Buck-Boost隔离直流转换器设计

在Buck-Boost隔离直流转换器宽范围输入电压的条件下，分析了典型的全桥Boost转换器拓扑结构，由于存在的谐振电感包括漏电感，全桥Boost转换器只能采用双边沿调制。该转换器采用UC3895作为控制器，对全桥单元采用移相转换控制的方式，为了提高全桥Boost转换器系统的可靠性和效率，采用三模式两频率控制方式，在输入宽范围电压的情况下，最高500V输入，360V输出。在此采用Matlab软件进行仿真，实验结果表明输入电压平均效率范围是96．2％，最高效率能达到97．5％。

Design of isolated Buck-Boost DC/DC converter

The topology structure of a typical FB Boost converter was analyzed under the condition of wide range input voltage of isolated Buck-Boost DC/DC converter. The FB Boost converter can only adopt two-edge-modulation （TEM） due to the resonant induction including the leakage induction. The converter takes UC3895 available in market as the controller to control the FB-cell with phase-shifted. In order to improve the reliability and efficiency of the FB-Boost converter, a three- mode dual-frequency control mode was used. The maximum input voltage is 500 V and the output is 360 V in the case of the wide range input voltage. The Matlab software was adopted for simulation. The result shows the the average efficiency range of the input-voltage is 96.2% and the highest efficiency can reach to 97.3%.