Method and device for determining misfire threshold, misfire diagnosis method and computer equipment

Abstract

The present invention discloses a method and device for determining a misfire threshold, a misfire diagnosis method and a computer device. The method for determining a misfire threshold comprises: obtaining characteristic data at a calculation point corresponding to each cylinder of a gasoline engine; when performing a misfire judgment on a cylinder at each calculation point, determining the calculation point at which the cylinder load corresponding to the cylinder is collected as the first calculation point, and determining the calculation point at which the cylinder speed corresponding to the cylinder is collected as the second calculation point; both the first calculation point and the second calculation point are calculation points that are advanced relative to the calculation point at which the misfire judgment on the cylinder is performed; at the calculation point at which the misfire judgment on the cylinder is performed, the misfire threshold is determined according to the cylinder load at the first calculation point and the cylinder speed at the second calculation point. The technical solution provided in the embodiment of the present invention can achieve a misfire threshold that is synchronized in time with the misfire characteristic value when performing a misfire judgment, thereby improving the accuracy of the misfire judgment of the vehicle.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of automobile technology, and in particular to a method and device for determining a misfire threshold, a misfire diagnosis method, and a computer device. Background Art

[0002] A gasoline engine cylinder misfire can increase vehicle emissions or even damage the vehicle, so the gasoline engine control system needs to be able to detect misfire faults under almost all positive torque conditions. It is very difficult to accurately detect misfires under all operating conditions.

[0003] The current mainstream misfire diagnosis method is to directly use the gasoline engine cylinder data collected at the time of diagnosis to perform misfire diagnosis. However, in transient conditions and idling conditions where the vehicle cylinder data changes, there will be inaccurate misfire diagnosis. How to improve the accuracy of misfire judgment under transient and idling conditions of the vehicle has become an urgent problem to be solved. Summary of the invention

[0004] The present invention provides a method and device for determining a misfire threshold, a misfire diagnosis method and a computer device to solve the problem of asynchrony between the misfire threshold and misfire characteristic data, thereby improving the accuracy of misfire diagnosis under transient and idle conditions of the engine.

[0005] In a first aspect, an embodiment of the present invention provides a method for determining a misfire threshold, comprising:

[0006] Acquire characteristic data at a calculation point corresponding to each cylinder of the gasoline engine; wherein the gasoline engine comprises a plurality of cylinders, and each cylinder corresponds to one calculation point in each working cycle; the characteristic data comprises cylinder load and cylinder speed;

[0007] When misfire judgment of the cylinder is performed at each of the calculation points, the calculation point at which the cylinder load corresponding to the cylinder is collected is determined as the first calculation point, and the calculation point at which the cylinder speed corresponding to the cylinder is collected is determined as the second calculation point; the first calculation point and the second calculation point are both calculation points that are advanced relative to the calculation point at which misfire judgment is performed on the cylinder;

[0008] At the calculation point for making a misfire judgment of the cylinder, the misfire threshold is determined based on the cylinder load at the first calculation point and the cylinder speed at the second calculation point.

[0009] Optionally, when performing misfire judgment on the cylinder for each calculation point, determining the calculation point at which the cylinder load corresponding to the cylinder is collected as the first calculation point, and determining the calculation point at which the cylinder speed corresponding to the cylinder is collected as the second calculation point includes:

[0010] When performing misfire judgment on the cylinder for each of the calculation points, determining the calculation point at which the cylinder load corresponding to the cylinder is collected as the first calculation point according to the load advance amount;

[0011] The calculation point of the cylinder speed corresponding to the cylinder is determined as the second calculation point according to the speed advance; the load advance and the speed advance are both advances relative to the calculation point for misfire judgment.

[0012] Optionally, the characteristic data also includes combustion characteristic data;

[0013] For each of the cylinders, the load advance amount includes at least the advance amount of the calculation point of the cylinder load corresponding to the cylinder relative to the calculation point of the combustion characteristic data; the speed advance amount includes at least the advance amount of the calculation point of the cylinder speed corresponding to the cylinder relative to the calculation point of the combustion characteristic data.

[0014] Optionally, when performing misfire judgment on the cylinder for each of the calculation points, the calculation point at which the combustion characteristic data corresponding to the cylinder is collected is determined to be a third calculation point; and the calculation point for performing misfire judgment is a calculation point delayed relative to the third calculation point.

