Which device provides low voltage for accessories and recharges the auxiliary battery from the high-voltage system?

Which device provides low voltage for accessories and recharges the auxiliary battery from the high-voltage system?

• A. DC/DC converter
• B. Onboard charger
• C. Inverter
• D. Battery management system

Answer: (A)

In EVs, the high-voltage traction battery powers the drivetrain, while most accessories and control electronics run on a low, 12-volt system. The device that makes this possible is the DC/DC converter. It steps down the high voltage from the traction pack to a safe 12V level to power lights, infotainment, sensors, and other accessories, and it can recharge the auxiliary 12V battery from the high-voltage system as needed. The onboard charger is used to charge the high-voltage traction battery from an external power source, not to supply the 12V system directly. The inverter has the job of converting DC from the high-voltage pack into AC for the motors (and can power some AC loads), but it isn’t responsible for providing low-voltage power to the 12V system. The battery management system monitors the state and health of the HV battery, ensuring safe operation, rather than supplying low-voltage power.

In EVs, the high-voltage traction battery powers the drivetrain, while most accessories and control electronics run on a low, 12-volt system. The device that makes this possible is the DC/DC converter. It steps down the high voltage from the traction pack to a safe 12V level to power lights, infotainment, sensors, and other accessories, and it can recharge the auxiliary 12V battery from the high-voltage system as needed.

The onboard charger is used to charge the high-voltage traction battery from an external power source, not to supply the 12V system directly. The inverter has the job of converting DC from the high-voltage pack into AC for the motors (and can power some AC loads), but it isn’t responsible for providing low-voltage power to the 12V system. The battery management system monitors the state and health of the HV battery, ensuring safe operation, rather than supplying low-voltage power.