Nozzle fault detection method and device, computer device and storage medium

Abstract

The application relates to a nozzle fault detection method and device, computer equipment, a storage medium and a computer program product. The method comprises the following steps: acquiring an initial pressure of a gas rail located in a vehicle; determining a minimum pressure of the gas rail in a spraying cycle during spraying operation of a to-be-detected nozzle of the vehicle; and performing fault detection on the to-be-detected nozzle according to a target pressure difference between the initial pressure and the minimum pressure to obtain a fault detection result of the to-be-detected nozzle. In this way, the accuracy of fault detection of the to-be-detected nozzle is improved.

Description

Technical Field

[0001] This application relates to the field of fault detection technology, and in particular to a nozzle fault detection method, apparatus, computer equipment, storage medium and computer program product. Background Technology

[0002] With the development of vehicle exhaust treatment technology, a technology has emerged that converts nitrogen oxides in exhaust gases into ammonia. After obtaining the ammonia, it needs to be sprayed out through the vehicle's nozzles to achieve the emission of vehicle exhaust gases. If the nozzles malfunction, exhaust emission will fail, therefore, nozzle malfunction detection is necessary.

[0003] In related technologies, the pressure of the air rail inside the vehicle after the nozzle stops spraying is used to detect nozzle malfunctions. However, in low-temperature environments, liquid ammonia is prone to re-vaporization as the rail pressure decreases, leading to an increase in rail pressure. This makes it impossible to accurately determine whether the nozzle has malfunctioned. Summary of the Invention

[0004] Therefore, it is necessary to provide a nozzle fault detection method, apparatus, computer equipment, computer-readable storage medium, and computer program product that can improve the accuracy of nozzle fault detection in response to the above-mentioned technical problems.

[0005] Firstly, this application provides a nozzle failure detection method. The method includes:

[0006] Obtain the initial pressure of the air rail located inside the vehicle;

[0007] During the injection operation of the nozzle under test in the vehicle, the minimum pressure of the air rail during the injection cycle is determined.

[0008] Based on the target pressure difference between the initial pressure and the minimum pressure, the nozzle under test is subjected to fault detection to obtain the fault detection result of the nozzle under test.

[0009] In some embodiments, determining the minimum pressure of the air rail during the injection cycle during the injection operation of the nozzle under test in the vehicle includes: during the injection operation of the nozzle under test in the vehicle, starting from the initial moment of the injection cycle, performing multiple pressure measurements on the air rail at preset intervals to obtain the pressure corresponding to each pressure measurement; and determining the minimum pressure of the air rail during the injection cycle based on each pressure.

[0010] In some embodiments, determining the minimum pressure of the air rail during the injection cycle based on each of the pressures includes: acquiring the comparison pressure corresponding to the previous pressure measurement and the current pressure obtained from the current pressure measurement; determining the target comparison pressure corresponding to the current pressure measurement based on the comparison result of the comparison pressure and the current pressure; if the number of measurements for the current pressure measurement has not reached a preset number of measurements, then using the target comparison pressure as the comparison pressure for the next pressure measurement, performing the next pressure measurement, and returning to the step of obtaining the current pressure from the current pressure measurement to continue execution until the number of measurements for the current pressure measurement reaches the preset number of measurements; and using the target comparison pressure corresponding to the last measurement that reaches the preset number of measurements as the minimum pressure of the air rail during the injection cycle.

[0011] In some embodiments, determining the target comparison pressure corresponding to the current pressure measurement based on the comparison result of the comparison pressure and the current pressure includes: if the comparison result is that the current pressure is less than the comparison pressure, then the current pressure is determined as the target comparison pressure corresponding to the current pressure measurement; if the comparison result is that the current pressure is not less than the comparison pressure, then the comparison pressure is determined as the target comparison pressure corresponding to the current pressure measurement.

[0012] In some embodiments, the step of performing fault detection on the nozzle under test based on the target pressure difference between the initial pressure and the minimum pressure to obtain the fault detection result of the nozzle under test includes: determining the actual ammonia injection volume within the injection cycle based on the target pressure difference between the initial pressure and the minimum pressure; obtaining the theoretical ammonia injection volume of the nozzle under test within the injection cycle; and performing fault detection on the nozzle under test based on the actual ammonia injection volume and the theoretical ammonia injection volume to obtain the fault detection result of the nozzle under test.

[0013] In some embodiments, determining the actual ammonia injection quantity within the injection cycle based on the target pressure difference between the initial pressure and the minimum pressure includes: determining the target pressure difference between the initial pressure and the minimum pressure, and obtaining a target function, wherein the target function is a function of the ammonia injection quantity changing with the pressure difference; and determining the actual ammonia injection quantity within the injection cycle based on the target pressure difference and the target function.

[0014] Secondly, this application also provides a nozzle failure detection device. The device includes:

[0015] The initial pressure acquisition module is used to acquire the initial pressure of the air rail located inside the vehicle.

[0016] The minimum pressure determination module is used to determine the minimum pressure of the air rail during the injection cycle during the injection operation of the nozzle under test of the vehicle.

[0017] The fault detection module is used to perform fault detection on the nozzle under test based on the target pressure difference between the initial pressure and the minimum pressure, and obtain the fault detection result of the nozzle under test.

[0018] Thirdly, this application also provides a computer device. The computer device includes a memory and a processor, the memory storing a computer program, and the processor executing the computer program to perform the following steps:

[0019] Obtain the initial pressure of the air rail located inside the vehicle;

[0020] During the injection operation of the nozzle under test in the vehicle, the minimum pressure of the air rail during the injection cycle is determined.

[0021] Based on the target pressure difference between the initial pressure and the minimum pressure, the nozzle under test is subjected to fault detection to obtain the fault detection result of the nozzle under test.

[0022] Fourthly, this application also provides a computer-readable storage medium. The computer-readable storage medium stores a computer program thereon, which, when executed by a processor, performs the following steps:

[0023] Obtain the initial pressure of the air rail located inside the vehicle;

[0024] During the injection operation of the nozzle under test in the vehicle, the minimum pressure of the air rail during the injection cycle is determined.

[0025] Based on the target pressure difference between the initial pressure and the minimum pressure, the nozzle under test is subjected to fault detection to obtain the fault detection result of the nozzle under test.

[0026] Fifthly, this application also provides a computer program product. The computer program product includes a computer program that, when executed by a processor, performs the following steps:

[0027] Obtain the initial pressure of the air rail located inside the vehicle;

[0028] During the injection operation of the nozzle under test in the vehicle, the minimum pressure of the air rail during the injection cycle is determined.

