Particle trap diagnosis method and device, vehicle, storage medium and computer program product

Abstract

The invention provides a particle trap diagnosis method and device, a vehicle, a storage medium and a computer program product. The particle trap diagnosis method comprises the steps that the vehicle operation condition is detected; when the vehicle operation working condition is the cold start working condition, the temperature value of the downstream of the particulate filter is detected through a temperature sensor on the downstream of the particulate filter; determining the downstream temperature change rate of the particulate filter according to the temperature value; and when the temperature change rate is not in a preset temperature change rate range, determining that the particle trap is lost. The running working condition of a vehicle is detected, under the cold start working condition, the temperature value of the downstream of the particulate filter is detected, whether the particulate filter is lost or not is judged according to the temperature change rate of the temperature value of the downstream of the particulate filter, and then under the condition that a differential pressure sensor cannot work normally under the cold start working condition, the particulate filter is lost. And whether the particle trap is lost or not is diagnosed.

Description

Technical Field

[0001] The present invention relates to the field of vehicle technology, and in particular to a particle trap diagnosis method, device, vehicle, storage medium and computer program product. Background Art

[0002] With the tightening of emission regulations, the new emission regulations have stricter requirements for the diagnosis of gasoline particulate filters. The gasoline particulate filter removal diagnosis needs to detect an environment above -10 degrees. Traditional gasoline particulate filter diagnosis is all differential pressure sensor diagnosis, which can not only monitor the carbon accumulation, but also monitor the removal diagnosis.

[0003] However, in low temperature environments, the differential pressure tube is prone to ice, which will affect the diagnosis of the particulate filter. Especially in the combination of non-tight-coupled particulate filters and hybrid vehicles, the differential pressure tube may be frozen for a long time and unable to output a formal signal, resulting in an inability to accurately detect whether the particulate filter is lost.

[0004] The above contents are only used to assist in understanding the technical solution of the present invention and do not constitute an admission that the above contents are prior art. Summary of the invention

[0005] The main purpose of the present invention is to provide a particulate filter diagnosis method, device, vehicle, storage medium and computer program product, aiming to solve the technical problem in the prior art that the particulate filter cannot be detected when the pressure difference sensor is frozen.

[0006] To achieve the above object, the present invention proposes a particle trap diagnosis method, the particle trap diagnosis method comprising:

[0007] Detect vehicle operating conditions;

[0008] determining a rate of change of temperature downstream of the particulate trap based on the temperature value;

[0009] When the temperature change rate is not within a preset temperature change rate range, it is determined that the particulate trap is lost.

[0010] Optionally, after detecting the temperature value downstream of the particulate trap by a temperature sensor downstream of the particulate trap, the method further comprises:

[0011] Recording the engine start time and obtaining a first initial temperature through a downstream temperature sensor;

[0012] When the startup time is greater than a preset time threshold, obtaining a first current temperature through a downstream temperature sensor;

[0013] determining a temperature increment according to the first current temperature and the first initial temperature;

[0014] When the temperature increment is not within a preset temperature increment range, it is determined that the particulate trap is lost.

[0015] Optionally, when the startup time is greater than a preset time threshold, after obtaining the current temperature through a downstream temperature sensor, the method further includes:

[0016] Determine a temperature area according to the first current temperature, the first initial temperature and a preset time threshold;

[0017] When the temperature area is not within the preset temperature area range, it is determined that the particulate trap is lost.

[0018] Optionally, the detecting the vehicle operating condition includes:

[0019] Detecting the current ambient temperature of the vehicle, the current operating state, and the duration of the current operating state;

[0020] When the ambient temperature is lower than a preset temperature threshold, the current operating state is an ignition-off state and the duration is greater than a preset duration, the vehicle operating condition is determined to be a cold start condition.

[0021] Optionally, when the vehicle operating condition is a cold start condition, after detecting the temperature value downstream of the particulate trap by a temperature sensor downstream of the particulate trap, the method further includes:

[0022] When the temperature change rate is within a preset temperature change rate range, obtaining a second initial temperature through the downstream temperature sensor;

[0023] When the second initial temperature reaches a preset complete warming temperature, detecting a vehicle operating condition;

[0024] When the vehicle operating condition is a deceleration condition, recording the deceleration time of the deceleration condition;

[0025] When the deceleration time reaches a preset deceleration time threshold, obtaining a second current temperature through a downstream temperature sensor;

[0026] determining a temperature drop downstream of the particle trap according to the second initial temperature and the second current temperature;

[0027] When the temperature drop reaches a preset temperature drop range, it is determined that the particulate trap is lost.

[0028] Optionally, after determining the temperature drop downstream of the particle trap according to the second initial temperature and the second current temperature, the method further includes:

[0029] When the temperature drop reaches the preset temperature drop range, recording a first number of times the temperature drop reaches the preset temperature drop range and a second number of times the vehicle operating condition is in a deceleration condition, and returning to the step of detecting the vehicle operating condition;

[0030] When the second number reaches a preset number of deceleration times, obtaining a ratio of the first number to the second number;

[0031] When the ratio reaches a preset ratio, it is determined that the particulate trap is lost.

