Onboard Charger (OBC) refers to the charger fixed on the electric vehicle, which has the ability to charge the electric vehicle power battery safely and automatically. According to the data provided by the battery management system (BMS), the charger can dynamically adjust the charging current or voltage parameters and perform the corresponding actions. Charging process. By rectifying and filtering, AC is converted into DC, thus realizing a kind of on-board power supply product for charging electric vehicle power battery. There are passenger cars, logistics vehicles, light trucks, buses and so on.