Method and device for diagnosing urea system leakage fault, vehicle and storage medium

Abstract

The application discloses a urea system liquid leakage fault diagnosis method and device, a vehicle and a storage medium. The method comprises the following steps: when it is determined that a urea system has a liquid leakage fault, controlling a urea pump of the urea system to stop running and controlling a urea nozzle to be closed; acquiring a pressure change value of a urea conveying pipe of the urea system; and determining a fault type of the urea system liquid leakage according to a first pressure change value of the urea conveying pipe within a first preset time. When it is determined that the urea system has the liquid leakage fault, the fault type of the urea system liquid leakage can be identified by controlling the running of the urea pump, the opening and closing of the nozzle and judging the change of the pressure of the urea conveying pipe of the urea system, so that the user can be reminded to check in time before the urea in the urea system leaks too much, the problem that the vehicle cannot be started due to too much urea leakage is avoided, and the reliability of the vehicle is improved.

Description

Technical Field

[0001] This invention relates to the field of vehicle technology, and in particular to a method, apparatus, vehicle, and storage medium for diagnosing urea system leakage faults. Background Technology

[0002] With the development of vehicle technology and the increasing environmental protection requirements, automotive urea in vehicle urea systems is widely used because it can neutralize nitrogen oxides in diesel vehicles, ensuring that exhaust emissions meet standards. Moreover, the use of automotive urea as a diesel vehicle exhaust treatment fluid is one of the effective technical measures for diesel vehicles in my country to meet the National IV and above emission regulations.

[0003] Currently, the main components of a urea system are: injection structure (nozzle), delivery structure (delivery pipe), storage structure (urea tank), control structure (controller unit, DCU), and execution structure (urea pump). In existing technologies, when a leak is detected in a conventional urea system, there is no specific method for identifying the leak, making it difficult to correctly pinpoint the cause of the malfunction. This can easily lead to excessive leakage of urea solution, resulting in the vehicle being unable to start. Therefore, correctly identifying the cause of a urea system leak is a problem that urgently needs to be solved. Summary of the Invention

[0004] The present invention aims to at least solve one of the technical problems existing in the prior art. Therefore, the object of the present invention is to provide a method, apparatus, vehicle, and storage medium for diagnosing urea system leakage faults.

[0005] The present invention proposes a diagnostic method for urea system leakage faults, the method comprising: when it is determined that a leakage fault has occurred in the urea system, controlling the urea pump of the urea system to stop running and controlling the urea nozzle to close; acquiring the pressure change value of the urea delivery pipe of the urea system; and determining the fault type of the urea system leakage fault based on the first pressure change value of the urea delivery pipe within a first preset time.

[0006] In addition, the diagnostic method for urea system leakage faults according to embodiments of the present invention may also have the following additional technical features:

[0007] Further, determining that a urea system has experienced a leakage fault includes: acquiring the change in urea volume in the urea tank and the total amount of urea consumed; and determining that the urea system has experienced a leakage fault when the difference between the change in urea volume and the total amount of urea consumed is greater than a preset volume within a second preset time period, wherein the second preset time period is longer than the first preset time period.

[0008] Further, determining the urea system leakage fault type based on the first pressure change value of the urea delivery pipe within a first preset time period includes: determining that the urea tank has leaked when the first pressure change value is not greater than a first preset pressure threshold, wherein the first pressure change value is the pressure change value of the urea delivery pipe within the first preset time period when the urea nozzle is in the closed state; and determining the urea system leakage fault type based on the second pressure change value of the urea delivery pipe within a third preset time period when the first pressure change value is greater than the first preset pressure threshold, wherein the second pressure change value is the pressure change value of the urea delivery pipe within the third preset time period when the urea nozzle is in the closed state, and the third preset time period is less than the first preset time period.

[0009] Further, the fault type of leakage in the urea system is determined based on the second pressure change value of the urea delivery pipe within a third preset time period, including: when the second pressure change value is greater than a second preset pressure threshold, it is determined that the urea delivery pipe has a leakage fault, wherein the second preset pressure threshold is greater than the first preset pressure threshold.

[0010] Furthermore, determining the urea system leakage fault type based on the second pressure change value of the urea delivery pipe within a third preset time period also includes: determining that the urea nozzle has a normally open fault when the second pressure change value is equal to the second preset pressure threshold.

