A New Sensorless DTC-SVM Control Method for DFIM Drives

This paper presents an improved method for calculating the rotor position and speed of a doubly fed induction machine (DFIM). The rotor position is estimated by means of measured stator and rotor voltages and currents, without need to estimation of the stator flux. The proposed algorithm is simple and effective and, direct estimation of the stator flux is not required. One of the most important advantages of this scheme is that the calculations do not use any approximation. This method is robust against variations of stator and rotor resistances and only error in estimation of the machine mutual inductance can somewhat influence that. This approach does not need to any initial data of machine. Simulation results validate effectiveness of the proposed sensorless space vector modulation direct torque control of DFIM under steady-state and dynamic conditions.