What is the difference in the proportion of core loss in common mode inductors at different frequencies?

Magnetic core loss (iron loss) comprises hysteresis loss and eddy current loss, with its proportion varying significantly with frequency:

 Low frequency band (<10kHz): Hysteresis loss dominates (directly proportional to the area of the hysteresis loop and frequency)

 Mid-frequency range (10kHz~1MHz): Eddy current loss increases with the square of frequency, gradually becoming the dominant component (especially in high-conductivity ferrites)

 High-frequency band (>1MHz):

 Ferrite core: Eddy current loss is dominant, requiring low-loss materials (such as optimized NiZn ferrite formulations) to suppress temperature rise

 Nanocrystalline/amorphous alloys: Due to their high magnetic permeability and low resistivity, eddy current losses increase faster, but the total losses may still be lower than those of ferrite under specific designs;

 Iron powder core: The granular insulation structure suppresses eddy currents, resulting in a slower increase in loss, making it suitable for high-frequency and high-current scenarios.