[0011] Further, determining the urea system leakage fault type based on the second pressure change value of the urea delivery pipe within a third preset time period also includes: when the second pressure change value is less than the second preset pressure threshold, controlling the urea nozzle to open, and determining the urea system leakage fault type based on the third pressure change value of the urea delivery pipe within the third preset time period, wherein the third pressure change value is the pressure change value corresponding to the urea delivery pipe within the third preset time period when the urea nozzle is in the open state.

[0012] Further, the fault type of leakage in the urea system is determined based on the third pressure change value of the urea delivery pipe within the third preset time period, including: when the third pressure change value is equal to the sum of the second pressure change value and the second preset pressure threshold, it is determined that the urea delivery pipe has a leakage fault; when the third pressure change value is not equal to the sum of the second pressure change value and the second preset pressure threshold, it is determined that the urea nozzle has a partial jamming fault or the urea delivery pipe has a leakage fault.

[0013] According to the diagnostic method for urea system leakage faults according to embodiments of the present invention, when a urea system leakage fault is determined, the type of urea system leakage fault can be identified by controlling the operation of the urea pump, the opening and closing of the nozzle, and judging the pressure changes of the urea delivery pipe of the urea system. This allows the user to be reminded to check in time before the urea leakage in the urea system becomes excessive, thereby avoiding the problem of the vehicle being unable to start due to excessive urea leakage and improving the reliability of the vehicle.

[0014] To address the aforementioned problems, this invention also proposes a diagnostic device for urea system leakage faults, comprising: a control module, used to control the urea pump of the urea system to stop operating and control the urea nozzle to close when a leakage fault is determined to occur in the urea system; an acquisition module, used to acquire the pressure change value of the urea delivery pipe of the urea system; and a determination module, used to determine the fault type of the urea system leakage based on the pressure change value of the urea delivery pipe within a first preset time period.

[0015] According to the diagnostic device for urea system leakage faults according to embodiments of the present invention, when a urea system leakage fault is determined, the device can identify the type of urea system leakage fault by controlling the operation of the urea pump, the opening and closing of the nozzle, and judging the pressure changes of the urea delivery pipe of the urea system. This allows the user to be reminded to check in time before the urea leakage in the urea system becomes excessive, thus avoiding the problem of the vehicle being unable to start due to excessive urea leakage and improving the reliability of the vehicle.

[0016] To address the aforementioned problems, the present invention also proposes a vehicle comprising: a urea system; and a diagnostic device for urea system leakage faults as described in any of the above embodiments.

[0017] According to an embodiment of the present invention, when a urea system leak is detected, the type of urea system leak can be identified by controlling the operation of the urea pump, the opening and closing of the nozzle, and judging the pressure changes in the urea delivery pipe of the urea system. This allows the user to be reminded to check in time before the urea leak becomes too large, thus avoiding the problem of the vehicle being unable to start due to excessive urea leakage and improving the reliability of the vehicle.

[0018] To address the aforementioned problems, the present invention also proposes a computer-readable storage medium storing a diagnostic program for urea system leakage faults. When the diagnostic program for urea system leakage faults is executed by a processor, it implements the diagnostic method for urea system leakage faults as described in any of the above embodiments.

[0019] According to an embodiment of the present invention, when a diagnostic program for urea system leakage fault stored thereon is executed by a processor, when a urea system leakage fault is determined, the type of urea system leakage fault can be identified by controlling the operation of the urea pump, the opening and closing of the nozzle, and judging the pressure changes of the urea delivery pipe of the urea system. This alerts the user to check in time before the urea leakage in the urea system becomes excessive, avoiding vehicle starting problems caused by excessive urea leakage, thereby improving vehicle reliability.

[0020] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0021] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0022] Figure 1 This is a schematic diagram of the structure of a urea system according to an embodiment of the present invention;

[0023] Figure 2 This is a flowchart illustrating a method for diagnosing urea system leakage faults according to an embodiment of the present invention.

[0024] Figure 3 This is an overall flowchart of a method for diagnosing urea system leakage faults according to an embodiment of the present invention;

[0025] Figure 4 This is a schematic diagram of a diagnostic device for urea system leakage faults according to an embodiment of the present invention. Detailed Implementation

[0026] The embodiments of the present invention are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. The embodiments of the present invention are described in detail below.

