H- infinity disturbance attenuation control of induction motor

State-space H-co approach is employed to attenuate norm-bounded disturbance s with time-varying coefficient in uncertain linear systems. The proposed m ethod is applied to the feedback linearization control of non-linear induct ion motors (Ortego et al., 1998) subject to unknown time-varying rotor resi stance and load torque. Robust stability and tracking performances of rotor speed and flux amplitude are guaranteed by solving Riccati inequalities. W hen the flux cannot be measured, a simple observer is added and the observe r error is dealt with as an external disturbance. The method is also applie d to position tracking. Simulation results based on benchmark tests demonst rate the efficiency of the proposed approach. Copyright (C) 2000 John Wiley & Sons, Ltd.