An Open Load Solution for the LLC Resonant Converter
LLC resonant converter is widely used in PDP TV and LCD TV power supply recently years for its ZVS operation of primary switches and ZCS operation of secondary rectifiers. However the unstable output voltage and very high switching frequency when LLC converter operated at open load or light load condition are always a headache for the circuit Designers. One solution to this issue is the dummy load employed but with the penalty of additional power loss, cost and lower efficiency. This paper analysis the root causes of the open load issue of LLC converter in detail and proposed a simple and practical solution to solving this issue. Using the proposed solution, the LLC converter can operates stable with no dummy load and more narrow frequency range. Finally, a 130KHz, 80V/3.6A PDP TV power supply employed this solution achieves at least 0.6％ efficiency improvement and maximum switching frequency reduced from 288KHz to 141KHz.
Guodong Yin Chao Yan Qinyou,zhang Zhiying Chen Jianhong Zeng Jianping Ying
Delta Power Electronics Center 238 Minxia Road, Caolu Industry Zone, Pudong, Shanghai, 201209, China
国际会议
PCIM China 2007(International Conference Power Electronics)(2007年中国电力电子技术国际会议)
上海
英文
2007-03-21（万方平台首次上网日期，不代表论文的发表时间）