Determination of particle trajectory in gas insulated bus duct by Monte-Carlo technique

A method based on particle motion is proposed to determine the particle trajectory in Gas Insulated Substation (GIS) or Gas Insulated Busduct (GIB). In order to determine the movement of a particle in a GIB, an inner electrode diameter of 55 mm and outer enclosure diameter of 152 mm was considered. Aluminium and copper wires of 0.5 mm/10 mm were considered to be present on the enclosure surface. The motion of the wire (particle) was simulated using the charge acquired by the particles, the macroscopic field at the particle site, the drag coefficient, Reynold's number and coefficient of restitution. The distance travelled by the particle, calculated using the appropriate equations, is found to be in good agreement with the published work for a given set of parameters. The results are also presented for other set of parameters. In order to determine the random behaviour of moving particles, the calculation of movement in axial and radial directions was done at every time step using rectangular random numbers. Typically for Aluminium wire for a bus duct voltage of 100 kV RMS, the movement of the particle (0.5 mm/10 mm) for 2 sec was computed to be 26.02 mm in axial and 1002.3 mm in radial directions. Similar calculation is extended for a typical 220 kV (RMS) Gas Insulated Busduct.