[0015] Optionally, the load advance amount is equal to the sum of the advance amount of the calculation point where the cylinder load corresponding to the cylinder is collected relative to the calculation point where the combustion characteristic data is collected and the preset misfire algorithm delay amount;

[0016] The speed advance amount is equal to the sum of the advance amount of the calculation point where the cylinder speed corresponding to the cylinder is collected relative to the calculation point where the combustion characteristic data is collected and the preset misfire algorithm delay amount.

[0017] In a second aspect, an embodiment of the present invention further provides a misfire diagnosis method, comprising:

[0018] Determine a misfire threshold; wherein the misfire threshold is determined using the method for determining the misfire threshold described in the first aspect;

[0019] Determine the misfire characteristic value based on the combustion characteristic data of n calculation points before and after the calculation point where the combustion characteristic data of the cylinder is obtained; wherein n is equal to the preset misfire algorithm delay amount;

[0020] At a calculation point for misfire judgment of the cylinder, a misfire result of the cylinder is determined according to a misfire threshold and a misfire characteristic value.

[0021] Optionally, at the calculation point for misfire judgment of the cylinder, determining the misfire result of the cylinder according to the misfire threshold and the misfire characteristic value includes:

[0022] If the misfire characteristic value exceeds the misfire threshold, determining that the cylinder is misfiring;

[0023] If the misfire characteristic value does not exceed the misfire threshold, it is determined that the cylinder is normal.

[0024] In a third aspect, an embodiment of the present invention further provides a device for determining a misfire threshold, comprising:

[0025] An acquisition module, used for acquiring characteristic data at a calculation point corresponding to each cylinder of the gasoline engine; wherein the gasoline engine comprises a plurality of cylinders, and each cylinder corresponds to one calculation point in each working cycle; and the characteristic data comprises cylinder load and cylinder speed;

[0026] a first determination module, for determining the calculation point at which the cylinder load corresponding to the cylinder is collected as the first calculation point, and determining the calculation point at which the cylinder speed corresponding to the cylinder is collected as the second calculation point when performing misfire judgment on the cylinder at each calculation point; the first calculation point and the second calculation point are both calculation points that are ahead of the calculation point at which misfire judgment is performed on the cylinder;

[0027] The second determination module is used to determine the misfire threshold value at the calculation point for determining the misfire of the cylinder according to the cylinder load at the first calculation point and the cylinder speed at the second calculation point.

[0028] In a fourth aspect, an embodiment of the present invention further provides a computer device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method described in the first aspect and the second aspect is implemented.

[0029] In a fifth aspect, an embodiment of the present invention further provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method described in the first and second aspects of the present invention.

[0030] The technical solution provided by the embodiment of the present invention is that when calculating the misfire threshold of the gasoline engine cylinder for misfire diagnosis, the characteristic data used in the cylinder misfire threshold calculation is set with an algorithm delay relative to the time of misfire diagnosis, and a corresponding advance amount is set when acquiring the characteristic data. The cylinder load corresponding to the cylinder is first acquired, and then the cylinder speed corresponding to the cylinder is acquired, and then the misfire threshold of the cylinder is determined based on the acquired cylinder load and cylinder speed corresponding to the cylinder. The calculated cylinder misfire threshold can be synchronized with the misfire characteristic data in time, and the accuracy of misfire diagnosis under transient and idle conditions of the engine is improved when misfire diagnosis is performed on the cylinder later. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1A flowchart of a method for determining a misfire threshold provided in Embodiment 1 of the present invention;

[0032] Figure 2 A flowchart of another method for determining a misfire threshold provided in Embodiment 2 of the present invention;

[0033] Figure 3 A misfire detection timing diagram provided in Embodiment 2 of the present invention;

[0034] Figure 4 A flow chart of a misfire diagnosis method provided in Embodiment 3 of the present invention;

[0035] Figure 5 A schematic diagram of the structure of a device for determining a misfire threshold value provided in a fourth embodiment of the present invention;

[0036] Figure 6 A schematic diagram of the structure of a computer device provided in Embodiment 5 of the present invention. DETAILED DESCRIPTION

[0037] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0038] Embodiment 1

[0039] Figure 1 This is a flow chart of a method for determining a misfire threshold provided in the first embodiment of the present invention. This embodiment is applicable to the case of misfire diagnosis of a cylinder of a four-stroke gasoline engine. The method can be executed by a misfire threshold determination device, which can be implemented in software and / or hardware and integrated in a computer device, such as Figure 1 As shown, the method specifically comprises the following steps:

[0040] S110, acquiring characteristic data at a calculation point corresponding to each cylinder of the gasoline engine.

