Engine diagnostic methods, devices, and computer storage media

Abstract

This application discloses a diagnostic method, device, and computer storage medium for an engine, belonging to the field of fault diagnosis technology. The method includes: acquiring multiple actual fuel injection factors that adjust the actual fuel injection quantity of a vehicle engine in real time at preset time intervals within a preset time period; determining whether an engine fault exists by judging whether the multiple actual fuel injection factors exist under different engine operating conditions, and whether the multiple actual fuel injection factors under different engine operating conditions fall within a first fuel injection factor range corresponding to the engine operating condition and whether they fall within a preset second fuel injection factor range where the vehicle's exhaust emissions do not exceed emission limits. In this application embodiment, determining whether an engine fault exists by performing multiple conditional judgments on the actual fuel injection factors under different engine operating conditions makes engine fault diagnosis more accurate.

Description

Technical Field

[0001] This application relates to the field of fault diagnosis technology, and in particular to a diagnostic method, device and computer storage medium for an engine. Background Technology

[0002] Currently, vehicles use fuel control systems to reduce pollution in vehicle exhaust. Commonly used fuel control systems are air-fuel ratio closed-loop control systems based on wide-range oxygen sensors. The air-fuel ratio closed-loop control system can maintain the air-fuel ratio near the stoichiometric air-fuel ratio. The air-fuel ratio is used to represent the leanness or richness of the fuel mixture in the vehicle cylinder and is an important factor affecting the pollutant content in vehicle exhaust.

[0003] When an engine malfunctions, using closed-loop control of the air-fuel ratio in the fuel system will result in a significant deviation between the actual air-fuel ratio and the stoichiometric air-fuel ratio, leading to severely excessive emissions from vehicle exhaust. Therefore, engine fault diagnosis is becoming increasingly important. Summary of the Invention

[0004] This application provides a method, apparatus, and computer storage medium for diagnosing engines, which can improve the accuracy of engine fault diagnosis. The technical solution is as follows:

[0005] On the one hand, a diagnostic method for an engine is provided, the method comprising:

[0006] Multiple actual fuel supply factors are acquired in real time at preset time intervals within a preset time period. The actual fuel supply factors are used to adjust the actual fuel injection quantity of the vehicle engine.

[0007] For each of the plurality of actual fuel supply factors, a first fuel supply factor range corresponding to each actual fuel supply factor is determined and a preset second fuel supply factor range is obtained; the first fuel supply factor range is the fuel supply factor range under the engine operating condition corresponding to the actual fuel supply factor, and the second fuel supply factor range is the fuel supply factor range that ensures the vehicle's exhaust emissions do not exceed the emission limits.

[0008] Based on the first fuel supply factor range and the second fuel supply factor range corresponding to each actual fuel supply factor, it is determined whether the plurality of actual fuel supply factors meet the fault conditions. Each actual fuel supply factor corresponds to an engine operating condition. The fault conditions are: the plurality of actual fuel supply factors include multiple actual fuel supply factors under different engine operating conditions, and the multiple actual fuel supply factors under different engine operating conditions meet the target conditions. The target conditions are that there exists an actual fuel supply factor under each engine operating condition that is not located in the first fuel supply factor range corresponding to the actual fuel supply factor and is not located in the second fuel supply factor range.

[0009] If the multiple actual fuel supply factors meet the fault conditions, then the engine is determined to be faulty;

[0010] If the multiple actual fuel supply factors do not meet the fault conditions, then it is determined that the engine does not have a fault.

[0011] Optionally, determining whether the plurality of actual fuel supply factors meet the fault conditions includes:

[0012] Determine whether the plurality of actual fuel supply factors include multiple actual fuel supply factors under different engine operating conditions. If so, determine whether there is an actual fuel supply factor that satisfies the target condition among the actual fuel supply factors under each engine operating condition.

[0013] If there is an actual fuel supply factor that meets the target condition among all the actual fuel supply factors under all engine operating conditions, then it is determined that the multiple actual fuel supply factors meet the fault condition.

[0014] If no actual fuel supply factor meets the target condition under any engine operating condition, then the plurality of actual fuel supply factors are determined not to meet the fault condition.

[0015] Optionally, determining whether there exists an actual fuel supply factor that satisfies the target condition among the actual fuel supply factors under each engine operating condition includes:

[0016] For any engine operating condition, determine whether there is an actual fuel supply factor that is not within the range of the first fuel supply factor.

[0017] If not, it is determined that there is no actual fuel supply factor that meets the target condition among the actual fuel supply factors under the engine operating conditions; if yes, it is determined whether the actual fuel supply factor that is not in the range of the first fuel supply factor is not in the range of the second fuel supply factor.

[0018] If yes, it is determined that there is an actual fuel supply factor that satisfies the target condition among the actual fuel supply factors under the engine operating conditions; otherwise, it is determined that there is no actual fuel supply factor that satisfies the target condition among the actual fuel supply factors under the engine operating conditions.

