On July 6, 2020, XJTU and the Pinggao Group joint research team accounced successful development of China’s first 126kV fluoride-free Gas Insulated Switchgear (GIS).
The joint research team applied China's independently developed 126kV single-break vacuum arc-extinguishing chamber as the breaking unit; used carbon dioxide as the single-break medium of GIS integral insulating, disconnecting, and earthing switches, thus designing an environmentally-friendly GIS. The team also found ways to deal with the breaking reactive low current of disconnecting/earthing switches based on modeling, simulation, analysis, and experimentation. The GWP value of carbon dioxide used in the GIS model is smaller than one ten-thousandth of GWP of sulfur hexafluoride gas. A 99.99% reduction in carbon dioxide equivalence per each GIS allows the machine to work in -40℃ temperatures and extremely cold regions due to the low liquefaction temperature. Products are made with lightweightaluminum alloy shells, have good anti-corrosive properties, and are inexpensive.