A DPF fault diagnosis method, device, equipment and storage medium

Abstract

The application discloses a DPF fault diagnosis method, device, equipment and storage medium, and relates to the technical field of vehicles. The method comprises the following steps: acquiring an inlet measured temperature, an outlet measured temperature, a pipe wall temperature, an exhaust mass flow, an inner diameter and a shunt pipe length of a shunt pipe of a DPF; calculating an outlet simulated temperature of the shunt pipe through a formula, and calculating a temperature difference between the outlet measured temperature and the outlet simulated temperature; and if the temperature difference corresponding to multiple continuous calculation periods is all greater than a first preset difference threshold value, it is determined that the DPF has a fault. The method can improve the accuracy and efficiency of DPF fault diagnosis.

Description

Technical Field

[0001] This application relates to the field of computer technology, and in particular to a method, apparatus, device and storage medium for diagnosing DPF faults. Background Technology

[0002] Diesel particulate filters (DPFs) are a technology that can effectively reduce PM emissions from diesel vehicles. However, due to uncertainties related to fuel quality, lubricant quality, and road conditions, DPF systems are susceptible to damage from diesel engine operating conditions, ambient temperature, and the physicochemical properties of the fuel medium, leading to DPF malfunctions and various other problems.

[0003] Currently, fault diagnosis of DPFs requires extensive testing and experiments, and the establishment of DPF failure performance calibration models is achieved through manual calibration. This method is not only inefficient but also has poor accuracy. Summary of the Invention

[0004] This application provides a method, apparatus, device, and storage medium for diagnosing DPF faults, which can improve the accuracy and efficiency of DPF fault diagnosis.

[0005] To achieve the above objectives, this application adopts the following technical solution: Firstly, this application provides a method for diagnosing DPF faults, including: Obtain the inlet measurement temperature, outlet measurement temperature, pipe wall temperature, exhaust mass flow rate, inner diameter, and branch pipe length of the DPF's manifold; The simulated outlet temperature of the manifold is calculated using the following formula: in, The simulated outlet temperature. Measure the temperature at the inlet. The tube wall temperature is... Let d be the derivative of the exhaust mass flow rate with respect to time, d be the inner diameter, k be the convective heat transfer coefficient, and c be the coefficient of mass flow rate. p The specific heat is at constant pressure, and x is the length of the manifold. Calculate the temperature difference between the measured outlet temperature and the simulated outlet temperature; If the temperature difference corresponding to multiple consecutive calculation cycles is greater than the first preset difference threshold, then the DPF is determined to be faulty.

[0006] In some possible implementations, the method further includes: Obtain the first carbon load of the DPF, the environmental parameters of the vehicle, and the operating parameters of the vehicle. The calculation of the simulated outlet temperature of the shunt pipe includes: Calculate the simulated outlet temperature of the shunt pipe when the first carbon load of the DPF meets the first condition, the environmental parameters meet the second condition, and the operating condition parameters meet the third condition.

[0007] In some possible implementations, the first carbon loading of the DPF satisfies a first condition, including: The first carbon loading of the DPF is lower than a preset carbon loading threshold, and the rate of change of the first carbon loading of the DPF is lower than a preset carbon loading change rate threshold. The environmental parameters include ambient temperature and atmospheric pressure; the environmental parameters satisfy the second condition, including: The ambient temperature is within a first temperature range, the rate of change of the ambient temperature is lower than a preset ambient temperature change rate threshold, and the atmospheric pressure is within a first pressure range, the rate of change of the atmospheric pressure is lower than a preset atmospheric pressure change rate threshold. The operating parameters include the exhaust mass flow rate and the inlet measured temperature; the operating parameters satisfy a third condition, including: The exhaust mass flow rate is greater than a preset exhaust mass flow rate threshold, the inlet measured temperature is in the second temperature range, and the growth rate of the inlet measured temperature is greater than a preset growth rate threshold.

[0008] In some possible implementations, the method further includes: Obtain the second carbon loading deposited within a split-tube PM trap located upstream of the split-tube; If the difference between the second carbon load and the preset value is greater than the second preset difference, a prompt will be made to remove the carbon deposits in the PM collector of the diversion pipe.

[0009] In some possible implementations, the method further includes: The severity level corresponding to the temperature difference is determined based on a pre-defined correspondence between the reference temperature difference and the reference severity level.

[0010] Secondly, this application provides a diagnostic device for DPF faults, comprising: The acquisition module is used to acquire the inlet measurement temperature, outlet measurement temperature, pipe wall temperature, exhaust mass flow rate, inner diameter, and length of the DPF's manifold. The calculation module is used to calculate the simulated outlet temperature of the manifold using the following formula: in, The simulated outlet temperature. Measure the temperature at the inlet. The tube wall temperature is... Let d be the derivative of the exhaust mass flow rate with respect to time, d be the inner diameter, k be the convective heat transfer coefficient, and c be the coefficient of mass flow rate. p Let x be the specific heat at constant pressure and the length of the manifold; calculate the temperature difference between the measured outlet temperature and the simulated outlet temperature; The diagnostic module is used to determine that the DPF is faulty if the temperature difference corresponding to multiple consecutive calculation cycles is greater than a first preset difference threshold.

[0011] In some possible implementations, the acquisition module is further configured to acquire the first carbon load of the DPF, the environmental parameters of the vehicle, and the operating parameters of the vehicle; the calculation module is specifically configured to calculate the simulated outlet temperature of the shunt pipe when the first carbon load of the DPF satisfies a first condition, the environmental parameters satisfy a second condition, and the operating parameters satisfy a third condition.

[0012] In some possible implementations, the first carbon loading of the DPF satisfies a first condition, including: the first carbon loading of the DPF is lower than a preset carbon loading threshold, and the rate of change of the first carbon loading of the DPF is lower than a preset carbon loading change rate threshold; the environmental parameters include ambient temperature and atmospheric pressure; the environmental parameters satisfy a second condition, including: the ambient temperature is within a first temperature range, the rate of change of the ambient temperature is lower than a preset ambient temperature change rate threshold, the atmospheric pressure is within a first pressure range, and the rate of change of the atmospheric pressure is lower than a preset atmospheric pressure change rate threshold; the operating condition parameters include the exhaust mass flow rate and the inlet measured temperature; the operating condition parameters satisfy a third condition, including: the exhaust mass flow rate is greater than a preset exhaust mass flow rate threshold, the inlet measured temperature is within a second temperature range, and the rate of increase of the inlet measured temperature is greater than a preset rate of increase threshold.

[0013] In some possible implementations, the device further includes a prompting module; the acquisition module is further configured to acquire a second carbon load deposited in the split-tube PM trap, the split-tube PM trap being located upstream of the split-tube; the prompting module is configured to prompt the removal of carbon deposits from the split-tube PM trap if the difference between the second carbon load and a preset value is greater than a second preset difference.

[0014] In some possible implementations, the device further includes a determining module, which is used to determine the severity corresponding to the temperature difference based on a pre-set correspondence between a reference temperature difference and a reference severity.

[0015] Thirdly, this application provides a computing device, including a memory and a processor; The memory stores one or more computer programs, the one or more computer programs including instructions; when the instructions are executed by the processor, the computing device performs the method as described in any one of the first aspects.

[0016] Fourthly, this application provides a computer-readable storage medium for storing a computer program for performing the method as described in any one of the first aspects.

[0017] As can be seen from the above technical solution, this application has at least the following beneficial effects: This application provides a method for diagnosing DPF (Device Filter) faults. The method includes first obtaining the inlet measured temperature, outlet measured temperature, pipe wall temperature, exhaust mass flow rate, inner diameter, and branch pipe length of the DPF's manifold, and then calculating the simulated outlet temperature of the manifold using the following formula: in, The simulated outlet temperature. Measure the temperature at the inlet. The tube wall temperature is... Let d be the derivative of the exhaust mass flow rate with respect to time, d be the inner diameter, k be the convective heat transfer coefficient, and c be the coefficient of mass flow rate. p The specific heat is at constant pressure, and x is the length of the manifold. Next, the temperature difference between the measured outlet temperature and the simulated outlet temperature is calculated. If the temperature difference for multiple consecutive calculation cycles is greater than a first preset threshold, the DPF is determined to be faulty. This method improves diagnostic efficiency by comparing the simulated and measured temperatures at the shunt outlet. Furthermore, by using multiple diagnostic checks where the temperature difference exceeds the first preset threshold, the method increases the fault tolerance rate and thus improves diagnostic accuracy.

[0018] It should be understood that the descriptions of technical features, technical solutions, beneficial effects, or similar language in this application do not imply that all features and advantages can be achieved in any single embodiment. Rather, it is understood that the description of a feature or beneficial effect means that a specific technical feature, technical solution, or beneficial effect is included in at least one embodiment. Therefore, the descriptions of technical features, technical solutions, or beneficial effects in this specification do not necessarily refer to the same embodiment. Furthermore, the technical features, technical solutions, and beneficial effects described in this embodiment can be combined in any suitable manner. Those skilled in the art will understand that embodiments can be implemented without one or more specific technical features, technical solutions, or beneficial effects of a particular embodiment. In other embodiments, additional technical features and beneficial effects may be identified in specific embodiments that do not embody all embodiments. Attached Figure Description

[0019] Figure 1 A flowchart illustrating a method for diagnosing DPF faults provided in an embodiment of this application; Figure 2 A schematic diagram of a DPF system provided in an embodiment of this application; Figure 3 A schematic diagram of a DPF fault diagnostic device provided in an embodiment of this application; Figure 4 This is a schematic diagram of a computing device provided in an embodiment of this application. Detailed Implementation

[0020] The terms "first," "second," and "third," etc., used in this application specification and accompanying drawings are used to distinguish different objects, not to limit a specific order.

[0021] In the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design that is described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design. Specifically, the use of the terms "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0022] With the ongoing efforts to control air pollution, the demand for vehicle exhaust treatment is increasing daily. Currently, diesel vehicles account for 10% of the total vehicle fleet, but they account for over 99% of total vehicle particulate matter (PM) emissions, making them mobile sources of PM emissions.

[0023] Diesel particulate filters (DPFs) are a key technology for effectively reducing PM emissions from diesel vehicles. However, due to uncertainties in factors such as fuel quality, lubricant quality, and road conditions, the DPF system is affected by diesel engine operating conditions, ambient temperature, and the physicochemical properties of the carrier during practical application. This can lead to DPF failures and various problems, such as deteriorating engine power and fuel economy, causing DPF melting and cracking, and reducing DPF collection efficiency.

[0024] Currently, DPF fault diagnosis requires extensive testing and the establishment of DPF failure performance calibration models through manual calibration. This method has drawbacks: it requires complex electronic equipment, the calibration process is labor-intensive, and calibration engineers often use several fixed models when fitting performance models. This fails to address challenges such as high dependence on voltage drop, numerous variables affecting DPF performance, nonlinearity, and uncertainty. Consequently, the failure performance calibration model has poor predictive accuracy, leading to inaccurate fault diagnosis results, especially under transient conditions. Therefore, this diagnostic method is not only inefficient but also has poor accuracy.

[0025] In view of this, embodiments of this application provide a method for diagnosing DPF faults. This method can be executed by a vehicle, by a controller within the vehicle, or by a diagnostic device. This application does not specifically limit the entity executing this diagnostic method. Specifically, the method includes: Obtain the inlet and outlet measured temperatures, pipe wall temperature, exhaust mass flow rate, inner diameter, and length of the DPF's manifold; calculate the simulated outlet temperature of the manifold using the following formula: in, The simulated outlet temperature. Measure the temperature at the inlet. The tube wall temperature is... Let d be the derivative of the exhaust mass flow rate with respect to time, d be the inner diameter, k be the convective heat transfer coefficient, and c be the coefficient of mass flow rate. p , where x is the specific heat at constant pressure and x is the length of the shunt tube; calculate the temperature difference between the measured outlet temperature and the simulated outlet temperature. If the temperature difference corresponding to multiple consecutive calculation cycles is greater than the first predicted difference threshold, then the DPF is determined to be faulty.

[0026] This method performs fault diagnosis by comparing the simulated temperature and the measured temperature at the outlet of the shunt pipe, which can improve the diagnostic efficiency. By making diagnostic judgments when the temperature difference exceeds the first preset difference threshold multiple times, this method can improve the fault tolerance rate of the diagnosis, thereby improving the accuracy of the diagnosis.