[0029] Based on the target pressure difference between the initial pressure and the minimum pressure, the nozzle under test is subjected to fault detection to obtain the fault detection result of the nozzle under test.

[0030] The aforementioned nozzle fault detection method, apparatus, computer equipment, storage medium, and computer program product acquire the initial pressure of the air rail located within the vehicle. During the injection operation of the nozzle under test, the minimum pressure of the air rail within the injection cycle is determined. By evaluating the entire injection operation process to determine the minimum pressure, the impact of rail pressure rise caused by the vaporization of cryogenic liquid ammonia on fault detection is effectively reduced. Furthermore, based on the target pressure difference between the initial and minimum pressures, the actual pressure difference change throughout the injection operation process is accurately reflected, enabling precise fault detection of the nozzle under test. This improves the accuracy of nozzle fault detection and reduces the probability of false alarms. Attached Figure Description

[0031] Figure 1 This is an application environment diagram of the nozzle failure detection method in one embodiment;

[0032] Figure 2 This is a flowchart illustrating a nozzle failure detection method in one embodiment;

[0033] Figure 3 This is a flowchart illustrating the steps for determining the fault detection result in one embodiment;

[0034] Figure 4 This is a structural block diagram of a nozzle fault detection device in one embodiment;

[0035] Figure 5 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0037] The nozzle failure detection method provided in this application embodiment can be applied to, for example... Figure 1 In the application environment shown, terminal 102 communicates with server 104 via a network. A data storage system can store the data that server 104 needs to process. The data storage system can be integrated onto server 104, or it can be located in the cloud or on another network server. Terminal 102 and server 104 can execute the nozzle fault detection method independently or collaboratively; the specific implementation is not limited.

[0038] In some embodiments, after receiving a request from terminal 102 to perform fault detection on the nozzle under test of the vehicle, server 104 obtains the initial pressure of the air rail located in the vehicle; during the injection operation of the nozzle under test in the vehicle, server 104 determines the minimum pressure of the air rail during the injection cycle; server 104 performs fault detection on the nozzle under test based on the target pressure difference between the initial pressure and the minimum pressure, and obtains the fault detection result of the nozzle under test.

[0039] The terminal 102 can be, but is not limited to, various personal computers, laptops, smartphones, tablets, IoT devices, and portable wearable devices. IoT devices can include smart speakers, smart TVs, smart air conditioners, and smart in-vehicle systems. Portable wearable devices can include smartwatches, smart bracelets, and head-mounted devices. The server 104 can be implemented using a standalone server or a server cluster consisting of multiple servers.

[0040] In one embodiment, such as Figure 2 As shown, a nozzle fault detection method is provided, which can be applied to computer equipment (the computer equipment can be...) Figure 1 The server 104 in the middle can also be Figure 1 Taking terminal 102 as an example, the following steps are included:

[0041] Step S202: Obtain the initial pressure of the air rail located inside the vehicle.

[0042] The vehicle in question is a means of transportation that emits nitrogen oxides. The vehicle can be a car or a commercial vehicle, such as a heavy-duty diesel truck. After the vehicle generates nitrogen oxides, they can be treated with solid ammonia to produce ammonia gas. The vehicle's gas rail is used to store the generated ammonia gas. For example, ammonia gas heated and released from a tank is injected into the exhaust gas through nozzles via the gas rail.

[0043] Optionally, after receiving a request to perform fault detection on the nozzle to be tested in the vehicle, the computer equipment acquires the initial pressure of the gas rail located inside the vehicle, which is collected by the data acquisition device. This initial pressure is the gas rail pressure when no ammonia is being discharged.

[0044] For example, after receiving a request to perform fault detection on a nozzle to be tested in a vehicle, the computer device acquires the initial pressure of the air rail located in the vehicle collected by the acquisition device, and determines the nozzle to be tested from at least one nozzle in the vehicle according to the nozzle number to be tested carried in the request.

[0045] It should be noted that once the computer device receives the request, it will automatically start fault detection. At this time, the initial pressure of the air rail is first determined and used as a reference pressure to assess the pressure changes of the air rail during the fault detection process.

[0046] Step S204: During the injection operation of the nozzle under test on the vehicle, determine the minimum pressure of the air rail during the injection cycle.

[0047] The vehicle contains at least one nozzle, and one nozzle is selected for fault detection at a time. The injection operation refers to the process of ejecting ammonia gas from the gas rail through the nozzle under test, with the nozzle in the test state and the air rail inlet closed (this can be achieved using a pressure regulating shut-off valve). The time taken for each injection operation is the corresponding injection cycle. The injection cycle is preset, and the minimum pressure refers to the minimum gas rail pressure during the injection operation, reflecting the transient ammonia gas pressure during that operation.

[0048] Optionally, after identifying the nozzle to be tested for nozzle failure detection, the computer equipment performs a spraying operation on the nozzle to be tested. During the spraying operation of ammonia gas into the gas rail through the nozzle to be tested, the computer equipment obtains the minimum pressure within the determined spraying cycle through multiple pressure measurements.

[0049] In some embodiments, determining the minimum pressure of the air rail during the injection cycle during the injection operation of the nozzle under test of the vehicle includes: during the injection operation of the nozzle under test of the vehicle, starting from the initial moment of the injection cycle, taking multiple pressure measurements of the air pressure in the air rail at preset intervals to obtain the pressure corresponding to each pressure measurement; and determining the minimum pressure of the air rail during the injection cycle based on each pressure.

[0050] Optionally, during the injection of ammonia gas into the gas rail through the nozzle under test, the computer equipment starts timing from the initial moment of the injection cycle. Every preset time interval, the data acquisition device measures the pressure of the gas rail at the end of that preset time interval, obtains the corresponding pressure, and sends the measured pressure to the computer equipment. This process continues until the data acquisition device completes a preset number of data acquisitions, at which point it stops measuring pressure and sending pressure data to the computer equipment. Based on the pressure corresponding to each pressure measurement, the computer equipment determines the minimum pressure of the gas rail within the injection cycle.

[0051] For example, if the duration of the injection cycle of the injection operation is the target duration, then the preset number of measurements is determined according to the target duration and the preset duration. For example, if the target duration is 1 second and the preset duration is 1 ms, then 1000 pressure measurements are performed to obtain 1000 pressure readings.

[0052] In this embodiment, during the spraying operation of the nozzle under test in the vehicle, starting from the initial moment of the spraying cycle, the air pressure in the air rail is measured multiple times at preset intervals to obtain the pressure corresponding to each pressure measurement. Based on each pressure, the minimum pressure of the air rail during the spraying cycle can be accurately reflected, which can effectively reduce the impact of the rail pressure rise caused by the vaporization of low-temperature liquid ammonia on fault detection.

