Engine control method, device, unit and storage medium

Abstract

The present application relates to an engine control method, device, unit and storage medium, and relates to the field of automotive technology. The method includes obtaining the current combustion stability value of the engine after the engine has been running at a target operating condition for a preset time. The current combustion stability value is used to characterize the combustion stability of the engine within the preset time. When the current combustion stability value is less than the combustion stability limit corresponding to the target operating condition, a first control strategy is executed; the first control strategy includes adjusting the current exhaust gas recirculation (EGR) rate to a first EGR rate, and, when the engine torque is controlled to be within a preset torque range, adjusting the current ignition advance angle to a first ignition advance angle; the first EGR rate is greater than the current EGR rate, and the first ignition advance angle is greater than the current ignition advance angle. In this way, the EGR rate of the engine under steady-state conditions can be increased, and fuel consumption can be reduced.

Description

Technical Field

[0001] The present application relates to the field of automobile technology, in particular to the field of engine technology, and specifically to an engine control method, device, unit and storage medium. Background Art

[0002] Exhaust gas recirculation (EGR) is a technology that separates a portion of the exhaust gas after combustion in an internal combustion engine and directs it to the intake side for re-combustion. Its main purpose is to reduce nitrogen oxides (NOx) in the exhaust gas and improve fuel consumption when sharing part of the load.

[0003] Currently, the mainstream approach used by automakers is to control the EGR system by setting a fixed target EGR rate based on speed and load. However, due to variations in airway performance, valve timing, and other components across mass-produced engines, the optimal tolerable EGR rate varies from engine to engine. Related technologies typically incorporate a significant safety margin when calibrating the target EGR rate to address this issue. However, this conservative calibration also prevents the engine from operating at higher EGR rates, resulting in a certain loss in fuel economy. Summary of the Invention

[0004] One of the purposes of the present application is to provide an engine control method, device, unit and storage medium to solve the problem that the calibrated EGR rate in the prior art is relatively conservative, resulting in economic losses.

[0005] In order to achieve the above objectives, the technical solutions adopted in this application are as follows:

[0006] According to a first aspect of the present application, an engine control method is provided, comprising obtaining a current combustion stability value of the engine after the engine has been operating at a target operating condition for a preset period of time, the current combustion stability value being used to characterize the combustion stability of the engine during the preset period of time. If the current combustion stability value is less than a combustion stability limit corresponding to the target operating condition, a first control strategy is executed; the first control strategy includes adjusting a current exhaust gas recirculation (EGR) rate to a first EGR rate, and, when the engine torque is controlled to be within a preset torque range, adjusting a current ignition advance angle to a first ignition advance angle; the first EGR rate is greater than the current EGR rate, and the first ignition advance angle is greater than the current ignition advance angle.

[0007] Based on the above technical measures, the engine control method provided by this application can, if the current combustion stability value does not exceed the combustion stability limit, indicate that the current engine combustion stability still has margin, and then increase the EGR rate and ignition advance angle to operate the engine at a higher EGR rate. In other words, the engine control method provided by this application can reduce fuel consumption while ensuring safe engine operation.

[0008] In one possible embodiment, the method further includes: after executing the first control strategy, updating a current combustion stability value of the engine to obtain an updated current combustion stability value. If the updated current combustion stability value is less than a combustion stability limit value and the first injection pulse width is less than a second injection pulse width, repeatedly executing the first control strategy; the first injection pulse width is the injection pulse width of the engine after executing the first control strategy, and the second injection pulse width is the injection pulse width of the engine before executing the first control strategy.

[0009] According to the above technical means, after executing the first control strategy, the present application can, when the updated current combustion stability value does not exceed the combustion stability limit, indicate that the current engine combustion stability still has margin, and when the first injection pulse width is smaller than the second injection pulse width, indicate that the engine fuel consumption is reduced, and then increase the EGR rate and ignition advance angle to make the engine run at a higher EGR rate.

[0010] In one possible embodiment, the method further includes: after executing the first control strategy, updating a current combustion stability value of the engine to obtain an updated current combustion stability value. If the updated current combustion stability value is greater than or equal to the combustion stability limit value, or if the first injection pulse width is greater than or equal to the second injection pulse width, determining the current EGR rate during the previous execution of the first control strategy as the optimal EGR rate corresponding to the target operating condition, and determining the current ignition advance angle during the previous execution of the first control strategy as the optimal ignition advance angle corresponding to the target operating condition; the first injection pulse width is the injection pulse width of the engine after executing the first control strategy, and the second injection pulse width is the injection pulse width of the engine before executing the first control strategy.

[0011] Based on the above technical measures, the present application can restore the EGR rate and ignition advance angle to their pre-adjustment levels after executing the first control strategy, if the engine control device determines that the current combustion stability has exceeded the combustion stability limit for the target operating condition, thereby ensuring safe engine operation. Simultaneously, the application also confirms changes in the injection pulse width before and after executing the first control strategy. If the injection pulse width increases, the EGR rate and ignition advance angle are restored to their pre-adjustment levels to avoid increased fuel consumption.

[0012] In a possible embodiment, the above method further includes: storing the optimal EGR rate and the optimal ignition advance angle corresponding to the target operating condition, so that when the engine is in the target operating condition, the optimal EGR rate and the optimal ignition advance angle are called for operation.

[0013] According to the above technical means, the present application can directly call the optimal EGR rate and optimal ignition advance angle when the engine runs to the target operating conditions again, ensuring that the engine can run safely in a more energy-efficient manner.

[0014] In one possible embodiment, the above method also includes: executing a second control strategy when the current combustion stability value is greater than or equal to the combustion stability limit value; the second control strategy includes adjusting the current EGR rate to a second EGR rate, and, when controlling the engine torque to be in a preset torque range, adjusting the current ignition advance angle to a second ignition advance angle; the second EGR rate is less than the current EGR rate, and the second ignition advance angle is less than the current ignition advance angle.

[0015] According to the above technical means, the present application can, when the current combustion stability value is greater than or equal to the combustion stability limit value, indicate that the current engine combustion stability no longer meets the requirements of the engineered product, and continue to operate at a larger EGR rate and ignition advance angle, which will cause jitter and misfire problems, and then by reducing the EGR rate and ignition advance angle, the engine can be operated at an EGR rate that is consistent with the current state of the engine, avoiding frequent engine jitter or misfire problems, thereby ensuring the safe operation of the vehicle.

[0016] In one possible implementation, the method further includes: after executing the second control strategy, updating a current combustion stability value of the engine to obtain an updated current combustion stability value, and repeating the second control strategy when the updated current combustion stability value is greater than or equal to the combustion stability limit.

[0017] According to the above technical means, when the updated current combustion stability value is still greater than or equal to the combustion stability limit, it indicates that the current engine combustion stability still does not meet the requirements of the engineered product. Then, by repeatedly executing the second control strategy, the EGR rate and ignition advance angle are continuously reduced until the combustion stability of the engine is less than the combustion stability limit, so that the engine operates at an EGR rate that is consistent with the current state of the engine, avoiding frequent engine shaking or misfire problems, and ensuring the safe operation of the vehicle.

[0018] In one possible embodiment, the method further includes: after executing the second control strategy, updating a current combustion stability value of the engine to obtain an updated current combustion stability value. If the updated current combustion stability value is less than a combustion stability limit, determining a second EGR rate during a previous execution of the second control strategy as an optimal EGR rate corresponding to the target operating condition, and determining a second ignition advance angle during a previous execution of the second control strategy as an optimal ignition advance angle corresponding to the target operating condition.

[0019] According to the above technical means, the present application can, when the current combustion stability value is less than the combustion stability limit value, indicate that the current engine combustion stability can meet the requirements of the engineered product. If the EGR rate is continuously reduced, the engine fuel consumption will increase. Therefore, when the current combustion stability value is less than the combustion stability limit value, operating the engine with the adjusted second EGR rate and second ignition advance angle can ensure that the engine operates safely in a more economical manner.

