高频双Buck全桥逆变器的功率损耗分布分析

Analysis of Power Loss Distribution for High-frequency Dual-Buck Full-bridge Inverter

为了对高频条件下的变换器效率进行更加精准的估算,基于一台400 kHz高频双buck逆变器,提出了适用于高频变换器的损耗分布分析方法。该方法在分析开关过程的基础上,对开关管、二极管的开关损耗和导通损耗进行了详细估算,并根据电感磁滞回线,同时计及高频条件下的电容损耗对其磁性损耗进行了估算。此法充分考虑了高频工况对变换器损耗分布的影响,更好地实现了对系统变换效率的估算,对指导参数设计和功率元件选择具有重要意义。为验证理论分析的可靠性,对由不同半导体器件组成的1 kW实验样机进行了实验测试和分析对比。实验结果表明,所述方法在高频工况下有更高的估算精度,计算效率为97.32%,相应实验效率为96.1%。

To more accurately estimate the converter efficiency under high-frequency conditions , based on a 400 kHz high-frequency dual-Buck inverter , a loss distribution analysis method suitable for high-frequency converters is proposed in this paper. According to the analysis of the switching process , the switching loss and conduction loss of switch tube and diode are estimated in detail , and the magnetic loss is estimated based on inductance hysteresis loop. At the same time , the capacitance loss at high frequency is also considered. This method fully takes account of the influence of high-frequency working conditions on the loss distribution of the converter , and achieves better estimation of the sys? tem ' s transformation efficiency , which is significant for guiding the parameter design and power element selection. Finally , to verify the reliability of theoretical analysis , tests and comparative analysis were conducted on a 1 kW experimental prototype composed by different semiconductor components. Experimental results showed that the proposed method had a higher estimation accuracy under high-frequency working conditions;the calculation efficiency was 97.32 %, while the corresponding experimental efficiency reached 96.1 %.