Engine cylinder cut-off mode
By monitoring multiple variables to control the cylinder cut-off mode, the problem of low fuel efficiency during light-load operation was solved, resulting in improved fuel efficiency and reduced emissions, as well as reduced engine vibration and noise.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- PERKINS ENGINES
- Filing Date
- 2021-03-09
- Publication Date
- 2026-05-29
Smart Images
Figure CN113389641B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present invention relates to a method of controlling a cylinder cut-off mode of an engine. Furthermore, to an engine comprising a plurality of cylinders and a controller capable of initiating a cylinder cut-off mode. Furthermore, to a controller for controlling a cylinder cut-off mode of an engine. BACKGROUND
[0002] Cylinder cut-off, also known as cylinder deactivation, is a known technique for improving fuel efficiency and reducing emissions, especially unburned hydrocarbons, of an internal combustion engine (ICE) during light load operation. Cylinder cut-off can be achieved by keeping the intake and exhaust valves closed for a particular cylinder or by disabling the fuel injectors of a particular cylinder. SUMMARY
[0003] Embodiments of the present invention provide a method of controlling a cylinder cut-off mode of an engine, comprising the steps of:
[0004] a) initiating a cylinder cut-off mode, in which one or more cylinders of the engine are deactivated;
[0005] b) monitoring one or more deactivation variables while the cylinder cut-off mode is initiated; the one or more deactivation variables comprising one or more of:
[0006] intake manifold air temperature;
[0007] engine load factor;
[0008] engine speed; and
[0009] engine coolant temperature;
[0010] and
[0011] c) deactivating the cylinder cut-off mode so as to re-activate any deactivated cylinders when at least one of the deactivation variables exceeds its threshold value.
[0012] Another embodiment of the present invention provides an engine comprising a plurality of cylinders and a controller capable of initiating a cylinder cut-off mode, in which one or more of the plurality of cylinders are deactivated;
[0013] the controller is configured to:
[0014] a) initiate a cylinder cut-off mode;
[0015] b) monitor one or more deactivation variables while the cylinder cut-off mode is initiated; the one or more deactivation variables comprising one or more of:
[0016] intake manifold air temperature;
[0017] engine load coefficient;
[0018] engine speed; and
[0019] engine coolant temperature;
[0020] and
[0021] c) deactivating the cylinder cut-off mode when at least one of the deactivation variables exceeds its threshold value so as to re-activate any deactivated cylinders.
[0022] Another embodiment of the present invention provides a controller for controlling a cylinder cut-off mode of an engine, the controller being configured to:
[0023] a) activate a cylinder cut-off mode;
[0024] b) monitor one or more deactivation variables while the cylinder cut-off mode is activated; the one or more deactivation variables comprising one or more of:
[0025] intake manifold air temperature;
[0026] engine load coefficient;
[0027] engine speed; and
[0028] engine coolant temperature;
[0029] and
[0030] c) deactivating the cylinder cut-off mode when at least one of the deactivation variables exceeds its threshold value so as to re-activate any deactivated cylinders. BRIEF DESCRIPTION OF DRAWINGS
[0031] One or more embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which:
[0032] Figure 1 is a schematic flow diagram of an embodiment of a cylinder cut-off protection method according to the present invention; and
[0033] Figure 2 is a schematic diagram of an engine and controller for illustrating the operation of the method. DETAILED DESCRIPTION
[0034] Unless otherwise defined, all technical and scientific terms used in this specification shall have the same meaning as commonly understood by one of ordinary skill in the art to which the claimed subject matter belongs. It should be understood that the foregoing general description and the following detailed description are merely exemplary and explanatory, and are not restrictive of any subject matter claimed.
[0035] The following description pertains to embodiments of the invention. The description of the embodiments does not imply inclusion of all possible embodiments of the invention claimed in the appended claims. Many modifications, alterations, and equivalents not expressly described in the following embodiments may fall within the scope of the appended claims. Features described as part of an embodiment may be combined with features of one or more other embodiments unless the context explicitly requires otherwise.
[0036] In this specification, the use of the singular includes the plural unless the context clearly requires otherwise. In this application, unless otherwise stated, the use of "and / or" means "and" as well as "or".
[0037] Figure 1 A schematic flowchart of an embodiment of the cylinder cut-off protection method according to the present invention is shown.
