ABSTRACT
In this chapter, the author explores the task of development of a mathematical model of the power transformer in a cylindrical three-dimensional coordinate system. Physical structure of the power transformer is visualized to consist of multi-winding layers spread between the inner ferromagnetic material core and the outer grounded tank. An exact equivalent circuit model for the multi-layer winding transformer is presented which took into consideration the three space dimensional variations of all electromagnetic field components coupled with the fact of sizable separation among the in-winding layers. The response model identifies parametric conditions of transformer operation in the domain under short-circuit and open-circuit conditions, when subjected to the program of intense lightning surge. It is of special interest to see reflection of the transformer induced voltage due to lightning surge on the other winding layers, in the form of the equivalent circuit representation.
