A speed sensorless vector control system of induction motors using current observer and taking into account iron loss

This paper presents a new sensorless vector control system for general-purpose induction motors by taking into account iron loss, in which a current-observer-based method and the model reference adaptive system (MRAS) theory are applied. Since the current observer is constructed in a synchronously rotating reference frame with respect to the current model and the parallel exiting circuit of iron loss resistance is used, the proposed system is simple and the compensation of iron loss is directly realized while calculating rotor fluxes and slip frequency. The accuracies of estimated torque and speed are improved. The effectiveness of the proposed system has been verified by digital simulation and experimentation.