Active Selection of Current Commutation Loop for Hybrid Three-Level Dual Active Bridge DC-DC Converter with TPS Control

Abstract

Active neutral-point-clamped (ANPC) three-level dual active bridge DC-DC converter (DAB) has a good prospect in high-voltage and large-capacity applications. Different from the conventional two-level DAB, there are two alternative neutral current path in ANPC-DAB, providing the possibility to reduce the system losses by actively selecting the current commutation loops. Multi-pulse tests are implemented to compare the switching losses of different commutation loops, and the general criteria for optimizing the commutation loop are obtained. On the basis of this, the active control method for possible commutation cases with TPS control is proposed. The effectiveness of the proposed active control method is validated by experiments on a laboratory prototype.