Numerical study of electrode vaporization rates in an Automotive HVDC Relay in hydrogen and open air in a short circuit situation

Abstract

The occurrence of electric arcs during the unintended separation of contacts often does significant damage to the contacts. In high voltage direct current (HVDC) relays, such unintended contact separation mostly occurs during short circuit situations, which lead to the supply of large magnitudes of electric currents to the relays. Due to the high temperature of the resulting electric arcs, the contacts of the relays are rapidly and significantly vaporized. The vaporization of the contacts of a Panasonic AEV14012 relay is investigated in hydrogen and open air. Two relay samples are tested under similar short circuit conditions. The experimental results are used to validate a numerical model established in COMSOL to model electric arcs. The temperature of the arcs is estimated from the results of the numerical model and are used to estimate the vaporization rates of the electrodes in hydrogen and open air.