Diagnostic method, device, equipment and medium for exhaust gas recirculation cooler carbon deposition problem
By acquiring the engine's target operating parameters and exhaust gas temperature, and using a standard gauge to determine the carbon buildup, this technology solves the problem of difficulty in timely diagnosing exhaust gas recirculation cooler blockage in existing technologies. It enables timely treatment of initial carbon buildup, prevents blockage, and ensures vehicle safety.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- DONGFENG MOTOR GRP
- Filing Date
- 2026-03-30
- Publication Date
- 2026-06-16
AI Technical Summary
Existing technology makes it difficult to detect blockages in the exhaust gas recirculation cooler in the early stages of carbon buildup, leading to the need for replacement and repair when the blockage becomes severe.
By obtaining the actual values of the engine's target operating parameters and the actual value of the exhaust temperature, the carbon buildup situation is determined using the exhaust temperature standard table, the deviation rate is calculated to judge the degree of carbon buildup, and remedial measures are taken in the early stages of carbon buildup.
It enables timely detection of exhaust gas recirculation cooler blockage in the early stages of carbon buildup, preventing complete blockage and ensuring vehicle safety.
Smart Images
Figure CN122215972A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of exhaust gas recirculation cooler technology, and in particular to a method, apparatus, equipment and medium for diagnosing carbon buildup problems in exhaust gas recirculation coolers. Background Technology
[0002] Low-pressure exhaust gas recirculation (EGR) is one of the core features of existing hybrid-specific engines. To achieve better fuel economy, the current mainstream EGR system uses a pre-catalytic converter intake scheme (exhaust gas without a particulate filter, containing a certain amount of carbon and hydrogen). However, this pre-catalytic converter intake scheme often faces the problem of dirty exhaust gas, especially in scenarios with incomplete combustion, resulting in more carbon soot and carbon buildup, leading to blockage of the EGR cooler. Once the EGR cooler is blocked, heat exchange efficiency decreases, causing the gas temperature entering the intake manifold to be too high, which in turn leads to poor combustion. Current solutions use a gas temperature sensor at the EGR cooler outlet. When the sensor detects a temperature exceeding a certain threshold (e.g., 170°C), it indicates an abnormal temperature requiring maintenance. However, EGR cooler blockage is often a relatively long process, mainly because prolonged low loads or incomplete combustion lead to an accumulation of unburned carbon particles, gradually causing blockage. However, carbon buildup is a reversible process. When combustion is relatively complete and the flow rate is relatively high, the initially accumulated carbon deposits can be slowly carried away and burned off. If only the outlet temperature is used for alarm settings, by the time the alarm is triggered, the blockage problem is often already quite serious, requiring replacement and repair. Therefore, a new diagnostic method for carbon buildup problems in exhaust gas recirculation coolers needs to be designed to promptly determine the blockage status of the exhaust gas recirculation cooler. Summary of the Invention
[0003] This application provides a diagnostic method, apparatus, equipment, and medium for carbon buildup problems in exhaust gas recirculation coolers, which solves the shortcomings of existing technologies that make it difficult to promptly identify blockage problems in exhaust gas recirculation coolers in the early stages of carbon buildup, and enables timely identification of blockage problems in exhaust gas recirculation coolers in the early stages of carbon buildup.
[0004] In a first aspect, this application provides a method for diagnosing carbon buildup problems in exhaust gas recirculation coolers, including: After the vehicle is powered on, if the vehicle's engine starts and the engine's exhaust gas recirculation valve opens, the actual values of the engine's target operating parameters and the actual value of the exhaust gas recirculation cooler's outlet temperature when the engine is running at the actual values of the target operating parameters are obtained; the target operating parameters affect the outlet temperature of the exhaust gas recirculation cooler. Based on the actual value of the outlet air temperature and the target outlet air temperature standard value, the carbon buildup of the exhaust gas recirculation cooler is determined; the target outlet air temperature standard value is the outlet air temperature standard value of the exhaust gas recirculation cooler when the engine is running under the actual value of the target operating parameters. The target outlet air temperature standard value is determined based on an outlet air temperature standard table, which includes the outlet air temperature standard values of the exhaust gas recirculation cooler when the engine is running under different values of the target operating parameters.
[0005] Optionally, the target operating parameters are selected from various operating parameters of the engine using the controlled variable method. The target operating parameters include ambient temperature, engine coolant temperature, engine intake airflow, engine exhaust temperature, and engine exhaust gas recirculation rate.
[0006] Optionally, the outlet temperature standard table is determined in the following manner: Multiple preset values of the ambient temperature, multiple preset values of the water temperature, multiple preset values of the intake air volume, multiple preset values of the exhaust temperature, and multiple preset values of the exhaust gas recirculation rate are obtained. Obtain standard values of outlet temperature under different preset combinations of ambient temperature, water temperature, air inlet flow rate, exhaust temperature and exhaust gas recirculation rate under standard test conditions, and form an initial outlet temperature table. The initial outlet temperature table is interpolated using an interpolation method to obtain the standard outlet temperature table.
[0007] Optionally, determining the carbon buildup in the exhaust gas recirculation cooler based on the actual exhaust gas temperature and the target exhaust gas temperature standard value includes: Calculate the first integral value of the actual outlet temperature over time, and the second integral value of the target outlet temperature standard value over time; Calculate the absolute value of the deviation rate between the first integral value and the second integral value; Based on the magnitude of the absolute value, it is determined whether the exhaust gas recirculation cooler has a carbon buildup problem and the degree of carbon buildup.
