Electric Field Distribution around Contaminating Wire Particles Inside Gas Insulated Bus Duct

Abstract

The presence of metallic contaminating particles lowered the dielectric strength of the gas sharply. The determination of the insulation breakdown inside gas insulated bus duct requires the knowledge of the field distribution inside it. Finite Element Method (FEM) has been used throughout this work, for its favorable accuracy, to calculate the electric field distribution inside the bus duct. In this paper, the electrostatic modeling of gas insulated bus duct (GIBD) with particle contamination is studied. The effect of particle length, hemi-spherical radius and ratio (L/r) on the electric field values is presented. The effect of the dielectric coating of the inner surface of enclosure, is presented and discussed. Multi-contaminating fixed particles are considered in this work and the electric field distribution in this case is presented. The effect of particle length and radius of middle fixed particle of multi contaminating particles on the electric field values are also studied. Electric field distribution around disc-spacer with and without an earthed particle contamination is presented and discussed. Finally, the effect of distance between particle and spacer on the electric field values is also studied.