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
Patent Information
- Application Number
- EP2024840180
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2023-07-07
- Filing Date
- 2024-06-19
- Publication Date
- 2026-05-13
AI Technical Summary
Internal combustion engines experience unstable engine speed and increased exhaust temperatures at low loads, leading to potential wear and damage to exhaust system components.
A method involving a fuel managing arrangement and a load assembly connected to the engine's rotatable part, which adjusts combustion timing and utilizes a portion of the engine's torque to manage exhaust temperature by connecting the load assembly when exhaust temperature exceeds a threshold and torque is below a certain value.
This approach stabilizes engine speed, reduces exhaust temperature, and improves engine efficiency by utilizing torque more effectively, thereby enhancing the durability of the exhaust system and optimizing fuel consumption.
Smart Images
Figure SE2024050601_16012025_PF_FP_ABST
Abstract
Description
[0001] 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
[0002] TECHNICAL FIELD
[0003] 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.
[0004] BACKGROUND
[0005] 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.
[0006] 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.
[0007] 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.
[0008] 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.
[0009] 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.
[0010] SUMMARY
[0011] 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 operation of an internal combustion engine at a low load, for reliable functioning of the engine and for reliable functioning of an exhaust system connected to the engine. It is an object of the present disclosure to overcome, or at least alleviate, at least some of the above-mentioned problems and drawbacks.
[0012] According to a first aspect of the present disclosure, the object is achieved by a method of operating an internal combustion engine comprising:
[0013] - a fuel managing arrangement configured to control combustion of a fuel in a combustion chamber of the internal combustion engine and
[0014] - a load assembly arranged connectable to a rotatable part of the internal combustion engine to use a portion of torque generated by the internal combustion engine during operation of the internal combustion engine.
[0015] The method comprises:
[0016] - calculating a value of the torque generated by the internal combustion engine by combusting the fuel at a predetermined operation stage of the internal combustion engine during operation of the internal combustion engine,
[0017] - monitoring temperature of exhaust generated by the internal combustion engine,
[0018] - comparing the monitored temperature of the exhaust with a threshold value of the temperature of the exhaust,
[0019] - comparing the calculated value of the torque generated by the internal combustion engine with a threshold value of the torque, and if the monitored temperature of the exhaust exceeds the threshold value of the temperature of the exhaust, and if the calculated value of the torque generated by the internal combustion engine is lower than the threshold value of the torque:
[0020] - connecting the load assembly to the rotatable part of the internal combustion engine, and
[0021] - activating the fuel managing arrangement to adjust combustion of the fuel in the combustion chamber of the internal combustion engine such that the combustion of the fuel occurs earlier than combustion at the predetermined operation stage of the internal combustion engine.
[0022] Since the method comprises controlling if the monitored temperature of the exhaust exceeds the threshold value of the exhaust temperature, and if the calculated value of the torque generated by the internal combustion engine is lower than the threshold value of the torque, it is known if the exhaust temperature is below or above the threshold value and if the calculated value of the torque generated by the internal combustion is above or below the threshold value of the torque. Moreover, since the method comprises the steps of: connecting the load assembly to the rotatable part of the internal combustion engine and activating the fuel managing arrangement to adjust combustion of the fuel in the combustion chamber such that the combustion of the fuel occurs earlier than combustion at the predetermined operation stage, which steps are performed during conditions that: the monitored temperature of the exhaust exceeds the threshold value of the temperature of the exhaust and the calculated value of the torque generated by the internal combustion engine is lower than the threshold value of the torque, a portion of the generated torque by the internal combustion engine is used by the load assembly connected to the rotatable part of the engine. Further, greater portion of the expansion stroke is used when combustion of the fuel occurs earlier than combustion at the predetermined operation stage, comparing to the portion of the expansion stroke when combustion occurs at the predetermined operation stage. The greater portion of the expansion stroke that is used results in an improved efficiency of the internal combustion engine because greater portion of energy generated during combustion of the fuel is transformed to work done by the pistons instead of heat. Consequently, greater portion of energy generated during combustion of the fuel is transformed to work done by the pistons of the engine and by the load assembly connected to the rotatable part instead of heat. As a result, an improved engine efficiency is achieved and the temperature of exhaust is decreased.
