High performance induction motor speed control based on extended state observer with stator fluxes model

A new approach for induction motor speed and flux tracking control is proposed in this paper. The unknown load torque is observed using the extended state observer (ESO), a kind of observer with non-smooth nonlinear feedback. The speed controller is designed compensating the load disturbance by the ESO. The torque and flux controller, which are utilized to achieve torque and flux tracking objective and hold the decoupling characteristic, are designed by direct feedback linearization method. All the work is based upon the fifth-order motor model using stator fluxes as state variables, with an improved stator flux observer. Simulation results illustrate the essential features of the presented method.