INTERNAL COMBUSTION ENGINE AND METHOD FOR CONTROLLING SUCH AN INTERNAL COMBUSTION ENGINE

• US 20200132003A1
• Filed: 03/16/2018
• Published: 04/30/2020
• Est. Priority Date: 03/16/2017
• Status: Active Grant

• Current Assignee: Freevalve Ab
• Original Assignee: Freevalve Ab
• Inventors: HOGLUND, Anders, CARLSON, Urban
• Granted Patent: US 11,215,131 B2
• Time in Patent Office: Days
• CPC Class Codes: F02B 37/001 using exhaust drives arranged in parallel
• CPC Class Codes: F02B 37/013 with exhaust-driven pumps arranged in series
• CPC Class Codes: F02B 37/02 Gas passages between engine outlet and pump drive, e.g. reservoirs
• CPC Class Codes: F02D 13/0203 Variable control of intake and exhaust valves
• CPC Class Codes: F02D 13/0257 Independent control of two or more intake or exhaust valves respectively, i.e. one of two intake valves remains closed or is opened partially while the other is fully opened
• CPC Class Codes: F02D 2200/1002 Output torque
• CPC Class Codes: F02D 2200/101 Engine speed
• 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 41/005 according to engine operating conditions
• CPC Class Codes: F02D 41/008 Controlling each cylinder individually
• CPC Class Codes: F02D 41/0082 per groups or banks F02D41/0087 takes precedence
• CPC Class Codes: F02D 41/1475 Regulating the air fuel ratio at a value other than stoichiometry
• CPC Class Codes: F02M 26/04 with a single turbocharger
• CPC Class Codes: F02M 26/07 Mixed pressure loops, i.e. wherein recirculated exhaust gas is either taken out upstream of the turbine and reintroduced upstream of the compressor, or is taken out downstream of the turbine and reintroduced downstream of the compressor
• CPC Class Codes: F02M 26/08 for engines having two or more intake charge compressors or exhaust gas turbines, e.g. a turbocharger combined with an additional compressor
• CPC Class Codes: F02M 26/14 in relation to the exhaust system
• CPC Class Codes: F02M 26/17 in relation to the intake system
• CPC Class Codes: F02M 26/43 in which exhaust from only one cylinder or only a group of cylinders is directed to the intake of the engine
• CPC Class Codes: F02M 35/10222 Exhaust gas recirculation [EGR]; Positive crankcase ventilation [PCV]; Additional air admission, lubricant or fuel vapour admission
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies
• CPC Class Codes: Y02T 10/40 : Engine management systems

Abstract

An internal combustion engine includes combustion chambers, each having a first intake port, and first and second exhaust ports. An intake manifold is connected to the first intake port of each combustion chamber, a main pressure booster upstream of the intake manifold. An exhaust discharge arrangement includes a main exhaust manifold connected to the first exhaust port of each combustion chamber, the exhaust discharge arrangement connected to the second exhaust port of a first subset combustion chambers, and an exhaust recirculation manifold connected to the second exhaust port of a second subset combustion chambers and connected to an upstream side of the main pressure booster. The engine operates in high load and low load modes, which vary how the engine evacuates the exhaust gas of the second subset combustion chambers to the exhaust recirculation manifold. A related method is also disclosed.

Claims

1. An internal combustion engine (1) comprising a set of combustion chambers (2), each combustion chamber (2) being provided with:

a first controllable intake valve (4) configured for opening and closing a first intake port (5),

a first controllable exhaust valve (6) configured for opening and closing a first exhaust port (7), and

a second controllable exhaust valve (8) configured for opening and closing a second exhaust port (9), the internal combustion engine (1) further comprising;

an intake manifold (14) connected to the first intake port (5) of each combustion chamber of said set of combustion chambers (2),

a main pressure booster (15) arranged upstream said intake manifold (14) for providing gas to the intake manifold (14),