[0032] In addition, in order to achieve the above-mentioned object, the present invention also provides a particle trap diagnostic device, the particle trap diagnostic device comprising:

[0033] A working condition detection module, used to detect the vehicle operating condition;

[0034] a temperature detection module, used for detecting a temperature value downstream of the particulate trap by a temperature sensor downstream of the particulate trap when the vehicle is in a cold start condition;

[0035] a temperature processing module, configured to determine a temperature change rate downstream of the particle trap according to the temperature value;

[0036] The result determination module is used to determine that the particulate trap is lost when the temperature change rate is not within a preset temperature change rate range.

[0037] In addition, to achieve the above-mentioned purpose, the present invention also provides a vehicle, which includes: a memory, a processor, and a particulate filter diagnostic program stored in the memory and executable on the processor, and the particulate filter diagnostic program implements the steps of the particulate filter diagnostic method as described when executed by the processor.

[0038] In addition, to achieve the above-mentioned purpose, the present invention further provides a storage medium, on which a particulate trap diagnostic program is stored, and when the particulate trap diagnostic program is executed by a processor, the steps of the particulate trap diagnostic method are implemented.

[0039] In addition, to achieve the above-mentioned purpose, the present invention also provides a computer program product, wherein the computer program product includes a computer program, and when the computer program is executed by a processor, the steps of the particulate filter diagnostic method are implemented.

[0040] The present invention provides a particle trap diagnosis method, device, vehicle, storage medium and computer program product. The particle trap diagnosis method includes: detecting the vehicle operating condition; when the vehicle operating condition is a cold start condition, detecting the temperature value downstream of the particle trap by a temperature sensor downstream of the particle trap; determining the temperature change rate downstream of the particle trap according to the temperature value; and determining that the particle trap is lost when the temperature change rate is not within a preset temperature change rate range. By detecting the vehicle operating condition, under the cold start condition, by detecting the temperature value downstream of the particle trap, and judging whether the particle trap is lost according to the temperature change rate of the temperature value downstream of the particle trap, it is realized that when the pressure difference sensor cannot work normally under the cold start condition, whether the particle trap is lost can be diagnosed. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0042] Figure 1 A schematic diagram of the structure of a vehicle involved in an embodiment of the present invention;

[0043] Figure 2 A first flow chart of a first embodiment of the particle trap diagnostic method proposed by the invention;

[0044] Figure 3 A second flow chart of the first embodiment of the particle trap diagnostic method proposed by the invention;

[0045] Figure 4 A first flow chart of a second embodiment of the particle trap diagnostic method proposed by the invention;

[0046] Figure 5 A second flow chart of the second embodiment of the particulate filter diagnostic method proposed by the invention;

[0047] Figure 6 A first flow chart of a third embodiment of the particle trap diagnostic method proposed by the invention;

[0048] Figure 7 A second flow chart of the third embodiment of the particulate filter diagnostic method proposed by the invention;

[0049] Figure 8 This is a schematic diagram of the module structure of the particulate filter diagnostic device according to an embodiment of the present application.

[0050] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0051] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0052] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0053] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0054] In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0055] Reference Figure 1 , Figure 1 The figure is a schematic diagram of the structure of a vehicle involved in an embodiment of the present invention.

[0056] like Figure 1As shown, the vehicle may include: a processor 1001, such as a central processing unit (CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. Among them, the communication bus 1002 is used to realize the connection and communication between these components. The user interface 1003 may include a display screen (Display), and the user interface 1003 may also include a standard wired interface and a wireless interface. The wired interface of the user interface 1003 may be a USB interface in the present invention. The network interface 1004 may optionally include a standard wired interface and a wireless interface (such as a wireless fidelity (Wireless-Fidelity, WI-FI) interface). The memory 1005 may be a high-speed random access memory (Random Access Memory, RAM) or a stable memory (Non-volatile Memory, NVM), such as a disk memory. The memory 1005 may also be a storage device independent of the aforementioned processor 1001.

[0057] Those skilled in the art will understand that Figure 1 The structure shown in the figure does not constitute a limitation on the vehicle, and may include more or less components than shown in the figure, or combine certain components, or arrange the components differently.

[0058] like Figure 1 As shown, the memory 1005 identified as a computer storage medium may include an operating system, a network communication module, a user interface module, and a particle trap diagnostic program.

[0059] exist Figure 1 In the vehicle shown, the network interface 1004 is mainly used to connect to the background server and communicate data with the background server; the user interface 1003 is mainly used to connect to the user device; the vehicle calls the particulate filter diagnostic program stored in the memory 1005 through the processor 1001, and executes the particulate filter diagnostic method provided by the embodiment of the present invention.

[0060] Based on the above vehicle structure, a first embodiment of the particulate trap diagnosis method of the present invention is proposed. Figure 2 , Figure 2 This is a first flow chart of the first embodiment of the particulate filter diagnosis method proposed by the invention.

[0061] In this embodiment, the particle trap diagnosis method includes:

[0062] Step S10: Detect vehicle operating conditions.

