Induction Currents from Circular Coils

Application ID: 124


A time-varying current induces a time-varying magnetic field. The magnetic field induces currents in neighboring conductors. The induced currents are called eddy currents. In this model, the phenomenon is illustrated by a time-harmonic field simulation as well as a transient analysis, where the eddy currents resulting from the source being switched on are studied.

Two current-carrying coils are placed above a copper plate. They are surrounded by air, and there is a small air gap between the coils and the metal plate. The external source is applied as a current density, but the total current density in the coils is obtained only by taking the induced currents into account. The time-harmonic case will show the skin effect, that is, that the current density is high close to the surface and decreases rapidly inside the conductor.

This model example illustrates applications of this type that would nominally be built using the following products: