A fault diagnosis method and device for a particle trap and a vehicle

Abstract

The application provides a particle trap fault diagnosis method and device and a vehicle, and relates to the technical field of vehicles. The particle trap fault diagnosis method comprises the following steps: acquiring vehicle working condition data and a pipe actual pressure value collected by a pressure detection device; determining a pipe model pressure value corresponding to the pipe of the particle trap when the particle trap is normally operated according to the vehicle working condition data; and comparing the pipe actual pressure value with the pipe model pressure value, and judging whether a pipe shedding fault occurs. The pipe model pressure value when the particle trap is normally operated is used as a reference value, and whether the pipe shedding fault occurs is judged according to the comparison result of the pipe actual pressure value and the pipe model pressure value, so that the accuracy of the pipe shedding fault diagnosis is improved.

Description

Technical Field

[0001] This invention relates to the field of vehicle technology, and more specifically, to a method, apparatus, and vehicle for diagnosing particulate filters. Background Technology

[0002] As environmental protection requirements for the quantity and weight of particulate matter in vehicle exhaust become increasingly stringent, GPF (Gasoline Particulate Filter) has gradually become an indispensable device in gasoline engine aftertreatment systems. GPFs are typically installed at the exhaust end of gasoline engines, and their core component is a filter element supported by metal fiber felt or honeycomb ceramic. This filter element can remove most of the particulate matter in vehicle exhaust, thus purifying the exhaust. Because GPF malfunctions can lead to excessive pollutants in vehicle exhaust emissions, it is necessary to diagnose GPF malfunctions and monitor its status.

[0003] In existing technologies, the fault diagnosis method for Gasoline Processing Units (GPPFs) involves adding a single-diaphragm differential pressure sensor to the gasoline engine's aftertreatment system. This sensor is connected to the upstream and downstream of the GPF via two pipes to detect the pressure difference between them. Faults are then diagnosed based on changes in this pressure difference. However, the single-diaphragm differential pressure sensor can only detect the pressure difference between the upstream and downstream pipes, not the absolute pressure within those pipes. Therefore, fault diagnosis based solely on the pressure difference cannot effectively diagnose pipe detachment faults, leading to missed or false alarms. Summary of the Invention

[0004] The problem addressed by this invention is how to improve the diagnostic accuracy of pipeline detachment faults.

[0005] To address the above problems, the present invention provides a method, apparatus, and vehicle for diagnosing particulate traps.

[0006] In a first aspect, the present invention provides a fault diagnosis method for a particulate trap, based on a pressure detection device, one end of which is connected upstream of the particulate trap via an upstream pipeline, and the other end of which is connected downstream of the particulate trap via a downstream pipeline. The fault diagnosis method for the particulate trap includes:

[0007] Acquire vehicle operating condition data and the measured pressure values ​​of the pipeline collected by the pressure detection device, wherein the measured pressure values ​​of the pipeline include the upstream measured pressure value of the upstream pipeline and / or the downstream measured pressure value of the downstream pipeline.

[0008] The pipeline model pressure value of the corresponding pipeline when the particulate filter is operating normally is determined based on the vehicle operating condition data.

[0009] The measured pressure value of the pipeline and the pipeline model pressure value are compared and processed to determine whether a pipeline shedding fault occurs.

[0010] Optionally, the pressure detection device includes a double-membrane differential pressure sensor.

[0011] Optionally, the vehicle working condition data includes at least one of engine speed, engine load, and vehicle speed.

[0012] Optionally, the comparison and processing of the measured pressure value of the pipeline and the pipeline model pressure value to determine whether a pipeline shedding fault occurs includes:

[0013] determining a first pressure difference value between the measured pressure value of the pipeline and atmospheric pressure, and a second pressure difference value between the pipeline model pressure value and atmospheric pressure;

[0014] determining the square of the first pressure difference value to obtain a measured pressure difference energy value, and determining the square of the second pressure difference value to obtain a model pressure difference energy value;

[0015] The measured pressure difference energy value and the model pressure difference energy value are compared and processed to determine whether the pipeline shedding fault occurs.

[0016] Optionally, the comparison and processing of the measured pressure difference energy value and the model pressure difference energy value to determine whether the pipeline shedding fault occurs includes:

[0017] determining a ratio between the measured pressure difference energy value and the model pressure difference energy value to obtain an energy ratio value;

[0018] comparing the energy ratio value with a preset threshold value, and determining whether the pipeline shedding fault occurs according to a comparison result.

[0019] Optionally, the determination of whether the pipeline shedding fault occurs according to the comparison result includes:

[0020] when the energy ratio value is less than the preset threshold value, determining that a pipeline error occurs;

[0021] recording a comparison frequency of the energy ratio value and the preset threshold value at different collection times, and an error frequency of the pipeline error;

[0022] when a ratio of the error frequency and the comparison frequency is greater than a preset percentage threshold value, determining that the pipeline shedding fault occurs.

[0023] Optionally, the determination of the pipeline model pressure value of the pipeline corresponding to the normal operation of the particulate trap according to the vehicle working condition data includes:

[0024] Determine the pipeline model pressure value corresponding to the vehicle working condition data in a preset correspondence relationship, the preset correspondence relationship including the vehicle working condition data and the corresponding pipeline model pressure value, the pipeline model pressure value including the upstream model pressure value of the upstream pipeline and / or the downstream model pressure value of the downstream pipeline.

[0025] Optionally, the fault diagnosis method of the particle trap further includes:

[0026] Determine the measured pressure difference value between the upstream measured pressure value and the downstream measured pressure value at a plurality of continuous different collection time points, and the model pressure difference value between the upstream model pressure value and the downstream model pressure value at each collection time point;

[0027] Determine the first change amount between the model pressure difference value at a current collection time point and the model pressure difference value at a previous collection time point, and the second change amount between the measured pressure difference value at the current collection time point and the measured pressure difference value at a previous time point, the current collection time point being any one of the collection time points;

[0028] Compare the first change amount and the second change amount to determine whether the particle trap removal fault occurs.

[0029] Optionally, the comparing the first change amount and the second change amount to determine whether the particle trap removal fault occurs includes:

[0030] Take the first change amount as the model pressure difference gradient at the current collection time point, and take the second change amount as the measured pressure difference gradient at the current collection time point;

[0031] Determine the first function of the model pressure difference gradient with respect to time and the second function of the model pressure difference gradient with respect to the deviation time value according to the model pressure difference gradient at each collection time point, and determine the third function of the measured pressure difference gradient with respect to the deviation time value according to the measured pressure difference gradient at each collection time point, wherein the deviation time value is the sum of the time and the time interval between adjacent two collection time points, and the time interval between each adjacent two collection time points is the same;

[0032] Multiply the first function and the second function to obtain a model pressure difference function, and multiply the first function and the third function to obtain a measured pressure difference function;

[0033] Integrate the model pressure difference function according to time within a preset time interval to obtain a model pressure difference integral value, and integrate the measured pressure difference function according to time to obtain a measured pressure difference integral value;

[0034] determining a ratio between the measured differential pressure integral value and the model differential pressure integral value to obtain a differential pressure gradient correlation number;

[0035] determining whether the differential pressure gradient correlation number is within a preset fault threshold range, and determining whether the particle trap removal fault occurs according to a determination result.

