This paper deals with the parameters estimation of a three-phase squirrel cage induction motor integrated in an electric drive system where minimum experimental data are available. For this purpose an experimental test of direct-on-line motor starting under load is carried out and the time variations of phase voltage, current and speed are recorded. Using these values along with the stator phase resistance measured separately in dc, a numerical treatment procedure of the experimental data was developed and other missing parameters of the machine were determined (e.g. magnetization inductance, rotor circuit resistance referred to stator, stator and rotor referred to stator leakage inductances, inertia moment and friction factor). The numerical procedure includes analytical calculations and an inverse problem solving programme that uses optimization algorithms developed under Matlab-Simulink environment.

Keywords: Induction machine, Parameters estimation, Electrical drive system