Variable precharge timing

Patent metadata

Field	Value
Publication number	US-9713965-B2
Application number	US-201414279875-A
Country	US
Kind code	B2
Filing date	May 16, 2014
Priority date	May 16, 2014
Publication date	Jul 25, 2017
Grant date	Jul 25, 2017

Abstract

An example method includes intentionally precharging a powertrain of an electric vehicle for an first time period that is different than a second precharge time period. An example electric vehicle assembly includes a precharge contactor transitionable back and forth between an open state and a closed state, a first main contactor, a second main contactor, and a controller configured to selectively close the second main contactor after the precharge contactor has been closed for a first time period that is different than a second precharge time period.

First claim

We claim:

1. A method of precharging a powertrain, comprising:
intentionally precharging a powertrain of an electric vehicle through a precharge contactor for a first time period that is different than a second baseline precharge time period for precharging the precharge contactor, wherein the first time period is greater than the second baseline precharge time period.

2. The method of claim 1 , wherein the first time period is a time period that is adjusted from the second, baseline precharge time period.

3. The method of claim 1 , further comprising intentionally precharging for the first time period rather than the second, baseline precharge time period in response to the electric vehicle starting remotely rather than not starting remotely.

4. The method of claim 1 , further comprising intentionally precharging for the first time period rather than the second, baseline precharge time period in response to the electric vehicle being unoccupied rather than occupied.

5. The method of claim 1 , further comprising intentionally precharging for the first time period rather than the second, baseline precharge time period in response to the electric vehicle charging.

6. The method of claim 1 , further comprising stopping the precharging after both expiration of the first time period and a voltage differential falling below a threshold value.

7. The method of claim 6 , wherein the voltage differential is a voltage differential across a main contactor.

8. The method of claim 1 , wherein the first time period is used rather than the second, baseline precharge time period in response to at least one step in a start sequence completing before an allotted maximum time for the at least one step.

9. The method of claim 8 , wherein the second, baseline precharge time period is an increase of the first time period by an amount corresponding to a difference between the allotted maximum time for the at least one step and an actual time for the at least one step.

10. The method of claim 8 , wherein the at least one step includes at least a primary contactor close command step, a primary contactor closing step, a precharge contactor close command step, and a precharge contactor closing step.

11. The method of claim 1 , wherein the time spent precharging changes an in-rush current to the powertrain, the in-rush current from a battery of the electric vehicle having the precharge contactor.

12. An electric vehicle precharge assembly, comprises: a precharge contactor transitionable back and forth between an open state and a closed state; and a controller configured to selectively keep the precharge contactor in the closed state for an first time period that is different than a second baseline precharge time period for the precharge contactor, wherein the first time period is greater than the second baseline precharge time period.

13. The assembly of claim 12 , wherein the controller keeps the precharge contactor in the closed state for the first time period in response to the electric vehicle starting remotely rather than not starting remotely.

14. The assembly of claim 12 , wherein the controller is configured to transition a main contactor to a closed state after the first time period ends and a voltage differential falls below a threshold value, the main contactor in the closed state causing current to move through the main contactor rather than the precharge contactor.

15. The assembly of claim 12 , wherein the first time period is used rather than the second, baseline precharge time period when at least one step in a start sequence completes before an allotted maximum time for the at least one step, wherein the first time period is greater than the second, baseline precharge time period by an amount representing a difference between the allotted maximum time for the at least one step and an actual time to complete the at least one step.

16. The assembly of claim 12 , wherein the time spent precharging changes an in-rush current to a powertrain of the electric vehicle, the in-rush current provided by a battery of the electric vehicle.

17. The assembly of claim 12 , including a battery of the electric vehicle, a first main contactor having a first polarity and a second main contactor having a second polarity opposite the first polarity, wherein the controller is configured to transition the precharge contactor to the closed state to move current through the precharge contactor when the first main contactor is in a closed state and the second main contactor is in an open state.

18. The assembly of claim 17 , wherein the controller is configured to transition the second main contactor to the closed state in response to a delta voltage across the second main contactor that is less than a certain value.

19. The assembly of claim 17 , wherein a circuit between a battery and a motor is complete when the precharge contactor and the first main contactor are in a closed state, or when the first main contactor and the second main contactor are in the closed state.

20. The assembly of claim 12 , wherein the controller is a battery electric control module.

Assignees

• Ford Global Tech Llc

Inventors

• Burkman Wesley Edward
• Skaff Ryan J
• Lovett Karin
• Bolger Bryan Michael

Classifications

• B60L2240/441

  Speed · CPC title

• B60L2240/443

  Torque · CPC title

• H01M10/42

  Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells (H01M10/60 takes precedence) · CPC title

• B60L2240/12

  Speed · CPC title

• B60L15/20

  for control of the vehicle or its driving motor to achieve a desired performance, e.g. speed, torque, programmed variation of speed · CPC title