[0027] To make the technical solution of this application clearer and easier to understand, the DPF fault diagnosis method provided in this application is described below with reference to the accompanying drawings. Figure 1 As shown, this figure is a flowchart of a DPF fault diagnosis method provided in an embodiment of this application. The method includes: S101. Obtain the inlet measurement temperature, outlet measurement temperature, pipe wall temperature, exhaust mass flow rate, inner diameter, and length of the DPF's manifold.

[0028] like Figure 2 As shown in the figure, this is a schematic diagram of a DPF system provided in an embodiment of this application. The system includes a first pressure sensor 201, a first differential pressure sensor 202, a first temperature sensor 203, a splitter pipe 204, a splitter pipe PM trap 205, a main exhaust pipe 206, a second pressure sensor 207, and a second temperature sensor 208.

[0029] Specifically, the first pressure sensor 201 measures the inlet pressure of the DPF, the first differential pressure sensor 202 measures the pressure difference between the DPF inlet and outlet, the first temperature sensor 203 measures the inlet temperature of the manifold 204, the second pressure sensor 207 measures the outlet pressure of the manifold, and the second temperature sensor 208 measures the outlet temperature of the manifold. The pipe wall temperature can be obtained using other temperature sensors, such as those located on the pipe wall.

[0030] The exhaust mass flow rate can be calculated using the following formula: in, Let be the derivative of the exhaust mass flow rate with respect to time. Let ρ be the exhaust volumetric flow rate of the diverter, ρ be the exhaust density, and d be the inner diameter. The exhaust velocity of the manifold.

[0031] In other embodiments, the above data may also be obtained in other ways; the above is merely an illustrative example.

[0032] S102. Calculate the simulated outlet temperature of the manifold using the formula.

[0033] The specific formula is as follows: in, The simulated outlet temperature. Measure the temperature at the inlet. The tube wall temperature is... Let d be the derivative of the exhaust mass flow rate with respect to time, d be the inner diameter, k be the convective heat transfer coefficient, and c be the coefficient of mass flow rate. p , where is the specific heat at constant pressure, and x is the length of the manifold.

[0034] In some embodiments, the vehicle needs to determine in advance whether the diagnostic conditions for DPF diagnosis are met before calculating the simulated outlet temperature of the shunt pipe and proceeding with subsequent diagnostic steps. This avoids misdiagnosis when the diagnostic conditions are not met, thereby improving the accuracy of the diagnostic results.

[0035] Specifically, the first carbon load of the DPF, the environmental parameters of the vehicle, and the operating parameters of the vehicle are obtained. Then, under the condition that the first carbon load of the DPF meets the first condition, the environmental parameters meet the second condition, and the operating parameters meet the third condition, the simulated outlet temperature of the shunt pipe is calculated.

[0036] For example, the first carbon loading of the DPF satisfies the first condition including the first carbon loading of the DPF being lower than a preset carbon loading threshold (e.g., 4 g / L) and the rate of change of the first carbon loading of the DPF being lower than a preset carbon loading change rate threshold (e.g., 0.01 g / (L·s)).

[0037] The environmental parameters include ambient temperature and atmospheric pressure. The environmental parameters satisfy the second condition, which includes the ambient temperature being in the first temperature range, the rate of change of ambient temperature being lower than the preset ambient temperature change rate threshold, the atmospheric pressure being in the first pressure range, and the rate of change of atmospheric pressure being lower than the preset atmospheric pressure change rate threshold.

[0038] Operating parameters include exhaust mass flow rate and inlet measurement temperature. The operating parameters must meet the third condition, which includes exhaust mass flow rate being greater than the preset exhaust mass flow rate threshold, inlet measurement temperature being in the second temperature range (e.g., 150℃-380℃), and the inlet measurement temperature growth rate being greater than the preset growth rate threshold (e.g., 0.5℃ / s).

[0039] Under the above conditions, the occurrence of misdiagnosis and false alarm can be further reduced, thereby improving the accuracy of DPF diagnosis.

[0040] In some embodiments, before calculating the simulated outlet temperature, a second carbon load deposited in the split-tube PM trap, located upstream of the split-tube, can be obtained. If the difference between this second carbon load and a preset value is greater than a second preset difference, it prompts the removal of carbon deposits from the split-tube PM trap. This reduces the impact of the second carbon load deposited in the split-tube PM trap on subsequent temperature calculations, further reducing diagnostic errors and improving the accuracy of diagnostic results.

