Calculation of Electrical Parameters for Studies on Propagation Characteristic of PD along Transformer Winding

Abstract

In order to investigate the propagation of partial discharge pulses in transformer winding, the simulation model of a 180 turns continuous disc type transformer winding based on multi-conductor transmission line (MTL) theory is constructed. According to the symmetry of windings, a 2D equivalent finite element model is set up under ANSYS environment. A modified method is proposed to calculate the K matrix that decrease distinctly calculation cost without loss of accuracy. For the evaluation of L and R parameter of transformer with iron core in MHz frequency area, the skin effect of conductors and iron area is taken into consideration. The frequency-dependent parameters are calculated first by time harmonic magnetic field analysis. The proposed methods of calculating parameters are helpful to research on propagation characteristic of partial discharge (PD) pulses in electric equipments.