A novel observer-based flux estimation for speed sensorless DFO control of induction machine

摘要

This article proposes a novel closed-loop rotor flux observer to estimate the rotor flux and velocity of induction motors. With the proposed algorithm, the accuracy of the estimated flux is guaranteed when the estimated stator current converges to its actual one. With the help of the estimated rotor flux magnitude and angle information, the direct rotor field orientation vector control can be implemented, and the rotor speed can be derived. Compared with the traditional Luenberger observer, the salient advantage of the proposed observer-based flux estimation is that the flux estimation is independent of either the estimated speed error or rotor time constant deviation. The validity of the proposed method is verified by intensive digital simulation results.