VacDouble

Properties of switching vacuum arcs in high-voltage applications

Circuit breakers for high currents at high voltages in power distribution networks traditionally contain the greenhouse gas sulphur hexafluoride SF6. One alternative are vacuum switches, which have so far only been used in the medium-voltage range. In order to implement high-voltage circuit breakers with vacuum arcs, large contact gaps and series connections of contacts must be realized. In this project, the applicants want to investigate the special behaviour of long vacuum arcs depending on the polarity of the moving electrode. The aim is to elucidate the physical mechanisms involved in the formation of anode spots in long arcs and compare them with the known behaviour in short arcs. INP will use imaging optical emission spectroscopy in the form of fast video spectroscopy accompanied by suitable model approaches for species densities and radiation transport. Insides into the mechanisms of the anode spot establishment and the reasons for the asymmetric behaviour in dependence on the polarity of the moved electrode are expected.

This is a joint project with the partner Technical University Braunschweig, elenia Institut für Hochspannungstechnik und Energiesysteme funded by the German Science Foundation and running from 2026 to 2029.

Funding number: 576950665