基于隔离型双有源桥DC-DC变换器的三变量快速暂态电流控制

Fast Transient Current Control for Isolated Dual-active-bridge DC-DC Converters with Three Control Variables

基于双有源桥式DAB(dual active bridge)DC-DC变换器提出了一种快速暂态电流控制策略,该控制策略具有3个控制变量。当负载或传输功率指令发生突变时,暂态快速电流控制策略能改善变换器的动态特性,在一个开关周期内使电感电流快速达到新的稳态,并能有效减小暂态过程中电感电流的直流偏置,防止变压器磁饱和。另外,使用叠加定理分析了DAB的稳态和暂态特性,根据分析结果,所提快速暂态电流快速控制策略能在1个开关周期内让变换器从一个稳态到另一稳态。最后,搭建功率等级为300 W的实验平台,通过实验验证了理论分析的正确性。

In this paper, a fast transient current control ( FTCC ) strategy with three control variables is presented for dual active bridge ( DAB ) DC-DC converters. When load or the transmission power reference changes, the proposed control strategy can improve the converter ’ s dynamic behavior, which enables the inductance current achieve a new steadystate and effectively reduces the DC bias in the transient process within one switching period, hence preventing transformer saturation. In addition, the superposition theorem is used to analyze the steady-and transient-state behaviors of the DAB converter. According to the analysis results, it is shown that the proposed FTCC strategy can enable the converter to switch from one steady-state to another within one switching period. Finally, a 300 W experimental platform was built, and the theoretical analysis was verified by experimental results.