[0019] Optionally, determining the first fuel supply factor range corresponding to the actual fuel supply factor includes:

[0020] Obtain the engine load rate corresponding to the actual fuel supply factor and the engine speed corresponding to the actual fuel supply factor;

[0021] The range of the first fuel supply factor is determined based on the engine load rate and the engine speed.

[0022] Optionally, the method further includes:

[0023] When the engine malfunctions, the actual fuel injection quantity of the vehicle engine is adjusted using the latest actual fuel injection factor among the plurality of actual fuel injection factors.

[0024] On the other hand, an engine diagnostic device is provided, the device comprising:

[0025] The acquisition module is used to acquire multiple actual fuel supply factors in real time at preset time intervals within a preset time period. The actual fuel supply factors are used to adjust the actual fuel injection quantity of the vehicle engine.

[0026] The determining module is used to determine a first fuel supply factor range and obtain a preset second fuel supply factor range for each of the plurality of actual fuel supply factors; the first fuel supply factor range is the fuel supply factor range under the engine operating conditions corresponding to the actual fuel supply factor, and the second fuel supply factor range is the fuel supply factor range that ensures the vehicle's exhaust emissions do not exceed the emission limits.

[0027] The first determination module is used to determine whether the plurality of actual fuel supply factors meet the fault conditions based on the first fuel supply factor range and the second fuel supply factor range corresponding to each actual fuel supply factor. Each actual fuel supply factor corresponds to an engine operating condition. The fault condition is that the plurality of actual fuel supply factors include multiple actual fuel supply factors under different engine operating conditions, and the multiple actual fuel supply factors under different engine operating conditions meet the target condition. The target condition is that there exists an actual fuel supply factor under each engine operating condition that is not located in the first fuel supply factor range corresponding to the actual fuel supply factor and is not located in the second fuel supply factor range.

[0028] The second determination module is used to determine that the engine has a fault if the plurality of actual fuel supply factors meet the fault conditions.

[0029] The third determination module is used to determine that the engine does not have a fault if the plurality of actual fuel supply factors do not meet the fault conditions.

[0030] Optionally, the first determination module includes:

[0031] The judgment submodule is used to determine whether the multiple actual fuel supply factors include multiple actual fuel supply factors under different engine operating conditions. If so, it is determined whether there is an actual fuel supply factor that meets the target condition among the actual fuel supply factors under each engine operating condition.

[0032] The first determination submodule is used to determine that if there is an actual fuel supply factor that satisfies the target condition among the actual fuel supply factors under all engine operating conditions, then the plurality of actual fuel supply factors satisfy the fault condition.

[0033] The second determination submodule is used to determine that if no actual fuel supply factor meets the target condition under any engine operating condition, the plurality of actual fuel supply factors do not meet the fault condition.

[0034] Optionally, the first determination submodule is used to:

[0035] For any engine operating condition, determine whether there is an actual fuel supply factor that is not within the range of the first fuel supply factor.

[0036] If not, it is determined that there is no actual fuel supply factor that meets the target condition among the actual fuel supply factors under the engine operating conditions; if yes, it is determined whether the actual fuel supply factor that is not in the range of the first fuel supply factor is not in the range of the second fuel supply factor.

[0037] If yes, it is determined that there is an actual fuel supply factor that satisfies the target condition among the actual fuel supply factors under the engine operating conditions; otherwise, it is determined that there is no actual fuel supply factor that satisfies the target condition among the actual fuel supply factors under the engine operating conditions.

[0038] Optionally, the determining module includes:

[0039] The acquisition submodule is used to acquire the engine load rate corresponding to the actual fuel supply factor and the engine speed corresponding to the actual fuel supply factor.

[0040] A determination submodule is used to determine the range of the first fuel supply factor based on the engine load rate and the engine speed.

[0041] Optionally, the device further includes:

[0042] The adjustment module is used to adjust the actual fuel injection quantity of the vehicle engine by using the latest actual fuel injection factor among the plurality of actual fuel injection factors when the engine malfunctions.

[0043] On the other hand, a computer-readable storage medium is provided, on which instructions are stored, which, when executed by a processor, implement any step in the above-described engine diagnostic method.

[0044] On the other hand, a computer program product containing instructions is provided that, when run on a computer, causes the computer to perform any step in the above-described engine diagnostic method.

