Abstract：Regarding a discharge fault in the 500 kV gas-insulated transmission line (GIL) conduit gallery of a certain ultra-high voltage substation, an SF6 component test is conducted on the GIL corridor gas chambers to identify the faulty chamber firstly. Then, by inspecting the interior of the GIL corridor and performing a disassembly analysis of the triple-column insulators, the discharge process is ascertained. Subsequently, foreign matter in the gas chamber is collected and its components are analyzed, thereby determining the composition of the foreign matter and its possible source location. Finally, by hypothesizing and verifying possible locations of the foreign matter that could have caused the discharge, the exact source of the foreign matter is pinpointed, thereby proposing corresponding corrective and preventive measures, which is beneficial for improving the operational reliability of similar GIL corridors.
2026, Vol. 27 
