Gas insulated transmission lines - GIL

GIL bus has evolved differently than bus used in gas insulated substations. GIS stations are a compact arrangement of circuit breakers, disconnects, earthing switches, voltage and current transformers etc. Usually connections between these active elements are only a few meters in length. Since the required electrical shapes for enclosures are often complicated, castings are used extensively for both active components and for the flanges used on interconnecting bus. A typical GIS bus section and elbow is shown in this paper.