Robust speed control of induction motors: application to a benchmark example

A non-linear robust output feedback control is designed for a sixth-order m odel of an induction motor. The control uses only measurement of the rotor position and stator currents. It contains two observers, a second-order obs erver to estimate the rotor flux from the stator current and a third-order high-gain observer to estimate the rotor speed and acceleration from its po sition. The control is robust to uncertainties in the rotor and stator resi stances, and a bounded time-varying load torque. It guarantees that the spe ed tracking error can be made arbitrarily small by choice of certain design parameters. Moreover, when the speed reference and load torque and constan t, it ensures asymptotic regulation. The controller is applied, via simulat ion, to a benchmark example. Copyright (C) 2000 John Wiley & Sons, Ltd.