[0008] Optionally, determining whether the exhaust gas recirculation cooler has a carbon buildup problem and the degree of carbon buildup based on the magnitude of the absolute value includes: If the absolute value is less than or equal to the first threshold, it is determined that the exhaust gas recirculation cooler does not have a carbon buildup problem; If the absolute value is greater than the first threshold and less than the second threshold, it is determined that the exhaust gas recirculation cooler has a carbon buildup problem, and the degree of carbon buildup is the first degree. If the absolute value is greater than or equal to the second threshold, it is determined that the exhaust gas recirculation cooler has a carbon buildup problem, and the degree of carbon buildup is the second degree; the second degree is more severe than the first degree.
[0009] Optionally, if the degree of carbon deposition is the first degree, the method further includes: Increase the vehicle's state of charge balance point to control engine start-up; After the engine starts, it charges the vehicle's battery pack for a first duration under target operating conditions, and while charging the battery pack, it increases the engine's exhaust gas recirculation rate to a target value. If the charging time for the battery pack is less than the first time, the vehicle is powered off. When the vehicle is powered on again, the engine is controlled to continue charging the battery pack under the target operating condition until the cumulative charging time for the battery pack reaches the first time. While continuing to charge the battery pack, the exhaust gas recirculation rate is increased to the target value.
[0010] Optionally, if the degree of carbon deposition is the second degree, the method further includes: Increase the vehicle's state of charge balance point to control engine start-up; After the engine starts, it charges the battery pack for a second duration under the target operating condition, and while charging the battery pack, it increases the exhaust gas recirculation rate to the target value; the second duration is longer than the first duration. If the charging time for the battery pack is less than the second duration, the vehicle is powered off. When the vehicle is powered on again, the engine is controlled to continue charging the battery pack under the target operating condition until the cumulative charging time for the battery pack reaches the second duration. While continuing to charge the battery pack, the exhaust gas recirculation rate is increased to the target value.
[0011] Secondly, this application also provides a diagnostic device for carbon buildup problems in exhaust gas recirculation coolers, comprising: The data acquisition module is used to acquire, after the vehicle is powered on, if the vehicle's engine starts and the engine's exhaust gas recirculation valve is open, the actual value of the engine's target operating parameters, and the actual value of the exhaust gas recirculation cooler's outlet temperature when the engine is running under the actual value of the target operating parameters; the target operating parameters affect the exhaust gas recirculation cooler's outlet temperature. The determination module is used to determine the carbon buildup of the exhaust gas recirculation cooler based on the actual value of the exhaust gas temperature and the target standard value of the exhaust gas temperature. The target standard value of the exhaust gas temperature is the standard value of the exhaust gas temperature of the exhaust gas recirculation cooler when the engine is running at the actual value of the target operating parameters. The target standard value of the exhaust gas temperature is determined based on an exhaust gas temperature standard table, which includes the standard values of the exhaust gas temperature of the exhaust gas recirculation cooler when the engine is running at different values of the target operating parameters.
[0012] Thirdly, this application also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the method described in the first aspect.
[0013] Fourthly, this application also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method described in the first aspect.
[0014] Fifthly, this application also provides a computer program product, including a computer program that, when executed by a processor, implements the method described in the first aspect.
[0015] The diagnostic method, apparatus, equipment, and medium for carbon buildup in exhaust gas recirculation (EGR) coolers provided in this application determine the target outlet temperature standard value of the EGR cooler when the engine is running at the actual target operating parameters by using an outlet temperature standard table composed of standard outlet temperature values of the EGR cooler when the engine is running at different target operating parameters. Then, the target outlet temperature standard value is compared with the actual outlet temperature of the EGR cooler when the engine is running at the actual target operating parameters to determine the carbon buildup situation in the EGR cooler. This allows for timely detection of blockage in the EGR cooler at the initial stage of carbon buildup, facilitating timely remedial measures to remove initial carbon buildup and prevent complete blockage of the EGR cooler, thus ensuring vehicle safety. Attached Figure Description
[0016] To more clearly illustrate the technical solutions in this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0017] Figure 1 This is a flowchart illustrating the diagnostic method for carbon buildup in exhaust gas recirculation coolers provided in this application embodiment; Figure 2 This is a schematic diagram of the structure of the diagnostic device for carbon buildup in the exhaust gas recirculation cooler provided in the embodiments of this application; Figure 3 This is a schematic diagram of the structure of the electronic device provided in the embodiments of this application. Detailed Implementation
[0018] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0019] This application provides a diagnostic method for carbon buildup problems in exhaust gas recirculation coolers. The executing entity can be an electronic device, such as a controller in a vehicle. The following description uses a controller as the executing entity of the method. Figure 1 This is a schematic flowchart illustrating the diagnostic method for carbon buildup in exhaust gas recirculation coolers provided in this application embodiment. (Refer to...) Figure 1 The method may include: Step 110: After the vehicle is powered on, if the vehicle's engine starts and the engine's exhaust gas recirculation valve opens, obtain the actual value of the engine's target operating parameters, and the actual value of the exhaust gas recirculation cooler's outlet temperature when the engine is running under the actual value of the target operating parameters; the target operating parameters affect the exhaust gas recirculation cooler's outlet temperature. Step 120: Determine the carbon buildup on the exhaust gas recirculation cooler based on the actual exhaust gas temperature and the target exhaust gas temperature standard value. The target exhaust gas temperature standard value is the exhaust gas recirculation cooler's exhaust gas temperature standard value when the engine is running at the actual value of the target operating parameters. The target exhaust gas temperature standard value is determined based on the exhaust gas temperature standard table, which includes the exhaust gas recirculation cooler's exhaust gas temperature standard values when the engine is running at different values of the target operating parameters.