[0041] Among them, the gasoline engine includes multiple cylinders, and each cylinder corresponds to a calculation point in each working cycle; the characteristic data includes cylinder load and cylinder speed. The gasoline engine can be a four-stroke gasoline engine including an intake stroke, a compression stroke, a power stroke and an exhaust stroke in one working cycle. The number of cylinders of the gasoline engine can be four cylinders or six cylinders or other cylinder numbers. Taking a four-cylinder gasoline engine as an example, when the gasoline engine cylinders are running, the four cylinders are in four different strokes at each moment. For any cylinder, the calculation point in one working cycle can be a moment or a period in any stroke. For example, the calculation point in one working cycle is a moment or a period in the intake stroke at the calculation point of each cylinder, and the cylinder characteristic data can be obtained. However, since the gasoline engine is a four-stroke internal combustion engine, the electronic control system calculates the injection amount based on the intake volume. When the engine is actually working, the injection always starts before the intake ends, so the electronic control system needs to estimate the intake volume in advance. For a 4-cylinder direct injection gasoline engine, the advance amount may reach 2~3 cylinders, and for a 6-cylinder direct injection gasoline engine, the advance amount may reach 3~4 cylinders. For a gasoline engine with intake port injection, the injection advance amount is more. Therefore, for the calculation point corresponding to any cylinder, the acquired characteristic data may not completely correspond to the cylinder, but also include the characteristic data corresponding to other cylinders. Correspondingly, the calculation point within the working cycle of a cylinder obtains the misfire threshold of other cylinders. Through the cycle, the misfire threshold of different cylinders can be determined at each calculation point of the gasoline engine. The acquired characteristic data may include the cylinder load and cylinder speed corresponding to the cylinder at the time of collection. The cylinder load and cylinder speed are data used to measure the cylinder operating point. The cylinder operating point can be defined in many ways, such as intake manifold pressure and speed, intake flow and speed, intake volume and speed per cylinder, fuel injection amount and time required for the crankshaft to make one revolution, etc. Under different circumstances, the physical quantities represented by the cylinder load and cylinder speed can be adaptively changed. This embodiment does not make any specific limitation on the cylinder load and cylinder speed.

[0042] S120. When misfire judgment is performed on a cylinder at each calculation point, the calculation point at which the cylinder load corresponding to the cylinder is collected is determined as the first calculation point, and the calculation point at which the cylinder speed corresponding to the cylinder is collected is determined as the second calculation point; both the first calculation point and the second calculation point are calculation points that are advanced relative to the calculation point at which misfire judgment is performed on the cylinder.

[0043] Among them, each calculation point corresponds to the moment of misfire judgment for a cylinder. The moment of obtaining the characteristic data corresponding to the cylinder is not obtained at the moment of the calculation point of the cylinder. The calculation point corresponding to the cylinder load for obtaining the cylinder is the first calculation point, and the first calculation point is a calculation point that is advanced relative to the calculation point for misfire judgment of the cylinder. The calculation point corresponding to the cylinder speed for obtaining the cylinder is the second calculation point, and the second calculation point is also a calculation point that is advanced relative to the calculation point for misfire judgment of the cylinder. In this way, at the calculation point of the moment of misfire judgment for any cylinder, it is easier to obtain the cylinder load and cylinder speed corresponding to the cylinder. Compared with the method of directly using the cylinder load and cylinder speed collected at the moment of misfire diagnosis to perform misfire diagnosis in the prior art, the characteristic data is less likely to have deviations, which can improve the accuracy of misfire diagnosis.

[0044] S130. At a calculation point for determining misfire of a cylinder, determine a misfire threshold value according to a cylinder load at a first calculation point and a cylinder speed at a second calculation point.

[0045] This step is applicable to any cylinder of the gasoline engine. Exemplarily, the cylinders of the gasoline engine include the first cylinder, the second cylinder, the third cylinder and the fourth cylinder. At the calculation point for misfire judgment of the first cylinder, the misfire threshold is determined according to the cylinder load at the first calculation point corresponding to the first cylinder and the cylinder speed at the second calculation point corresponding to the first cylinder. At the calculation point for misfire judgment of the second cylinder, the third cylinder and the fourth cylinder, the misfire threshold of the second cylinder is determined similarly to the above case, which will not be described in detail.