[0036] Optionally, the determining whether the particle trap removal fault occurs according to the determination result comprises:

[0037] when the differential pressure gradient correlation number is within the preset fault threshold range, determining that a particle trap error occurs;

[0038] when a number of times of occurrence of the particle trap error reaches a preset number limit, determining that the particle trap removal fault occurs.

[0039] In a second aspect, the present application provides a fault diagnosis device of a particle trap, which is based on a pressure detection device, one end of the pressure detection device is connected to an upstream of the particle trap through an upstream pipeline, and the other end of the pressure detection device is connected to a downstream of the particle trap through a downstream pipeline, and the fault diagnosis device of the particle trap comprises:

[0040] an acquisition module, configured to acquire vehicle working condition data and pipeline measured pressure values collected by the pressure detection device, the pipeline measured pressure values comprising an upstream measured pressure value of the upstream pipeline and / or a downstream measured pressure value of the downstream pipeline;

[0041] a processing module, configured to determine a pipeline model pressure value of a corresponding pipeline of the particle trap when the particle trap is normally operated according to the vehicle working condition data;

[0042] a judgment module, configured to compare and process the pipeline measured pressure values and the pipeline model pressure value, and determine whether a pipeline shedding fault occurs.

[0043] In a third aspect, the present application provides a vehicle, comprising a memory and a processor;

[0044] the memory, configured to store a computer program;

[0045] the processor, configured to implement the fault diagnosis method of the particle trap as described in the first aspect when the computer program is executed.

[0046] The particle trap fault diagnosis method, device and vehicle of the present application have the following beneficial effects: the pressure detection device is used to collect the upstream measured pressure value upstream of the particle trap (i.e. the upstream pipeline) and / or the downstream measured pressure value downstream of the particle trap (i.e. the downstream pipeline). The vehicle working condition data and the pipeline measured pressure value collected by the pressure detection device are obtained, and the pipeline measured pressure value of one pipeline is not affected by the pressure of the other pipeline, for example, the pipeline measured pressure value of the upstream pipeline is not affected by the pressure of the downstream pipeline. The vehicle working condition data can include at least one of engine load, engine speed and vehicle speed. The pipeline model pressure value of the particle trap under normal operation is determined according to the vehicle working condition data, and the pipeline model pressure value is fixed under the corresponding vehicle working condition. The pipeline model measured pressure value and the pipeline model pressure value are compared with the pipeline model pressure value as the reference value, and the comparison result can accurately judge whether the pipeline shedding fault occurs, thereby improving the diagnosis accuracy of the pipeline shedding fault. BRIEF DESCRIPTION OF DRAWINGS

[0047] Figure 1 A structure schematic diagram of a pressure detection device according to an embodiment of the present application;

[0048] Figure 2 A flowchart of a particle trap fault diagnosis method according to an embodiment of the present application;

[0049] Figure 3 A flowchart of another particle trap fault diagnosis method according to an embodiment of the present application;

[0050] Figure 4 A flowchart of still another particle trap fault diagnosis method according to an embodiment of the present application;

[0051] Figure 5 A waveform schematic diagram of various diagnosis data when concurrent faults of particle trap removal + upstream pipeline shedding occur according to an embodiment of the present application;

[0052] Figure 6 A waveform schematic diagram of various diagnosis data when concurrent faults of particle trap removal + downstream pipeline shedding occur according to an embodiment of the present application;

[0053] Figure 7 A structure schematic diagram of a particle trap fault diagnosis device according to an embodiment of the present application.

[0054] REFERENCE SIGNS:

[0055] 1, catalytic converter; 2, particle trap; 3, pressure detection device; 4, upstream pipeline; 5, downstream pipeline; 6, muffler. DETAILED DESCRIPTION

[0056] In order to make the above objectives, characteristics and advantages of the present application more obvious and comprehensible, specific embodiments of the present application are described in detail below with reference to the drawings. Although some embodiments of the present application are shown in the drawings, it should be understood that the present application can be implemented in various forms, and should not be interpreted as being limited to the embodiments set forth herein, but rather, these embodiments are provided to make the present application more thorough and complete. It should be understood that the drawings and embodiments of the present application are only for exemplary purposes, and are not intended to limit the scope of protection of the present application.

[0057] It should be understood that each step described in the method embodiments of the present application can be performed in different orders and / or in parallel. In addition, the method embodiments can include additional steps and / or omit the steps shown. The scope of the present application is not limited in this respect.

[0058] The term "comprising" and variations thereof as used herein are open-ended, that is "including but not limited to". The term "based on" is "based, at least in part, on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments"; the term "optional" means "optional in at least some embodiments". Related definitions are given throughout the description. It should be noted that the concepts "first", "second" and the like mentioned in the present application are only used to distinguish different devices, modules or units, and do not imply the order or interdependence of the functions performed by these devices, modules or units.

[0059] It should be noted that the modification of "one" or "multiple" mentioned in the present application is illustrative rather than limiting, and those skilled in the art should understand that unless otherwise explicitly indicated in the context, it should be understood as "one or more".

[0060] The names of the messages or information exchanged between the devices in the embodiments of the present application are only for illustrative purposes, and are not intended to limit the scope of the messages or information.

[0061] In the prior art, the upstream and downstream pressure difference of the particle trap is usually collected by a single membrane pressure difference sensor, and the change of the upstream and downstream pressure difference is monitored to diagnose the particle trap and pipeline shedding faults according to the change. Specifically, after obtaining the upstream and downstream pressure difference signal output by the single membrane pressure difference sensor, the upstream and downstream pressure difference is obtained by low-pass filtering, the square of the upstream and downstream pressure difference is calculated to obtain the pressure difference energy value; the pressure difference energy value is compared with the preset threshold value, and whether an error occurs is judged according to the comparison result; the comparison times of the pressure difference energy and the preset threshold value, and the error times of the error occurring in the comparison process are recorded, the ratio of the error times to the comparison times is compared with the preset percentage threshold value to diagnose the downstream pipeline shedding fault and the particle trap removal fault.

[0062] It should be noted that, under normal circumstances, the pressure in the upstream pipeline is usually greater than the pressure in the downstream pipeline, and both are greater than atmospheric pressure.

[0063] Single-diaphragm differential pressure sensors can only collect the pressure difference between upstream and downstream pipelines, and cannot output the absolute pressure values ​​of upstream and downstream pipelines. This leads to the following three problems with existing fault diagnosis methods:

[0064] (1) When the upstream pipeline is disconnected, the single-diaphragm differential pressure sensor measures the pressure difference between atmospheric pressure and downstream pipeline. It can only make accurate diagnoses under heavy load conditions and cannot distinguish between two faults: upstream pipeline disconnection and pipeline reversal. For example, when the upstream pipeline is disconnected, the pressure difference between atmospheric pressure and downstream pipeline is negative. When the upstream and downstream pipelines are reversed, the pressure difference detected by the sensor is also negative, which makes it impossible to distinguish between the two faults.

