By using a magnetically plated copper wire with a ferromagnetic thin film layer for the coil wire, high frequency loss can be reduced compared to conventional polyurethane copper wire. This is due to the proximity effect generated in the coil being reduced by the magnetic plating layer, and due to the effective resistance of the conductor being lowered.
In this example, high frequency resistance values are obtained from choke coil copper loss analysis results using JMAG’s layer coating mesh function, and the effectiveness of reducing the resistance value of the coil using magnetically plated wire is confirmed.
Specification of Copper Wire
Comparisons of AC Resistance Value Frequency Characteristics
From fig. 2, it can be seen that when using magnetically plated wire, the AC resistance is lower than when polyurethane copper wire is used.
Comparison of Copper Loss Density Distributions
From fig. 3, it can be seen that joule loss when using magnetically plated wire is lower than when using polyurethane copper wire.
This shows that there is an influence from the proximity effect of coil wire being reduced when magnetically plated wire is used.
Comparison of Magnetic Flux Density Distributions
The figure shows that the magnetic flux density in the copper wire when using magnetically plated wire is smaller than when using polyurethane copper wire.
As shown in the figure, when magnetically plated wire is used, the number of isolines in the copper wire is large indicating that the magnetic flux concentrates on the copper wire surface, and the difference in the magnetic flux density between the copper wire interior and surface is higher than that for polyurethane copper wire.
Since a magnetic circuit is formed around the copper wire in the magnetic layer when a magnetically plated wire is used, and since the magnetic flux generated by the proximity effect in the wire interior is lower, it is seen that this is effective in reducing current bias.