[0046] Among them, at the calculation point for misfire judgment of the cylinder, misfire judgment can be made according to the characteristic data corresponding to the cylinder. Specifically, the cylinder load corresponding to the cylinder obtained at the first calculation point and the cylinder speed corresponding to the cylinder obtained at the second calculation point can be used to determine the misfire threshold of the cylinder. The transient operating condition of a gasoline engine is a process in which the speed and load are constantly changing. If the misfire judgment is made directly according to the characteristic data collected at the calculation point, there will be a large difference in time between the misfire threshold and the misfire characteristic data, which will affect the misfire judgment result and driving safety. Obtaining the characteristic data corresponding to the cylinder at a calculation point ahead of the misfire judgment calculation point can reduce the time difference between the cylinder misfire threshold and the misfire characteristic under transient and idle conditions of the gasoline engine, maintain the time synchronization between the cylinder misfire threshold and the misfire characteristic, and thus improve the accuracy of the cylinder misfire judgment.

[0047] The technical solution provided by the embodiment of the present invention is that when calculating the misfire threshold of the gasoline engine cylinder for misfire diagnosis, the characteristic data used in the cylinder misfire threshold calculation is set with an algorithm delay relative to the time of misfire diagnosis, and a corresponding advance amount is set when acquiring the characteristic data. The cylinder load corresponding to the cylinder is first acquired, and then the cylinder speed corresponding to the cylinder is acquired, and then the misfire threshold of the cylinder is determined based on the acquired cylinder load and cylinder speed corresponding to the cylinder. The calculated cylinder misfire threshold can be synchronized with the misfire characteristic data in time, and the accuracy of misfire diagnosis under transient and idle conditions of the engine is improved when misfire diagnosis is performed on the cylinder later.

[0048] Embodiment 2

[0049] Figure 2 A flowchart of another method for determining a misfire threshold provided in the second embodiment of the present invention. Figure 3 A fire detection timing diagram provided in the second embodiment of the present invention. Figure 2 and Figure 3 , the method specifically comprises the following steps:

[0050] S210, acquiring characteristic data at a calculation point corresponding to each cylinder of the gasoline engine.

[0051] S220. Determine the calculation point of the cylinder load corresponding to the cylinder as the first calculation point based on the load advance amount; determine the calculation point of the cylinder speed corresponding to the cylinder as the second calculation point based on the speed advance amount; both the load advance amount and the speed advance amount are advance amounts relative to the calculation point for misfire judgment.

[0052] When misfire is judged for each cylinder, the calculation point of the cylinder load corresponding to the cylinder is specifically determined by the load advance amount, i.e., the first calculation point; the calculation point of the cylinder speed corresponding to the cylinder is specifically determined by the speed advance amount, i.e., the second calculation point. For example, six moments are divided according to the crankshaft rotation angle, namely, the first moment CP1, the second moment CP2, the third moment CP3, the fourth moment CP4, the fifth moment CP5, and the sixth moment CP6. Figure 3 Taking cylinder 1 as an example, the calculation point for misfire judgment of cylinder 1 is at the sixth moment CP6, and the load advance corresponding to the cylinder is five, then the calculation point for obtaining the cylinder load corresponding to the cylinder is at the first moment CP1, that is, the first calculation point is at the first moment CP1; the speed advance corresponding to the cylinder is three, then the calculation point for obtaining the cylinder speed corresponding to the cylinder is at the third moment CP3, that is, the second calculation point is at the third moment CP3. It should be noted that the load advance and speed advance are determined according to the specific misfire diagnosis algorithm, and this embodiment does not make a specific limitation on the load advance and speed advance.

[0053] S230, the characteristic data also includes combustion characteristic data; for each cylinder, the load advance amount at least includes the advance amount of the calculation point of the cylinder load corresponding to the cylinder relative to the calculation point of the combustion characteristic data; the speed advance amount at least includes the advance amount of the calculation point of the cylinder speed corresponding to the cylinder relative to the calculation point of the combustion characteristic data.

[0054] The combustion characteristic data may be the time required for the engine to rotate through a crankshaft angle interval, the average speed of the crankshaft during a crankshaft angle interval, the exhaust temperature, the air-fuel ratio, the cylinder pressure and other data that can evaluate the combustion conditions in the cylinder. The load advance amount at least includes the advance amount of the calculation point of the cylinder load corresponding to the cylinder relative to the calculation point of the combustion characteristic data, which means that in a cycle of misfire judgment for a cylinder, the moment of obtaining the calculation point of the cylinder load is advanced relative to the moment of obtaining the calculation point of the combustion characteristic data of the cylinder. The speed advance amount at least includes the advance amount of the calculation point of the cylinder speed corresponding to the cylinder relative to the calculation point of the combustion characteristic data, which means that the moment of obtaining the calculation point of the cylinder speed is also advanced relative to the moment of obtaining the calculation point of the combustion characteristic data of the cylinder.

