Proposed Multi-Element Resonant Converters

The necessity of developing high frequency, high power density converters with very high efficiency for distributed power supply systems, leads to the wide applications of resonant converters. Resonant dc-dc converters are becoming more and more popular in the power electronics field. Resonant converters can achieve zero-voltage-switching or zero-current-switching and thus greatly reduce the switching losses.  High power density and high efficiency can be accomplished.  The conventional resonant converters can achieve soft switching but also generate large circulating energy.  The conduction losses are concerns for conventional resonant converters.  Meanwhile, for conventional resonant converters, it is difficult to achieve over load or short circuit protection at very high switching frequency.  The proposed multi-element resonant converters can overcome the drawbacks of the conventional resonant converters.  For instance, with higher order harmonics injection concept, one of the proposed 5-element, LCLCL converter can achieve much lower RMS current than conventional resonant converters.  Conduction loss can be reduced.  The proposed LCLCL resonant converters can achieve over load and short output circuit operation without damaging the circuit.  As a result, circuit startup and circuit short protection problems are overcome.  In addition, the proposed LCLCL resonant converters can still achieve ZVS operation at full load to zero load range.  High frequency, high power density and high efficiency can be accomplished.  In summary, the proposed 4-element, 5-element and high order element resonant converters can achieve very low switching loss and conduction loss.  Short circuit protection is another superior characteristic of the proposed multi-element resonant converters.  The performance of dc-dc converter can be improved significantly with the proposed multi-element resonant topologies.
Patent Information:
App Type Country Serial No. Patent No. File Date Issued Date Patent Status
US Utility *United States 12/136,413 7,742,318 6/10/2008 6/22/2010 Issued
For Information, Contact:
Li Chen
Licensing Associate
Virginia Tech Intellectual Properties, Inc.
(540) 443-9217
Dianbo Fu
Fred Lee
Ya Liu
Ming Xu
Power Conversion/Control