Reduction in Eddy Current Loss in Conductor Using Magnetoplated Wire

Coil resistance is broken down into DC resistance, resistance due to the skin effect and resistance due to the proximity effect. Most of the coil resistance is composed of resistance due to the proximity effect in the high-frequency range. Thus, the resistance due to the proximity effect, which is equal to the eddy current loss, must be reduced. The eddy current loss in a magnetoplated wire is smaller than that in a copper wire. The magnetoplated wire is a copper wire whose circumference is plated with a magnetic thin film. The eddy current losses in magnetoplated wire can be analyzed using the finite element method. However, the analysis time is long and there is a memory capacity restriction when using the finite element method. In this study, we derive the expressions of the skin effect and eddy current loss in a magnetoplated wire for ease of calculation. The result shows that eddy current loss in the magnetoplated wire is reduced to a factor of 0.25 or less in comparison with that in copper wire, and that the resistance of the magnetoplated wire can be reduced due to the proximity effect.