New adaptive flux observer of induction motor for wide speed range motor drives

A flux observer of an induction motor with a parameter adaptive scheme is proposed. The parameters identified adaptively are stator and rotor resistance, which vary with motor temperature. The stability of the proposed adaptive flux observer is proved using Lyapunov's theorem. The robustness of the induction motor drive system with the proposed flux observer is shown. The adaptive scheme can also be applied to estimate motor speed without speed sensors.>