[0063] It should be understood that the execution subject in the present application can be a controller arranged inside the vehicle, which can be a body controller. The controller can establish a connection with a temperature sensor arranged downstream of the particulate filter, and when determining the vehicle status, the controller can diagnose whether the particulate filter is lost based on the temperature value collected by the temperature sensor and the temperature value.

[0064] It is understood that the particle trap is installed in the vehicle exhaust system to capture particulate matter in the vehicle exhaust that does not meet the emission standards to prevent the particulate matter from being released into the atmosphere. If the particle trap is lost, the particulate matter will enter the atmosphere, causing environmental impact.

[0065] It should be noted that the vehicle operating condition refers to the current operating state of the vehicle, which may be a cold start condition, a hot start condition, a flameout condition, etc. The temperature in the vehicle exhaust system corresponding to different vehicle operating conditions will also vary.

[0066] In a specific implementation, the controller can be directly used to detect the parameters with different parameter values ​​under different operating conditions of the vehicle, and then determine the working condition of the vehicle. For example, the vehicle power-on state, the working state of the vehicle's engine and motor, the shutdown time of the abnormal electrical load in the vehicle, etc.

[0067] Step S20: When the vehicle operating condition is a cold start condition, a temperature value downstream of the particulate trap is detected in real time by a temperature sensor downstream of the particulate trap.

[0068] It is understandable that under different vehicle operating conditions, the temperature values ​​in the vehicle exhaust emission system will vary to a certain extent, and under the same vehicle operating conditions, the temperature values ​​in the vehicle exhaust emission system will also vary. Different components in the vehicle exhaust emission system will also affect the temperature in the vehicle exhaust emission system.

[0069] It should be noted that the downstream of the particulate filter refers to the position behind the particulate filter in the direction of exhaust emission. The temperature sensor is arranged at the downstream position of the particulate filter in the vehicle exhaust emission system, and can collect the temperature value downstream of the particulate filter in real time.

[0070] Step S30: determining the temperature change rate downstream of the particulate trap according to the temperature value.

[0071] It can be understood that the temperature change rate refers to the temperature change in the vehicle's exhaust system at the downstream of the particulate filter. Under cold start conditions, the temperature in the vehicle's exhaust system changes from the ambient temperature at the beginning to the exhaust temperature, and the temperature change value is relatively obvious. In the case of the presence of a particulate filter, due to the heat capacity of the particulate filter, the particulate filter will absorb part of the heat in the startup state, causing the temperature downstream of the particulate filter in the vehicle's exhaust system to rise slowly; in the case of the particulate filter being lost, the temperature downstream of the particulate filter in the vehicle's exhaust system rises relatively quickly because there is no particulate filter to absorb heat.

[0072] It should be understood that, when the temperature value is collected in real time by the temperature sensor downstream of the particulate trap, all the temperature values ​​collected under the vehicle cold start condition may be processed to obtain the temperature change rate downstream of the particulate trap.

[0073] Step S40: When the temperature change rate is not within a preset temperature change rate range, it is determined that the particulate trap is lost.

[0074] It can be understood that the preset temperature change rate range refers to a preset temperature change rate range, which is the temperature change rate range downstream of the particulate filter in the vehicle exhaust emission system when the particulate filter is not lost.

[0075] In a specific implementation, the temperature change rate downstream of the particulate filter under cold start conditions can be compared with the endpoint value of a preset temperature change rate range. When it is determined that the temperature change rate downstream of the particulate filter is within the preset temperature change rate range, it can be determined that the particulate filter is not lost; similarly, when the temperature change rate downstream of the particulate filter is not within the preset temperature change rate range, it can be determined that the particulate filter is lost.

[0076] In this embodiment, a particle trap diagnosis method is provided, and the particle trap diagnosis method includes: detecting a vehicle operating condition; when the vehicle operating condition is a cold start condition, detecting a temperature value downstream of the particle trap by a temperature sensor downstream of the particle trap; determining a temperature change rate downstream of the particle trap according to the temperature value; and determining that the particle trap is lost when the temperature change rate is not within a preset temperature change rate range. By detecting the vehicle operating condition, under a cold start condition, by detecting a temperature value downstream of the particle trap, and judging whether the particle trap is lost according to a temperature change rate of the temperature value downstream of the particle trap, it is possible to diagnose whether the particle trap is lost when the pressure difference sensor cannot work normally under a cold start condition.

[0077] Further, see Figure 3 , Figure 3This is a second flow chart of the first embodiment of the particulate filter diagnosis method proposed by the invention.

[0078] exist Figure 3 In the step S10, the step S10 comprises:

[0079] Step S101: Detect the current ambient temperature of the vehicle, the current operating state, and the duration of the current operating state.

[0080] It should be understood that when the vehicle is in a cold start condition, the temperature change downstream of the particulate filter in the vehicle exhaust emission system is more obvious. In order to accurately detect whether the particulate filter is lost, it is necessary to accurately detect whether the vehicle is in a cold start condition.

