Leakage diagnosis methods, devices, vehicles, and media for DPF regenerative injection systems

Abstract

This invention provides a leak diagnosis method, device, vehicle, and medium for a DPF regeneration injection system, belonging to the field of exhaust gas aftertreatment technology. The DPF regeneration injection system is used to inject fuel into an exhaust gas aftertreatment system, which includes an oxidizing catalyst and a diesel particulate filter connected in sequence. The method includes: obtaining the first inlet temperature of the oxidizing catalyst and the second inlet temperature of the diesel particulate filter; determining whether the temperature difference between the first and second inlet temperatures is greater than a temperature difference threshold; if so, performing leak diagnosis on the DPF regeneration injection system. This invention reduces the number of leak diagnoses, avoids fuel waste and fuel adhesion accumulation in the exhaust gas aftertreatment system, and ensures the safety of the exhaust gas aftertreatment system.

Description

Technical Field

[0001] This invention relates to the field of exhaust gas aftertreatment technology, and specifically to a leak diagnosis method, device, vehicle, and medium for a DPF regeneration injection system. Background Technology

[0002] To address particulate pollution caused by diesel engine exhaust, the diesel particulate filter (DPF) is currently the most effective device for reducing diesel engine particulate emissions. However, with prolonged operation, more and more particulate matter accumulates inside the DPF, affecting not only its capture efficiency but also incomplete fuel combustion in the diesel engine. To address this, a DPF regeneration injection system was proposed. This system injects fuel into the DPF and ignites it to raise its internal temperature, thereby oxidizing and burning the accumulated particulate matter, thus eliminating the accumulated particulate matter and achieving active regeneration of the DPF. However, if a leak occurs in the fuel line of the DPF regeneration injection system, the fuel will rapidly atomize at high temperatures, producing flammable and explosive gases within a certain range, posing a significant danger and potentially even causing vehicle damage.

[0003] To prevent safety accidents, leak detection of the DPF regeneration injection system is necessary. Current detection methods involve introducing fuel into the pressure sensor chamber each time the vehicle is powered on, and checking if the fuel pressure is within a reasonable range to determine if the DPF regeneration injection system is leaking. This method has the following technical problems: 1. Fuel is wasted every time the vehicle is powered on for self-test; 2. After the diagnostic is complete, the fuel in the chamber is directly discharged to the exhaust aftertreatment system. If the exhaust temperature is low at this time, it will adhere to the Diesel Oxidation Catalyst (DOC). If the fuel continues to accumulate and is not removed in time, it will release a large amount of heat during the regeneration process, causing damage to the exhaust aftertreatment system.

[0004] Therefore, there is an urgent need to provide a leak diagnosis method, device, vehicle, and medium for DPF regeneration injection systems, which can reduce fuel waste and mitigate fuel adhesion accumulation while achieving leak diagnosis, thereby ensuring the safety of the exhaust aftertreatment system. Summary of the Invention

[0005] In view of this, it is necessary to provide a leak diagnosis method, device, vehicle and medium for a DPF regeneration injection system to solve the technical problems in the prior art that require fuel to be introduced into the cavity where the pressure sensor is located, resulting in fuel waste and fuel easily adhering and accumulating on DOC, leading to poor safety of the exhaust aftertreatment system.

[0006] On the one hand, to solve the above-mentioned technical problems, the present invention provides a leak diagnosis method for a DPF regeneration injection system. The DPF regeneration injection system is used to inject fuel into an exhaust gas aftertreatment system, which includes an oxidation catalyst and a diesel particulate filter connected in sequence. The method includes:

[0007] The first inlet temperature of the oxidation catalyst and the second inlet temperature of the diesel particulate filter are obtained.

[0008] Determine whether the temperature difference between the first inlet temperature and the second inlet temperature is greater than a temperature difference threshold.

[0009] If so, a leak diagnosis is performed on the DPF regeneration injection system.

[0010] In one possible implementation, before determining whether the temperature difference between the first inlet temperature and the second inlet temperature is greater than a temperature difference threshold, the method further includes:

[0011] The first inlet temperature gradient of the oxidation catalyst and the second inlet temperature gradient of the diesel particulate filter are obtained.

