Generic Dynamic Phase-Shift Control for Bidirectional Dual-Active Bridge Converters

Abstract

This letter proposes a generic method to model and mitigate the transient dc bias in the transformer winding current and the magnetizing flux linkage of the dual-active bridge (DAB) converter, which is valid for all the most commonly used modulation methods such as single phase-shift, extended phase-shift, dual phase-shift, and triple phase-shift. By performing a simple dynamic volt-seconds balancing in each half-bridge independently, the transformer winding current and the magnetizing flux linkage can reach any new reference steady state in half-switching cycle simultaneously with significantly suppressed transient dc-bias components. More importantly, this excellent dynamic performance can be realized for any modulation mode transition, regardless of the dc voltage ratio and the power direction change. Comprehensive simulations and experiments are performed to validate the effectiveness of the proposed control method.