This study presents a practical approach to reduce in tern of magnetic loss, core vibration, noise level, and magnetostriction variation for single-phase transformer by using constructed a model of magnetic circuit. In this paper, it is indicated that there is two kind of model which including half-turn (HT) and normal type (NT) of winding structure which will be induced core in magnetic flux variations. First, this study has constructed a useful way to analyze the magnetic core in core loss and magnetic flux variation by using finite element analysis (FEA). The half-turn structure of winding effect is present changing the winding in order to leading electromagnetic variation was taken out from the different sides of the core. The result is an additional half-turn in one of the core windows in a single-phase transformer, which can create over fluxing of the core leading to excessive losses and temperature rises. This paper presents a methodology with magnetic circuit to analyze the half-turn effect in transformer. The experimental measurement and FEA results between 60 Hz to 3 kHz, comparisons of different core magnetic circuits of transformer in electromagnetic and magnetic flux variation, were analyzed.