Feedback linearizing control of induction motor considering magnetic saturation effects

This paper presents a input-output Feedback Linearization (FL) control technique for rotating Induction Motors (IM), which takes into consideration the magnetic saturation of the iron core. Starting from a new formulation of the IM dynamic model, taking into consideration the magnetic saturation, expressed in a space-state form in the rotor flux oriented reference frame, the corresponding FL technique has been developed. To this aim, a particular care has been given to the choice of the non-linear functions interpolating the magnetic parameters vs the rotor magnetizing current curves and the corresponding magnetic characteristic. The proposed FL technique has been tested experimentally on a suitably developed test set-up and compared, under the same bandwidths of the speed and flux closed loops, with both the FL technique not taking into consideration the magnetic saturation and with the industrial standard in terms of high performance control of the IM: Field Oriented Control (FOC).