Solid by-products of a CF3I-CO2 insulating gas mixtures on electrodes after lightning impulse breakdown

摘要

This paper investigates the solid by-products of CF3I–CO2 gas mixtures and their proposed use as anudalternative insulation medium in gas insulated switchgear and lines. The deposited by-products of aud30%–70% CF3I–CO2 gas mixture are experimentally investigated using stainless steel, aluminium andudcopper contacts whilst a standard 50 kV lightning impulse is used to cause electrical breakdown in theudgas mixture. Following breakdown, the accumulated by-products over the electrodes surface wereudexamined using an imaging microscope and scanning electron microscope. This paper discusses theudresults of microscope analysis on the surface of the electrodes and explores the effects that the detectedudby-products could have on high voltage CF3I–CO2 gas insulated equipment.