New Combined OBC and LDC System for Electric Vehicles With 800 V Battery
Dae-Woo Lee, Bom-Seok Lee, Jae-Hyun Ahn, Ji‐Yeon Kim, Jae-Kuk Kim
Abstract
This article proposes a new vehicle charging system (VCS) that combines an on-board charger (OBC) and a low-voltage dc–dc converter (LDC) for electric vehicles with an 800 V battery system. The proposed VCS improves the power density by integrating the LDC and OBC transformers and the LDC primary and OBC secondary components. Moreover, a new method is proposed for reducing the voltage to limit the high voltage generated in the link capacitor due to the multiwinding transformer. Furthermore, the proposed converter can simultaneously charge an auxiliary battery and a main battery. To confirm the validity of the proposed converter, a prototype rated with 3.3 kW OBC and 1.8 kW LDC is analyzed and the operating characteristics are described.