A Magnetic‐Shunt‐Based Magnetic Structure for Coupled Inductor Filters

This article presents a magnetic structure for coupled inductor filters that simplifies the adjustment of the coupling factor between the windings and the target mutual and self‐inductances to achieve a zero‐ripple input current. The proposed structure utilizes a low‐permeability ferrite polymer in the core gap. This design significantly reduces the fringing flux and restricts the leakage flux path, allowing for precise tuning of the magnetic flux path and simplifying the circuit design. The proposal also decreases the required number of turns in each of the coupled windings, increasing the overall power density. The necessary equations to design the proposed structure are determined and validated through FEA simulation and experimental testing on a step‐up converter incorporating the designed coupled inductor. The results demonstrate the effectiveness of the proposed structure in achieving significant reductions in inductance requirements, enabling an increased power density while maintaining zero‐ripple operation under varied conditions.