Methods and systems for operating a vehicle driveline

• US 9,358,972 B2
• Filed: 11/13/2014
• Issued: 06/07/2016
• Est. Priority Date: 05/04/2012
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Reed, Dennis Craig, Gibson, Alex O'Connor, Doering, Jeffrey Allen, Banker, Adam Nathan, Lee, Seung-Hoon
• Primary Examiner(s): ARTHUR JEANGLAUD, GERTRUDE
• Application Number:
  US14/540,913
• Publication Number:
  US 20150072832A1
• Time in Patent Office: 572 Days
• Field of Search: 701/22, 903/902, 477/3, 180/65.265
• US Class Current: 1/1
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• CPC Class Codes: B60W 10/023 Fluid clutches
• CPC Class Codes: B60W 10/026 of lock-up clutches
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 20/10 Controlling the power contribution of each of the prime movers to meet required power demand
• CPC Class Codes: B60W 20/15 Control strategies specially adapted for achieving a particular effect
• CPC Class Codes: B60W 20/40 Controlling the engagement or disengagement of prime movers, e.g. for transition between prime movers power-up or power-down of the driveline B60W30/192
• CPC Class Codes: B60W 2030/1809 Without torque flow between driveshaft and engine, e.g. with clutch disengaged or transmission in neutral
• CPC Class Codes: B60W 2030/206 related or induced by the engine
• CPC Class Codes: B60W 30/18118 Hill holding
• CPC Class Codes: B60W 30/18127 Regenerative braking
• CPC Class Codes: B60W 30/20 Reducing vibrations in the driveline
• CPC Class Codes: F02D 41/0032 Controlling the purging of the canister as a function of the engine operating conditions
• CPC Class Codes: F02P 5/1508 with particular means during idling
• CPC Class Codes: Y02T 10/40 Engine management systems
• CPC Class Codes: Y02T 10/60 Other road transportation technologies with climate change mitigation effect
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y10S 903/902 Prime movers comprising electrical and internal combustion motors
• CPC Class Codes: Y10S 903/93 : Conjoint control of different elements
• CPC Class Codes: Y10S 903/947 : Characterized by control of braking, e.g. blending of regeneration, friction braking

Abstract

Systems and methods for improving operation of a hybrid vehicle are presented. In one example, an engine is accelerated to a speed of a driveline integrated starter/generator before the engine is coupled to the driveline integrated starter/generator. Further, a driveline disconnect clutch application force is adjusted in response to torque of the driveline integrated starter/generator and a torque converter torque.

Claims

1. A driveline operating method, comprising:

providing a positive torque to a driveline via a driveline integrated starter/generator (DISG) responding to driver demand torque;

operating an engine at an idle speed in a speed control mode while providing the positive torque to the driveline via the DISG;

accelerating the engine from the idle speed in the speed control mode to DISG speed in response to a desired torque; and

adjusting application force of a driveline disconnect clutch in response to a driveline disconnect clutch torque estimate based on torque converter torque and DISG torque.

2. The method of claim 1, where the driveline disconnect clutch torque estimate is further based on a torque converter impeller inertia.

3. The method of claim 1, where the driveline disconnect clutch torque estimate is further based on a torque converter impeller acceleration.

4. The method of claim 1, where the idle speed is a sailing mode idle speed.

5. The method of claim 4, where the sailing mode idle speed is a lower speed than a base engine idle speed.

6. The method of claim 5, further comprising advancing engine spark timing while the engine operates in the sailing mode idle speed with respect to engine spark timing of the engine while operating the engine at the base engine idle speed.

7. The method of claim 6, further comprising reducing an engine air amount while the engine operates in the sailing mode idle speed with respect to engine air amount while operating the engine at the base engine idle speed.

8. A driveline operating method, comprising:

providing positive torque to a driveline via a driveline integrated starter/generator;

operating an engine at an idle speed in a speed control mode;

adjusting torque converter clutch slip and accelerating the engine in the speed control mode to driveline integrated starter/generator speed in response to a desired torque;

closing a driveline disconnect clutch in response to engine speed substantially matching driveline integrated starter/generator speed, where closing the driveline disconnect clutch includes incrementally increasing a driveline disconnect clutch application command;

adjusting a transfer function of the driveline disconnect clutch in response to incrementally increasing the driveline disconnect clutch application command, a driveline disconnect clutch torque estimate that is based on a torque converter torque, and a driveline integrated starter/generator torque; and

operating the driveline disconnect clutch in response to the transfer function.

9. The method of claim 8, where the transfer function is adjusted based on a difference between a value of the transfer function and a torque estimate based on the driveline disconnect clutch torque estimate that is based on torque converter torque, and the driveline integrated starter/generator torque.

10. The method of claim 9, where the driveline integrated starter/generator torque is estimated based on a current.

11. The method of claim 8, where the idle speed is a sailing mode idle speed.

12. The method of claim 11, where the sailing mode idle speed is a lower speed than a base engine idle speed.

13. The method of claim 8, where the desired torque is increasing.

14. The method of claim 13, where the desired torque increases to a torque greater than a threshold driveline integrated starter/generator torque.

15. A vehicle system, comprising:

an engine;

a dual mass flywheel including a first side mechanically coupled to the engine;

a driveline disconnect clutch mechanically including a first side coupled to a second side of the dual mass flywheel;

a driveline integrated starter/generator (DISG) including a first side coupled to a second side of the driveline disconnect clutch;

a transmission selectively coupled to the engine via the driveline disconnect clutch; and

a controller including executable instructions stored in non-transitory memory to solely provide positive torque to the transmission via the DISG in response to a desired torque being less than an engine cranking torque, instructions for adjusting engine speed to follow DISG speed when DISG torque is greater than the engine cranking torque and less than a threshold DISG torque, and instructions for adapting a transfer function of the driveline disconnect clutch.

16. The vehicle system of claim 15, further comprising additional instructions to close the driveline disconnect clutch when engine speed is substantially equal to DISG speed, and where the transfer function is adjusted based on closing the driveline disconnect clutch.

17. The vehicle system of claim 16, further comprising additional instructions to operate the engine in a torque control mode after closing the driveline disconnect clutch.

18. The vehicle system of claim 17, further comprising additional instructions to operate the engine in a speed control mode while adjusting engine speed to follow DISG speed.

19. The vehicle system of claim 18, further comprising additional instructions to provide the desired torque via the engine and the DISG.

20. The vehicle system of claim 15, further comprising a torque converter and torque converter clutch, and further comprising additional instructions to increase torque converter clutch slip in response to the desired torque.