Time-domain analysis of the invertor-fed induction motor

The paper investigates induction motors running at constant speed and fed by invertors. It is based on linear 2-axis theory, and shows that an exact equivalent circuit can be drawn which includes a back e.m.f. opposed to the applied voltage, as in the synchronous motor. A rigorous analysis leads to explicit expressions in forms suitable for computation of the axis currents as time functions; samples of computed curves are given. In addition, a short approximate method is given for deriving the axis currents as time functions, including the current at commutation. Comparisons with experiments are included.