[0055] S240, when performing misfire judgment on a cylinder for each calculation point, determine the calculation point at which the combustion characteristic data corresponding to the cylinder is collected as the third calculation point; and the calculation point for performing misfire judgment is a calculation point delayed relative to the third calculation point.

[0056] When misfire diagnosis is performed on a cylinder, the calculation point for obtaining the combustion characteristic data corresponding to the cylinder, i.e., the third calculation point, is specifically determined by presetting the misfire algorithm delay amount. Figure 3 Take cylinder 1 as an example. The calculation point for misfire judgment of cylinder 1 is at the sixth moment CP6, and the preset misfire algorithm delay amount corresponding to the cylinder is two. Then the calculation point for obtaining combustion characteristic data of the cylinder is at the fourth moment CP4, that is, the third calculation point is at the fourth moment CP4.

[0057] S250, the load advance amount is equal to the sum of the advance amount of the calculation point of the cylinder load corresponding to the cylinder relative to the calculation point of the combustion characteristic data collected and the preset misfire algorithm delay amount; the speed advance amount is equal to the sum of the advance amount of the calculation point of the cylinder speed corresponding to the cylinder relative to the calculation point of the combustion characteristic data collected and the preset misfire algorithm delay amount.

[0058] When diagnosing misfire in a cylinder, the characteristic data that needs to be obtained include the cylinder load, cylinder speed and combustion characteristic data corresponding to the cylinder. Specifically, the time of obtaining the cylinder load calculation point is earlier than the time of obtaining the combustion characteristic data calculation point and the time of performing misfire diagnosis. Figure 3Taking cylinder 1 as an example, the calculation point for misfire diagnosis of cylinder 1 is the sixth moment CP6, and the preset misfire algorithm delay is two, so the calculation point for obtaining the combustion characteristic data corresponding to the cylinder is the fourth moment CP4. The advance amount of the calculation point for obtaining the cylinder load relative to the calculation point for obtaining the combustion characteristic data corresponding to the cylinder is three, so the moment for obtaining the cylinder load calculation point is the first calculation point, and the corresponding load advance amount is five. The advance amount of the calculation point for obtaining the cylinder speed relative to the calculation point for obtaining the combustion characteristic data corresponding to the cylinder is one, so the moment for obtaining the cylinder speed calculation point is the second calculation point, and the corresponding speed advance amount is three.

[0059] S260: At a calculation point for determining misfire of a cylinder, determine a misfire threshold value according to a cylinder load at a first calculation point and a cylinder speed at a second calculation point.

[0060] Embodiment 3

[0061] Figure 4 This is a flow chart of a misfire diagnosis method provided in the third embodiment of the present invention. This embodiment is applicable to the case of misfire diagnosis of a cylinder of a four-stroke gasoline engine. The method can be executed by a misfire threshold determination device, which can be implemented in software and / or hardware and integrated in a computer device. Based on the above embodiment, Figure 4 As shown, the method includes:

[0062] S401: Determine a fire threshold.

[0063] The misfire threshold is determined by the method for determining the misfire threshold in the first embodiment.

[0064] S402, determining a misfire characteristic value based on the combustion characteristic data of n calculation points before and after the calculation point where the combustion characteristic data of the cylinder is obtained; wherein n is equal to a preset misfire algorithm delay amount.

[0065] Among them, when calculating the misfire characteristic value corresponding to a cylinder, it is necessary to obtain the combustion data of multiple cylinders. Specifically, it is necessary to obtain the combustion characteristic data of the cylinder for misfire diagnosis corresponding to the third calculation point, and obtain the combustion characteristic data of n calculation points before and after the third calculation point, where n is equal to the preset misfire algorithm delay amount. Exemplarily, the preset misfire algorithm delay amount is two, and the misfire diagnosis calculation point corresponding to the cylinder is at the sixth moment, then the combustion characteristic data calculation point corresponding to the cylinder is at the fourth moment, and the moments of the two calculation points before and after it are the second moment, the third moment, the fifth moment and the sixth moment respectively. The misfire characteristic value corresponding to the cylinder is determined based on the combustion data of the calculation points obtained at the five moments from the second moment to the sixth moment. The preset misfire algorithm delay amount is determined according to the specific misfire detection algorithm, and the present embodiment does not specifically limit the preset misfire algorithm delay amount.