[0053] Step S206: Based on the target pressure difference between the initial pressure and the minimum pressure, perform fault detection on the nozzle under test to obtain the fault detection result of the nozzle under test.

[0054] Optionally, the computer device calculates the target pressure difference between the initial pressure and the minimum pressure. If the target pressure difference is not zero, the computer device performs fault detection on the nozzle under test based on the target pressure difference, and obtains the fault detection result of the nozzle under test. If the target pressure difference is zero, the computer device stops performing fault detection on the nozzle under test.

[0055] It should be noted that if the target pressure difference is zero, it indicates that the minimum pressure and the initial pressure are the same. In this case, there may be a complete blockage of the nozzle under test (i.e., the nozzle is not discharging ammonia at all), or there may be an abnormality in the pressure measurement operation. To avoid incorrect fault detection, the computer equipment stops fault detection on the nozzle under test and performs the preset number of pressure measurements again to redetermine the minimum pressure. If the target pressure difference is not zero, it indicates that the measurement operation is normal. Based on this, before performing fault detection, it is necessary to verify the pressure measurement operation based on the target pressure difference value to pre-determine whether fault detection has been performed. If the target pressure difference is not zero, it is determined that multiple measurement operations are normal, and fault detection is performed on the nozzle under test to obtain the fault detection result. If the target pressure difference is zero, fault detection on the nozzle under test is stopped.

[0056] In the aforementioned nozzle fault detection method, the initial pressure of the air rail located within the vehicle is obtained. During the injection operation of the nozzle under test, the minimum pressure of the air rail within the injection cycle is determined. By evaluating the entire injection operation process to determine the minimum pressure, the impact of rail pressure rise caused by the vaporization of cryogenic liquid ammonia on fault detection is effectively reduced. Furthermore, based on the target pressure difference between the initial and minimum pressures, the actual pressure difference change during the entire injection operation is accurately reflected, enabling precise fault detection of the nozzle under test. This results in accurate fault detection results for the nozzle under test, improving the accuracy of fault detection and reducing the probability of false alarms.

[0057] In some embodiments, determining the minimum pressure of the air rail during the injection cycle based on each of the pressures includes: after completing a preset number of measurements, selecting the minimum pressure from the pressures as the minimum pressure.

[0058] It should be noted that the preset number of measurements is the same as the number of pressures, that is, each measurement yields one pressure.

[0059] In this embodiment, by determining the minimum pressure from all measured pressures after completing all pressure measurements, the impact of rail pressure rise caused by cryogenic liquid ammonia vaporization on fault detection can be effectively reduced.

[0060] In some embodiments, determining the minimum pressure of the air rail during the injection cycle based on each pressure includes: acquiring the comparison pressure corresponding to the previous pressure measurement and the current pressure obtained from the current pressure measurement; determining the target comparison pressure corresponding to the current pressure measurement based on the comparison result of the comparison pressure and the current pressure; if the number of measurements for the current pressure measurement has not reached the preset number of measurements, then using the target comparison pressure as the comparison pressure for the next pressure measurement, performing the next pressure measurement, and returning to the step of obtaining the current pressure from the current pressure measurement to continue execution until the number of measurements for the current pressure measurement reaches the preset number of measurements; and using the target comparison pressure corresponding to the last measurement that reaches the preset number of measurements as the minimum pressure of the air rail during the injection cycle.

[0061] Specifically, for the current pressure measurement, the comparison pressure used in the next pressure measurement refers to the comparison pressure corresponding to the current pressure measurement. For example, if the current measurement is the nth pressure measurement, and after obtaining the target comparison pressure Fn corresponding to the nth pressure measurement, if the number of measurements n for the nth pressure measurement has not reached the preset number of measurements, then the target comparison pressure Fn will be used as the comparison pressure corresponding to the nth pressure measurement. The comparison pressure corresponding to the previous pressure measurement refers to the minimum pressure determined after completing the previous pressure measurement, but it is not necessarily the minimum pressure of the air rail during the injection cycle.

[0062] Optionally, if the current pressure measurement is the first pressure measurement, the computer device uses the initial pressure as the comparison pressure corresponding to the previous pressure measurement when performing the first pressure measurement. Based on the initial pressure and the current pressure obtained from the first pressure measurement, the computer device determines the target comparison pressure corresponding to the first pressure measurement and uses the target comparison pressure corresponding to the first pressure measurement as the comparison pressure corresponding to the first pressure measurement.

[0063] If the current pressure measurement is not the first pressure measurement, the computer will obtain the comparison pressure corresponding to the previous pressure measurement and the current pressure obtained from the current pressure measurement. Based on the comparison result of the comparison pressure and the current pressure, the target comparison pressure corresponding to the current pressure measurement will be determined. If the number of measurements for the current pressure measurement has not reached the preset number of measurements, the target comparison pressure will be used as the comparison pressure for the next pressure measurement, and the next pressure measurement will be performed. The process will then return to the step of obtaining the current pressure for the current pressure measurement and continue until the number of measurements for the current pressure measurement reaches the preset number of measurements. The computer will obtain the target comparison pressure corresponding to the last measurement that has reached the preset number of measurements and directly set the target comparison pressure corresponding to the last measurement to the minimum pressure of the air rail during the injection cycle.

[0064] In some embodiments, determining the target comparison pressure corresponding to the current pressure measurement based on the comparison result of the comparison pressure and the current pressure includes: if the comparison result is that the current pressure is less than the comparison pressure, then the current pressure is determined as the target comparison pressure corresponding to the current pressure measurement; if the comparison result is that the current pressure is not less than the comparison pressure, then the comparison pressure is determined as the target comparison pressure corresponding to the current pressure measurement.

[0065] It should be noted that the comparison pressure corresponding to the previous pressure measurement reflects the minimum pressure determined before the current pressure measurement. However, the comparison pressure corresponding to the previous pressure measurement cannot be directly determined as the minimum pressure before the preset number of measurements is reached. This is because the current pressure or the pressure obtained from subsequent pressure measurements may be lower than the comparison pressure corresponding to the previous pressure measurement. Therefore, the minimum pressure can only be determined after the preset number of measurements is reached.

[0066] Optionally, if the comparison pressure is less than or equal to the current pressure, the computer device will use the comparison pressure as the target comparison pressure corresponding to the current pressure measurement; if the comparison pressure is greater than the current pressure, the computer device will use the current pressure as the target comparison pressure corresponding to the current pressure measurement.