[0065] (2) When the downstream pipeline detaches, the single-membrane differential pressure sensor measures the pressure difference between the upstream pipeline and atmospheric pressure. The pressure difference energy value of the downstream pipeline detachment overlaps with that of the normal pipeline. Therefore, the existing diagnostic method cannot accurately diagnose whether the downstream pipeline has detached under certain operating conditions. For example, when the downstream pipeline pressure is close to atmospheric pressure, the diagnostic results may be incorrect.

[0066] (3) It is not possible to diagnose the faults of particle trap removal + upstream pipe detachment and particle trap removal + downstream pipe detachment at the same time when the particle trap is removed, which poses a risk of missed or false alarms.

[0067] To address the problem that existing technologies cannot effectively diagnose pipeline detachment faults and related superimposed faults in upstream and downstream of particulate traps, embodiments of the present invention provide a fault diagnosis method, device, vehicle, and computer-readable storage medium for particulate traps.

[0068] like Figure 1 As shown in the figure, an embodiment of the present invention provides a pressure detection device 3, one end of which is connected to the upstream of the particle trap 2 via an upstream pipeline 4, and the other end of which is connected to the downstream of the particle trap 2 via a downstream pipeline 5.

[0069] Specifically, the particulate trap 2 is located between the catalyst 1 and the muffler 6. One end of the pressure detection device 3 is connected to one end of the upstream pipeline 4, and the other end of the upstream pipeline 4 is installed between the catalyst 1 and the particulate trap 2. The other end of the pressure detection device 3 is connected to one end of the downstream pipeline 5, and the other end of the downstream pipeline 5 is installed between the particulate trap 2 and the muffler 6.

[0070] The upstream of the particulate trap 2 represents the gas inlet end of the particulate trap 2, i.e. the pipeline between the particulate trap 2 and the catalytic converter 1; the downstream of the particulate trap 2 represents the gas outlet end of the particulate trap 2, i.e. the pipeline between the particulate trap 2 and the muffler 6. The pressure detection device 3 is configured to collect the upstream measured pressure value in the upstream pipeline 4 and the downstream measured pressure value in the downstream pipeline 5.

[0071] For example, the pressure detection device 3 can include a double diaphragm differential pressure sensor, which adopts a double diaphragm absolute pressure technology, and is internally provided with two pressure sensitive elements, a chip processor and a digital converter. The two pressure sensitive elements are respectively configured to sense the absolute pressures upstream and downstream of the particulate trap 2, the chip processor is configured to process the pressure signals upstream and downstream, and the digital converter is configured to convert the analog signals into digital signals. The double diaphragm differential pressure sensor can simultaneously output the upstream absolute pressure value, the downstream absolute pressure value and the differential pressure value between the upstream and the downstream.

[0072] The pressure detection device 3 can also include two pressure sensors, one of which is connected to the upstream of the particulate trap 2 through the upstream pipeline 4 and configured to collect the upstream absolute pressure value, and the other of which is connected to the downstream of the particulate trap 2 through the downstream pipeline 5 and configured to collect the downstream absolute pressure value. The two pressure sensors are respectively connected to a controller, and the controller is configured to process the upstream absolute pressure value and the downstream absolute pressure value to obtain the differential pressure value between the upstream and the downstream.

[0073] In this embodiment, the pressure detection device 3 can detect the upstream measured pressure value in the upstream pipeline 4 and the downstream measured pressure value in the downstream pipeline 5, and the differential pressure value between the upstream and the downstream can be determined according to the upstream measured pressure value and the downstream measured pressure value. The various pressure information provides sufficient data for the fault diagnosis of the particulate trap 2, and can improve the accuracy of subsequent fault diagnosis.

[0074] As shown in FIG. 1, Figure 2 The fault diagnosis method of the particulate trap provided by the embodiment of the present application is based on the pressure detection device 3 as described above, and includes the following steps.

[0075] S100, acquiring vehicle working condition data and pipeline measured pressure values collected by the pressure detection device, wherein the pipeline measured pressure values include the upstream measured pressure value of the upstream pipeline and / or the downstream measured pressure value of the downstream pipeline.

[0076] Specifically, the vehicle working condition data can include at least one of the engine speed, the engine load and the vehicle speed, and the pressure detection device is configured to collect the upstream measured pressure value P1 of the upstream of the particulate trap (i.e. the upstream pipeline) and / or the downstream measured pressure value P2 of the downstream of the particulate trap (i.e. the downstream pipeline).

[0077] Specifically, the upstream pressure signal and the downstream pressure signal collected by the double diaphragm differential pressure sensor can be acquired, and low-pass digital filtering processing is performed on the two pressure signals, and the filtering cutoff frequency can be 3.5 Hz, to obtain the upstream measured pressure value P1 and the downstream measured pressure value P2.

[0078] In S200, a pipe model pressure value corresponding to the pipe when the particulate trap is in normal operation is determined according to the vehicle working condition data.

[0079] Specifically, the pipe model pressure value can include an upstream model pressure value P1m upstream of the particulate trap and / or a downstream model pressure value P2m downstream of the particulate trap.

[0080] A corresponding relationship or model can be established in advance according to historical data (historical vehicle working condition data and corresponding pipe model pressure values) when the particulate trap is in normal operation. When the vehicle working condition data at the current time is acquired, the corresponding pipe model pressure value can be calculated according to the model, or determined in the corresponding relationship.

[0081] In S300, the pipe measured pressure value and the pipe model pressure value are compared, and it is determined whether a pipe shedding fault occurs.

[0082] Exemplarily, the pipe measured pressure value and the pipe model pressure value can be compared, and it is determined whether a pipe shedding fault occurs according to the comparison result. The difference between the pipe measured pressure value and the pipe model pressure value can also be determined, and the difference is compared with a corresponding threshold value, and when the difference is greater than the corresponding threshold value, it is determined that a pipe shedding fault occurs.

[0083] Specifically, the pipe shedding fault can include an upstream pipe shedding fault and / or a downstream pipe shedding fault.

[0084] When the pipe measured pressure value is the upstream measured pressure value, the upstream model pressure value when the particulate trap is in normal operation is determined according to the vehicle working condition data, the upstream measured pressure value and the upstream model pressure value are compared, and it is determined whether an upstream pipe shedding fault occurs according to the comparison result.

[0085] When the pipe measured pressure value is the downstream measured pressure value, the downstream model pressure value when the particulate trap is in normal operation is determined according to the vehicle working condition data, the downstream measured pressure value and the downstream model pressure value are compared, and it is determined whether a downstream pipe shedding fault occurs according to the comparison result.

[0086] In this embodiment, the vehicle working condition data and the pipe measured pressure value collected by the pressure detection device are obtained. The pipe measured pressure value of one pipe is not affected by the pressure of another pipe, for example, the pipe measured pressure value of the upstream pipe is not affected by the pressure of the downstream pipe. The vehicle working condition data can include at least one of engine load, engine speed and vehicle speed. The pipe model pressure value of the particulate trap under normal operation is determined according to the vehicle working condition data. The pipe model pressure value is fixed under the corresponding vehicle working condition. The pipe model measured pressure value and the pipe model pressure value are compared with the pipe model pressure value as the reference value. According to the comparison result, whether the pipe shedding fault occurs can be accurately judged, and the diagnosis accuracy of the pipe shedding fault is improved.

