Influence of speed and flux estimation by Luenberger observer on IM drive with DTC

The direct torque control (DTC) strategy is one of the most performance methods for induction machine (IM) drive torque control. The controlled stator magnetic flux and torque cannot be easily measured and therefore must be calculated using an IM mathematical model. This paper examines the impact of the replacement the original voltage IM model by Luenberger observer on the drive performance. As the original model requires only voltage and current, the observer is implemented in such a way that the same input variables can be used. The models are created and tests are carried out experimentally employing the dSPACE platform on induction motor of power 5.5 kW. The experimental results indicate better performance of the control strategy based on Luenberger observer.