Use of adaptive notch filtering for accurate speed holding in a sensorless induction motor drive

This paper presents a high accuracy, sensorless, induction motor speed control scheme. It is based on a typical V/F drive and uses an adaptive notch filter to provide real-time speed measurement and feedback. This facilitates precise steady state speed control of an induction motor over a wide speed range. The implementation requires only knowledge of the number of rotor slots and does not require resistance or inductance parameters