Robust Speed Sensorless Control of Doubly-Fed Induction Machine Based on Input-Output Feedback Linearization Control Using a Sliding-Mode Observer

In this paper a nonlinear controller is presented for doubly-fed induction machine (DFIM) drives. The nonlinear controller is designed based on input-output feedback linearization control technique, combined with sliding-mode observer. Using the fifth order model of induction machine in fixed stator d ,q axis reference frames with stator current and rotor flux components as state variables. The nonlinear controller can perfectly track the torque and flux reference signals inspite of stator and rotor resistance variations. In order to make the drive system capable of operating in the motoring and generating modes below and above synchronous speed, two level SVM-PWM back-to-back voltage source inverters are employed in the rotor circuit. Computer simulation results obtained, confirm the effectiveness and validity of the proposed control approach.