[0066] S403: At the calculation point for misfire judgment of the cylinder, determine the misfire result of the cylinder of the gasoline engine according to the misfire threshold and the misfire characteristic value.

[0067] Among them, at the calculation point for misfire judgment corresponding to the cylinder, misfire judgment can be performed on the cylinder according to the misfire characteristic value corresponding to the cylinder and the misfire threshold corresponding to the cylinder determined in the steps of the above embodiment. By setting a delay algorithm for misfire judgment, the misfire threshold and the misfire characteristic value when the cylinder is judged to be misfired are synchronized in time, thereby improving the accuracy of the misfire judgment on the cylinder.

[0068] On the basis of the above embodiment, optionally, at the calculation point for misfire judgment of the cylinder, the misfire result of the cylinder is determined according to the misfire threshold and the misfire characteristic value, including: if the misfire characteristic value exceeds the misfire threshold, it is determined that the cylinder is misfired; if the misfire characteristic value does not exceed the misfire threshold, it is determined that the cylinder is normal.

[0069] When specifically judging the misfire condition of a cylinder, the misfire characteristic value corresponding to the cylinder is compared with the misfire threshold value to judge the specific misfire condition. For example, if the misfire threshold value determined at the calculation point for misfire judgment of the cylinder is 10 and the determined misfire characteristic value is 11, it can be determined that the cylinder has misfired; if the misfire threshold value determined at the calculation point for misfire judgment of the cylinder is 10 and the determined misfire characteristic value is 9, it can be determined that the cylinder has not misfired and the cylinder state is normal.

[0070] The technical solution provided by the embodiment of the present invention is that when calculating the misfire threshold of the cylinder of a gasoline engine for misfire diagnosis, the characteristic data used in the calculation of the cylinder misfire threshold is set with an algorithm delay relative to the time of misfire diagnosis, and a corresponding advance amount is set when acquiring the characteristic data. First, the cylinder load corresponding to the cylinder is acquired, and then the cylinder speed corresponding to the cylinder is acquired, and then the misfire threshold of the cylinder is determined according to the acquired cylinder load and cylinder speed corresponding to the cylinder. And according to the preset misfire algorithm delay amount, the misfire characteristic value of the cylinder is determined by acquiring the combustion characteristic data of multiple calculation points corresponding to the preset number of misfire algorithm delay values ​​before and after the combustion characteristic data corresponding to the cylinder. The calculated cylinder misfire threshold can be synchronized with the misfire characteristic data in time, and when misfire diagnosis is performed on the cylinder, the accuracy of misfire diagnosis under transient and idle conditions of the engine is improved.

[0071] Embodiment 4

[0072] Figure 5 This is a schematic diagram of the structure of a misfire threshold determination device provided in the fourth embodiment of the present invention. The device can be implemented in hardware and / or software, and can generally be integrated into a computer device to execute the misfire diagnosis method provided in any embodiment of the present invention. Figure 5As shown, the misfire threshold determination device 500 includes:

[0073] The acquisition module 501 is used to acquire characteristic data at a calculation point corresponding to each cylinder of the gasoline engine; wherein the gasoline engine includes multiple cylinders, and each cylinder corresponds to a calculation point in each working cycle; the characteristic data includes cylinder load and cylinder speed.

[0074] The first determination module 502 is used to determine the calculation point where the cylinder load corresponding to the cylinder is collected as the first calculation point, and to determine the calculation point where the cylinder speed corresponding to the cylinder is collected as the second calculation point when performing cylinder misfire judgment at each calculation point; the first calculation point and the second calculation point are both calculation points that are ahead of the calculation point for performing cylinder misfire judgment.

[0075] The second determination module 503 is used to determine the misfire threshold value at the calculation point for misfire judgment of the cylinder according to the cylinder load at the first calculation point and the cylinder speed at the second calculation point.

[0076] On the basis of the above technical solution, optionally, the misfire threshold determination device further includes:

[0077] The third determination module is used to determine the misfire characteristic value according to the combustion characteristic data of n calculation points before and after the calculation point where the combustion characteristic data of the cylinder is obtained; wherein n is equal to the preset misfire algorithm delay amount.

