METHOD FOR CONTROLLING A FORCED INDUCTION ENGINE

• US 20170248087A1
• Filed: 09/14/2015
• Published: 08/31/2017
• Est. Priority Date: 09/12/2014
• Status: Active Grant

• Current Assignee: Bombardier Recreational Products Incorporated (Bombardier Incorporated)
• Original Assignee: Bombardier Recreational Products Incorporated (Bombardier Incorporated)
• Inventors: REISENBERGER, Christian, MORIN, Frederic
• Granted Patent: US 10,598,105 B2
• Time in Patent Office: Days
• CPC Class Codes: F02B 29/04 Cooling of air intake supply
• CPC Class Codes: F02D 11/105 characterised by the function converting demand to actuation, e.g. a map indicating relations between an accelerator pedal position and throttle valve opening or target engine torque
• 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 2200/0404 Throttle position
• CPC Class Codes: F02D 2200/0406 Intake manifold pressure
• 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 9/08 Throttle valves specially adapted therefor; Arrangements of such valves in conduits
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A method for controlling a forced induction engine includes: determining a first air pressure upstream of an air compressor, the air compressor supplying compressed air to the engine; determining a second air pressure downstream of the air compressor; determining a limit air flow rate to the engine corresponding to the surge limit of the air compressor based at least in part on the first and second air pressures; and controlling a throttle valve actuator to position the throttle valve at a position providing an air flow rate that is greater than or equal to the limit air flow rate. A vehicle power pack having a control unit implementing the method and a vehicle having the vehicle power pack are also disclosed.

Claims

1. A method for controlling a forced induction engine comprising:

determining a first air pressure upstream of an air compressor, the air compressor supplying compressed air to the engine;

determining a second air pressure downstream of the air compressor;

determining a limit air flow rate to the engine corresponding to a surge limit of the air compressor based at least in part on the first and second air pressures; and

controlling a throttle valve actuator to position a throttle valve at a position providing an air flow rate that is greater than or equal to the limit air flow rate.

2. The method of claim 1, further comprising:

determining an engine speed; and

determining a limit position of the throttle valve of the engine based at least in part on the engine speed and the limit air flow rate, the limit position of the throttle valve being a position of the throttle valve below which the surge limit of the air compressor is exceeded;

wherein controlling the throttle valve actuator to position the throttle valve at the position providing an air flow rate that is greater than or equal to the limit air flow rate includes controlling the throttle valve actuator to position the throttle valve at a position being greater than or equal to the limit position.

3. The method of claim 2, wherein the limit position is an idle position when a ratio of the second air pressure over the first air pressure is below a predetermined value.

4. The method of claim 1, wherein determining the first air pressure includes determining a third air pressure upstream of an air filter, the air filter being disposed upstream of the air compressor.

5. The method of claim 1, wherein determining the second air pressure includes sensing a third air pressure downstream of an air cooler, the air cooler being disposed downstream of the air compressor.

6. The method of claim 5, wherein the air cooler is disposed upstream of the throttle valve.

7. The method of claim 2, further comprising determining an atmospheric air pressure;

and

wherein the limit position of the throttle valve of the engine is based at least in part on the atmospheric air pressure.

8. The method of claim 1, wherein the limit air flow rate is based at least in part on a ratio of the second air pressure over the first air pressure.

9. The method of claim 2, further comprising:

determining a throttle operator position; and

determining a desired throttle valve position based at least in part on the throttle operator position;

wherein controlling the throttle valve actuator to position the throttle valve at the position being greater than or equal to the limit position comprises;

controlling the throttle valve actuator to position the throttle valve at the desired throttle valve position if the desired throttle valve position is greater than the limit position; and

controlling the throttle valve actuator to position the throttle valve to a position other than the desired throttle valve if the desired throttle valve position is less than the limit position, the position other than the desired throttle valve being greater than or equal to the limit position.

10. The method of claim 9, wherein:

controlling the throttle valve actuator to position the throttle valve at the desired throttle valve position if the desired throttle valve position is greater than the limit position includes controlling the throttle valve actuator to position the throttle valve at the desired throttle valve position if the desired throttle valve position is greater than a control position of the throttle valve, the control position of the throttle valve being greater than the limit position; and

controlling the throttle valve actuator to position the throttle valve to the position other than the desired throttle valve if the desired throttle valve position is less than the limit position includes controlling the throttle valve actuator to position the throttle valve to the control position if the desired throttle valve position is less than the control position.

11. The method of claim 9, further comprising retarding an ignition timing of the engine if the desired throttle valve position is less than the limit position.

12. The method of claim 9, further comprising stopping fuel injection if the desired throttle valve position is less than the limit position.

13-17. -17. (canceled)

18. A method for controlling a forced induction engine comprising:

determining a first air pressure upstream of an air compressor, the air compressor supplying compressed air to the engine;

determining a second air pressure downstream of the air compressor;

determining an engine speed;

determining a limit position of a throttle valve of the engine based at least in part on the engine speed, the first air pressure and the second air pressure, the limit position of the throttle valve being a position of the throttle valve below which a surge limit of the air compressor is exceeded; and

controlling a throttle valve actuator to position the throttle valve at a position being greater than or equal to the limit position.

19. The method of claim 18, further comprising determining a limit air flow rate to the engine corresponding to the surge limit of the air compressor based at least in part on the first and second air pressures;

and

wherein determining the limit position of the throttle valve of the engine is based at least in part on the limit air flow rate.

20. The method of claim 18, wherein the limit position is an idle position when a ratio of the second air pressure over the first air pressure is below a predetermined value.

21. The method of claim 18, wherein determining the first air pressure includes determining a third air pressure upstream of an air filter, the air filter being disposed upstream of the air compressor.

22. The method of claim 18, wherein determining the second air pressure includes sensing a third air pressure downstream of an air cooler, the air cooler being disposed downstream of the air compressor.

23. The method of claim 22, wherein the air cooler is disposed upstream of the throttle valve.

24. The method of claim 18, further comprising determining an atmospheric air pressure;

and

wherein the limit position of the throttle valve of the engine is based at least in part on the atmospheric air pressure.

25. The method of claim 19, wherein the limit air flow rate is based at least in part on a ratio of the second air pressure over the first air pressure.

26. The method of claim 18, further comprising:

determining a throttle operator position; and

determining a desired throttle valve position based at least in part on the throttle operator position;

wherein controlling the throttle valve actuator to position the throttle valve at the position being greater than or equal to the limit position comprises;

controlling the throttle valve actuator to position the throttle valve at the desired throttle valve position if the desired throttle valve position is greater than the limit position; and

controlling the throttle valve actuator to position the throttle valve to a position other than the desired throttle valve if the desired throttle valve position is less than the limit position, the position other than the desired throttle valve being greater than or equal to the limit position.

27. The method of claim 26, wherein:

controlling the throttle valve actuator to position the throttle valve at the desired throttle valve position if the desired throttle valve position is greater than the limit position includes controlling the throttle valve actuator to position the throttle valve at the desired throttle valve position if the desired throttle valve position is greater than a control position of the throttle valve, the control position of the throttle valve being greater than the limit position; and

controlling the throttle valve actuator to position the throttle valve to the position other than the desired throttle valve if the desired throttle valve position is less than the limit position includes controlling the throttle valve actuator to position the throttle valve to the control position if the desired throttle valve position is less than the control position.

28. The method of claim 26, further comprising retarding an ignition timing of the engine if the desired throttle valve position is less than the limit position.

29. The method of claim 26, further comprising stopping fuel injection if the desired throttle valve position is less than the limit position.

30-34. -34. (canceled)