[0027] First, combine Figure 1 A schematic diagram illustrating the structure of the urea system according to an embodiment of the present invention is shown below. Figure 1As shown, the urea system mainly includes: an injection structure (nozzle), a delivery structure (urea delivery pipe), a storage structure (urea tank), a control structure (ECU (Engine Control Unit) and DCU (Data Control Unit)), an execution structure (urea pump), a pump core, a pressure sensor, a vent valve, and an exhaust system. The vent valve is used for waterproofing and ventilation to ensure stable pressure in the urea tank. The pressure sensor is located on the urea delivery pipe to detect pressure changes within the pipe. Specifically, the ECU sends a urea injection demand signal to the DCU. Based on this signal, the DCU controls the operation of the urea pump and the opening and closing of the nozzles, delivering the urea stored in the tank through the delivery pipe to the exhaust system to neutralize nitrogen oxides in diesel vehicles, ensuring emissions meet standards.

[0028] The following is for reference. Figures 2-4 A method, apparatus, vehicle, and storage medium for diagnosing urea system leakage faults according to embodiments of the present invention are described.

[0029] Figure 2 This is a schematic flowchart of a method for diagnosing urea system leakage faults according to an embodiment of the present invention. Figure 2 As shown, a diagnostic method for urea system leakage includes the following steps:

[0030] Step S1: When a leak is detected in the urea system, the urea pump in the urea system is stopped, and the urea nozzle is closed.

[0031] Specifically, in a vehicle's urea system, when a leak is detected, the first step is to stop the urea pump, thus halting urea output from the urea tank to prevent further leakage. The urea nozzles are then closed to create a relatively sealed urea delivery pipe, facilitating the diagnosis of the urea system leak.

[0032] Step S2: Obtain the pressure change value of the urea delivery pipe of the urea system.

[0033] Specifically, when a leak is detected in the vehicle's urea system, and the urea pump and urea nozzles are shut down, the pressure change in the urea delivery pipe can be obtained. This can be achieved, including but not limited to obtaining the pressure change through pressure sensors. Specifically, pressure sensors can be installed at different locations on the urea delivery pipe. These sensors can detect pressure changes at different points within the pipe and output the results, thus helping to determine the location and type of the leak.

[0034] Step S3: Determine the type of urea system leakage based on the first pressure change value of the urea delivery pipe within the first preset time.

[0035] Specifically, under normal circumstances, when the urea pump stops running and the urea nozzle is closed, the pressure change in the urea delivery pipe will remain within a stable range for a preset time. However, when a leakage fault occurs, the pressure changes in the urea delivery pipe will vary depending on the type of fault. Therefore, by comparing the actual detected pressure change with the normal pressure change range within the preset time, the type of urea system leakage fault can be determined. Specifically, after controlling the urea pump to stop running and the urea nozzle to close, the first pressure change value of the urea delivery pipe within the first preset time is obtained. The type of urea system leakage fault can be determined based on this first pressure change value within the first preset time. That is, the type of urea system leakage fault is determined by analyzing and judging the characteristics of the first pressure change value within the first preset time. The first preset time can be a pre-set threshold, which can be set according to actual conditions and experimental data and stored in the controller. Understandably, when a leak is detected in the urea system, the pressure in the urea delivery pipe will change significantly within a short period after the urea pump stops operating and the urea nozzle is closed. Therefore, to improve the accuracy of pressure change measurement, the first preset time can be set shorter based on actual conditions and experimental data. For example, the first preset time is 30 seconds.

[0036] In summary, according to the diagnostic method for urea system leakage faults according to embodiments of the present invention, when a urea system leakage fault is determined, the type of urea system leakage fault can be identified by controlling the operation of the urea pump, the opening and closing of the nozzle, and judging the pressure changes in the urea delivery pipe of the urea system. This allows the user to be reminded to check in time before a significant amount of urea leaks from the urea system, thus avoiding vehicle starting problems caused by excessive urea leakage and improving vehicle reliability.

[0037] In one embodiment of the present invention, determining that a urea system has leaked includes: acquiring the change in urea volume in the urea tank and the total amount of urea consumed; and determining that a urea system has leaked when the difference between the change in urea volume and the total amount of urea consumed is greater than a preset volume within a second preset time period, wherein the second preset time period is greater than the first preset time period.

