一种输入低压大电流/输出高电压高频组合式直流变换器

针对飞机航空电源高可靠性和高功率密度的要求,提出并采用了一种输入低压大电流/输出高电压的组合式变换器.该组合式变换器以双管正激变换器为基本构成单元,输入端同时采用电路模块并联和功率开关管并联方式来提高输入导电电流能力,输出端采用电路串联的方式来提高输出电压能力.由于采用交错并联(interleaving)控制技术、以及利用功率MOSFET导通电阻的正温度系数特性,组合式变换器除具有双管正激变换器的内部桥臂抗直通能力强的优点外,还具有所有功率开关管自然均流、输入输出电压增益高、输出端二极管电压应力低、以及输入和输出滤波器体积小重量轻等特点.本文对该组合式变换器拓扑进行了详细的分析和仿真,并应用于某型号航空电源.

A High-Frequency Combined Converter With Low Voltage and High Current Input and High Voltage-Output

A novel high frequency combined converter topology with low voltage and high current of input-end and high voltage of output-end is presented to meet the demands of high reliability and high power density in the aeronautical power supply applications. By connecting in parallel two-transistor forward converter modules and power switches in the input-end, and by connecting in series the converter modules in output-end, the proposed converter has many advantages such as naturally sharing current of power switches, naturally sharing output-voltage, high voltage gain, no phenomenon of direct short circuit in the input DC link, low voltage stress of second-side diodes, small volume of input and output filters and so on. The analysis and simulation results show that the proposed converter is very suitable for the applications in low voltage and high current of input-end and high voltage of output-end, and it has been successfully applied to a certain aeronautical power supply.