[0081] It should be noted that the ambient temperature refers to the temperature value in the environment where the vehicle is located. When the ambient temperature is low, it can be determined that the vehicle is in a low temperature environment. Taking into account that the ambient temperature may change, the ambient temperature of the vehicle's current environment can be collected in real time to avoid inaccurate judgment of the vehicle's operating conditions due to changes in ambient temperature. The current operating state refers to the working state of the vehicle at the current moment. The current operating state may include the flameout state, driving state, power-on state, etc. In order to determine whether the vehicle is cold started, it is also necessary to determine the length of time the vehicle is in the flameout state. For example, when the vehicle has just switched from the driving state to the flameout state, the temperature in the vehicle's exhaust emission system and the engine water temperature have not cooled to the ambient temperature. In this case, directly using the ambient temperature and the current operating state of the vehicle cannot determine whether the vehicle's operating condition is a cold start condition.

[0082] In a specific implementation, the ambient temperature of the vehicle's current environment can be collected in real time through sensors installed on the vehicle body, and the current operating state of the vehicle can be detected according to the operating state of the abnormal electrical load inside the vehicle, and the duration of the vehicle in the current operating state can be recorded. During the process of detecting the duration, if the current operating condition of the vehicle changes, the duration of the current operating state of the vehicle is re-timed.

[0083] Step S102: When the ambient temperature is lower than a preset temperature threshold, the current operating state is an ignition-off state and the duration is greater than a preset duration, the vehicle operating condition is determined to be a cold start condition.

[0084] It should be noted that the preset temperature threshold is a pre-set temperature threshold for determining whether the vehicle is cold-started, and the temperature value of the preset temperature threshold is usually lower than the engine water temperature when the engine is working normally. When the engine is in the off state and the duration is greater than the preset duration, the engine water temperature in the vehicle is the normal ambient temperature. There needs to be a large difference between the preset temperature threshold and the driving temperature of the vehicle during normal driving. The off state is a state where the vehicle is stopped and the engine is turned off and the power is off. The preset duration is a pre-set duration to ensure that the vehicle is completely stable in the current operating state. When the vehicle is in the off state, the duration is the vehicle immersion duration, which can be set to 8 hours.

[0085] It is understandable that when it is confirmed that the current ambient temperature of the vehicle is lower than the preset temperature threshold, the vehicle is in an off state and the duration of the off state reaches a preset duration, the vehicle startup state at this time can be determined to be a cold start state, thereby avoiding interference caused by inaccurate startup state and achieving more accurate diagnosis of the particulate filter in the cold start state. The identification of the cold start condition is mainly based on the difference between the water temperature of the normal operation of the engine and the ambient temperature. When the difference between the two is small, the vehicle operating condition can be determined to be a cold start condition. When the current operating state of the vehicle is the off state and the duration of the off state is greater than the preset time, it can be determined that the engine water temperature is the same as the ambient temperature, and then when the ambient temperature is lower than the preset temperature threshold, the vehicle operating condition can be determined to be a cold start condition.

[0086] In addition, considering the use standards of the particulate filter, when the ambient temperature is too low, there is no specific limitation on the working state of the particulate filter. For example, when the ambient temperature is below minus ten degrees Celsius, there is no need to diagnose whether the particulate filter exists.

[0087] Based on the above first embodiment, a second embodiment of the particle trap diagnosis method of the present invention is proposed. Figure 4 , Figure 4 This is a first flow chart of the second embodiment of the particulate filter diagnosis method proposed by the invention.

[0088] In this embodiment, after step S20, the following steps are further included:

[0089] Step S201: Record the engine start time and obtain a first initial temperature through a downstream temperature sensor.

[0090] It should be understood that the engine start time refers to the time the vehicle runs when the vehicle switches from a cold start state to a running state. The first initial temperature is the temperature value downstream of the particulate filter in the vehicle exhaust emission system when the vehicle switches from a cold start state to a running state.

[0091] It should be noted that in the case of a cold start of the vehicle, the temperature value downstream of the particulate filter will continue to change for a period of time after the vehicle is started. After the engine has been started for a certain period of time, the exhaust gas emission will gradually cause the temperature value downstream of the particulate filter to reach the temperature value of the vehicle under normal driving conditions. Considering that regardless of whether the particulate filter is lost, the temperature value downstream of the particulate filter will eventually reach the corresponding temperature value of the vehicle under normal driving conditions, in order to diagnose the particulate filter more accurately, it is necessary to diagnose whether the particulate filter is lost within a period of time after the vehicle is started.

[0092] In a specific implementation, when the vehicle is cold started, when the temperature sensor detects the temperature downstream of the particulate trap, the temperature value of the temperature sensor at the time of executing the vehicle cold start can be recorded as the first initial temperature, and then the engine start time can be recorded.

[0093] Step S202: when the startup time is greater than a preset time threshold, obtaining a first current temperature through a downstream temperature sensor.

[0094] It should be noted that the preset time threshold is the time threshold for the vehicle to maintain a cold start, and the preset time threshold can effectively avoid the situation where the vehicle is started by mistake or for a short time, which affects the diagnosis of whether the particulate trap is lost. For example, when the vehicle is in a cold start state, after only 5 seconds of starting, the vehicle performs the process of shutting down. During the 5 seconds, the particulate trap in the vehicle may not be started, so the diagnosis of whether the particulate trap is lost during the 5 seconds is not accurate.