an exhaust discharge arrangement comprising a main exhaust manifold (17) connected to the first exhaust port (7) of each combustion chamber of said set of combustion chambers (2), the exhaust discharge arrangement being connected to the second exhaust port (9) of each combustion chamber of a first subset combustion chambers, and

an exhaust recirculation manifold (19) connected to the second exhaust port (9) of each combustion chamber of a second subset combustion chambers and connected to an upstream side of the main pressure booster (15) in relation to said intake manifold (14),

wherein the internal combustion engine (1) is configured to be driven in at least a high load mode (HL) and in a low load mode (LL), respectively, wherein

i) during the low load mode (LL), the internal combustion engine (1) is configured to evacuate at least 90% of the exhaust gas of the second subset combustion chambers to the exhaust recirculation manifold (19) and configured to evacuate the exhaust gas of the first subset combustion chambers to the exhaust discharge arrangement, and

ii) during the high load mode (HL), the internal combustion engine (1) is configured to evacuate at least 90% of the exhaust gas of the second subset combustion chambers to the exhaust discharge arrangement and configured to evacuate the exhaust gas of the first subset combustion chambers to the exhaust discharge arrangement,

wherein the maximum output torque [Nm] of the internal combustion engine (1) is dependent on engine speed [rpm], and during the high load mode (HL), the internal combustion engine (1) is configured to evacuate at least 1% of the exhaust gas of the second subset combustion chambers to the exhaust recirculation manifold (19) when the output torque is greater than 70% of said maximum output torque.

2. The internal combustion engine according to claim 1, wherein the maximum output torque [Nm] of the internal combustion engine (1) is dependent on engine speed [rpm], wherein the internal combustion engine (1) is configured to shift from low load mode (LL) to high load mode (HL) at a predetermined first torque level (T1) and configured to shift from high load mode (HL) to low load mode (LL) at a predetermined second torque level (T2).

3. The internal combustion engine according to claim 1, wherein the number of combustion chambers of the first subset combustion chambers is equal to or more than the number of combustion chambers of the second subset combustion chamber.

4. The internal combustion engine according to claim 1, wherein the exhaust discharge arrangement comprises a supplementary exhaust manifold (23) connected to the second exhaust port (9) of each combustion chamber of the first subset combustion chambers.

5. The internal combustion engine according to claim 4, wherein the internal combustion engine comprises a supplementary pressure booster (34) connected to an upstream side of the main pressure booster (15) in relation to said intake manifold (14), and wherein the supplementary exhaust manifold (23) is connected to an upstream side of the supplementary pressure booster (34) in relation to the main pressure booster (15).

6. The internal combustion engine according to claim 5, wherein the supplementary pressure booster (34) is constituted by a turbocharger.

7. The internal combustion engine according to claim 1, wherein a super-charger (27) is arranged between the main pressure booster (15) and the intake manifold (14).

8. The internal combustion engine according to claim 1, wherein the main pressure booster (15) is constituted by a turbocharger.

18. A non-transitory computer-readable medium on which is stored a computer program comprising instructions that, when executed by a computer, causes the internal combustion engine according to claim 1 to perform a method comprising:

operating the internal combustion engine (1) alternately in at least a high load mode (HL) and in a low load mode (LL), respectively, wherein

i) during the low load mode (LL), the internal combustion engine (1) evacuates at least 90% of the exhaust gas of the second subset combustion chambers to the exhaust recirculation manifold (19) and evacuates the exhaust gas of the first subset combustion chambers to the exhaust discharge arrangement, and

ii) during the high load mode (HL), the internal combustion engine ( )evacuates at least 90% of the exhaust gas of the second subset combustion chambers to the exhaust discharge arrangement and evacuates the exhaust gas of the first subset combustion chambers to the exhaust discharge arrangement,

wherein the maximum output torque [Nm] of the internal combustion engine (1) is dependent on engine speed [rpm], and during the high load mode (HL), the internal combustion engine (1) evacuates at least 1% of the exhaust gas of the second subset combustion chambers to the exhaust recirculation manifold (19) when the output torque is greater than 70% of the maximum output torque.

