Efficiency-Oriented Optimal Design of the LLC Resonant Converter Based on Peak Gain Placement

The LLC resonant converter topology is widely used in dc-dc converter applications due to its advantages in achieving high efficiency and high power density. However, due to the complexity in the analysis, the converter lacks a clear design guideline on the selection of resonant tank parameters. In this paper, an optimization method is developed based on the operation mode analysis and peak gain placement. Following this approach, the converter can minimize the conduction loss while maintaining the required gain range. A 400-W, 400-V output and 25-38 V input LLC converter is built using the proposed method, which achieves above 98% peak efficiency. As a comparison, the conventional searching method is used to reselect the LLC parameters for the same specifications, and the experimental results show that the optimal design has better performance.

[1]  A.J. Gilbert,et al.  Analysis of CLL Voltage-Output ResonantConverters Using Describing Functions , 2008, IEEE Transactions on Power Electronics.

[2]  Gun-Woo Moon,et al.  LLC Resonant Converter With Adaptive Link-Voltage Variation for a High-Power-Density Adapter , 2010, IEEE Transactions on Power Electronics.

[3]  F. Lee,et al.  LLC resonant converter for front end DC/DC conversion , 2002, APEC. Seventeenth Annual IEEE Applied Power Electronics Conference and Exposition (Cat. No.02CH37335).

[4]  Jianping Ying,et al.  A Novel Precise Design Method for LLC Series Resonant Converter , 2006, INTELEC 06 - Twenty-Eighth International Telecommunications Energy Conference.

[5]  Z. Qian,et al.  Three level LLC series resonant DC/DC converter , 2004 .

[6]  C. Oeder,et al.  A comparison of different design methods for the multiresonant LLC converter with capacitive output filter , 2010, 2010 IEEE 12th Workshop on Control and Modeling for Power Electronics (COMPEL).

[7]  G. Ivensky,et al.  Approximate Analysis of Resonant LLC DC-DC Converter , 2011, IEEE Transactions on Power Electronics.

[8]  Christian Oeder.  Analysis and design of a low-profile LLC converter , 2010, 2010 IEEE International Symposium on Industrial Electronics.

[9]  Bong-Hwan Kwon,et al.  High-performance front-end rectifier system for telecommunication power supplies , 2006 .

[10]  Jung-Hui Cheng,et al.  Analytic solutions for LLCC parallel resonant converter simplify use of twoand three-element converters , 1998 .

[11]  Robert L. Steigerwald.  A comparison of half-bridge resonant converter topologies , 1987 .

[12]  I. Batarseh,et al.  A generalized program for extracting the control characteristics of resonant converters via the state-plane diagram , 1995 .

[13]  Yan Liang,et al.  Optimal design methodology for LLC resonant converter , 2006, Twenty-First Annual IEEE Applied Power Electronics Conference and Exposition, 2006. APEC '06..

[14]  Ashoka K. S. Bhat.  A generalized steady-state analysis of resonant converters using two-port model and Fourier-series approach , 1998 .

[15]  Xiaogao Xie,et al.  Analysis and Optimization of LLC Resonant Converter With a Novel Over-Current Protection Circuit , 2005, IEEE Transactions on Power Electronics.

[16]  I. Batarseh,et al.  Steady state analysis and performance characteristics of the LLC-type parallel resonant converter , 1994, Proceedings of 1994 Power Electronics Specialist Conference - PESC'94.

[17]  Issa Batarseh.  State-plane approach for the analysis of half-bridge parallel resonant converters , 1995 .

[18]  Moon-Young Kim,et al.  Analysis of LLC Resonant Converter considering effects of parasitic components , 2009, INTELEC 2009 - 31st International Telecommunications Energy Conference.

[19]  R. Martinelli,et al.  Steady-state analysis of the LLC series resonant converter , 2001, APEC 2001. Sixteenth Annual IEEE Applied Power Electronics Conference and Exposition (Cat. No.01CH37181).

[20]  E. Janssen,et al.  Design of a 1-MHz LLC Resonant Converter Based on a DSP-Driven SOI Half-Bridge Power MOS Module , 2007 .

[21]  M.R. Zolghadri,et al.  Designing an Adjustable Wide Range Regulated Current Source , 2010, IEEE Transactions on Power Electronics.

[22]  T. Duerbaum.  First harmonic approximation including design constraints , 1998, INTELEC - Twentieth International Telecommunications Energy Conference (Cat. No.98CH36263).

[23]  I. Batarseh,et al.  Operation Mode Analysis and Peak Gain Approximation of the LLC Resonant Converter , 2012, IEEE Transactions on Power Electronics.