[0038] Specifically, the change in urea volume in the urea tank over a certain period of time can be monitored and acquired in real time by a level sensor integrated on the urea pump, and the total urea consumption can be calculated cumulatively by the data control unit (DCU). In determining whether a urea system leak has occurred, the change in urea volume over a certain period of time can be compared with the total urea consumption. Specifically, within a second preset time period, if the change in urea volume in the urea tank minus the total urea consumption exceeds a preset volume, a leak in the urea system can be confirmed. The preset volume and the second preset time can be pre-set thresholds, which can be set according to actual conditions and experimental data and stored in the controller. It is understandable that when the urea system leaks slowly, the change in urea volume in the urea tank is not significant, and the level sensor's error in detecting the change in urea volume in a short time is relatively large. In practical applications, the second preset time can be set to be longer to improve the accuracy of the detection results of the change in urea volume in the urea tank. For example, the second preset time is half an hour.

[0039] In a specific embodiment, when the difference between the change in urea volume collected by the level sensor and the total urea consumption calculated by the data control unit (DCU) exceeds 1 liter within half an hour, it is considered that the urea in the urea system is abnormally reduced, and a urea leakage fault is determined to have occurred in the urea system, thus entering the leakage fault diagnosis mode.

[0040] In one embodiment of the present invention, determining the urea system leakage fault type based on a first pressure change value of the urea delivery pipe within a first preset time period includes: determining that a urea tank leakage fault has occurred when the first pressure change value is not greater than a first preset pressure threshold, wherein the first pressure change value is the pressure change value of the urea delivery pipe within the first preset time period when the urea nozzle is in a closed state; and determining the urea system leakage fault type based on a second pressure change value of the urea delivery pipe within a third preset time period when the first pressure change value is greater than the first preset pressure threshold, wherein the second pressure change value is the pressure change value of the urea delivery pipe within the third preset time period when the urea nozzle is in a closed state, and the third preset time period is less than the first preset time period.

[0041] Specifically, when a leak is detected in the urea system, the urea pump is stopped, and the urea nozzles are closed, preventing urea from entering the urea delivery pipe from the urea tank. If the first pressure change in the urea delivery pipe within a first preset time period does not reach a first preset pressure threshold, a leak is considered to have occurred in the urea tank. Further, if the first pressure change in the urea delivery pipe within the first preset time period is greater than the first preset pressure threshold, the leak type can be determined based on the second pressure change in the urea delivery pipe within a third preset time period, where the third preset time period is shorter than the first preset time period. It can be understood that if the first pressure change is greater than the first preset pressure threshold within the first preset time period, it means that the leak type can be determined based on the second pressure change within a smaller time range, i.e., the third preset time period, to improve the accuracy of the leak type determination. The first preset pressure threshold and the third preset time period can be pre-set thresholds, which can be set according to actual conditions and experimental data and stored in the controller. For example, the first preset time period is 30 seconds, and the third preset time period is 10 seconds.

[0042] In a specific embodiment, the first preset time is, for example, 30 seconds, and the first preset pressure threshold is, for example, 0.5 bar. When the urea system enters the leak diagnosis mode, the data control unit (DCU) of the urea system forcibly controls the nozzle to close and the urea pump to stop. The liquid level sensor of the urea system monitors the first pressure change value in real time within 30 seconds, for example, recorded as ΔP1. When ΔP1≤0.5 bar, it is determined that there is no fault in the urea delivery pipe and the nozzle end, and at this time it is determined that the urea tank is leaking.

[0043] In one embodiment of the present invention, determining the urea system leakage fault type based on the second pressure change value of the urea delivery pipe within a third preset time period includes: determining that the urea delivery pipe has a leakage fault when the second pressure change value is greater than a second preset pressure threshold, wherein the second preset pressure threshold is greater than a first preset pressure threshold.

[0044] Specifically, the second preset pressure threshold is the pressure change in the urea delivery pipe when the nozzle experiences a normally open malfunction, and this pressure change is greater than the first preset pressure threshold. When a leak occurs in the urea delivery pipe, the second pressure change exceeds the second preset pressure threshold within a short period. Therefore, the relationship between the second pressure change and the second preset pressure threshold within a third preset time period can be used to determine whether a leak has occurred in the urea delivery pipe. Specifically, when a leak is confirmed in the urea system, the urea pump is stopped, and the urea nozzle is closed. When the urea nozzle is closed, the urea pump stops operating, and urea from the urea tank stops entering the urea delivery pipe. If a leak exists in the urea delivery pipe within the third preset time period, urea will leak, corresponding to an increase in the second pressure change value. That is, if the second pressure change value in the urea delivery pipe within the third preset time period is greater than the second preset pressure threshold, a leak can be identified. It is understood that the third preset time and the second preset pressure threshold can be experimentally calibrated and stored in the controller.