[0020] In step 110, the controller can acquire the actual values of the engine's target operating parameters when the engine is started and the exhaust gas recirculation valve is open, as well as the actual value of the exhaust gas recirculation cooler's outlet temperature when the engine is running at the actual values of the target operating parameters. The actual outlet temperature of the exhaust gas recirculation cooler differs depending on the target operating parameter values. In other words, the target operating parameters affect the outlet temperature of the exhaust gas recirculation cooler.
[0021] In step 120, the controller can determine the carbon buildup on the exhaust gas recirculation cooler by comparing the deviation between the actual exhaust gas temperature and the target exhaust gas temperature standard value. Specifically, the standard exhaust gas temperature of the exhaust gas recirculation cooler can be obtained first through experiments when the engine is running at different target operating parameters, resulting in an exhaust gas temperature standard table. Then, when the controller obtains the actual target operating parameters of the engine and the actual exhaust gas temperature of the exhaust gas recirculation cooler, it simultaneously obtains the target exhaust gas temperature standard value of the exhaust gas recirculation cooler from the corresponding exhaust gas temperature standard table, and compares the two to determine the carbon buildup on the exhaust gas recirculation cooler.
[0022] The diagnostic method for carbon buildup in exhaust gas recirculation (EGR) coolers provided in this application determines the target outlet temperature standard value of the EGR cooler when the engine is running at the actual target operating parameters by using an outlet temperature standard table composed of standard outlet temperature values of the EGR cooler when the engine is running at different target operating parameters. Then, the target outlet temperature standard value is compared with the actual outlet temperature value of the EGR cooler when the engine is running at the actual target operating parameters to determine the carbon buildup situation of the EGR cooler. This method can promptly identify blockage problems in the EGR cooler in the early stages of carbon buildup, facilitating timely remedial measures to remove initial carbon buildup and prevent the EGR cooler from becoming completely blocked, thus ensuring vehicle safety.
[0023] In some embodiments, the target operating parameters are selected from various operating parameters of the engine by means of controlled variables. The target operating parameters include ambient temperature, engine coolant temperature, engine intake airflow, engine exhaust temperature, and engine exhaust gas recirculation rate.
[0024] The controller can use the controlled variable method to manage various engine operating parameters, treating each parameter as an independent variable and the actual exhaust gas recirculation cooler outlet temperature as a dependent variable. From these parameters, a target operating parameter is selected that primarily affects the actual exhaust gas recirculation cooler outlet temperature. This target operating parameter also reflects the engine's operating state.
[0025] Ambient temperature, engine coolant temperature, engine intake airflow, engine exhaust temperature, and engine exhaust gas recirculation (EGR) rate are the main factors affecting the actual outlet temperature of the EGR cooler. Specifically, ambient temperature directly impacts the overall gas temperature level of the intake system; engine coolant temperature directly affects the heat exchange efficiency of the EGR cooler, with lower coolant temperatures effectively reducing the outlet temperature; engine intake airflow and EGR rate determine the amount of gas entering the EGR cooler, directly affecting the outlet temperature assuming a consistent heat exchange boundary; and engine exhaust temperature directly affects the initial temperature entering the EGR cooler.
[0026] The diagnostic method for carbon buildup in exhaust gas recirculation coolers provided in this application uses a controlled variable method to screen out target operating parameters that affect the actual outlet temperature of the exhaust gas recirculation cooler, including ambient temperature, engine coolant temperature, engine intake airflow, engine exhaust temperature, and engine exhaust gas recirculation rate. By comparing the deviation between the actual outlet temperature and the target outlet temperature standard value when the engine is running at the same target operating parameter values, the blockage problem of the exhaust gas recirculation cooler can be effectively determined.
[0027] In some embodiments, the outlet temperature standard table is determined as follows: multiple preset values of ambient temperature, multiple preset values of water temperature, multiple preset values of intake airflow, multiple preset values of exhaust temperature, and multiple preset values of exhaust gas recirculation rate are obtained; standard values of outlet temperature are obtained under different combinations of preset values of ambient temperature, water temperature, intake airflow, exhaust temperature, and exhaust gas recirculation rate under standard test conditions, and an initial outlet temperature table is formed; the initial outlet temperature table is interpolated using an interpolation method to obtain the outlet temperature standard table.
[0028] The initial outlet air temperature is shown in Table 1 below:
[0029] Table 1 Initial Outlet Temperature This application considers ambient temperatures as low as 5°C, where EGR is not activated, and the typical maximum ambient temperature operating range is 45°C. The air volume range is illustrated as 400 to 1000 (the range varies depending on the engine characteristics). The maximum exhaust temperature is 850°C, and EGR is generally not activated below 600°C. The load is set at a maximum of 100% and a minimum of no load (3%). Multiple preset values are defined for ambient water temperature: 5°C, 25°C, and 45°C; water temperature: 60°C, 90°C, and 110°C; intake air volume: 400 kg / h, 700 kg / h, and 1000 kg / h; exhaust temperature: 600°C, 700°C, and 850°C; and exhaust gas recirculation rate: 30%, 15%, and 3%. The controller can acquire these preset values for ambient water temperature, water temperature, intake air volume, exhaust temperature, and exhaust gas recirculation rate. The controller can then acquire the standard value of the outlet temperature under different preset combinations of ambient water temperature, water temperature, air intake flow rate, exhaust temperature and exhaust gas recirculation rate in the standard bench test, and form an initial outlet temperature table.
