earticle

영어

This paper deals with high performance speed control approach using direct flux and torque control for the induction motor (IM). The closed loop scheme of the drive utilizes the fuzzy logic controllers both in speed and electromagnetic torque control loops. Due to the drawbacks of the sensors, an algorithm is evolved to reconstruct the IM fluxes and electromagnetic torque. In fact, based on the model of the IM, the observed stator currents and IM fluxes are simultaneously obtained based on full order Luenberger observer. The observed stator currents and IM fluxes are adversely affected by rotor speed feedback signal and stator resistance variations due to temperature and frequency changes. To improve the performance of the overall system, the rotor speed and stator resistance are both estimated in such away to assume the overall stability of the state observer based on Lyaponov criterion. Digital simulation results are presented to show the improvement in performance of the proposed method.