Analytical and Numerical Estimation of the Leakage Reactance in the Sandwich Winding Transformers

Sandwich winding transformers provide easy control over the leakage impedance and it is widely used in low voltage applications which include converters in power electronics, and electronic circuits. Leakage reactance is one of the major parameters in the designing of the sandwich winding transformers as voltage regulation and short circuit current mainly rely on the leakage reactance of the transformer. In the literature, there are many available formulas for the calculation of the leakage reactance in the concentric winding transformers. In this work, leakage reactance in the sandwich winding transformers is calculating by using an analytical technique. The analytical formula is derived from the available equations for the calculation of the leakage reactance in the concentric winding transformers. The analytical results are also verified by using a two-dimensional finite element method.