Contactless and non-invasive determination of the position of an axially blown switching arc in a circuit-breaker model

High voltage gas circuit breakers filled with the insulation gas sulphur hexafluoride are the main safety elements for the interruption of operating and fault currents in today's power grids. In the context of the recent debate on climate change the research on alternative insulation gases is forced. Preceding investigations using carbon dioxide as one of the most promising alternative gases show that a deeper understanding of the physical processes during the interaction of the insulation gas and the switching arc in an insulation nozzle system is necessary if these gases are considered as possible substitutes for sulphur hexafluoride. For this purpose a non-invasive measuring method has been developed which allows the determination of the spatial arc resistance distribution of an axially…