Control of a rolling stop-start vehicle engine

• US 9,964,090 B2
• Filed: 07/01/2016
• Issued: 05/08/2018
• Est. Priority Date: 07/01/2016
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Khafagy, Hafiz Shafeek, Kok, Daniel Benjamin, Awadi, Ahmed, Younis, Raed, Hakeem, Mohannad
• Primary Examiner(s): Nguyen, Hung Q
• Assistant Examiner(s): Mo, Xiao
• Application Number:
  US15/200,461
• Publication Number:
  US 20180003143A1
• Time in Patent Office: 676 Days
• CPC Class Codes: B60L 1/00 Supplying electric power to auxiliary equipment of vehicles circuit arrangements for charging batteries H02J7/00
• CPC Class Codes: B60L 2240/12 Speed
• CPC Class Codes: B60L 2240/443 Torque
• CPC Class Codes: B60L 50/10 using propulsion power supplied by engine-driven generators, e.g. generators driven by combustion engines
• CPC Class Codes: B62D 5/04 electrical, e.g. using an electric servo-motor connected to, or forming part of, the steering gear
• CPC Class Codes: F02D 41/042 for stopping the engine
• CPC Class Codes: F02D 41/12 for deceleration F02D41/0005, F02D41/107 take precedence
• CPC Class Codes: F02N 11/0814 comprising means for controlling automatic idle-start-stop
• CPC Class Codes: F02N 11/0822 related to action of the driver
• CPC Class Codes: F02N 11/0862 characterised by the electrical power supply means, e.g. battery
• CPC Class Codes: F02N 2200/063 Battery voltage
• CPC Class Codes: F02N 2200/0801 Vehicle speed
• CPC Class Codes: F02N 2200/102 Brake pedal position
• CPC Class Codes: Y02T 10/40 Engine management systems
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors

Abstract

A vehicle includes electric brakes, an engine with a starter, a battery and a controller. The battery has a voltage and is configured to power the starter, the electric brakes, and the controller. The controller is configured to, in response to a speed of the vehicle falling within a specified range without propulsive demand and while the voltage is greater than an upper voltage that varies based on a charge needed to engage the brakes to stop the vehicle, stop the engine.

Claims

1. A method of controlling an engine of a vehicle comprising:

stopping the engine by a controller in response to

a speed of the vehicle falling within a specified range in an absence of propulsive demand, and

a starter battery voltage being greater than a threshold that varies according to the speed.

2. The method of claim 1, wherein the threshold increases as the speed increases.

3. The method of claim 1, wherein the threshold further varies according to an angle of inclination of the vehicle.

4. The method of claim 1, wherein the threshold further varies according to a predicted weight of the vehicle.

5. The method of claim 1, wherein the threshold is indicative of a state of charge of a starter battery.

6. The method of claim 5, wherein the threshold further varies according to a predicted route and a predicted stopping point along the route such that the state of charge of the starter battery is greater than a predicted consumption of vehicle electrical components along the route to the predicted stopping point.

7. The method of claim 1, wherein the specified range has an upper and lower speed point.

8. The method of claim 7, wherein the upper speed point is greater than 40 kilometers per hour and the lower speed point is 5 kilometer per hours.

9. The method of claim 1, wherein the absence of propulsive demand is defined by depression of a brake pedal.

10. The method of claim 1, wherein the absence of propulsive demand is defined by a lack of an external force applied to an accelerator pedal.

11. A vehicle comprising:

electric brakes;

an engine including a starter;

a battery having a voltage and being configured to power the starter and brakes; and

a controller programmed to, in response to a speed of the vehicle falling within a specified range without propulsive demand and while the voltage is greater than an upper voltage that varies based on a charge needed to engage the brakes to stop the vehicle, stop the engine.

12. The vehicle of claim 11, wherein the upper voltage increases as the speed increases.

13. The vehicle of claim 11, wherein the upper voltage increases as an angle of inclination decreases.

14. The vehicle of claim 11, wherein the upper voltage further varies based on a predicted weight of the vehicle.

15. A vehicle comprising:

an engine;

a battery having a voltage and configured to supply power to a starter of the engine; and

a controller programmed to, in response to a speed of the vehicle falling within a specified range in an absence of propulsive demand while the voltage is greater than an upper voltage profile that varies based on a charge needed to control the vehicle, stop the engine.

16. The vehicle of claim 15, wherein the charge needed to control the vehicle is defined by a charge needed to supply power to electric brakes.

17. The vehicle of claim 16, wherein the charge needed to control the vehicle is defined by a charge needed to supply power to an electric power steering system.

18. The vehicle of claim 17, wherein the upper voltage profile is further based on a predicted route and a predicted stopping point along the route such that a state of charge of the battery is greater than a predicted consumption of electric brakes and electric power steering along the route to the predicted stopping point.

19. The vehicle of claim 18, wherein the state of charge is greater than a predicted consumption of electric brakes, electric power steering, and an electric air conditioning system along the route to the predicted stopping point.