System And Method For Vehicle Battery Charging

• US 20110163717A1
• Filed: 11/05/2010
• Published: 07/07/2011
• Est. Priority Date: 11/05/2010
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Gale, Allan Roy, Degner, Michael W., Momcilovich, Paul Theodore
• Granted Patent: US 9,827,861 B2
• Time in Patent Office: Days
• US Class Current: 320/109
• CPC Class Codes: B60L 53/14 Conductive energy transfer
• 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 90/14 Plug-in electric vehicles

Abstract

A vehicle power system includes a traction battery and a battery charger. The battery charger has an electrical output and a capacitor electrically connected with the electrical output. No more than two electrical contactors are electrically connected with the traction battery, capacitor and battery charger.

Claims

1. A vehicle power system comprising:

a traction battery;

a battery charger including (i) a power converter having an electrical output and an electrical input configured to be electrically connected with an electrical power source remote from the vehicle and (ii) a capacitor electrically connected with the electrical output; and

no more than two electrical contactors electrically connected with the traction battery, capacitor and power converter.

2. The system of claim 1 further comprising a controller configured to determine a voltage of the traction battery.

3. The system of claim 2 wherein the controller is further configured to command an output voltage from the battery charger equal to the voltage of the traction battery.

4. The system of claim 3 wherein the controller is further configured to determine whether the output voltage of the battery charger is approximately equal to the voltage of the traction battery.

5. The system of claim 4 wherein determining whether the output voltage of the battery charger is approximately equal to the voltage of the traction battery includes determining a difference between the output voltage of the battery charger and a voltage across the capacitor.

6. The system of claim 5 wherein determining whether the output voltage of the battery charger is approximately equal to the voltage of the traction battery further includes determining whether the difference is less than a predefined threshold.

7. The system of claim 4 wherein the controller is further configured to cause the contactors to close if the output voltage of the battery charger is approximately equal to the voltage of the traction battery.

8. A method for charging a traction battery of a vehicle comprising:

determining a voltage of the traction battery;

commanding an output voltage from a battery charger equal to the voltage of the traction battery;

determining whether the output voltage of the battery charger is approximately equal to the voltage of the traction battery; and

closing contactors electrically connected with the traction battery and battery charger if the output voltage of the battery charger is approximately equal to the voltage of the traction battery.

9. The method of claim 8 wherein determining whether the output voltage of the battery charger is approximately equal to the voltage of the traction battery includes determining a difference between a voltage at terminals of the traction battery and a voltage across a capacitor electrically connected with the battery charger.

10. The method of claim 9 wherein determining whether the output voltage of the battery charger is approximately equal to the voltage of the traction battery further includes determining whether the difference is less than a predefined threshold.

11. An alternatively powered vehicle comprising:

an electric machine configured to generate motive power for the vehicle;

a traction battery configured to provide electrical power to the electric machine;

a battery charger including an output and a capacitor electrically connected with the output; and

a wiring system connecting the traction battery and the output of the battery charger, the wiring system including no more than two electrical contactors.

12. The vehicle of claim 11 further comprising a controller configured to determine a voltage of the traction battery.

13. The vehicle of claim 12 wherein the controller is further configured to command an output voltage from the battery charger equal to the voltage of the traction battery.

14. The vehicle of claim 13 wherein the controller is further configured to determine whether the output voltage of the battery charger is approximately equal to the voltage of the traction battery.

15. The vehicle of claim 14 wherein determining whether the output voltage of the battery charger is approximately equal to the voltage of the traction battery includes determining a difference between the output voltage of the battery charger and a voltage across the capacitor.

16. The vehicle of claim 15 wherein determining whether the output voltage of the battery charger is approximately equal to the voltage of the traction battery further includes determining whether the difference is less than a predefined threshold.

17. The vehicle of claim 14 wherein the controller is further configured to cause the contactors to close if the output voltage of the battery charger is approximately equal to the voltage of the traction battery.