输入电压波动下宽增益谐振变换器优化设计

Optimal design of wide gain resonant converter under input voltage fluctuation

该文设计了一种全桥-半桥模态切换的宽增益谐振变换器:首先,通过优化谐振腔结构,在电流传输中引入三次谐波,减小能量循环及开关管损耗;然后,根据输入电压控制变换器在两种不同模态切换,拓宽增益范围,使得变换器具有更灵活的调压特性;最后,利用基波近似法推导电压增益并绘制增益曲线仿真图,分析谐振参数对电压增益的影响并设计合适的参数,运用变频控制优化输出波形,实现变换器在不同模态下的电压平稳输出。通过搭建实验样机展开实验分析,结果显示不同模态下变换器均能实现软开关,增益拓宽且输出效率明显提升。

In this paper,a wide-gain resonant converter with full-bridge to half-bridge mode switching is designed.By optimizing the resonant cavity structure,the third harmonic is introduced into the current transmission to reduce the energy cycle and switch losses,and then the converter is controlled to switch in two different modes according to the input voltage to broaden the gain range,so that the converter has more flexible voltage regulation characteristics.The fundamental approximation method is used to derive the voltage gain,draw the gain curve simulation diagram,analyze the influence of resonance parameters on the voltage gain,and design appropriate parameters.The frequency conversion control is used to optimize the output waveform to achieve stable voltage output of the converter under different modes.The experimental results show that the converter can achieve soft switching under different modes,and the gain is broadened and the output efficiency is significantly improved.