Methods and system for reserving torque for engine starting

Patent metadata

Field	Value
Publication number	US-11619201-B1
Application number	US-202117449216-A
Country	US
Kind code	B1
Filing date	Sep 28, 2021
Priority date	Sep 28, 2021
Publication date	Apr 4, 2023
Grant date	Apr 4, 2023

Abstract

Systems and methods for operating a hybrid vehicle are described. In one example, a torque reserve for starting an engine via an electric machine is adjusted responsive to vehicle operating conditions. The torque reserve may set aside a portion of torque that an electric machine may produce for cranking and starting an engine.

First claim

The invention claimed is:

1. A method for operating a powertrain, comprising:
adjusting a torque reserve amount of an electric machine via a controller in response to a characterization of a restart of an engine after beginning engine shutdown and before stopping rotation of the engine, wherein the characterization includes partitioning the restart into one of two categories.

2. The method of claim 1 , further comprising restarting the engine via applying at least a portion of the torque reserve to rotate the engine via the electric machine.

3. The method of claim 1 , where a first of the two categories is an active category.

4. The method of claim 3 , where a second of the two categories is a passive category.

5. The method of claim 1 , further comprising adjusting the torque reserve amount in response to an urgency of the restart.

6. The method of claim 5 , where the urgency is based on a rate of driver demand pedal change.

7. A system, comprising:
an engine;
an integrated starter/generator (ISG);
a driveline disconnect clutch; and
a controller including executable instructions stored in non-transitory memory that cause the controller to adjust a torque reserve of the ISG for engine starting in response to an engine stop request.

8. The system of claim 7 , further comprising additional instructions to restart the engine in response to an increasing driver demand torque.

9. The system of claim 7 , further comprising additional instructions to adjust the torque reserve in response to a speed of the ISG.

10. The system of claim 7 , further comprising a transmission, and additional instructions to adjust the torque reserve in response to an engaged gear of the transmission.

11. The system of claim 7 , further comprising additional instructions to adjust the torque reserve in response to a vehicle drive mode.

12. The system of claim 11 , where adjusting the torque reserve in response to the vehicle drive mode includes increasing the torque reserve for a sport drive mode.

13. The system of claim 12 , further comprising additional instructions to adjust the torque reserve in response to a speed of the engine.

14. The system of claim 13 , where adjusting the torque reserve includes decreasing the torque reserve as engine speed increases.

15. A method for operating a powertrain, comprising:
adjusting a torque reserve amount for an electric machine via a controller in response to a selected engine cranking device and stages of engine starting.

16. The method of claim 15 , further comprising adjusting the torque reserve amount in response to an engine stop request.

17. The method of claim 15 , where the stages of engine starting include cranking and engine run-up.

18. The method of claim 15 , further comprising cranking an engine via the electric machine utilizing torque included in the torque reserve amount.

19. The method of claim 18 , further comprising reducing the torque reserve amount to zero in response to fully closing a driveline disconnect clutch.

Assignees

• Ford Global Tech Llc

Inventors

• Ravichandran Maruthi
• Tumu Ravikumar
• Meyer Jason
• Johri Rajit
• Doering Jeffrey Allen

Classifications

• F02N2300/2002

  using different starting modes, methods, or actuators depending on circumstances, e.g. engine temperature or component wear · CPC title

• F02N2300/104

  Control of the starter motor torque · CPC title

• F02N2200/042

  Starter torque · CPC title

• F02N2200/022

  Engine speed · CPC title

• F02N11/0844

  with means for restarting the engine directly after an engine stop request, e.g. caused by change of driver mind · CPC title