[0087] Optionally, as shown in Figure 3 The comparison processing of the pipe measured pressure value and the pipe model pressure value to determine whether the pipe shedding fault occurs includes:

[0088] S310, determining a first pressure difference value between the pipe measured pressure value and the atmospheric pressure, and a second pressure difference value between the pipe model pressure value and the atmospheric pressure;

[0089] S320, determining the square of the first pressure difference value to obtain a measured pressure difference energy value; determining the square of the second pressure difference value to obtain a model pressure difference energy value;

[0090] S330, comparing the measured pressure difference energy value and the model pressure difference energy value to determine whether the pipe shedding fault occurs.

[0091] Exemplarily, taking the pipe measured pressure value as the upstream measured pressure value P1 and the pipe model pressure value as the upstream model pressure value P1m as an example, assuming that the atmospheric pressure is P0. First, determine the first pressure difference value P1-P0 between the upstream measured pressure value P1 and the atmospheric pressure P0, and the second pressure difference value P1m-P0 between the upstream model pressure value P1m and the atmospheric pressure P0. The square of the first pressure difference value P1-P0 is the upstream measured pressure difference energy value, and the square of the second pressure difference value P1m-P0 is the upstream model pressure difference energy value. Comparing the upstream measured pressure difference energy value and the upstream model pressure difference energy value, if the upstream measured pressure difference energy value is less than the upstream model pressure difference energy value, it is determined that the upstream pipe shedding fault may occur. Alternatively, the upstream energy difference value between the upstream model pressure difference energy value and the upstream measured pressure difference energy value can be determined, and the upstream energy difference value is compared with a preset energy threshold value. If the upstream energy difference value is greater than the preset energy threshold value, it is determined that the upstream pipe shedding fault may occur.

[0092] Taking the pipe measured pressure value as the downstream measured pressure value P2, the pipe model pressure value as the downstream model pressure value P2m, and assuming the atmospheric pressure as P0. First, determine the first pressure difference value P2-P0 between the downstream measured pressure value P2 and the atmospheric pressure P0, and the second pressure difference value P2m-P0 between the downstream model pressure value P2m and the atmospheric pressure P0. Determine the square of the first pressure difference value P2-P0 as the downstream measured pressure difference energy value, and the square of the second pressure difference value P2m-P0 as the downstream model pressure difference energy value. Compare the downstream measured pressure difference energy value with the downstream model pressure difference energy value. If the downstream measured pressure difference energy value is less than the downstream model pressure difference energy value, it is determined that the downstream pipe may have a shedding fault. Alternatively, a downstream energy difference value between the downstream model pressure difference energy value and the downstream measured pressure difference energy value can be determined, and the downstream energy difference value is compared with a preset energy threshold value. If the downstream energy difference value is greater than the preset energy threshold value, it is determined that the downstream pipe may have a shedding fault.

[0093] In this optional embodiment, the measured pressure difference energy value is calculated according to the first pressure difference value between the pipe measured pressure value and the atmospheric pressure, and the measured pressure difference energy value is calculated according to the second pressure difference value between the pipe model pressure value and the atmospheric pressure. The atmospheric pressure remains unchanged, so that the calculated measured pressure difference energy value of a single pipe is not affected by the pressure of another pipe, for example, the measured pressure difference energy value of the upstream pipe is not affected by the pressure of the downstream pipe. Comparing the model pressure difference energy value calculated by the pipe model pressure value corresponding to the normal operation of the particulate trap with the measured pressure difference energy value can accurately diagnose whether a pipe shedding fault occurs.

[0094] Optionally, the comparing the measured pressure difference energy value and the model pressure difference energy value to determine whether the pipe shedding fault occurs includes:

[0095] S331, determining a ratio between the measured pressure difference energy value and the model pressure difference energy value to obtain an energy ratio value;

[0096] S332, comparing the energy ratio value with a preset threshold value to determine whether the pipe shedding fault occurs according to the comparison result.

[0097] For example, taking the upstream pipe as an example, the ratio between the upstream measured pressure difference energy value and the upstream model pressure difference energy value is determined as an upstream energy ratio value E1. The upstream energy ratio value E1 is compared with a preset threshold value. When the upstream energy ratio value E1 is less than the preset threshold value, it is determined that the upstream pipe may have a shedding fault.

[0098] For example, taking the downstream pipe as an example, the ratio between the downstream measured pressure difference energy value and the downstream model pressure difference energy value is determined as a downstream energy ratio value E2. The downstream energy ratio value E2 is compared with a preset threshold value. When the downstream energy ratio value E2 is less than the preset threshold value, it is determined that the downstream pipe may have a shedding fault.

[0099] Specifically, the closer the upstream energy ratio E1 and the downstream energy ratio E2 are to 1, the more likely the upstream pipeline and the downstream pipeline are normal; the closer the upstream energy ratio E1 and the downstream energy ratio E2 are to 0, the more likely the upstream pipeline and the downstream pipeline are off.

[0100] Optionally, the determining whether the pipeline off fault occurs according to the comparison result comprises:

[0101] When the energy ratio is less than the preset threshold, it is determined that the pipeline error occurs;

[0102] The comparison times of the energy ratio and the preset threshold and the error times of the pipeline error are recorded at different collection moments;

[0103] When the ratio of the error times and the comparison times is greater than a preset percentage threshold, it is determined that the pipeline off fault occurs.

[0104] Exemplarily, taking the upstream pipeline as an example, when the upstream energy ratio E1 is less than the preset threshold, it is determined that the upstream pipeline error occurs. The vehicle working condition data and the upstream pipeline measured pressure value at each collection moment are monitored, and after each collection moment data is processed through the above process, the comparison times of the upstream energy ratio E1 and the preset threshold and the upstream error times of the upstream pipeline error are recorded. The ratio of the upstream error times and the comparison times is compared with the preset percentage threshold, and when the ratio is greater than the preset percentage threshold, it is determined that the upstream pipeline off fault occurs.

[0105] Taking the downstream pipeline as an example, when the downstream energy ratio E2 is less than the preset threshold, it is determined that the downstream pipeline error occurs. The vehicle working condition data and the downstream pipeline measured pressure value at each collection moment are monitored, and after each collection moment data is processed through the above process, the comparison times of the downstream energy ratio E2 and the preset threshold and the downstream error times of the downstream pipeline error are recorded. The ratio of the downstream error times and the comparison times is compared with the preset percentage threshold, and when the ratio is greater than the preset percentage threshold, it is determined that the downstream pipeline off fault occurs.

