Computation of coupled current-magnetic field for vacuum interrupter

A coupled model of current conduction and static magnetic field is proposed, according to three dimensional (3D) axial magnetic fields (AMF) of two and three segments coil-type contact for a 72.5 kV/31.5 kA vacuum interrupter (VI). And the distributions of current density and electric potential are obtained using finite element method (FEM). Moreover, the conductor resistance and the characteristics of AMF are also investigated. The results show that the conductor resistance, the arc voltage and AMF generated by two segments coil-type contact is relatively larger than that that of the three segments coil-type contact.