Combination cylinder state and transmission gear control systems and methods

• US 9,599,047 B2
• Filed: 11/20/2014
• Issued: 03/21/2017
• Est. Priority Date: 11/20/2014
• 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., Wagh, Nitish J.
• Primary Examiner(s): YOUNG, EDWIN
• Application Number:
  US14/548,501
• Publication Number:
  US 20160146138A1
• Time in Patent Office: 852 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/10 including control of change-speed gearings
• CPC Class Codes: B60W 10/11 Stepped gearings
• CPC Class Codes: B60W 2710/1005 Transmission ratio engaged
• CPC Class Codes: B60W 30/1882 characterised by the working point of the engine, e.g. by using engine output chart
• CPC Class Codes: F02D 17/02 Cutting-out cutting-out engines in multiple engine arrangements F02D25/04
• CPC Class Codes: F02D 2200/0625 Fuel consumption, e.g. measured in fuel liters per 100 kms or miles per gallon
• CPC Class Codes: F02D 2200/101 Engine speed
• CPC Class Codes: F02D 41/0087 Selective cylinder activation, i.e. partial cylinder operation deceleration cut-off F02D41/123
• CPC Class Codes: F02D 41/0225 in relation with the gear ratio or shift lever position

Abstract

A firing module determines a target number of activated cylinders of an engine based on a torque request and a present gear ratio of a transmission. A combination identification module, based on the torque request, identifies a combination including a possible number of activated cylinders and a possible transmission gear ratio, wherein at least one of: the possible number of activated cylinders is different than the target number of activated cylinders; and the possible transmission gear ratio is different than the present gear ratio of the transmission. A transitioning module, when a second fuel consumption for the possible number of activated cylinders and the possible transmission gear ratio is less than a first fuel consumption for the target number of activated cylinders and the present gear ratio, selectively: transitions the target number of activated cylinders to the possible number of activated cylinders; and transitions a target gear ratio of the transmission to the possible transmission gear ratio. An activation/deactivation module controls cylinder activation and deactivation based on the target number of activated cylinders.

Claims

1. A control system of a vehicle, comprising:

a firing module that determines a target number of activated cylinders of an engine based on a torque request and a present gear ratio of a transmission;

a combination identification module that, based on the torque request, identifies a combination including a possible number of activated cylinders and a possible transmission gear ratio, wherein at least one of;

the possible number of activated cylinders is different than the target number of activated cylinders; and

the possible transmission gear ratio is different than the present gear ratio of the transmission;

a fueling estimation module that determines a first fuel consumption for the target number of activated cylinders and the present gear ratio and that determines a second fuel consumption for the possible number of activated cylinders and the possible transmission gear ratio;

a transitioning module that, when the second fuel consumption is less than the first fuel consumption, selectively;

transitions the target number of activated cylinders to the possible number of activated cylinders; and

transitions a target gear ratio of the transmission to the possible transmission gear ratio; and

an activation/deactivation module that controls cylinder activation and deactivation based on the target number of activated cylinders.

2. The system of claim 1 further comprising a transmission control module that controls the transmission based on the target gear ratio.

3. The system of claim 1 wherein the transitioning module selectively prevents the transitions when a difference between the present gear ratio and the possible transmission gear ratio is greater than a predetermined value.

4. The system of claim 1 wherein the combination identification module identifies the combination including the possible number of activated cylinders and the possible transmission gear ratio further based on a vehicle speed.

5. The system of claim 1 wherein the combination identification module identifies the combination including the possible number of activated cylinders and the possible transmission gear ratio further based on an engine speed.

6. The system of claim 1 wherein the fueling estimation module:

determines the first fuel consumption based on the target number of activated cylinders, the present gear ratio, and the torque request; and

determines the second fuel consumption based on the possible number of activated cylinders, the possible transmission gear ratio, and the torque request.

7. The system of claim 6 wherein the fueling estimation module determines the first and second fuel consumptions further based on a vehicle speed and an engine speed.

8. The system of claim 1 wherein the fueling estimation module determines the first and second fuel consumptions using a mapping that relates numbers of activated cylinders and gear ratios to fuel consumptions.

9. The system of claim 1 wherein:

the combination identification module, based on the torque request, further identifies a second combination including a second possible number of activated cylinders and a second possible transmission gear ratio;

at least one of;

the second possible number of activated cylinders is different than the target number of activated cylinders; and

the second possible transmission gear ratio is different than the present gear ratio of the transmission; and

at least one of;

the second possible number of activated cylinders is different than the possible number of activated cylinders; and

the second possible transmission gear ratio is different than the possible transmission gear ratio; and

the fueling estimation module further determines a third fuel consumption for the second possible number of activated cylinders and the second possible transmission gear ratio.

10. The system of claim 9 wherein, when the second fuel consumption is also less than the third fuel consumption, the transitioning module selectively:

transitions the target number of activated cylinders to the possible number of activated cylinders; and

transitions the target gear ratio of the transmission to the possible transmission gear ratio.

11. A control method for a vehicle, comprising:

determining a target number of activated cylinders of an engine based on a torque request and a present gear ratio of a transmission;

based on the torque request, identifying a combination including a possible number of activated cylinders and a possible transmission gear ratio, wherein at least one of;

the possible number of activated cylinders is different than the target number of activated cylinders; and

the possible transmission gear ratio is different than the present gear ratio of the transmission;

determining a first fuel consumption for the target number of activated cylinders and the present gear ratio;

determining a second fuel consumption for the possible number of activated cylinders and the possible transmission gear ratio;

when the second fuel consumption is less than the first fuel consumption, selectively;

transitioning the target number of activated cylinders to the possible number of activated cylinders; and

transitioning a target gear ratio of the transmission to the possible transmission gear ratio; and

controlling cylinder activation and deactivation based on the target number of activated cylinders.

12. The method of claim 11 further comprising controlling the transmission based on the target gear ratio.

13. The method of claim 11 further comprising selectively preventing the transitioning when a difference between the present gear ratio and the possible transmission gear ratio is greater than a predetermined value.

14. The method of claim 11 further comprising identifying the combination including the possible number of activated cylinders and the possible transmission gear ratio further based on a vehicle speed.

15. The method of claim 11 further comprising identifying the combination including the possible number of activated cylinders and the possible transmission gear ratio further based on an engine speed.

16. The method of claim 11 further comprising:

determining the first fuel consumption based on the target number of activated cylinders, the present gear ratio, and the torque request; and

determining the second fuel consumption based on the possible number of activated cylinders, the possible transmission gear ratio, and the torque request.

17. The method of claim 16 further comprising determining the first and second fuel consumptions further based on a vehicle speed and an engine speed.

18. The method of claim 11 further comprising determining the first and second fuel consumptions using a mapping that relates numbers of activated cylinders and gear ratios to fuel consumptions.

19. The method of claim 11 further comprising:

based on the torque request, identifying a second combination including a second possible number of activated cylinders and a second possible transmission gear ratio;

at least one of;

the second possible number of activated cylinders is different than the target number of activated cylinders; and

the second possible transmission gear ratio is different than the present gear ratio of the transmission; and

at least one of;

the second possible number of activated cylinders is different than the possible number of activated cylinders; and

the second possible transmission gear ratio is different than the possible transmission gear ratio; and

determining a third fuel consumption for the second possible number of activated cylinders and the second possible transmission gear ratio.

20. The method of claim 19 further comprising, when the second fuel consumption is also less than the third fuel consumption, selectively:

transitioning the target number of activated cylinders to the possible number of activated cylinders; and

transitioning the target gear ratio of the transmission to the possible transmission gear ratio.