Efficient Technique for Analyzing Non-Uniform Transformer Windings

Mohamed Mostafa Saied

Abstract

This paper addresses the electromagnetic transients and the frequency characteristics of non-uniform transformer windings exhibiting inter-winding mutual circuit parameters. The dependence of the winding inductances and capacitances on the location along the winding is incorporated in the governing Kirchhoff’s voltage and current equations with the voltages and currents as unknowns. These unknowns will then be determined through the application of algebraic solution techniques in order to get closed-form analytical voltage and current expressions in the s-domain. These expressions can be used for investigating the winding’s frequency response and its input impedance as well as exploring possible resonance phenomena. Moreover, the expressions will be numerically Laplace-inverted using the software Mathematica. The result will be the time response of the winding’s voltages and currents. The results of several case studies will be presented and discussed.