[0012] Determine whether both the first inlet temperature change gradient and the second inlet temperature change gradient are less than the gradient change threshold;

[0013] The step of determining whether the temperature difference between the first inlet temperature and the second inlet temperature is greater than a temperature difference threshold includes:

[0014] When both the first inlet temperature change gradient and the second inlet temperature change gradient are less than the gradient change threshold, it is determined whether the temperature difference between the first inlet temperature and the second inlet temperature is greater than the temperature difference threshold.

[0015] In one possible implementation, before determining whether the temperature difference between the first inlet temperature and the second inlet temperature is greater than a temperature difference threshold, the method further includes:

[0016] Obtain the engine speed change gradient and torque change gradient;

[0017] Determine whether the speed change gradient is less than a speed gradient threshold and whether the torque change gradient is less than a torque gradient threshold;

[0018] The step of determining whether the temperature difference between the first inlet temperature and the second inlet temperature is greater than a temperature difference threshold includes:

[0019] When the speed change gradient is less than the speed gradient threshold and the torque change gradient is less than the torque gradient threshold, it is determined whether the temperature difference between the first inlet temperature and the second inlet temperature is greater than the temperature difference threshold.

[0020] In one possible implementation, before determining whether the temperature difference between the first inlet temperature and the second inlet temperature is greater than a temperature difference threshold, the method further includes:

[0021] Determine whether the first inlet temperature is greater than the combustion set temperature;

[0022] The step of determining whether the temperature difference between the first inlet temperature and the second inlet temperature is greater than a temperature difference threshold includes:

[0023] When the first inlet temperature is greater than the combustion set temperature, it is determined whether the temperature difference between the first inlet temperature and the second inlet temperature is greater than the temperature difference threshold.

[0024] In one possible implementation, the DPF regeneration injection system includes an intake circuit, a fuel inlet circuit, an air exhaust valve disposed on the intake circuit, a fuel shut-off valve and a diesel metering valve disposed on the fuel inlet circuit, and a pressure sensor connecting the fuel shut-off valve and the diesel metering valve.

[0025] The leak diagnosis of the DPF regeneration injection system includes:

[0026] The diesel metering valve and the fuel shut-off valve are controlled to close, and the air exhaust valve is opened. The first pressure value collected by the pressure sensor is obtained, and it is determined whether the first pressure value is greater than the pressure threshold. If it is, the diesel metering valve is determined to be leaking; if not, the diesel metering valve is determined to be leak-free.

[0027] The diesel metering valve, the fuel shut-off valve, and the air exhaust valve are controlled to close. A second pressure value collected by the pressure sensor is obtained. It is determined whether the second pressure value is greater than a pressure threshold. If it is, the fuel shut-off valve is determined to be leaking. If not, the fuel shut-off valve is determined to be leak-free.

[0028] In one possible implementation, after performing leak diagnosis on the DPF regeneration injection system, the following is also included:

[0029] Keep the fuel shut-off valve and the air exhaust valve closed, open the diesel metering valve, and close the diesel metering valve when the opening time of the diesel metering valve is equal to the preset time.

[0030] In one possible implementation, the DPF regeneration injection system further includes a nozzle disposed on the side of the diesel metering valve away from the fuel shut-off valve. After performing leak diagnosis on the DPF regeneration injection system, the system further includes:

[0031] Keep the diesel metering valve and the fuel shut-off valve closed, open the air vent valve, and control the air vent valve to intermittently purge the pipeline between the diesel metering valve and the nozzle.

[0032] On the other hand, the present invention also provides a leak diagnosis device for a DPF regeneration injection system. The DPF regeneration injection system is used to inject fuel into an exhaust aftertreatment system, the exhaust aftertreatment system including an oxidation catalyst and a diesel particulate filter connected in sequence; the device includes:

[0033] A temperature acquisition unit is used to acquire the first inlet temperature of the oxidation catalyst and the second inlet temperature of the diesel particulate filter.

[0034] A temperature difference judgment unit is used to determine whether the temperature difference between the first inlet temperature and the second inlet temperature is greater than a temperature difference threshold.

[0035] The leakage diagnosis unit is used to perform leakage diagnosis on the DPF regeneration injection system when the temperature difference between the first inlet temperature and the second inlet temperature is greater than the temperature difference threshold.

[0036] On the other hand, the present invention also provides a vehicle including a memory and a processor, wherein,

[0037] The memory is used to store programs;

[0038] The processor, coupled to the memory, is used to execute the program stored in the memory to implement the steps in the leak diagnosis method for the DPF regeneration injection system described in any of the above possible implementations.

