtheprojecttree,rightmouseclickonSetup1,andselectAnalyse.Ittakesacoupleofminutestosolve
Fromtheprojecttree,rightmouseclickonResults,andselectCreate TransientReport > Rectangular plot. TheTracewindowpopsup
FromtheCategory columnselectTorqueFromtheQuantity column,selectMoving1.TorqueSelectNew R eportSelectClose
TheTorquetraceappears.Asexpected,thecoggingtorqueisperiodical.The
peak value is about