[0041] In some embodiments, measurements of the engine's primary PM emissions and the exhaust flow rate at the DPF front end can be collected, thereby obtaining the exhaust mass flow rate of the downstream splitter pipe of the DPF and the calculated predicted value of the primary PM emissions. The ratio of the splitter exhaust mass flow rate to the main exhaust mass flow rate is the ratio of the splitter and main exhaust PM emissions. Multiplying this ratio by the predicted primary PM emissions value yields the carbon load deposited in the splitter PM trap. The primary PM emissions can be determined using the following formula: This is the predicted value of PM from the original emissions. , , For coefficients, This is a correction factor for the engine when operating at low exhaust flow rates. This is a correction factor for the engine operating at low air-fuel ratios, where P is the engine power or a physical quantity linearly related to engine power. The impact of instantaneous acceleration of the engine at low exhaust flow on PM emissions was considered; through The impact of sudden load increase and instantaneous acceleration on PM emissions when the engine is operating at a low air-fuel ratio was considered. Both factors are used to correct for the impact of transient operating conditions on PM emissions, and are obtained from tables regarding air-fuel ratio and power, respectively. The exponent c represents the nonlinear relationship between PM emissions and the rate of increase in engine power (the time derivative of power).

[0042] Generally, the carbon load of the split-tube PM trap should be close to zero. Analyzing the carbon load deposited within the split-tube PM trap provides a reference for its initial loading status. The split-tube PM trap must be kept clean before diagnosis. If a split-tube PM trap with carbon deposits is mistakenly considered clean, errors in the split-tube flow rate calculations mentioned earlier will lead to misdiagnosis. A qualitative carbon load model can alert staff that an initial split-tube carbon load exists before diagnosis, requiring the removal of carbon deposits first to ensure diagnostic reliability.

[0043] S103. Calculate the temperature difference between the measured outlet temperature and the simulated outlet temperature.

[0044] After obtaining the simulated outlet temperature of the manifold, the temperature difference between the measured outlet temperature and the simulated outlet temperature can be calculated.

[0045] In some examples, the measured outlet temperature and the corresponding simulated outlet temperature can be obtained at multiple time points within a cycle. The temperature difference at each time point is then calculated, summed, and averaged to obtain the final temperature difference. Specifically, the temperature difference can be calculated using the following formula: in, This is the final temperature difference value. For the first in a period Simulated outlet temperature at each time point For the first in a period The outlet temperature was measured at each time point. The number of time points in a cycle, for example, It can represent the first point in time.

[0046] It should be noted that the embodiments of this application are not limited to the above-mentioned method for calculating temperature difference. Other methods can also be used to calculate temperature difference, such as calculating temperature difference by weighted average.

[0047] S104. If the temperature difference corresponding to multiple consecutive calculation cycles is greater than the first preset difference threshold, then it is determined that the DPF is faulty.

[0048] In some embodiments, multiple consecutive calculation cycles can be two consecutive calculation cycles or more consecutive calculation cycles, such as four, but should be lower than a certain value, such as less than or equal to five, so as to ensure that the fault can be reported in a timely manner when a fault is found in the DPF.

[0049] Taking two consecutive calculation cycles as an example, if the temperature difference in the first calculation cycle is greater than a first preset difference threshold, and the temperature difference in the second calculation cycle is also greater than the first threshold difference, then it can be determined that the DPF is faulty. Here, the first and second calculation cycles are adjacent calculation cycles. In other embodiments, the number of times the temperature difference is greater than the first preset difference threshold can also be counted. If the temperature difference is greater than the first preset difference threshold for two consecutive calculation cycles, then it is determined that the DPF is faulty.

[0050] In some embodiments, after obtaining the temperature difference value, the severity of the temperature difference can be determined based on a pre-defined correspondence between reference temperature difference values ​​and reference severity levels. This correspondence can be obtained by fitting historical test samples. For example, if the DPF is pre-determined to be faulty, a two-dimensional graph is obtained by using multiple pre-defined temperature difference ranges as the horizontal axis and the frequency of the average temperature difference falling within a pre-defined range as the vertical axis. A curve is fitted based on the marked points on the two-dimensional graph, and the curve is processed to obtain the probability density function of the DPF damage level. Then, based on this probability density function of the DPF damage level and the temperature difference value, the severity of the damage can be determined, allowing the user to be notified as soon as possible to address the faulty DPF.

