A Single-Stage On-Board Charger With Integrated Power Decoupling

In this letter, a universal single-stage on-board charger (OBC) topology is proposed to support a single-phase AC grid without additional power decoupling (PD) circuits. The converter can control not only power transfer but also PD with only additional capacitor. For an integrated decoupling operation, a novel switching modulation scheme derived from the single-stage dual active bridge (DAB) with PD analysis is also easy to implement. In addition, the decoupling capacitor is designed by considering both PD and ZVS operation to ensure efficient full-range operation. The proposed topology has been verified by experimental results for a 6.4 kW modular prototype. A peak efficiency of 96.6% was achieved at a full load condition. The current total harmonic distortion (THD) is lower than 5%.