New Start-up Strategy for Dual-Active Bridge (DAB) Converter with Reduced Start-up Time

This study proposes a new start-up strategy to reduce start-up time. The conventional strategy uses a zero-voltage sequence to reduce inrush current and employs two modulations to reduce start-up time. This strategy has low conduction losses, but it suffers from large switching losses with MOSFETs and a long start-up time, which affect reliability. The proposed strategy can reduce start-up time by employing equivalent ZVS current modulation extended-phase shift (EZM-EPS) instead of triple-phase shift modulation (TPS). The proposed strategy can achieve a fast start-up, and the feasibility of its use is verified using a 600 W prototype under 100 V input and 100 V output conditions.