[0078] On the basis of the above technical solution, optionally, the misfire threshold determination device further includes:

[0079] The judgment module is used to determine the misfire result of the cylinder of the gasoline engine according to the misfire threshold and the misfire characteristic value at the calculation point of the cylinder misfire judgment.

[0080] The misfire threshold determination device provided in the embodiment of the present invention can execute the misfire threshold determination method and misfire diagnosis method provided in any embodiment of the present invention, and has the corresponding functional modules and beneficial effects of the execution method, which will not be repeated here.

[0081] Embodiment 5

[0082] Figure 6 A schematic diagram of the structure of a computer device provided in Embodiment 5 of the present invention. Figure 6 A block diagram of an exemplary computer device 12 suitable for use in implementing embodiments of the present invention is shown. Figure 6 The computer device 12 shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present invention.

[0083] like Figure 6As shown, the computer device 12 is in the form of a general-purpose computing device. The components of the computer device 12 may include, but are not limited to: one or more processors or processing units 16, a system memory 28, and a bus 18 that connects various system components (including the system memory 28 and the processing unit 16).

[0084] Bus 18 represents one or more of several types of bus structures, including a memory bus or memory controller, a peripheral bus, an accelerated graphics port, a processor or a local bus using any of a variety of bus architectures. By way of example, these architectures include, but are not limited to, an Industry Standard Architecture (ISA) bus, a Micro Channel Architecture (MAC) bus, an Enhanced ISA bus, a Video Electronics Standards Association (VESA) local bus, and a Peripheral Component Interconnect (PCI) bus.

[0085] The computer device 12 typically includes a variety of computer system readable media. These media can be any available media that can be accessed by the computer device 12, including volatile and non-volatile media, removable and non-removable media.

[0086] The system memory 28 may include computer system readable media in the form of volatile memory, such as random access memory (RAM) 30 and / or cache memory 32. The computer device 12 may further include other removable / non-removable, volatile / non-volatile computer system storage media. By way of example only, the storage system 34 may be used to read and write non-removable, non-volatile magnetic media ( Figure 6 not shown, usually called a "hard drive"). Although Figure 6 Not shown in the figure, a disk drive for reading and writing to a removable non-volatile disk (e.g., a "floppy disk"), and an optical disk drive for reading and writing to a removable non-volatile optical disk (e.g., a CD-ROM, a DVD-ROM, or other optical media) may be provided. In these cases, each drive may be connected to the bus 18 via one or more data medium interfaces. The memory 28 may include at least one program product having a set (e.g., at least one) of program modules that are configured to perform the functions of the various embodiments of the present invention.

[0087] A program / utility 40 having a set (at least one) of program modules 42 may be stored, for example, in the memory 28, such program modules 42 including but not limited to an operating system, one or more application programs, other program modules, and program data, each of which or some combination may include an implementation of a network environment. The program modules 42 generally perform the functions and / or methods of the embodiments described herein.

[0088] The computer device 12 may also communicate with one or more external devices 14 (e.g., keyboards, pointing devices, displays 24, etc.), may communicate with one or more devices that enable a user to interact with the computer device 12, and / or may communicate with any device that enables the computer device 12 to communicate with one or more other computing devices (e.g., network cards, modems, etc.). This communication may be performed via an input / output (I / O) interface 22. In addition, the computer device 12 may also communicate with one or more networks (e.g., local area networks (LANs), wide area networks (WANs), and / or public networks, such as the Internet) via a network adapter 20. As shown, the network adapter 20 communicates with other modules of the computer device 12 via a bus 18. It should be understood that, although not shown in the figure, other hardware and / or software modules may be used in conjunction with the computer device 12, including but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage systems, etc.

[0089] The processing unit 16 executes various functional applications and data processing by running the programs stored in the system memory 28, such as implementing the human target detection method provided in the embodiment of the present invention.

[0090] Embodiment 6

[0091] Embodiment 6 of the present invention also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the various processes of the above-mentioned human target detection method are implemented, and the same technical effect can be achieved. To avoid repetition, it will not be repeated here.

[0092] Among them, computer-readable storage media may include, for example, but are not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or devices, or any combination of the above. More specific examples (non-exhaustive list) of computer-readable storage media include: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this document, a computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, device or device.

