Title :
Three-level LLC series resonant DC/DC converter
Author :
Gu, Yilei ; Lu, Zhengyu ; Hang, Lijun ; Qian, Zhaoming ; Huang, Guisong
Author_Institution :
Coll. of Electr. Eng., Zhejiang Univ., Hangzhou, China
fDate :
7/1/2005 12:00:00 AM
Abstract :
Paper presents a three-level soft switching LLC series resonant dc/dc converter. Zero-voltage switching (ZVS) is achieved for each main switch without any auxiliary circuit. Voltage stress of each main switch is half of input voltage. Zero-current-switching (ZCS) is achieved for rectifier diodes. Wide input/output range can be achieved under low frequency range because of two-stage resonance. Only one magnetic component is required in this converter. Efficiency is higher in high line input, so this converter is a preferable candidate for power products with the requirement of hold up time. For design convenience, relationship between dc gain and switching frequency, load resistance is deduced. Its open load characteristic and short load characteristic are exposed to provide theory basis for no load operation and over current protection. Design consideration of four dead times is presented to assure that voltage stress for main switches is within half of input voltage and ZVS for each main switch is achieved. Finally the principle of operation and the characteristics of the presented converter are verified on a 500V-700V input 54V/10A output experimental prototype, whose efficiency reaches 94.7% under rating condition.
Keywords :
DC-DC power convertors; overcurrent protection; rectifiers; resonant power convertors; switching convertors; zero current switching; zero voltage switching; 10 A; 500 to 700 V; 54 V; overcurrent protection; rectifier diodes; switching frequency; three-level LLC series resonant DC-DC converter; voltage stress; zero voltage switching; DC-DC power converters; Diodes; Frequency; Magnetic resonance; Rectifiers; Stress; Switches; Switching circuits; Zero current switching; Zero voltage switching; Hold-up time; resonant converter; three-level;
Journal_Title :
Power Electronics, IEEE Transactions on
DOI :
10.1109/TPEL.2005.850921