Effect of Lorentz force on the conducting contaminant trajectory in a three phase Gas Insulated Busduct

The main cause for the most of the failures in Gas Insulated Busduct is attributed to the presence of metallic particle contaminations in the form of loose particles, which may exist on the inner surface of outer enclosure of GIB or on HV conductor. These conducting particles under the influence of high voltage may acquire sufficient charge and randomly move in the inter electrode gap due to variable electric field. In this paper, conducting particle trajectory is obtained for 300 kV, 400 kV and 500 kV power frequency voltages in a Gas Insulated Busduct (GIB) with SF₆ as dielectric medium considering the effect of Lorentz force. Conducting contaminants considered are Copper, Aluminum and Silver particles of radius 0.1 mm and length 10 mm of wire type in a GIB of an outer enclosure diameter 500 mm and inner conductor of diameter 64 mm is considered. The motion of the wire particle and these particles will be of irregular cross section and can move in any direction and therefore the movement of the particle may be simulated using Monte-Carlo Technique.