大功率UPS系统中宽增益DC/DC变换器的研究

Research on a High Voltage Gain DC/DC Converter Applied in High Power UPS System

为减少蓄电池的串联数量、延长蓄电池组单独供电的工作时长,设计一种应用在大功率不间断电源系统(Uninterruptible Power Supply,UPS)中的宽增益DC/DC变换器,接口于UPS系统中直流母线与蓄电池组之间,在功能上提升蓄电池组供电可靠性的同时也降低蓄电池组的体积和成本。相比传统DC/DC变换器,所提拓扑在结构上进行优化,将所用功率器件的电压应力进行大幅度降低,同时极大地提高了电压增益上限和实际工况下的增益允许变化范围。通过试验验证,所提出变换器可以在PI电压闭环的控制策略下实现4~10倍的升压增益,使用的所有功率开关器件的电压应力仅为输出电压的三分之一。并通过效率试验验证了该变换器适用于大功率应用场景,具有较高的研究和推广价值。

In order to reduce the number of batteries in series and extend the working time of battery separate power supply,a high voltage gain DC/DC converter applied in uninterruptible power supply(UPS)system was designed,which was connected between DC bus and batteries in UPS system.It can not only improve the reliability of battery power supply in function,but also reduce the volume and cost of battery.Compared with the traditional DC/DC converter,the proposed topology was optimized in structure,which greatly reduces the voltage stress of the power devices used,and greatly improves the upper limit of voltage gain and the allowable gain variation range under actual conditions.Experimental results show that the proposed converter can achieve 4~10 times boost gain under PI voltage closed⁃loop control,and the voltage stress of all power switching devices is only 1/3 of the output voltage.The efficiency experiment shows that the converter is suitable for high⁃power applications,which has high research and engineering promotion value.