基于LLC拓扑的宽电压输出车载电源研究

针对电动汽车车载DC-DC变换器的设计问题,对车载DC-DC变换器的宽范围应用需求进行了分析,总结了使用LLC拓扑设计宽范围DC-DC变换器的面临的问题,传统的基波分析法设计理论在宽范围DC-DC变换器中引起的误差很大,通过空载的LLC增益分析对其进行了验证。提出了一种结合基波分析法的限制条件与仿真的新设计方法,使得增益分析的误差大大减小,且对效率优化十分有效。最后搭建了一台2 k W的实验样机对理论分析进行了验证,并根据所提出的设计方法给出了电路关键参数的设计流程。研究结果表明:所设计的样机在10%~100%负载下均能实现软开关,且最高效率达到97.1%。

Wide output voltage range EV charger based on LLC resonant topology

Aiming at the design problem of DC-DC converter in electric vehicle, the wide range of application requirement of vehicle DC-DC converters was analyzed,and the problems of wide range DC-DC converter using LLC topology were summarized. The error caused by the tra-ditional fundamental wave analysis method in a wide range of DC-DC converters was very large, it was verified by no-load LLC gain analysis. A new design method combined with the limitation of fundamental wave analysis and simulation was proposed, which greatly reduced the error of gain analysis and was very effective for efficiency optimization. Finally, a 2kW experimental prototype was built to validate the theoretical analysis. Based on the design method proposed in this paper, the design steps of the key parameters of the circuit were given. The results in-dicate that the prototype can achieve soft -switching under 10％ -100％ load, and the maximum efficiency is 97. 1％.