Time Domain Analysis of Eddy Currents in Saturating Magnetic Materials

S. Thompson
Applied Research Laboratory
Penn State University
State College, PA
Published in 2011

Eddy current phenomena in conducting magnetic media are well understood, although the detailed behavior at high drive levels leading to magnetic saturation are not always well explained. This paper considers the example of an infinite cylindrical magnetic core with an external coil.

At high frequencies the interaction of the induced flux and current in the core confine them both to a thin layer inside the cylindrical surface of the core. As this skin layer saturates, additional flux causes the layer to thicken and eventually to fill the entire area of the core. The detailed nature of magnetic saturation with eddy currents will be discussed using time domain analysis with nonlinear magnetic material properties.