[0067] For example, if the current pressure measurement is the nth time, the pressure obtained from the nth pressure measurement (i.e., the air pressure measured in the air rail in the current time) is F1, and the comparison pressure corresponding to the previous pressure vehicle is F2. If F1 < F2, then when performing the (n+1)th measurement, the comparison pressure corresponding to the nth pressure measurement is F1; if F1 ≥ F2, then when performing the (n+1)th measurement, the comparison pressure corresponding to the nth pressure measurement is still F2.

[0068] Based on this, if the comparison result shows that the current pressure is less than the comparison pressure, then the current pressure is determined as the target comparison pressure corresponding to the current pressure measurement; if the comparison result shows that the current pressure is not less than the comparison pressure, then the comparison pressure is determined as the target comparison pressure corresponding to the current pressure measurement. In this way, the minimum pressure corresponding to the current pressure measurement can be continuously updated, enabling timely determination of the corresponding minimum pressure after the current measurement is completed, thus improving the timeliness of minimum pressure determination.

[0069] In this embodiment, by acquiring the comparison pressure corresponding to the previous pressure measurement and the current pressure obtained from the current pressure measurement, and based on the comparison result between the comparison pressure and the current pressure, the minimum pressure corresponding to the current pressure measurement can be updated in a timely manner after the current pressure measurement is completed, thus determining the target comparison pressure corresponding to the current pressure measurement. If the number of measurements for the current pressure measurement has not reached the preset number of measurements, the target comparison pressure is used as the comparison pressure for the next pressure measurement, and the process returns to the step of obtaining the current pressure from the current pressure measurement until the number of measurements for the current pressure measurement reaches the preset number of measurements. The target comparison pressure corresponding to the last measurement that reaches the preset number of measurements is taken as the minimum pressure of the air rail during the injection cycle. In this way, the minimum pressure is determined immediately after the current measurement is completed, which improves the timeliness of minimum pressure determination.

[0070] In some embodiments, fault detection is performed on the nozzle under test based on the target pressure difference between the initial pressure and the minimum pressure to obtain the fault detection result of the nozzle under test, including: determining the actual ammonia injection volume within the injection cycle based on the target pressure difference between the initial pressure and the minimum pressure; obtaining the theoretical ammonia injection volume of the nozzle under test within the injection cycle; and performing fault detection on the nozzle under test based on the actual ammonia injection volume and the theoretical ammonia injection volume to obtain the fault detection result of the nozzle under test.

[0071] Optionally, after determining the target pressure difference between the initial pressure and the minimum pressure, the computer equipment determines the actual ammonia injection rate within the injection cycle based on the target pressure difference. The computer equipment acquires the attribute information of the nozzle under test, determines the theoretical ammonia injection rate of the nozzle under test within the injection cycle based on the attribute information, and determines the fault detection result of the nozzle under test based on the comparison between the actual ammonia injection rate and the theoretical ammonia injection rate.

[0072] Among them, the attribute information of the nozzle under test reflects the emission rate of the nozzle. For example, the amount of ammonia gas injected per second is A. Based on this, the theoretical amount of ammonia gas injected by the nozzle under test during the injection cycle can be determined according to the injection cycle and attribute information.

[0073] For example, after determining the actual ammonia injection rate, the computer equipment determines the theoretical ammonia injection rate of the nozzle under test within the injection cycle based on the product of the nozzle's attribute information and the duration of the injection cycle. The computer equipment compares the actual ammonia injection rate with the theoretical ammonia injection rate within the same injection cycle. If the actual ammonia injection rate equals the theoretical ammonia injection rate, the nozzle under test is determined to be functioning correctly. If the actual ammonia injection rate does not equal the theoretical ammonia injection rate, the nozzle under test is determined to be faulty. Further, if the actual ammonia injection rate is less than the theoretical ammonia injection rate, the fault type of the nozzle under test is determined to be a blockage fault, i.e., incomplete blockage. If the actual ammonia injection rate is not less than the theoretical ammonia injection rate, the fault type of the nozzle under test is determined to be an over-injection fault.

[0074] For example, after determining that the nozzle under test is faulty, the computer equipment calculates the injection difference between the actual ammonia injection rate and the theoretical ammonia injection rate. If the actual ammonia injection rate is less than the theoretical ammonia injection rate, the injection difference is determined to be less than zero, and the fault type of the nozzle under test is determined to be a blockage fault. To determine the severity of the blockage fault, i.e., the degree of blockage, the absolute value of the injection difference is used as the first absolute value, and multiple first blockage degrees are obtained. Each first blockage degree is different, and each first blockage degree corresponds to a first blockage difference range. From the multiple first blockage difference ranges, the first blockage difference range to which the first absolute value belongs is selected. The first blockage degree corresponding to the selected first blockage difference range is determined as the first blockage degree of the nozzle under test. Based on the first blockage degree of the nozzle under test, the corresponding blockage repair operation is performed. The first absolute value is positively correlated with the first blockage degree of the nozzle under test; that is, the larger the first absolute value, the greater the first blockage degree of the nozzle under test.

[0075] If the actual ammonia injection volume is not less than the theoretical ammonia injection volume, then the injection difference is determined to be greater than zero, and the fault type of the nozzle under test is determined to be over-injection fault. In order to determine the severity of the over-injection fault of the nozzle under test, i.e. the degree of over-injection, the absolute value of the injection difference is used as the second absolute value.

[0076] Multiple first overspray levels are obtained, each unique, and each corresponding to a first overspray difference range. From these ranges, the first overspray difference range containing a second absolute value is selected. The first overspray level corresponding to this selected range is determined as the first overspray level of the nozzle under test. Based on this first overspray level, corresponding overspray repair operations are performed. The second absolute value is positively correlated with the first overspray level of the nozzle under test; that is, the larger the second absolute value, the greater the first overspray level of the nozzle under test.

[0077] In this embodiment, the target pressure difference between the initial pressure and the minimum pressure accurately reflects the actual pressure difference change throughout the entire injection operation, thereby precisely determining the actual ammonia injection rate within the injection cycle. The theoretical ammonia injection rate of the nozzle under test within the injection cycle is obtained, and based on the actual and theoretical ammonia injection rates, timely and accurate fault detection is performed on the nozzle under test, yielding the fault detection results. This improves the accuracy of fault detection for the nozzle under test and reduces the probability of false alarms.

