The purpose of this paper is to present a new methodology to control current-fed induction motor. This approach results from a combination of the differential flatness properties and the monovariable Generalized Predictive Control with Multiple Reference Model (GPC/MRM) algorithm. The chosen outputs: the rotor speed and the square of the rotor flux modulus, with respect to the motor modeling, lead to a flat system. This therefore allows to track speed and flux nominal trajectories respecting the motor's constraints. Simulation results are given in the case of nominal and mismatched parameters on the complete nonlinear model.