Overview of Planar Magnetics for High-frequency Resonant Converters

With the continuous development of power supplies toward miniaturization, light weights, and high levels of integration, research on high-frequency resonant conversion based on planar magnetics is becoming extensive. Combining the soft-switching characteristics of resonant converters with those of wide bandgap devices, the switching frequency can be increase to the MHz range, and the power density of the entire system can be improved considerably. However, higher switching frequencies impose new requirements for the structural design, loss distribution, and common mode (CM) noise suppression of passive magnetic components. Herein, a thorough survey of the-state-of-the-art of planar magnetics in high-frequency resonant converters is conducted. Printed circuit board winding-based planar magnetics, magnetic integration, and power-loss optimization strategies are summarized in detail. Suppression methods for CM noise in high-frequency planar magnetics are also clarified and discussed. An insight view into the future development of planar magnetics for high-frequency resonant converters is presented.