[0106] Specifically, it is judged whether the energy ratio is less than the preset threshold, and when the energy ratio is less than the preset threshold, the measured differential pressure energy value is less than the model differential pressure energy value, i.e. the first differential pressure value between the pipeline measured pressure value and the atmospheric pressure is less than the second differential pressure value between the pipeline model pressure value and the atmospheric pressure, the pipeline measured pressure value is closer to the atmospheric pressure, and the pipeline error is likely to occur. When the energy ratio is greater than or equal to the preset threshold, the vehicle working condition data and the pipeline measured pressure value collected by the pressure detection device are acquired, i.e. the vehicle working condition and the upstream and downstream pressures of the particulate filter are continuously monitored.

[0107] determining whether the ratio of the number of errors to the number of comparisons is greater than a preset percentage threshold, if yes, determining that the pipe falling off fault occurs, if no, determining that the pipe is normal at the current collection time, returning to acquire the vehicle working condition data and the pipe measured pressure value collected by the pressure detection device, that is, continuing to monitor the vehicle working condition and the upstream and downstream pressures of the particle trap.

[0108] In the optional embodiment, the number of comparisons of the energy ratio at different collection times with the preset threshold value and the number of errors of the comparison results of the pipe error are recorded, and the ratio of the number of errors to the total number of comparisons is compared with the preset percentage threshold value. When the ratio is greater than the preset percentage threshold value, it indicates that the pipe error occurs frequently, at this time, it is determined that the pipe falling off fault occurs, and the preset percentage threshold value can be set to 2%. Compared with directly judging whether the pipe falling off fault occurs according to the comparison result of the energy ratio at a single time with the preset threshold value, the accuracy of fault diagnosis is confirmed by multiple comparison results, which can avoid false reporting of faults and improve the diagnosis accuracy of the pipe falling off fault.

[0109] Optionally, the determining the pipe model pressure value of the pipe corresponding to the particle trap in normal operation according to the vehicle working condition data comprises:

[0110] determining the pipe model pressure value corresponding to the vehicle working condition data in a preset correspondence relationship, the preset correspondence relationship comprising the vehicle working condition data and the corresponding pipe model pressure value, the pipe model pressure value comprising an upstream model pressure value of the upstream pipe and / or a downstream model pressure value of the downstream pipe.

[0111] Specifically, the pipe model pressure values corresponding to different vehicle working conditions when the particle trap is in normal operation can be determined in advance through calibration to establish a preset correspondence relationship between the vehicle working condition data and the pipe model pressure value. When the vehicle working condition data at the current time is acquired, the pipe model pressure value corresponding to the vehicle working condition data can be directly found in the preset correspondence relationship. The pipe model pressure value can include an upstream model pressure value and a downstream model pressure value, and the preset correspondence relationship can be stored in the form of a chart and a database.

[0112] Optionally, as shown in Figure 4 the fault diagnosis method of the particle trap further comprises:

[0113] S410, determining the measured pressure difference value between the upstream measured pressure value and the downstream measured pressure value at a plurality of continuous different collection times, and the model pressure difference value between the upstream model pressure value and the downstream model pressure value at each collection time.

[0114] Specifically, the upstream measured pressure value P1 and the downstream measured pressure value P2 can be collected once every same time interval, i.e., the time interval between every two adjacent collection time points is the same, and the upstream model pressure value P1m and the downstream model pressure value P2m at each collection time point are determined.

[0115] The upstream measured pressure value P1 is subtracted from the downstream measured pressure value P2 to obtain a measured pressure difference value ΔP, i.e., ΔP = P1-P2. Alternatively, a pressure difference signal output by the double-membrane pressure difference sensor can be directly obtained, and the pressure difference signal is subjected to low-pass digital filtering processing, and the filtering cutoff frequency can be 3.5 Hz to obtain the measured pressure difference value ΔP.

[0116] The upstream model pressure value P1m is subtracted from the downstream model pressure value P2m to obtain a model pressure difference value ΔPm, i.e., ΔPm = P1m-P2m.

[0117] S420, determining a first change amount between the model pressure difference value at a current collection time point and the model pressure difference value at a previous collection time point, and a second change amount between the measured pressure difference value at the current collection time point and the measured pressure difference value at a previous time point, the current collection time point being any one of the collection time points.

[0118] Specifically, the first change amount between the model pressure difference values at every two adjacent collection time points is calculated, and the first change amount can be represented as ΔPm(t)-ΔPm(t-Δt), t representing the current collection time point, Δt representing the time interval, ΔPm(t) representing the model pressure difference value at the current collection time point, and ΔPm(t-Δt) representing the model pressure difference value at the previous collection time point.

[0119] The second change amount between the measured pressure difference values at every two adjacent collection time points is also calculated, and the second change amount can be represented as ΔP(t)-ΔP(t-Δt), t representing the current collection time point, Δt representing the time interval, ΔP(t) representing the measured pressure difference value at the current collection time point, and ΔP(t-Δt) representing the measured pressure difference value at the previous collection time point.

[0120] S430, performing comparison processing according to the first change amount and the second change amount to determine whether a particle trap removal failure occurs.

[0121] Specifically, the first change amount and the second change amount at each collection time point can be compared, and whether a particle trap removal failure occurs can be determined according to the comparison result.

[0122] Exemplarily, for any collection time, the first change amount and the second change amount of the collection time are compared, when the first change amount is less than the second change amount, it is determined that the particle trap removal may occur. The total number of comparisons of each collection time and the number of times of the particle trap removal in the diagnosis result are recorded, when the number of times of the particle trap removal reaches a preset number of times, or the ratio of the number of times of the particle trap removal to the total number of comparisons is greater than or equal to a preset ratio, it is determined that the particle trap removal fault occurs. The comparison results of the first change amount and the second change amount of each collection time are comprehensively used for fault diagnosis, which can avoid false alarm of fault and improve the accuracy of fault diagnosis.

[0123] It should be noted that, under normal circumstances, the measured pressure difference value is close to the model pressure difference value, and the difference between the two is small. When the particle trap removal occurs, the measured pressure difference value approaches 0. Similarly, under normal circumstances, the change amount of the measured pressure difference value and the model pressure difference value in a period of time is small, and when the particle trap removal occurs, the change amount of the measured pressure difference value becomes large.

[0124] In the optional embodiment, the first change amount of the measured pressure difference value and the second change amount of the model pressure difference value of each two adjacent collection times are calculated, and whether the particle trap removal fault occurs can be accurately diagnosed by comparing the first change amount and the second change amount.

[0125] Optionally, the comparison processing according to the first change amount and the second change amount to determine whether the particle trap removal fault occurs comprises:

[0126] S431, the first change amount is taken as a model pressure difference gradient of the current collection time, and the second change amount is taken as a measured pressure difference gradient of the current collection time.

[0127] Specifically, the first change amount is taken as a model pressure difference gradient x(t) of the current collection time, that is, x(t) = ΔPm(t) - ΔPm(t-Δt). The second change amount is taken as a measured pressure difference gradient y(t) of the current collection time, that is, y(t) = ΔP(t) - ΔP(t-Δt).

[0128] S432, according to the model pressure difference gradient of each collection time, a first function of the model pressure difference gradient with respect to time and a second function of the model pressure difference gradient with respect to a deviation time value are determined; according to the measured pressure difference gradient of each collection time, a third function of the measured pressure difference gradient with respect to the deviation time value is determined, wherein the deviation time value is the sum of the time and the time interval between adjacent two collection times, and the time interval between each adjacent two collection times is the same.