[0030] The specific test process is as follows: In a standard vehicle environmental chamber, under different ambient temperatures (5~45℃, combined with the ambient temperature for EGR use), the engine coolant temperature is controlled to a stable level (e.g., 60~110℃, combined with the coolant temperature requirements for EGR use), the engine intake air volume is controlled to a stable level (e.g., 400~1000kg / h, combined with the air volume requirements for EGR use), and the engine exhaust temperature is controlled to a stable level (e.g., 600~850℃). When adjusting different EGR levels (e.g., 3%~30%, adjusted according to the actual EGR usage range), the outlet air temperature of the EGR cooler under different operating conditions is recorded, forming Table 1. Table 1 shows the standard values of exhaust gas temperature obtained by combining multiple preset values of ambient water temperature (5℃, 25℃, 45℃), water temperature (60℃, 90℃, 110℃), intake airflow (400kg / h, 700kg / h, 1000kg / h), exhaust temperature (600℃, 700℃, 850℃), and exhaust gas recirculation rate (30%, 15%, 3%).
[0031] The diagnostic method for carbon buildup in exhaust gas recirculation coolers provided in this application involves testing standard values of outlet temperature under different preset combinations of ambient temperature, water temperature, inlet flow rate, exhaust temperature, and exhaust gas recirculation rate in a standard test environment to form an initial outlet temperature table. Then, through interpolation processing, an outlet temperature standard table is obtained, which can obtain accurate outlet temperature standard values. This facilitates comparison with the actual outlet temperature values to determine the carbon buildup situation of the exhaust gas recirculation cooler.
[0032] In some embodiments, determining the carbon buildup status of the exhaust gas recirculation cooler based on the actual exhaust gas temperature and the target exhaust gas temperature standard value includes: calculating a first integral value of the actual exhaust gas temperature over time and a second integral value of the target exhaust gas temperature standard value over time; calculating the absolute value of the deviation rate between the first integral value and the second integral value; and determining whether the exhaust gas recirculation cooler has a carbon buildup problem and the degree of carbon buildup based on the magnitude of the absolute value.
[0033] The controller can continuously acquire the actual values of the engine's target operating parameters, i.e., ambient temperature T, after the vehicle is powered on, the engine is started, and the exhaust gas recirculation valve is open. 环境 Engine coolant temperature T 水温 Engine intake airflow Q, engine exhaust temperature T 排温 The engine's EGR rate S, and the actual real-time exhaust gas recirculation cooler outlet temperature T corresponding to the actual values of the target operating parameters. 气温 It also calculates the first integral value T of the actual air temperature over time in real time. 气温sum T 气温sum =∫0 t T 气温t（T环境、T水温、Q、T排温、S） d t , among which, T 气温t（T环境、T水温、Q、T排温、S） This refers to the real-time exhaust gas temperature corresponding to the actual value of the engine's current target operating parameters, that is, the actual exhaust gas recirculation cooler's exhaust gas temperature when the engine is running under the target operating parameters. Specifically, the target operating parameters of the engine, obtained when the engine is started and the exhaust gas recirculation valve is open, are numerically selected by satisfying 5 < T. 环境 <45℃, 60<T 水温 <110℃, 400<Q<1000kg / h, 600<T 排温 Actual outlet temperature T <850℃ and 3% < S < 30% 气温 .
[0034] While acquiring the actual values of the engine's target operating parameters, the controller can also obtain the target outlet temperature standard value of the exhaust gas recirculation cooler when the engine is running under the actual target operating parameters via the outlet temperature standard table, and calculate the second integral value T of the target outlet temperature standard value with respect to time in real time. 气温sum标准 T 气温sum标准 =∫0 t T 气温t标准（T环境、T水温、Q、T排温、S） d t , among which, T 气温t标准（T环境、T水温、Q、T排温、S）This refers to the target outlet temperature standard value corresponding to the actual value of the engine's current target operating parameters, that is, the target outlet temperature standard value of the engine's exhaust gas recirculation cooler when the engine is running under the actual value of the target operating parameters. Then, the absolute value δ of the deviation rate between the first integral value and the second integral value is calculated in real time, δ = |T 气温sum -T 气温sum标准 | / T 气温sum标准 And based on the magnitude of δ, determine whether the exhaust gas recirculation cooler has carbon buildup and the degree of carbon buildup.
[0035] The diagnostic method for carbon buildup in the exhaust gas recirculation cooler provided in this application, after the vehicle is powered on and the engine is started with the exhaust gas recirculation valve open, diagnoses whether there is a carbon buildup problem in the exhaust gas recirculation cooler by measuring the deviation rate between the actual value of the exhaust gas recirculation cooler's outlet temperature and the target outlet temperature standard value when the engine is running at the actual value of the target operating parameters. This method can promptly identify the blockage problem of the exhaust gas recirculation cooler in the early stages of carbon buildup, facilitating timely remedial measures to remove the initial carbon buildup and prevent the exhaust gas recirculation cooler from becoming completely blocked, thus ensuring vehicle safety.
[0036] In some embodiments, determining whether the exhaust gas recirculation cooler has a carbon buildup problem and the degree of carbon buildup based on the magnitude of the absolute value includes: if the absolute value is less than or equal to a first threshold, determining that the exhaust gas recirculation cooler does not have a carbon buildup problem; if the absolute value is greater than the first threshold and less than a second threshold, determining that the exhaust gas recirculation cooler has a carbon buildup problem, and the degree of carbon buildup is the first degree; if the absolute value is greater than or equal to the second threshold, determining that the exhaust gas recirculation cooler has a carbon buildup problem, and the degree of carbon buildup is the second degree; the second degree is more severe than the first degree.