[0093] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A method for determining a misfire threshold, characterized in that: include: Acquire characteristic data at a calculation point corresponding to each cylinder of the gasoline engine; wherein the gasoline engine comprises a plurality of cylinders, and each cylinder corresponds to one calculation point in each working cycle; the characteristic data comprises cylinder load and cylinder speed; When misfire judgment of the cylinder is performed at each of the calculation points, the calculation point at which the cylinder load corresponding to the cylinder is collected is determined as the first calculation point, and the calculation point at which the cylinder speed corresponding to the cylinder is collected is determined as the second calculation point; the first calculation point and the second calculation point are both calculation points that are advanced relative to the calculation point at which misfire judgment is performed on the cylinder; At the calculation point for making a misfire judgment of the cylinder, the misfire threshold is determined based on the cylinder load at the first calculation point and the cylinder speed at the second calculation point.

2. The method for determining the misfire threshold according to claim 1, characterized in that: When performing misfire judgment on the cylinder for each calculation point, determining the calculation point where the cylinder load corresponding to the cylinder is collected as the first calculation point, and determining the calculation point where the cylinder speed corresponding to the cylinder is collected as the second calculation point, comprises: When performing misfire judgment on the cylinder for each of the calculation points, determining the calculation point at which the cylinder load corresponding to the cylinder is collected as the first calculation point according to the load advance amount; The calculation point of the cylinder speed corresponding to the cylinder is determined as the second calculation point according to the speed advance; the load advance and the speed advance are both advances relative to the calculation point for misfire judgment.

3. The method for determining the misfire threshold according to claim 2, characterized in that: The characteristic data also includes combustion characteristic data; For each of the cylinders, the load advance amount includes at least the advance amount of the calculation point of the cylinder load corresponding to the cylinder relative to the calculation point of the combustion characteristic data; the speed advance amount includes at least the advance amount of the calculation point of the cylinder speed corresponding to the cylinder relative to the calculation point of the combustion characteristic data.

4. The method for determining the misfire threshold according to claim 3, characterized in that: When performing misfire judgment on the cylinder for each of the calculation points, the calculation point at which the combustion characteristic data corresponding to the cylinder is collected is determined to be the third calculation point; and the calculation point for performing misfire judgment is a calculation point delayed relative to the third calculation point.

5. The method for determining the misfire threshold according to claim 4, characterized in that: The load advance amount is equal to the sum of the advance amount of the calculation point where the cylinder load corresponding to the cylinder is collected relative to the calculation point where the combustion characteristic data is collected and the preset misfire algorithm delay amount; The speed advance amount is equal to the sum of the advance amount of the calculation point where the cylinder speed corresponding to the cylinder is collected relative to the calculation point where the combustion characteristic data is collected and the preset misfire algorithm delay amount.

6. A method for diagnosing misfires, characterized in that: include: Determine a misfire threshold; wherein the misfire threshold is determined by the method for determining a misfire threshold according to any one of claims 1 to 5; Determine the misfire characteristic value based on the combustion characteristic data of n calculation points before and after the calculation point where the combustion characteristic data of the cylinder is obtained; wherein n is equal to the preset misfire algorithm delay amount; At a calculation point for misfire judgment of the cylinder, a misfire result of the cylinder is determined according to a misfire threshold and a misfire characteristic value.

7. The misfire diagnosis method according to claim 6, characterized in that: At a calculation point for misfire judgment of the cylinder, determining a misfire result of the cylinder according to a misfire threshold and a misfire characteristic value, including: If the misfire characteristic value exceeds the misfire threshold, determining that the cylinder is misfiring; If the misfire characteristic value does not exceed the misfire threshold, it is determined that the cylinder is normal.

8. A device for determining a misfire threshold, characterized in that: include: An acquisition module, used for acquiring characteristic data at a calculation point corresponding to each cylinder of the gasoline engine; wherein the gasoline engine comprises a plurality of cylinders, and each cylinder corresponds to one calculation point in each working cycle; and the characteristic data comprises cylinder load and cylinder speed; a first determination module, for determining the calculation point at which the cylinder load corresponding to the cylinder is collected as the first calculation point, and determining the calculation point at which the cylinder speed corresponding to the cylinder is collected as the second calculation point when performing misfire judgment on the cylinder at each calculation point; the first calculation point and the second calculation point are both calculation points that are ahead of the calculation point at which misfire judgment is performed on the cylinder; The second determination module is used to determine the misfire threshold value at the calculation point for determining the misfire of the cylinder according to the cylinder load at the first calculation point and the cylinder speed at the second calculation point.

9. A computer device comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method according to any one of claims 1 to 7 is implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.

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