[0095] Therefore, in a specific implementation, the start time of the engine may be recorded in real time, and when the start time reaches a preset time threshold, the temperature value downstream of the particulate trap collected by the temperature sensor is recorded again as the first current temperature.

[0096] Step S203: determining a temperature increment according to the first current temperature and the first initial temperature.

[0097] It is understandable that during the cold start of the vehicle, whether there is a particulate trap in the vehicle exhaust system has a great influence on the temperature within the preset time threshold. For example, in the case of a particulate trap, the temperature downstream of the particulate trap may increase by only 20 to 30 degrees Celsius within the preset time threshold, while in the case of a particulate trap being lost, the temperature downstream of the particulate trap in the vehicle exhaust system may increase by 50 to 100 degrees Celsius within the preset time threshold. Therefore, in this embodiment, it is also possible to confirm whether the particulate trap is lost based on the temperature increment within the preset time threshold.

[0098] In a specific implementation, the temperature increment downstream of the particulate trap within the preset time threshold may be determined according to a first initial temperature at the time of cold start of the vehicle and a first current temperature when the engine starts and reaches the preset time threshold.

[0099] Step S204: when the temperature increment is not within the preset temperature increment range, it is determined that the particulate trap is lost.

[0100] It can be understood that the preset temperature increment range is the temperature increment range of the particulate trap downstream when the engine starts and reaches the preset time threshold when the temperature increment is determined within the preset time threshold, if the particulate trap is not lost. When the temperature increment is detected within the preset time threshold and is within the preset temperature increment range, it can be determined that the particulate trap is not lost; and when the temperature increment is detected within the preset time threshold and is not within the preset temperature increment range, it can be determined that the particulate trap is lost.

[0101] Reference Figure 5 , Figure 5 This is a second flow chart of the second embodiment of the particle trap diagnosis method proposed in the invention. After step S202, it also includes:

[0102] Step S205: determining a temperature area according to the first current temperature, the first initial temperature and a preset time threshold.

[0103] It should be noted that the temperature area is the integrated change value of the temperature within a unit area downstream of the particle trap within a preset time. The temperature area is the integral of the temperature change value and the temperature change time.

[0104] It is understandable that whether the particulate trap is lost will determine the temperature change rate in the vehicle exhaust system, so whether the particulate trap is lost will also affect the temperature area. Therefore, in this embodiment, whether the particulate trap is lost can also be diagnosed by the temperature area downstream of the particulate trap.

[0105] Step S206: When the temperature area is not within the preset temperature area range, it is determined that the particulate trap is lost.

[0106] It should be noted that the preset temperature area range is the range of the temperature area change of the particulate trap downstream when the engine starts and reaches the preset time threshold, if the particulate trap is not lost. When the temperature area is detected to be within the preset temperature area range within the preset time threshold, it can be determined that the particulate trap is not lost; and when the temperature area is detected not to be within the preset temperature area range within the preset time threshold, it can be determined that the particulate trap is lost.

[0107] In this embodiment, by limiting the engine start time, whether the temperature increment or the change of the temperature area within the preset time threshold satisfies the preset time threshold range or the preset temperature area range corresponding to the condition that the particulate filter is not lost, and then under the condition of obtaining different temperature parameters, it is possible to accurately diagnose whether the particulate filter is lost.

[0108] Based on the first embodiment or the second embodiment, a third embodiment of the particle trap diagnosis method of the present invention is proposed. Figure 6 , Figure 6 This is a first flow chart of the third embodiment of the particulate filter diagnosis method proposed by the invention.

[0109] In this embodiment, after step S20, the following steps are further included:

[0110] Step S21: when the temperature change rate is within a preset temperature change rate range, obtaining a second initial temperature through the downstream temperature sensor.

[0111] It should be understood that when the vehicle is in a driving state, the temperature value in the vehicle exhaust emission system will be stable within a certain range, and there will be no significant temperature change downstream of the particulate trap whether the particulate trap is lost. That is, the difference in temperature change downstream of the particulate trap is not obvious in the two states of the particulate trap being lost or the particulate trap being in stable operation. However, when the vehicle is in a deceleration condition, the microparticles in the exhaust gas in the vehicle change. At this time, the carbon powder in the captured microparticles will be further burned inside the particulate trap, and because the heat generated inside the engine is reduced under the deceleration condition, the heat capacity of the particulate trap will cause the particulate trap to release a certain amount of heat. At this time, whether the particulate trap is lost will have a large temperature difference downstream of the particulate trap. Under the deceleration condition, if the particulate trap is not lost, the temperature change downstream of the particulate trap is small; if the particulate trap is lost, the temperature change downstream of the particulate trap is large. Therefore, it is also possible to diagnose whether the particulate trap is lost when the vehicle is in a deceleration state.

