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. |