METHOD FOR DETERMINING THE ROTATIONAL SPEED OF THE TURBOCHARGER OF AN INTERNAL COMBUSTION ENGINE OF A MOTOR VEHICLE

Method for determining the rotational speed of the turbocharger of an internal combustion engine of a motor vehicle, optionally equipped with at least one high-pressure exhaust gas partial recirculation circuit tapped between the exhaust manifold and the intake manifold. The method comprises the following steps: an accessible measurements vector is determined comprising the measurement of the pressure before the turbine, the pressure in the intake manifold and optionally the pressure after the EGR heat exchanger, the difference is determined between the accessible measurements vector and the corresponding accessible measurements vector resulting from an observer, a vector of time derivatives of the observed variables is determined as a function of the difference between the accessible measurements vector and the corresponding accessible measurements vector resulting from the observer, and a vector of the observed variables is determined by integration of the vector of time derivatives of the observed variables, the vector of the observed variables comprising observed values corresponding to the values of the accessible measurements vector and the rotational speed of the turbocharger.