[0051] Based on the above, this application provides a method for diagnosing DPF faults. This method includes first obtaining the inlet measured temperature, outlet measured temperature, pipe wall temperature, exhaust mass flow rate, inner diameter, and branch pipe length of the DPF's manifold, and then calculating the simulated outlet temperature of the manifold using the following formula: in, The simulated outlet temperature. Measure the temperature at the inlet. The tube wall temperature is... Let d be the derivative of the exhaust mass flow rate with respect to time, d be the inner diameter, k be the convective heat transfer coefficient, and c be the coefficient of mass flow rate. p The specific heat is at constant pressure, and x is the length of the manifold. Next, the temperature difference between the measured outlet temperature and the simulated outlet temperature is calculated. If the temperature difference for multiple consecutive calculation cycles is greater than a first preset threshold, the DPF is determined to be faulty. This method improves diagnostic efficiency by comparing the simulated and measured temperatures at the shunt outlet. Furthermore, by using multiple diagnostic checks where the temperature difference exceeds the first preset threshold, the method increases the fault tolerance rate and thus improves diagnostic accuracy.

[0052] The above text combined Figures 1 to 2 The method for diagnosing DPF faults provided in the embodiments of this application has been described in detail. The apparatus and equipment provided in the embodiments of this application will be described below with reference to the accompanying drawings.

[0053] like Figure 3 As shown in the figure, this is a schematic diagram of a DPF fault diagnosis device provided in an embodiment of this application. The device includes: The acquisition module 301 is used to acquire the inlet measurement temperature, outlet measurement temperature, pipe wall temperature, exhaust mass flow rate, inner diameter, and length of the DPF's manifold. Calculation module 302 is used to calculate the simulated outlet temperature of the manifold using the following formula: in, The simulated outlet temperature. Measure the temperature at the inlet. The tube wall temperature is... Let d be the derivative of the exhaust mass flow rate with respect to time, d be the inner diameter, k be the convective heat transfer coefficient, and c be the coefficient of mass flow rate. p Let x be the specific heat at constant pressure and the length of the manifold; calculate the temperature difference between the measured outlet temperature and the simulated outlet temperature; The diagnostic module 303 is used to determine that the DPF is faulty if the temperature difference corresponding to multiple consecutive calculation cycles is greater than a first preset difference threshold.

[0054] In some possible implementations, the acquisition module 301 is further used to acquire the first carbon load of the DPF, the environmental parameters of the vehicle, and the operating parameters of the vehicle; the calculation module is specifically used to calculate the simulated outlet temperature of the shunt pipe when the first carbon load of the DPF meets the first condition, the environmental parameters meet the second condition, and the operating parameters meet the third condition.

[0055] In some possible implementations, the first carbon loading of the DPF satisfies a first condition, including: the first carbon loading of the DPF is lower than a preset carbon loading threshold, and the rate of change of the first carbon loading of the DPF is lower than a preset carbon loading change rate threshold; the environmental parameters include ambient temperature and atmospheric pressure; the environmental parameters satisfy a second condition, including: the ambient temperature is within a first temperature range, the rate of change of the ambient temperature is lower than a preset ambient temperature change rate threshold, the atmospheric pressure is within a first pressure range, and the rate of change of the atmospheric pressure is lower than a preset atmospheric pressure change rate threshold; the operating condition parameters include the exhaust mass flow rate and the inlet measured temperature; the operating condition parameters satisfy a third condition, including: the exhaust mass flow rate is greater than a preset exhaust mass flow rate threshold, the inlet measured temperature is within a second temperature range, and the rate of increase of the inlet measured temperature is greater than a preset rate of increase threshold.

[0056] In some possible implementations, the device further includes a prompting module; the acquisition module is further configured to acquire a second carbon load deposited in the split-tube PM trap, the split-tube PM trap being located upstream of the split-tube; the prompting module is configured to prompt the removal of carbon deposits from the split-tube PM trap if the difference between the second carbon load and a preset value is greater than a second preset difference.

