Efficiency optimization for sensorless induction motor controlled by MRAS based hybrid FOC-DTC strategy

The Field Oriented Control (FOC) and the Direct Torque Control (DTC) are the well-known control strategies in the modern AC systems nowadays. However, both of them have a number of limits, such as the dependence on machine parameters of the vector control and the high ripples of DTC. This work presents a hybrid control strategy for induction motor (IM) based on the combining of the two techniques in order to benefit from their advantages and achieve high performance control. Besides, a Model Reference Adaptive System (MRAS) observer will be used for speed estimation to improve the reliability and decrease the cost of the control system. Furthermore, the IM energy optimization will be treated as the second objective of this paper. A proposed model based strategy will be used for loss minimization. This strategy bases on online adjusting of the rotor flux magnitude reference and choosing an optimal value for each applied load torque. The proposed algorithm will be investigated by simulation and experimental implementation by using Matlab/Simulink with real time interface (RTI) based on dSpace 1104 board.