[0038] This method can be used to determine when to enable the engine's cylinder cutoff mode and / or when to suspend / abort the engine's cylinder cutoff mode and / or when to deactivate the engine's cylinder cutoff mode.
[0039] This method can be applied to an engine to control its functions. It can be applied during engine start-up and / or during engine idling and / or during low-load conditions.
[0040] The engine can be part of the machine or a separate engine. The machine can be mobile or stationary. The machine can be wheeled or tracked. The machine can be used in construction and / or mining. The machine can include, for example, tractors, bulldozers, pipelaying machines, automatic graders, wheeled excavators, excavators, backhoe loaders, tracked loaders, wheeled loaders, articulated dump trucks, rigid dump trucks, or rollovers. The machine can include a locomotive. The engine can be a variable-speed engine.
[0041] This engine can be part of a generator, also known as a generator set. The generator can be a stationary generator or a mobile generator. The generator can be a standby generator. The generator can be used to generate electricity or a combination of electricity and useful heat, as part of a combined thermoelectric (CHP) generator. The engine can be a constant-speed engine.
[0042] The engine may be or includes an internal combustion engine (ICE). The ICE may use diesel fuel as its primary fuel. The diesel fuel may be, for example, conventional diesel or biodiesel.
[0043] The engine may have multiple cylinders. The engine may have 2 or more cylinders, optionally 4 or more cylinders, optionally 6 or more cylinders, optionally 8 or more cylinders, optionally 12 or more cylinders, optionally 16 or more cylinders, optionally 24 or more cylinders.
[0044] This method can be executed, wholly or partially, through the operation of a controller. The controller may include hardware and / or software. The controller may include a control unit or a computer program running on dedicated or shared computing resources. The controller may include a single unit or may consist of multiple operatively connected subunits. The controller may reside on a single processing resource or may be distributed across spatially separated computing resources. The controller may include one or more programmable and / or non-programmable memory units or subunits. The controller may include data storage and processing units or subunits. The controller may include an engine electronic control module (ECM) or form part of an engine electronic control module (ECM) operatively connected to the engine.
[0045] Figure 2 A schematic diagram of an engine 40 and a controller 41 for illustrating the operation of the method is shown. The engine 40 may include a plurality of cylinders 42.
[0046] The controller 41 may use one or more variables associated with the operation of the engine 40 as part of the method. These variables may include one or more of the following: engine speed 43, engine coolant temperature 44, engine intake manifold temperature 45, and engine load factor 46.
[0047] Engine 40 and / or controller 41 may include one or more associated sensors for detecting, determining, calculating, or inferring the aforementioned variables. For example, one or more of the following may be provided: engine coolant temperature sensor, engine intake manifold temperature sensor, engine speed sensor, engine manifold absolute pressure sensor, throttle position sensor, and intake sensor.
[0048] In step 1, an engine start command is provided. This engine start command may include activation via a virtual or physical key, switch, button, or other enabler. In some embodiments, the engine start command is provided by key 50 for operating the ignition controller. The engine 40 can be started under the control of controller 41.
[0049] In step 2, the controller 41 can check whether the starting status of the cylinder cut-off mode is considered normal (OK). The starting status is considered normal when one or more of the following statements are true (TRUE).
[0050] • Enable cylinder cut-off mode in controller 41;
[0051] No fault condition was detected in the fuel injector associated with cylinder 42 of engine 40;
[0052] No fault conditions associated with engine speed 43 or the engine speed sensor were detected; and
[0053] • Engine speed 43 is not zero.
[0054] Optionally, the startup status may be considered normal only if all of the above statements are true.
[0055] The cylinder cut-off mode can be enabled only when the starting condition is considered normal.
[0056] If the startup status is considered normal, the method can proceed to step 3.
[0057] If the startup condition in step 2 is not considered normal, the method can proceed to step 10 via arrow 21. In step 10, the controller can specify the cylinder cut-off mode as OFF. The method can then proceed to step 11, in which the engine 40 can operate with the cylinder cut-off mode disabled (i.e., all cylinders 42 of the engine 40 are enabled) until the engine 40 is stopped by the operation of key 50 (or other enabler).
[0058] In step 3, assuming the startup condition is considered normal, the controller 41 can check whether the cylinder cut-off mode entry condition is satisfied (MET). The entry condition is considered MET when one or more of the following statements are true:
[0059] • Engine coolant temperature 44°C is below or equal to the engine coolant temperature threshold.