[0057] In some possible implementations, the device further includes a determining module, which is used to determine the severity corresponding to the temperature difference based on a pre-set correspondence between a reference temperature difference and a reference severity.

[0058] The DPF fault diagnosis apparatus according to the embodiments of this application can correspondingly execute the method described in the embodiments of this application, and the above and other operations and / or functions of each module / unit of the DPF fault diagnosis apparatus are respectively for implementing Figure 1 For the sake of brevity, the corresponding processes of each method in the illustrated embodiments will not be described in detail here.

[0059] This application also provides computing devices, such as... Figure 4 As shown, this figure is a schematic diagram of a computing device provided in an embodiment of this application. Figure 4 As shown, the computing device 400 includes a bus 401, a processor 402, a communication interface 403, and a memory 404. The processor 402, the memory 404, and the communication interface 403 communicate with each other via the bus 401.

[0060] Bus 401 can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of representation, Figure 4 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0061] Processor 402 can be any one or more of the following processors: central processing unit (CPU), graphics processing unit (GPU), microprocessor (MP), or digital signal processor (DSP).

[0062] Communication interface 403 is used for communication with external devices.

[0063] Memory 404 may include volatile memory, such as random access memory (RAM). Memory 404 may also include non-volatile memory, such as read-only memory (ROM), flash memory, hard disk drive (HDD), or solid state drive (SSD).

[0064] The memory 404 stores executable code, and the processor 402 executes the executable code to perform the aforementioned DPF fault diagnosis method.

[0065] Specifically, in achieving Figure 3 In the case of the illustrated embodiment, and Figure 3 When the modules or units of the DPF fault diagnosis device described in the embodiment are implemented by software, the following steps are performed: Figure 3 The software or program code required for the functions of each module / unit can be partially or entirely stored in memory 404. Processor 402 executes the program code corresponding to each unit stored in memory 404 to perform the aforementioned DPF fault diagnosis method.

[0066] This application also provides a computer-readable storage medium. The computer-readable storage medium can be any available medium that a computing device can store, or a data storage device such as a data center containing one or more available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid-state drive). The computer-readable storage medium includes instructions that instruct the computing device to execute the DPF fault diagnosis method described above for a DPF fault diagnosis apparatus.

[0067] This application also provides a computer program product comprising one or more computer instructions. When the computer instructions are loaded and executed on a computing device, all or part of the processes or functions described in this application are generated.

[0068] The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions may be transmitted from one website, computer, or data center to another website, computer, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means.

[0069] When the computer program product is executed by a computer, the computer performs any of the aforementioned methods for diagnosing DPF faults. The computer program product can be a software installation package; when any of the aforementioned methods for diagnosing DPF faults is required, the computer program product can be downloaded and executed on the computer.

[0070] The descriptions of the processes or structures corresponding to the above figures each have their own emphasis. For parts of a process or structure that are not described in detail, please refer to the relevant descriptions of other processes or structures.

[0071] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions within the technical scope disclosed in this application should be covered within the scope of protection of this application.

Claims

1. A method for diagnosing DPF faults, characterized in that, include: The inlet temperature, outlet temperature, pipe wall temperature, exhaust mass flow rate, inner diameter, and length of the DPF's manifold are obtained. The manifold is located in the exhaust pipe downstream of the DPF. A manifold PM trap is installed on the manifold, and the manifold PM trap is located upstream of the manifold. The simulated outlet temperature of the manifold is calculated using the following formula: in, The simulated outlet temperature. Measure the temperature at the inlet. The tube wall temperature is... Let d be the derivative of the exhaust mass flow rate with respect to time, d be the inner diameter, k be the convective heat transfer coefficient, and c be the coefficient of mass flow rate. p The specific heat is at constant pressure, and x is the length of the manifold. Calculate the temperature difference between the measured outlet temperature and the simulated outlet temperature; If the temperature difference corresponding to multiple consecutive calculation cycles is greater than the first preset difference threshold, then the DPF is determined to be faulty.

2. The method according to claim 1, characterized in that, The method further includes: Obtain the first carbon load of the DPF, the environmental parameters of the vehicle, and the operating parameters of the vehicle. The calculation of the simulated outlet temperature of the shunt pipe includes: Calculate the simulated outlet temperature of the shunt pipe when the first carbon load of the DPF meets the first condition, the environmental parameters meet the second condition, and the operating condition parameters meet the third condition.