[0112] In specific diagnosis, it is necessary to determine whether the particulate trap is lost based on the temperature change, so it is necessary to determine the temperature change value under the vehicle deceleration condition. The preset temperature range is the temperature value range downstream of the particulate trap during normal driving of the vehicle. When the temperature change rate is within the preset temperature change rate range, it can be determined that the particulate trap is not lost during the vehicle startup process. At this time, it is necessary to detect the temperature value downstream of the particulate trap in real time to determine whether the particulate trap has reached a normal working state.

[0113] Step S22: When the second initial temperature reaches a preset warm-up temperature, the vehicle operating condition is detected.

[0114] It should be noted that the preset warm-up temperature is a temperature preset to determine whether the vehicle is in normal operation. The preset warm-up temperature can be set to 400 degrees Celsius. When the second initial temperature reaches the preset warm-up temperature, it can be determined that the vehicle is in normal operation.

[0115] It should be understood that when the vehicle is in a deceleration condition, it is possible to diagnose whether the particulate filter is lost. Therefore, when the second initial temperature reaches the preset warm-up temperature, the vehicle operating condition can be detected in real time to confirm whether the vehicle operating condition is a deceleration condition. In the specific detection process, it can be determined whether the vehicle operating condition is a deceleration condition in combination with the vehicle's throttle opening or the vehicle speed sensor in the vehicle.

[0116] Step S23: When the vehicle operating condition is a deceleration condition, the deceleration duration of the deceleration condition is recorded.

[0117] It is understandable that when the vehicle is in a deceleration condition, the microparticles in the exhaust gas inside the vehicle change. At this time, the carbon powder in the captured microparticles will be further burned inside the particulate collector, and because the heat generated inside the engine is reduced under the deceleration condition, the thermal capacity of the particulate collector will cause the particulate collector to release a certain amount of heat. At this time, whether the particulate collector is lost will cause a certain temperature difference downstream of the particulate collector. However, deceleration in a short period of time may not cause a temperature difference downstream of the particulate collector, such as the vehicle's braking process. In order to more accurately diagnose whether the particulate collector is lost, the deceleration time of the deceleration condition can be recorded. When the deceleration time of the deceleration condition is very short, it is determined that the current deceleration condition of the vehicle has failed, and the step of detecting the vehicle's operating condition is re-executed.

[0118] Step S24: when the deceleration time reaches a preset deceleration time threshold, a second current temperature is acquired through a downstream temperature sensor.

[0119] It can be understood that the preset deceleration time threshold is a time threshold pre-set to determine whether the deceleration process will cause a temperature difference downstream of the particulate trap. When the deceleration time reaches the preset deceleration time threshold, it can be determined that the deceleration condition of the vehicle is valid, and the second current temperature downstream of the particulate trap can be obtained through the temperature sensor. The second current temperature is the temperature value downstream of the particulate trap when the deceleration time reaches the preset deceleration time threshold.

[0120] Step S25: determining the temperature drop downstream of the particulate trap according to the second initial temperature and the second current temperature.

[0121] It should be understood that when the vehicle is in a deceleration condition and there is a particulate filter, the heat capacity of the particulate filter will release part of the energy and the microparticles in the particulate filter will burn, which will have a certain compensation effect on the heat output of the engine, resulting in a relatively small temperature change downstream of the particulate filter; when the vehicle is in a deceleration condition, but there is no particulate filter, there is no heat capacity effect to release energy and the microparticles in the particulate filter will burn, resulting in a relatively large temperature change range for the temperature downstream of the particulate filter.

[0122] It should be noted that the temperature drop refers to the temperature change that occurs downstream of the particulate filter within the preset deceleration time threshold under the vehicle deceleration condition. The temperature drop can be directly obtained by taking the difference between the second initial temperature and the second current temperature. The second initial temperature is the temperature when the vehicle is operating normally, and the specific value of the second temperature changes with the operation of the vehicle. When the second initial temperature reaches the preset warm-up temperature range, it can be determined that the vehicle is operating normally; however, when determining the temperature drop downstream of the deceleration process, the second initial temperature is the temperature corresponding to the moment when the vehicle starts to decelerate.

[0123] Step S26: When the temperature drop reaches a preset temperature drop range, it is determined that the particulate trap is lost.

[0124] It can be understood that the preset temperature drop range is the range of temperature change downstream of the particulate trap within the preset deceleration time threshold when the particulate trap is lost. When the temperature drop within the preset deceleration time threshold is within the preset temperature drop range, it can be determined that the particulate trap is lost; when the temperature drop within the preset deceleration time threshold does not reach the preset temperature drop range, it can be determined that the particulate trap is not lost.

[0125] Reference Figure 7 , Figure 7 This is a second flow chart of the third embodiment of the particle trap diagnostic method proposed in the invention. After step S25, it also includes:

[0126] Step S27: When the temperature drop reaches the preset temperature drop range, record the first number of times the temperature drop reaches the preset temperature drop range and the second number of times the vehicle operating condition is in a deceleration condition, and return to the step of detecting the vehicle operating condition.

[0127] It should be understood that the result of diagnosing whether the particulate trap is lost under deceleration conditions may be somewhat accidental, considering that there may be many deceleration conditions during driving, such as a road section with many traffic lights. In this case, the result of diagnosing whether the particulate trap is lost under deceleration conditions for multiple times can be used to more accurately diagnose whether the particulate trap is lost.