[0045] The beneficial effects of the technical solutions provided in this application include at least the following:

[0046] In this embodiment, multiple actual fuel injection factors for adjusting the actual fuel injection quantity of a vehicle engine are acquired in real time at preset time intervals within a preset time period. The presence of different actual fuel injection factors under different engine operating conditions is determined by judging whether these factors fall within the range of a first fuel injection factor corresponding to the engine operating condition, and whether the multiple actual fuel injection factors under different engine operating conditions fall within the range of a preset second fuel injection factor used to ensure that the vehicle's exhaust emissions do not exceed emission limits. This method of determining engine malfunction by applying multiple conditional judgments to the actual fuel injection factors under different engine operating conditions makes engine fault diagnosis more accurate. Attached Figure Description

[0047] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0048] Figure 1 This is a flowchart of an engine diagnostic method provided in an embodiment of this application;

[0049] Figure 2 This is a flowchart of another engine diagnostic method provided in an embodiment of this application;

[0050] Figure 3 This is a flowchart of a method for determining the range of the first oil supply factor corresponding to the actual oil supply factor, provided in an embodiment of this application.

[0051] Figure 4 This is a table showing the correspondence between engine speed and engine debt ratio and the first fuel supply factor provided in the embodiments of this application;

[0052] Figure 5 This is a flowchart of a method for determining whether there is an actual fuel supply factor that meets the target conditions in the actual fuel supply factor under each engine operating condition, provided in an embodiment of this application.

[0053] Figure 6 This is a schematic diagram of the structure of an engine diagnostic device provided in an embodiment of this application. Detailed Implementation

[0054] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the implementation methods of this application will be further described in detail below with reference to the accompanying drawings.

[0055] Figure 1 This is a flowchart of an engine diagnostic method provided in an embodiment of this application. This embodiment illustrates the application of this engine diagnostic method to a controller. The engine diagnostic method may include the following steps:

[0056] Step 101: Acquire multiple actual fuel supply factors in real time at preset time intervals within a preset time period. The actual fuel supply factors are used to adjust the actual fuel injection quantity of the vehicle engine.

[0057] Step 102: For each actual fuel supply factor among multiple actual fuel supply factors, determine the first fuel supply factor range corresponding to each actual fuel supply factor and obtain the preset second fuel supply factor range.

[0058] Among them, the first fuel supply factor range is the fuel supply factor range under the engine operating conditions corresponding to the actual fuel supply factor, and the second fuel supply factor range is the fuel supply factor range that ensures the vehicle's exhaust emissions do not exceed the emission limits.

[0059] Step 103: Determine whether multiple actual fuel supply factors meet the fault conditions based on the first fuel supply factor range and the second fuel supply factor range corresponding to each actual fuel supply factor.

[0060] Each actual fuel supply factor corresponds to an engine operating condition. The fault condition is that the multiple actual fuel supply factors include multiple actual fuel supply factors under different engine operating conditions, and the multiple actual fuel supply factors under different engine operating conditions meet the target condition. The target condition is that there exists an actual fuel supply factor under each engine operating condition that is not located in the first fuel supply factor range corresponding to the actual fuel supply factor and is not located in the second fuel supply factor range.

[0061] Step 104: If multiple actual fuel supply factors meet the fault conditions, then the engine is determined to be faulty.

[0062] Step 105: If multiple actual fuel supply factors do not meet the fault conditions, then it is determined that the engine does not have a fault.

[0063] In this embodiment, multiple actual fuel injection factors for adjusting the actual fuel injection quantity of a vehicle engine are acquired in real time at preset time intervals within a preset time period. The presence of different actual fuel injection factors under different engine operating conditions is determined by judging whether these factors fall within the range of a first fuel injection factor corresponding to the engine operating condition, and whether these factors fall within the range of a preset second fuel injection factor used to ensure that vehicle exhaust emissions do not exceed emission limits. This process determines whether an engine malfunction exists. In this embodiment, determining engine malfunction by applying multiple conditional judgments to the actual fuel injection factors under different engine operating conditions makes engine fault diagnosis more accurate.

[0064] Figure 2 This is a flowchart of an engine diagnostic method provided in an embodiment of this application. This embodiment illustrates the application of this engine diagnostic method to an engine controller. The engine diagnostic method may include the following steps:

[0065] Step 201: Acquire multiple actual oil supply factors in real time according to a preset time interval within a preset time period.

[0066] The preset time interval is set according to actual conditions; for example, it can be 100ms. Within the preset time period, one, two, or more actual fuel supply factors can be acquired at the preset time intervals. Each time a new actual fuel supply factor is acquired, engine fault diagnosis needs to be performed, thus achieving real-time engine fault diagnosis. During each engine fault diagnosis, the multiple fuel supply factors acquired within the preset time period are used to determine whether the engine is faulty. When an engine fault is determined, the fault diagnosis stops.

