高频高效的LLC谐振变换器研究

Research on high frequency and high efficiency LLC resonant converter

随着开关频率的提高,LLC谐振变换器中开关损耗会随之增加。将具有高频特性的氮化镓(GaN)器件结合平面变压器和同步整流技术应用于LLC谐振变换器中,实现开关频率和效率的双重提高。首先分析了LLC谐振变换器的工作原理,之后以减小损耗为目标,对谐振元件参数进行设计。在此基础上建立了两套对照实验,计算了两个实验中功率管、变压器和整流管中的损耗,最后搭建两个实验样机平台。相关实验表明:效率提高11.25%,验证了所设计方案的合理性。

With the increase of switching frequency, the switching loss in LLC resonant converter will increase. Gallium nitride(GaN) device with high frequency characteristics is applied to LLC resonant converter with planar transformer and synchronous rectifier technology to achieve the double improvement of switching frequency and efficiency. Firstly, the working principle of LLC resonant converter was analyzed. Then, the resonant element parameters were designed to reduce the loss. On this basis, two sets of control experiments were established, and the losses in the power tube, transformer and rectifier tube in the two experiments were calculated. Finally, two experimental prototype platforms were built. Relevant experiments show that the efficiency is increased by 11.25%, which verifies the rationality of the design scheme.