Application of a Novel Nanocrystalline Ribbon-Based Integrated Inductive-Capacitive Core in LLC Resonant Converters

LLC resonant converters are widely used in modern industrial applications, but passive components such as resonant inductors and capacitors typically occupy significant space, which limits further improvements in power density. In this paper, a novel inductive-capacitive magnetic core structure for LLC converters based on FeCuNbSiB nanocrystalline ribbon is proposed, which integrates both the resonant inductor and capacitor. This design enhances power density and eliminates the cost associated with the resonant capacitor. The Fe-based nanocrystalline ribbon core offers enhanced magnetic properties, such as reduced hysteresis loss and increased magnetic saturation, as well as improved mechanical strength when compared to traditional ferrite cores. A preliminary prototype has been constructed to verify the feasibility of the proposed structure. Experimental results indicate that when both the resonant inductor and capacitor are integrated into the core, the electric and magnetic fields do not interfere with each other. ©2025 IEEE.