The Algorithm for Online Stator Resistance Identification of an AC Induction Motor

This paper presents novel algorithm for stator resistance identification. This algorithm operates online and requires no external excitation. The identification is realized from steady state operation. This partially limits the employment of proposed algorithm for drives which are designed to run mostly in steady state, it means for the applications where the load changes mostly slowly. The presented method uses the fact that the inductances are during operation of vector control algorithm constant when the flux level is kept constant. Both, the stator and rotor resistances are varying with time due to changes in temperature. These changes are very slow. The algorithm is not computationally intensive which makes it suitable for real time implementation in reasonable hardware