[0078] In some instances, fault detection of the nozzle under test involves multiple injection operations. For each injection operation, steps S202 to S204 are executed. After step S204, for each injection operation, the computer determines the actual ammonia injection volume within the injection cycle based on the target pressure difference between the initial pressure and the minimum pressure corresponding to that injection operation. After obtaining the actual ammonia injection volume for each injection operation, the computer superimposes multiple actual ammonia injection volumes to determine the actual total ammonia injection volume. Based on the attribute information of the nozzle under test, the computer determines the theoretical ammonia injection volume of the nozzle under test within a single injection cycle, and superimposes multiple theoretical ammonia injection volumes to obtain the theoretical total ammonia injection volume. After determining the actual total ammonia injection volume and the theoretical total ammonia injection volume, the computer compares the actual total ammonia injection volume with the theoretical total ammonia injection volume. If the actual total ammonia injection volume is equal to the theoretical total ammonia injection volume, it is determined that the nozzle under test is not faulty. If the actual total ammonia injection rate is not equal to the theoretical total ammonia injection rate, the nozzle under test is determined to be faulty. Furthermore, if the actual total ammonia injection rate is less than the theoretical total ammonia injection rate, the fault type of the nozzle under test is determined to be a blockage fault, i.e., incomplete blockage. If the actual total ammonia injection rate is not less than the theoretical total ammonia injection rate, the fault type of the nozzle under test is determined to be an over-injection fault. Each injection operation corresponds to one injection cycle, and the duration of each injection cycle is the same.

[0079] For example, after determining that the nozzle under test is faulty, the computer equipment calculates the total injection difference between the actual total ammonia injection volume and the theoretical total ammonia injection volume. If the actual total ammonia injection volume is less than the theoretical total ammonia injection volume, the total injection difference is determined to be less than zero, and the fault type of the nozzle under test is determined to be a blockage fault. To determine the severity of the blockage fault, i.e., the degree of blockage, the absolute value of the total injection difference is used as the third absolute value to obtain multiple second blockage degrees. Each second blockage degree is different from the others, and each second blockage degree corresponds to a second blockage difference range. From the multiple second blockage difference ranges, the second blockage difference range to which the third absolute value belongs is selected. The second blockage degree corresponding to the selected second blockage difference range is determined as the second blockage degree of the nozzle under test. Based on the second blockage degree of the nozzle under test, the corresponding blockage repair operation is performed. The third absolute value is positively correlated with the second blockage degree of the nozzle under test; that is, the larger the third absolute value, the greater the second blockage degree of the nozzle under test.

[0080] If the actual total ammonia injection volume is not less than the theoretical total ammonia injection volume, then the total injection difference is determined to be greater than zero, and the fault type of the nozzle under test is determined to be over-injection fault. In order to determine the severity of the over-injection fault of the nozzle under test, i.e. the degree of over-injection, the absolute value of the injection difference is used as the fourth absolute value.

[0081] Multiple second overspray levels are obtained, each distinct and corresponding to a specific range of overspray differences. From these ranges, the range corresponding to the fourth absolute value is selected. The second overspray level corresponding to this selected range is defined as the second overspray level of the nozzle under test. Based on this second overspray level, corresponding overspray repair operations are performed. The fourth absolute value is positively correlated with the second overspray level of the nozzle under test; that is, the larger the fourth absolute value, the greater the second overspray level.

[0082] In this example, the actual total ammonia injection volume can be obtained with high validity through multiple injection operations. Based on this, the actual total ammonia injection volume and the theoretical total ammonia injection volume can be compared to more accurately screen whether the nozzle under test is faulty, thus further improving the accuracy of fault detection.

[0083] In some embodiments, determining the actual ammonia injection quantity within an injection cycle based on the target pressure difference between the initial pressure and the minimum pressure includes: determining the target pressure difference between the initial pressure and the minimum pressure, and obtaining an objective function, wherein the objective function is a function of how the ammonia injection quantity changes with the pressure difference; and determining the actual ammonia injection quantity within an injection cycle based on the target pressure difference and the objective function.

[0084] Optionally, after determining the target pressure difference and the objective function, the computer device determines the average temperature of the nozzle under test and the amount of ammonia injected during the injection cycle, and determines the actual ammonia injection amount during the injection cycle based on the average temperature, the target pressure difference, the amount of ammonia injected, and the objective function.

[0085] For example, after obtaining the average temperature T, the target pressure difference P, and the amount of ammonia injected n, the actual ammonia injection rate V during the injection cycle is calculated using the following objective function:

[0086] pV = nRT

[0087] Where R is the molar gas constant (also called the universal gas constant) (J / (mol·K)).

[0088] In this embodiment, the target pressure difference between the initial pressure and the minimum pressure is determined, and the objective function is obtained. The objective function is a function of how the ammonia injection rate changes with the pressure difference. Based on the target pressure difference and the objective function, the actual ammonia injection rate during the injection cycle can be determined quickly and accurately. This eliminates the influence of the liquid-gas transition of ammonia at low temperatures on pressure fluctuations and reduces the probability of false nozzle malfunctions.

[0089] In a specific embodiment, such as Figure 3 The diagram shown is a flowchart illustrating the steps for determining the fault detection result in one embodiment.

[0090] Specifically, for each injection operation, the computer acquires the initial pressure of the air rail within the vehicle during the corresponding injection cycle, the comparison pressure corresponding to the previous pressure measurement, and the current pressure obtained from the current pressure measurement. The computer determines whether the current pressure is less than the comparison pressure corresponding to the previous pressure measurement. If so, the current pressure is used as the target comparison pressure for the current pressure measurement; otherwise, the comparison pressure corresponding to the previous pressure measurement is used as the target comparison pressure for the current pressure measurement. If the number of measurements for the current pressure measurement has not reached the preset number of measurements, the target comparison pressure is used as the comparison pressure for the next pressure measurement, and the next pressure measurement is performed. The process then returns to the step of obtaining the current pressure for the current pressure measurement and continues until the number of measurements for the current pressure measurement reaches the preset number of measurements. The target comparison pressure corresponding to the last measurement that reaches the preset number of measurements is taken as the minimum pressure of the air rail during the injection cycle.

[0091] The computer equipment determines the target pressure difference between the initial pressure and the minimum pressure, and obtains the objective function, which is a function of how the ammonia injection rate changes with the pressure difference. Based on the target pressure difference and the objective function, the actual ammonia injection rate within the injection cycle is determined. Each injection operation corresponds to one injection cycle, and the duration of each injection cycle is the same.

[0092] The computer equipment superimposes the actual ammonia injection volume corresponding to multiple injection operations to determine the actual total ammonia injection volume. Based on the attribute information of the nozzle under test, the computer equipment determines the theoretical ammonia injection volume of the nozzle under test within a single injection cycle, and superimposes multiple theoretical ammonia injection volumes to obtain the theoretical total ammonia injection volume. After determining the actual and theoretical total ammonia injection volumes, the computer equipment compares them. If the actual and theoretical total ammonia injection volumes are equal, the nozzle under test is determined to be without fault. If they are not equal, the nozzle under test is determined to be faulty. Further, if the actual total ammonia injection volume is less than the theoretical total ammonia injection volume, the fault type of the nozzle under test is determined to be a blockage fault, i.e., incomplete blockage. If the actual total ammonia injection volume is not less than the theoretical total ammonia injection volume, the fault type of the nozzle under test is determined to be an over-injection fault.