[0039] On the other hand, the present invention also provides a computer-readable storage medium storing a program or instructions that, when executed by a processor, implement the steps in the leak diagnosis method for the DPF regenerative injection system described in any of the above possible implementations.

[0040] The beneficial effects of this invention are as follows: The leak diagnosis method for the DPF regeneration injection system provided by this invention determines the presence of a leak risk based on the temperature difference between the first inlet temperature of the oxidizing catalyst and the second inlet temperature of the diesel particulate filter before performing leak diagnosis. Leak diagnosis of the DPF regeneration injection system is only performed when a leak risk is identified. This eliminates the need for leak diagnosis of the DPF regeneration injection system every time the vehicle is powered on, reducing the number of leak diagnoses and consequently reducing the number of times fuel is introduced into the cavity where the pressure sensor is located, thus avoiding fuel waste. Furthermore, the reduction in the number of leaks slows down fuel accumulation, mitigating safety risks to the exhaust aftertreatment system to some extent and ensuring the safety of the exhaust aftertreatment system. Attached Figure Description

[0041] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0042] Figure 1 A schematic diagram of an embodiment of an exhaust gas aftertreatment system;

[0043] Figure 2 A schematic flowchart of an embodiment of the leak diagnosis method for the DPF regeneration injection system provided by the present invention;

[0044] Figure 3 This is a schematic flowchart of an embodiment of the present invention for determining temperature gradient changes;

[0045] Figure 4 This is a schematic flowchart of an embodiment of the present invention for determining changes in engine operating conditions;

[0046] Figure 5 A schematic diagram of an embodiment of a DPF regeneration injection system;

[0047] Figure 6 For the present invention Figure 1 A schematic flowchart of an embodiment of step S103;

[0048] Figure 7 A schematic diagram of an embodiment of the leak diagnosis device for the DPF regeneration injection system provided by the present invention;

[0049] Figure 8 A schematic diagram of an embodiment of the vehicle provided by the present invention. Detailed Implementation

[0050] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0051] It should be understood that the illustrative drawings are not drawn to scale. The flowcharts used in this invention illustrate operations implemented according to some embodiments of the invention. It should be understood that the operations in the flowcharts may be implemented out of order, and steps without logical contextual relationships may be reversed or performed simultaneously. Furthermore, those skilled in the art, guided by the content of this invention, may add one or more other operations to the flowcharts, or remove one or more operations from the flowcharts. Some block diagrams shown in the drawings are functional entities and do not necessarily correspond to physically or logically independent entities. These functional entities may be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor systems and / or microcontroller systems.

[0052] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0053] This invention provides a leak diagnosis method, device, vehicle, and medium for a DPF regeneration injection system, which are described below.

[0054] Before demonstrating specific embodiments, the exhaust aftertreatment system will be introduced first, such as... Figure 1 As shown, the exhaust aftertreatment system includes a diesel oxidation catalyst (DOC), a diesel particulate filter (DPF), and a selective catalytic reduction (SCR) or an ammonia slip catalyst (ASC) connected in sequence.

[0055] DOC has three main functions: 1. Reduce hydrocarbon (HC) emissions: oxidize unburned HC in the exhaust gas into H2O and CO2; 2. Oxidize NO into NO2; 3. Oxidize fuel injected into the exhaust pipe.

[0056] DPF is mainly used to capture particulate matter in exhaust gases to meet the particulate quantity requirements of China VI emission standards.

[0057] The function of SCR is to: inject urea solution into the exhaust pipe and hydrolyze it into NH3; then, in the SCR process, NO in the exhaust gas is removed. x It is reduced to non-toxic nitrogen gas N2.

[0058] The function of ASC is to eliminate excess or escaped NH3, oxidizing excess NH3 into N2, N2O, and NO. x Simultaneously, recatalyze NO x NH3 reacts to produce nitrogen gas (N2).

[0059] And, as Figure 1 As shown, one end of the DPF regeneration injection system is used to supply fuel, and the other end is connected to the exhaust aftertreatment system to inject fuel into the exhaust aftertreatment system, where the fuel burns off the carbon particles in the DPF.

[0060] This invention provides a leak diagnosis method for a DPF regenerative injection system, such as... Figure 2 As shown, the leakage diagnosis method for the DPF regeneration injection system includes:

[0061] S201, Obtain the first inlet temperature of the oxidation catalyst and the second inlet temperature of the diesel particulate filter;

[0062] S202. Determine whether the temperature difference between the first inlet temperature and the second inlet temperature is greater than the temperature difference threshold.