[0023] Accordingly, a method of operating an internal combustion engine is provided having conditions for efficient control of the exhaust temperature to prevent an undesirable increase of the exhaust temperature at low load on the internal combustion engine and at the same time having conditions for stable engine speed conditions at low load on the engine because fuel supply does not need to be stopped as it is done today. In addition, an undesirable increase of the exhaust temperature may be prevented in an efficient manner and thereby durability of an exhaust system connected to the engine may be improved. Further, an existing load assembly arranged at an internal combustion engine may be used which eliminates the need of auxiliary elements at the engine. Consequently, a method is provided having condition for reliable operation of an internal combustion engine at low load on the engine with stable engine speed, low exhaust temperature and with an efficient fuel consumption because the engine is driven with smallest possible amount of fuel provided to the engine.
[0024] Accordingly, a method is provided overcoming, or at least alleviating, at least some of the above-mentioned problems and drawbacks. As a result, the above-mentioned object is achieved. With the predetermined operation stage of the internal combustion engine is meant herein a certain position of pistons in cylinders of the internal combustion engine at predefined settings of the engine regarding i.a. the amount of air and fuel provided to the internal combustion engine. Particularly, the predetermined operation stage of the internal combustion engine corresponds to a position of the pistons at the moment of ignition of the compressed mixture of known amount of air and fuel for combustion of the fuel during operation of the internal combustion engine. At the moment of ignition, the pistons may be in compression stroke or in expansion stroke depending on the engine settings.
[0025] Combustion chambers may be formed between a piston top and cylinder walls of the cylinders of the internal combustion engine.
[0026] The load assembly may comprise a load body having a mass and an inertia during use. Since the load assembly is arranged connectable to the rotatable part of the internal combustion engine the load assembly may be connected to the rotatable part and may be disconnected from the rotatable part when desired. The load assembly is arranged to be driven by the rotatable part of the internal combustion engine when the load assembly is connected to the rotatable part. During operation of the internal combustion engine the rotatable part is rotating and is driven by the pistons arranged to transfer the movement of the pistons to the rotatable part. Pistons are driven to move in cylinders by energy generated when air and fuel mixture is combusted in the combustion chamber. Torque generated by an internal combustion engine is mostly used for driving wheels of a vehicle comprising the internal combustion engine. The load assembly connected to the rotatable part and driven by the rotatable part requires energy to be rotated and thereby uses a portion of torque generated by the internal combustion engine.
[0027] The method is performed by a control arrangement. The control arrangement may comprise a control unit and at least one sensor configured to measure data at the internal combustion engine, such as exhaust temperature, which data may be provided to the control unit and may be processed by the control unit to enable performing the method according to the present disclosure. The control unit may be connected to the fuel managing arrangement for receiving information from fuel managing arrangement regarding, i.a. the amount of air and fuel provided to the engine and for control of the fuel managing arrangement. The control unit may also be connected to the load assembly for control of the connection of the load assembly to the rotatable part. The conditions for the predetermined operation stage of the internal combustion engine may be saved in the control unit of the control arrangement before performing the method according to the present disclosure.
[0028] Thus, the value of torque generated by the internal combustion engine may be calculated based on the information about the engine settings at the predetermined operation stage of the internal combustion engine. The value of torque generated by the internal combustion engine may be calculated by the control unit of the control arrangement.
[0029] Optionally, the internal combustion engine is a spark ignition engine and the step of activating the fuel managing arrangement comprises:
[0030] - adjusting ignition of the fuel such that the ignition of the fuel occurs earlier than ignition at the predetermined operation stage during operation of the internal combustion engine.
[0031] Thus, the fuel managing arrangement may be configured to control a process of supply of the fuel to the internal combustion engine, such as injection of the fuel, and to control ignition timing in the combustion chamber, preferably be controlling a spark plug configured to generate a spark to ignite an air-fuel mixture in the combustion chamber.
