Modified integrator for voltage model flux estimation of induction motors

This paper deals with voltage model flux estimators for speed sensorless induction motor drives. In order to eliminate the drift problems, the pure integrator of the voltage model is replaced with a first-order low-pass filter, and the error due to this replacement is compensated. An effective way to calculate the compensation is presented, and the compensation is carried out before the low-pass filtering, in order to avoid dynamic errors.