[0037] For example, the first threshold is 5%, and the second threshold is 10%. If the exhaust gas recirculation cooler does not have a carbon buildup problem, the actual outlet temperature is usually not much different from the target outlet temperature standard, i.e., δ≤5%. If the exhaust gas recirculation cooler has a carbon buildup problem, the actual outlet temperature is usually significantly higher than the target outlet temperature standard, in which case δ>5%. The higher the actual outlet temperature is compared to the target outlet temperature standard, the more severe the carbon buildup problem. When 5%<δ<10%, the exhaust gas recirculation cooler is judged to have a carbon buildup problem, and the degree of carbon buildup is the first level, i.e., slight carbon buildup. When δ≥10%, the exhaust gas recirculation cooler is judged to have a carbon buildup problem, and the degree of carbon buildup is the second level, i.e., severe carbon buildup.
[0038] The diagnostic method for carbon buildup in the exhaust gas recirculation cooler provided in this application, after the vehicle is powered on and the engine is started with the exhaust gas recirculation valve open, diagnoses the presence and degree of carbon buildup in the exhaust gas recirculation cooler by measuring the deviation rate between the actual exhaust gas temperature and the target standard exhaust gas temperature when the engine is running at the actual value of the target operating parameters. This allows for timely implementation of different treatment measures based on the degree of carbon buildup, ensuring vehicle safety.
[0039] In some embodiments, if the carbon buildup level is at the first level, the method for diagnosing carbon buildup in the exhaust gas recirculation cooler further includes: increasing the vehicle's state of charge balance point to control engine startup; controlling the engine to charge the vehicle's battery pack for a first duration under target operating conditions after startup, and increasing the engine's exhaust gas recirculation rate to a target value while charging the battery pack; if the charging time for the battery pack is less than the first duration, the vehicle is powered off, and when the vehicle is powered on again, controlling the engine to continue charging the battery pack under target operating conditions until the cumulative charging time for the battery pack reaches the first duration, and increasing the exhaust gas recirculation rate to a target value while continuing to charge the battery pack.
[0040] The controller can increase the vehicle's State of Charge (SOC) balance point, for example, to 80%. When SOC < 80%, the engine is forcibly started, exiting the original energy management strategy. The controller can then control the engine to operate at the optimal economic point (i.e., the target operating condition), while adjusting the EGR rate to the maximum (i.e., the target value). This ensures sufficient exhaust gas flow into the EGR cooler while minimizing particulate matter, using clean exhaust gas to remove initial carbon deposits. For example: engine speed 2000 rpm, engine torque 100 Nm, EGR rate adjusted to the highest (e.g., 30%), maintaining this operating condition for a first duration (e.g., 3 minutes). If the vehicle loses power during this forced engine start-up and operation, the operating time under this target condition is recorded. After the vehicle is powered on again and driven, the engine is forcibly started again until it runs for the full 3 minutes.
[0041] After the above carbon removal strategy is performed, the EGR cooler carbon buildup monitoring process is repeated during normal engine operation. The system then determines whether to continue the carbon removal strategy based on the real-time monitoring and diagnostic results.
[0042] The diagnostic method for carbon buildup in the exhaust gas recirculation cooler provided in this application, after the vehicle is powered on and the engine is started with the exhaust gas recirculation valve open, diagnoses the presence and degree of carbon buildup in the exhaust gas recirculation cooler by measuring the deviation rate between the actual exhaust gas temperature and the target standard exhaust gas temperature when the engine is running at the actual value of the target operating parameters. In the early stages of blockage, the method optimizes strategies, such as running under conditions of complete combustion for a period of time, to remove the carbon buildup and prevent the EGR cooler from becoming completely blocked.
[0043] In some embodiments, if the carbon buildup level is the second level, the method for diagnosing carbon buildup in the exhaust gas recirculation cooler further includes: increasing the vehicle's state of charge balance point to control engine startup; controlling the engine to charge the battery pack for a second duration under target operating conditions after startup, and increasing the exhaust gas recirculation rate to a target value while charging the battery pack; the second duration being greater than the first duration; if the battery pack charging time is less than the second duration, the vehicle is powered off, and when the vehicle is powered on again, controlling the engine to continue charging the battery pack under target operating conditions until the cumulative charging time of the battery pack reaches the second duration, and increasing the exhaust gas recirculation rate to a target value while continuing to charge the battery pack.
[0044] The controller can increase the vehicle's State of Charge (SOC) balance point, for example, to 80%. When SOC < 80%, the engine is forcibly started, exiting the original energy management strategy. The controller can then control the engine to operate at the optimal economic point (i.e., the target operating condition), while adjusting the EGR rate to the maximum (i.e., the target value). This ensures sufficient exhaust gas flow into the EGR cooler while minimizing particulate matter, using clean exhaust gas to remove initial carbon deposits. For example: engine speed 2000 rpm, engine torque 100 Nm, EGR rate adjusted to the highest (e.g., 30%), maintaining this operating condition for a second duration (e.g., 10 minutes). If the vehicle loses power during this forced engine start-up and operation, the operating time under this target condition is recorded. After the vehicle is powered on again and driven, the engine is forcibly started again until the full 10 minutes are completed.
[0045] After the above carbon removal strategy is performed, the EGR cooler carbon buildup monitoring process is repeated during normal engine operation. The system then determines whether to continue the carbon removal strategy based on the real-time monitoring and diagnostic results.
