Speed control method

• US 6,560,527 B1
• Filed: 10/18/1999
• Issued: 05/06/2003
• Est. Priority Date: 10/18/1999
• Status: Expired due to Term

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Russell, John David, Rutkowski, Brian D.
• Primary Examiner(s): Kwon, John
• Application Number:
  US09/420,322
• Time in Patent Office: 1,296 Days
• Field of Search: 701/110, 123/350, 123/352, 123/347, 123/348, 123/90.16
• US Class Current: 701/110
• CPC Class Codes: F01L 1/34 characterised by the provision of means for changing the timing of the valves without changing the duration of opening and without affecting the magnitude of the valve lift
• CPC Class Codes: F02B 2075/125 Direct injection in the combustion chamber for spark ignition engines, i.e. not in pre-combustion chamber
• CPC Class Codes: F02B 31/06 Movable means, e.g. butterfly valves
• CPC Class Codes: F02D 13/02 during engine operation
• CPC Class Codes: F02D 13/0207 changing valve lift or valve lift and timing
• CPC Class Codes: F02D 13/0211 the change of valve timing is caused by the change in valve lift, i.e. both valve lift and timing are functionally related
• CPC Class Codes: F02D 13/0215 changing the valve timing only
• CPC Class Codes: F02D 13/0219 by shifting the phase, i.e. the opening periods of the valves are constant
• CPC Class Codes: F02D 2013/0296 Changing the valve lift only
• CPC Class Codes: F02D 2041/001 for engines with variable valve actuation
• CPC Class Codes: F02D 2041/002 by simultaneous control of throttle and variable valve actuation
• CPC Class Codes: F02D 2041/389 for injecting directly into the cylinder
• CPC Class Codes: F02D 2200/0402 the parameter being determined by using a model of the engine intake or its components
• CPC Class Codes: F02D 2250/18 Control of the engine output torque
• CPC Class Codes: F02D 2250/21 during a transition between engine operation modes or states
• CPC Class Codes: F02D 23/00 Controlling engines characterised by their being supercharged
• CPC Class Codes: F02D 31/002 controlling air supply
• CPC Class Codes: F02D 31/003 for idle speed control
• CPC Class Codes: F02D 41/0002 Controlling intake air
• CPC Class Codes: F02D 41/0007 for control of turbo-charged or super-charged engines control of the pumps per se F02B37/12
• CPC Class Codes: F02D 41/3029 : further comprising a homogeneous charge spark-ignited mode
• CPC Class Codes: F02D 41/307 : to avoid torque shocks
• CPC Class Codes: Y02T 10/12 : Improving ICE efficiencies
• CPC Class Codes: Y02T 10/40 : Engine management systems

Abstract

A method for controlling an engine having both an electronically controlled inlet device, such as an electronic throttle unite, and an electronically controlled outlet device, such as a variable cam timing system is disclosed. The method of the present invention achieves cylinder air charge control that is faster than possible by using an inlet device alone. In other words, the method of the present invention controls cylinder air charge faster than manifold dynamics by coordination of the inlet and outlet device. This improved control is used to improve various engine control functions.

Claims

1. An article of manufacture comprising:

a computer storage medium having a computer program encoded therein for controlling an engine speed, the engine having at least one cylinder, the engine also having an intake manifold and an outlet control device for controlling flow from the intake manifold into the cylinder, said computer storage medium comprising;

code for generating a desired engine speed; and

code for adjusting the outlet control device to control the engine speed to said desired engine speed, wherein said outlet control device is at least one of a variable cam timing system or a variable valve lift mechanism.

2. The article recited in claim 1 wherein the engine further comprises an inlet control device for controlling flow into the intake manifold, the article further comprising code for adjusting both the inlet control device and the outlet control device to control the engine speed to said desired engine speed.

3. The article recited in claim 1 wherein said inlet control device is a throttle and the outlet control device is a variable cam timing system, the article further comprising:

code for adjusting the inlet control device and the outlet control device to affect flow in similar directions in response to an engine speed error; and

code for adjusting the inlet control device and the outlet control device to affect flow in opposite directions in response to an outlet control device setpoint error.

4. An article of manufacture comprising:

a computer storage medium having a computer program encoded therein for controlling an engine speed, the engine having at least one cylinder, the engine also having an intake manifold and an outlet control device for controlling flow from the intake manifold into the cylinder and an inlet control device to control flow into the intake manifold, said computer storage medium comprising;

code for generating a desired engine speed; and

code for adjusting the outlet control device to increase engine airflow when engine speed decreases below said desired engine speed and to decrease engine airflow when engine speed increases above said desired engine speed; and

code for adjusting the inlet control device based at least on an engine operating condition.

