Investigation of gas discharge phenomena in a SF6 circuit breaker

A randomly stepped leader propagation model is proposed to investigate the gas discharge phenomena in a SF₆ circuit breaker. The model is based on physical principles of gas discharges and accounts for the insulation parameters, i.e. gas, gas pressure, gap geometry and insulating media. 3D electric field calculations in the arcing chamber of a SF₆ circuit breaker are implemented at each leader step. The gas discharge processes between the contacts and shield ring are numerically simulated and the leader propagation in the different insulating media is analyzed