Search

EP-4739896-A1 - A METHOD OF OPERATING AN INTERNAL COMBUSTION ENGINE, A CONTROL ARRANGEMENT, A COMPUTER PROGRAM, A COMPUTER-READABLE MEDIUM, AN INTERNAL COMBUSTION ENGINE AND A VEHICLE

EP4739896A1EP 4739896 A1EP4739896 A1EP 4739896A1EP-4739896-A1

Abstract

A method (100) of operating an internal combustion engine (1) is disclosed. The method (100) comprises: calculating (101) a value of the torque (Ls) generated by the engine (1) by combusting fuel at a predetermined operation stage (Os), monitoring (103) temperature (T) of exhaust, comparing (105) the monitored temperature (T) with a threshold value (Tp), comparing (107) the calculated value of the torque (Ls) with a threshold value (Lp). If the monitored temperature (T) exceeds the threshold value (Tp), and if the calculated value of the torque (Ls) is lower than the threshold value (Lp): connecting (109) the load assembly (5) to the rotatable part (7) and activating (111) the fuel managing arrangement (3) to adjust combustion of the fuel such that the combustion occurs earlier than combustion at the predetermined operation stage (Os). A control arrangement (9), a computer program, a computer-readable medium (200), an internal combustion engine (1) and a vehicle (10) are also disclosed.

Inventors

  • JOHANSSON, Linus
  • JENSEN, MATHIAS

Assignees

  • Scania CV AB

Dates

Publication Date
20260513
Application Date
20240619

Claims (18)

