Higher Power Density Decoupled Magnetic Device with Core Integrated Orthogonal Windings for Power Converters

• Published in: IEEE transactions on power electronics 2024-12, p.1-14
• Main Authors: Fayyaz, Shamroze, Munir, Muhammad Umair, Atef, Mohamed, Kim, Kyoung-Tak, Jeon, Jong-Kwon, Ahmed, Ashraf, Park, Joung-Hu
• Format: Article
• Language: English
• Subjects: Coils; core integration; dc-dc converters; DC-DC power converters; high power density; Inductors; integrated inductor; interleaved converters; Magnetic cores; magnetic device; Magnetic devices; Magnetic flux; Magnetomechanical effects; orthogonal windings; Performance evaluation; Saturation magnetization; Windings
• ISSN: 0885-8993; 1941-0107
• DOI: 10.1109/TPEL.2024.3510719

This paper proposes a three-plate, leg-less magnetic structure for integrated magnetic device to enhance the power density of the power electronics converters. The main idea could be used to integrate any magnetic device, such as decoupled inductors, decoupled transformers or decoupled inductor with transformer, in the same core. In this paper, a case of two decoupled inductors integrated in the same core using two orthogonal windings is presented. The proposed magnetic device features two inductive coils, wound on a single magnetic core, arranged perpendicularly in three-dimensional space. This specific configuration ensures nearly zero magnetic coupling between the coils, effectively transforming the integrated magnetic device into two independent inductors with higher power density. The three-plate structure distributes the magnetic flux in a more uniform manner, mitigating magnetic concentration within the structure. The uniform distribution of magnetic flux enables the device to handle stronger H-fields before reaching saturation, thus increasing the power density of the device. The design holds promise for various DC-DC converter applications, potentially leading to cost and size reduction with higher power density. The paper provides a comprehensive analysis of the magnetic performance of the proposed magnetic device through detailed Finite Element Method (FEM) simulations. The magnetic performance of the proposed device is compared with that of the recently proposed two-plate, quadratic-legs structure. The adoption of the three-plate design led to a 25% reduction in the magnetic flux density, for the same load conditions, enabling the device to handle 60% higher current than the quadratic-legs structure. A prototype, tested using a 250W 2-phase interleaved boost converter and compared with discrete core inductors, revealed that the proposed device achieved a 50% reduction in the volume of the magnetic component of the system without compromising system efficiency, which remained consistent at 94% for both discrete core inductors and the proposed magnetic device.