[0020] In a possible embodiment, the above method further includes: storing the optimal EGR rate and the optimal ignition advance angle corresponding to the target operating condition, so that when the engine is in the target operating condition, the optimal EGR rate and the optimal ignition advance angle are called for operation.

[0021] According to the above technical means, the present application can directly call the optimal EGR rate and optimal ignition advance angle when the engine runs to the target operating conditions again, ensuring that the engine can run safely in a more energy-efficient manner.

[0022] In a possible implementation, the method further includes: controlling the engine torque to be within a preset torque range according to a throttle or a wastegate valve of the engine.

[0023] According to the above technical means, the present application can ensure that the engine operates in a relatively stable working condition, ensuring that the obtained optimal EGR rate and optimal ignition advance angle correspond to the target working condition.

[0024] In one possible implementation, the method further includes obtaining an operating state of the engine, where the operating state includes information about the engine's speed over a preset time period, or information about the engine's torque over a preset time period, and determining a current combustion stability value of the engine based on the operating state of the engine.

[0025] According to the above technical means, the present application can obtain the current combustion stability value of the engine.

[0026] In one possible implementation, the method further includes: adjusting the current EGR rate based on a first threshold to obtain an adjusted first EGR rate; and adjusting the current ignition advance angle based on a second threshold until the engine is at a knock boundary to obtain an adjusted first ignition advance angle.

[0027] According to the above technical means, the present application can achieve an increase in the EGR rate and the ignition advance angle.

[0028] In one possible implementation, the method further includes: adjusting the current EGR rate based on a third threshold to obtain an adjusted second EGR rate; and adjusting the current ignition advance angle based on a fourth threshold until the engine is at a knock boundary to obtain an adjusted second ignition advance angle.

[0029] According to the above technical means, the present application can achieve the reduction of EGR rate and ignition advance angle.

[0030] According to a second aspect provided by the present application, an engine control device is provided, comprising an acquisition unit and a processing unit. The acquisition unit is configured to acquire a current combustion stability value of the engine after the engine has been operating at a target operating condition for a preset period of time, wherein the current combustion stability value is used to characterize the combustion stability of the engine within the preset period of time. The processing unit is configured to execute a first control strategy when the current combustion stability value is less than a combustion stability limit value corresponding to the target operating condition; the first control strategy comprises adjusting the current exhaust gas recirculation (EGR) rate to a first EGR rate, and, when the engine torque is controlled to be within a preset torque range, adjusting the current ignition advance angle to a first ignition advance angle; the first EGR rate is greater than the current EGR rate, and the first ignition advance angle is greater than the current ignition advance angle.

[0031] In one possible embodiment, the above-mentioned processing unit is also used to update the current combustion stability value of the engine to obtain an updated current combustion stability value; when the updated current combustion stability value is less than the combustion stability limit value and the first injection pulse width is less than the second injection pulse width, the first control strategy is repeatedly executed; the first injection pulse width is the injection pulse width of the engine after executing the first control strategy, and the second injection pulse width is the injection pulse width of the engine before executing the first control strategy.

[0032] In one possible embodiment, the above-mentioned processing unit is also used to update the current combustion stability value of the engine to obtain an updated current combustion stability value; when the updated current combustion stability value is greater than or equal to the combustion stability limit value, or the first injection pulse width is greater than or equal to the second injection pulse width, the current EGR rate during the last execution of the first control strategy is determined as the optimal EGR rate corresponding to the target operating condition, and the current ignition advance angle during the last execution of the first control strategy is determined as the optimal ignition advance angle corresponding to the target operating condition; the first injection pulse width is the injection pulse width of the engine after executing the first control strategy, and the second injection pulse width is the injection pulse width of the engine before executing the first control strategy.

[0033] In one possible embodiment, the above-mentioned engine control device also includes a storage unit, which is also used to store the optimal EGR rate and optimal ignition advance angle corresponding to the target operating condition, so that when the engine is in the target operating condition, the optimal EGR rate and optimal ignition advance angle are called for operation.

[0034] In one possible embodiment, the above-mentioned processing unit is also used to execute a second control strategy when the current combustion stability value is greater than or equal to the combustion stability limit value; the second control strategy includes adjusting the current EGR rate to a second EGR rate, and, when controlling the engine torque to be in a preset torque range, adjusting the current ignition advance angle to a second ignition advance angle; the second EGR rate is less than the current EGR rate, and the second ignition advance angle is less than the current ignition advance angle.

[0035] In a possible implementation, the processing unit is further configured to update a current combustion stability value of the engine to obtain an updated current combustion stability value; and when the updated current combustion stability value is greater than or equal to a combustion stability limit value, repeatedly executing the second control strategy.

[0036] In one possible embodiment, the above-mentioned processing unit is also used to update the current combustion stability value of the engine to obtain an updated current combustion stability value; when the updated current combustion stability value is less than the combustion stability limit value, the second EGR rate during the last execution of the second control strategy is determined as the optimal EGR rate corresponding to the target operating condition, and the second ignition advance angle during the last execution of the second control strategy is determined as the optimal ignition advance angle corresponding to the target operating condition.

[0037] In a possible embodiment, the above-mentioned storage unit is also used to store the optimal EGR rate and the optimal ignition advance angle corresponding to the target operating condition, so that when the engine is in the target operating condition, the optimal EGR rate and the optimal ignition advance angle are called for operation.

[0038] In a possible implementation, the processing unit is specifically configured to control the engine torque to be within a preset torque range according to a throttle or a wastegate valve of the engine.

[0039] In one possible embodiment, the acquisition unit is specifically used to obtain the operating status of the engine, which includes the speed information of the engine within a preset time period, or the torque information of the engine within a preset time period; and determine the current combustion stability value of the engine based on the operating status of the engine.

[0040] In one possible embodiment, the above-mentioned processing unit is specifically used to adjust the current EGR rate based on the first threshold to obtain an adjusted first EGR rate; adjust the current ignition advance angle based on the second threshold until the engine is at the knock boundary, and obtain the adjusted first ignition advance angle.

[0041] In one possible embodiment, the above-mentioned processing unit is specifically used to adjust the current EGR rate based on the third threshold to obtain an adjusted second EGR rate; adjust the current ignition advance angle based on the fourth threshold until the engine is at the knock boundary, and obtain an adjusted second ignition advance angle.

[0042] According to a third aspect of the present application, an engine control unit is provided, deployed in a vehicle. The engine control unit includes a memory and a processor, the memory and the processor being coupled; the memory is configured to store computer program code, the computer program code comprising computer instructions; when the processor executes the computer instructions, the engine control unit executes the engine control method provided in the first aspect and any possible implementation thereof.

[0043] According to the fourth aspect provided by the present application, a computer-readable storage medium is provided, in which instructions are stored. When the instructions are executed on the engine control unit, the engine control unit executes the engine control method provided by the above-mentioned first aspect and any possible implementation method thereof.

[0044] According to a fifth aspect provided by the present application, a vehicle is provided, comprising the engine control unit provided by the third aspect above.

[0045] According to the sixth aspect provided by the present application, a computer program product is provided, which includes computer instructions. When the computer instructions are run on an engine control unit, the engine control unit executes the engine control method provided by the above-mentioned first aspect and any possible implementation method thereof.

[0046] Therefore, the above technical features of this application have the following beneficial effects:

[0047] (1) If the current combustion stability value does not exceed the combustion stability limit, indicating that the current engine combustion stability still has margin, the EGR rate and ignition advance angle can be increased to enable the engine to operate at a higher EGR rate. In other words, the engine control method provided in this application can reduce the fuel consumption generated by engine operation while ensuring safe engine operation.

[0048] (2) After executing the first control strategy, if the engine control device determines that the current combustion stability has exceeded the combustion stability limit of the target operating condition, the EGR rate and ignition advance angle before the last adjustment can be restored to ensure safe engine operation. At the same time, the change in injection pulse width before and after executing the first control strategy is also confirmed. If the injection pulse width increases, the EGR rate and ignition advance angle before the last adjustment are restored to avoid increasing fuel consumption.

