Mathematical Modeling of the Equivalent Damper Winding of a Salient-Pole Synchronous Machine

Abstract

A procedure for determining the parameters of the equivalent damper winding under rotor slipping conditions is considered. The procedure is based on using the electromagnetic parameters of all physical components of a real damper winding taking into account the current displacement effects. The procedure can be used in analyzing the startup modes of synchronous motors with adapting the calculated parameters to continuous change of slipping. It is also proposed to determine the adequate parameters of the equivalent damper winding for studying the transients with synchronous motion of the rotor. To this end, the mathematical model of a synchronous machine with a distributed (real) damper winding is used. It is shown that the transients in the synchronous generator with the equivalent damper winding and in the generator with the distributed damper winding triggered by a three-phase short-circuit fault from the initial no-load mode are characterized by almost identical oscillograms. The oscillograms of a similar transient with the equivalent damper winding designed for operation in an asynchronous mode are characterized by lower initial amplitudes of currents through the windings and a lower electromagnetic torque amplitude.