[0045] In a specific embodiment, the first preset time is, for example, 30 seconds, the first preset pressure threshold is, for example, 0.5 bar, the third preset time is, for example, 10 seconds, and the second preset pressure threshold is, for example, 2 bar. When the first pressure change value ΔP1 within 30 seconds is greater than 0.5 bar, the relationship between the second pressure change value ΔP2 within 10 seconds and 2 bar is further determined. When the second pressure change value ΔP2 within 10 seconds is greater than 2 bar, it is determined that a leakage fault has occurred in the urea delivery pipe.

[0046] In one embodiment of the present invention, the method of determining the urea system leakage fault type based on the second pressure change value of the urea delivery pipe within a third preset time period further includes: determining that the urea nozzle has a normally open fault when the second pressure change value is equal to the second preset pressure threshold.

[0047] Specifically, as mentioned earlier, the second preset pressure threshold is the pressure change value in the urea delivery pipe when the nozzle experiences a normally open malfunction. When determining the type of urea system leakage based on the pressure change value in the urea delivery pipe, if the second pressure change value in the urea delivery pipe within a third preset time period equals the second preset pressure threshold, it can be determined that the urea nozzle has experienced a normally open malfunction. Specifically, when the urea nozzle is in the closed state, the urea pump stops operating, and urea in the urea tank stops entering the urea delivery pipe. At this time, if the second pressure change value in the urea delivery pipe within a third preset time period equals the second preset pressure threshold, it indicates that the nozzle should be in the normally open state, and the nozzle has malfunctioned.

[0048] In one embodiment of the present invention, determining the urea system leakage fault type based on the second pressure change value of the urea delivery pipe within a third preset time period further includes: when the second pressure change value is less than a second preset pressure threshold, controlling the urea nozzle to open, and determining the urea system leakage fault type based on the third pressure change value of the urea delivery pipe within a third preset time period, wherein the third pressure change value is the pressure change value corresponding to the urea delivery pipe within the third preset time period when the urea nozzle is in the open state.

[0049] Specifically, when a urea system leak is detected, the urea pump in the urea system is stopped, and the urea nozzle is closed. If the second pressure change value of the urea delivery pipe within a third preset time is less than the second preset pressure threshold, it is assumed that the nozzle is not in the normally open state and the urea tank is not leaking. At this time, the urea nozzle is opened, and the pressure change value of the urea delivery pipe will have a pressure increment based on the second pressure change value. Therefore, the type of urea system leak can be further determined based on the third pressure change value of the urea delivery pipe within a third preset time.

[0050] In one embodiment of the present invention, determining the type of urea system leakage based on a third pressure change value of the urea delivery pipe within a third preset time period includes: determining that the urea delivery pipe has a leakage fault when the third pressure change value is equal to the sum of the second pressure change value and the second preset pressure threshold; and determining that the urea nozzle has a partial jamming fault or the urea delivery pipe has a leakage fault when the third pressure change value is not equal to the sum of the second pressure change value and the second preset pressure threshold.

[0051] Specifically, as mentioned above, the second pressure change value corresponds to the pressure change value of the urea delivery pipe when the urea nozzle is closed. When a leak is detected in the urea delivery pipe, and the second pressure change value of the urea delivery pipe within a third preset time period is less than a second preset pressure threshold, the urea nozzle is opened. Within the third preset time period, the third pressure change value of the urea delivery pipe will have a pressure increment based on the second pressure change value. If this pressure increment is equal to the second preset pressure threshold, that is, the third pressure change value of the urea delivery pipe within the third preset time period is equal to the sum of the second pressure change value and the second preset pressure threshold, then a leak is detected in the urea delivery pipe. Furthermore, if the third pressure change value of the urea delivery pipe within the third preset time period is not equal to the sum of the second pressure change value and the second preset pressure threshold, then a partial jamming fault is detected in the urea nozzle or a minor leak is detected in the urea delivery pipe.

[0052] In a specific embodiment, the third preset time is, for example, 10 seconds, and the second preset pressure threshold is, for example, 2 bar. When the second pressure change value ΔP2 is less than 2 bar, the data control unit (DCU) of the urea system controls the nozzle to open. At this time, it is determined whether the third pressure change value ΔP3 satisfies ΔP3 = ΔP2 + 2 bar. If it satisfies, it means that there is no nozzle jamming problem and there is leakage in the urea delivery pipe. If it does not satisfy, it means that the nozzle is partially jammed and depressurized or there is a slight leakage in the urea delivery pipe.

