New geometry integrated inductors in two-channel interleaved bidirectional converter

A new geometry of integrated inductors for two-channel interleaved bidirectional converter is presented in this paper. The new geometry module integrates two individual inductors by stacking three I-cores. The middle I-core provides a shared flux path with low reluctance which uncouples the two inductors. The air gaps are constructed by separating the I-cores using copper foil windings with well-defined thickness. In this work, inverse connection and direct connection for the two integrated inductors have been analyzed. For the inverse connection, a unique saturation behavior in the middle I-core has been shown. The integrated inductors with new geometry make it possible to build low-profile, low-cost, flexibility DC/DC converters, and it can be extensively designed for low-voltage and high-current required by modern digital applications. Experiment results obtained from a 48V-12V 30A two-phase interleaved buck converter, demonstrates the difference in the inverse connection and the direct connection. Both efficiencies are above 91% from half to full output current.

[1]  A. Podoltsev,et al.  Analysis of effective resistance and eddy-current losses in multiturn winding of high-frequency magnetic components , 2003 .

[2]  Peng Xu,et al.  Design of 48 V Voltage regulator modules with a novel integrated magnetics , 2002 .

[3]  Michael A. E. Andersen,et al.  Optimal design and tradeoffs analysis for planar transformer in high power DC-DC converters , 2010, The 2010 International Power Electronics Conference - ECCE ASIA -.

[4]  Wei Chen,et al.  Winding loss mechanism analysis and design for new structure high-frequency gapped inductor , 2005, IEEE Transactions on Magnetics.

[5]  Xingkui Mao,et al.  Winding loss mechanism analysis and the design for a new structure high-frequency gapped inductor , 2005 .

[6]  M. Duffy,et al.  Distributed (parallel) inductor design for VRM applications , 2005, IEEE Transactions on Magnetics.

[7]  David V. Thiel,et al.  Charactoristics of High Frequency Planar Transformer with Helical Winding Structure , 2000 .

[8]  Yim-Shu Lee,et al.  Interleaved three-phase forward converter using integrated transformer , 2005, IEEE Transactions on Industrial Electronics.

[9]  J.D. van Wyk,et al.  Comparison of Different Designs of a 42-V/14-V DC/DC Converter Regarding Losses and Thermal Aspects , 2007, IEEE Transactions on Industry Applications.

[10]  Peng Xu,et al.  Investigating coupling inductors in the interleaving QSW VRM , 2000, APEC 2000. Fifteenth Annual IEEE Applied Power Electronics Conference and Exposition (Cat. No.00CH37058).

[11]  Po-Wa Lee,et al.  Steady-state analysis of an interleaved boost converter with coupled inductors , 2000, IEEE Trans. Ind. Electron..

[12]  Søren Petersen,et al.  Improved geometry of integrated magnetics for the hybridge topology , 2002 .

[13]  Peng Xu,et al.  Integrated planar inductor scheme for multi-module interleaved quasi-square-wave (QSW) DC/DC converter , 1999, 30th Annual IEEE Power Electronics Specialists Conference. Record. (Cat. No.99CH36321).

[14]  H. Kosai,et al.  Coupled Inductor Characterization for a High Performance Interleaved Boost Converter , 2009, IEEE Transactions on Magnetics.

[15]  Arthur F. Witulski,et al.  Introduction to modeling of transformers and coupled inductors , 1995 .