[0046] The diagnostic method for carbon buildup in the exhaust gas recirculation cooler provided in this application, after the vehicle is powered on and the engine is started with the exhaust gas recirculation valve open, diagnoses the presence and degree of carbon buildup in the exhaust gas recirculation cooler by measuring the deviation rate between the actual exhaust gas temperature and the target standard exhaust gas temperature when the engine is running at the actual value of the target operating parameters. In the early stages of blockage, the method optimizes strategies, such as running under conditions of complete combustion for a period of time, to remove the carbon buildup and prevent the EGR cooler from becoming completely blocked.
[0047] The diagnostic apparatus for carbon buildup in exhaust gas recirculation coolers provided in this application is described below. The diagnostic apparatus for carbon buildup in exhaust gas recirculation coolers described below can be referred to in correspondence with the diagnostic method for carbon buildup in exhaust gas recirculation coolers described above.
[0048] Figure 2 This is a schematic diagram of the diagnostic device for carbon buildup problems in the exhaust gas recirculation cooler provided in this embodiment of the application. (Refer to...) Figure 2 The diagnostic device for carbon buildup problems in exhaust gas recirculation coolers provided in this application embodiment may include: The data acquisition module 210 is used to acquire, after the vehicle is powered on, if the vehicle's engine starts and the engine's exhaust gas recirculation valve is open, the actual value of the target operating parameters of the engine, and the actual value of the exhaust gas recirculation cooler's outlet temperature when the engine is running under the actual value of the target operating parameters; the target operating parameters affect the outlet temperature of the exhaust gas recirculation cooler. The determination module 220 is used to determine the carbon buildup of the exhaust gas recirculation cooler based on the actual value of the exhaust gas temperature and the target exhaust gas temperature standard value. The target exhaust gas temperature standard value is the exhaust gas temperature standard value of the exhaust gas recirculation cooler when the engine is running at the actual value of the target operating parameters. The target exhaust gas temperature standard value is determined based on an exhaust gas temperature standard table, which includes the exhaust gas temperature standard values of the exhaust gas recirculation cooler when the engine is running at different values of the target operating parameters.
[0049] The diagnostic device for carbon buildup in the exhaust gas recirculation cooler provided in this application determines the target exhaust gas recirculation cooler's standard outlet temperature when the engine is running at different target operating parameters by using an outlet temperature standard table composed of standard outlet temperature values of the exhaust gas recirculation cooler when the engine is running at different target operating parameters. Then, it compares the target outlet temperature standard value with the actual outlet temperature of the exhaust gas recirculation cooler when the engine is running at the actual target operating parameters to determine the carbon buildup situation of the exhaust gas recirculation cooler. This device can promptly identify the blockage problem of the exhaust gas recirculation cooler in the early stages of carbon buildup, facilitating timely remedial measures to remove the initial carbon buildup and prevent the exhaust gas recirculation cooler from becoming completely blocked, thus ensuring vehicle safety.
[0050] In some embodiments, the target operating parameters are selected from various operating parameters of the engine using a controlled variable method. The target operating parameters include ambient temperature, engine coolant temperature, engine intake airflow, engine exhaust temperature, and engine exhaust gas recirculation rate.
[0051] In some embodiments, the outlet temperature standard table is determined in the following manner: Multiple preset values of the ambient temperature, multiple preset values of the water temperature, multiple preset values of the intake air volume, multiple preset values of the exhaust temperature, and multiple preset values of the exhaust gas recirculation rate are obtained. Obtain standard values of outlet temperature under different preset combinations of ambient temperature, water temperature, air inlet flow rate, exhaust temperature and exhaust gas recirculation rate under standard test conditions, and form an initial outlet temperature table. The initial outlet temperature table is interpolated using an interpolation method to obtain the standard outlet temperature table.
[0052] In some embodiments, the determining module is used to: Calculate the first integral value of the actual outlet temperature over time, and the second integral value of the target outlet temperature standard value over time; Calculate the absolute value of the deviation rate between the first integral value and the second integral value; Based on the magnitude of the absolute value, it is determined whether the exhaust gas recirculation cooler has a carbon buildup problem and the degree of carbon buildup.
[0053] In some embodiments, the determining module is used to: If the absolute value is less than or equal to the first threshold, it is determined that the exhaust gas recirculation cooler does not have a carbon buildup problem; If the absolute value is greater than the first threshold and less than the second threshold, it is determined that the exhaust gas recirculation cooler has a carbon buildup problem, and the degree of carbon buildup is the first degree. If the absolute value is greater than or equal to the second threshold, it is determined that the exhaust gas recirculation cooler has a carbon buildup problem, and the degree of carbon buildup is the second degree; the second degree is more severe than the first degree.
[0054] In some embodiments, if the degree of carbon deposition is the first degree, the determining module is further configured to: Increase the vehicle's state of charge balance point to control engine start-up; After the engine starts, it charges the vehicle's battery pack for a first duration under target operating conditions, and while charging the battery pack, it increases the engine's exhaust gas recirculation rate to a target value. If the charging time for the battery pack is less than the first time, the vehicle is powered off. When the vehicle is powered on again, the engine is controlled to continue charging the battery pack under the target operating condition until the cumulative charging time for the battery pack reaches the first time. While continuing to charge the battery pack, the exhaust gas recirculation rate is increased to the target value.
