State variables controller design for vibrations suppression in electric vehicles

In this paper, the mechanical model of electric vehicles is presented to study low frequency speed oscillations that can arise in some working conditions. To reduce and possibly to eliminate these oscillations, a state space regulator is proposed. The state variables used by the regulator are estimated by a Luenberger observer. The regulator and the observer constitute the vibrations suppression module (VSM), which is added to the overall induction motor drive controller. Complete simulation results are reported to show the electric vehicle overall performance.