Design studies on low voltage contactors by using transient finite element analyses with circuit coupling

The behaviour of a low voltage contactor is analyzed with nonlinear transient finite element analyses. For a simulation as close as possible to normal operational conditions, a voltage driven model is concerned additionally to a current excited model. A strong circuit coupling takes into account for the eddy currents in the copper shading rings. Thereby, different arrangements of the shading rings are analyzed in detail. A comparison of the steady state current characteristics obtained from the numerical calculations and from measurements shows a very good agreement