System and method for starting a vehicle

• US 7,610,892 B2
• Filed: 07/22/2005
• Issued: 11/03/2009
• Est. Priority Date: 07/23/2004
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Butcher, Jonathan, Gartner, Paul, Okubo, Shunsuke, Syed, Fazal, McGee, Ryan
• Primary Examiner(s): Cronin; Stephen K
• Assistant Examiner(s): Castro; Arnold
• Application Number:
  US11/161,098
• Publication Number:
  US 20060016412A1
• Time in Patent Office: 1,565 Days
• Field of Search: 123/179.3, 123/179.4
• US Class Current: 123/179.3
• CPC Class Codes: B60K 6/365 with the gears having orbital motion
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60L 15/20 for control of the vehicle or its driving motor to achieve a desired performance, e.g. speed, torque, programmed variation of speed
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2240/421 Speed
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/441 Speed
• CPC Class Codes: B60L 2240/443 Torque
• CPC Class Codes: B60L 2240/445 Temperature
• CPC Class Codes: B60L 2240/486 Operating parameters
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 2250/26 by pedal actuation
• CPC Class Codes: B60L 2270/145 Structure borne vibrations
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• 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 2710/0644 Engine speed
• CPC Class Codes: B60W 30/192 : Mitigating problems related to power-up or power-down of the driveline, e.g. start-up of a cold engine
• CPC Class Codes: F02D 29/06 : peculiar to engines driving electric generators
• CPC Class Codes: F02D 31/001 : Electric control of rotation speed
• CPC Class Codes: F02D 41/061 : the corrections being time dependent
• CPC Class Codes: F02D 41/064 : at cold start F02D41/067 takes precedence
• CPC Class Codes: F02N 11/04 : the motors being associated with current generators
• CPC Class Codes: F02N 11/08 : Circuits or control means specially adapted for starting of engines
• CPC Class Codes: F02N 2200/023 : Engine temperature
• CPC Class Codes: F02N 2200/064 : Battery temperature
• CPC Class Codes: F02N 2300/102 : Control of the starter motor speed; Control of the engine speed during cranking
• CPC Class Codes: F02N 2300/2002 : using different starting modes, methods, or actuators depending on circumstances, e.g. engine temperature or component wear
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/64 : Electric machine technologies in electromobility
• 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
• CPC Class Codes: Y02T 10/72 : Electric energy management in electromobility

Abstract

The present invention provides a system and method for starting a vehicle in a cold temperature environment and minimizing the time spent by the vehicle within a resonance frequency zone during operation. The present invention includes a method of starting a vehicle engine comprising adjusting the speed of the engine during an engine start mode in accordance with a fixed value threshold. The method also includes determining whether the engine speed has reached the fixed value threshold or whether a time-based threshold has been reached. The method further includes transitioning out of the engine start mode into a normal operating mode when either the fixed value threshold or the time-based threshold has been reached.

Claims

1. A method of starting a vehicle engine, comprising:

adjusting a speed of the engine during an engine start mode in accordance with a fixed value threshold;

determining whether the engine speed has reached the fixed value threshold or whether a time-based threshold has been reached; and

upon a determination that the engine speed has not reached the fixed value threshold, transitioning out of the engine start mode into a normal operating mode when the time-based threshold has been reached;

wherein transitioning to the normal operating mode includes commanding a second target engine speed being greater than the fixed value threshold and adjusting the engine speed to achieve the second target engine speed.

2. A method according to claim 1, further including commanding a first target engine speed that is at least the same as the fixed value threshold.

3. A method according to claim 1, further comprising:

transitioning out of the engine start mode into a normal operating mode when the fixed value threshold has been reached prior to the time-based threshold.

4. A method according to claim 3, wherein adjusting the engine speed to achieve the second target engine speed includes accelerating the engine through a resonance frequency zone within a predetermined time period.

5. A method according to claim 4, wherein the predetermined time period is no more than 1.0 second.

6. A method according to claim 4, wherein the predetermined time period is about 0.3 seconds.

7. A method according to claim 1, wherein a generator is adapted to increase or decrease the engine speed.

8. A method according to claim 1, further comprising:

generating a generator mode command;

wherein the adjusting step comprises adjusting a speed of the engine during an engine start mode in accordance with a fixed value threshold and the generator mode command.

9. A method according to claim 1, wherein adjusting the engine speed of the engine during the engine start mode includes applying a torque to the engine through the use of a generator.

10. A method according to claim 9, wherein applying a torque to the engine through the use of a generator includes applying only a positive torque to the engine to increase the speed of the engine.

11. A method according to claim 1, wherein determining whether the engine speed has reached a fixed value threshold includes determining whether the engine speed is greater than an engine cranking speed and less than a resonance frequency speed.

12. A method of starting a vehicle having at least one engine in a cold environment, comprising:

configuring an engine start mode for the vehicle that includes achieving either a fixed value threshold or a time-based threshold; and

transitioning into a normal operating mode that includes accelerating the engine through a resonance frequency zone within a predetermined time period when the time-based threshold is reached despite the fixed value threshold not being reached, wherein the resonance frequency zone has a lower and an upper resonance frequency speed.

13. A method according to claim 12, wherein accelerating the engine through a resonance frequency zone within a predetermined time period includes a predetermined time period of no more than 1.0 second.

14. A method according to claim 12, wherein transitioning into a normal operating mode that includes accelerating the engine through a resonance frequency zone further includes:

commanding a second target engine speed, wherein the second target engine speed is greater than the upper resonance frequency speed; and

adjusting the engine speed to achieve the second target engine speed.

15. A method according to claim 12, further comprising transitioning into a normal operating mode that includes accelerating the engine through a resonance frequency zone when the fixed value threshold is reached prior to the time-based threshold.

16. A system for a vehicle, comprising:

an engine; and

a control system communicative with the engine and having at least one controller, the control system being configured to;

generate a first signal for adjusting the speed of the engine during a first operating mode in accordance with a fixed value threshold;

determine whether the engine speed has reached the fixed value threshold or whether a time-based threshold has been reached; and

upon a determination that the engine speed has not reached the fixed value threshold, transition to a second operating mode when the time-based threshold has been reached;

wherein, upon transitioning to the second operating mode, the control system is further configured to command a second target engine speed being greater than the fixed value threshold and generate a second signal for adjusting the engine speed to achieve the second target engine speed.

17. A system according to claim 16, further comprising:

a generator adapted to receive the first signal for adjusting the speed of the engine in accordance with the fixed value threshold and apply a torque to the engine to adjust the engine speed;

a battery coupled to the generator; and

a shaft having a damper attached thereto, the shaft being configured to couple the engine to the generator.

18. A system according to claim 16, wherein the control system is further configured to:

transition out of the first operating mode into the second operating mode when the fixed value threshold has been reached prior to the time-based threshold.

19. A system according to claim 16, wherein the control system being configured to generate the second signal for adjusting the engine speed is further configured to:

effect the adjusting of the engine speed by causing a acceleration of the engine through a resonance frequency zone within a predetermined time period.

20. A method of starting a vehicle engine comprising:

adjusting a speed of engine during an engine start mode in accordance with a fixed value threshold;

determining whether a time-based threshold has been reached; and

upon determining that the time-based threshold has been reached without the fixed value threshold being reached, transitioning out of the engine start mode into a normal operating mode that includes accelerating the engine through a resonance frequency zone within a predetermined time period.

21. The method of claim 20, further comprising:

otherwise, determining whether the engine speed has reached the fixed value threshold;

upon determining that the fixed value threshold has been reached, transitioning out of the engine staff mode into the normal operating mode.