Adaptive Partial-State Feedback Control for Induction Motors

In this paper, a nonlinear adaptive dynamic controller is designed for velocity and flux magnitude tracking of induction motors. The control design is a partial-state feed-back design that utilizes rotor velocity and stator current measurements. Rotor position and flux measurements are not utilized for feedback. Furthermore, an adaptive approach is followed to compensate for uncertainty in the mechanical parameters (inertia, friction, and load torque) and the rotor resistance. The only information required about these parameters is a lower bound on the rotor resistance. The designed controller has dynamic order 12 and achieves asymptotic tracking of the rotor velocity trajectory and bounded tracking of the flux magnitude trajectory. Under a persistency of excitation condition, asymptotic tracking of the flux magnitude trajectory is also obtained.