Research on Bench‑Test Technology for Board‑level Repaired On‑Board Charger

Abstract

Aiming at the risks such as power‑device burnout upon power‑on and abnormal charging caused by direct vehicle‑mounting of latent board‑level faults after board‑level repair of the On‑Board Charger (OBC), this paper proposes a maintenance quality‑control scheme of “off‑board pre‑test — hierarchical bench verification — quantitative delivery evaluation”. Taking a 6.6 kW VAILD‑series on‑board charger manufactured by VMAX as the research object, a bench‑test platform consisting of a low‑voltage DC power supply, CAN communication module, AC analog source and high‑voltage measurement unit is constructed. A hierarchical test workflow covering low‑voltage pre‑diagnosis, no‑load functional verification and protection‑boundary spot‑check is established, alongside a quantitative delivery‑index system centered on insulation resistance, PFC bus voltage, DC/DC output voltage and whole‑unit static current. Engineering verification shows that the proposed hierarchical bench‑verification scheme can effectively identify residual board‑level repair defects without vehicle‑mount conditions and avoid secondary damage to power devices, which provides a reproducible engineering method for reliability evaluation of board‑level‑repaired OBC.