Measurement system for very fast transient overvoltages in gas insulated switchgear

During switching operations of disconnectors in a gas insulated switchgear (GIS) several pre- or restrikes occur between the switching contacts. Thereby steep voltage rises get initiated and propagate inside the GIS. For the measurement of these very fast transient overvoltages (VFTO) a capacitive high voltage measurement system with an analog bandwidth of over 100 MHz was developed. The characteristics and the development process of the sensors are presented in this paper.