Wide speed range flux estimator for direct vector controlled induction motor

In direct vector control method of induction motor, flux estimation is done either by using current model or by using voltage model. The voltage model flux estimator is suitable only for high speed operation whereas the current model flux estimator is suitable only for low speed operation. A hybrid estimator ideal for wide speed range is proposed using a speed dependent function. The studied control system is based on the rotor flux oriented method. The proposal is validated by simulation studies and it is shown that the hybrid estimator improves the accuracy of flux estimation.