[0060] • Engine intake manifold temperature 45°C or lower than or equal to the engine intake manifold temperature threshold; and
[0061] • The engine load factor of 46 is lower than or equal to the engine load factor threshold.
[0062] Optionally, a state is considered to be MET only if all of the above statements are true.
[0063] Cylinder cut-off mode can only be entered when the condition is considered to be MET.
[0064] The engine coolant temperature threshold can be set from -60 to 150°C, optionally from -40 to 90°C.
[0065] The engine intake manifold temperature threshold can be set from -60 to 300°C, optionally from -40 to 60°C.
[0066] The engine load factor threshold can be set from 0 to 120%, optionally from 1 to 100%.
[0067] Optionally, one or more of the variables among engine speed 43, engine coolant temperature 44, engine intake manifold temperature 45, and engine load factor 46 may be associated with a de-jitter variable that serves to prevent the controller 41 from calling the corresponding variable too frequently or acting too rapidly on the corresponding variable exceeding its threshold. For example, the engine coolant temperature variable 44 may have a de-jitter variable set for a time period of 0 to 60 seconds. For example, the engine intake manifold temperature 45 may have a de-jitter variable set for a time period of 0 to 60 seconds. For example, the engine load factor 46 may have a de-jitter variable set for a time period of 0 to 10 seconds.
[0068] In step 3, if the entry condition is MET, the method can proceed to step 4.
[0069] In step 3, if the entry condition is not MET, the method can proceed to step 10 via arrow 22. In step 10, the controller can specify the cylinder cut-off mode as OFF. The method can then proceed to step 11, in which engine 40 can operate with the cylinder cut-off mode disabled until engine 40 is stopped by operation of key 50 (or other enabler).
[0070] In step 4, controller 41 can determine whether engine speed 43 is lower than or equal to an engine speed threshold. This engine speed threshold can be a speed between 0 and 2000 rpm. This engine speed threshold can be used to determine whether there is no engine speed or the engine speed is insufficient to require or permit the activation of a cylinder cutoff mode.
[0071] In step 4, if the engine speed 43 is below or equal to a threshold, the method can proceed to step 10 via arrow 23. In step 10, the controller can specify the cylinder cut-off mode as off. The method can then proceed to step 11, in which the engine 40 can operate with the cylinder cut-off mode disabled (i.e., all cylinders of the engine 40 are enabled) until the engine 40 is stopped by the operation of key 50 (or other enabler).
[0072] In step 4, controller 41 can determine whether engine 40 is starting (i.e., starting from the off state) or running. If engine 40 is starting, the method can proceed to step 5 via arrow 24. If engine 40 is running, the method can proceed to step 6 via arrow 25.
[0073] Controller 41 can determine whether engine 40 is starting or running by monitoring engine speed. This determining factor can be, for example, a specified engine speed (rpm) or a predetermined deviation from a desired engine speed (rpm). For example, if the desired operating speed of engine 40 (which may optionally be a fixed desired operating speed) is 3000 rpm, controller 41 can be configured to handle engine speeds below, for example, 2900 rpm when engine 40 is starting, and handle speeds above 2900 rpm when engine 40 is running. In another example, controller 41 can be configured to handle engine speeds within, for example, 100 rpm of the desired operating speed when engine 40 is running, and to handle all lower speeds within, for example, 100 rpm of the desired operating speed when starting. Controller 41 can be configured such that once engine 40 is determined to be running, engine 40 cannot be determined to be starting until engine 40 is shut down and restarted.
[0074] In step 5, the controller 41 can monitor the start-up function of the engine 40. For example, the start-up function may be encountered during the start-up of the engine 40.
[0075] In step 5, the controller 41 can check whether the starting condition of the cylinder cut-off mode is considered "abnormal". The starting condition is considered abnormal when one or more of the following statements are not true:
[0076] • Enable cylinder cut-off mode in controller 41;
[0077] No fault condition was detected in the fuel injector associated with cylinder 42 of engine 40;
[0078] No fault conditions associated with engine speed 43 or the engine speed sensor were detected.
[0079] • Engine speed 43 is not zero;
[0080] • The cylinder cut-off mode has been activated for a duration of 10 to 30 seconds.
[0081] Optionally, the startup condition can be considered abnormal only if any one of the above statements is false.