[0049] (3) When the current combustion stability value is greater than or equal to the combustion stability limit, it means that the current engine combustion stability no longer meets the requirements of the engineered product. Continuing to operate at a larger EGR rate and ignition advance angle will cause vibration and misfire problems. Then, by reducing the EGR rate and ignition advance angle, the engine can be operated at an EGR rate that meets the current state of the engine, avoiding frequent engine vibration or misfire problems, thereby ensuring the safe operation of the vehicle.

[0050] (4) When the current combustion stability value is less than the combustion stability limit, it indicates that the current engine combustion stability can meet the requirements of the engineered product. If the EGR rate is continuously reduced, the engine fuel consumption will increase. Therefore, when the current combustion stability value is less than the combustion stability limit, operating the engine with the adjusted second EGR rate and the second ignition advance angle can ensure that the engine operates safely in a more economical manner.

[0051] (5) When the engine is running at the target operating condition again, the optimal EGR rate and the optimal ignition advance angle can be directly called to run, ensuring that the engine can run safely in a more energy-efficient manner.

[0052] (6) The self-learning adjustment of the EGR rate is realized according to the operating conditions of the engine to obtain the current optimal EGR rate and optimal ignition angle of the engine.

[0053] It should be noted that the technical effects brought about by any implementation method in the second to sixth aspects can refer to the technical effects brought about by the corresponding implementation method in the first aspect, and will not be repeated here.

[0054] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 is a structural diagram of an engine control system according to an exemplary embodiment;

[0056] Figure 2 is a schematic diagram showing a signal interaction according to an exemplary embodiment;

[0057] Figure 3 is a flow chart showing an engine control method according to an exemplary embodiment;

[0058] Figure 4 is a flow chart showing another engine control method according to an exemplary embodiment;

[0059] Figure 5 is a flow chart showing another engine control method according to an exemplary embodiment;

[0060] Figure 6 is a flow chart showing another engine control method according to an exemplary embodiment;

[0061] Figure 7 is a flow chart showing another engine control method according to an exemplary embodiment;

[0062] Figure 8 is a flow chart showing another engine control method according to an exemplary embodiment;

[0063] Figure 9 is a flow chart showing another engine control method according to an exemplary embodiment;

[0064] Figure 10 is a flow chart showing another engine control method according to an exemplary embodiment;

[0065] Figure 11 is a flow chart showing another engine control method according to an exemplary embodiment;

[0066] Figure 12 is a flow chart showing another engine control method according to an exemplary embodiment;

[0067] Figure 13 is a schematic diagram showing a change in ignition advance angle with EGR rate according to an exemplary embodiment;

[0068] Figure 14 is a schematic diagram showing how combustion stability varies with EGR rate according to an exemplary embodiment;

[0069] Figure 15is a schematic diagram showing how fuel consumption per unit effective work varies with EGR rate according to an exemplary embodiment;

[0070] Figure 16 is a block diagram of an engine control device according to an exemplary embodiment;

[0071] Figure 17 The figure is a block diagram of an engine control unit according to an exemplary embodiment. DETAILED DESCRIPTION

[0072] The following will describe the embodiments of the present application with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand the other advantages and effects of the present application from the contents disclosed in this specification. The present application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be understood that the preferred embodiments are only for the purpose of illustrating the present application and are not intended to limit the scope of protection of the present application.

[0073] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. Therefore, the illustrations only show components related to the present application and are not drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component can be changed at will, and the component layout type may also be more complicated.

[0074] In the description of the embodiments, unless otherwise specified, “ / ” means “or”. For example, A / B can mean A or B. “And / or” in this article is merely a description of the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, “at least one” and “a plurality of” refer to two or more. Words such as “first” and “second” do not limit the quantity and execution order, and words such as “first” and “second” do not necessarily limit them to be different.

[0075] In related technologies, automakers typically retain a large safety margin when setting the target EGR rate during calibration. However, this conservative calibration approach also prevents the engine from operating at the modified EGR rate, resulting in a certain loss in fuel economy. Furthermore, with the increasing electrification of vehicles and the application of hybrid technology, the engine's operating range has narrowed, and engine operating conditions have become more stable. During this period, the generator typically controls the engine speed, making it possible to monitor the engine's combustion stability through the generator.

[0076] To address the above-mentioned issues, the present application proposes an engine control method, device, unit, and storage medium. The engine control device obtains the current combustion stability value of the engine after the engine has been operating at a target operating condition for a preset period of time. The current combustion stability value is used to characterize the combustion stability of the engine within the preset period of time. Furthermore, the engine control device executes a first control strategy when the current combustion stability value is less than the combustion stability limit corresponding to the target operating condition. The first control strategy includes adjusting the current exhaust gas recirculation (EGR) rate to a first EGR rate, and, when the engine torque is controlled to be within a preset torque range, adjusting the current ignition advance angle to a first ignition advance angle. The first EGR rate is greater than the current EGR rate, and the first ignition advance angle is greater than the current ignition advance angle.

[0077] Thus, in the engine control method provided by this application, if the current combustion stability value does not exceed the combustion stability limit, it indicates that the current engine combustion stability still has margin. Therefore, by increasing the EGR rate and ignition advance angle, the engine can operate at a higher EGR rate. In other words, the engine control method provided by this application can reduce fuel consumption while ensuring safe engine operation.

[0078] Figure 1 An engine control system is shown. The engine control method provided in the embodiment of the present application can be applied to Figure 1 The engine control system shown is used to ensure safe operation of the engine while reducing the fuel consumption generated by the engine. Figure 1 As shown, the engine control system 10 includes an engine control device 11 , an engine 12 , a generator 13 , a power electronic unit (PEU) 14 , an engine control unit (ECU) 15 , a speed sensor 16 , a knock sensor 17 and a vehicle 18 .

[0079] The engine control device 11 is deployed in the ECU 15, and the ECU 15 is connected to the engine 12, the PEU 14, the speed sensor 16, and the knock sensor 17 respectively. The generator 13 is connected to the engine 12 and the PEU 14 respectively. The engine control device 11, the engine 12, the generator 13, the power electronic unit (PEU) 14, the engine control unit (ECU) 15, the speed sensor 16, and the knock sensor 17 are deployed in the vehicle 18. In the above connection relationship, wired connection or wireless connection can be used, which is not limited in the embodiment of the present application.

[0080] It should be noted that the speed sensor 16 may be a crankshaft speed sensor. The engine control device 11 may be integrated into the ECU 15 or deployed independently, which is not specifically limited in the present embodiment.

[0081] Figure 2 A schematic diagram of signal interaction for an engine control device 11 to control an engine 12 is shown.

[0082] The engine control unit 11 may be used to receive a torque signal sent by the PEU 14 , a speed signal sent by the speed sensor 16 , and a knock signal sent by the knock sensor 17 .

[0083] Furthermore, the engine control device 11 determines a control strategy based on the acquired torque signal, speed signal and knock signal, so that the ECU 15 operates the ignition coil, EGR valve, throttle, exhaust bypass valve and injector according to the control strategy to control the engine 12.

[0084] The generator 13 may be used to monitor the torque of the engine 12 and transmit the monitored torque of the engine 12 to the PEU 14 through connection with the PEU 14 .

[0085] The PEU 14 may be configured to send a torque signal to the engine control unit 11 after receiving the torque sent by the generator 13 .

[0086] The rotation speed sensor 16 can be used to monitor the rotation speed of the engine 12 and generate a rotation speed signal to be sent to the engine control device 11 .

[0087] The knock sensor 17 can be used to monitor the knock condition of the engine 12 and generate a knock signal to send to the engine control unit 11 .

[0088] The vehicle 18 may be a fuel vehicle or a hybrid vehicle.

