Methods and system for starting an engine

Patent metadata

Field	Value
Publication number	US-10384665-B1
Application number	US-201815922731-A
Country	US
Kind code	B1
Filing date	Mar 15, 2018
Priority date	Mar 15, 2018
Publication date	Aug 20, 2019
Grant date	Aug 20, 2019

Abstract

Systems and methods for operating a hybrid powertrain or driveline that includes an engine and an integrated starter/generator are described. In one example, a clutch is positioned between the engine and the integrated starter/generator to reduce the possibility of the integrated starter/generator exceeding a rated speed of the integrated starter/generator.

First claim

The invention claimed is:

1. A powertrain operating method, comprising:
closing a belt integrated starter/generator control clutch via a controller in response to a torque of a belt integrated starter/generator not being equal to zero and a belt integrated starter/generator speed being less than a threshold speed; and
opening the belt integrated starter/generator control clutch via the controller in response to the torque of the belt integrated starter/generator being equal to zero or the belt integrated starter/generator speed being greater than the threshold speed.

2. The method of claim 1 , where the belt integrated starter/generator control clutch is positioned between an engine crankshaft and an engine pulley.

3. The method of claim 1 , where the belt integrated starter/generator control clutch is positioned between a belt integrated starter/generator shaft and a belt integrated starter/generator pulley.

4. The method of claim 1 , further comprising determining that the belt integrated starter/generator speed is greater than the threshold speed via multiplying engine speed by a pulley ratio.

5. The method of claim 1 , further comprising closing the belt integrated starter/generator control clutch during starting of an engine.

6. The method of claim 1 , where the torque of the belt integrated starter/generator is zero when battery charging via the belt integrated starter/generator is not requested and when propulsion torque is not provided via the belt integrated starter/generator.

7. The method of claim 1 , where the torque of the belt integrated starter/generator is not zero when the belt integrated starter/generator is charging a battery or when the belt integrated starter/generator is providing a propulsion torque.

8. The method of claim 1 , further comprising charging a battery via the belt integrated starter/generator when the torque of the belt integrated starter/generator is not zero.

9. A powertrain operating method, comprising:
closing a belt integrated starter/generator control clutch via a controller in response to a torque of a belt integrated starter/generator not being equal to zero and a belt integrated starter/generator speed being less than a threshold speed;
opening the belt integrated starter/generator control clutch via the controller in response to the torque of the belt integrated starter/generator being equal to zero or the belt integrated starter/generator speed being greater than the threshold speed; and
preventing engine speed from exceeding the threshold speed via the controller in response to degradation of the belt integrated starter/generator control clutch.

10. The method of claim 9 , where preventing engine speed from exceeding the threshold speed includes adjusting engine air flow via a throttle.

11. The method of claim 9 , where preventing engine speed from exceeding the threshold speed includes adjusting engine fuel flow via a fuel injector.

12. The method of claim 9 , further comprising cranking an engine via the belt integrated starter/generator when the belt integrated starter/generator control clutch is not degraded.

13. The method of claim 12 , further comprising cranking the engine via a starter motor other than the belt integrated starter/generator when the belt integrated starter/generator control clutch is degraded.

14. The method of claim 9 , further comprising decreasing output torque of the belt integrated starter/generator in response to speed of the belt integrated starter/generator being within a predetermined speed of the threshold speed.

15. A system, comprising:
an engine;
a belt integrated starter/generator coupled to the engine via a belt;
a clutch configured to selectively couple a shaft of the belt integrated starter/generator to a shaft of the engine; and
a controller including executable instructions stored in non-transitory memory to close the clutch via the controller in response to output torque of the belt integrated starter/generator not being equal to zero and speed of the belt integrated starter/generator being less than a threshold speed.

16. The system of claim 15 , further comprising additional instructions to open the clutch via the controller in response to output torque of the belt integrated starter/generator being equal to zero or belt integrated starter/generator speed being greater than the threshold speed.

17. The system of claim 15 , further comprising additional instructions to reduce output torque of the belt integrated starter/generator in response to speed of the belt integrated starter/generator being within a predetermined speed of the threshold speed when the clutch is closed.

18. The system of claim 15 , further comprising additional instructions to adjust speed of the belt integrated starter/generator to a speed of the engine multiplied by a pulley ratio before closing the clutch.

19. The system of claim 15 , further comprising additional instructions to limit speed of the engine to less than a belt integrated starter/generator rated speed in response to degradation of the clutch.

20. The system of claim 15 , further comprising a starter and additional instructions to crank the engine via the starter during starting of the engine in response to degradation of the clutch.

Assignees

• Ford Global Tech Llc

Inventors

• Boyko Anthony
• Powell Stephen
• Loveall Seth

Classifications

• B60W2510/083

  Torque · CPC title

• B60W2510/081

  Speed · CPC title

• B60W30/1846

  Preventing of breakage of drive line components, e.g. parts of the gearing · CPC title

• B60W20/00

  Control systems specially adapted for hybrid vehicles {(hybrid vehicle design, B60K6/00; electric vehicles B60L)} · CPC title

• B60K6/48

  Parallel type · CPC title