[0063] S203. If so, then perform a leak diagnosis on the DPF regeneration injection system.

[0064] In step S201, the first inlet temperature and the second inlet temperature are obtained by collecting the first inlet temperature and the second inlet temperature based on temperature sensors installed at the inlet of the oxidation catalyst and the inlet of the diesel particulate filter.

[0065] It should be noted that the accuracy of the first inlet temperature and the second inlet temperature is crucial for the subsequent assessment of leakage risk. Therefore, it is necessary to ensure that the temperature sensor is fault-free before performing step S201.

[0066] It should be understood that if the temperature difference between the first temperature inlet and the second temperature inlet is less than or equal to the temperature difference threshold, it indicates that there is no risk of leakage and there is no need to perform leakage diagnosis on the DPF regeneration injection system.

[0067] The principle behind determining the risk of leakage based on the temperature difference between the first and second inlet temperatures is as follows: Figure 1As can be seen, the DPF regeneration injection system is located upstream of the DOC. If a fuel leak occurs, the fuel will oxidize within the DOC at suitable temperatures, generating heat. This heat is transferred to the DPF inlet with the exhaust gas, causing the DPF inlet temperature to rise. Therefore, when the temperature difference between the DPF inlet and the DOC inlet exceeds a limit, a leak risk is identified. This approach aims to reduce the number of diagnostic attempts while ensuring timely detection of leaks.

[0068] Compared with existing technologies, the leak diagnosis method for the DPF regeneration injection system provided in this invention first determines the presence of a leak risk based on the temperature difference between the first inlet temperature of the oxidizing catalyst and the second inlet temperature of the diesel particulate filter before performing leak diagnosis. Leak diagnosis of the DPF regeneration injection system is only performed when a leak risk is identified. This eliminates the need for leak diagnosis every time the vehicle is powered on, reducing the number of leak diagnoses and consequently reducing the number of times fuel is introduced into the cavity where the pressure sensor is located, thus avoiding fuel waste. Furthermore, the reduced number of leaks slows down fuel accumulation, mitigating safety risks to the exhaust aftertreatment system to some extent and ensuring its safety.

[0069] Furthermore, such as Figure 1 As shown, there is a DOC (Discharge Occurrence) between the first inlet temperature and the second inlet temperature, which has a significant filtering effect on temperature. That is, when the engine exhaust temperature changes, the first inlet temperature changes first, while the change in the second inlet temperature is delayed. To avoid this delay, which could lead to inaccurate risk assessment based on the obtained first and second inlet temperatures, in some embodiments of the present invention, such as... Figure 3 As shown, before step S202, the procedure further includes:

[0070] S301, Obtain the first inlet temperature gradient of the oxidation catalyst and the second inlet temperature gradient of the diesel particulate filter;

[0071] S302. Determine whether the first inlet temperature change gradient and the second inlet temperature change gradient are both less than the gradient change threshold.

[0072] Then step S202 is as follows:

[0073] When both the first inlet temperature change gradient and the second inlet temperature change gradient are less than the gradient change threshold, determine whether the temperature difference between the first inlet temperature and the second inlet temperature is greater than the temperature difference threshold.

[0074] This invention, by setting a threshold where both the first and second inlet temperature change gradients are less than a gradient change threshold, determines whether the temperature difference between the first and second inlet temperatures exceeds a temperature difference threshold. This avoids the temperature delay caused by DOC filtering affecting the accuracy of the temperature difference, eliminates the impact of temperature delay, ensures the accuracy of the temperature difference between the first and second inlet temperatures, improves the accuracy of filtering risk assessment, and further reduces the number of leak diagnosis attempts.

[0075] Since significant changes in the engine's operating conditions can also cause significant changes in the engine exhaust temperature, to avoid this affecting the accuracy of leak diagnosis timing, in some embodiments of the present invention, such as... Figure 4 As shown, before step S202, the procedure further includes:

[0076] S401, Obtain the engine speed change gradient and torque change gradient;

[0077] S402. Determine whether the speed change gradient is less than the speed gradient threshold and whether the torque change gradient is less than the torque gradient threshold.