[0053] In one embodiment of the present invention, after determining the fault type of urea system leakage based on the opening and closing state of the urea nozzle and the pressure change value of the urea delivery pipe, the method further includes: issuing an alarm message.

[0054] Specifically, after determining the type of urea system leakage based on the opening and closing status of the urea nozzle and the pressure change in the urea delivery pipe, an alarm message is issued to allow the user to identify the leaking component and locate the fault. It is understood that the alarm message includes, but is not limited to, text or image prompts displayed on instruments.

[0055] The following is for reference. Figure 3 An example is provided to illustrate the diagnostic method for urea system leakage faults according to an embodiment of the present invention.

[0056] Step S11: When the urea system detects that the difference between the change in urea volume in the urea tank collected by the level sensor and the total urea consumption calculated by the data control unit (DCU) exceeds 1 liter within half an hour, it determines that the urea is abnormally reduced, confirms that the urea system has a leakage fault, and enters the leakage fault diagnosis mode.

[0057] Step S12: Control the nozzle to close, stop the urea pump, and record the first pressure change value △P1.

[0058] Step S13: Determine whether the first pressure change value ΔP1 is greater than the first preset pressure threshold. If yes, proceed to step S14; otherwise, proceed to step S15.

[0059] Step S14: Determine whether the second pressure change value ΔP2 is greater than the second preset pressure threshold. If yes, proceed to step S16; otherwise, proceed to step S17.

[0060] Step S15: If the urea tank is found to be leaking, the instrument will remind the user to check the urea tank.

[0061] Step S16: It is determined that there is a leak in the urea delivery pipe, and the instrument reminds the user to check the urea delivery pipe.

[0062] Step S17: Determine whether the second pressure change value ΔP2 is equal to the second preset pressure threshold. If yes, proceed to step S18; otherwise, proceed to step S19.

[0063] Step S18: It is determined that the urea nozzle has a normally open fault.

[0064] Step S19: Control the nozzle to open and determine whether the third pressure change value △P3 is equal to the sum of the second pressure change value △P2 and the second preset pressure threshold. If yes, proceed to step S16; otherwise, proceed to step S20.

[0065] Step S20: If the problem is determined to be a partial nozzle jamming and pressure relief or a minor leak in the urea delivery pipe, the instrument will issue an alarm.

[0066] According to the diagnostic method for urea system leakage faults according to embodiments of the present invention, when a urea system leakage fault is determined, the type of urea system leakage fault can be identified by controlling the operation of the urea pump, the opening and closing of the nozzle, and judging the pressure changes of the urea delivery pipe of the urea system. This allows the user to be reminded to check in time before the urea leakage in the urea system becomes excessive, thereby avoiding the problem of the vehicle being unable to start due to excessive urea leakage and improving the reliability of the vehicle.

[0067] A further embodiment of the present invention discloses a diagnostic device 100 for urea system leakage faults.

[0068] Figure 4 This is a schematic diagram of the structure of a diagnostic device 100 for urea system leakage faults according to an embodiment of the present invention, as shown below. Figure 4 As shown, the diagnostic device 100 for urea system leakage faults includes: a control module 110, an acquisition module 120, and a determination module 130. The control module 110 is used to control the urea pump of the urea system to stop operating and to control the urea nozzle to close when a leakage fault is determined to have occurred in the urea system; the acquisition module 120 is used to acquire the pressure change value of the urea delivery pipe of the urea system; and the determination module 130 is used to determine the type of urea system leakage fault based on the pressure change value of the urea delivery pipe within a first preset time period.

[0069] In one embodiment of the present invention, the determining module 130 determines that a urea system has a leakage fault, including: acquiring the change in urea volume in the urea tank and the total amount of urea consumed; and determining that a urea system has a leakage fault when the difference between the change in urea volume and the total amount of urea consumed is greater than a preset volume within a second preset time period, wherein the second preset time period is greater than the first preset time period.

[0070] In one embodiment of the present invention, the determining module 130 determines the fault type of urea system leakage based on a first pressure change value of the urea delivery pipe within a first preset time period, including: when the first pressure change value is not greater than a first preset pressure threshold, determining that a urea tank leakage fault has occurred, wherein the first pressure change value is the pressure change value of the urea delivery pipe within the first preset time period when the urea nozzle is in a closed state; when the first pressure change value is greater than the first preset pressure threshold, determining the fault type of urea system leakage based on a second pressure change value of the urea delivery pipe within a third preset time period, wherein the second pressure change value is the pressure change value of the urea delivery pipe within the third preset time period when the urea nozzle is in a closed state, and the third preset time period is less than the first preset time period.

