The internal arc fault test on a single pole of a three-pole dead tank vacuum circuit-breaker revealed that clean air performs comparably to SF6 gas and CO2 in terms of insulation during an internal arc, despite a steeper pressure increase. A well-designed pressure relief device effectively limits this pressure rise, ensuring safety and preventing compartment fragmentation. A validated simulation model using Simcenter Amesim accurately predicts pressure buildup, while a 3D CFD simulation in ANSYS® Fluent explores the arc fault process with various insulating media. Results indicate that SF6 leads to the highest pressure buildup, followed by air and CO2.
