MODELING OF THE SATURATED LEAKAGE REACTANCE OF INDUCTION-MOTORS AS A TIME-VARYING PARAMETER FOR TRANSIENT COMPUTATIONS

A procedure has been developed for incorporating the saturated leakage reactance of induction motors into starting transient performance evaluation. An empirical formula has been provided for simulating the envelope of the transient current in terms of time. This faciliated to express the transient rms stator winding current in terms of time. Then saturated leakage reactance is expressed in terms of the transient rms stator winding current, which in turn, made it possible to express the leakage reactance as a time varying parameter. All types of slot openings, i.e., closed slots, semi closed slots and open slots are considered separately. Transient performance of a machine having closed slots on the rotor and semi closed slots on the stator is evaluated using the approach described in this article and the effect of leakage path saturation is demonstrated.