Highly efficient power inductors for high-frequency wide-bandgap power converters

Highly efficient power inductors for high switching frequencies are required to take full advantage of modern wide-bandgap (WBG) semiconductors in terms of power density and efficiency. However, appropriate inductors are usually not available from stock. In this paper a new design approach for high-frequency power inductors is presented using planar cores, 3D printed spiral bobbins and copper foil in vertical orientation. Even though the presented approach is based on low-cost copper foil instead of expensive litz wire, it does not suffer the typical drawbacks at high-frequency operation. It reduces the required amount of copper significantly and shows excellent copper utilization. The new design approach is presented in detail, key design parameters are discussed and simulation as well as measurement results are shown and analyzed.