Numerical investigations on the electric arc behavior upon contact opening in a low-voltage switch under the effect of external magnetic field

Abstract

This paper is devoted to investigate the effect of a strong external magnetic field on the electric arc created by contact opening in a low-voltage switch. The low-voltage switch is powered by a DC generator with an RL charge as in photovoltaic installations. During contact opening, the arc motion is dominated by Laplace and hydrodynamic forces. An external magnetic field is added to strengthen the magnetic forces and to accelerate the arc extinction. Significant differences depending on the external magnetic field intensity can be investigated. Numerical simulations, developed using COMSOL Multiphysics, are compared to experimental measurements performed on experimental device specially designed for tests to provide a better understanding of the physical phenomena involved.