一种可变结构型高效宽增益多谐振软开关直流变换器

A Variable Topology Multi-Resonant Soft-Switching DC-DC Converter with High Efficiency and Wide Gain

该文提出一种可变结构的多谐振软开关直流变换器。此变换器采用双变压器结构,运用两个互补导通的辅助开关管进行变换器拓扑结构的转换。相互变换的工作模态有三种,能够满足不同工况对高电压增益或高变换效率的要求。此外,该文通过合理设置谐振频率和增益点的方式对变换器的谐振参数进行设计。随后,针对额定条件下变换器同时传递基波和3次谐波能量的工况,构建同时考虑基波和3次谐波的损耗模型,对变换器的损耗分布进行详细估算。最后,为验证理论分析的可靠性,基于一台实验样机对所述变换器进行功率实验验证,在输入电压80~600V变化范围内,输出电压始终稳定在400V,在获得较宽电压增益范围的同时实现了全增益范围内的高效率变换,变换器最高效率达97.6%。

A variable topology multi-resonant soft-switching DC-DC converter is proposed in this paper.Applying the double transformer structure,this converter can transform the topological structure through two complementary turn-on auxiliary switches.There are three working modes,which can meet the requirements of high voltage gain or high efficiency under different working conditions.In addition,resonant parameters of the converter are designed by setting the resonant frequency and gain point reasonably.Subsequently,according to the condition that the converter transmits the fundamental and third harmonic energy simultaneously under rated conditions,a loss model considering both the fundamental wave and the third harmonic is constructed,and the loss distribution of the converter is estimated in detail.Finally,in order to verify the reliability of the theoretical analysis,this paper conducted a power experiment on the converter based on an experimental prototype.Within the input voltage range of 80~600V,the output voltage is always stable at 400V,and a wide voltage gain range is obtained.At the same time,high efficiency conversion within the full gain range is achieved,and the maximum efficiency of the converter is 97.6%.