[0055] In some embodiments, if the degree of carbon deposition is the second degree, the determining module is further configured to: Increase the vehicle's state of charge balance point to control engine start-up; After the engine starts, it charges the battery pack for a second duration under the target operating condition, and while charging the battery pack, it increases the exhaust gas recirculation rate to the target value; the second duration is longer than the first duration. If the charging time for the battery pack is less than the second duration, the vehicle is powered off. When the vehicle is powered on again, the engine is controlled to continue charging the battery pack under the target operating condition until the cumulative charging time for the battery pack reaches the second duration. While continuing to charge the battery pack, the exhaust gas recirculation rate is increased to the target value.
[0056] Specifically, the diagnostic device for carbon buildup in the exhaust gas recirculation cooler provided in this application embodiment can implement all the method steps of the method embodiment with the controller as the execution subject, and can achieve the same technical effect. Here, the parts that are the same as those in the method embodiment and the beneficial effects will not be described in detail.
[0057] Figure 3 This is a schematic diagram of the structure of the electronic device provided in an embodiment of this application. For example... Figure 3As shown, the electronic device may include: a processor 310, a communications interface 320, a memory 330, and a communication bus 340, wherein the processor 310, the communications interface 320, and the memory 330 communicate with each other via the communication bus 340. The processor 310 can call logical instructions in the memory 330 to execute diagnostic methods for carbon buildup problems in the exhaust gas recirculation cooler, such as: After the vehicle is powered on, if the vehicle's engine starts and the engine's exhaust gas recirculation valve opens, the actual values of the engine's target operating parameters and the actual value of the exhaust gas recirculation cooler's outlet temperature when the engine is running at the actual values of the target operating parameters are obtained; the target operating parameters affect the outlet temperature of the exhaust gas recirculation cooler. Based on the actual value of the outlet air temperature and the target outlet air temperature standard value, the carbon buildup of the exhaust gas recirculation cooler is determined; the target outlet air temperature standard value is the outlet air temperature standard value of the exhaust gas recirculation cooler when the engine is running under the actual value of the target operating parameters. The target outlet air temperature standard value is determined based on an outlet air temperature standard table, which includes the outlet air temperature standard values of the exhaust gas recirculation cooler when the engine is running under different values of the target operating parameters.
[0058] Furthermore, the logical instructions in the aforementioned memory 330 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.
[0059] On the other hand, this application also provides a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the diagnostic method for carbon deposit problems in exhaust gas recirculation coolers provided by the above methods, including, for example: After the vehicle is powered on, if the vehicle's engine starts and the engine's exhaust gas recirculation valve opens, the actual values of the engine's target operating parameters and the actual value of the exhaust gas recirculation cooler's outlet temperature when the engine is running at the actual values of the target operating parameters are obtained; the target operating parameters affect the outlet temperature of the exhaust gas recirculation cooler. Based on the actual value of the outlet air temperature and the target outlet air temperature standard value, the carbon buildup of the exhaust gas recirculation cooler is determined; the target outlet air temperature standard value is the outlet air temperature standard value of the exhaust gas recirculation cooler when the engine is running under the actual value of the target operating parameters. The target outlet air temperature standard value is determined based on an outlet air temperature standard table, which includes the outlet air temperature standard values of the exhaust gas recirculation cooler when the engine is running under different values of the target operating parameters.
[0060] Furthermore, this application also provides a computer program product, which includes a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer is able to perform the steps of the diagnostic methods for carbon buildup problems in exhaust gas recirculation coolers provided by the above-described methods, for example including: After the vehicle is powered on, if the vehicle's engine starts and the engine's exhaust gas recirculation valve opens, the actual values of the engine's target operating parameters and the actual value of the exhaust gas recirculation cooler's outlet temperature when the engine is running at the actual values of the target operating parameters are obtained; the target operating parameters affect the outlet temperature of the exhaust gas recirculation cooler. Based on the actual value of the outlet air temperature and the target outlet air temperature standard value, the carbon buildup of the exhaust gas recirculation cooler is determined; the target outlet air temperature standard value is the outlet air temperature standard value of the exhaust gas recirculation cooler when the engine is running under the actual value of the target operating parameters. The target outlet air temperature standard value is determined based on an outlet air temperature standard table, which includes the outlet air temperature standard values of the exhaust gas recirculation cooler when the engine is running under different values of the target operating parameters.
[0061] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.
[0062] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.
[0063] It should also be noted that in the embodiments of this application, the terms "first," "second," etc., are used to distinguish similar objects, and not to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first" and "second" are generally of the same class, and the number of objects is not limited. For example, the first object can be one or more.
[0064] In this application's embodiments, the term "and / or" describes the association relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.
[0065] In this application's embodiments, "determine B based on A" means that factor A must be considered when determining B. It is not limited to "B can be determined based solely on A," but should also include: "determine B based on A and C," "determine B based on A, C, and E," "determine C based on A, and further determine B based on C," etc. Additionally, it can include using A as a condition for determining B, for example, "when A meets the first condition, determine B using the first method"; another example, "when A meets the second condition, determine B," etc.; another example, "when A meets the third condition, determine B based on the first parameter," etc. Of course, it can also be a condition where A is a factor in determining B, for example, "when A meets the first condition, determine C using the first method, and further determine B based on C," etc.
[0066] In the embodiments of this application, the term "multiple" refers to two or more, and other quantifiers are similar.
[0067] In this application, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this application, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.
[0068] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.
