Design und Optimierung einer keramischen Schaltstrecke hinsichtlich der Vermeidung von Zündbedingungen elektrischer Schaltlichtbögen in Gleichstromanwendungen

Abstract

This thesis investigates a novel direct current switch design in a multiphysics simulation environment, regarding the ignition of electric arcs. For testing purposes an electric ciruit including the switch, a load resistance and an inductance is configured. The switch concept works as a contact moving over a material with an inherent resistivity gradient to introduce an increasing resistance into the electric circuit. The resistance is increased, until the circuit current is reduced to low levels, approximating a shut off. The currents, voltages and electric fields in and around the switch geometry are analysed to prove the concept can reduce the current without igniting a volatile electric discharge. The electric breakdown behaviour is tested for various conductivity function inputs as switch material parameters and switch durations of approximately 50 to 1.5 ms. The parameter-variation finds several configuration avoiding electric arc ignition using the applied direct current switch concept.