[0093] If the actual total ammonia injection rate is less than the theoretical total ammonia injection rate, the total injection difference is determined to be less than zero, and the fault type of the nozzle under test is determined to be a blockage fault. To determine the severity of the blockage fault, i.e., the degree of blockage, the absolute value of the total injection difference is used as the third absolute value to obtain multiple second blockage degrees. Each second blockage degree is different and corresponds to a second blockage difference range. From these multiple second blockage difference ranges, the second blockage difference range to which the third absolute value belongs is selected. The second blockage degree corresponding to the selected second blockage difference range is determined as the second blockage degree of the nozzle under test. Based on the second blockage degree of the nozzle under test, corresponding blockage repair operations are performed. The third absolute value is positively correlated with the second blockage degree of the nozzle under test; that is, the larger the third absolute value, the greater the second blockage degree of the nozzle under test.

[0094] If the actual total ammonia injection rate is not less than the theoretical total ammonia injection rate, then the total injection difference is determined to be greater than zero, and the fault type of the nozzle under test is determined to be an over-injection fault. To determine the severity of the over-injection fault of the nozzle under test, i.e., the degree of over-injection, the absolute value of the injection difference is used as the fourth absolute value. Multiple second over-injection degrees are obtained, each of which is different and corresponds to a second over-injection difference range. From these multiple second over-injection difference ranges, the second over-injection difference range to which the fourth absolute value belongs is selected. The second over-injection degree corresponding to the selected second over-injection difference range is determined as the second over-injection degree of the nozzle under test. Based on the second over-injection degree of the nozzle under test, corresponding over-injection repair operations are performed. The fourth absolute value is positively correlated with the second over-injection degree of the nozzle under test; that is, the larger the fourth absolute value, the greater the second over-injection degree of the nozzle under test.

[0095] In this embodiment, the initial pressure of the gas rail located within the vehicle is acquired. During the injection operation of the nozzle under test, the minimum pressure of the gas rail within the injection cycle is determined. By evaluating the entire injection operation process and determining the minimum pressure, the impact of rail pressure rise caused by the vaporization of cryogenic liquid ammonia on fault detection is effectively reduced. Furthermore, based on the target pressure difference between the initial and minimum pressures, the actual pressure difference change during the entire injection operation is accurately reflected, enabling precise fault detection of the nozzle under test. This improves the accuracy of nozzle fault detection and reduces the probability of false alarms. In addition, multiple injection operations yield a highly effective actual total ammonia injection volume. Based on this, the actual and theoretical total ammonia injection volumes can be compared to more accurately screen for faults in the nozzle under test, further improving fault detection accuracy. Moreover, multiple pressure measurements and sampling are performed during each injection operation, improving the accuracy of nozzle blockage fault detection without increasing the system's sampling load.

[0096] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0097] Based on the same inventive concept, this application also provides a nozzle fault detection device for implementing the nozzle fault detection method described above. The solution provided by this device is similar to the solution described in the above method; therefore, the specific limitations in one or more nozzle fault detection device embodiments provided below can be found in the limitations of the nozzle fault detection method described above, and will not be repeated here.

[0098] In one embodiment, such as Figure 4 As shown, a nozzle fault detection device 400 is provided, including: an initial pressure acquisition module 402, a minimum pressure determination module 404, and a fault detection module 406, wherein:

[0099] The initial pressure acquisition module 402 is used to acquire the initial pressure of the air rail located inside the vehicle;

[0100] Minimum pressure determination module 404 is used to determine the minimum pressure of the air rail during the injection cycle of the nozzle under test in the vehicle.

[0101] The fault detection module 406 is used to perform fault detection on the nozzle under test based on the target pressure difference between the initial pressure and the minimum pressure, and obtain the fault detection result of the nozzle under test.

[0102] In some embodiments, the minimum pressure determination module 404 is used to perform multiple pressure measurements on the air rail at preset intervals during the injection operation of the nozzle under test of the vehicle, starting from the initial moment of the injection cycle, to obtain the pressure corresponding to each pressure measurement; and to determine the minimum pressure of the air rail during the injection cycle based on each pressure.

[0103] In some embodiments, the minimum pressure determination module 404 is used to obtain the comparison pressure corresponding to the previous pressure measurement and the current pressure obtained from the current pressure measurement; determine the target comparison pressure corresponding to the current pressure measurement based on the comparison result of the comparison pressure and the current pressure; if the number of measurements for the current pressure measurement has not reached the preset number of measurements, then the target comparison pressure is used as the comparison pressure for the next pressure measurement, the next pressure measurement is performed, and the current pressure measurement is returned to the current pressure measurement to continue execution until the number of measurements for the current pressure measurement reaches the preset number of measurements; the target comparison pressure corresponding to the last measurement that reaches the preset number of measurements is used as the minimum pressure of the air rail during the injection cycle.

[0104] In some embodiments, the minimum pressure determination module 404 is used to determine the current pressure as the target comparison pressure corresponding to the current pressure measurement if the comparison result is that the current pressure is less than the comparison pressure; and to determine the comparison pressure as the target comparison pressure corresponding to the current pressure measurement if the comparison result is that the current pressure is not less than the comparison pressure.

[0105] In some embodiments, the fault detection module 406 is used to determine the actual ammonia injection amount within the injection cycle based on the target pressure difference between the initial pressure and the minimum pressure; obtain the theoretical ammonia injection amount of the nozzle under test within the injection cycle; and perform fault detection on the nozzle under test based on the actual ammonia injection amount and the theoretical ammonia injection amount to obtain the fault detection result of the nozzle under test.

[0106] In some embodiments, the fault detection module 406 is used to determine the target pressure difference between the initial pressure and the minimum pressure, and to obtain the objective function, which is a function of the ammonia injection quantity changing with the pressure difference; based on the target pressure difference and the objective function, to determine the actual ammonia injection quantity within the injection cycle.

[0107] Each module in the aforementioned nozzle fault detection device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device, or stored in the memory of a computer device as software, so that the processor can call and execute the corresponding operations of each module.