5. The article recited in claim 4 wherein the outlet control device is a variable cam timing system.

6. An article of manufacture comprising:

a computer storage medium having a computer program encoded therein for controlling an engine speed, the engine having at least one cylinder, the engine also having an intake manifold and an outlet control device for controlling flow from the intake manifold into the cylinder and an inlet control device to control flow into the intake manifold, said computer storage medium comprising;

code for determining whether the engine is in an idle condition;

code for generating a desired engine speed in response to said determination; and

code for adjusting the outlet control device to increase engine airflow when engine speed decreases below said desired engine speed; and

code for adjusting the inlet control device based at least on an engine operating condition.

7. The article recited in claim 6 wherein the outlet control device is a variable cam timing system.

8. An article of manufacture comprising:

a computer storage medium having a computer program encoded therein for controlling an engine speed, the engine having at least one cylinder, the engine also having an intake manifold and an outlet control device for controlling flow from the intake manifold into the cylinder and an inlet control device to control flow into the intake manifold, said computer storage medium comprising;

code for determining whether the engine is in an idle condition;

code for generating a desired engine speed in response to said determination; and

code for adjusting the outlet control device to control the engine speed to said desired engine speed and code for adjusting the inlet control device based at least on an engine operating condition; and

code for adjusting fuel injection based on an exhaust gas sensor to maintain a stoichiometric air-fuel ratio.

9. The article recited in claim 8 wherein the outlet control device is a variable cam timing system.

10. An article of manufacture comprising:

a computer storage medium having a computer program encoded therein for controlling an engine speed, the engine having at least one cylinder, the engine also having an intake manifold and an outlet control device for controlling flow from the intake manifold into the cylinder, wherein said outlet control device is at least one of a variable cam timing system or a variable valve lift mechanism, said computer storage medium comprising;

code for generating a desired engine speed when the engine is in an idle condition;

code for generating a desired outlet control device setpoint based on an operating condition during conditions other than said idle condition;

code for adjusting the outlet control device to control the engine speed to said desired engine speed when the engine is in said idle condition, and

code for adjusting the outlet control device to said control device setpoint during conditions other than said idle condition.

11. An article of manufacture comprising:

a computer storage medium having a computer program encoded therein for controlling an engine speed, the engine having at least one cylinder, the engine also having an intake manifold and an outlet control device for controlling flow from the intake manifold into the cylinder, the engine further comprises an inlet control device for controlling flow into the intake manifold, said computer storage medium comprising;

code for determining whether the engine is in an idle condition;

code for generating a desired engine speed in response to said determination; and

code for adjusting both the inlet control device and the outlet control device to control the engine speed to said desired engine speed.

12. An article of manufacture comprising:

a computer storage medium having a computer program encoded therein for controlling an engine speed, the engine having at least one cylinder, the engine also having an intake manifold and an outlet control device for controlling flow from the intake manifold into the cylinder, the engine further comprises an inlet control device for controlling flow into the intake manifold, said computer storage medium comprising;

code for generating a desired engine speed; and

code for adjusting both the inlet control device and the outlet control device to increase engine airflow when engine speed decreases below said desired engine speed and to decrease engine airflow when engine speed increases above said desired engine speed.

13. The article recited in claim 12 wherein the outlet control device is a variable cam timing system and the inlet control device is a throttle.

14. An article of manufacture comprising:

a computer storage medium having a computer program encoded therein for controlling an engine speed, the engine having at least one cylinder, the engine also having an intake manifold and a variable cam timing system for controlling flow from the intake manifold into the cylinder and a throttle for controlling flow into the intake manifold, said computer storage medium comprising;

code for generating a desired engine speed; and

code for adjusting the variable cam timing system and the throttle to affect flow in similar directions in response to an engine speed error; and

code for adjusting the variable cam timing system and the throttle to affect flow in opposite directions in response to an outlet control device setpoint error.

15. An article of manufacture comprising:

a computer storage medium having a computer program encoded therein for controlling an engine speed, the engine having at least one cylinder, the engine also having an intake manifold and an outlet control device for controlling flow from the intake manifold into the cylinder and an inlet control device for controlling flow into the intake manifold, said computer storage medium comprising;

code for generating a desired engine speed; and

code for adjusting the inlet control device and the outlet control device to affect flow in similar directions in response to an engine speed error; and

code for adjusting the inlet control device and the outlet control device to affect flow in opposite directions in response to an outlet control device setpoint error.

16. An article of manufacture comprising:

a computer storage medium having a computer program encoded therein for controlling an engine speed, the engine having at least one cylinder, the engine also having an intake manifold and an outlet control device for controlling flow from the intake manifold into the cylinder, wherein said outlet control device is at least one of a variable cam timing system or a variable valve lift mechanism, said computer storage medium comprising;

code for determining whether the engine is in an idle condition;

code for generating a desired engine speed in response to said determination; and

code for adjusting the outlet control device to increase engine airflow when engine speed decreases below said desired engine speed and to decrease engine airflow when engine speed increases above said desired engine speed.