[0067] In the embodiments of this application, the actual fuel injection factor is used to adjust the actual fuel injection quantity of the vehicle engine. The actual fuel injection factor can be obtained from the fuel supply system. The specific method for determining the actual fuel injection factor obtained from the fuel supply system is as follows: During engine operation, a fuel adjustment coefficient is calculated by a control algorithm using the deviation between the theoretical air-fuel ratio and the actual air-fuel ratio. Then, the fuel adjustment coefficient is subtracted from 1 to obtain a value. This value is added to the correction signal value of the voltage of the oxygen sensor after the three-way catalytic converter to obtain the target value. This target value is integrated using an integrator in a visualization simulation tool, such as a K integrator in Simulink, at preset time intervals. The fuel adjustment factor obtained after integration is the actual fuel injection factor, which is a factor used to adjust the actual fuel injection quantity in the actual air-fuel ratio.

[0068] Step 202: For each actual fuel supply factor among multiple actual fuel supply factors, determine the first fuel supply factor range corresponding to each actual fuel supply factor and obtain the preset second fuel supply factor range.

[0069] The first fuel supply factor range is the range of fuel supply factors corresponding to the actual fuel supply factor under engine operating conditions, and the second fuel supply factor range is the range of fuel supply factors that ensures the vehicle's exhaust emissions do not exceed the emission limits, which can be OBD limits. The preset second fuel supply factor range is set according to actual conditions. In the embodiments of this application, the second fuel supply factor range is 0.805-1.164.

[0070] In this embodiment of the application, the engine operating condition is used to characterize the operating state of the engine. The number of types of engine operating conditions can be preset according to actual conditions. For example, the engine operating conditions may include: the first low-speed zone operating condition and the second low-speed zone operating condition of the engine operating in urban conditions, the first medium-speed zone operating condition and the second medium-speed zone operating condition of the engine operating in urban conditions, and the first high-speed zone operating condition of the engine operating in urban conditions.

[0071] For example, such as Figure 4 As shown, the first fuel supply factor corresponding to the first low-speed operating condition can be in the range of 0, and the first fuel supply factor corresponding to the second low-speed operating condition can be in the range of 1. The fuel supply factor range 0 is 0.9-1.1, and the fuel supply factor range 1 is 0.95-1.05. The first fuel supply factor corresponding to the first medium-speed operating condition can be in the range of 4, and the first fuel supply factor corresponding to the second medium-speed operating condition can be in the range of 5. Both fuel supply factors 4 and 5 are 0.9-1.1. The first fuel supply factor corresponding to the first high-speed operating condition can be in the range of 9. The fuel supply factor range 9 is 0.93-1.03.

[0072] In the embodiments of this application, each engine operating condition corresponds to an engine load rate and an engine speed, so that the engine operating condition can be distinguished according to the engine load rate and engine speed. Furthermore, the engine load rate and engine speed can correspond to the range of the first fuel supply factor, so that the first fuel supply factor corresponding to the actual fuel supply factor can be determined by the engine load rate and engine speed corresponding to the actual fuel supply factor.

[0073] In the implementation of this application, if Figure 3 As shown, the range of the first fuel supply factor corresponding to the actual fuel supply factor is determined, including steps 2021-2022, as follows:

[0074] Step 2021: Obtain the engine load rate and engine speed corresponding to the actual fuel supply factor.

[0075] The engine load factor is the ratio of the maximum effective power output at the same engine speed. The engine load factor and engine speed corresponding to the actual fuel supply factor are: the engine load factor and engine speed at the time corresponding to that actual fuel supply factor. That is, the engine load factor, engine speed, and the corresponding actual fuel supply factor all correspond to the same moment.

[0076] Step 2022: Determine the range of the first fuel supply factor based on the engine load rate and engine speed.

[0077] In the embodiments of this application, such as Figure 4 As shown, a pre-set correspondence table is used to determine the engine load rate, engine speed, and first fuel supply factor range. Based on the engine load rate and engine speed, the corresponding first fuel supply factor range is retrieved from this table. Each first fuel supply factor range corresponds to a specific engine operating condition.

[0078] It should be noted that the range of the first fuel supply factor corresponds to the engine load rate and engine speed. The range of the first fuel supply factor may be the same or different for different engine load rates and engine speeds, and can be set according to the actual situation. Furthermore, since there is a correspondence between engine load rate, engine speed, and the range of the first fuel supply factor, the first fuel supply sub-range corresponding to the actual fuel supply factor can be determined based on these two correspondences.

[0079] The following describes the specific process of determining whether multiple actual fuel supply factors meet the fault conditions based on the first fuel supply factor range and the second fuel supply factor range corresponding to each of the multiple actual fuel supply factors.

[0080] In this embodiment of the application, the fault condition is: the multiple actual fuel supply factors include actual fuel supply factors under different engine operating conditions, and the actual fuel supply factors under different engine operating conditions meet the target condition, which is that there exists an actual fuel supply factor under each engine operating condition that is not located in the first fuel supply factor range corresponding to the actual fuel supply factor and is not located in the second fuel supply factor range.

