Abstract：Due to the advantages in conversion efficiency and power density,the traditional center-tapped capacitive secondary-side rectifier configuration is widely used in current mode DC-DC converters,such like LLC resonant converter,isolated push-pull boost converter,and etc. However,the oscillation occurring between the secondary-side leakage inductance of the power transformer and the parasitic junction capacitor of the rectifier during the transition interval increases the voltage stress across the rectifier a lot. It has to use the rectifier with higher breakdown voltage rating,which restricts the improvement of the whole conversion efficiency further. Additionally,the traditional center-tapped capacitive rectifier configuration suffers high current ripple which increases the conduction loss and the design complexity of the output filter. This paper analyzes the improved capacitive rectifier configuration in detail in order to effectively achieve voltage stress clamping across the rectifier and current ripple elimination by using flying balance capacitor for the output filter design and finally improve the whole conversion efficiency and reduce the design complexity of the output filter.
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2013, Vol. 28 