[0032] Optionally, the internal combustion engine is a compression ignition engine and the step of activating the fuel managing arrangement comprises:
[0033] - adjusting injection of the fuel such that the injection of the fuel occurs earlier than injection at the predetermined operation stage during operation of the internal combustion engine.
[0034] Thus, the fuel managing arrangement may be configured to control injection timing of the fuel to be combusted in the combustion chamber such that the injection of the fuel occurs earlier than injection at the predetermined operation stage during operation of the internal combustion engine.
[0035] Optionally, the step of calculating a value of the torque generated by the internal combustion engine by combusting the fuel at a predetermined operation stage of the internal combustion engine during operation of the internal combustion engine is based on information about an amount of fuel and air provided to the internal combustion engine and combusted at the predetermined operation stage of the internal combustion engine. Thus, the torque may be calculated in a simple and reliable manner. Optionally, the load assembly is a fan of a cooling system configured for cooling of the internal combustion engine. As a result, a portion of torque generated by the internal combustion engine may be used for cooling of the engine when the fan is connected to rotatable part of the engine. In addition, an existing fan arranged at the engine may be used which eliminates the need of auxiliary elements at the engine. Consequently, efficiency of the engine may be yet improved.
[0036] Optionally, the fan is a viscous fan. A viscous fan is reliable in operation and provide efficient cooling of an internal combustion engine. Energy consumption of a viscous fan grows cubic with fan speed. Thus, a viscous fan may be an effective user of torque generated by an internal combustion engine which may be advantageable at low load on the engine.
[0037] Optionally, the rotatable part is a crankshaft or a camshaft of the internal combustion engine and the step of connecting the load assembly to the rotatable part comprises connecting the load assembly to the crankshaft or to the camshaft of the internal combustion engine. Thus, a portion of torque generated by the engine may be used by connecting the load assembly to the crankshaft or the camshaft of the engine.
[0038] Optionally, the load assembly is arranged axially in relation to the rotatable part. As a result, mounting of the load assembly at the engine may be facilitated as well as connecting of the load assembly to the rotatable part of the engine.
[0039] Optionally, the threshold value of the torque is an idle torque of the internal combustion engine.
[0040] According to a second aspect of the present disclosure, the object is achieved by control arrangement for an internal combustion engine comprising:
[0041] - a fuel managing arrangement configured to control combustion of a fuel in a combustion chamber of the internal combustion engine and
[0042] - a load assembly arranged connectable to a rotatable part of the internal combustion engine to use a portion of torque generated by the internal combustion engine during operation of the internal combustion engine, wherein the control arrangement is configured to:
[0043] - calculating a value of the torque generated by the internal combustion engine by combusting the fuel at a predetermined operation stage of the internal combustion engine during operation of the internal combustion engine,
[0044] - monitoring temperature of exhaust generated by the internal combustion engine, - comparing the monitored temperature of the exhaust with a threshold value of the temperature of the exhaust,
[0045] - comparing the calculated value of the torque generated by the internal combustion engine with a threshold value of the torque, wherein if the monitored temperature of the exhaust exceeds the threshold value of the temperature of the exhaust and the calculated value of the torque generated by the internal combustion engine is lower than the threshold value of the torque control arrangement is configured to perform:
[0046] - connecting the load assembly to said rotatable part of the internal combustion engine and
[0047] - activating the fuel managing arrangement to adjust combustion of the fuel in the combustion chamber of the internal combustion engine such that the combustion of the fuel occurs earlier than combustion at said predetermined operation stage of the internal combustion engine.
[0048] The control arrangement is arranged to perform the improved method of operating an internal combustion according to the present disclosure. The control arrangement may comprise a control unit and at least one sensor configured to measure data at the internal combustion engine, such as exhaust temperature, which data may be provided to the control unit and may be processed by the control unit to enable performing the method according to the present disclosure. The control unit may be connected to the fuel managing arrangement and to the load assembly for control of the fuel managing arrangement and for control of the connection of the load assembly to the rotatable part.