[0071] In one embodiment of the present invention, the determining module 130 determines the type of leakage in the urea system based on the second pressure change value of the urea delivery pipe within a third preset time period, including: determining that the urea delivery pipe has a leakage fault when the second pressure change value is greater than a second preset pressure threshold, wherein the second preset pressure threshold is greater than a first preset pressure threshold.

[0072] In one embodiment of the present invention, the determining module 130 determines the fault type of urea system leakage based on the second pressure change value of the urea delivery pipe within a third preset time period, and further includes: when the second pressure change value is equal to the second preset pressure threshold, determining that the urea nozzle has a normally open fault.

[0073] In one embodiment of the present invention, the determining module 130 determines the fault type of urea system leakage based on the second pressure change value of the urea delivery pipe within a third preset time period, and further includes: when the second pressure change value is less than the second preset pressure threshold, the control module 110 controls the urea nozzle to open, and determines the fault type of urea system leakage based on the third pressure change value of the urea delivery pipe within the third preset time period, wherein the third pressure change value is the pressure change value of the urea delivery pipe corresponding to the urea delivery pipe within the third preset time period when the urea nozzle is in the open state.

[0074] In one embodiment of the present invention, the determining module 130 determines the fault type of urea system leakage based on the third pressure change value of the urea delivery pipe within a third preset time period, including: when the third pressure change value is equal to the sum of the second pressure change value and the second preset pressure threshold, determining that the urea delivery pipe has a leakage fault; when the third pressure change value is not equal to the sum of the second pressure change value and the second preset pressure threshold, determining that the urea nozzle has a partial jamming fault or the urea delivery pipe has a leakage fault.

[0075] It should be noted that the diagnostic device 100 for urea system leakage fault in this embodiment of the invention is implemented in a manner similar to that of the diagnostic method for urea system leakage fault in this embodiment of the invention. For details, please refer to the description in the method section. To reduce redundancy, it will not be repeated here.

[0076] According to the urea system leakage fault diagnosis device 100 of the present invention, when a urea system leakage fault is determined, the type of urea system leakage fault can be identified by controlling the operation of the urea pump, the opening and closing of the nozzle, and judging the pressure change of the urea delivery pipe of the urea system. In this way, the user is reminded to check in time before the urea leakage in the urea system is too large, so as to avoid the problem of the vehicle being unable to start due to excessive urea leakage, thereby improving the reliability of the vehicle.

[0077] Further embodiments of the present invention disclose a vehicle comprising: a urea system; and a diagnostic device for urea system leakage faults as described in any of the above embodiments.

[0078] It should be noted that the specific implementation method for diagnosing urea system leakage faults in the vehicle of the present invention is similar to the specific implementation method for diagnosing urea system leakage faults in the present invention. Please refer to the description in the method section for details. In order to reduce redundancy, it will not be repeated here.

[0079] According to an embodiment of the present invention, when a urea system leak is detected, the type of urea system leak can be identified by controlling the operation of the urea pump, the opening and closing of the nozzle, and judging the pressure changes in the urea delivery pipe of the urea system. This allows the user to be reminded to check in time before the urea leak becomes too large, thus avoiding the problem of the vehicle being unable to start due to excessive urea leakage and improving the reliability of the vehicle.

[0080] A further embodiment of the present invention discloses a computer-readable storage medium storing a diagnostic program for urea system leakage faults. When the diagnostic program for urea system leakage faults is executed by a processor, it implements the diagnostic method for urea system leakage faults as described in any of the above embodiments.

[0081] According to an embodiment of the present invention, when a diagnostic program for urea system leakage fault stored thereon is executed by a processor, when a urea system leakage fault is determined, the type of urea system leakage fault can be identified by controlling the operation of the urea pump, the opening and closing of the nozzle, and judging the pressure changes of the urea delivery pipe of the urea system. This alerts the user to check in time before the urea leakage in the urea system becomes excessive, avoiding vehicle starting problems caused by excessive urea leakage, thereby improving vehicle reliability.

[0082] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "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 the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example.