[0082] If the startup condition is deemed abnormal, the method can proceed to step 10. In step 10, the controller can specify the cylinder cut-off mode as off. The method can then proceed to step 11, in which the engine 40 can operate with the cylinder cut-off mode disabled (i.e., all cylinders 42 of the engine 40 are enabled) until the engine 40 is stopped by the operation of key 50 (or other enabler).
[0083] Alternatively or concurrently, if controller 41 no longer requests the cylinder cut-off mode, for example if engine 40 is in droop mode, the method may proceed to step 10 via arrow 26. The droop mode can be used as an engine load-speed coefficient characteristic, allowing engine 40 to receive a load as a function of engine speed. This can be used as an open-loop engine governor.
[0084] In step 5, if the startup condition is normal and the controller 41 still requests the cylinder cut-off mode, the cylinder cut-off mode can be enabled during startup and operation to the desired engine speed.
[0085] In step 5, if the engine coolant temperature 44 exceeds the aforementioned engine coolant temperature threshold during start-up, the method may proceed to step 7 via arrow 28. In step 7, the cylinder cut-off mode may be terminated (i.e., any deactivated cylinder 42 may be reactivated) until the engine coolant temperature 44 returns below the engine coolant temperature threshold. Optionally, a coolant temperature hysteresis variable may be provided. The coolant temperature hysteresis variable may be, for example, 20°C. Optionally, the method may return to step 5 via arrow 28 only when the engine coolant temperature 44 has returned to a temperature equal to 'engine coolant temperature threshold minus coolant temperature hysteresis variable premature'. For example, when:
[0086] Engine coolant temperature threshold = 90℃
[0087] Coolant temperature hysteresis variable = 20℃
[0088] When the engine coolant temperature 44 exceeds 90°C, the cylinder cut-off mode will be terminated, and once the engine coolant temperature 44 returns to below 70°C (90°C-20°C=70°C), the cylinder cut-off mode will be reactivated.
[0089] As described above, the engine coolant temperature 44 can have a de-scrambling variable set for a period of 0 to 60 seconds. Accordingly, the method may not need to move from step 5 to step 7 unless the engine coolant temperature 44 continuously exceeds the engine coolant temperature threshold for at least the time period set as the de-scrambling variable.
[0090] In step 5, once the start-up is complete, the method can proceed to step 6 via arrow 27. As described above, the point from step 5 to step 6 can be determined by controller 41 by monitoring engine speed. This determining factor can be, for example, a specified engine speed (rpm) or a predetermined deviation from the desired engine speed (rpm).
[0091] In step 6, the controller 41 can monitor the idling mode of the engine 40. For example, the idling mode may be encountered during operation after the engine 40 has started, and in particular, the idling mode may be encountered during the idling of the engine 40 or when the engine is under low load.
[0092] In step 6, if the engine load factor 46 exceeds the aforementioned engine load factor threshold during idling, the method can proceed to step 9 via arrow 33, where the controller 41 can monitor the load function of the engine 40. As described above, the engine load factor 46 can have a de-jitter variable set for a time period of 0 to 10 seconds. Accordingly, the method may not proceed from step 6 to step 9 unless the engine load factor 46 continuously exceeds the engine load factor threshold for at least the time period set as the de-jitter variable.
[0093] In step 6, if the engine coolant temperature 44 exceeds the aforementioned engine coolant temperature threshold during idling, the method may move to step 7 via arrow 29. Step 7 operates in the same manner as described above, except that if the engine coolant temperature 44 returns to below the engine coolant temperature threshold or the engine coolant temperature threshold plus a coolant temperature hysteresis variable, the method may return to step 6 via arrow 29. The move from step 6 to step 7 may include the de-jittering variable discussed above regarding the move from step 5 to step 7.
[0094] In step 6, if the engine speed 43 exceeds the desired engine speed (e.g., the desired engine idle speed) by a greater than an engine speed threshold during idling, the method can proceed to step 8 via arrow 30, where the controller 41 can suspend the cylinder cut-off mode (i.e., temporarily reactivate any deactivated cylinders 42). The engine speed threshold can be a fixed value in rpm, a percentage of the desired engine speed in rpm, etc. For example, the engine speed threshold can be set to a value from 1 to 300 rpm. In one example, the threshold is set to 30 rpm.
[0095] In step 8, once the engine speed 43 has returned to within the desired engine speed threshold, the method can return to step 6, optionally continuing the de-chirping time. The cylinder cutoff mode may not be paused upon returning to step 6. This de-chirping time can be, for example, from 0 to 10 seconds.
