Application of novel sensor technology in an environmental friendly SF6 free medium voltage gas insulated switchgear pilot setup

Abstract:
Current gas insulated switchgear (GIS) technologies use SF6 or other mixtures of synthetic gases as insulation medium and often also as breaking medium. Despite its beneficial insulation properties, SF6 is the most hazardous greenhouse gas humanity knows. Recent studies prove that reported amounts of SF6 emissions can only explain 20% of actual emissions. Increased environmental and regulatory concerns as well as the costs of gas handling and maintenance are commonly cited as disadvantages to SF6 based switchgear. An effort is made in a pilot setup to test a new technology of gas insulated electrical switchgear using dry compressed air as insulation medium for medium voltage (MV) applications up to 36kV. A novel sensor technology is assessed to be applied in the switchgear gas insulated compartment to continuously monitor and measure vital parameters such as moisture, gas tightness, ageing, partial discharge and temperature level during operation. This would enable a better-informed decision tree for remote diagnosis and control operations. The placement of passive antennas and passive wireless sensors in the dry air compartment to optimize signal reception is also discussed. Potential applications for predictive maintenance, and eventually smart grid application are discussed.