Plug-In Vehicle with Secondary DC-DC Converter

• US 20150097527A1
• Filed: 10/09/2013
• Published: 04/09/2015
• Est. Priority Date: 10/09/2013
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: DeDona, Matthew Roger, Rutyna, Arthur M., Ferrel, Mark J., Wu, Bo, Heremans, Hilde Anne, Bell, Christopher W.
• Granted Patent: US 9,969,276 B2
• Time in Patent Office: Days
• US Class Current: 320/109
• CPC Class Codes: B60L 1/00 Supplying electric power to auxiliary equipment of vehicles circuit arrangements for charging batteries H02J7/00
• CPC Class Codes: B60L 2210/12 Buck converters
• CPC Class Codes: B60L 2210/30 AC to DC converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2240/34 Cabin temperature
• CPC Class Codes: B60L 2240/80 Time limits
• CPC Class Codes: B60L 2260/56 Temperature prediction, e.g. for pre-cooling
• CPC Class Codes: B60L 2270/20 Inrush current reduction, i.e. avoiding high currents when connecting the battery
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/66 Arrangements of batteries
• CPC Class Codes: B60L 53/16 Connectors, e.g. plugs or sockets, specially adapted for charging electric vehicles
• CPC Class Codes: B60L 53/18 Cables specially adapted for charging electric vehicles
• CPC Class Codes: B60L 58/20 having different nominal voltages
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility
• CPC Class Codes: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles

Abstract

A vehicle includes a traction battery, an auxiliary battery, a charger, and two DC-DC converters. A first DC-DC converter is connected between the traction battery and the auxiliary battery through a main contactor. A second DC-DC converter is connected between the charger and the auxiliary battery. The charger is configured to charge the auxiliary battery via the second DC-DC converter when the charger is receiving power. The second DC-DC converter is configured to charge the auxiliary battery when the first DC-DC converter is disconnected from the traction battery. The second DC-DC converter can charge the auxiliary battery independent of the charger charging the traction battery. The second DC-DC converter may be configured to generally maximize power conversion efficiency in a range of power outputs associated with charging the auxiliary battery.

Claims

1. A vehicle comprising:

a traction battery;

an auxiliary battery;

a charger;

a first DC-DC converter electrically connected with the auxiliary battery and configured to be selectively electrically connected with the traction battery; and

a second DC-DC converter electrically connected between the auxiliary battery and the charger, wherein the charger is configured to charge the auxiliary battery via the second DC-DC converter when the charger is receiving power and the first DC-DC converter is disconnected from the traction battery.

2. The vehicle of claim 1 wherein the charger is further configured to be selectively electrically connected with the traction battery.

3. The vehicle of claim 2 wherein the charger is further configured to charge the auxiliary battery via the second DC-DC converter when the charger is disconnected from the traction battery.

4. The vehicle of claim 2 wherein the charger is further configured to provide power to the first DC-DC converter when the charger is connected to the traction battery and the first DC-DC converter is connected to the traction battery.

5. The vehicle of claim 1 wherein the charger is further configured to adjust a voltage output level of the second DC-DC converter.

6. The vehicle of claim 1 wherein the charger is further configured to charge the auxiliary battery via the second DC-DC converter for a predetermined amount of time before enabling power to electrical loads connected to the auxiliary battery.

7. The vehicle of claim 1 wherein the second DC-DC converter is configured to generally maximize power conversion efficiency in a range of power outputs associated with charging the auxiliary battery.

8. A vehicle comprising:

a charger;

a first DC-DC converter switchably connected to a traction battery through a main contactor, electrically connected with an auxiliary battery, and configured to charge the auxiliary battery when the main contactor is closed; and

a second DC-DC converter, electrically connected between the auxiliary battery and a charger, configured to charge the auxiliary battery when the main contactor is open and the charger is receiving power.

9. The vehicle of claim 8 wherein the charger is switchably connected to the traction battery through a second contactor.

10. The vehicle of claim 9 wherein the second DC-DC converter is further configured to charge the auxiliary battery when the second contactor is open.

11. The vehicle of claim 9 wherein the main contactor is configured to be closed when the charger is switchably connected to the traction battery in the presence of a request for cabin pre-conditioning.

12. The vehicle of claim 8 wherein the second DC-DC converter is configured to generally maximize power conversion efficiency in a range of power outputs associated with charging the auxiliary battery.

13. A method of charging an auxiliary battery comprising:

in response to electric vehicle supply equipment (EVSE) being connected to a vehicle charge port to provide power to an on-board charger, operating, by at least one controller, a second DC-DC converter electrically connected between the auxiliary battery and the on-board charger to charge the auxiliary battery in the absence of a first DC-DC converter being switchably connected to a traction battery.

14. The method of claim 13 wherein operating the second DC-DC converter includes adjusting a voltage output level of the second DC-DC converter.

15. The method of claim 13 wherein operating the second DC-DC converter includes charging the auxiliary battery for a predetermined amount of time before activating electrical loads connected to the auxiliary battery.

16. The method of claim 13 further comprising operating the first DC-DC converter to charge the auxiliary battery when the first DC-DC converter is switchably connected to the traction battery.

17. The method of claim 13 further comprising operating the second DC-DC converter to charge the auxiliary battery when the on-board charger is not switchably connected to the traction battery.