Calibration of UHF sensors for GIS: Comparison of different methods and testing of a calibration system based on a conical antenna

Different methods of calibrating UHF sensors for gas insulated substations (GIS) were investigated in the past. This paper compares existing calibration methods and shows their advantages and disadvantages. To overcome the known disadvantages, the design of a novel cone calibration system is described. The paper delivers insight into the development, design and testing of this new calibration system. The measurement results show that the presented method gives accurate calibration results with a very low overall uncertainty. Due to its surprisingly simple structure, its low price and the low overall measurement uncertainty, it is the preferred method for calibrating UHF sensors for GIS applications.