19. The internal combustion engine according to claim 2, wherein the number of combustion chambers of the first subset combustion chambers is equal to or more than the number of combustion chambers of the second subset combustion chamber.

20. The internal combustion engine according to claim 2, wherein the exhaust discharge arrangement comprises a supplementary exhaust manifold (23) connected to the second exhaust port (9) of each combustion chamber of the first subset combustion chambers.

9. A method for controlling an internal combustion engine (1) comprising a set of combustion chambers (2), each combustion chamber (2) being provided with:

a first controllable intake valve (4) configured for opening and closing a first intake port (5),

a first controllable exhaust valve (6) configured for opening and closing a first exhaust port (7), and

a second controllable exhaust valve (8) configured for opening and closing a second exhaust port (9), the internal combustion engine (1) further comprising;

an intake manifold (14) connected to the first intake port (5) of each combustion chamber of said set of combustion chambers (2),

a main pressure booster (15) arranged upstream said intake manifold (14) for providing gas to the intake manifold (14),

an exhaust discharge arrangement comprising a main exhaust manifold (17) connected to the first exhaust port (7) of each combustion chamber of said set of combustion chambers (2), the exhaust discharge arrangement being connected to the second exhaust port (9) of each combustion chamber of a first subset combustion chambers, and

an exhaust recirculation manifold (19) connected to the second exhaust port (9) of each combustion chamber of a second subset combustion chambers and connected to an upstream side of the main pressure booster (15) in relation to said intake manifold (14),

the method comprising;

operating the internal combustion engine (1) alternately in at least a high load mode (HL) and in a low load mode (LL), respectively, wherein

i) during the low load mode (LL), the internal combustion engine (1) evacuates at least 90% of the exhaust gas of the second subset combustion chambers to the exhaust recirculation manifold (19) and evacuates the exhaust gas of the first subset combustion chambers to the exhaust discharge arrangement, and

ii) during the high load mode (HL), the internal combustion engine ( )evacuates at least 90% of the exhaust gas of the second subset combustion chambers to the exhaust discharge arrangement and evacuates the exhaust gas of the first subset combustion chambers to the exhaust discharge arrangement,

wherein the maximum output torque [Nm] of the internal combustion engine (1) is dependent on engine speed [rpm], and during the high load mode (HL), the internal combustion engine (1) evacuates at least 1% of the exhaust gas of the second subset combustion chambers to the exhaust recirculation manifold (19) when the output torque is greater than 70% of the maximum output torque.

10. The method according to claim 9, wherein the maximum output torque [Nm] of the internal combustion engine (1) is dependent on engine speed [rpm], wherein the internal combustion engine (1) shift from low load mode (LL) to high load mode (HL) at a predetermined first torque level (T1) and shift from high load mode (HL) to low load mode (LL) at a predetermined second torque level (T2).

11. The method according to claim 10, wherein the first torque level (T1) is greater than the second torque level (T2).

12. The method according to claim 10, wherein the first torque level (T1) is 50% of said maximum output torque.

13. The method according to claim 10, wherein the second torque level (T2) is 45% of the said maximum output torque.

14. The method according to claim 9, wherein the internal combustion engine (1) during the low load mode (LL) is controlled such that an average lambda value of the second subset combustion chambers is equal to or more than 0.6 and equal to or less than 0.9.

15. The method according to claim 9, wherein the internal combustion engine (1) during the high load mode (HL) is controlled such that an average lambda value of the second subset combustion chambers is equal to or more than 0.8 and equal to or less than 1.

16. The method according to claim 9, wherein the internal combustion engine (1) during the low load mode (LL) is controlled such that an average lambda value of the first subset combustion chambers is equal to or more than 0.95 and equal to or less than 1.05.

17. The method according to claim 9, wherein the internal combustion engine (1) during the high load mode (HL) is controlled such that an average lambda value of the first subset combustion chambers is equal to or more than 0.8 and equal to or less than 1.