On electrostatic trapping of particle contamination in GITL systems

The insulation performance of gas-insulated transmission line (GITL) systems can be substantially affected by the presence and movement of contaminating metallic particles. The dynamics of wire and spherical particles in a coaxial-electrode system under AC voltage have been studied under different conditions. At voltages just above the lifting voltage the particle moved near the outer enclosure. Under appropriate conditions the particle can move into the high field region and eventually cross the interelectrode gap, thus causing a potential insulation hazard. Contaminating particles in a GITL system move randomly in the electric field. Control of contaminating particles is crucial for reliable operation of GITL systems. A numerical model of the contaminating particle´s motion in the interelectrode gap in a GITL system was used to study particle control methods in gas-insulated power apparatus