[0081] It should be noted that when determining whether multiple actual fuel supply factors meet the fault conditions, one can first determine whether the multiple actual fuel supply factors include actual fuel supply factors under different engine operating conditions, and then determine whether the actual fuel supply factors under different engine operating conditions meet the target conditions. Alternatively, one can first determine whether the actual fuel supply factors corresponding to the multiple actual fuel supply factors meet the target conditions, and then determine whether the actual fuel supply factors that meet the target conditions correspond to different engine operating conditions. Alternatively, one can determine in parallel whether the multiple actual fuel supply factors include actual fuel supply factors under different engine operating conditions and whether the multiple actual fuel supply factors meet the target conditions, as long as there are actual fuel supply factors under different engine operating conditions and there are actual fuel supply factors that meet the target conditions under each engine operating condition.

[0082] The following example illustrates how, when determining whether multiple actual fuel supply factors meet fault conditions, one can first determine whether the multiple actual fuel supply factors include actual fuel supply factors under different engine operating conditions, and then determine whether the actual fuel supply factors under different engine operating conditions meet the target conditions. The details are as follows:

[0083] Step 203: Determine whether the multiple actual fuel supply factors include multiple actual fuel supply factors under different engine operating conditions. If yes, proceed to step 204; otherwise, proceed to step 210. Step 210: End.

[0084] Here, different engine operating conditions are pre-set engine operating conditions, and there are a preset number of different engine operating conditions, which is an integer not less than 2; for example, the preset number can be 2, 3, 4, 5, etc. When the preset number is 2, there are 2 preset engine operating conditions. Then, it is determined whether there are 2 actual fuel supply factors under each of the multiple actual fuel supply factors. The actual fuel supply factor under each engine operating condition is the actual fuel supply factor collected when the engine is running under that engine operating condition, and each actual fuel supply factor corresponds to one engine operating condition.

[0085] It should be noted that multiple actual fuel supply factors under different engine operating conditions refer to multiple actual fuel supply factors corresponding to at least two engine operating conditions, and any one of the multiple actual fuel supply factors corresponding to at least two engine operating conditions corresponds to only one engine operating condition.

[0086] In this embodiment of the application, the preset number of engine operating conditions include at least two of the following: engine operating in the low-speed range of urban conditions, engine operating in the medium-speed range of urban conditions, and engine operating in the high-speed range of urban conditions.

[0087] Step 204: Determine whether there is an actual fuel supply factor that meets the target conditions among the actual fuel supply factors under each engine operating condition.

[0088] In the embodiments of this application, if Figure 5 As shown, determining whether there exists an actual fuel supply factor that meets the target conditions among the actual fuel supply factors under each engine operating condition includes steps 2041-2045:

[0089] For any engine operating condition, execute step 2041 for the actual fuel supply factor.

[0090] Step 2041: Determine whether there is an actual fuel supply factor that is not within the range of the first fuel supply factor. If not, proceed to step 2042; if yes, proceed to step 2043.

[0091] The first fuel supply factor range is the range of the first fuel supply factor corresponding to the actual fuel supply factor under engine operating conditions. The range of the first fuel supply factor corresponding to the actual fuel supply factor is obtained by collecting the range of the first fuel supply factor at the time of the actual fuel supply factor.

[0092] In this embodiment of the application, any actual fuel supply factor is compared with the first fuel supply factor range to determine whether the actual fuel supply factor is within the first fuel supply range. If the actual fuel supply factor is not within the first fuel supply range, it is determined that there are actual fuel supply factors that are not within the first fuel supply factor range. If all actual fuel supply factors under any engine operating condition are within the first fuel supply range, it is determined that there are no actual fuel supply factors that are not within the first fuel supply factor range under that engine operating condition.

[0093] Step 2042: Determine that there is no actual fuel supply factor that meets the target conditions among the actual fuel supply factors under engine operating conditions.

[0094] In this embodiment, an actual fuel supply factor that does not meet the target condition is one that falls within both the first and second fuel supply factor ranges corresponding to the actual fuel supply factor. This indicates that the actual fuel supply factor is normal.

[0095] Step 2043: Determine whether the actual fuel supply factor that is not within the range of the first fuel supply factor is not within the range of the second fuel supply factor; if yes, proceed to step 2044; if no, proceed to step 2045.

[0096] In this embodiment of the application, if any actual fuel supply factor is not within the first fuel supply factor range corresponding to the actual fuel supply factor and is not within the second fuel supply factor range under the engine operating condition, then it is determined that there is an actual fuel supply factor that meets the target condition under the engine operating condition; if all actual fuel supply factors under the engine operating condition are within the first fuel supply factor range corresponding to the actual fuel supply factor and are within the second fuel supply factor range, then it is determined that there is no actual fuel supply factor that meets the target condition under the engine operating condition.