[0129] Specifically, the current collection time is any collection time, thus the first function of the model differential pressure gradient with respect to time is x(t), and the second function of the model differential pressure gradient with respect to the deviation time value can be x(t+Δt), and the third function of the measured differential pressure gradient with respect to the deviation time value is y(t+Δt), wherein the deviation time value is t+Δt, t represents any collection time, and Δt represents a time interval.

[0130] S433, multiplying the first function and the second function to obtain a model differential pressure function, and multiplying the first function and the third function to obtain a measured differential pressure function.

[0131] Specifically, the model differential pressure function can be represented as x(t)·x(t+Δt), and the measured differential pressure function can be represented as x(t)·y(t+Δt).

[0132] S434, integrating the model differential pressure function according to time within a preset time interval to obtain a model differential pressure integral value, and integrating the measured differential pressure function according to time to obtain a measured differential pressure integral value.

[0133] Specifically, within the preset time interval, the model differential pressure function x(t)·x(t+Δt) and the measured differential pressure function x(t)·y(t+Δt) are integrated respectively to obtain the model differential pressure integral value and the measured differential pressure integral value.

[0134] S435, determining the ratio between the measured differential pressure integral value and the model differential pressure integral value to obtain a differential pressure gradient correlation number.

[0135] Specifically, the ratio between the measured differential pressure integral value and the model differential pressure integral value is the differential pressure gradient correlation number.

[0136] S436, judging whether the differential pressure gradient correlation number is within a preset fault threshold range, and determining whether the particle trap removal fault occurs according to the judgment result.

[0137] Specifically, when the differential pressure gradient correlation number is within the preset fault threshold range, it is determined that the particle trap removal fault is likely to occur, and the preset fault threshold range can be 0.09 to 0.16.

[0138] In the optional embodiment, the measured differential pressure function can reflect the correlation between the model differential pressure gradient and the measured differential pressure gradient at adjacent two collection times, that is, the correlation between the second change amount of the model differential pressure value at the previous collection time and the first change amount of the measured differential pressure value at the current collection time, and the measured differential pressure function is integrated within a preset time interval to determine the cumulative value of each measured differential pressure function value, that is, the measured differential pressure integral value.

[0139] The model differential pressure function can reflect the mutual relationship between the model differential pressure gradient of two adjacent collection time points, i.e., the mutual relationship between the second change amount of the model differential pressure value at the previous collection time point and the second change amount of the model differential pressure value at the current collection time point. The model differential pressure function is integrated in a preset time interval to determine the cumulative value of each model differential pressure function value, i.e., the model differential pressure integral value.

[0140] The measured differential pressure integral value and the model differential pressure integral value can be compared to diagnose whether the particle trap removal fault occurs. Specifically, the model differential pressure integral value can be taken as a reference value, the ratio of the measured differential pressure integral value to the model differential pressure integral value is determined, and whether the ratio, i.e., the differential pressure gradient mutual relationship number, is within a preset fault threshold range is judged to diagnose whether the particle trap removal fault occurs. The fault diagnosis is performed by the cumulative value of the mutual relationship between the model differential pressure value change amount and the measured differential pressure value change amount in the preset time interval, which avoids the fault misreporting or missing reporting that may be caused by using single-time data for fault diagnosis, and improves the accuracy of the particle trap removal fault diagnosis.

[0141] Optionally, the determining whether the particle trap removal fault occurs according to the judgment result comprises:

[0142] When the differential pressure gradient mutual relationship number is within the preset fault threshold range, it is determined that the particle trap error occurs.

[0143] Specifically, whether the differential pressure gradient mutual relationship number is within the preset fault threshold range is judged. If yes, it is determined that the particle trap error occurs; if no, it is determined that the particle trap is normal, and the vehicle working condition data and the pipe measured pressure value collected by the pressure detection device are acquired, i.e., the vehicle working condition and the upstream and downstream pressures of the particle trap are continuously monitored.

[0144] When the number of times that the particle trap error occurs reaches a preset number limit value, it is determined that the particle trap removal fault occurs.

[0145] Specifically, whether the number of times that the particle trap error occurs reaches the preset number limit value is judged. If yes, it is determined that the particle trap removal fault occurs; if no, it is determined that the particle trap is normal at the current collection time point, and the vehicle working condition data and the pipe measured pressure value collected by the pressure detection device are acquired, i.e., the vehicle working condition and the upstream and downstream pressures of the particle trap are continuously monitored.

[0146] In the optional embodiment, the number of times that the particle trap error occurs is recorded over time, and when the number of times reaches the preset number limit value, it is determined that the particle trap removal fault occurs, which avoids the fault misreporting that may exist in a single particle trap error and improves the diagnosis accuracy of the particle trap removal fault.

[0147] The diagnostic process for the above-mentioned pipe detachment fault can be combined with the diagnostic process for the particulate trap removal fault to diagnose concurrent faults of particulate trap removal + upstream pipe detachment, as well as concurrent faults of particulate trap removal + downstream pipe detachment.

[0148] Specifically, vehicle operating data, upstream measured pressure value, and downstream measured pressure value are monitored to calculate the differential pressure gradient correlation coefficient, thereby determining whether a particulate filter error has occurred. When the number of particulate filter errors reaches a preset limit, a particulate filter removal fault is diagnosed.

[0149] At this point, the upstream energy ratio E1 and the downstream energy ratio E2 are calculated. Both are compared to preset thresholds. If the upstream energy ratio E1 is less than the preset threshold, an upstream pipeline error is identified; if the downstream energy ratio E2 is less than the preset threshold, a downstream pipeline error is identified. The number of comparisons between the upstream energy ratio E1 and the preset threshold, the number of upstream pipeline errors, the number of comparisons between the downstream energy ratio E2 and the preset threshold, and the number of downstream pipeline errors are recorded. When the ratio of the number of upstream errors to the number of comparisons is greater than a preset percentage threshold, a concurrent fault of particulate trap removal and upstream pipeline detachment is identified; when the ratio of the number of downstream errors to the number of comparisons is greater than a preset percentage threshold, a concurrent fault of particulate trap removal and downstream pipeline detachment is identified.

[0150] like Figure 5 The diagram shows the waveforms of various diagnostic data when a concurrent fault occurs (particulate filter removal + upstream pipeline detachment). Waveform 1 represents the engine load when the particulate filter is removed and the upstream pipeline is normal; waveform 2 represents the engine speed when the particulate filter is removed and the upstream pipeline is normal; waveform 3 represents the upstream pressure-energy ratio when the particulate filter is removed and the upstream pipeline is normal; waveform 4 represents the engine load when the particulate filter is removed and the upstream pipeline is detached; waveform 5 represents the engine speed when the particulate filter is removed and the upstream pipeline is detached; and waveform 6 represents the upstream pressure-energy ratio when the particulate filter is removed and the upstream pipeline is detached. It can be seen that when upstream pipeline detachment occurs, the upstream pressure-energy ratio decreases, approaching 0.