  1. 1. A method (100) of operating an internal combustion engine (1) comprising: - a fuel managing arrangement (3) configured to control combustion of a fuel in a combustion chamber of the internal combustion engine (1) and - a load assembly (5) arranged connectable to a rotatable part (7) of the internal combustion engine (1) to use a portion of torque generated by the internal combustion engine (1) during operation of the internal combustion engine (1), wherein the method (100) is performed by a control arrangement (9), and wherein the method (100) comprises: - calculating (101) a value of the torque (Ls) generated by the internal combustion engine (1) by combusting the fuel at a predetermined operation stage (Os) of the internal combustion engine (1) during operation of the internal combustion engine (1), - monitoring (103) temperature (T) of exhaust generated by the internal combustion engine (1), - comparing (105) the monitored temperature (T) of the exhaust with a threshold value (Tp) of the temperature of the exhaust, - comparing (107) the calculated value of the torque (Ls) generated by the internal combustion engine with a threshold value of the torque (Lp), and if the monitored temperature (T) of the exhaust exceeds the threshold value (Tp) of the temperature of the exhaust, and if the calculated value of the torque (Ls) generated by the internal combustion engine (1) is lower than the threshold value of the torque (Lp): - connecting (109) the load assembly (5) to said rotatable part (7) of the internal combustion engine (1), and - activating (111) the fuel managing arrangement (3) to adjust combustion of the fuel in the combustion chamber of the internal combustion engine (1) such that the combustion of the fuel occurs earlier than combustion at said predetermined operation stage (Os) of the internal combustion engine (1).
  2. 2. The method (100) according to claim 1, wherein the internal combustion engine (1) is a spark ignition engine and wherein the step of activating (111) the fuel managing arrangement (3) comprises: - adjusting ignition of the fuel such that the ignition of the fuel occurs earlier than ignition at said predetermined operation stage (Os) during operation of the internal combustion engine (1).
  3. 3. The method (100) according to claim 1, wherein the internal combustion engine (1) is a compression ignition engine and wherein the step of activating (111) the fuel managing arrangement (3) comprises: - adjusting injection of the fuel such that the injection of the fuel occurs earlier than injection at said predetermined operation stage (Os) during operation of the internal combustion engine (1).
  4. 4. The method (100) according to any one of the preceding claims, wherein the step of calculating (101) a value of the torque (Ls) generated by the internal combustion engine (1) by combusting the fuel at a predetermined operation stage (Os) of the internal combustion engine (1) during operation of the internal combustion engine (1) is based on information about an amount of fuel and air provided to the internal combustion engine (1) and combusted at the predetermined operation stage (Os) of the internal combustion engine (1).
  5. 5. The method (100) according to any one of the preceding claims, wherein the load assembly (5) is a fan of a cooling system configured for cooling of the internal combustion engine (1).
  6. 6. The method (100) according to claim 5, therein the fan is a viscous fan.
  7. 7. The method (100) according to any one of the preceding claims, wherein the rotatable part (7) is a crankshaft or a camshaft of the internal combustion engine (1) and wherein the step of connecting (109) the load assembly (5) to said rotatable part (7) comprises connecting the load assembly (5) to the crankshaft or to the camshaft of the internal combustion engine (1).
  8. 8. The method (100) according to any one of the preceding claims, wherein the load assembly (5) is arranged axially in relation to the rotatable part (7).
  9. 9. The method (100) according to one of the preceding claims, wherein said threshold value of the torque (Lp) is an idle torque of the internal combustion engine (1).
  10. 10. A control arrangement (9) for an internal combustion engine (1) comprising: - a fuel managing arrangement (3) configured to control combustion of a fuel in a combustion chamber of the internal combustion engine (1) and - a load assembly (5) arranged connectable to a rotatable part (7) of the internal combustion engine (1) to use a portion of torque generated by the internal combustion engine (1) during operation of the internal combustion engine (1), wherein the control arrangement (9) is configured to: - calculating (101) a value of the torque (Ls) generated by the internal combustion engine (1) by combusting the fuel at a predetermined operation stage (Os) of the internal combustion engine (1) during operation of the internal combustion engine (1), - monitoring (103) temperature (T) of exhaust generated by the internal combustion engine (1), - comparing (105) the monitored temperature (T) of the exhaust with a threshold value (Tp) of the temperature of the exhaust, - comparing (107) the calculated value of the torque (Ls) generated by the internal combustion engine with a threshold value of the torque (Lp), wherein if the monitored temperature (T) of the exhaust exceeds the threshold value (Tp) of the temperature of the exhaust and the calculated value of the torque (Ls) generated by the internal combustion engine (1) is lower than the threshold value of the torque (Lp) control arrangement (9) is configured to perform: - connecting (109) the load assembly (5) to said rotatable part (7) of the internal combustion engine (1) and - activating (111) the fuel managing arrangement (3) to adjust combustion of the fuel in the combustion chamber of the internal combustion engine (1) such that the combustion of the fuel occurs earlier than combustion at said predetermined operation stage (Os) of the internal combustion engine (1).
  11. 11 . A computer program comprising instructions to cause the control arrangement (9) according to claim 10 to execute the steps of the method (100) according to any one of the claims 1 - 9.
  12. 12. A computer-readable medium (200) having stored thereon the computer program of claim 11.
  13. 13. An internal combustion engine (1) comprising: - a fuel managing arrangement (3) configured to control combustion of a fuel in a combustion chamber of the internal combustion engine (1), - a load assembly (5) arranged connectable to a rotatable part (7) of the internal combustion engine (1) to use a portion of torque (L) generated by the internal combustion engine (1) during operation of the internal combustion engine (1) and - a control arrangement (9) according to claim 10, wherein the control arrangement (9) is configured to perform the method according to any one of claim 1 to 9.
  14. 14. The internal combustion engine (1) according to claim 13, wherein the load assembly (7) is a fan of a cooling system configured for cooling of the internal combustion engine (1).
  15. 15. The internal combustion engine (1) according to claim 14, therein the fan is a viscous fan.
  16. 16. The internal combustion engine (1) according to any one of claims 13 to 15, wherein the rotatable part (7) is a crankshaft or a camshaft of the internal combustion engine (1) and wherein the load assembly (5) is arranged connectable to the crankshaft or to the camshaft of the internal combustion engine (1).
  17. 17. The internal combustion engine (1) according to any one of claims 13 to 16, wherein the load assembly (5) is arranged axially in relation to the rotatable part (7).
  18. 18. A vehicle (10) comprising an internal combustion engine (1) according to any one of claims 13 to 17.