[0083] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A method for diagnosing leakage faults in a urea system, characterized in that, include: When a leak is detected in the urea system, the urea pump in the urea system is stopped, and the urea nozzle is closed. Obtain the pressure change value of the urea delivery pipe of the urea system; The type of leakage in the urea system is determined based on the first pressure change value of the urea delivery pipe within a first preset time. The method of determining the type of leakage in the urea system based on the first pressure change value of the urea delivery pipe within a first preset time includes: When the first pressure change value is not greater than the first preset pressure threshold, it is determined that the urea tank has a leakage fault, wherein the first pressure change value is the pressure change value of the urea delivery pipe within a first preset time when the urea nozzle is in the closed state. When the first pressure change value is greater than the first preset pressure threshold, the fault type of the urea system leakage is determined according to the second pressure change value of the urea delivery pipe within a third preset time. The second pressure change value is the pressure change value of the urea delivery pipe within a third preset time when the urea nozzle is in the closed state. The third preset time is less than the first preset time. The method of determining the type of leakage in the urea system based on the second pressure change value of the urea delivery pipe within a third preset time period includes: When the second pressure change value is greater than the second preset pressure threshold, it is determined that the urea delivery pipe has a leakage fault, wherein the second preset pressure threshold is greater than the first preset pressure threshold.

2. The diagnostic method for urea system leakage faults according to claim 1, characterized in that, Determining a leak in the urea system includes: The change in urea volume in the urea tank and the total amount of urea consumed are obtained. Within a second preset time period, when the difference between the change in urea volume and the total amount of urea consumed is greater than a preset volume, it is determined that a urea system leakage fault has occurred, wherein the second preset time period is greater than the first preset time period.

3. The diagnostic method for urea system leakage faults according to claim 1, characterized in that, Determining the type of leakage in the urea system based on the second pressure change value of the urea delivery pipe within a third preset time period also includes: When the second pressure change value is equal to the second preset pressure threshold, it is determined that the urea nozzle has a normally open fault.

4. The diagnostic method for urea system leakage faults according to claim 3, characterized in that, Determining the type of leakage in the urea system based on the second pressure change value of the urea delivery pipe within a third preset time period also includes: When the second pressure change value is less than the second preset pressure threshold, the urea nozzle is controlled to open, and the urea system leakage fault type is determined according to the third pressure change value of the urea delivery pipe within the third preset time. The third pressure change value is the pressure change value of the urea delivery pipe within the third preset time when the urea nozzle is in the open state.

5. The diagnostic method for urea system leakage faults according to claim 4, characterized in that, The type of urea system leakage is determined based on the third pressure change value of the urea delivery pipe within the third preset time period, including: When the third pressure change value is equal to the sum of the second pressure change value and the second preset pressure threshold, it is determined that the urea delivery pipe has a leakage fault. When the third pressure change value is not equal to the sum of the second pressure change value and the second preset pressure threshold, it is determined that the urea nozzle has a partial jamming fault or the urea delivery pipe has a leakage fault.

6. A diagnostic device for leakage faults in a urea system, characterized in that, include: The control module is used to control the urea pump of the urea system to stop running and control the urea nozzle to close when a leakage fault is determined to occur in the urea system. The acquisition module is used to acquire the pressure change value of the urea delivery pipe of the urea system; The determination module is used to determine the type of leakage in the urea system based on the pressure change value of the urea delivery pipe within a first preset time period. When determining the urea system leakage fault type based on the first pressure change value of the urea delivery pipe within a first preset time period, the determining module is configured to: determine that a urea tank leakage fault has occurred when the first pressure change value is not greater than a first preset pressure threshold, wherein the first pressure change value is the pressure change value of the urea delivery pipe within the first preset time period when the urea nozzle is in a closed state; and determine the urea system leakage fault type based on the second pressure change value of the urea delivery pipe within a third preset time period when the first pressure change value is greater than the first preset pressure threshold, wherein the second pressure change value is the pressure change value of the urea delivery pipe within the third preset time period when the urea nozzle is in a closed state, and the third preset time period is less than the first preset time period. When determining the type of leakage in the urea system based on the second pressure change value of the urea delivery pipe within a third preset time period, the determining module is configured to: determine that the urea delivery pipe has a leakage fault when the second pressure change value is greater than a second preset pressure threshold, wherein the second preset pressure threshold is greater than the first preset pressure threshold.

7. A vehicle, characterized in that, include: Urea system; as well as, The diagnostic device for urea system leakage faults as described in claim 6.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a diagnostic program for urea system leakage faults, which, when executed by a processor, implements the diagnostic method for urea system leakage faults as described in any one of claims 1-5.

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