[0049] Since the control arrangement is arranged to perform the improved method of operating an internal combustion according to the present disclosure, the control arrangement has corresponding technical features and advantages as the corresponding features of the method described above. Consequently, these technical features and advantages are not repeated or explained anew in order to avoid unnecessary repetition.
[0050] Accordingly, a control arrangement is provided overcoming, or at least alleviating, at least some of the above-mentioned problems and drawbacks. As a result, the above-mentioned object is achieved.
[0051] According to a third aspect of the present disclosure, the object is achieved by a computer program comprising instructions to cause the control arrangement to execute the steps of the method according to any one of the embodiments described herein. Since the computer program comprises instructions to cause the control arrangement to execute the steps of the method according to any one of the embodiments described herein, a computer program is provided overcoming, or at least alleviating, at least some of the above-mentioned problems and drawbacks. As a result, the above-mentioned object is achieved.
[0052] According to a fourth aspect of the present disclosure, the object is achieved by a computer- readable medium having stored thereon the computer program comprising instructions to cause the control arrangement to execute the steps of the method according to any one of the embodiments described herein. Since the computer-readable medium has stored thereon the computer program comprising instructions to cause the control arrangement to execute the steps of the method according to any one of the embodiments described herein, a computer-readable medium is provided overcoming, or at least alleviating, at least some of the above-mentioned problems and drawbacks. As a result, the above-mentioned object is achieved.
[0053] According to a fifth aspect of the present disclosure, the object is achieved by an internal combustion engine comprising:
[0054] - a fuel managing arrangement configured to control combustion of a fuel in a combustion chamber of the internal combustion engine,
[0055] - a load assembly arranged connectable to a rotatable part of the internal combustion engine to use a portion of torque generated by the internal combustion engine during operation of the internal combustion engine and
[0056] - a control arrangement configured to perform the method according to any one of the embodiments described herein.
[0057] The internal combustion engine comprises a control arrangement arranged to perform the improved method of operating an internal combustion according to the present disclosure. The internal combustion engine and the control arrangement have corresponding technical features and advantages as the corresponding features of the method described above. Consequently, these technical features and advantages are not repeated or explained anew in order to avoid unnecessary repetition. Since the internal combustion engine comprises a control arrangement according to some embodiments, an internal combustion engine is provided overcoming, or at least alleviating, at least some of the above-mentioned problems and drawbacks. As a result, the above-mentioned object is achieved.
[0058] Optionally, the load assembly is a fan of a cooling system configured for cooling of the internal combustion engine. Optionally, the fan is a viscous fan.
[0059] Optionally, the rotatable part is a crankshaft or a camshaft of the internal combustion engine and wherein the load assembly is arranged connectable to the crankshaft or to the camshaft of the internal combustion engine.
[0060] Optionally, the load assembly is arranged axially in relation to the rotatable part.
[0061] According to a sixth aspect of the present disclosure, the object is achieved by a vehicle comprising an internal combustion engine according to any one of the embodiments described herein. Since the vehicle comprises an internal combustion engine according to some embodiments, a vehicle is provided overcoming, or at least alleviating, at least some of the above-mentioned problems and drawbacks. As a result, the above-mentioned object is achieved.
[0062] Further features of, and advantages with, the present invention will become apparent when studying the appended claims and the following detailed description.
[0063] BRIEF DESCRIPTION OF THE DRAWINGS
[0064] Various aspects of the invention, including its particular features and advantages, will be readily understood from the example embodiments discussed in the following detailed description and the accompanying drawings, in which:
[0065] Fig. 1 is a flow diagram illustrating a method according to the present disclosure, Fig. 2 illustrates a computer-readable medium according to some embodiments, Fig. 3 schematically illustrates a combustion engine according to some embodiments, Fig. 4 schematically illustrates a vehicle according to some embodiments,
[0066] Fig. 5 schematically illustrates a cylinder with a piston at a predetermined operation stage, Fig. 6 is a principle illustration of monitored temperature of exhaust in relation to a threshold value of the temperature of the exhaust and
[0067] Fig. 7 is a principle illustration of calculated value of torque generated by the internal combustion engine in relation to a threshold value of the torque.