[0089] Figure 3 FIG. 1 is a flow chart of an engine control method according to some exemplary embodiments. In some embodiments, the engine control method can be applied to Figure 1 The engine control device 11 in the engine control system 10 is shown. In the following, the engine control method is described by taking the application of the engine control method to the engine control device 11 as an example.

[0090] like Figure 3 As shown, the engine control method provided in the embodiment of the present application includes the following S201-S203.

[0091] S201 : After the engine operates at a target operating condition for a preset period of time, the engine control device obtains a current combustion stability value of the engine.

[0092] The current combustion stability value is used to characterize the combustion stability of the engine within a preset time period, and the target operating condition is any steady-state operating condition in which the engine can operate.

[0093] As one possible implementation, the engine control device determines the engine speed change rate and torque change rate over a preset duration based on the speed signal transmitted by the speed sensor and the torque signal transmitted by the PEU, and determines whether the speed change rate and torque change rate fall within a change rate range corresponding to the target operating condition. Furthermore, if the speed change rate and torque change rate over the preset duration fall within the change rate range corresponding to the target operating condition, the engine control device determines the current combustion stability value of the engine.

[0094] In some embodiments, the engine control device determines the current combustion stability value of the engine, which can be specifically as follows: the engine control device determines the engine speed change rate within a preset time based on the engine speed signals received at multiple moments within a preset time period, and further calculates the current combustion stability value of the engine based on the engine speed change rate and the combustion stability parameters.

[0095] In other embodiments, the engine control device determines the current combustion stability value of the engine, which can be specifically: the engine control device determines the torque change rate of the engine within a preset time based on the engine torque signals at multiple moments received within a preset time period, and further calculates the current combustion stability value of the engine based on the engine torque change rate and combustion stability parameters.

[0096] It should be noted that the preset duration, the rate of change range corresponding to the target operating condition, and the combustion stability parameters can be pre-set in the engine control device by the operation and maintenance personnel of the engine control system, and the embodiments of the present application do not make specific limitations on this.

[0097] It can be understood that the greater the engine speed fluctuation or the engine torque fluctuation, the lower the combustion stability, that is, the engine speed fluctuation and the engine torque fluctuation are correlated with the engine combustion stability. The embodiment of the present application sets the combustion stability parameters to determine the engine combustion stability based on the engine speed fluctuation or the engine torque fluctuation and the combustion stability parameters.

[0098] S202: The engine control device determines the current combustion stability value and its relationship with the combustion stability limit value corresponding to the target operating condition.

[0099] As one possible implementation, the engine control device determines, based on the target operating condition, the combustion stability limit corresponding to the target operating condition from a pre-stored mapping relationship between operating conditions and combustion stability limits. Furthermore, the engine control device compares the current combustion stability value determined in step S201 with the combustion stability limit corresponding to the target operating condition to determine the magnitude relationship between the current combustion stability and the combustion stability limit.

[0100] It should be noted that the correspondence between the operating conditions and the combustion stability limit can be set in advance in the engine control device by the operation and maintenance personnel of the engine control system, and the embodiments of the present application do not specifically limit this.

[0101] S203 : When the current combustion stability value is less than the combustion stability limit value corresponding to the target operating condition, the engine control device executes the first control strategy.

[0102] Among them, the first control strategy includes adjusting the current exhaust gas recirculation EGR rate to a first EGR rate, and, while controlling the engine torque to be within a preset torque range, adjusting the current ignition advance angle to a first ignition advance angle; the first EGR rate is greater than the current EGR rate, and the first ignition advance angle is greater than the current ignition advance angle.

[0103] As a possible implementation, the engine control device, based on the relationship between the current combustion stability and the combustion stability limit determined in step S202, executes a first control strategy pre-stored in the engine control device if the current combustion stability is less than the combustion stability limit. This includes the engine control device increasing the current EGR rate to obtain a first EGR rate and increasing the current ignition advance angle to obtain a first ignition advance angle.

[0104] It should be noted that how the engine control device specifically executes the first control strategy can be referred to the subsequent description of the embodiments of this application and will not be repeated here.

[0105] It is understandable that if the current combustion stability value does not exceed the combustion stability limit, it indicates that the current engine combustion stability still has margin. Therefore, by increasing the EGR rate and ignition advance angle, the engine can be operated at a higher EGR rate. In other words, the engine control method provided in this application can operate the engine in a more economical manner, reducing fuel consumption generated by engine operation.

[0106] In one design, after executing the first control strategy, in order to ensure that the engine can operate in a more economical manner under the current working conditions, the engine control method provided by this application is as follows: Figure 4 As shown, it also includes S301-S304.

[0107] S301 : The engine control device updates a current combustion stability value of the engine to obtain an updated current combustion stability value.

[0108] As a possible implementation method, the engine control device updates the current combustion stability value based on the method for determining the current combustion stability value as recorded in the above step S201, and obtains an updated current combustion stability value after the engine runs for a preset period of time with the adjusted first EGR rate and first ignition advance angle.

[0109] S302: The engine control device determines the updated current combustion stability value and its relationship with the combustion stability limit value.

[0110] As a possible implementation method, the engine control device further compares the updated current combustion stability value determined in the above step S301 with the combustion stability limit corresponding to the target operating condition to determine the size relationship between the updated current combustion stability and the combustion stability limit.

[0111] S303: The engine control device determines the relationship between the first fuel injection pulse width and the second fuel injection pulse width.

[0112] The first fuel injection pulse width is the fuel injection pulse width of the engine after the first control strategy is executed, and the second fuel injection pulse width is the fuel injection pulse width of the engine before the first control strategy is executed.

[0113] As a possible implementation, the engine control device obtains the first injection pulse width and the second injection pulse width, and then determines the size relationship between the first injection pulse width and the second injection pulse width by comparing the first injection pulse width and the second injection pulse width.

[0114] In some embodiments, the engine control device obtains the first injection pulse width and the second injection pulse width. Specifically, the engine control device obtains the second injection pulse width before the execution of the first control strategy and the first injection pulse width after the execution of the first control strategy based on the engine operation record.

[0115] S304: The engine control device repeatedly executes the first control strategy when the updated current combustion stability value is less than the combustion stability limit value and the first injection pulse width is less than the second injection pulse width.

[0116] As a possible implementation method, the engine control device executes the first control strategy again when it determines based on the above step S302 that the updated current combustion stability value is less than the combustion stability limit value, and determines based on the above step S303 that the first injection pulse width is less than the second injection pulse width.

[0117] It should be noted that how the engine control device specifically executes the first control strategy can be referred to the subsequent description of the embodiments of this application and will not be repeated here.

[0118] It can be understood that if the updated current combustion stability value does not exceed the combustion stability limit, it indicates that the current engine combustion stability still has margin. If the first injection pulse width is smaller than the second injection pulse width, it indicates that the engine fuel consumption has decreased. Therefore, by increasing the EGR rate and ignition advance angle, the engine can operate at a higher EGR rate. Furthermore, after repeatedly executing the first control strategy, if the conditions for repeated execution are still met, the strategy can be repeated again to further reduce engine fuel consumption. In other words, the engine control method provided in this application can operate the engine in a more economical manner, reducing fuel consumption.

[0119] In one design, after executing the first control strategy, in order to ensure that the engine can operate safely under the current working conditions, the engine control method provided by this application is as follows: Figure 5 As shown, it also includes S401-S404.

[0120] S401: The engine control device updates a current combustion stability value of the engine to obtain an updated current combustion stability value.

[0121] S402: The engine control device determines the updated current combustion stability value and its relationship with the combustion stability limit value.

[0122] S403: The engine control device determines the relationship between the first fuel injection pulse width and the second fuel injection pulse width.

[0123] It should be noted that the specific implementation of steps S401-S403 can refer to the implementation of steps S301-S303 in the above embodiment, and will not be repeated here.