[0096] The controller 41 may be configured with a pause limit variable to limit the number of times the method can access step 8 before the cylinder cutoff mode is completely disabled, until the engine 40 stops and restarts. The pause limit variable may be, for example, 2, 3, 4, or 5.
[0097] For example, when:
[0098] Desired engine idle speed = 1200 rpm
[0099] Engine speed threshold = 200 rpm
[0100] Dejitter time = 5 seconds
[0101] Access Restriction = 2
[0102] The method can achieve the following effects:
[0103]
[0104] In step 9, the controller 41 can monitor the load function of the engine 40. For example, when the engine is under medium or high load conditions, a load function may be encountered during the operation of the engine 40.
[0105] In step 6 and / or step 9, the controller 41 may check whether the starting condition of the cylinder cut-off mode is considered abnormal. The starting condition is considered abnormal when one or more of the following statements are not true:
[0106] • Enable cylinder cut-off mode in controller 41;
[0107] No fault condition was detected in the fuel injector associated with cylinder 42 of engine 40;
[0108] No fault conditions associated with engine speed 43 or the engine speed sensor were detected.
[0109] • Engine speed 43 is not zero;
[0110] Optionally, the startup condition can be considered abnormal only if any one of the above statements is false.
[0111] If the starting condition is deemed abnormal, the method can proceed from step 6 and / or from step 9 to step 10 via the corresponding arrows 32 and 34. In step 10, the controller can specify the cylinder cut-off mode as off. The method can then proceed to step 11, in which the engine 40 can operate with the cylinder cut-off mode disabled (i.e., all cylinders 42 of the engine 40 are enabled) until the engine 40 is stopped by the operation of key 50 (or other enabler).
[0112] Alternatively or alternatively, if the controller 41 no longer requests the cylinder cut-off mode, for example if the engine 40 is in droop mode, the method may move to step 10 via the corresponding arrows 32 and 34.
[0113] Alternatively or alternatively, if the engine speed 43 exceeds the maximum engine speed threshold of the engine 40 (which may be, for example, 50 rpm above the engine's rated maximum speed and / or the engine load factor 46 exceeds the maximum engine load factor threshold of the engine 40), the method may move to step 10 via the corresponding arrows 32 and 34, which may be, for example, 25% higher than the engine's maximum rated load factor.
[0114] Alternatively or alternatively, if controller 41 detects that the cylinder's ability to burn fuel is impaired and / or if controller 41 detects that it has received a controller area network (CAN) bus message indicating an intention to apply load to engine 41, the method may proceed to step 10 via the corresponding arrows 32 and 34.
[0115] Industrial applicability
[0116] This invention can be applied to controlling the cylinder cut-off mode of an engine.
[0117] The engine can be or includes an internal combustion engine (ICE). The ICE can use diesel fuel as its primary fuel. In some examples, the engine can be a diesel generator set engine.
[0118] The invention offers particular benefits when the engine is operating under cold conditions—for example, when the ambient temperature around the engine is below 10°C. In such conditions, starting the engine without starting aids can be challenging, especially for ICE engines using diesel as their primary fuel. For instance, in cold conditions, multiple cylinders may not burn fuel until a load is applied to the engine or the engine coolant heats up. Poor, incomplete combustion can lead to adverse conditions such as increased vibration, noise, and white smoke emissions indicating unburned hydrocarbons.
[0119] According to the present invention, a method for controlling the cylinder cutoff mode of an engine is provided, which can help the engine operate, especially under cold conditions.
[0120] The method for controlling the cylinder cutoff mode of an engine according to the present invention may include the following steps:
[0121] a) Activate cylinder cut-off mode, in which one or more cylinders of the engine are deactivated;
[0122] b) When cylinder cutoff mode is enabled, monitor one or more deactivated variables; the one or more deactivated variables include one or more of the following:
[0123] Intake manifold air temperature;
[0124] Engine load factor;
[0125] Engine speed; and
[0126] Engine coolant temperature;
[0127] as well as
[0128] c) When at least one of the deactivated variables exceeds its threshold, the cylinder cut-off mode is deactivated in order to reactivate any deactivated cylinder.
[0129] In step b), this step may additionally or alternatively include monitoring one or more of the following:
[0130] The ability of a cylinder to burn fuel; and
[0131] Receive a CAN bus message indicating the intention to apply a load to the engine.
