Free Conducting Particles in Compressed Gas Insulation

This paper presents an electrostatic study of free conducting particles that contaminate com pressed gas-insulated high voltage apparatus and transmission lines. Analytical and numerical techniques are used to describe the effect of the particle charge and the magnitude of the ambient electric field on the field intensification on and near the particle surface. The electrostatic force acting on filamentary and spherical particles as they lift off one electrode and move towards the other, is also analyzed. The techniques developed in this study enable the construction of a breakdown voltage profile which describes the instantaneous voltage required to break down the insulation as the particle moves between electrodes.