Reduction of Proximity Effect in Coil Using Magnetoplated Wire

The upgrading of the efficiency of transformers and increase in the quality factor of inductors are required. For this purpose, it is necessary to reduce copper loss. Reducing the winding AC resistance is one method of reducing copper loss. Therefore, we propose the use of magnetoplated wire (MPW) for coil windings. An MPW is a copper wire (Cu wire) whose circumference is plated with a magnetic thin film. The resistances due to the proximity effect of Cu wire and MPW coils at a frequency of f=1 MHz, which have a diameter of D=4.54 mm, a wire diameter of d=0.09 mm, and a number of turns of N=102, are 4.2 Omega and 2.1 Omega, respectively; thus, the proximity effect decreases by half