Description

A method of operating an internal combustion engine, a control arrangement, a computer program, a computer-readable medium, an internal combustion engine and a vehicle TECHNICAL FIELD The present disclosure relates to a method of operating an internal combustion engine. The present disclosure further relates to a control arrangement for an internal combustion engine, a computer program, a computer-readable medium, an internal combustion engine and a vehicle comprising an internal combustion engine. BACKGROUND Internal combustion engines, such as four-stroke internal combustion engines, comprise one or more cylinders and a piston arranged in each cylinder. The pistons are connected to a crankshaft of the engine and are arranged to reciprocate within the cylinders upon rotation of the crankshaft. The engine usually further comprises one or more inlet valves and outlet valves as well as one or more fuel supply arrangements. The one or more inlet valves and outlet valves are controlled by a respective valve control arrangement usually comprising one or more camshafts rotatably connected to the crankshaft of the engine, via a belt, chain, gears, or similar. A four-stroke internal combustion engine completes four separate strokes while turning a crankshaft. A stroke refers to the full travel of the piston along the cylinder, in either direction. The strokes are completed in the following order, inlet stroke, compression stroke, expansion stroke and exhaust stroke. During operation of a conventional four-stroke internal combustion engine, the inlet valve control arrangement controls inlet valves of a cylinder to an open state during the inlet stroke of a piston within the cylinder, to allow air, or a mixture of air and fuel, to enter the cylinder. During the compression stroke, all valves should be closed to allow compression of the air, or the mixture of the air and fuel, in the cylinder. If the engine is in a power producing state, fuel in the cylinder is ignited, usually towards the end of the compression stroke, for example by a spark plug or by compression heat in the cylinder. Compression ignition engines, such as diesel engines, and some spark ignition engines, such as Otto engines, use a fuel injector configured to supply fuel into a combustion chamber. Gasoline engines having a fuel injector for supplying fuel into a combustion chamber are usually referred to as gasoline direct injection engines. In diesel engines, the injected fuel is ignited by compression heat, or by a glow plug. In Otto engines, the injected fuel is ignited by a spark of a spark plug. The combustion of fuel within the cylinder significantly increases pressure and temperature in the cylinder. The combustion of the fuel usually continues into a significant portion of the subsequent expansion stroke. The increased pressure and temperature in the cylinder obtained by the combustion is partially converted into mechanical work supplied to the crankshaft during the expansion stroke. Continuous movement of the crankshaft generates torque that is mostly used for driving wheels of a vehicle which is a load on the crankshaft and thereby on the internal combustion engine. The expansion stroke is also usually referred to as the combustion stroke, since usually, most of the combustion takes place during the expansion stroke. In the subsequent exhaust stroke, the exhaust valve control arrangement controls exhaust valves of the cylinder to an open state to allow exhaust gases to be expelled out of the cylinder into an exhaust system of the combustion engine. At a low load on an internal combustion engine, for example at idling, the rotational speed of the combustion engine may increase if minimum torque generated by the engine at the low load is greater than torque losses or internal losses of the engine and a possible added low load on the engine. During such conditions, in order to reduce the generated torque, it is common procedure to delay the combustion of fuel in the cylinder. However, delay of the combustion of fuel may cause the exhaust temperature to increase. High exhaust temperature may cause wear or damage of parts of an exhaust system, such as a muffler, a catalysator or turbocharger, of a vehicle comprising an internal combustion engine. When the exhaust temperature increases to a high level the combustion timing needs to be advanced which results in that the engine speed increases even more. To prevent the engine speed to increase to a high level, fuel supply is cut off. This causes unstable engine speed conditions at a low load on the internal combustion engine. SUMMARY Historically, efforts have been made to develop methods for controlling the idle speed of an internal combustion engine by regulating the air flow through an idle speed control system of the engine. However, by applying their detailed knowledge in the area of internal combustion engines, the inventors have identified and realized new improvement areas of controlling