[0132] In step c), the cylinder cut-off mode can be disabled when any of these deactivated variables exceeds its threshold.
[0133] In step a), the cylinder cut-off mode can be enabled during engine start-up mode and / or engine idle mode.
[0134] In step b), the cylinder cut-off mode can be enabled during engine idling.
[0135] In step c), when the engine load factor and / or the intake manifold air temperature exceed their threshold values, the cylinder cut-off mode can be deactivated until the engine stops and restarts.
[0136] Disabling cylinder cutoff mode once the engine load factor threshold is exceeded can advantageously prevent the maximum cylinder pressure from being exceeded on the activated cylinder.
[0137] In step c), when the engine coolant temperature exceeds its threshold, the cylinder cut-off mode can be deactivated until the engine coolant temperature drops below its threshold, optionally until the engine coolant temperature drops below its threshold by a hysteresis.
[0138] In step c), when the engine speed exceeds its threshold, the cylinder cut-off mode can be deactivated until the engine speed drops below its threshold, optionally until the engine speed drops below its threshold for a predetermined period of time.
[0139] In step c), since the engine speed exceeds its threshold, the cylinder cut-off mode can withstand a predetermined maximum number of deactivation and reactivation cycles, and thereafter another instance of the engine speed exceeding its threshold causes the cylinder cut-off mode to be deactivated until the engine stops and restarts.
[0140] The engine of the present invention may include a plurality of cylinders and a controller that can be activated to enable a cylinder cut-off mode, wherein one or more of the plurality of cylinders are deactivated;
[0141] The controller can be configured as follows:
[0142] a) Activate cylinder cutoff mode;
[0143] b) Monitor one or more deactivated variables while the cylinder cutoff mode is enabled; the one or more deactivated variables include one or more of the following:
[0144] Intake manifold air temperature;
[0145] Engine load factor;
[0146] Engine speed; and
[0147] Engine coolant temperature;
[0148] as well as
[0149] c) When at least one of the deactivated variables exceeds its threshold, the cylinder cut-off mode is deactivated in order to reactivate any deactivated cylinder.
[0150] The controller may be additionally or alternatively configured to monitor one or more of the following:
[0151] The ability of a cylinder to burn fuel; and
[0152] Receive a CAN bus message indicating the intention to apply a load to the engine.
[0153] The controller of the present invention for controlling the cylinder cutoff mode of an engine can be configured as follows:
[0154] a) Activate cylinder cutoff mode;
[0155] b) Monitor one or more deactivated variables while the cylinder cutoff mode is enabled; the one or more deactivated variables include one or more of the following:
[0156] Intake manifold air temperature;
[0157] Engine load factor;
[0158] Engine speed; and
[0159] Engine coolant temperature;
[0160] as well as
[0161] c) When at least one of the deactivated variables exceeds its threshold, the cylinder cut-off mode is deactivated in order to reactivate any deactivated cylinder.
[0162] The controller may be additionally or alternatively configured to monitor one or more of the following:
[0163] The ability of a cylinder to burn fuel; and
[0164] Receive a CAN bus message indicating the intention to apply a load to the engine.
[0165] Advantageously, the present invention enables operation of a cylinder cutoff mode that reduces excessive vibration, noise, and white smoke emissions from the engine, while ensuring that the cylinder cutoff mode is deactivated when needed. In particular, the method allows control of the cylinder cutoff mode during engine idling.
[0166] It should be understood that at least some of the figures and descriptions in this invention have been simplified to focus on elements relevant to a clear understanding of the invention, while other elements that those skilled in the art would understand or might need have been omitted for clarity. Because these elements are well known to those skilled in the art, and because they do not necessarily contribute to a better understanding of the invention, a description of these elements is not provided herein.
Claims
1. A method for controlling a cylinder deactivation mode of an engine, comprising the following steps: a) Activate cylinder cut-off mode during the engine start-up mode and / or the engine idle mode, wherein one or more cylinders of the engine are deactivated. b) When cylinder cutoff mode is enabled, monitor one or more deactivated variables; the one or more deactivated variables include one or more of the following: Intake manifold air temperature; Engine speed; and Engine coolant temperature; as well as c) When at least one of the deactivated variables exceeds its threshold, the cylinder cut-off mode is deactivated to reactivate any deactivated cylinder, wherein when the engine speed exceeds its threshold, the cylinder cut-off mode is deactivated until the engine speed decreases below its threshold, the cylinder cut-off mode is able to withstand a predetermined maximum number of deactivation and reactivation cycles due to the engine speed exceeding its threshold, and thereafter another instance of the engine speed exceeding its threshold causes the cylinder cut-off mode to be deactivated until the engine stops and restarts.
