IEEETRANSACTIONSONINDUSTRYAPPLICATIONS,VOL.43,NO.2,MARCH/APRIL2007485BackEMFEstimation-BasedSensorlessControlofPMSM:RobustnessWithRespecttoMeasurementErrorsandInverterIrregularitiesBabakNahid-Mobarakeh,Member,IEEE,FaridMeibody-Tabar,Member,IEEE,andFrançois-MichelSargosAbstract—Inthispaper,theinfluenceofmeasurementerrorsandinverterirregularitiesontheperformanceofsensorlesscon-trolisstudied.Thecontrolalgorithmisbasedontheback-electromotive-forceestimationwhoserobustnesswithrespecttothemachineparameteruncertaintieshasbeenalreadystudiedbysupposingthatthecurrentmeasurementsandthepowerstageareideal.Here,thesehypothesesareremovedanditisshown,analyticallyandexperimentally,thatthecontrolperformancesatlowspeedsarehighlyaffectedbytheimperfectionoftheelectroniccomponents.Finally,theinterestofonlinestatorresistanceestima-tionimprovingthesensorlesscontrolperformancesinspiteoftheabovedisturbancesispresented.IndexTerms—Nonlinearsystems,permanent-magnetsynchro-nousmachines(PMSMs),robustness,sensorlesscontrol.NOMENCLATURERsStatorresistance.LStatorinductance.ΨfMagnetfluxlinkagethroughthestatorwindings.PNumberofpolepairs.JInertiacoefficient.KfTorquecoefficient(Kf=PΨf).U0DCsourcevoltage.iStatorcurrent.IsStatorcurrentmodule.νStatorvoltage.eBackelectromotiveforce(EMF).ΩRotorangularspeed.ΩsAngularspeedofδ−γframe.ωsStatorelectricalpulsation(ωs=PΩs).θRotorposition.ϑPositionofδ−γframe.ϕRotorpositionerror(ϕ=ϑ−θ).ΓLLoadtorque.PaperMSDAD-06-16,presentedatthe2004IndustryApplicationsSocietyAnnualMeeting,Seattle,WA,October3–7,andapprovedforpublicationintheIEEETRANSACTIONSONINDUSTRYAPPLICATIONSbytheIndustrialAutomationandControlCommitteeoftheIEEEIndustryApplicationsSociety.ManuscriptsubmittedforreviewOctober15,2004andreleasedforpublicationNovember6,2006.ThisworkwassupportedbytheGroupedeRechercheenElectroniqueetenElectrotechniquedeNancy(GREEN),CNRSUMR7037,InstitutNationalPolytechniquedeLorraine(INPL).TheauthorsarewiththeGroupedeRechercheenElectroniqueetenElectrotechniquedeNancy(GREEN),CNRSUMR7037,InstitutNationalPolytechniquedeLorraine(INPL),54516Vandoeuvre-Lès-Nancy,France(e-mail:babak.nahid@ieee.org;meibody@ensem.inpl-nancy.fr).DigitalObjectIdentifier10.1109/TIA.2006.889826Subscriptsα,βStationaryframecomponents.d,qSynchronousframecomponents.δ,γControlframecomponents.Superscripts∧Estimatedquantities.∼Estimationerrorquantities.I.INTRODUCTIONVECTORCONTROLhasbecomeastandardincontrolofpermanent-magnetsynchronousmachines(PMSMs),butitrequirespreciseinformationontherotorposition.Thecostofmechanicalsensorsandthedifficultytoplacethemencourageresearcherstoavoidtheiruseandtostudythemechanicalsensorlesscontrol[3]–[9].Forthenonsalient-polePMSM,thetechniquesbasedontheback-electromotive-force(EMF)esti-mationarethesimplestandthemostfrequent.Inthisapproach,thecomponentsofthebackEMFvectorareestimatedusingtheelectricalequationsofthemachine.ThemechanicalvariablesarethendeducedfromtheestimatedcomponentsofthebackEMF.However,inspiteofitssimplicity,thisapproachissensi-tivetothemachinemodelandparameteruncertainties[6]–[8],totheinverterirregularitiesandtothemeasurementerrors.TherobustnessofthebackEMFestimation-basedsensorlesscontroltechniquesisstudiedin[8]bytheauthors.Itisshownthatthesemethodsaresensitivewithrespecttothemotorparameteruncertaintiesandparticularlytothestatorresistancevariations.A...
