Operation Mode Analysis and Peak Gain Approximation of the LLC Resonant Converter

    Authors

    X. Fang; H. B. Hu; Z. J. Shen;I. Batarseh

    Comments

    Authors: contact us about adding a copy of your work at STARS@ucf.edu

    Abbreviated Journal Title

    IEEE Trans. Power Electron.

    Keywords

    DC-DC power conversion; generalized analysis; resonant converter; STEADY-STATE ANALYSIS; FREQUENCY; Engineering, Electrical & Electronic

    Abstract

    With the advantage of achieving zero voltage switching for a wide input voltage range, the LLC resonant topology has become increasingly popular for use in high power density and high-efficiency power converter applications. However, when the LLC converter is applied to wide input voltage range applications, the widely used fundamental harmonic approximation is incapable of guiding the design due to its inaccuracy. Thus an accurate LLC converter model is desired. In this paper, a generalized mode analysis is presented that provides highly accurate prediction on resonant current and voltage behavior and dc gain characteristic. Also, because operation modes are affected by load, frequency, and gain conditions, the boundaries and distribution of modes are discussed and illustrated. Based on the mode analysis, an approximation method is developed to estimate the peak gain point, which is useful in LLC design. This approximation demonstrates high accuracy within the simulation results. An experimental prototype is built to verify the analysis.

    Journal Title

    Ieee Transactions on Power Electronics

    Volume

    27

    Issue/Number

    4

    Publication Date

    1-1-2013

    Document Type

    Article

    Language

    English

    First Page

    1985

    Last Page

    1995

    WOS Identifier

    WOS:000300581500031

    ISSN

    0885-8993

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