[0068] DETAILED DESCRIPTION
[0069] Aspects of the present invention will now be described more fully. Like numbers refer to like elements throughout. Well-known functions or constructions will not necessarily be described in detail for brevity and / or clarity. Fig. 1 is a flow diagram illustrating a method 100 of operating an internal combustion engine 1. The internal combustion engine 1 is illustrated in details in Fig. 3. The internal combustion engine 1 comprises 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 Ls generated by the internal combustion engine 1 during operation of the internal combustion engine 1 , The method 100 is performed by a control arrangement 9 illustrated in Fig. 3.
[0070] The method 100 comprises:
[0071] - 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,
[0072] - monitoring 103 temperature T of exhaust generated by the internal combustion engine 1,
[0073] - comparing 105 the monitored temperature T of the exhaust with a threshold value Tp of the temperature of the exhaust,
[0074] - 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:
[0075] - connecting 109 the load assembly 5 to the rotatable part 7 of the internal combustion engine 1 , and
[0076] - 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 the predetermined operation stage Os of the internal combustion engine 1.
[0077] As a result, a method 100 of operating an internal combustion engine 1 is provided having conditions to improve the efficiency of the engine 1 and to decrease the temperature of exhaust if the exhaust temperature T exceeds the threshold value Tp at low load on the engine 1. Accordingly, a method 100 of operating an internal combustion engine 1 is provided having conditions for efficient control of the exhaust temperature to prevent an undesirable increase of the exhaust temperature at low load on the internal combustion engine 1 and at the same time having conditions for stable engine speed conditions at low load on the engine 1 because fuel supply does not need to be stopped as it is done today. In addition, an undesirable increase of the exhaust temperature may be prevented in an efficient manner and thereby durability of an exhaust system connected to the engine 1 may be improved. Further, an existing load assembly arranged at an internal combustion engine 1 may be used which eliminates the need of auxiliary elements at the engine 1. Consequently, a method is provided having condition for reliable operation of an internal combustion engine 1 at low load on the engine 1 with stable engine speed, low exhaust temperature and with an efficient fuel consumption because the engine 1 is driven with smallest possible amount of fuel provided to the engine 1.
[0078] After the steps of 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 in the combustion chamber such that the combustion of the fuel occurs earlier than combustion at the predetermined operation stage Os, it may be controlled if the exhaust temperature has decreased by applying the step of comparing 105 the monitored temperature T of the exhaust with the threshold value Tp. If the monitored temperature T of the exhaust is below the threshold value Tp of the temperature of the exhaust the method works well and the engine may be kept running at the adjusted combustion settings according to steps 109 and 111 and with the load assembly connected to the rotatable part 7.
[0079] If, after the steps 109 and 111 have been performed, the monitored temperature T of the exhaust still exceeds the threshold value Tp, then the fuel managing arrangement 3 may be activated 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 the latest adjusted operation stage of the internal combustion engine 1. The procedure may be repeated until the monitored temperature T of the exhaust is below the threshold value Tp.
[0080] The threshold value Tp of the temperature of the exhaust may be set to, for example, 810 °C.
[0081] The internal combustion engine 1 may be a spark ignition engine and the step of activating 111 the fuel managing arrangement 3 may comprise:
[0082] - 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.
[0083] The internal combustion engine 1 may be a compression ignition engine and the step of activating 111 the fuel managing arrangement 3 may comprise: - 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.
[0084] 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 preferably 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.
[0085] The threshold value of the torque Lp is preferably an idle torque of the internal combustion engine 1 . Value of the idle torque depends mostly on the size of the internal combustion engine.
[0086] Fig. 2 illustrates a computer-readable medium 200 according to some embodiments. The computer-readable medium 200 has stored thereon a computer program comprising instructions to cause the control arrangement 9 to execute the steps of the method 100 according to some embodiments.
