ndthecoreloss(magnetichysteresisloss,eddycurrentloss)areneglected.()Theinfluencefactorsincludingtemperature,frequencyetc.onparametersofmotorarenotconsidered.Mechanicalmovementequationofelectricmachineisfixedandwon’tchangewiththecoordinatetransformation.BLDCMmechanicalmovementequationisasfollows:Te-Tl=Jdtd+B()whereTeiselectromagnetictorque,TLisloadtorque,Jisrotorandloadinertia,Bisfrictioncoefficient,ωisrotatingspeedofBLDCM.Takethethree-phasestatorvoltageasthestatevariable.Itsvoltagebalanceequationcanbeexpressedas():UaRaiaLaLabLaciaeaUb=Rbib+dtdLbaLbLbcib+eb()UcRcicLcaLcbLcicecBecausetherotorispermanent-magnet,La,Lb,Lc,Lab,Lba,Lac,Lca,Lbc,Lcb,canbeconsideredasconstants,then,Ra=Rb=Rc=RsLa=Lb=Lc=LLab=Lba=Lac=Lca=Lbc=Lcb=M()ia+ib+ic=Therefore,weobtainthePMBLDCMvoltageequationwhichisshownin():UaRsiaL-MiaeaUb=Rsib+L-Mdtdib+eb()UcRsicL-MicecThetopologyofBLDCMmodelisobtainedfrom()andshowninFig..Fig.TopologyofBLDCMmodelSo