基于有源中点钳位五电平电路的双有源桥DC/DC变换器

Five-level Active Neutral Point Clamed Dual Active Bridge DC/DC Converter

采用多电平电路构建的双有源桥(dual active bridge,DAB)DC/DC变换器可适用于更高的电压等级并能显著地提高功率密度及性能。基于九开关管五电平有源中点钳位(five-level active neutral point clamed,5L ANPC)电路构建DAB变换器,消除传统的八开关管5L ANPC电路所存在的电平跳变问题。通过分析开关状态之间的切换过程,选取的零开关状态实现所有高压开关管的软开关运行;通过分析不同开关序列对飞跨电容电压和直流侧中点电压的影响,提出一种飞跨电容电压的平衡控制方法。基于1kW样机的实验结果表明,该文构建的5L ANPC DAB变换器获得了优良的性能。

By using multi-level circuits,the dual active bridge(DAB)DC/DC converter can achieve higher voltage level,higher power density and better performance.This paper firstly analyzes the dead-zone effect of the active neutral point clamed five-level(5L ANPC)circuit when used in DAB converter,then a DAB based on a nine-switch 5L ANPC circuit is proposed,where the dead time effect is eliminated by a zero state with dual current paths.On this basis,through the analysis of the switching process,the zero switching states selected in this paper realize the soft switching operation of all high-voltage power switches.Furthermore,through the analysis of the effects of different switching sequences on flying capacitor voltage and neutral point voltage,a control strategy is proposed to ensure the voltage balancing of flying capacitor.The experimental results on a 1kW experimental prototype show that the proposed 5L ANPC DAB converter achieves good performance.