System and method for controlling a firing sequence of an engine to reduce vibration when cylinders of the engine are deactivated

• US 9,726,139 B2
• Filed: 03/13/2013
• Issued: 08/08/2017
• Est. Priority Date: 09/10/2012
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Beikmann, Randall S.
• Primary Examiner(s): Nguyen, Hung Q
• Assistant Examiner(s): Picon-Feliciano, Ruben
• Application Number:
  US13/799,129
• Publication Number:
  US 20140069381A1
• Time in Patent Office: 1,609 Days
• Field of Search: 12340612, 12340647, 12340611, 12340645, 12340646, 12340651, 12340676, 1231921, 1231922, 123325, 123332, 123394, 123198 F, 123FOR 101, 123FOR 109, 123FOR 111, 123FOR 113, 123FOR 117, 123FOR 118, 123FOR 121, 123481, 123321, 123322, 701 331, 701 337, 701 338, 701 339, 701 341, 701 84, 701 90, 701111, 701110, 701105, 701104, 701103, 701102, 701101, 701 302, 701 311, 701 329, 701112
• CPC Class Codes: F02D 2200/1004 Estimation of the output torque
• CPC Class Codes: F02D 2250/28 Control for reducing torsional vibrations, e.g. at acceleration
• CPC Class Codes: F02D 41/0087 Selective cylinder activation, i.e. partial cylinder operation deceleration cut-off F02D41/123
• CPC Class Codes: F02P 5/15 Digital data processing
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A system according to the principles of the present disclosure includes a vibration prediction module and a firing sequence module. The vibration prediction module predicts a modal response of a vehicle based on a firing sequence of an engine when a cylinder of the engine is deactivated. The firing sequence module adjusts the firing sequence of the engine based on the predicted modal response of the vehicle.

Claims

1. A system comprising:

a vibration prediction module that predicts a modal response of a vehicle based on a firing sequence of an engine when a cylinder of the engine is deactivated, wherein the firing sequence indicates a firing order of the engine and indicates which cylinders of the engine are active; and

a firing sequence module that adjusts the firing sequence of the engine based on the predicted modal response of the vehicle.

2. The system of claim 1 wherein the vibration prediction module predicts the modal response based on torque pulses of firing cylinders and non-firing cylinders in the firing sequence.

3. The system of claim 2 wherein the vibration prediction module:

predicts the modal response for each torque pulse;

determines the timing of the modal response for each torque pulse; and

sums portions of the modal responses that overlap in time to yield the modal response of the firing sequence.

4. The system of claim 3 further comprising a torque pulse module that estimates the torque pulses based on a pressure within an intake manifold of the engine and engine speed.

5. The system of claim 2 wherein the vibration prediction module predicts the modal response of each torque pulse based on a predetermined relationship between crankshaft torque and modal response.

6. The system of claim 2 wherein, for each of the torque pulses, the vibration prediction module predicts the modal response for multiple vibration modes based on a modal characteristic of the vehicle.

7. The system of claim 6 wherein, for each of the vibration modes, the vibration prediction module predicts an amplitude of vibration in multiple directions based on the modal response and a multiplier.

8. The system of claim 7 wherein the vibration prediction module determines a total vibration in each direction by summing the corresponding vibration amplitudes of all of the vibration modes.

9. The system of claim 1 wherein:

the vibration prediction module predicts the modal response of the vehicle corresponding to multiple firing sequence options; and

the firing sequence module selects one of the firing sequence options based on the predicted modal response of the vehicle.

10. The system of claim 9 wherein the vibration prediction module:

determines a first modal response for a previous firing sequence;

predicts a second modal response for each of the firing sequence options;

determines a total modal response for each of the firing sequence options based on the first modal response and the corresponding second modal response; and

selects one of the firing sequence options based on the total modal response.

21. The system of claim 1 wherein:

the vibration prediction module predicts an amplitude of vibration for multiple vibration modes based on the firing sequence and a modal characteristic of the vehicle; and

each vibration mode is characterized by a modal frequency and a modal direction.

23. The system of claim 1 wherein the modal response includes an amplitude of a vibration mode and a phase of the vibration mode.

11. A method comprising:

predicting a modal response of a vehicle based on a firing sequence of an engine when a cylinder of the engine is deactivated, wherein the firing sequence indicates a firing order of the engine and indicates which cylinders of the engine are active; and

adjusting the firing sequence of the engine based on the predicted modal response of the vehicle.

12. The method of claim 11 further comprising predicting the modal response based on torque pulses of firing cylinders and non-firing cylinders in the firing sequence.

13. The method of claim 12 further comprising:

predicting the modal response for each torque pulse;

determining the timing of the modal response for each torque pulse; and

summing portions of the modal responses that overlap in time to yield the modal response of the firing sequence.

14. The method of claim 13 further comprising estimating the torque pulses based on a pressure within an intake manifold of the engine and engine speed.

15. The method of claim 12 further comprising predicting the modal response of each torque pulse based on a predetermined relationship between crankshaft torque and modal response.

16. The method of claim 12 further comprising, for each of the torque pulses, predicting the modal response for multiple vibration modes based on a modal characteristic of the vehicle.

17. The method of claim 16 further comprising, for each of the vibration modes, predicting an amplitude of vibration in multiple directions based on the modal response and a multiplier.

18. The method of claim 17 further comprising determining a total vibration in each direction by summing the corresponding vibration amplitudes of all of the vibration modes.

19. The method of claim 11 further comprising:

predicting the modal response of the vehicle corresponding to multiple firing sequence options; and

selecting one of the firing sequence options based on the predicted modal response of the vehicle.

20. The method of claim 19 further comprising:

determining a first modal response for a previous firing sequence;

predicting a second modal response for each of the firing sequence options;

determining a total modal response for each of the firing sequence options based on the first modal response and the corresponding second modal response; and

selecting one of the firing sequence options based on the total modal response.

22. The method of claim 11 further comprising predicting an amplitude of vibration for multiple vibration modes based on the firing sequence and a modal characteristic of the vehicle, wherein each vibration mode is characterized by a modal frequency and a modal direction.

24. The method of claim 11 wherein the modal response includes an amplitude of a vibration mode and a phase of the vibration mode.