[0097] It should be noted that when there is an actual fuel supply factor that is not within the range of the first fuel supply factor, as long as it is determined whether the actual fuel supply factor that is not within the range of the first fuel supply factor is within the range of the second fuel supply factor, it can be determined whether there is an actual fuel supply factor that meets the target conditions among the actual fuel supply factors under the engine operating conditions.

[0098] Step 2044: Determine whether there is an actual fuel supply factor that meets the target conditions among the actual fuel supply factors under each engine operating condition.

[0099] Step 2045: Determine that there is no actual fuel supply factor that meets the target conditions among the actual fuel supply factors under each engine operating condition.

[0100] Step 205: If there is an actual fuel supply factor that meets the target condition among all actual fuel supply factors under all engine operating conditions, determine that multiple actual fuel supply factors meet the fault condition. If multiple actual fuel supply factors meet the fault condition, proceed to step 207.

[0101] Step 206: If no actual fuel supply factor meets the target conditions under any engine operating condition, determine that multiple actual fuel supply factors do not meet the fault conditions. If multiple actual fuel supply factors do not meet the fault conditions, proceed to step 209.

[0102] Step 207: Determine if there is an engine malfunction. If there is an engine malfunction, proceed to step 208.

[0103] Step 208: Adjust the actual fuel injection quantity of the vehicle engine using the currently obtained actual fuel injection factor from multiple actual fuel injection factors.

[0104] In this embodiment, when an engine malfunction is determined, it indicates that the currently obtained actual fuel injection factor is inaccurate. To prevent the deviation between the actual air-fuel ratio and the stoichiometric air-fuel ratio from becoming increasingly larger, a new actual fuel injection factor is not calculated. Instead, the actual fuel injection quantity of the vehicle engine is adjusted based on the currently obtained actual fuel injection factor until the engine malfunction is repaired. The specific malfunction of the engine can be subsequently determined through manual diagnosis.

[0105] Step 209: Confirm that there is no engine malfunction.

[0106] In this embodiment, multiple actual fuel injection factors for adjusting the actual fuel injection quantity of a vehicle engine are acquired in real time at preset time intervals within a preset time period. The presence of different actual fuel injection factors under different engine operating conditions is determined by judging whether these factors fall within the range of a first fuel injection factor corresponding to the engine operating condition, and whether the different fuel injection factors fall within the range of a preset second fuel injection factor used to ensure that vehicle exhaust emissions do not exceed emission limits. This process determines whether an engine malfunction exists. In this embodiment, determining engine malfunction by applying multiple conditional judgments to the actual fuel injection factors under different engine operating conditions makes engine fault diagnosis more accurate.

[0107] Figure 6 This is a schematic diagram of the structure of an engine diagnostic device provided in an embodiment of this application. The engine diagnostic device can be implemented by software, hardware, or a combination of both. The engine diagnostic device may include: an acquisition module 601, a determination module 602, a first determination module 603, a second determination module 604, and a third determination module 605.

[0108] The acquisition module 601 is used to acquire multiple actual fuel supply factors in real time within a preset time period according to a preset time interval. The actual fuel supply factors are used to adjust the actual fuel injection quantity of the vehicle engine.

[0109] The determining module 602 is used to determine the first fuel supply factor range corresponding to each actual fuel supply factor and obtain the preset second fuel supply factor range for each actual fuel supply factor among multiple actual fuel supply factors; the first fuel supply factor range is the fuel supply factor range under the engine operating conditions corresponding to the actual fuel supply factor, and the second fuel supply factor range is the fuel supply factor range that ensures the vehicle's exhaust emissions do not exceed the emission limits.

[0110] The first determination module 603 is used to determine whether multiple actual fuel supply factors meet the fault conditions based on the first fuel supply factor range and the second fuel supply factor range corresponding to each actual fuel supply factor. Each actual fuel supply factor corresponds to an engine operating condition. The fault condition is that the multiple actual fuel supply factors include multiple actual fuel supply factors under different engine operating conditions, and the multiple actual fuel supply factors under different engine operating conditions meet the target condition. The target condition is that there exists an actual fuel supply factor under each engine operating condition that is not located in the first fuel supply factor range corresponding to the actual fuel supply factor and is not located in the second fuel supply factor range.

[0111] The second determination module 604 is used to determine that the engine has a fault if multiple actual fuel supply factors meet the fault conditions.

[0112] The third determination module 605 is used to determine that the engine does not have a fault if multiple actual fuel supply factors do not meet the fault conditions.

[0113] Optionally, the first determination module 603 includes:

[0114] The judgment submodule is used to determine whether the multiple actual fuel supply factors include multiple actual fuel supply factors under different engine operating conditions. If so, it determines whether there is an actual fuel supply factor that meets the target conditions among the actual fuel supply factors under each engine operating condition.

[0115] The first determination submodule is used to determine that multiple actual fuel supply factors meet the fault conditions if there are actual fuel supply factors that meet the target conditions among the actual fuel supply factors under all engine operating conditions.

