Application of MRAS Observer in Induction Motor Drive with Direct Torque Control

Abstract

The PhD thesis describes model reference adaptive system speed observers for a speed sensorless induction motor drive with direct torque control methods. A mathematical description of components in control system such as induction motor, frequency converter is given. Theoretical analyses and assumptions of the direct torque control and the model reference adaptive system are presented. Simulations are used to verify the assumptions and choose the suitable direct torque control method and model reference adaptive system speed observer. A description of laboratory workplace is given. Fuzzy logic is applied in the speed controller of control structures. Verification the application of the model reference adaptive system in sensorless induction motor drive with direct torque control is experimentally carried out in various conditions. Advantages and disadvantages of the direct torque control methods and the model reference adaptive system speed observer, and the role of fuzzy logic are concluded.