New approach to the analysis of impulse voltage distribution in transformer windings

Abstract

A new calculation method for the analysis of transient voltage phenomena in HV power transformers is presented. Consideration is given to the electric, magnetic and current fields in the windings. An equivalent circuit is derived; this consists in the connection of two networks, one magnetic the other electric, whose components with their numerical values are deduced directly from the geometry of the transformer and from its electrical parameters. Application of the ensuing mathematical model to a real case of a 132 kV, 50,000 kVa power transformer is discussed.