Sensorless rotor position based on MRAS observer for doubly fed induction generator

In this paper is proposed the application of the model reference adaptive system (MRAS) observer for rotor position estimation for controlling the doubly fed induction generator (DFIG), operating in balanced and unbalanced voltage sags. The rotor position is required for the transformation of variables. A MRAS observer based on current and voltage models performs the rotor position calculus. To analyze and validate the MRAS observer, the stator power is controlled from PI controllers. Experimental tests are performed and analyzed for the same generator under balanced and unbalanced voltage sag.