New method for calculation of series capacitance for transient analysis of windings

The paper presents an analytical procedure which enables a quick and mathematically rigorous evaluation of the series capacitance of any winding (transformer, reactor or magnet). The method is based on the application of the equations for solving a uniform lumped parameter ladder circuit of any size (from one up to an infinite number of pis) and for any terminal conditions. They are applied here on a specific and complex electrical circuit formed of intra- and inter-coil turn-to-turn capacitances of the coil sections. The derived formulae can be directly used in cases where the coil insulation characteristics do not vary along a winding.