[0108] In one embodiment, a computer device is provided, which may be a server, and its internal structure diagram may be as follows: Figure 5 As shown, this computer device includes a processor, memory, input / output (I / O) interfaces, and a communication interface. The processor, memory, and I / O interfaces are connected via a system bus, and the communication interface is also connected to the system bus via the I / O interfaces. The processor provides computational and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and a database. The internal memory provides the environment for the operating system and computer programs stored in the non-volatile storage media to run. The I / O interfaces are used for exchanging information between the processor and external devices. The communication interface is used for communicating with external terminals via a network connection. When the computer program is executed by the processor, it implements a nozzle fault detection method.

[0109] Those skilled in the art will understand that Figure 5 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0110] In one embodiment, a computer device is provided, including a memory and a processor. The memory stores a computer program, and the processor executes the computer program to perform the following steps: acquiring the initial pressure of an air rail located inside a vehicle; determining the minimum pressure of the air rail during the injection cycle of a nozzle under test in the vehicle; and performing fault detection on the nozzle under test based on the target pressure difference between the initial pressure and the minimum pressure to obtain a fault detection result for the nozzle under test.

[0111] In one embodiment, when the processor executes the computer program, it further performs the following steps: during the injection operation of the nozzle under test in the vehicle, starting from the initial moment of the injection cycle, the air pressure in the air rail is measured multiple times at preset intervals to obtain the pressure corresponding to each pressure measurement; based on each pressure, the minimum pressure of the air rail during the injection cycle is determined.

[0112] In one embodiment, when the processor executes the computer program, it further implements the following steps: obtaining the comparison pressure corresponding to the previous pressure measurement and the current pressure obtained from the current pressure measurement; determining the target comparison pressure corresponding to the current pressure measurement based on the comparison result of the comparison pressure and the current pressure; if the number of measurements for the current pressure measurement has not reached the preset number of measurements, then using the target comparison pressure as the comparison pressure for the next pressure measurement, performing the next pressure measurement, and returning to the step of obtaining the current pressure from the current pressure measurement to continue execution until the number of measurements for the current pressure measurement reaches the preset number of measurements; and using the target comparison pressure corresponding to the last measurement that reaches the preset number of measurements as the minimum pressure of the air rail during the injection cycle.

[0113] In one embodiment, when the processor executes the computer program, it further implements the following steps: if the comparison result is that the current pressure is less than the comparison pressure, then the current pressure is determined as the target comparison pressure corresponding to the current pressure measurement; if the comparison result is that the current pressure is not less than the comparison pressure, then the comparison pressure is determined as the target comparison pressure corresponding to the current pressure measurement.

[0114] In one embodiment, when the processor executes the computer program, it further performs the following steps: determining the actual ammonia injection quantity within the injection cycle based on the target pressure difference between the initial pressure and the minimum pressure; obtaining the theoretical ammonia injection quantity of the nozzle under test within the injection cycle; and performing fault detection on the nozzle under test based on the actual ammonia injection quantity and the theoretical ammonia injection quantity to obtain the fault detection result of the nozzle under test.

[0115] In one embodiment, when the processor executes the computer program, it further performs the following steps: determining a target pressure difference between the initial pressure and the minimum pressure, and obtaining a target function, which is a function of how the ammonia injection rate changes with the pressure difference; and determining the actual ammonia injection rate within the injection cycle based on the target pressure difference and the target function.

[0116] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, performs the following steps: acquiring the initial pressure of an air rail located within a vehicle; determining the minimum pressure of the air rail during an injection cycle while the nozzle under test in the vehicle is performing an injection operation; and performing fault detection on the nozzle under test based on the target pressure difference between the initial pressure and the minimum pressure, thereby obtaining a fault detection result for the nozzle under test.

[0117] In one embodiment, when the computer program is executed by the processor, it further performs the following steps: during the injection operation of the nozzle under test in the vehicle, starting from the initial moment of the injection cycle, the air pressure in the air rail is measured multiple times at preset intervals to obtain the pressure corresponding to each pressure measurement; based on each pressure, the minimum pressure of the air rail during the injection cycle is determined.

[0118] In one embodiment, when the computer program is executed by the processor, it further implements the following steps: obtaining the comparison pressure corresponding to the previous pressure measurement and the current pressure obtained from the current pressure measurement; determining the target comparison pressure corresponding to the current pressure measurement based on the comparison result of the comparison pressure and the current pressure; if the number of measurements for the current pressure measurement has not reached the preset number of measurements, then using the target comparison pressure as the comparison pressure for the next pressure measurement, performing the next pressure measurement, and returning to the step of obtaining the current pressure from the current pressure measurement to continue execution until the number of measurements for the current pressure measurement reaches the preset number of measurements; and using the target comparison pressure corresponding to the last measurement that reaches the preset number of measurements as the minimum pressure of the air rail during the injection cycle.

[0119] In one embodiment, when the computer program is executed by the processor, it further implements the following steps: if the comparison result is that the current pressure is less than the comparison pressure, then the current pressure is determined as the target comparison pressure corresponding to the current pressure measurement; if the comparison result is that the current pressure is not less than the comparison pressure, then the comparison pressure is determined as the target comparison pressure corresponding to the current pressure measurement.

[0120] In one embodiment, when the computer program is executed by the processor, it further performs the following steps: determining the actual ammonia injection quantity within the injection cycle based on the target pressure difference between the initial pressure and the minimum pressure; obtaining the theoretical ammonia injection quantity of the nozzle under test within the injection cycle; and performing fault detection on the nozzle under test based on the actual ammonia injection quantity and the theoretical ammonia injection quantity to obtain the fault detection result of the nozzle under test.

[0121] In one embodiment, when the computer program is executed by the processor, it further performs the following steps: determining a target pressure difference between the initial pressure and the minimum pressure, and obtaining a target function, which is a function of how the ammonia injection rate changes with the pressure difference; and determining the actual ammonia injection rate within the injection cycle based on the target pressure difference and the target function.

[0122] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, performs the following steps: acquiring the initial pressure of an air rail located within a vehicle; determining the minimum pressure of the air rail during an injection cycle while a nozzle under test is performing an injection operation in the vehicle; and performing fault detection on the nozzle under test based on a target pressure difference between the initial pressure and the minimum pressure, thereby obtaining a fault detection result for the nozzle under test.

[0123] In one embodiment, when the computer program is executed by the processor, it further performs the following steps: during the injection operation of the nozzle under test in the vehicle, starting from the initial moment of the injection cycle, the air pressure in the air rail is measured multiple times at preset intervals to obtain the pressure corresponding to each pressure measurement; based on each pressure, the minimum pressure of the air rail during the injection cycle is determined.