[0078] Then step S202 is as follows:

[0079] When the speed change gradient is less than the speed gradient threshold and the torque change gradient is less than the torque gradient threshold, determine whether the temperature difference between the first inlet temperature and the second inlet temperature is greater than the temperature difference threshold.

[0080] This invention, by judging the speed change gradient and torque change gradient, ensures that the engine operating conditions have not changed significantly when the first inlet temperature and the second inlet temperature are obtained, thus avoiding the influence of the engine operating conditions on the first inlet temperature and the second inlet temperature, and further ensuring the accuracy of the judgment of the timing of leakage diagnosis.

[0081] Furthermore, since fuel can only burn at a certain temperature, to ensure complete combustion of the fuel and thus transfer heat to the DPF inlet, in some embodiments of the present invention, before step S202, the following steps are also included:

[0082] Determine if the first inlet temperature is greater than the combustion set temperature;

[0083] Then step S202 is as follows:

[0084] When the first inlet temperature is greater than the combustion set temperature, determine whether the temperature difference between the first inlet temperature and the second inlet temperature is greater than the temperature difference threshold.

[0085] Before determining the temperature difference, this embodiment of the invention ensures that the first inlet temperature is greater than the combustion set temperature, which guarantees that the fuel injected into the exhaust aftertreatment system has been fully burned. The temperature difference is generated by the combustion of fuel, which further ensures the accuracy of the timing of leak diagnosis.

[0086] In specific embodiments of the present invention, such as Figure 5 As shown, the DPF regeneration injection system includes an intake circuit, an oil inlet circuit, an air exhaust valve installed on the intake circuit, a fuel cut-off valve and a diesel metering valve installed on the oil inlet circuit, and a pressure sensor connecting the fuel cut-off valve and the diesel metering valve. The intake circuit is used to introduce air, the oil inlet circuit is used to introduce fuel, and the end point of the oil inlet circuit is the nozzle.

[0087] It should be noted that the DPF regeneration injection system may also include other control valves, which will not be elaborated here.

[0088] Based on the above-described DPF regeneration injection system, in some embodiments of the present invention, such as Figure 6 As shown, step S103 includes:

[0089] S601: Control the diesel metering valve and fuel shut-off valve to close, and the air exhaust valve to open. Obtain the first pressure value collected by the pressure sensor. Determine whether the first pressure value is greater than the pressure threshold. If yes, determine that the diesel metering valve is leaking. If no, determine that the diesel metering valve is not leaking.

[0090] S602: Control the diesel metering valve, fuel shut-off valve and air exhaust valve to close, obtain the second pressure value collected by the pressure sensor, and determine whether the second pressure value is greater than the pressure threshold. If it is, determine that the fuel shut-off valve is leaking; if not, determine that the fuel shut-off valve is not leaking.

[0091] It should be noted that if a leak is detected in the fuel shut-off valve and / or diesel metering valve, a fault alarm message will be generated to alert staff and prompt them to take action.

[0092] This invention enables leak diagnosis of the diesel metering valve and fuel shut-off valve based on pressure values ​​collected by pressure sensors by controlling the opening and closing of the diesel metering valve, fuel shut-off valve, and air exhaust valve. The diagnostic process is simple and improves the efficiency of leak diagnosis.

[0093] Since fuel needs to be introduced into the oil chamber where the pressure sensor is located during leak diagnosis, and the fuel needs to be drained after the diagnosis is completed, in some embodiments of the present invention, after step S602, the leak diagnosis method for the DPF regeneration injection system further includes:

[0094] Keep the fuel shut-off valve and air exhaust valve closed, open the diesel metering valve, and close the diesel metering valve when the opening time of the diesel metering valve is equal to the preset time.

[0095] In this embodiment of the invention, the fuel in the oil chamber is discharged by opening the diesel metering valve for a preset time.

[0096] The preset duration can be adaptively set according to the amount of fuel introduced, and no specific limitation is made here.

[0097] like Figure 5 As shown, the DPF regeneration injection system also includes a nozzle located on the side of the diesel metering valve away from the fuel shut-off valve. After the diagnosis is completed, fuel is discharged to the exhaust aftertreatment system through the nozzle. Some fuel will remain on the nozzle, and fuel easily adsorbs carbon soot particles in the exhaust. Over time, this will cause nozzle blockage. To avoid nozzle blockage, in some embodiments of the present invention, after step S203, the leak diagnosis method of the DPF regeneration injection system further includes:

[0098] Keep the diesel metering valve and fuel shut-off valve closed, open the air vent valve, and control the air vent valve to intermittently purge the pipeline between the diesel metering valve and the nozzle.