[0128] It should be noted that the first number is the number of times the temperature drop reaches the preset temperature drop range, that is, the number of times the particulate trap loss is diagnosed. The second number is the number of valid deceleration conditions, that is, the number of times the deceleration time reaches the preset deceleration time threshold.

[0129] In a specific implementation, when the temperature drop reaches the preset temperature drop range, the temperature drop can be recorded once, that is, the number of times the particle trap is lost can be recorded. When the vehicle decelerates and the deceleration time reaches the preset deceleration time threshold, it is recorded once until the second number is obtained.

[0130] Step S28: when the second number reaches a preset number of deceleration times, obtaining a ratio of the first number to the second number.

[0131] It should be understood that the preset deceleration times are the pre-set deceleration times for avoiding accidental diagnosis of the particle trap. The preset deceleration times can be set to 10 times, 20 times, etc., and can be set according to the route of the vehicle. The ratio is the ratio of the number of times the particle trap is determined to be lost to the number of vehicle deceleration conditions. When the first number and the second number are obtained, the ratio of the first number to the second number can be directly obtained by calculation.

[0132] Step S29: When the ratio reaches a preset ratio, it is determined that the particulate trap is lost.

[0133] It is understood that the preset ratio is a ratio that is set in advance to avoid contingency and is used to accurately determine whether the particulate trap is lost. When the ratio reaches the preset ratio, it can be determined that the particulate trap is lost; when the ratio does not reach the preset ratio, it can be determined that the particulate trap is not lost. For example, if the preset ratio is set to 80%, when the ratio of the first number to the second number reaches 80%, it can be determined that the particulate trap is lost.

[0134] In addition, to achieve the above purpose, refer to Figure 8 The present invention also provides a particle trap diagnostic device, comprising:

[0135] The operating condition detection module 10 is used to detect the operating condition of the vehicle;

[0136] The temperature detection module 20 is used to detect the temperature value downstream of the particulate trap through a temperature sensor downstream of the particulate trap when the vehicle operating condition is a cold start condition;

[0137] a temperature processing module 30, for determining a temperature change rate downstream of the particle trap according to the temperature value;

[0138] The result determination module 40 is used to determine that the particulate trap is lost when the temperature change rate is not within a preset temperature change rate range.

[0139] The particle trap diagnostic device includes: a working condition detection module 10, which is used to detect the vehicle operating condition; a temperature detection module 20, which is used to detect the temperature value downstream of the particle trap through the temperature sensor downstream of the particle trap when the vehicle operating condition is a cold start condition; a temperature processing module 30, which is used to determine the temperature change rate downstream of the particle trap according to the temperature value; and a result identification module 40, which is used to identify that the particle trap is lost when the temperature change rate is not within a preset temperature change rate range. By detecting the operating condition of the vehicle, under the cold start condition, by detecting the temperature value downstream of the particle trap, and judging whether the particle trap is lost according to the temperature change rate of the temperature value downstream of the particle trap, it is realized to diagnose whether the particle trap is lost when the pressure difference sensor cannot work normally under the cold start condition.

[0140] Furthermore, in an embodiment of the particulate filter diagnostic device, the particulate filter diagnostic device is also used to record the engine start time and obtain a first initial temperature through a downstream temperature sensor; when the start time is greater than a preset time threshold, obtain a first current temperature through a downstream temperature sensor; determine a temperature increment based on the first current temperature and the first initial temperature; and when the temperature increment is not within a preset temperature increment range, determine that the particulate filter is lost.

[0141] Furthermore, in an embodiment of the particulate trap diagnostic device, the particulate trap diagnostic device is also used to determine a temperature area based on the first current temperature, the first initial temperature and a preset time threshold; when the temperature area is not within a preset temperature area range, it is determined that the particulate trap is lost.

[0142] Furthermore, in an embodiment of the particulate filter diagnostic device, the particulate filter diagnostic device is also used to detect the current ambient temperature of the vehicle, the current operating state and the duration of the current operating state; when the ambient temperature is lower than a preset temperature threshold, the current operating state is an off state and the duration is greater than a preset time, the vehicle operating condition is determined to be a cold start condition.

[0143] Furthermore, in an embodiment of the particulate filter diagnostic device, the particulate filter diagnostic device is also used to, when the temperature change rate is within a preset temperature change rate range, obtain a second initial temperature through the downstream temperature sensor; when the second initial temperature reaches a preset warm-up temperature, detect the vehicle operating condition; when the vehicle operating condition is a deceleration condition, record the deceleration time of the deceleration condition; when the deceleration time reaches a preset deceleration time threshold, obtain a second current temperature through the downstream temperature sensor; determine the temperature drop downstream of the particulate filter based on the second initial temperature and the second current temperature; and when the temperature drop reaches the preset temperature drop range, determine that the particulate filter is lost.

