For the correct operation of a field oriented control drive, parameters of the induction motor should be fully defined. To obtain the parameters a dc step voltage response method is used. A dc voltage step is applied to the stator winding and the stator current is recorded. Four samples of the latter are needed to calculate the stator resistance, the stator self-inductance, the rotor time constant, and the linkage constant. The high accuracy of these parameters is achieved by using an iteration algorithm. The small number of iterations (5-10) gives accuracy to a fraction of a percent