The primary part of a gas-insulated switchgear consists of a stainless steel vessel filled with SF6 gas. The gas serves as an insulator in order to achieve the narrowest and most compact design.
The picture below shows an example of a vessel with the three busbars (phase L1, L2, L3) and arc-fault additives. Currently, the arc-fault additive consists of a metal and a protection sheet.
Picture 1: Gas-filled vessel with busbar system and protection against arc-fault (Example of one application)
In the event of a failure, the sheet metal serves to guide the electrical arc (5000 – 10000 °C) in a targeted manner. Due to the limited space in the container, the sheet metal is located close to the vessel wall.
To prevent the arc from burning out of the container in the event of a failure, a new material (as an economical alternative for the current solution) is required for protection.
The installation situation is shown in pictures 1 and 2.
Picture 2: Example for the need for protection against burning through of an electrical arc
10 tons insulating material per year are needed for the current solution.