Electric field computation of epoxy- nano and micro composite conical spacer in a gas insulated busduct

Abstract

In gas insulated systems, the breakdown strength of SF6 gas is badly affected by locally enhanced electric fields. Polymer nano-composites are the recent advancements in alternatives for the existing insulating materials. Polymer nano- and micro-composite mixture exhibits excellent electrical, thermal, and mechanical properties. In GIS, the reliability can be enhanced up to a great extent with epoxy resin along with polymer nano- and micro-filler mixture as dielectric coating material. The addition of nano- and micro-filler can further enhance insulation properties of epoxy resin. In this paper, the electric field distribution and calculation of relative permittivity of a single-phase common enclosure for an optimized design of GIS with nano-composites are carried out. Inorganic nano-fillers like alumina (Al2O3) and titanium (TiO2) with 100 µm dielectric coating thickness are added to epoxy, and the resultant permittivity is calculated. The electric field distribution with AC as applied voltage is calculated at the surface of the cone type spacer and the distribution. Finite element method (FEM), one of the proven numerical methods, is used for computing the electric fields at various points under consideration and is plotted. The results are presented and analyzed for various filler concentrations.