Title :
Current driven synchronous rectifier with saturable current transformer and dynamice gate voltage control for LLC resonant converter
Author :
Ho, Godwin Kwun Yuan ; Yu, Ruiyang ; Pong, Bryan Man Hay
Author_Institution :
Electr. & Electron. Eng. Dept., Univ. of Hong Kong, Hong Kong, China
Abstract :
This paper proposes an improved current driven synchronous rectifier with saturable current transformer and dynamic gate voltage control feature for LLC resonant converter efficiency improvement. A model of saturable current transformer is proposed. Compared with other voltage driven and current-driven synchronous rectifier, this current driven synchronous rectifier has several outstanding characteristics. This synchronous rectifier is completely self-contained. It needs no external signal or power supply. It is also insensitive to parasitic inductance. Inherent dynamic gate voltage control reduces gate loss in the MOSFET by saturable current transformer. A 300W 400V-12V converter is built to demonstrate the advantages of the proposed current driven synchronous rectifier. High efficiency at 98% can be achieved. There is more than 4% efficiency improvement compared with schottky diode.
Keywords :
MOSFET; current transformers; rectifiers; resonant power convertors; voltage control; LLC resonant converter efficiency improvement; MOSFET; current driven synchronous rectifier; dynamic gate voltage control; efficiency 98 percent; gate loss reduction; power 300 W; saturable current transformer; voltage 400 V to 12 V; voltage driven synchronous rectifier; Capacitors; Current transformers; Logic gates; MOSFET circuits; Rectifiers; Voltage control; Windings;
Conference_Titel :
Applied Power Electronics Conference and Exposition (APEC), 2012 Twenty-Seventh Annual IEEE
Conference_Location :
Orlando, FL
Print_ISBN :
978-1-4577-1215-9
Electronic_ISBN :
978-1-4577-1214-2
DOI :
10.1109/APEC.2012.6166150