[0124] In one embodiment, when the computer program is executed by the processor, it further implements the following steps: obtaining the comparison pressure corresponding to the previous pressure measurement and the current pressure obtained from the current pressure measurement; determining the target comparison pressure corresponding to the current pressure measurement based on the comparison result of the comparison pressure and the current pressure; if the number of measurements for the current pressure measurement has not reached the preset number of measurements, then using the target comparison pressure as the comparison pressure for the next pressure measurement, performing the next pressure measurement, and returning to the step of obtaining the current pressure from the current pressure measurement to continue execution until the number of measurements for the current pressure measurement reaches the preset number of measurements; and using the target comparison pressure corresponding to the last measurement that reaches the preset number of measurements as the minimum pressure of the air rail during the injection cycle.

[0125] In one embodiment, when the computer program is executed by the processor, it further implements the following steps: if the comparison result is that the current pressure is less than the comparison pressure, then the current pressure is determined as the target comparison pressure corresponding to the current pressure measurement; if the comparison result is that the current pressure is not less than the comparison pressure, then the comparison pressure is determined as the target comparison pressure corresponding to the current pressure measurement.

[0126] In one embodiment, when the computer program is executed by the processor, it further performs the following steps: determining the actual ammonia injection quantity within the injection cycle based on the target pressure difference between the initial pressure and the minimum pressure; obtaining the theoretical ammonia injection quantity of the nozzle under test within the injection cycle; and performing fault detection on the nozzle under test based on the actual ammonia injection quantity and the theoretical ammonia injection quantity to obtain the fault detection result of the nozzle under test.

[0127] In one embodiment, when the computer program is executed by the processor, it further performs the following steps: determining a target pressure difference between the initial pressure and the minimum pressure, and obtaining a target function, which is a function of how the ammonia injection rate changes with the pressure difference; and determining the actual ammonia injection rate within the injection cycle based on the target pressure difference and the target function.

[0128] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of the relevant data shall comply with the relevant laws, regulations and standards of the relevant countries and regions.

[0129] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0130] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0131] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A nozzle fault detection method, characterized in that, The method includes: The initial pressure of the gas rail located inside the vehicle is obtained, which is the gas rail pressure when no ammonia is discharged. During the injection operation of the nozzle under test in the vehicle, the minimum pressure of the air rail during the injection cycle is determined, and the minimum pressure is used to reflect the transient ammonia pressure of the injection operation. Calculate the target pressure difference between the initial pressure and the minimum pressure. If the target pressure difference is not zero, determine that multiple pressure measurement operations are normal, and obtain the target function, which is a function of the ammonia injection rate changing with the pressure difference. The actual ammonia injection rate during the injection cycle is determined based on the target pressure difference and the target function. The theoretical ammonia injection rate of the nozzle under test during the injection cycle is obtained, and the nozzle under test is subjected to fault detection based on the actual ammonia injection rate and the theoretical ammonia injection rate to obtain the fault detection result of the nozzle under test.

2. The method according to claim 1, characterized in that, During the injection operation of the nozzle under test on the vehicle, determining the minimum pressure of the air rail during the injection cycle includes: During the spraying operation of the nozzle under test in the vehicle, starting from the initial moment of the spraying cycle, the air pressure in the air rail is measured multiple times at preset intervals to obtain the pressure corresponding to each pressure measurement. Based on the pressures described, the minimum pressure of the air rail during the injection cycle is determined.

3. The method according to claim 2, characterized in that, Determining the minimum pressure of the air rail during the injection cycle based on each of the aforementioned pressures includes: Obtain the comparison pressure corresponding to the previous pressure measurement, and obtain the current pressure from the current pressure measurement; Based on the comparison result between the comparison pressure and the current pressure, the target comparison pressure corresponding to the current pressure measurement is determined; If the number of measurements for the current pressure measurement does not reach the preset number of measurements, the target comparison pressure is used as the comparison pressure for the next pressure measurement, and the next pressure measurement is performed. The process then returns to the step of obtaining the current pressure for the current measurement and continues until the number of measurements for the current pressure measurement reaches the preset number of measurements. The target comparison pressure corresponding to the last measurement number that reaches the preset number of measurements is taken as the minimum pressure of the air rail during the injection cycle.

4. The method according to claim 3, characterized in that, Determining the target comparison pressure corresponding to the current pressure measurement based on the comparison result of the comparison pressure and the current pressure includes: If the comparison result is that the pressure in this measurement is less than the comparison pressure, then the pressure in this measurement is determined as the target comparison pressure corresponding to the pressure measurement in this measurement; If the comparison result is that the pressure at the time is not less than the comparison pressure, then the comparison pressure is determined as the target comparison pressure corresponding to the pressure measurement at the time.

5. A nozzle fault detection device, characterized in that, The device includes: An initial pressure acquisition module is used to acquire the initial pressure of the air rail located inside the vehicle. The initial pressure is the air rail pressure when no ammonia is discharged. The minimum pressure determination module is used to determine the minimum pressure of the air rail during the injection cycle during the injection operation of the nozzle under test of the vehicle. The minimum pressure is used to reflect the transient ammonia pressure of the injection operation. The fault detection module is used to calculate the target pressure difference between the initial pressure and the minimum pressure. If the target pressure difference is not zero, it determines that multiple pressure measurement operations are normal and obtains a target function, which is a function of the ammonia injection rate changing with the pressure difference. Based on the target pressure difference and the target function, it determines the actual ammonia injection rate within the injection cycle. It obtains the theoretical ammonia injection rate of the nozzle under test within the injection cycle and performs fault detection on the nozzle under test based on the actual ammonia injection rate and the theoretical ammonia injection rate to obtain the fault detection result of the nozzle under test.

6. The apparatus according to claim 5, characterized in that, The minimum pressure determination module is used to measure the air pressure in the air rail multiple times at preset intervals during the spraying operation of the nozzle under test in the vehicle, starting from the initial moment of the spraying cycle, to obtain the pressure corresponding to each pressure measurement; and to determine the minimum pressure of the air rail in the spraying cycle based on each pressure.

7. The apparatus according to claim 5, characterized in that, The minimum pressure determination module is used to obtain the comparison pressure corresponding to the previous pressure measurement and the current pressure obtained from the current pressure measurement; based on the comparison result of the comparison pressure and the current pressure, the target comparison pressure corresponding to the current pressure measurement is determined; if the number of measurements for the current pressure measurement has not reached the preset number of measurements, the target comparison pressure is used as the comparison pressure for the next pressure measurement, the next pressure measurement is performed, and the process returns to the step of obtaining the current pressure for the current pressure measurement to continue execution until the number of measurements for the current pressure measurement reaches the preset number of measurements; the target comparison pressure corresponding to the last measurement that reaches the preset number of measurements is used as the minimum pressure of the air rail during the injection cycle.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 4.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 4.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 4.

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