[0144] Furthermore, in an embodiment of the particulate trap diagnostic device, the particulate trap diagnostic device is also used to, when the temperature drop reaches a preset temperature drop range, record a first number of times the temperature drop reaches the preset temperature drop range and a second number of times the vehicle operating condition is in a deceleration condition, and return to the step of detecting the vehicle operating condition; when the second number reaches a preset deceleration number, obtain a ratio of the first number to the second number; when the ratio reaches a preset ratio, determine that the particulate trap is lost.

[0145] In addition, to achieve the above-mentioned purpose, the present invention further provides a storage medium, on which a particulate trap diagnostic program is stored, and when the particulate trap diagnostic program is executed by a processor, the steps of the particulate trap diagnostic method are implemented.

[0146] In addition, to achieve the above-mentioned purpose, the present invention further provides a computer program product, wherein the computer program product includes a computer program, and when the computer program is executed by a processor, the steps of any one of the above-mentioned particle trap diagnosis methods are implemented.

[0147] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A particle trap diagnostic method, characterized in that: The particle trap diagnostic method comprises: Detect vehicle operating conditions; When the vehicle operating condition is a cold start condition, a temperature value downstream of the particulate trap is detected in real time by a temperature sensor downstream of the particulate trap; determining a rate of change of temperature downstream of the particulate trap based on the temperature value; When the temperature change rate is not within a preset temperature change rate range, it is determined that the particulate trap is lost.

2. The particle trap diagnostic method according to claim 1, characterized in that: After detecting the temperature value downstream of the particulate trap by the temperature sensor downstream of the particulate trap, the method includes: Recording the engine start time and obtaining a first initial temperature through a downstream temperature sensor; When the startup time is greater than a preset time threshold, obtaining a first current temperature through a downstream temperature sensor; determining a temperature increment according to the first current temperature and the first initial temperature; When the temperature increment is not within a preset temperature increment range, it is determined that the particulate trap is lost.

3. The particle trap diagnostic method according to claim 2, characterized in that: When the startup time is greater than the preset time threshold, after obtaining the current temperature through the downstream temperature sensor, the method further includes: Determine a temperature area according to the first current temperature, the first initial temperature and a preset time threshold; When the temperature area is not within the preset temperature area range, it is determined that the particulate trap is lost.

4. The particle trap diagnosis method according to claim 1, characterized in that: The detection of vehicle operating conditions comprises: Detecting the current ambient temperature of the vehicle, the current operating state, and the duration of the current operating state; When the ambient temperature is lower than a preset temperature threshold, the current operating state is an ignition-off state and the duration is greater than a preset duration, the vehicle operating condition is determined to be a cold start condition.

5. The particle trap diagnosis method according to any one of claims 1 to 4, characterized in that: When the vehicle operating condition is a cold start condition, after detecting the temperature value downstream of the particulate trap by a temperature sensor downstream of the particulate trap, the method further includes: When the temperature change rate is within a preset temperature change rate range, obtaining a second initial temperature through the downstream temperature sensor; When the second initial temperature reaches a preset complete warming temperature, detecting a vehicle operating condition; When the vehicle operating condition is a deceleration condition, recording the deceleration time of the deceleration condition; When the deceleration time reaches a preset deceleration time threshold, obtaining a second current temperature through a downstream temperature sensor; determining a temperature drop downstream of the particle trap according to the second initial temperature and the second current temperature; When the temperature drop reaches a preset temperature drop range, it is determined that the particulate trap is lost.

6. The particle trap diagnosis method according to claim 5, characterized in that: After determining the temperature drop amount downstream of the particle trap according to the second initial temperature and the second current temperature, the method further includes: When the temperature drop reaches the preset temperature drop range, recording a first number of times the temperature drop reaches the preset temperature drop range and a second number of times the vehicle operating condition is in a deceleration condition, and returning to the step of detecting the vehicle operating condition; When the second number reaches a preset number of deceleration times, obtaining a ratio of the first number to the second number; When the ratio reaches a preset ratio, it is determined that the particulate trap is lost.

7. A particle trap diagnostic device, characterized in that: The particle trap diagnostic device comprises: A working condition detection module, used to detect the vehicle operating condition; a temperature detection module, used for detecting a temperature value downstream of the particulate trap by a temperature sensor downstream of the particulate trap when the vehicle is in a cold start condition; a temperature processing module, configured to determine a temperature change rate downstream of the particle trap according to the temperature value; The result determination module is used to determine that the particulate trap is lost when the temperature change rate is not within a preset temperature change rate range.

8. A vehicle, characterized in that: The vehicle comprises: a memory, a processor, and a particulate trap diagnostic program stored in the memory and executable on the processor, wherein the particulate trap diagnostic program implements the steps of the particulate trap diagnostic method according to any one of claims 1 to 6 when executed by the processor.

9. A storage medium, characterized in that: The storage medium stores a particulate trap diagnostic program, which, when executed by the processor, implements the steps of the particulate trap diagnostic method according to any one of claims 1 to 6.

10. A computer program product, characterized in that The computer program product comprises a computer program, and when the computer program is executed by a processor, the steps of the particle trap diagnosis method according to any one of claims 1 to 6 are implemented.

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