Improved twelve sectors DTC strategy of induction motor drive using Backstepping speed controller and P-MRAS stator resistance identification-design and validation

Abstract

The Direct Torque Control (DTC) was previously designed to achieve high performance of induction motor (IM) by accurately and independently controlling its flux and torque. However, this classical DTC generates several disadvantages such as strong fluctuations in the torque and stator flux as well as quite significant switching losses. For these reasons, many modern techniques have been proposed in the literature to improve it. On the other hand, as the inadequacy of the parameters seriously affects the efficiency and stability of the induction motor, it is paramount to accurately estimate the stator resistance, for this, robust observers are necessary suggested to be employed. This paper proposes developed structure of DTC strategy using twelve sectors combined with Backstepping speed regulator for the external loop and robust model reference adaptive system based on active power principle to estimate the stator resistance. In addition, several simulations under Matlab/Simulink and experiment results using the dSPACE DS1104 board are discussed to confirm improvements in control and speed estimation.