宽电压增益范围双向CLL谐振变换器研究

Research on bidirectional CLL resonant converter with wide voltage gain range

双向CLL谐振变换器在变频或移相控制下均为窄电压增益范围。为了实现双向CLL谐振变换器在开关频率小范围变化的同时具有宽电压增益范围,详细分析了变频和移相控制方式下双向CLL谐振变换器的工作原理、变频及移相控制的优缺点,提出了一种变频升压、移相降压的混合控制方法。在该控制策略下,不仅实现了变换器双向工作时稳定输出,还实现了良好的升降压能力和软开关特性。最后设计了一台500 W的实验样机验证混合控制下双向CLL谐振变换器的性能。实验结果验证了混合控制策略的可行性和变换器升降压能力的优越性。

The bidirectional CLL resonant converter has the disadvantage of narrow voltage gain range under variable frequency or phase shift control.In order to realize that the bidirectional CLL resonant converter has a wide voltage gain range while the switching frequency changes in a small range,this paper analyzes the working principle of the bidirectional CLL resonant converter under the variable frequency and phase shift control modes.Based on the advantages and disadvantages of variable frequency and phase shift control,a hybrid control method of variable frequency boosting and phase shifting bucking is proposed.Under this control strategy,the converter not only achieves stable output in bidirectional operation,but also achieves great buck-boost capability and soft-switching characteristics.Finally,a 500 W experimental prototype is designed to verify the performance of the bidirectional CLL resonant converter under hybrid control.The experimental results verify the feasibility of the converter control strategy and the superiority of the buck-boost capability.