[0116] The second determination submodule is used to determine that multiple actual fuel supply factors do not meet the fault conditions if no actual fuel supply factor meets the target conditions under any engine operating condition.

[0117] Optionally, the first determination submodule is used for:

[0118] For any engine operating condition, determine whether there is an actual fuel supply factor that is not within the range of the first fuel supply factor.

[0119] If not, it is determined that there is no actual fuel supply factor that meets the target condition among the actual fuel supply factors under the engine operating conditions; if so, it is determined whether the actual fuel supply factor that is not in the range of the first fuel supply factor is not in the range of the second fuel supply factor.

[0120] If yes, it is determined that there is an actual fuel supply factor that meets the target condition among the actual fuel supply factors under the engine operating conditions; otherwise, it is determined that there is no actual fuel supply factor that meets the target condition among the actual fuel supply factors under the engine operating conditions.

[0121] Optionally, module 602 includes:

[0122] The acquisition submodule is used to acquire the engine load rate and engine speed corresponding to the actual fuel supply factor;

[0123] The determination submodule is used to determine the range of the first fuel supply factor based on the engine load rate and engine speed.

[0124] Optionally, the device further includes:

[0125] The adjustment module is used to adjust the actual fuel injection quantity of the vehicle engine by using the latest actual fuel injection factor among multiple actual fuel injection factors when the engine malfunctions.

[0126] In this embodiment, multiple actual fuel injection factors for adjusting the actual fuel injection quantity of a vehicle engine are acquired in real time at preset time intervals within a preset time period. The presence of different actual fuel injection factors under different engine operating conditions is determined by judging whether these factors fall within the range of a first fuel injection factor corresponding to the engine operating condition and whether they fall within the range of a preset second fuel injection factor used to ensure that vehicle exhaust emissions do not exceed emission limits. This method of determining engine malfunction through multiple conditional judgments on the actual fuel injection factors under different engine operating conditions makes engine fault diagnosis more accurate.

[0127] It should be noted that the engine diagnostic device provided in the above embodiments is only illustrated by the division of the functional modules described above. In practical applications, the functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. Furthermore, the engine diagnostic device and the engine diagnostic method embodiments provided in the above embodiments belong to the same concept, and their specific implementation process can be found in the method embodiments, which will not be repeated here.

[0128] This application also provides a non-transitory computer-readable storage medium storing instructions that, when executed by a processor, implement any step in the above-described engine diagnostic method.

[0129] This application also provides a computer program product containing instructions that, when run on a computer, causes the computer to perform any step in the above-described engine diagnostic method.

[0130] Those skilled in the art will understand that all or part of the steps of the above embodiments can be implemented by hardware or by a program instructing related hardware. The program can be stored in a computer-readable storage medium, such as a read-only memory, a disk, or an optical disk.

[0131] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present application should be included within the protection scope of the present application.

Claims

1. A method for diagnosing an engine, characterized in that, The method includes: Multiple actual fuel supply factors are acquired in real time at preset time intervals within a preset time period. The actual fuel supply factors are used to adjust the actual fuel injection quantity of the vehicle engine. For each of the plurality of actual fuel supply factors, a first fuel supply factor range corresponding to each actual fuel supply factor is determined and a preset second fuel supply factor range is obtained; the first fuel supply factor range is the fuel supply factor range under the engine operating conditions corresponding to the actual fuel supply factor, and the second fuel supply factor range is the fuel supply factor range that ensures the vehicle's exhaust emissions do not exceed the emission limits. Based on the first fuel supply factor range and the second fuel supply factor range corresponding to each actual fuel supply factor, it is determined whether the plurality of actual fuel supply factors meet the fault conditions. Each actual fuel supply factor corresponds to an engine operating condition. The fault conditions are: the plurality of actual fuel supply factors include multiple actual fuel supply factors under different engine operating conditions, and the multiple actual fuel supply factors under different engine operating conditions meet the target conditions. The target conditions are that at least one actual fuel supply factor under each engine operating condition is not located in the first fuel supply factor range corresponding to the actual fuel supply factor and is not located in the second fuel supply factor range. If the multiple actual fuel supply factors meet the fault conditions, then the engine is determined to be faulty; If the multiple actual fuel supply factors do not meet the fault conditions, then it is determined that the engine does not have a fault.

2. The method as described in claim 1, characterized in that, The determination of whether the plurality of actual fuel supply factors meet the fault conditions includes: Determine whether the plurality of actual fuel supply factors include multiple actual fuel supply factors under different engine operating conditions. If so, determine whether there is an actual fuel supply factor that satisfies the target condition among the actual fuel supply factors under each engine operating condition. If there is an actual fuel supply factor that meets the target condition among all the actual fuel supply factors under all engine operating conditions, then it is determined that the multiple actual fuel supply factors meet the fault condition. If no actual fuel supply factor meets the target condition under any engine operating condition, then the plurality of actual fuel supply factors are determined not to meet the fault condition.