[0087] One skilled in the art will appreciate that the method 100 of operating an internal combustion engine 1 may be implemented by programmed instructions. These programmed instructions are typically constituted by a computer program, which, when it is executed in the control arrangement 9, ensures that the control arrangement 9 carries out the desired control, such as the method steps 101, 103, 105, 107, 109 and 111 described herein. The computer program is usually part of the computer-readable medium 200 which comprises a suitable digital storage medium on which the computer program is stored.
[0088] The control arrangement 9 may comprise a control unit 11 illustrated in Fig. 3. The control unit 11 may comprise a calculation unit which may take the form of substantially any suitable type of processor circuit or microcomputer, e.g. a circuit for digital signal processing (digital signal processor, DSP), a Central Processing Unit (CPU), a processing unit, a processing circuit, a processor, an Application Specific Integrated Circuit (ASIC), a microprocessor, or other processing logic that may interpret and execute instructions. The herein utilised expression "calculation unit" may represent a processing circuitry comprising a plurality of processing circuits, such as, e.g., any, some or all of the ones mentioned above. The control unit 11 may further comprise a memory unit, wherein the calculation unit may be connected to the memory unit, which may provide the calculation unit with, for example, stored program code and / or stored data which the calculation unit may need to enable it to do calculations. The calculation unit may also be adapted to store partial or final results of calculations in the memory unit. The memory unit may comprise a physical device utilised to store data or programs, i.e., sequences of instructions, on a temporary or permanent basis. According to some embodiments, the memory unit may comprise integrated circuits comprising silicon-based transistors. The memory unit may comprise e.g. a memory card, a flash memory, a USB memory, a hard disc, or another similar volatile or non-volatile storage unit for storing data such as e.g. ROM (Read-Only Memory), PROM (Programmable Read- Only Memory), EPROM (Erasable PROM), EEPROM (Electrically Erasable PROM), etc. in different embodiments.
[0089] The control arrangement 9 is connected to components of the engine 1 and / or a vehicle 10 illustrated in Fig. 4, for receiving and / or sending input and output signals. These input and output signals may comprise waveforms, pulses or other attributes which the input signal receiving devices can detect as information and which can be converted to signals processable by the control arrangement 9 These signals may then be supplied to the calculation unit. One or more output signal sending devices may be arranged to convert calculation results from the calculation unit to output signals for conveying to other parts of the vehicle's control system and / or the component or components for which the signals are intended. Each of the connections to the respective components of the engine 1 and / or the vehicle 10 for receiving and sending input and output signals may take the form of one or more from among a cable, a data bus, e.g. a CAN (controller area network) bus, a MOST (media orientated systems transport) bus or some other bus configuration, or a wireless connection.
[0090] Control systems in modern vehicles generally comprise a communication bus system consisting of one or more communication buses for connecting a number of electronic control units (ECUs), or controllers, to various components on board the vehicle. Such a control system may comprise a large number of control units and taking care of a specific function may be shared between two or more of them. Vehicles of the type here concerned are therefore often provided with significantly more control arrangements than depicted in Fig. 3 and Fig. 4, as one skilled in the art will surely appreciate.
[0091] The computer-readable medium 200 may be provided for instance in the form of a data carrier carrying computer program code for performing the method steps 101, 103, 105, 107, 109 and 111 according to the present disclosure when being loaded into one or more calculation units of the control unit of the control arrangement 9. The data carrier may be, e.g. a CD ROM disc, as is illustrated in Fig. 2, or a ROM (read-only memory), a PROM (programable read-only memory), an EPROM (erasable PROM), a flash memory, an EEPROM (electrically erasable PROM), a hard disc, a memory stick, an optical storage device, a magnetic storage device or any other appropriate medium such as a disk or tape that may hold machine readable data in a non-transitory manner. The computer-readable medium 200 may furthermore be provided as computer program code on a server and may be downloaded to the control arrangement 9 remotely, e.g., over an Internet or an intranet connection, or via other wired or wireless communication systems.