Claims
1. A method for diagnosing carbon buildup problems in exhaust gas recirculation coolers, characterized in that, include: After the vehicle is powered on, if the vehicle's engine starts and the engine's exhaust gas recirculation valve opens, the actual values of the engine's target operating parameters and the actual value of the exhaust gas recirculation cooler's outlet temperature when the engine is running at the actual values of the target operating parameters are obtained; the target operating parameters affect the outlet temperature of the exhaust gas recirculation cooler. Based on the actual value of the outlet air temperature and the target outlet air temperature standard value, the carbon buildup of the exhaust gas recirculation cooler is determined; the target outlet air temperature standard value is the outlet air temperature standard value of the exhaust gas recirculation cooler when the engine is running under the actual value of the target operating parameters. The target outlet air temperature standard value is determined based on an outlet air temperature standard table, which includes the outlet air temperature standard values of the exhaust gas recirculation cooler when the engine is running under different values of the target operating parameters.
2. The diagnostic method for carbon buildup in exhaust gas recirculation coolers according to claim 1, characterized in that, The target operating parameters are selected from various operating parameters of the engine using the controlled variable method. The target operating parameters include ambient temperature, engine coolant temperature, engine intake airflow, engine exhaust temperature, and engine exhaust gas recirculation rate.
3. The diagnostic method for carbon buildup in exhaust gas recirculation coolers according to claim 2, characterized in that, The standard table for outlet air temperature is determined in the following manner: Multiple preset values of the ambient temperature, multiple preset values of the water temperature, multiple preset values of the intake air volume, multiple preset values of the exhaust temperature, and multiple preset values of the exhaust gas recirculation rate are obtained. Obtain standard values of outlet temperature under different preset combinations of ambient temperature, water temperature, air inlet flow rate, exhaust temperature and exhaust gas recirculation rate under standard test conditions, and form an initial outlet temperature table. The initial outlet temperature table is interpolated using an interpolation method to obtain the standard outlet temperature table.
4. The diagnostic method for carbon buildup in exhaust gas recirculation coolers according to claim 1, characterized in that, The determination of carbon buildup in the exhaust gas recirculation cooler based on the actual exhaust gas temperature and the target exhaust gas temperature standard value includes: Calculate the first integral value of the actual outlet temperature over time, and the second integral value of the target outlet temperature standard value over time; Calculate the absolute value of the deviation rate between the first integral value and the second integral value; Based on the magnitude of the absolute value, it is determined whether the exhaust gas recirculation cooler has a carbon buildup problem and the degree of carbon buildup.
5. The diagnostic method for carbon buildup in exhaust gas recirculation coolers according to claim 4, characterized in that, The determination of whether the exhaust gas recirculation cooler has carbon buildup and the degree of carbon buildup based on the magnitude of the absolute value includes: If the absolute value is less than or equal to the first threshold, it is determined that the exhaust gas recirculation cooler does not have a carbon buildup problem; If the absolute value is greater than the first threshold and less than the second threshold, it is determined that the exhaust gas recirculation cooler has a carbon buildup problem, and the degree of carbon buildup is the first degree. If the absolute value is greater than or equal to the second threshold, it is determined that the exhaust gas recirculation cooler has a carbon buildup problem, and the degree of carbon buildup is the second degree; the second degree is more severe than the first degree.
6. The diagnostic method for carbon buildup in exhaust gas recirculation coolers according to claim 5, characterized in that, If the degree of carbon buildup is the first degree, the method further includes: Increase the vehicle's state of charge balance point to control engine start-up; After the engine starts, it charges the vehicle's battery pack for a first duration under target operating conditions, and while charging the battery pack, it increases the engine's exhaust gas recirculation rate to a target value. If the charging time for the battery pack is less than the first time, the vehicle is powered off. When the vehicle is powered on again, the engine is controlled to continue charging the battery pack under the target operating condition until the cumulative charging time for the battery pack reaches the first time. While continuing to charge the battery pack, the exhaust gas recirculation rate is increased to the target value.
7. The diagnostic method for carbon buildup in exhaust gas recirculation coolers according to claim 6, characterized in that, If the degree of carbon deposition is the second degree, the method further includes: Increase the vehicle's state of charge balance point to control engine start-up; After the engine starts, it charges the battery pack for a second duration under the target operating condition, and while charging the battery pack, it increases the exhaust gas recirculation rate to the target value; the second duration is longer than the first duration. If the charging time for the battery pack is less than the second duration, the vehicle is powered off. When the vehicle is powered on again, the engine is controlled to continue charging the battery pack under the target operating condition until the cumulative charging time for the battery pack reaches the second duration. While continuing to charge the battery pack, the exhaust gas recirculation rate is increased to the target value.
8. A diagnostic device for carbon buildup problems in exhaust gas recirculation coolers, characterized in that, include: The data acquisition module is used to acquire, after the vehicle is powered on, if the vehicle's engine starts and the engine's exhaust gas recirculation valve is open, the actual value of the engine's target operating parameters, and the actual value of the exhaust gas recirculation cooler's outlet temperature when the engine is running under the actual value of the target operating parameters; the target operating parameters affect the exhaust gas recirculation cooler's outlet temperature. The determination module is used to determine the carbon buildup of the exhaust gas recirculation cooler based on the actual value of the exhaust gas temperature and the target standard value of the exhaust gas temperature. The target standard value of the exhaust gas temperature is the standard value of the exhaust gas temperature of the exhaust gas recirculation cooler when the engine is running at the actual value of the target operating parameters. The target standard value of the exhaust gas temperature is determined based on an exhaust gas temperature standard table, which includes the standard values of the exhaust gas temperature of the exhaust gas recirculation cooler when the engine is running at different values of the target operating parameters.
9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the diagnostic method for carbon buildup problems in the exhaust gas recirculation cooler as described in any one of claims 1 to 7.
10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the diagnostic method for carbon buildup problems in the exhaust gas recirculation cooler as described in any one of claims 1 to 7.