基于三角电流模式的双有源桥变换器

Research on Double Active Bridge Converter Based on Triangular Current Mode

采用传统移相控制双有源桥无法实现开关管的零电流关断,使得应用在大功率场合下的IGBT关断损耗过大,同时存在功率回流的问题。为了减少开关管的关断损耗和变换器的功率回流,提高系统效率,提出三角电流模式双有源桥的控制方法。通过对传统移相控制进行分析,解释双有源桥的基本工作原理,并与三角电流模式的控制方法进行性能比较;分别分析三角电流模式双有源桥正向工作和反向工作时的开关时序和工作模态,以及变换器软开关的实现原理,推导出系统传输功率的计算公式和电路元件的参数优化方法;最后通过仿真和实验证明该控制方法的可行性。

In view of the fact that the traditional phase-shifted double active bridge circuit can not realize zero-current switching-off of switching transistors, which leads to excessive switching loss of IGBT in high-power applications, and also the problem of power reflux. In order to reduce the switching-off loss and power return, thereby improving the efficiency of the system, this paper proposes a control method of triangular current mode dual active bridge. Through a brief analysis of traditional phase-shifting control, the basic working principle of double active bridge is explained, and its performance is compared with that of triangular current mode control method. The switching time sequence of forward and reverse operation of double active bridge in triangular current mode is given respectively. The working process of converter and the principle of soft switching are analyzed in detail. The calculation formula of system transmission power and the parameter optimization method of circuit elements are deduced. Finally, the feasibility of the control method is verified by simulation and experiment.