On Determination of Leakage Inductances of Transformer Windings

Abstract

Abstract—When designing a transformer structure and numerical simulation, it is needed to calculate the parameters of an equivalent circuit. One of the most important parameters is the leakage inductance of two windings or of their parts, the calculation of which can be relatively easily performed solely for simple cases of equal high windings. For more complex configurations, it is necessary to apply special methods, which are developed mainly for calculating the leakage inductances of high-power network transformers. Among these methods, one can distinguish the method of average geometric distances, methods based on the analytical solution of Maxwell’s equations in a two-dimensional axisymmetric statement, and the numerical finite elements method. In this work, these methods are used to calculate the leakage inductances of small-sized transformers with winding configurations typical for voltage transformers of inductive type and station service voltage transformers. The accuracy of methods is estimated by comparing the calculation results with experiment. The description of the experimental setup is presented, the general characteristics of calculation methods are given, and the results of comparison of calculated and experimental values of leakage inductances are analyzed.