[0124] S404. When the updated current combustion stability value is greater than or equal to the combustion stability limit value, or the first injection pulse width is greater than or equal to the second injection pulse width, the engine control device determines the current ignition advance angle during the last execution of the first control strategy as the optimal ignition advance angle corresponding to the target operating condition, and determines the current EGR rate during the last execution of the first control strategy as the optimal EGR rate corresponding to the target operating condition.

[0125] As one possible implementation, if the engine control device determines in step S402 that the updated current combustion stability value is greater than or equal to the combustion stability limit value, or if the engine control device determines in step S403 that the first injection pulse width is greater than or equal to the second injection pulse width, the engine control device determines the current EGR rate and the current ignition advance angle during the last execution of the first control strategy. Furthermore, the engine control device determines the determined current EGR rate as the optimal EGR rate for the target operating condition. The engine control device also determines the determined current ignition advance angle as the optimal ignition advance angle for the target operating condition.

[0126] As another possible implementation, when the updated current combustion stability value of the engine control device is greater than or equal to the combustion stability limit value, or when the first injection pulse width is determined to be greater than or equal to the second injection pulse width, the engine control device determines the EGR rate and ignition advance angle for the engine's current operating state. Furthermore, the engine control device determines the change in the EGR rate and the change in the ignition advance angle during the last execution of the first control strategy, and determines the difference between the EGR rate for the engine's current operating state and the change in the EGR rate as the optimal EGR rate, and determines the difference between the ignition advance angle for the engine's current operating state and the change in the ignition advance angle as the optimal ignition advance angle.

[0127] In some embodiments, after the engine control device determines the optimal EGR rate and optimal ignition advance angle corresponding to the target operating condition, the engine control device establishes a mapping relationship between the target operating condition and the optimal EGR rate and optimal ignition advance angle, and stores the optimal EGR rate and optimal ignition advance angle corresponding to the target operating condition, so that when the engine is in the target operating condition, the optimal EGR rate and optimal ignition advance angle are called for operation.

[0128] It will be appreciated that in the engine control method provided in the above-described embodiment of the present application, after executing the first control strategy, the engine control device determines whether the current combustion stability has exceeded the combustion stability limit for the target operating condition. If so, the EGR rate and ignition advance angle are restored to their pre-adjustment levels to ensure safe engine operation. Simultaneously, the change in injection pulse width before and after executing the first control strategy is confirmed. If the injection pulse width increases, the EGR rate and ignition advance angle are restored to their pre-adjustment levels to avoid increased fuel consumption.

[0129] In one design, as the engine's running time increases, the combustion system's tolerance to EGR decreases due to carbon deposits and wear. If the calibrated EGR rate is at the combustion stability boundary, some products may not be able to tolerate so much exhaust gas, resulting in jitter and misfire problems. In order to ensure the safe operation of the engine, the engine control method provided in the embodiment of the present application is combined with Figure 3,like Figure 6 As shown, it also includes S501.

[0130] S501 : When a current combustion stability value is greater than or equal to a combustion stability limit value, the engine control device executes a second control strategy.

[0131] Among them, the second control strategy includes adjusting the current EGR rate to a second EGR rate, and, while controlling the engine torque to be within a preset torque range, adjusting the current ignition advance angle to a second ignition advance angle; the second EGR rate is less than the current EGR rate, and the second ignition advance angle is less than the current ignition advance angle.

[0132] As a possible implementation, the engine control device, based on the magnitude relationship between the current combustion stability and the combustion stability limit determined in step S202, executes a second control strategy pre-stored in the engine control device when the current combustion stability is greater than or equal to the combustion stability limit. This includes the engine control device reducing the current EGR rate to obtain a second EGR rate and reducing the current ignition advance angle to obtain a second ignition advance angle.

[0133] It should be noted that how the engine control device specifically executes the second control strategy can be referred to the subsequent description of the embodiments of this application and will not be repeated here.

[0134] It can be understood that when the current combustion stability value is greater than or equal to the combustion stability limit, it means that the current engine combustion stability no longer meets the requirements of the engineered product. Continuing to operate at a larger EGR rate and ignition advance angle will cause jitter and misfire problems. Therefore, by reducing the EGR rate and ignition advance angle, the engine can operate at an EGR rate that matches the current state of the engine, avoiding frequent engine jitter or misfire problems, thereby ensuring the safe operation of the vehicle.

[0135] In one design, after executing the second control strategy, in order to ensure the safe operation of the engine, the engine control method provided by this application is as follows: Figure 7 As shown, it also includes S601-S603.

[0136] S601: The engine control device updates a current combustion stability value of the engine to obtain an updated current combustion stability value.

[0137] S602: The engine control device determines the updated current combustion stability value and its relationship with the combustion stability limit value.

[0138] It should be noted that the specific implementation of steps S601-S602 can refer to the implementation of steps S301-S302 in the above embodiment, and will not be repeated here.

[0139] S603: When the updated current combustion stability value is greater than or equal to the combustion stability limit value, the engine control device repeatedly executes the second control strategy.

[0140] As a possible implementation manner, the engine control device executes the second control strategy again when it is determined based on step S602 that the updated current combustion stability value is greater than or equal to the combustion stability limit value.

[0141] It should be noted that how the engine control device specifically executes the second control strategy can be referred to the subsequent description of the embodiments of this application and will not be repeated here.

[0142] It can be understood that when the updated current combustion stability value is still greater than or equal to the combustion stability limit, it means that the current engine combustion stability still does not meet the requirements of the engineered product. Then, by repeatedly executing the second control strategy, the EGR rate and the ignition advance angle are continuously reduced until the combustion stability of the engine is less than the combustion stability limit, so that the engine runs at an EGR rate that is consistent with the current state of the engine, avoiding frequent engine shaking or misfire problems, and ensuring the safe operation of the vehicle.

[0143] In one design, after executing the second control strategy, in order to determine the optimal EGR rate and optimal ignition advance angle corresponding to the current target operating condition, the engine control method provided by this application is as follows: Figure 8 As shown, it also includes S701-S703.

[0144] S701: The engine control device updates the current combustion stability value of the engine to obtain an updated current combustion stability value.

[0145] S702: The engine control device determines the updated current combustion stability value and its relationship with the combustion stability limit value.

[0146] It should be noted that the specific implementation of steps S701-S702 can refer to the implementation of steps S301-S302 in the above embodiment, and will not be repeated here.

[0147] S703. When the updated current combustion stability value is less than the combustion stability limit value, the engine control device determines the second EGR rate during the last execution of the second control strategy as the optimal EGR rate corresponding to the target operating condition, and determines the second ignition advance angle during the last execution of the second control strategy as the optimal ignition advance angle corresponding to the target operating condition.

[0148] As a possible implementation, if the engine control device determines in step S702 that the updated current combustion stability value is less than the combustion stability limit, it determines the second EGR rate and second ignition advance angle during the last execution of the second control strategy. Furthermore, the engine control device determines the determined second EGR rate as the optimal EGR rate for the target operating condition. The engine control device also determines the determined second ignition advance angle as the optimal ignition advance angle for the target operating condition.

[0149] In some embodiments, after the engine control device determines the optimal EGR rate and optimal ignition advance angle corresponding to the target operating condition, the engine control device establishes a mapping relationship between the target operating condition and the optimal EGR rate and optimal ignition advance angle, and stores the optimal EGR rate and optimal ignition advance angle corresponding to the target operating condition, so that when the engine is in the target operating condition, the optimal EGR rate and optimal ignition advance angle are called for operation.

[0150] It can be understood that when the current combustion stability value is less than the combustion stability limit, it means that the current engine combustion stability can meet the requirements of engineered products. If the EGR rate is continuously reduced, the engine fuel consumption will increase. Therefore, when the current combustion stability value is less than the combustion stability limit, operating the engine with the adjusted second EGR rate and second ignition advance angle can ensure that the engine operates safely in a more economical manner.

[0151] In one design, in order to enable the engine control device to control the engine torque to be within a preset torque range when adjusting the engine's EGR rate and ignition advance angle, the engine control method provided in this application also includes: the engine control device controls the engine torque to be within a preset torque range according to the engine's throttle or exhaust bypass valve.

