Influence of Interlaminar Flux between Cores on Iron Loss in Three-legged Wound Transformer Core

Abstract

A three-legged wound transformer core is composed of two inner cores and one outer core, and the interlaminar flux occurs between inner and outer cores in three-phase excitations. Past analyses of magnetic properties of three-legged wound transformer cores were based on the model of independent magnetic paths in the individual core, and did not factor the influence of interlaminar flux in the calculations. This paper shows experimental results of interlaminar flux between cores and iron loss increase caused by that. Results show that the interlaminar flux between the inner and outer core increases the local iron loss in the boundary region of the inner and outer core.