【摘要】 作为固态变压器中的核心部件,大功率隔离型双向直流变换器的效率优化至关重要。通过分析双移相桥式隔离型直流变换器的工作原理,详细计算了包括中频变压器在内的直流变换器损耗分布,得出直流变换器的损耗分布结果,用以指导直流变换器的效率优化。基于损耗分析结果,为提高直流变换器的效率,研究一种基于模式切换的控制方式,从而实现了全功率范围内的损耗更优控制。最后,搭建额定容量为35k W的实验样机,实现了本文所述的控制方式,不同漏感条件下样机的实测效率为98.1%和97.6%,验证了损耗分析及控制算法的正确性。更多还原

【Abstract】 As a core component of solid-state transformer, the efficiency of high power isolated bi-directional DC-DC converter is very important. This paper describes the principles of dual active bridge(DAB) in detail, and expressions of dissipated power are obtained in order to predict the different components losses. Moreover, this paper presents a novel control method based on alternative modulation mode to achieve higher efficiency. Then a prototype converter with rated power 35 k W is implemented to verify the power loss prediction and control method. The values of measured efficiency are 98.1% and 97.6% respectively with different leakage reluctances.更多还原