3. The method as described in claim 2, characterized in that, The determination of whether there exists an actual fuel supply factor that satisfies the target condition among the actual fuel supply factors under each engine operating condition includes: For any engine operating condition, determine whether there is an actual fuel supply factor that is not within the range of the first fuel supply factor. If not, it is determined that there is no actual fuel supply factor that meets the target condition among the actual fuel supply factors under the engine operating conditions; if yes, it is determined whether the actual fuel supply factor that is not in the range of the first fuel supply factor is not in the range of the second fuel supply factor. If yes, it is determined that there is an actual fuel supply factor that satisfies the target condition among the actual fuel supply factors under the engine operating conditions; otherwise, it is determined that there is no actual fuel supply factor that satisfies the target condition among the actual fuel supply factors under the engine operating conditions.

4. The method as described in claim 1, characterized in that, Determining the first fuel supply factor range corresponding to the actual fuel supply factor includes: Obtain the engine load rate corresponding to the actual fuel supply factor and the engine speed corresponding to the actual fuel supply factor; The range of the first fuel supply factor is determined based on the engine load rate and the engine speed.

5. The method as described in claim 1, characterized in that, The method further includes: When the engine malfunctions, the actual fuel injection quantity of the vehicle engine is adjusted using the latest actual fuel injection factor among the plurality of actual fuel injection factors.

6. A diagnostic device for an engine, characterized in that, The device includes: The acquisition module is used to acquire multiple actual fuel supply factors in real time at preset time intervals within a preset time period. The actual fuel supply factors are used to adjust the actual fuel injection quantity of the vehicle engine. The determining module is used to determine a first fuel supply factor range and obtain a preset second fuel supply factor range for each of the plurality of actual fuel supply factors; the first fuel supply factor range is the fuel supply factor range under the engine operating conditions corresponding to the actual fuel supply factor, and the second fuel supply factor range is the fuel supply factor range that ensures the vehicle's exhaust emissions do not exceed the emission limits. The first determination module is used to determine whether the plurality of actual fuel supply factors meet the fault conditions based on the first fuel supply factor range and the second fuel supply factor range corresponding to each actual fuel supply factor. Each actual fuel supply factor corresponds to an engine operating condition. The fault condition is that the plurality of actual fuel supply factors include multiple actual fuel supply factors under different engine operating conditions, and the multiple actual fuel supply factors under different engine operating conditions meet the target condition. The target condition is that there exists at least one actual fuel supply factor under each engine operating condition that is not located in the first fuel supply factor range corresponding to the actual fuel supply factor and is not located in the second fuel supply factor range. The second determination module is used to determine that the engine has a fault if the plurality of actual fuel supply factors meet the fault conditions. The third determination module is used to determine that the engine does not have a fault if the plurality of actual fuel supply factors do not meet the fault conditions.

7. The apparatus as claimed in claim 6, characterized in that, The first determination module includes: The judgment submodule is used to determine whether the multiple actual fuel supply factors include multiple actual fuel supply factors under different engine operating conditions. If so, it is determined whether there is an actual fuel supply factor that meets the target condition among the actual fuel supply factors under each engine operating condition. The first determination submodule is used to determine that if there is an actual fuel supply factor that satisfies the target condition among the actual fuel supply factors under all engine operating conditions, then the plurality of actual fuel supply factors satisfy the fault condition. The second determination submodule is used to determine that if no actual fuel supply factor meets the target condition under any engine operating condition, the plurality of actual fuel supply factors do not meet the fault condition.

8. The apparatus as claimed in claim 7, characterized in that, The first determination submodule is used for: For any engine operating condition, determine whether there is an actual fuel supply factor that is not within the range of the first fuel supply factor. If not, it is determined that there is no actual fuel supply factor that meets the target condition among the actual fuel supply factors under the engine operating conditions; If so, then determine whether the actual fuel supply factor that is not within the range of the first fuel supply factor is not within the range of the second fuel supply factor; If yes, it is determined that there is an actual fuel supply factor that satisfies the target condition among the actual fuel supply factors under the engine operating conditions; otherwise, it is determined that there is no actual fuel supply factor that satisfies the target condition among the actual fuel supply factors under the engine operating conditions.

9. The apparatus as claimed in claim 6, characterized in that, The determining module includes: The acquisition submodule is used to acquire the engine load rate corresponding to the actual fuel supply factor and the engine speed corresponding to the actual fuel supply factor. A determination submodule is used to determine the range of the first fuel supply factor based on the engine load rate and the engine speed.

10. A computer-readable storage medium storing instructions that, when executed by a processor, implement the diagnostic method for an engine according to any one of claims 1-5.

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