2. The method of claim 1, wherein in step b), the step further includes monitoring one or more of the following: The ability of a cylinder to burn fuel; as well as Receive a CAN bus message indicating the intention to apply a load to the engine.
3. The method of claim 1, wherein in step b), the step further includes monitoring the engine load factor.
4. The method according to any one of claims 1-3, wherein in step b), the cylinder cut-off mode is enabled during the engine's idle mode.
5. The method according to any one of claims 1-3, wherein in step c), when the engine load factor and / or the intake manifold air temperature exceed their threshold values, the cylinder cut-off mode is deactivated until the engine stops and restarts.
6. The method according to any one of claims 1-3, wherein in step c), when the engine coolant temperature exceeds its threshold, the cylinder cut-off mode is deactivated until the engine coolant temperature drops below its threshold.
7. According to the method of claim 6, in step c), when the engine coolant temperature exceeds its threshold, the cylinder cut-off mode is deactivated until the engine coolant temperature drops below its threshold by a hysteresis.
8. The method according to claim 1, wherein in step c), when the engine speed exceeds its threshold, the cylinder cut-off mode is deactivated until the engine speed is reduced to below its threshold, and the engine speed is reduced to below its threshold for a predetermined period of time.
9. The method according to any one of claims 1-3, wherein the engine is a diesel engine.
10. The method according to claim 9, wherein the engine is a diesel generator set engine.
11. The method according to any one of claims 1-3, wherein the ambient temperature around the engine is less than 10°C.
12. An engine comprising a plurality of cylinders and a controller, the controller being capable of enabling a cylinder cut-off mode, wherein, One or more of the plurality of cylinders are deactivated; The controller is configured to: a) Activate cylinder cut-off mode during the engine's start-up mode and / or engine's idle mode; b) Monitor one or more deactivated variables while the cylinder cutoff mode is enabled; the one or more deactivated variables include one or more of the following: Intake manifold air temperature; Engine speed; and Engine coolant temperature; as well as c) When at least one of the deactivated variables exceeds its threshold, the cylinder cut-off mode is deactivated to reactivate any deactivated cylinder, wherein when the engine speed exceeds its threshold, the cylinder cut-off mode is deactivated until the engine speed decreases below its threshold, the cylinder cut-off mode is able to withstand a predetermined maximum number of deactivation and reactivation cycles due to the engine speed exceeding its threshold, and thereafter another instance of the engine speed exceeding its threshold causes the cylinder cut-off mode to be deactivated until the engine stops and restarts.
13. The engine of claim 12, wherein in step b), the controller is further configured to monitor one or more of the following: The ability of a cylinder to burn fuel; Engine load factor; as well as Receive a CAN bus message indicating the intention to apply a load to the engine.
14. The engine according to claim 13, wherein the engine is a diesel engine.
15. The engine according to claim 14, wherein the engine is a diesel generator set engine.
16. A controller for controlling cylinder cutoff modes of an engine, the controller being configured to: a) Activate cylinder cut-off mode during the engine's start-up mode and / or engine's idle mode; b) Monitor one or more deactivated variables while the cylinder cutoff mode is enabled; the one or more deactivated variables include one or more of the following: Intake manifold air temperature; Engine speed; and Engine coolant temperature; as well as c) When at least one of the deactivated variables exceeds its threshold, the cylinder cut-off mode is deactivated to reactivate any deactivated cylinder, wherein when the engine speed exceeds its threshold, the cylinder cut-off mode is deactivated until the engine speed decreases below its threshold, the cylinder cut-off mode is able to withstand a predetermined maximum number of deactivation and reactivation cycles due to the engine speed exceeding its threshold, and thereafter another instance of the engine speed exceeding its threshold causes the cylinder cut-off mode to be deactivated until the engine stops and restarts.
17. The controller of claim 16, wherein in step b), the controller is additionally or alternatively configured to monitor one or more of the following: The ability of a cylinder to burn fuel; Engine load factor; as well as Receive a CAN bus message indicating the intention to apply a load to the engine.