On-board chargers (OBCs) face challenges from bulky DC-link electrolytic capacitors, oversized isolation transformers, and efficiency loss in the isolated DC/DC stage over wide battery voltage ranges. Conventional active power decoupling (APD) circuits can reduce DC-link capacitance requirements. However, they typically rely on additional external switches and energy storage components dedicated to a single function. To improve, this work introduces a two-stage 800 V OBC architecture with reduced DC-link capacitance via embedded active power decoupling. The proposed design employs an integrated APD unit, thereby lowering capacitance demand, minimizing transformer volume, and enhancing the performance of the isolated DC/DC stage under wide gain conditions. A 3.3 kW prototype, supporting an output voltage range of 600–900 V, achieves a peak full-load efficiency of 95.96%, while consistently maintaining high performance across the entire operating range.
.jpg "Haoyu Wang (he/him/his) photo")