[0092] Fig. 3 schematically illustrates an internal combustion engine 1, according to some embodiments, of the vehicle 10.
[0093] The internal combustion engine 1 is in some places herein referred to as the “engine 1” for the reason of brevity and clarity. As indicated above, the engine 1 is configured to provide motive power to a vehicle comprising the engine 1. However, according to further embodiments, the engine 1 , as referred to herein, may be a stationary engine, such as an engine configured to power a generator for producing electricity. The internal combustion engine 1 comprises a number of pistons 2, each configured to reciprocate in respective cylinder 13 of the internal combustion engine 1. A piston 2 is illustrated in Fig. 5. According to the illustrated embodiments, the engine 1 comprises six cylinders 13 and six pistons 2. According to further embodiments, the engine 1 may comprise another number of cylinders 13 and pistons 2.
[0094] According to the illustrated embodiments, the internal combustion engine 1 comprises a fuel injector arranged in each cylinder 13. The fuel injectors are configured to inject fuel directly into a cylinder 13 of the internal combustion engine 1. Therefore, the internal combustion engine 1 as referred to herein, may also be referred to as a “direct injection engine”. Moreover, according to the illustrated embodiments, the internal combustion engine 1 is a four-stroke engine. Therefore, the internal combustion engine 1 as referred to herein, may also be referred to as a “four-stroke internal combustion engine”, “a direct injected four-stroke internal combustion engine”, or the like.
[0095] The internal combustion engine 1 comprises a fuel managing arrangement 3 configured to control combustion of a fuel in a combustion chamber of the internal combustion engine 1. Thus, the fuel managing arrangement is configured to control the process of supply the fuel to the engine including i.a. the amount the supplied fuel and timing for combustion of the fuel. Further, the fuel managing arrangement 3 is configured to control other settings and parameters regarding combustion of the supplied fuel such as air to be mixed with the supplied fuel.
[0096] According to the illustrated embodiments, the fuel managing arrangement 3 is connected to the fuel injectors of each cylinder 13 to control the injection of fuel into the cylinders 13.
[0097] Further, the internal combustion engine 1 comprises 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. Yet further, the internal combustion engine 1 comprises a control arrangement 9 configured to:
[0098] - calculating 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
[0099] I during operation of the internal combustion engine 1,
[0100] - monitoring temperature T of exhaust generated by the internal combustion engine 1 ,
[0101] - comparing the monitored temperature T of the exhaust with a threshold value Tp of the temperature of the exhaust,
[0102] - comparing 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:
[0103] - connecting the load assembly 5 to said rotatable part 7 of the internal combustion engine 1 and
[0104] - activating 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.
[0105] According to the illustrated embodiments, the control arrangement 9 may comprise a control unit 11 and at least one sensor (not shown) configured to measure data at the internal combustion engine 1, such as exhaust temperature, which data is provided to the control unit
[0106] I I and is processed by the control unit 11 to enable performing the method according to the 1 present disclosure. Further, according to the illustrated embodiments, the control unit 11 is connected to the fuel managing arrangement 3 for receiving information from the fuel managing arrangement 3 regarding, i.a. the amount of air and fuel provided to the engine 1 and for control of the fuel managing arrangement 3. The control unit 11 is also connected to the load assembly 5 for control of the connection of the load assembly 5 to the rotatable part 7.
[0107] According to the embodiments illustrated in Fig. 3, the load assembly 5 comprises a connection device 5’ configured for controllable connection and disconnection of the load assembly 5 to and from the rotatable part 7. The connection device 5’ may be a hydraulic or electric connection device. Thus, the control unit 11 may be connected to the connection device 5’ to control the connection of the load assembly to the rotatable part 7.
[0108] According to the embodiments illustrated in Fig. 3, the rotatable part 7 is a crankshaft of the internal combustion engine 1. The crankshaft has a rotational axis a. The load assembly 5 is arranged axially in relation to the crankshaft. The crankshaft is illustrated in a schematic manner in Fig. 3.
