A Mutual MRAS Identification Scheme for Posit ion Sensorless Field Orientation Control of Induction ]-Machines

A mutual Model Refereme Adaptive System, (MRAS) con,tainmg two m,odeBs is proposed to i m plem:ent a! position! sensorless Field Orientat ion Control (FOC) of a n in8duction, mack,in,e. For the rotor speed estim,ation,, one m#odel is used as a reference model and m o t h e r is the ad@stahk m.odel. Pure integration and stator leakage indu.ctance are rem,oved f r o m th,e refere n w model, re.su.ltinjg inl robust perform,n.nce in, low and high speed ro,n,ges. For the stator resistance identification,, the tuio m,odels switch th,eir roles, that is, the referenee m#odel becom,es th,e n.djustable model a,nd the ad,justable m,odel becom,es the referenxe model. Assum,ing a, brief stable rotor speed in,terval, the s tator resistance can he tracked vemj well. To fur ther improve tRe est ima t ion accuracy of rotor speed a,nd stator resis a, simple on#-lin,e rotor tim,e con,stan,t identifieat i s mutual MRAS .s m e i s a cost eflecfor posi t ion sen,sorless variable speed i m plementation,. Com,puter s i m u h t i o n s and experimental results are given, to shom i ts effectiveness.