Deceleration control system for a hybrid vehicle

Patent metadata

Field	Value
Publication number	US-9738268-B1
Application number	US-201615050776-A
Country	US
Kind code	B1
Filing date	Feb 23, 2016
Priority date	Feb 23, 2016
Publication date	Aug 22, 2017
Grant date	Aug 22, 2017

Abstract

A vehicle control system includes a controller that is programmed to, in response to an accelerator lift-pedal event, generate a drag torque, with at least one of an engine and electric machine, having a magnitude that is based on a deceleration fuel shut-off torque of the engine and a desired power output of the electric machine, and limit the drag torque to a threshold value that is based on the deceleration fuel shut-off torque.

First claim

What is claimed is:

1. A vehicle control system comprising:
a controller programmed to, in response to an accelerator lift-pedal event, generate a drag torque, with at least one of an engine and electric machine, having a magnitude that is based on a deceleration fuel shut-off torque of the engine and a desired power output of the electric machine, and limit the drag torque to a threshold value that is based on the deceleration fuel shut-off torque.

2. The system of claim 1 , wherein the desired power output is based on a desired charging power to recharge a traction battery.

3. The system of claim 2 , wherein the desired power output is based on a desired operating power to operate at least one vehicle accessory.

4. The system of claim 3 , wherein the controller is further programmed to limit the drag torque such that the electric machine does not produce the desired power output.

5. The system of claim 3 , wherein the at least one vehicle accessory is an air conditioning system.

6. The system of claim 3 , wherein the at least one vehicle accessory is a power steering system.

7. The system of claim 1 , wherein the controller is further programmed to limit the drag torque while a speed of the vehicle is greater than a first threshold speed.

8. The system of claim 7 , wherein the controller is further programmed to decrease the drag torque at a rate that depends on whether a speed of the vehicle is less than a second threshold speed.

9. A vehicle control system comprising:
a controller programmed to, in response to a commanded magnitude of drag torque, that (i) results from an accelerator lift-pedal event and (ii) is based on an engine fuel shut-off torque and a generator torque required to produce a desired amount of electrical power, exceeding a threshold that is based on the engine fuel shut-off torque, generate an actual drag torque having a magnitude that does not exceed the threshold such that the generator torque produces less than the desired amount of electrical power.

10. The system of claim 9 , wherein the desired amount of electrical power is based on a desired charging power to recharge a traction battery.

11. The system of claim 9 , wherein the desired amount of electrical power is based on a desired operating power to operate at least one vehicle accessory.

12. The system of claim 11 , wherein the at least one vehicle accessory is an air condition system.

13. The system of claim 11 , wherein the at least one vehicle accessory is a power steering system.

14. A vehicle comprising:
an engine and generator respectively configured to, in response to an accelerator pedal lift-off event, produce a fuel shut-off torque and produce a drag torque; and
a controller programmed to, in response to a sum of the fuel shut-off torque and drag torque exceeding a threshold, limit the drag torque such that the generator generates an amount of electrical power less than a desired amount of electrical power.

15. The vehicle of claim 14 , wherein the desired amount of electrical power is based on a desired charging power to recharge a traction battery.

16. The vehicle of claim 15 , wherein the desired amount of electrical power is based on a desired operating power to operate at least one vehicle accessory.

17. The vehicle of claim 16 , wherein the at least one vehicle accessory is an air conditioning system.

18. The vehicle of claim 16 , wherein the at least one vehicle accessory is a power steering system.

Assignees

• Ford Global Tech Llc

Inventors

• Zhang Chen
• Johri Rajit
• Thompson Scott James
• Kuang Ming Lang
• Doering Jeffrey Allen
• Boesch Mathew Alan
• Gabriel David Crist

Classifications

• B60Y2200/92

  Hybrid vehicles · CPC title

• B60Y2300/18125

  Regenerative braking · CPC title

• B60Y2300/43

  Control of engines · CPC title

• Y10S903/904

  Component specially adapted for hev · CPC title

• B60K6/22

  characterised by apparatus, components or means specially adapted for HEVs · CPC title