METHOD FOR CONTROLLING EXHAUST GAS RE-CIRCULATION SYSTEM IN AN INTERNAL COMBUSTION ENGINE

• US 20140144414A1
• Filed: 11/27/2012
• Published: 05/29/2014
• Est. Priority Date: 11/27/2012
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Dean, Charles, Gonzalez Delgado, Manuel Angel, Lucido, Michael J.
• Granted Patent: US 9,032,941 B2
• Time in Patent Office: Days
• US Class Current: 123/568.14
• CPC Class Codes: F01L 1/185 Overhead end-pivot rocking arms
• CPC Class Codes: F01L 13/0036 the valves being driven by two or more cams with different shape, size or timing or a single cam profiled in axial and radial direction
• CPC Class Codes: F01L 2001/0476 Camshaft bearings
• CPC Class Codes: F01L 2001/0537 Double overhead camshafts [DOHC]
• CPC Class Codes: F01L 2305/00 Valve arrangements comprising rollers
• CPC Class Codes: F01L 2800/10 Providing exhaust gas recirculation [EGR]
• CPC Class Codes: F02B 47/08 the substances including exhaust gas
• CPC Class Codes: F02D 13/0246 changing valve lift or valve lift and timing
• CPC Class Codes: F02D 13/0273 Multiple actuations of a valve within an engine cycle
• CPC Class Codes: F02D 2041/0067 Determining the EGR temperature
• CPC Class Codes: F02D 2200/021 Engine temperature
• CPC Class Codes: F02D 41/006 using internal EGR control of valve overlap for internal EGR F02D13/0261; arrangements for internal EGR F02M26/01
• CPC Class Codes: F02D 41/0065 Specific aspects of external EGR control constructional details of EGR system F02M26/00
• CPC Class Codes: F02D 41/024 to increase temperature of the exhaust gas treating apparatus
• CPC Class Codes: F02D 41/064 at cold start F02D41/067 takes precedence
• CPC Class Codes: F02D 41/405 with post injections
• CPC Class Codes: F02M 26/01 Internal exhaust gas recirculation, i.e. wherein the residual exhaust gases are trapped in the cylinder or pushed back from the intake or the exhaust manifold into the combustion chamber without the use of additional passages
• CPC Class Codes: F02M 26/05 High pressure loops, i.e. wherein recirculated exhaust gas is taken out from the exhaust system upstream of the turbine and reintroduced into the intake system downstream of the compressor
• CPC Class Codes: F02M 26/06 Low pressure loops, i.e. wherein recirculated exhaust gas is taken out from the exhaust downstream of the turbocharger turbine and reintroduced into the intake system upstream of the compressor
• CPC Class Codes: F02M 26/15 in relation to engine exhaust purifying apparatus
• CPC Class Codes: F02M 26/25 : with coolers having bypasses
• CPC Class Codes: Y02T 10/12 : Improving ICE efficiencies
• CPC Class Codes: Y02T 10/40 : Engine management systems

Abstract

A method for controlling re-circulation of exhaust gas (EGR) in an internal combustion engine includes receiving a signal indicative of an engine operating temperature and comparing the engine operating temperature to a first predetermined IEGR threshold. When the engine operating temperature is less than the first predetermined internal EGR threshold, a first internal EGR mode is activated, whereby engine emissions may be reduced or combustion stability may be enhanced. When the engine operating temperature is greater than the first predetermined internal EGR threshold, the first internal EGR mode is deactivated, and a second internal EGR mode is activated, whereby emissions may be reduced as exhaust system heating is accelerated. When the operating temperature is greater than the second temperature threshold, the second internal EGR mode may be deactivated a third mode may be enabled with only external EGR.

Claims

1. A method for controlling re-circulation of exhaust gas in an internal combustion engine comprising:

receiving a signal indicative of an engine operating temperature;

comparing the engine operating temperature to a first predetermined IEGR threshold;

when the engine operating temperature is less than the first predetermined IEGR threshold, activating a first IEGR mode; and

when the engine operating temperature is greater than the first predetermined IEGR threshold, deactivating the first IEGR mode and activating a second IEGR mode.

2. The method of claim 1, further comprising comparing the engine operating temperature to a second predetermined IEGR threshold, and, when the engine operating temperature is greater than the second predetermined IEGR threshold deactivating the second IEGR mode.

3. The method of claim 2, further comprising activating an EEGR mode.

4. The method of claim 3, further comprising comparing the engine operating temperature to a predetermined EEGR threshold, wherein said activating an EEGR mode is performed when the engine operating temperature is greater than the predetermined EEGR threshold.

5. The method of claim 3, further comprising:

comparing the engine operating temperature to a predetermined EEGR threshold; and

deactivating the EEGR mode when the engine operating temperature is less than the predetermined EEGR threshold.

6. The method of claim 4, wherein the second predetermined IEGR threshold is equal to the predetermined EEGR threshold.

7. The method of claim 4, wherein the second predetermined IEGR threshold is greater than the predetermined EEGR threshold.

8. The method of claim 4, wherein the predetermined EEGR threshold is greater than the second predetermined IEGR threshold.

9. The method of claim 1, wherein the engine operating temperature is a coolant temperature.

10. The method of claim 1, wherein the engine operating temperature is an exhaust temperature.

11. The method of claim 1, wherein the engine operating temperature is an oil temperature.

12. The method of claim 1, wherein the first IEGR mode is configured for low HC.

13. The method of claim 1, wherein the first IEGR mode is configured for high combustion stability.

14. The method of claim 1, wherein the second IEGR mode is configured for low NOx.

15. The method of claim 1, wherein the second IEGR mode is configured for high exhaust temperature.

16. A method for controlling re-circulation of exhaust gas in an internal combustion engine comprising:

receiving a signal indicative of an engine operating temperature;

comparing the engine operating temperature to a first predetermined IEGR threshold;

when the engine operating temperature is less than the first predetermined IEGR threshold, activating a first IEGR mode; and

after a predetermined first period of time, deactivating the first IEGR mode and activating a second IEGR mode.

17. The method of claim 16, further comprising, after a predetermined second period of time, deactivating the second IEGR mode.

18. The method of claim 17, further comprising, after a predetermined third period of time, activating an EEGR mode.

19. The method of claim 18, wherein the predetermined third period of time is less than the predetermined second period of time.

20. The method of claim 18, wherein the predetermined third period of time is greater than the predetermined second period of time.