[0151] like Figure 6The diagram shows the waveforms of various diagnostic data when a concurrent fault occurs (particulate filter removal + downstream pipe detachment). Waveform 1 represents the engine load when the particulate filter is removed and the downstream pipe is normal; waveform 2 represents the engine speed when the particulate filter is removed and the downstream pipe is normal; waveform 3 represents the downstream pressure-energy ratio when the particulate filter is removed and the downstream pipe is normal; waveform 4 represents the engine load when the particulate filter is removed and the downstream pipe is detached; waveform 5 represents the engine speed when the particulate filter is removed and the downstream pipe is detached; and waveform 6 represents the downstream pressure-energy ratio when the particulate filter is removed and the downstream pipe is detached. It can be seen that when downstream pipe detachment occurs, the downstream pressure-energy ratio decreases, approaching 0.

[0152] In this embodiment, the preset percentage threshold can be set to 2%. As shown in Table 1, when the particulate filter is removed, the differential pressure cross-correlation coefficient is between 0.09 and 0.16; when the particulate filter is removed and the upstream pipeline is normal, the upstream energy ratio is between 0.12 and 0.34; when the particulate filter is removed and the upstream pipeline is disconnected, the upstream energy ratio is between 0 and 0.001; when the particulate filter is removed and the downstream pipeline is normal, the downstream energy ratio is equal to 1.63; when the particulate filter is removed and the downstream pipeline is disconnected, the downstream energy ratio is between 0.001 and 0.013.

[0153] Table 1. Diagnostic data for various concurrent failures related to GPF removal.

[0154]

[0155] like Figure 7 As shown in the figure, an embodiment of the present invention provides a fault diagnosis device for a particulate trap, based on a pressure detection device. One end of the pressure detection device is connected to the upstream of the particulate trap via an upstream pipeline, and the other end of the pressure detection device is connected to the downstream of the particulate trap via a downstream pipeline. The fault diagnosis device for the particulate trap includes:

[0156] The acquisition module is used to acquire vehicle operating condition data and the measured pressure value of the pipeline collected by the pressure detection device. The measured pressure value of the pipeline includes the upstream measured pressure value of the upstream pipeline and / or the downstream measured pressure value of the downstream pipeline.

[0157] The processing module is used to determine the pipeline model pressure value of the corresponding pipeline when the particulate filter is operating normally, based on the vehicle operating condition data.

[0158] The judgment module is used to compare the measured pressure value of the pipeline with the pressure value of the pipeline model to determine whether a pipeline detachment fault has occurred.

[0159] The fault diagnosis device of the particle trap of the embodiment is used to implement the fault diagnosis method of the particle trap as described above, and has the same advantages as the fault diagnosis method compared with the prior art, which will not be repeated here.

[0160] Optionally, the judging module is specifically configured to: determine a first pressure difference value between the pipeline actual measured pressure value and the atmospheric pressure, and a second pressure difference value between the pipeline model pressure value and the atmospheric pressure; determine a square of the first pressure difference value to obtain an actual measured pressure difference energy value; determine a square of the second pressure difference value to obtain a model pressure difference energy value; and compare the actual measured pressure difference energy value and the model pressure difference energy value to determine whether the pipeline shedding fault occurs.

[0161] Optionally, the judging module is specifically configured to: determine a ratio between the actual measured pressure difference energy value and the model pressure difference energy value to obtain an energy ratio value; compare the energy ratio value with a preset threshold value; and determine whether the pipeline shedding fault occurs according to a comparison result.

[0162] Optionally, the judging module is specifically configured to: determine that a pipeline error occurs when the energy ratio value is less than the preset threshold value; record a comparison frequency of the energy ratio value and the preset threshold value at different collection time points and an error frequency of the pipeline error; and determine that the pipeline shedding fault occurs when a ratio of the error frequency and the comparison frequency is greater than a preset percentage threshold value.

[0163] Optionally, the processing module is specifically configured to: determine the pipeline model pressure value corresponding to the vehicle working condition data in a preset corresponding relationship, the preset corresponding relationship including the vehicle working condition data and the corresponding pipeline model pressure value, and the pipeline model pressure value including an upstream model pressure value of the upstream pipeline and / or a downstream model pressure value of the downstream pipeline.

[0164] Optionally, the fault diagnosis device of the particle trap further includes:

[0165] The first calculating module is configured to determine actual measured pressure difference values between the upstream actual measured pressure value and the downstream actual measured pressure value at a plurality of continuous different collection time points, and model pressure difference values between the upstream model pressure value and the downstream model pressure value at each collection time point.

[0166] The second calculating module is configured to determine a first change amount between the model pressure difference value at a current collection time point and the model pressure difference value at a previous collection time point, and a second change amount between the actual measured pressure difference value at the current collection time point and the actual measured pressure difference value at a previous time point, the current collection time point being any one of the collection time points.

[0167] A comparison module is configured to compare the first variation and the second variation to determine whether the particle trap removal failure occurs.

[0168] Optionally, the comparison module is specifically configured to: take the first variation as a model differential pressure gradient at the current acquisition time, and take the second variation as a measured differential pressure gradient at the current acquisition time; determine a first function of the model differential pressure gradient with respect to time and a second function of the model differential pressure gradient with respect to a deviation time value according to the model differential pressure gradient at each acquisition time; determine a third function of the measured differential pressure gradient with respect to the deviation time value according to the measured differential pressure gradient at each acquisition time, wherein the deviation time value is a sum of the time and a time interval between adjacent two acquisition times, and the time interval between each adjacent two acquisition times is the same; multiply the first function and the second function to obtain a model differential pressure function; multiply the first function and the third function to obtain a measured differential pressure function; integrate the model differential pressure function according to time within a preset time interval to obtain a model differential pressure integral value; and integrate the measured differential pressure function according to time to obtain a measured differential pressure integral value; determine a ratio between the measured differential pressure integral value and the model differential pressure integral value to obtain a differential pressure gradient correlation number; and determine whether the particle trap removal failure occurs according to a result of determining whether the differential pressure gradient correlation number is within a preset failure threshold range.

[0169] Optionally, the comparison module is specifically configured to: determine that a particle trap error occurs when the differential pressure gradient correlation number is within the preset failure threshold range; and determine that the particle trap removal failure occurs when a number of times of the particle trap error reaching a preset number limit.

[0170] The embodiment of the present application provides a vehicle, which comprises a memory and a processor; the memory is used for storing a computer program; and the processor is used for implementing the fault diagnosis method of the particle trap when the computer program is executed.

[0171] The embodiment of the present application provides a computer readable storage medium, which stores a computer program; and when the computer program is executed by a processor, the fault diagnosis method of the particle trap is implemented.

[0172] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by a computer program instructing relevant hardware, and the program can be stored in a computer readable storage medium. When the program is executed, the program can include the processes of the above-mentioned embodiment methods. The storage medium can be a magnetic disc, an optical disc, a read-only memory (ROM), a random access memory (RAM), or the like. In this application, the units described as separate components can or can not be physically separated, and the components shown as units can or can not be physical units, that is, they can be located in one place, or they can be distributed on multiple network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the embodiment of the present application. In addition, the functional units in each embodiment of the present application can be integrated in one processing unit, or each unit can exist physically independently, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware or in the form of a software functional unit.