[0152] It should be noted that the preset torque range can be set in advance in the engine control device by the operation and maintenance personnel of the engine control system, and the embodiment of the present application does not specifically limit this.

[0153] Specifically, if adjusting the engine's EGR rate and ignition advance angle results in an increase in torque, the engine control device controls the throttle to decrease or controls the wastegate valve to increase. If adjusting the engine's EGR rate and ignition advance angle results in an increase in torque, the engine control device controls the throttle to increase or controls the wastegate valve to increase.

[0154] It should be noted that the above-mentioned engine control device controls the throttle or exhaust bypass valve to adjust the size. It can only choose one method to adjust the torque, or it can control the throttle and exhaust bypass valve at the same time to adjust the torque. The embodiment of the present application does not make specific limitations on this.

[0155] For example, when the torque increases, after the engine control device controls the throttle to be reduced to the minimum state, if it is still impossible to ensure that the torque is within the preset torque range, the engine control device further controls the exhaust bypass valve to increase to ensure that the torque is within the preset torque range.

[0156] In one design, a method for obtaining the current combustion stability value of the engine is provided, such as Figure 9 As shown, the engine control method provided by this application specifically includes S801-S802.

[0157] S801: The engine control device obtains the operating status of the engine.

[0158] The operating status includes the speed information of the engine within a preset time period, or the torque information of the engine within a preset time period.

[0159] As a possible implementation method, the engine control device receives the speed signal sent by the speed sensor to determine the speed information of the engine within a preset time, and receives the torque signal sent by the PEU to determine the torque information of the engine within a preset time.

[0160] S802: The engine control device determines a current combustion stability value of the engine according to the operating state of the engine.

[0161] As a possible implementation method, the engine control device calculates the standard deviation based on the speed information at each moment within a preset time period, and determines the current combustion stability value based on the calculated speed standard deviation and the preset combustion stability parameter.

[0162] As another possible implementation, the engine control device calculates the standard deviation based on the torque information at each moment within a preset time period, and determines the current combustion stability value based on the calculated torque standard deviation and a preset combustion stability parameter.

[0163] It can be understood that the greater the engine speed fluctuation or the engine torque fluctuation, the lower the combustion stability, that is, the engine speed fluctuation and the engine torque fluctuation are correlated with the engine combustion stability. The embodiment of the present application sets the combustion stability parameters to determine the engine combustion stability based on the engine speed fluctuation or the engine torque fluctuation and the combustion stability parameters.

[0164] In one design, the engine implements a first control strategy, such as Figure 10 As shown, including S901-S902.

[0165] S901: The engine control device adjusts the current EGR rate based on a first threshold to obtain an adjusted first EGR rate.

[0166] As a possible implementation manner, the engine control device increases the first threshold value based on the current EGR rate, and determines the sum of the current EGR rate and the first threshold value as the adjusted first EGR rate.

[0167] It should be noted that the first threshold value may be pre-set in the engine control device by the operation and maintenance personnel of the engine control system, for example, it may be 0.5%, 1%, etc., and this embodiment of the present application does not specifically limit this.

[0168] S902: The engine control device adjusts the current ignition advance angle based on the second threshold until the engine is at the knock boundary, thereby obtaining an adjusted first ignition advance angle.

[0169] As one possible implementation, the engine control device increases the second threshold value based on the current ignition advance angle and, based on the knock signal transmitted by the knock sensor, determines whether the engine is currently on the knock boundary. Furthermore, if the engine is not on the knock boundary, the engine control device continues to increase the second threshold value. If the engine is on the knock boundary, the engine control device stops increasing the second threshold value and determines the current ignition advance angle after the second threshold value is increased as the adjusted first ignition advance angle.

[0170] It should be noted that the second threshold value can be pre-set in the engine control device by the operation and maintenance personnel of the engine control system, for example, it can be 0.5°, 1°, etc., and this embodiment of the present application does not specifically limit this.

[0171] In one design, the engine implements a second control strategy, such as Figure 11 As shown, including S1001-S1002.

[0172] S1001: The engine control device adjusts the current EGR rate based on a third threshold to obtain an adjusted second EGR rate.

[0173] As a possible implementation manner, the engine control device reduces the third threshold value based on the current EGR rate, and determines the difference between the current EGR rate and the third threshold value as the adjusted second EGR rate.

[0174] It should be noted that the third threshold value may be the same as the first threshold value or different from the first threshold value. Specifically, it may be set in advance in the engine control device by the operation and maintenance personnel of the engine control system. The embodiment of the present application does not make any specific limitation on this.

[0175] S1002: The engine control device adjusts the current ignition advance angle based on a fourth threshold value until the engine is at a knock boundary, thereby obtaining an adjusted second ignition advance angle.

[0176] As one possible implementation, the engine control device reduces the fourth threshold value based on the current ignition advance angle and determines whether the engine is currently on the knock boundary based on the knock signal transmitted by the knock sensor. Furthermore, if the engine is not on the knock boundary, the engine control device continues to reduce the fourth threshold value. If the engine is on the knock boundary, the engine control device stops reducing the fourth threshold value and determines the current ignition advance angle after reducing the fourth threshold value as the adjusted second ignition advance angle.

[0177] It should be noted that the fourth threshold value may be the same as the second threshold value or different from the second threshold value. Specifically, it may be set in advance in the engine control device by the operation and maintenance personnel of the engine control system. The embodiment of the present application does not make any specific limitation on this.

[0178] In one design, in combination with the above embodiments of the present application, and the attached Figure 3 -Attached Figure 11 , the engine control method provided by the embodiment of the present application is as follows Figure 12 As shown, including S1-S11.

[0179] S1. After the engine operates at a target operating condition for a preset period of time, the engine control device obtains a current combustion stability value of the engine.

[0180] S2. The engine control device determines the current combustion stability value and its relationship with the combustion stability limit value corresponding to the target operating condition.

[0181] It should be noted that if the engine control device determines that the current combustion stability value is less than the combustion stability limit value, step S3 is executed; if the engine control device determines that the current combustion stability value is greater than or equal to the combustion stability limit value, step S7 is executed.

[0182] S3. The engine control device executes the first control strategy.

[0183] S4. After the engine control device executes the first control strategy, the engine control device updates the current combustion stability value of the engine to obtain an updated current combustion stability value.

[0184] S5. The engine control device determines the updated current combustion stability value and its relationship with the combustion stability limit value, and determines the relationship between the first injection pulse width and the second injection pulse width.

[0185] It should be noted that if the engine control device determines that the updated current combustion stability value is less than the combustion stability limit value and the first injection pulse width is less than the second injection pulse width, step S3 is executed; otherwise, step S6 is executed.

[0186] S6. The engine control device determines the current ignition advance angle during the last execution of the first control strategy as the optimal ignition advance angle corresponding to the target operating condition, and determines the current EGR rate during the last execution of the first control strategy as the optimal EGR rate corresponding to the target operating condition. Then, step S11 is executed.

[0187] S7. The engine control device executes the second control strategy.

[0188] S8. After the engine control device executes the second control strategy, the engine control device updates the current combustion stability value of the engine to obtain an updated current combustion stability value.

[0189] S9. The engine control device determines the updated current combustion stability value and its relationship with the combustion stability limit value.

[0190] It should be noted that if the engine control device determines that the updated current combustion stability value is less than the combustion stability limit value and the first injection pulse width is less than the second injection pulse width, step S7 is executed; otherwise, step S10 is executed.

[0191] S10: The engine control device determines the second EGR rate during the last execution of the second control strategy as the optimal EGR rate corresponding to the target operating condition, and determines the second ignition advance angle during the last execution of the second control strategy as the optimal ignition advance angle corresponding to the target operating condition. The process then proceeds to step S11.

