Abstract:

In response to the problem that traditional low voltage DC circuit breakers weaken their arc extinguishing ability when the current is reversed due to the unidirectional magnetic field, the arc simulation model of non-polar low-voltage Dc circuit breaker based on COMSOL is established to analyze the arc motion of non-polar low-voltage Dc circuit breaker under the reverse current. The influence of magnetic field and current on the arc-extinguishing ability of non-polar low-voltage Dc circuit breaker is analyzed. The simulation results show that the non-polar low-voltage Dc circuit breaker can eliminate the blocking effect of current reversal on arc motion, and the arc extinguishing ability is strongest at 240 mT and 16 A. In addition, the simulation results are consistent with the experimental results. The arc-extinguishing ability of the non-polar low-voltage Dc circuit breaker is the strongest in the appropriate magnetic field, and the smaller the current is, the strongest arc extinguishing ability.

Key words: current reverses, arc extinguishing ability, two-dimensional arc simulation, non-polar low voltage DC circuit breaker, arc motion