Research on the dynamic behavior of the arc between contacts of DC contactor

Based on magneto-hydrodynamics (MHD) theory, an air arc model is set up for the contacts and arc inducing plate at chamber inlet of a certain type of DC contactor and the dynamic behavior of the arc is simulated. The variation laws of arc length and the main conductive area migrating from moving contact to arc inducing plate were studied quantitatively under the influence of breaking speed and the applied magnetic field. The relationships between the change of breaking condition and position of conductive area, the migration time of area with high conductivity are revealed. And the experimental platform is set up to study arc dynamic development process of DC contactor which is consistent with the simulation results under the same conditions. The research of this paper has certain guiding significance for improving the breaking capacity of DC contactor and optimizing the structure of arc extinguishing chamber.