[0192] S11. The engine control device stores the optimal EGR rate and the optimal ignition advance angle corresponding to the target operating condition, so that when the engine is in the target operating condition, the optimal EGR rate and the optimal ignition advance angle are called for operation.

[0193] It should be noted that the specific implementation of the engine control method in the above steps S1-S11 can refer to the description in the above embodiments of the present disclosure, and will not be repeated here.

[0194] For example, when the engine speed is 2800 rpm and the torque is 95 Nm, the relationship between the ignition advance angle and the EGR rate is as follows: Figure 13 As shown; the relationship between combustion stability and EGR rate is as follows Figure 14 The relationship between the fuel consumption per unit effective work (Brake Specific Fuel Consumption, BSFC) and the EGR rate is shown as follows: Figure 15 shown.

[0195] The above mainly introduces the solution provided by the embodiment of the present application from the perspective of method. In order to realize the above functions, the engine control device or engine control unit includes hardware structures and / or software modules corresponding to the execution of each function. It should be easy for those skilled in the art to realize that, in combination with the units and algorithm steps of each example described in the embodiments disclosed herein, the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in the form of hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0196] The embodiment of the present application can, according to the above method, exemplarily divide the engine control device or engine control unit into functional modules. For example, the engine control device or engine control unit can include various functional modules corresponding to the various functional divisions, or two or more functions can be integrated into one processing module. The above-mentioned integrated modules can be implemented in the form of hardware or in the form of software functional modules. It should be noted that the division of modules in the embodiment of the present application is schematic and is only a logical functional division. In actual implementation, there may be other division methods.

[0197] Figure 16 This is a schematic diagram of the structure of an engine control device provided in an embodiment of the present application. The engine control device is used to execute the above-mentioned engine control method. Figure 16 As shown, the engine control device 110 includes an acquisition unit 1101 and a processing unit 1102 .

[0198] The acquisition unit 1101 is used to acquire a current combustion stability value of the engine after the engine runs at a target operating condition for a preset time. The current combustion stability value is used to represent the combustion stability of the engine within the preset time.

[0199] Processing unit 1102 is used to execute a first control strategy when a current combustion stability value is less than a combustion stability limit value corresponding to a target operating condition; the first control strategy includes adjusting a current exhaust gas recirculation (EGR) rate to a first EGR rate, and adjusting a current ignition advance angle to a first ignition advance angle when controlling the engine torque to be within a preset torque range; the first EGR rate is greater than the current EGR rate, and the first ignition advance angle is greater than the current ignition advance angle.

[0200] Optionally, the processing unit 1102 is also used to update the current combustion stability value of the engine to obtain an updated current combustion stability value; when the updated current combustion stability value is less than the combustion stability limit value and the first injection pulse width is less than the second injection pulse width, the first control strategy is repeatedly executed; the first injection pulse width is the injection pulse width of the engine after executing the first control strategy, and the second injection pulse width is the injection pulse width of the engine before executing the first control strategy.

[0201] Optionally, the processing unit 1102 is also used to update the current combustion stability value of the engine to obtain an updated current combustion stability value; when the updated current combustion stability value is greater than or equal to the combustion stability limit value, or the first injection pulse width is greater than or equal to the second injection pulse width, the current EGR rate during the last execution of the first control strategy is determined as the optimal EGR rate corresponding to the target operating condition, and the current ignition advance angle during the last execution of the first control strategy is determined as the optimal ignition advance angle corresponding to the target operating condition; the first injection pulse width is the injection pulse width of the engine after executing the first control strategy, and the second injection pulse width is the injection pulse width of the engine before executing the first control strategy.

[0202] Optionally, the above-mentioned engine control device also includes a storage unit 1103, which is also used to store the optimal EGR rate and optimal ignition advance angle corresponding to the target operating condition, so that when the engine is in the target operating condition, the optimal EGR rate and optimal ignition advance angle are called for operation.

[0203] Optionally, the processing unit 1102 is also used to execute a second control strategy when the current combustion stability value is greater than or equal to the combustion stability limit value; the second control strategy includes adjusting the current EGR rate to a second EGR rate, and adjusting the current ignition advance angle to a second ignition advance angle when the engine torque is controlled to be in a preset torque range; the second EGR rate is less than the current EGR rate, and the second ignition advance angle is less than the current ignition advance angle.

[0204] Optionally, the processing unit 1102 is further configured to update a current combustion stability value of the engine to obtain an updated current combustion stability value; and when the updated current combustion stability value is greater than or equal to a combustion stability limit value, repeatedly executing the second control strategy.

[0205] Optionally, the processing unit 1102 is also used to update the current combustion stability value of the engine to obtain an updated current combustion stability value; when the updated current combustion stability value is less than the combustion stability limit value, the second EGR rate in the process of the last execution of the second control strategy is determined as the optimal EGR rate corresponding to the target operating condition, and the second ignition advance angle in the process of the last execution of the second control strategy is determined as the optimal ignition advance angle corresponding to the target operating condition.

[0206] Optionally, the storage unit 1103 is also used to store the optimal EGR rate and the optimal ignition advance angle corresponding to the target operating condition, so that when the engine is in the target operating condition, the optimal EGR rate and the optimal ignition advance angle are called for operation.

[0207] Optionally, the processing unit 1102 is specifically configured to control the engine torque to be within a preset torque range according to a throttle or an exhaust bypass valve of the engine.

[0208] Optionally, the acquisition unit 1101 is specifically used to obtain the operating status of the engine, which includes the speed information of the engine within a preset time period, or the torque information of the engine within a preset time period; and determine the current combustion stability value of the engine based on the operating status of the engine.

[0209] Optionally, the processing unit 1102 is specifically configured to adjust the current EGR rate based on a first threshold value to obtain an adjusted first EGR rate; and adjust the current ignition advance angle based on a second threshold value until the engine is at a knock boundary to obtain an adjusted first ignition advance angle.

[0210] Optionally, the processing unit 1102 is specifically configured to adjust the current EGR rate based on a third threshold value to obtain an adjusted second EGR rate; and adjust the current ignition advance angle based on a fourth threshold value until the engine is at a knock boundary to obtain an adjusted second ignition advance angle.

[0211] Regarding the apparatus in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method, and will not be elaborated here.

[0212] Figure 17 FIG. 1 is a block diagram of an engine control unit according to an exemplary embodiment. Figure 17 As shown, the engine control unit 120 includes but is not limited to: a processor 1201 and a memory 1202 .

[0213] The memory 1202 is used to store executable instructions of the processor 1201. It is understood that the processor 1201 is configured to execute instructions to implement the engine control method in the above embodiment.

[0214] It should be noted that those skilled in the art can understand that Figure 17 The engine control unit structure shown in the figure does not limit the engine control unit. The engine control unit may include Figure 17 More or fewer components may be shown, or certain components may be combined, or the components may be arranged differently.

[0215] Processor 1201 is the control center of the engine control unit. It utilizes various interfaces and lines to connect the various parts of the entire engine control unit. By running or executing software programs and / or modules stored in memory 1202 and accessing data stored in memory 1202, it performs various engine control unit functions and processes data, thereby providing overall monitoring of the engine control unit. Processor 1201 may include one or more processing units. Optionally, processor 1201 may integrate an application processor and a modem processor, wherein the application processor primarily processes the operating system, user interface, and application programs, while the modem processor primarily handles wireless communications. It is understood that the modem processor may not be integrated into processor 1201.

[0216] Memory 1202 can be used to store software programs and various data. Memory 1202 may primarily include a program storage area and a data storage area. The program storage area may store an operating system and application programs required by at least one functional module (e.g., a determination unit, a processing unit, etc.). Furthermore, memory 1202 may include high-speed random access memory and non-volatile memory, such as at least one disk storage device, a flash memory device, or other volatile solid-state storage device.

[0217] In an exemplary embodiment, a computer-readable storage medium including instructions is further provided, such as a memory 1202 including instructions. The instructions can be executed by the processor 1201 of the engine control unit 120 to implement the engine control method in the above embodiment.