[0109] According to some embodiments, the rotatable part 7 may be a camshaft of the internal combustion engine 1 and the load assembly 5 may by arranged connectable to the camshaft.
[0110] The load assembly 5 may be arranged at a distance measured radially from the rotatable part 7 and may be arranged connectable to the rotatable part via a belt or a chain.
[0111] Preferably, the load assembly 5 is a fan of a cooling system configured for cooling of the internal combustion engine 1. The fan may be a viscous fan. As an alternative, the load assembly 5 may be a generator or a compressor of an air conditioning system for a vehicle or other suitable element that may be driven by the rotatable part 7 of the engine 1 such as a clutch device.
[0112] Fig. 4 schematically illustrates a vehicle 10 according to some embodiments. According to the illustrated embodiments, the vehicle 10 is a truck, i.e., a type of heavy vehicle. According to further embodiments, the vehicle 10, as referred to herein, may be another type of heavy or lighter type of manned or unmanned vehicle for land or water-based propulsion such as a lorry, a bus, a construction vehicle, a tractor, a car, a ship, a boat, or the like. The vehicle 10 comprises a combustion engine 1 illustrated in Fig. 3 according to some embodiments.
[0113] Fig. 5 schematically illustrates a cylinder 13 with a piston 2 at a predetermined operation stage Os of the engine according to the present disclosure. With the operation stage of the internal combustion engine 1 is meant herein a certain position of the piston 2 in cylinder 13 of the internal combustion engine 1 at predefined settings of the engine 1 regarding i.a. the amount of air and fuel provided to the internal combustion engine 1. Particularly, the operation stage of the internal combustion engine 1 corresponds to a position of the piston 2 at the moment of ignition of the compressed mixture of known amount of air and fuel for combustion of the fuel during operation of the internal combustion engine 1. At the moment of ignition, the piston 2 may be in compression stroke or in expansion stroke depending on the engine settings.
[0114] As illustrated in Fig. 5, at the predetermined operation stage Os of the engine 1 , the piston 2 and particularly a top surface 4 of the piston 2 is positioned at a predetermined distance ds from a top inner wall surface 6 of the cylinder 13. Thus, when performing the method according to the present disclosure and particularly when activating 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, the piston 2 will be at a greater distance from the surface 6 than the predetermined distance ds corresponding to the predetermined operation stage Os.
[0115] The conditions for the predetermined operation stage Os of the internal combustion engine 1 may be saved in the control unit 11 of the control arrangement 9 before performing the method according to the present disclosure.
[0116] Fig. 6 illustrates a progress of the monitored temperature T of exhaust in relation to a threshold value Tp of the temperature of the exhaust during time t in a principle manner according to some embodiment. As illustrated in Fig. 6 the monitored temperature T increases to a value that exceeds the threshold value Tp and decreases after performing the method according to the present disclosure.
[0117] The threshold value Tp of the temperature of the exhaust may be set to, for example, 810 °C. Fig. 7 illustrates a progress of the calculated value of torque Ls generated by the internal combustion engine 1 in relation to a threshold value of the torque Lp in a principle manner according to some embodiment. As illustrated in Fig. 7 the calculated value of the torque Ls decreases to a value that is lower than the threshold value of the torque Lp which triggers the steps of: connecting 109 the load assembly 5 to the rotatable part 7 and activating 111 the fuel managing arrangement 3 according to the method described herein in order to decrease the exhaust temperature T as it is illustrated in Fig. 6.
[0118] The threshold value of the torque Lp is preferably an idle torque of the internal combustion engine 1 . Value of the idle torque depends mostly on the size of the internal combustion engine 1.
Claims
CLAIMS1. 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. 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. 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. 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. 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. The method (100) according to claim 5, therein the fan is a viscous fan.
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. 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. 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. 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 . 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. A computer-readable medium (200) having stored thereon the computer program of claim 11.
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. 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. The internal combustion engine (1) according to claim 14, therein the fan is a viscous fan.
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. 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. A vehicle (10) comprising an internal combustion engine (1) according to any one of claims 13 to 17.