一种差动型高增益DC-DC变换器分析与设计

针对传统DC-DC变换器电压增益低、开关管电压应力较高、输入电流和输出电压纹波较大等问题，提出一种由两个多电平升压变换器差动连接而成的DC-DC变换器。首先，详细分析了所提变换器的拓扑结构、工作状态以及电路参数设计。理论分析结果表明，在占空比为0.5时，该新型变换器输入电流和输出电压的纹波相互抵消，具有明显的纹波抑制功能。同时，当电容器以互补开关方式运行时，电容器纹波的减少降低了电容器的尺寸。此外，该新型变换器无需添加额外的开关管，驱动及控制电路设计简单。然后，对所提变换器与其他类似变换器在电压增益、元件器数量以及半导体器件的电压应力等方面进行了对比分析，进一步说明了所提变换器的优越性能。最后，通过仿真研究和样机实验验证了理论分析的正确性，以及所提拓扑结构在降低元器件电压应力、提高电压增益方面的有效性。

Analysis and design of a differential high gain DC-DC converter

There are some problems such as the low voltage gain, high voltage stress in switch tubes, input current and output voltage with large ripple. This paper proposes a DC-DC converter, which is formed by differential connection of two multi-level boost converters. First, a detailed analysis is conducted on the topology, working state, and circuit parameter design of the proposed converter. The theoretical analysis results show that when the duty cycle is 0.5, the ripple of the input current and output voltage cancel each other, and this new converter has obvious ripple suppression function. When the capacitor operates in a complementary switching mode, the reduction of capacitor ripple reduces the size of the capacitor. In addition, the new converter does not require the addition of additional switches, and the design of the driving and control circuits is simple. A comparative analysis is conducted of the proposed converter and other similar converters in terms of voltage gain, number of components, and voltage stress of semiconductor devices, further demonstrating the superior performance of the proposed converter. Finally, the correctness of the theoretical analysis and the proposed topology structure are verified through simulation and prototype experiments. The converter can reduce component voltage stress and improve voltage gain.