[0099] This invention adds a purging function to purge the fuel in the pipeline between the diesel metering valve and the nozzle, thereby preventing fuel adhesion and reducing the risk of nozzle blockage.

[0100] To better implement the leak diagnosis method for the DPF regeneration injection system in this embodiment of the invention, based on the leak diagnosis method for the DPF regeneration injection system, this embodiment of the invention also provides a leak diagnosis device for the DPF regeneration injection system. The DPF regeneration injection system is used to inject fuel into an exhaust aftertreatment system, which includes an oxidation catalyst and a diesel particulate filter connected in sequence. Figure 7 As shown, the leak diagnosis device 700 for the DPF regeneration injection system includes:

[0101] Temperature acquisition unit 701 is used to acquire the first inlet temperature of the oxidation catalyst and the second inlet temperature of the diesel particulate filter.

[0102] The temperature difference judgment unit 702 is used to determine whether the temperature difference between the first inlet temperature and the second inlet temperature is greater than the temperature difference threshold.

[0103] Leakage diagnosis unit 703 is used to perform leak diagnosis on the DPF regeneration injection system when the temperature difference between the first inlet temperature and the second inlet temperature is greater than the temperature difference threshold.

[0104] It should be noted that the leakage diagnosis device 700 of the DPF regeneration injection system provided in the above embodiments can realize the technical solutions described in the above embodiments of the leakage diagnosis method of the DPF regeneration injection system. The specific implementation principles or implementation details of each module or unit can be found in the corresponding content of the above embodiments of the leakage diagnosis method of the DPF regeneration injection system, which will not be elaborated here.

[0105] like Figure 8 As shown, the present invention also provides a vehicle 800. The vehicle 800 includes a processor 801, a memory 802, and a display 803. Figure 8 Only some components of vehicle 800 are shown, but it should be understood that it is not required to implement all of the components shown, and more or fewer components may be implemented instead.

[0106] In some embodiments, processor 801 is an electronic control unit (ECU) in vehicle 800, used to run program code or process data stored in memory 802, such as the leak diagnosis method for DPF regenerative injection system in this invention.

[0107] In some embodiments, memory 802 may be an internal storage unit of vehicle 800, such as hard disk or memory of vehicle 800.

[0108] Furthermore, the memory 802 may include both internal storage units of the vehicle 800 and external storage devices. The memory 802 is used to store application software and various types of data installed on the vehicle 800.

[0109] In some embodiments, display 803 may be an LED display, a liquid crystal display, a touch-sensitive liquid crystal display, or an OLED (Organic Light-Emitting Diode) touchscreen. Display 803 is used to display information about vehicle 800 and to display a visual user interface. Components 801-803 of vehicle 800 communicate with each other via a system bus.

[0110] In some embodiments of the present invention, when the processor 801 executes the leak diagnosis program for the DPF regenerative injection system in the memory 802, the following steps can be implemented:

[0111] The first inlet temperature of the oxidation catalyst and the second inlet temperature of the diesel particulate filter are obtained.

[0112] Determine whether the temperature difference between the first inlet temperature and the second inlet temperature is greater than the temperature difference threshold.

[0113] If so, then perform a leak diagnosis on the DPF regeneration injection system.

[0114] It should be understood that when the processor 801 executes the leak diagnosis program for the DPF regeneration injection system in the memory 802, in addition to the functions mentioned above, it can also perform other functions, as detailed in the description of the corresponding method embodiments above.

[0115] Accordingly, embodiments of the present invention also provide a computer-readable storage medium for storing computer-readable programs or instructions. When the programs or instructions are executed by a processor, they can implement the steps or functions in the leak diagnosis method of the DPF regeneration injection system provided in the above-described method embodiments.

[0116] Those skilled in the art will understand that all or part of the processes of the methods described in the above embodiments can be implemented by a computer program instructing related hardware (such as a processor, controller, etc.), and the computer program can be stored in a computer-readable storage medium. The computer-readable storage medium may be a disk, optical disk, read-only memory, or random access memory, etc.

