Sensorless control of induction motor using modified MRAS

Abstract

he paper describes methods of the speed estimation for vector controlled induction motor without speed sensor. A short analysis of the selected methods of the speed estimation has been made. The Model Reference Adaptive System method (MRAS) is chosen for its good tracking capability and moderate demands on the DSP unit. The paper contains mathematical description of the MRAS. The selected modifications of the MRAS for improvement applicable range of the speed are also discussed. Simulation and experimental results of the vector controlled induction motor drive with speed estimation are shown to present features of the MRAS speed estimators.