Influence of Magnetic Field Induced by Nearby Phase on the AMF and TMF Characteristics Between Contacts in Vacuum

With the decrease of the size of the VCB, the influence of magnetic field induced by nearby phase (NP) becomes more significant. The objective of this paper is to determine the influence of magnetic field induced by NP on the AMF and TMF characteristics between contacts in vacuum under high current. The AMF contacts simulation model under influence of magnetic field induced by NP is established. The TMF contacts simulation model under influence of magnetic field induced by NP is established. The calculation results indicate that, for the AMF contact, the magnetic field induced by NP will shift the AMF distribution between contacts. The maximum deviation distance of the AMF peak value increases by 45.6%. The NP affects the strength of the AMF, with the maximum fluctuation of 1.8%. For the TMF contact, there is no significant difference in magnetic field distribution between contacts. The peak value of the force on the arc column fluctuates, with the maximum fluctuation of 3.3%. Moreover, the NP made the arc column more conducive to moving toward the edge of the contact, which may change at different arc column positions and current phases.