LLC Resonant Converter

  • Ivo BarbiEmail author
  • Fabiana Pöttker
Part of the Power Systems book series (POWSYS)


This chapter studies the LLC resonant converter operation in different modes. First harmonic approximation (FHA) is used to obtain the main converter characteristics in steady-state, including the dc voltage static gain. The obtained equations and curves are used to design circuit parameters and predict performance, which is verified through numerical simulation. Operation below and above the resonance frequency is discussed, along with the impact of the operation region on the commutation of the power switches. The chapter also includes numerical examples to illustrate the theoretical analysis, proposed exercises with solutions and numerical simulations.


Resonant Converter First Harmonic Approximation (FHA) Static Gain Resonant Capacitor Topological State 
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© Springer International Publishing AG, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Federal University of Santa CatarinaFlorianópolisBrazil
  2. 2.Department of ElectronicsFederal University of Technology—ParanáCuritibaBrazil

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