[0218] In actual implementation, Figure 16 The functions of the acquisition unit 1101, the processing unit 1102, and the storage unit 1103 can all be accomplished by Figure 17 The processor 1201 in the embodiment calls the computer program stored in the memory 1202. The specific execution process can be referred to the description of the engine control method in the above embodiment, which will not be repeated here.

[0219] Optionally, the computer-readable storage medium may be a non-temporary computer-readable storage medium, for example, the non-temporary computer-readable storage medium may be a read-only memory (ROM), a random access memory (RAM), a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, etc.

[0220] In an exemplary embodiment, the present application also provides a vehicle including the above-mentioned engine control unit.

[0221] In an exemplary embodiment, the present application also provides a computer program product including one or more instructions, which can be executed by the processor 1201 of the engine control unit to implement the engine control method in the above embodiment.

[0222] It should be noted that when the instructions in the above-mentioned computer-readable storage medium or one or more instructions in the computer program product are executed by the processor of the engine control unit, the various processes of the above-mentioned engine control method embodiment are implemented, and the same technical effect as the above-mentioned engine control method can be achieved. To avoid repetition, they will not be repeated here.

[0223] Through the description of the above implementation methods, technical personnel in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional modules is used as an example. In actual applications, the above-mentioned functions can be distributed and completed by different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete the full classification or partial functions described above.

[0224] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of modules or units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0225] The units described as separate components may or may not be physically separate, and the components shown as units may be one physical unit or multiple physical units, that is, they may be located in one place or distributed in multiple places. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0226] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0227] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a readable storage medium. Based on this understanding, the technical solution of the embodiment of the present application is essentially or the part that contributes to the prior art or the full classification part or part of the technical solution can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions to enable a device (which can be a single-chip microcomputer, chip, etc.) or a processor (processor) to execute the full classification part or part of the steps of the various embodiments of the present application. The aforementioned storage medium includes: various media that can store program codes, such as USB flash drives, mobile hard drives, ROM, RAM, magnetic disks or optical disks.

[0228] The above are only specific embodiments of the present application, but the scope of protection of the present application is not limited thereto. Any changes or replacements within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. An engine control method, characterized in that: include: After the engine operates at the target operating condition for a preset time, obtaining a current combustion stability value of the engine, the current combustion stability value being used to characterize the combustion stability of the engine during the preset time; When the current combustion stability value is less than the combustion stability limit value corresponding to the target operating condition, executing a first control strategy; The first control strategy includes adjusting a current EGR rate to a first EGR rate, and, while controlling the engine torque to be within a preset torque range, adjusting a current ignition advance angle to a first ignition advance angle; The first EGR rate is greater than the current EGR rate, and the first ignition advance angle is greater than the current ignition advance angle.

2. The engine control method according to claim 1, characterized in that: After executing the first control strategy, the method further includes: updating the current combustion stability value of the engine to obtain an updated current combustion stability value; When the updated current combustion stability value is less than the combustion stability limit value and the first injection pulse width is less than the second injection pulse width, the first control strategy is repeatedly executed; the first injection pulse width is the injection pulse width of the engine after executing the first control strategy, and the second injection pulse width is the injection pulse width of the engine before executing the first control strategy.

3. The engine control method according to claim 1 or 2, characterized in that: After executing the first control strategy, the method further includes: updating the current combustion stability value of the engine to obtain an updated current combustion stability value; When the updated current combustion stability value is greater than or equal to the combustion stability limit, or the first injection pulse width is greater than or equal to the second injection pulse width, the current EGR rate during the last execution of the first control strategy is determined as the optimal EGR rate corresponding to the target operating condition, and the current ignition advance angle during the last execution of the first control strategy is determined as the optimal ignition advance angle corresponding to the target operating condition; the first injection pulse width is the injection pulse width of the engine after executing the first control strategy, and the second injection pulse width is the injection pulse width of the engine before executing the first control strategy.

4. The engine control method according to claim 3, characterized in that: The method further comprises: An optimal EGR rate and an optimal ignition advance angle corresponding to the target operating condition are stored so that when the engine is in the target operating condition, the optimal EGR rate and the optimal ignition advance angle are called for operation.

5. The engine control method according to claim 1, wherein: The method further comprises: When the current combustion stability value is greater than or equal to the combustion stability limit value, a second control strategy is executed; the second control strategy includes adjusting the current EGR rate to a second EGR rate, and, while controlling the engine torque to be within the preset torque range, adjusting the current ignition advance angle to a second ignition advance angle; the second EGR rate is less than the current EGR rate, and the second ignition advance angle is less than the current ignition advance angle.

6. The engine control method according to claim 5, characterized in that: After executing the second control strategy, the method further includes: updating the current combustion stability value of the engine to obtain an updated current combustion stability value; When the updated current combustion stability value is greater than or equal to the combustion stability limit value, the second control strategy is repeatedly executed.

7. The engine control method according to claim 5 or 6, characterized in that: After executing the second control strategy, the method further includes: updating the current combustion stability value of the engine to obtain an updated current combustion stability value; When the updated current combustion stability value is less than the combustion stability limit value, the second EGR rate during the last execution of the second control strategy is determined as the optimal EGR rate corresponding to the target operating condition, and the second ignition advance angle during the last execution of the second control strategy is determined as the optimal ignition advance angle corresponding to the target operating condition.

8. The engine control method according to claim 7, characterized in that: The method further comprises: An optimal EGR rate and an optimal ignition advance angle corresponding to the target operating condition are stored so that when the engine is in the target operating condition, the optimal EGR rate and the optimal ignition advance angle are called for operation.

9. The engine control method according to claim 1 or 5, characterized in that: Controlling the engine torque to be within a preset torque range includes: According to a throttle valve or a wastegate valve of the engine, the engine torque is controlled to be within the preset torque range.

10. The engine control method according to claim 1, wherein: The obtaining of the current combustion stability value of the engine includes: Acquiring the operating state of the engine, the operating state including speed information of the engine within the preset time period, or torque information of the engine within the preset time period; A current combustion stability value of the engine is determined according to an operating state of the engine.

11. The engine control method according to claim 1, characterized in that: The executing the first control strategy includes: adjusting the current EGR rate based on a first threshold to obtain an adjusted first EGR rate; The current ignition advance angle is adjusted based on a second threshold until the engine is at a knock boundary, thereby obtaining an adjusted first ignition advance angle.

12. The engine control method according to claim 5, characterized in that: The executing the second control strategy includes: adjusting the current EGR rate based on a third threshold to obtain an adjusted second EGR rate; The current ignition advance angle is adjusted based on a fourth threshold until the engine is at a knock boundary, thereby obtaining an adjusted second ignition advance angle.

13. An engine control device, characterized in that: Deployed in the engine control unit, including the acquisition unit and the processing unit; The acquiring unit is configured to acquire a current combustion stability value of the engine after the engine has been running at a target operating condition for a preset time, wherein the current combustion stability value is used to represent the combustion stability of the engine during the preset time; The processing unit is configured to execute a first control strategy when the current combustion stability value is less than the combustion stability limit value corresponding to the target operating condition; The first control strategy includes adjusting a current EGR rate to a first EGR rate, and, while controlling the engine torque to be within a preset torque range, adjusting a current ignition advance angle to a first ignition advance angle; The first EGR rate is greater than the current EGR rate, and the first ignition advance angle is greater than the current ignition advance angle.

14. An engine control unit, characterized in that: Deployed in the vehicle, including memory and processor; The memory is coupled to the processor; The memory is used to store computer program code, wherein the computer program code includes computer instructions; When the processor executes the computer instructions, the engine control unit performs the engine control method according to any one of claims 1 to 12.

15. A computer-readable storage medium storing instructions, characterized in that: When the instruction is executed on an engine control unit, the engine control unit is caused to execute the engine control method according to any one of claims 1 to 12.

16. A vehicle, characterized in that: Comprising an engine control unit as claimed in claim 14.

Images