Experimental Investigation of Vacuum Arc Under Quadrupolar Axial Magnetic Field Contact

Axial magnetic field (AMF) can effectively control vacuum arc by making it maintain diffuse state. In this paper, a quadrupolar contact which can generate a AMF is investigated by simulations and experiments. Experiments were carried out at circuit current from 12 to 28kA, and at least three experiments were performed for each current level. By using a high-speed digital video camera, the arc behavior was recorded, meanwhile, the arc voltage and arc current were also recorded. The magnetic field distribution and Ampere Force were calculated and analyzed. As a result, the evolution process of the arc can be interpreted. Simulation results show that a quadrupolar axial magnetic field distribution was generated by the special current flow. It was observed that arc column was distributed in four areas in the electrodes at low current and small gap distance. With the current and gap distance increased, anode became active and anode jets were generated.