[0117] The above provides a detailed description of the leakage diagnosis method, device, vehicle, and medium for a DPF regeneration injection system provided by the present invention. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A leak diagnosis method for a DPF regeneration injection system, characterized in that, The DPF regeneration injection system is used to inject fuel into an exhaust aftertreatment system, the exhaust aftertreatment system comprising an oxidation catalyst and a diesel particulate filter connected in sequence; the method includes: The first inlet temperature of the oxidation catalyst and the second inlet temperature of the diesel particulate filter are obtained. The first inlet temperature gradient of the oxidation catalyst and the second inlet temperature gradient of the diesel particulate filter are obtained. Determine whether both the first inlet temperature change gradient and the second inlet temperature change gradient are less than the gradient change threshold; Obtain the engine speed change gradient and torque change gradient; Determine whether the speed change gradient is less than a speed gradient threshold and whether the torque change gradient is less than a torque gradient threshold; Determine whether the first inlet temperature is greater than the combustion set temperature; When the first inlet temperature change gradient and the second inlet temperature change gradient are both less than the gradient change threshold, the speed change gradient is less than the speed gradient threshold, the torque change gradient is less than the torque gradient threshold, and the first inlet temperature is greater than the combustion set temperature, determine whether the temperature difference between the first inlet temperature and the second inlet temperature is greater than the temperature difference threshold. If so, a leak diagnosis is performed on the DPF regeneration injection system.

2. The leakage diagnosis method for the DPF regeneration injection system according to claim 1, characterized in that, The DPF regeneration injection system includes an intake circuit, an oil intake circuit, an air exhaust valve installed on the intake circuit, a fuel cut-off valve and a diesel metering valve installed on the oil intake circuit, and a pressure sensor connected to the fuel cut-off valve and the diesel metering valve. The leak diagnosis of the DPF regeneration injection system includes: The diesel metering valve and the fuel shut-off valve are controlled to close, and the air exhaust valve is opened. The first pressure value collected by the pressure sensor is obtained, and it is determined whether the first pressure value is greater than the pressure threshold. If it is, the diesel metering valve is determined to be leaking; if not, the diesel metering valve is determined to be leak-free. The diesel metering valve, the fuel shut-off valve, and the air exhaust valve are controlled to close. A second pressure value collected by the pressure sensor is obtained. It is determined whether the second pressure value is greater than a pressure threshold. If it is, the fuel shut-off valve is determined to be leaking. If not, the fuel shut-off valve is determined to be leak-free.

3. The leakage diagnosis method for the DPF regeneration injection system according to claim 2, characterized in that, Following the leak diagnosis of the DPF regeneration injection system, the following is also included: Keep the fuel shut-off valve and the air exhaust valve closed, open the diesel metering valve, and close the diesel metering valve when the opening time of the diesel metering valve is equal to the preset time.

4. The leakage diagnosis method for the DPF regeneration injection system according to claim 3, characterized in that, The DPF regeneration injection system also includes a nozzle disposed on the side of the diesel metering valve away from the fuel shut-off valve. Therefore, after performing leak diagnosis on the DPF regeneration injection system, it further includes: Keep the diesel metering valve and the fuel shut-off valve closed, open the air vent valve, and control the air vent valve to intermittently purge the pipeline between the diesel metering valve and the nozzle.

5. A leak diagnosis device for a DPF regeneration injection system, characterized in that, A leak diagnosis method for a DPF regeneration injection system according to any one of claims 1 to 4, wherein the DPF regeneration injection system is used to inject fuel into an exhaust aftertreatment system, the exhaust aftertreatment system comprising an oxidation catalyst and a diesel particulate filter connected in sequence; the device comprises: A temperature acquisition unit is used to acquire the first inlet temperature of the oxidation catalyst and the second inlet temperature of the diesel particulate filter. A temperature difference judgment unit is used to determine whether the temperature difference between the first inlet temperature and the second inlet temperature is greater than a temperature difference threshold. The leakage diagnosis unit is used to perform leakage diagnosis on the DPF regeneration injection system when the temperature difference between the first inlet temperature and the second inlet temperature is greater than the temperature difference threshold.

6. A vehicle, characterized in that, Including memory and processor, among which, The memory is used to store programs; The processor, coupled to the memory, is used to execute the program stored in the memory to implement the steps in the leak diagnosis method for the DPF regeneration injection system according to any one of claims 1 to 4.

7. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a program or instructions that, when executed by a processor, implement the steps in the leak diagnosis method for the DPF regenerative injection system according to any one of claims 1 to 4.

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