State of the art GIS technology and trends

Modern gas insulated switchgears (GIS) technology has undergone continuous development since its introduction in the 1960's, when the use of sulphur-hexafluoride (SF6) gas was first introduced as an insulating and arc extinguishing medium. With the use of SF6, the world's first high voltage gas insulated switchgear was introduced into the market in 1968. Whilst many may consider this technology as mature, there have been continuous development-driven changes in GIS design, manufacture, test and operation. Consistent research and innovative development led to the nowadays compact and overall optimized switchgear. Today, GIS technology consists typically of a modular design and is filled with a minimum of SF6. The standardized structure is made to match various customers' specifications and allows realizing almost all substation configurations accordingly. Furthermore, it offers low life cycle costs and can be used for indoor and outdoor applications. What trends have shaped the GIS of today, and which will determine how GIS will further evolve into the future in terms of design, manufacture, test, and operation throughout its life cycle? What are the customers' visions and what are the manufacturers' answers?