[0173] Although the present application is disclosed as above, the protection scope of the present application is not limited to this. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present application, and these changes and modifications will fall within the protection scope of the present application.

Claims

1. A fault diagnosis method for a particulate trap, characterized in that, Fault diagnosis of a particulate filter based on a pressure detection device, wherein one end of the pressure detection device is connected upstream of the particulate filter via an upstream pipeline, and the other end of the pressure detection device is connected downstream of the particulate filter via a downstream pipeline, the fault diagnosis method of the particulate filter includes: Acquire vehicle operating condition data and the measured pressure values ​​of the pipeline collected by the pressure detection device, wherein the measured pressure values ​​of the pipeline include the upstream measured pressure value of the upstream pipeline and / or the downstream measured pressure value of the downstream pipeline. The pipeline model pressure value of the corresponding pipeline when the particulate filter is operating normally is determined based on the vehicle operating condition data. The measured pressure value of the pipeline and the pressure value of the pipeline model are compared to determine whether a pipeline detachment fault has occurred. This includes: determining a first pressure difference between the measured pressure value of the pipeline and atmospheric pressure, and a second pressure difference between the pressure value of the pipeline model and atmospheric pressure; determining the square of the first pressure difference to obtain the measured pressure difference energy value; determining the square of the second pressure difference to obtain the model pressure difference energy value; and comparing the measured pressure difference energy value and the model pressure difference energy value to determine whether a pipeline detachment fault has occurred.

2. The fault diagnosis method for a particle trap according to claim 1, characterized in that, The step of comparing the measured differential pressure energy value and the model differential pressure energy value to determine whether the pipeline detachment fault has occurred includes: Determine the ratio between the measured differential pressure energy value and the model differential pressure energy value to obtain the energy ratio; The energy ratio is compared with a preset threshold, and the pipeline detachment fault is determined based on the comparison result.

3. The fault diagnosis method for a particle trap according to claim 2, characterized in that, The process of determining whether a pipe detachment fault has occurred based on the comparison results includes: When the energy ratio is less than a preset threshold, a pipeline error is determined to have occurred. Record the number of times the energy ratio is compared with the preset threshold at different acquisition times, as well as the number of times the pipeline error occurs; When the ratio of the number of errors to the number of comparisons is greater than a preset percentage threshold, it is determined that the pipeline detachment fault has occurred.

4. The fault diagnosis method for a particulate trap according to any one of claims 1 to 3, characterized in that, The step of determining the pipeline model pressure value of the corresponding pipeline when the particulate filter is operating normally based on the vehicle operating condition data includes: The pipeline model pressure value corresponding to the vehicle operating condition data is determined in a preset correspondence relationship. The preset correspondence relationship includes the vehicle operating condition data and the corresponding pipeline model pressure value. The pipeline model pressure value includes the upstream model pressure value of the upstream pipeline and / or the downstream model pressure value of the downstream pipeline.

5. The fault diagnosis method for a particulate trap according to any one of claims 1 to 3, characterized in that, Also includes: Determine the measured pressure difference between the upstream measured pressure value and the downstream measured pressure value at multiple consecutive different acquisition times, and the model pressure difference between the upstream model pressure value and the downstream model pressure value at each acquisition time. The pipeline model pressure value includes the upstream model pressure value of the upstream pipeline and the downstream model pressure value of the downstream pipeline. Determine a first change between the model pressure difference value at the current acquisition time and the model pressure difference value at the previous acquisition time, and a second change between the measured pressure difference value at the current acquisition time and the measured pressure difference value at the previous time, wherein the current acquisition time is any acquisition time; The first change and the second change are compared to determine whether a particle trap removal failure has occurred.

6. The fault diagnosis method for a particle trap according to claim 5, characterized in that, The step of comparing the first change and the second change to determine whether a particle trap removal failure has occurred includes: The first change is used as the model differential pressure gradient at the current acquisition time, and the second change is used as the measured differential pressure gradient at the current acquisition time. The model pressure gradient is determined as a first function of time based on the model pressure gradient at each acquisition time, and as a second function of the model pressure gradient with respect to the deviation time value; the measured pressure gradient is determined as a third function of the measured pressure gradient with respect to the deviation time value based on the measured pressure gradient at each acquisition time, wherein the deviation time value is the sum of the time and the time interval between two adjacent acquisition times, and the time interval between each pair of adjacent acquisition times is the same; Multiplying the first function by the second function yields the model pressure difference function; multiplying the first function by the third function yields the measured pressure difference function. Within a preset time interval, the model pressure difference function is integrated over time to obtain the model pressure difference integral value; and the measured pressure difference function is integrated over time to obtain the measured pressure difference integral value. The ratio between the measured integral value of differential pressure and the integral value of differential pressure in the model is determined to obtain the cross-correlation coefficient of differential pressure gradient. Determine whether the differential pressure gradient cross-correlation coefficient is within the preset fault threshold range, and determine whether the particle trap removal fault has occurred based on the determination result.

7. The fault diagnosis method for a particle trap according to claim 6, characterized in that, The step of determining whether a particle trap removal failure has occurred based on the judgment result includes: When the differential pressure gradient cross-correlation coefficient is within the preset fault threshold range, a particle trap error is determined to have occurred. When the number of times the particle catcher error occurs reaches a preset limit, a particle catcher removal failure is determined to have occurred.

8. A fault diagnosis device for a particulate trap, characterized in that, Fault diagnosis of the particulate trap is performed based on a pressure detection device. One end of the pressure detection device is connected upstream of the particulate trap via an upstream pipeline, and the other end of the pressure detection device is connected downstream of the particulate trap via a downstream pipeline. The fault diagnosis device for the particulate trap includes: The acquisition module is used to acquire vehicle operating condition data and the measured pressure value of the pipeline collected by the pressure detection device. The measured pressure value of the pipeline includes the upstream measured pressure value of the upstream pipeline and / or the downstream measured pressure value of the downstream pipeline. The processing module is used to determine the pipeline model pressure value of the corresponding pipeline when the particulate filter is operating normally, based on the vehicle operating condition data. The judgment module is used to compare the measured pressure value of the pipeline with the pressure value of the pipeline model to determine whether a pipeline detachment fault has occurred. The judgment module is specifically used to: determine the first pressure difference between the measured pressure value of the pipeline and atmospheric pressure, and the second pressure difference between the model pressure value of the pipeline and atmospheric pressure; determine the square of the first pressure difference to obtain the measured pressure difference energy value; determine the square of the second pressure difference to obtain the model pressure difference energy value; compare the measured pressure difference energy value and the model pressure difference energy value to determine whether the pipeline detachment fault has occurred.

9. A vehicle, characterized in that, Including memory and processor; The memory is used to store computer programs; The processor is configured to implement, when executing the computer program, the fault diagnosis method for the particle trap as described in any one of claims 1 to 7.

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