17. An article of manufacture comprising:

a computer storage medium having a computer program encoded therein for controlling an engine speed, the engine having at least one cylinder, the engine also having an intake manifold and an outlet control device for controlling flow from the intake manifold into the cylinder, wherein said outlet control device is at least one of a variable cam timing system or a variable valve lift mechanism, said computer storage medium comprising;

code for generating a desired engine speed; and

code for adjusting the outlet control device based on a proportion of a difference between said desired engine speed and actual engine speed and an integral of a difference between said desired engine speed and actual engine speed.

18. An article of manufacture comprising:

a computer storage medium having a computer program encoded therein for controlling an engine speed, the engine having at least one cylinder, the engine also having an intake manifold and an outlet control device for controlling flow from the intake manifold into the cylinder, wherein said outlet control device is at least one of a variable cam timing system or a variable valve lift mechanism, said computer storage medium comprising;

code for generating a desired engine speed; and

code for adjusting the outlet control device to increase engine airflow when engine speed decreases below said desired engine speed.

19. An article of manufacture comprising:

a computer storage medium having a computer program encoded therein for controlling an engine speed, the engine having at least one cylinder, the engine also having an intake manifold and an outlet control device for controlling flow from the intake manifold into the cylinder, wherein said outlet control device is at least one of a variable cam timing system or a variable valve lift mechanism, said cylinder having a spark plug positioned therein, said computer storage medium comprising;

code for determining whether the engine is in an idle condition;

code for generating a desired engine speed in response to said determination; and

code for adjusting the outlet control device based on a proportion of a difference between said desired engine speed and actual engine speed and an integral of a difference between said desired engine speed and actual engine speed;

adjusting a spark advance to adjust ignition of said spark plug; and

code for adjusting a fuel injection amount based on an exhaust gas sensor to maintain air-fuel ratio at stoichiometry.

20. An article of manufacture comprising:

a computer storage medium having a computer program encoded therein for controlling an engine speed, the engine having at least one cylinder, the engine also having an intake manifold and an outlet control device for controlling flow from the intake manifold into the cylinder, wherein said outlet control device is at least one of a variable cam timing system or a variable valve lift mechanism, said computer storage medium comprising;

code for determining whether conditions are such that the outlet control device should be adjusted for speed control;

code for generating a desired speed in response to said determination; and

code for adjusting the outlet control device to increase engine airflow when speed decreases below said desired speed.

21. The article recited in claim 20 wherein said speed control is engine speed control.

22. An article of manufacture comprising:

a computer storage medium having a computer program encoded therein for controlling an engine speed, the engine having at least one cylinder, the engine also having an intake manifold and an outlet control device for controlling flow from the intake manifold into the cylinder, said computer storage medium comprising;

code for generating a desired engine speed;

code for calculating a desired air amount based on said desired speed; and

code for adjusting the outlet control device to control the engine speed to said desired engine speed.

23. The article recited in claim 22 wherein said outlet control device is at least one of a variable cam timing system or a variable valve lift mechanism.

24. The article recited in claim 22 wherein the engine also has an electronically controlled throttle valve.

25. The article recited in claim 24 further comprising code for adjusting said electronically controlled throttle valve based on manifold pressure.

26. The article recited in claim 22 wherein the engine also has catalytic converters for treating exhaust gas emissions.

27. The article recited in claim 22 further comprising code for feedback air/fuel control to maintain average air/fuel at stoichiometry based on an exhaust has oxygen sensor coupled to an engine exhaust.

28. The article recited in claim 22 wherein said air amount is at least one of cylinder air charge or an air flow.

29. An article of manufacture comprising:

a computer storage medium having a computer program encoded therein for controlling an engine speed, the engine having at least one cylinder, the engine also having an intake manifold and an outlet control device for controlling flow from the intake manifold into the cylinder, wherein said outlet control device is at least one of a variable cam timing system or a variable valve lift mechanism, the engine also having an electronically controlled throttle valve for controlling flow into the intake manifold, the engine further having an exhaust coupled to a catalytic converter, said computer storage medium comprising;

code for generating a desired engine speed;

code for calculating a desired air amount based on said desired speed;

code for adjusting the outlet control device to control the engine speed to said desired engine speed;

code for adjusting said electronically controlled throttle valve based on an engine operating parameter; and

code for adjusting a fuel injection amount to maintain average air/fuel at stoichiometry based on an exhaust gas oxygen sensor coupled to said engine exhaust.

30. The article recited in claim 29 wherein said air amount is at least one of cylinder air charge and an air flow.

31. The article recited in claim 29 wherein said engine operating parameter is manifold pressure.