3. The method according to claim 2, characterized in that, The first carbon loading of the DPF satisfies a first condition, including: The first carbon loading of the DPF is lower than a preset carbon loading threshold, and the rate of change of the first carbon loading of the DPF is lower than a preset carbon loading change rate threshold. The environmental parameters include ambient temperature and atmospheric pressure; the environmental parameters satisfy the second condition, including: The ambient temperature is within a first temperature range, the rate of change of the ambient temperature is lower than a preset ambient temperature change rate threshold, and the atmospheric pressure is within a first pressure range, the rate of change of the atmospheric pressure is lower than a preset atmospheric pressure change rate threshold. The operating parameters include the exhaust mass flow rate and the inlet measured temperature; the operating parameters satisfy a third condition, including: The exhaust mass flow rate is greater than a preset exhaust mass flow rate threshold, the inlet measured temperature is in the second temperature range, and the growth rate of the inlet measured temperature is greater than a preset growth rate threshold.

4. The method according to claim 1, characterized in that, The method further includes: Obtain the second carbon loading deposited within the PM trap in the shunt pipe; If the difference between the second carbon load and the preset value is greater than the second preset difference, a prompt will be made to remove the carbon deposits in the PM collector of the diversion pipe.

5. The method according to any one of claims 1-4, characterized in that, The method further includes: The severity level corresponding to the temperature difference is determined based on a pre-defined correspondence between the reference temperature difference and the reference severity level.

6. A diagnostic device for DPF faults, characterized in that, include: The acquisition module is used to acquire the inlet measurement temperature, outlet measurement temperature, pipe wall temperature, exhaust mass flow rate, inner diameter, and length of the DPF's manifold. The manifold is located in the exhaust pipe downstream of the DPF, and a manifold PM trap is installed on the manifold, with the manifold PM trap located upstream of the manifold. The calculation module is used to calculate the simulated outlet temperature of the manifold using the following formula: in, The simulated outlet temperature. Measure the temperature at the inlet. The tube wall temperature is... Let d be the derivative of the exhaust mass flow rate with respect to time, d be the inner diameter, k be the convective heat transfer coefficient, and c be the coefficient of mass flow rate. p Let x be the specific heat at constant pressure and the length of the manifold; calculate the temperature difference between the measured outlet temperature and the simulated outlet temperature; The diagnostic module is used to determine that the DPF is faulty if the temperature difference corresponding to multiple consecutive calculation cycles is greater than a first preset difference threshold.

7. The apparatus according to claim 6, characterized in that, The acquisition module is also used to acquire the first carbon load of the DPF, the environmental parameters of the vehicle, and the operating parameters of the vehicle. The calculation module is specifically used to calculate the simulated outlet temperature of the shunt pipe when the first carbon load of the DPF meets the first condition, the environmental parameters meet the second condition, and the operating condition parameters meet the third condition.

8. The apparatus according to claim 7, characterized in that, The first carbon loading of the DPF satisfies a first condition, including: The first carbon loading of the DPF is lower than a preset carbon loading threshold, and the rate of change of the first carbon loading of the DPF is lower than a preset carbon loading change rate threshold. The environmental parameters include ambient temperature and atmospheric pressure; the environmental parameters satisfy the second condition, including: The ambient temperature is within a first temperature range, the rate of change of the ambient temperature is lower than a preset ambient temperature change rate threshold, and the atmospheric pressure is within a first pressure range, the rate of change of the atmospheric pressure is lower than a preset atmospheric pressure change rate threshold. The operating parameters include the exhaust mass flow rate and the inlet measured temperature; the operating parameters satisfy a third condition, including: The exhaust mass flow rate is greater than a preset exhaust mass flow rate threshold, the inlet measured temperature is in the second temperature range, and the growth rate of the inlet measured temperature is greater than a preset growth rate threshold.

9. A computing device, characterized in that, Including memory and processor; The memory stores one or more computer programs, the one or more computer programs including instructions; when the instructions are executed by the processor, the computing device performs the method as described in any one of claims 1 to 5.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium is used to store a computer program for performing the method as described in any one of claims 1 to 5.

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