A urea concentration abnormality monitoring method and device, electronic equipment and storage medium

Abstract

The application relates to the field of vehicle post-processing technology and discloses a urea concentration abnormality monitoring method and device, an electronic device and a storage medium, the method comprising the following steps: in response to a monitoring instruction, determining whether the urea concentration at any collection time is valid according to the comparison result of the sound velocity signal at the collection time and the sound velocity signal at the previous collection time; the urea concentration is the collection concentration of urea solution in a urea tank; determining whether a sliding window is valid based on the number of valid urea concentrations in the sliding window, and determining all urea concentrations in the valid sliding window as reference concentrations; the sliding window comprises N continuous collection times; and determining whether the urea solution is abnormal in concentration based on a target concentration corresponding to the reference concentration. In the embodiment, the target concentration corresponding to the urea concentration in the valid sliding window is used to accurately determine whether the urea solution is abnormal in concentration, so that the situation that the urea solution is misjudged or wrongly judged to be abnormal in concentration due to bubbles in the solution is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicle aftertreatment, and in particular to a urea concentration abnormality monitoring method and device, an electronic device, and a storage medium. BACKGROUND

[0002] With the development of science and technology, vehicles are becoming more and more popular. Nitrogen oxides (NOx) in vehicle exhaust emissions can cause environmental pollution. In order to reduce the emission of nitrogen oxides, urea is sprayed through a urea injection system, and the urea reacts with nitrogen oxides to decompose. The urea concentration affects the decomposition effect, so it is necessary to monitor the urea concentration in a timely manner.

[0003] In related technologies, an ultrasonic technology is used to collect the urea solution concentration through a urea concentration sensor, and abnormality monitoring is directly performed based on the urea solution concentration.

[0004] However, there are often air bubbles in the urea solution, and when the air bubbles adhere to the surface of the probe of the urea concentration sensor, they will affect the monitoring result, so the above-mentioned method is difficult to accurately monitor the concentration abnormality. SUMMARY

[0005] The present application provides a urea concentration abnormality monitoring method, device, electronic device, and storage medium to accurately monitor the concentration abnormality of the urea solution.

[0006] In a first aspect, the present application provides a urea concentration abnormality monitoring method, which comprises:

[0007] In response to a monitoring instruction, determining whether the urea concentration at any collection time is valid according to the comparison result of the sound velocity signal at the collection time and the sound velocity signal at the previous collection time; wherein the urea concentration is the collection concentration of the urea solution in the urea tank;

[0008] Determining whether the sliding window is valid based on the number of valid urea concentrations in the sliding window, and determining all urea concentrations in the valid sliding window as reference concentrations; wherein the sliding window contains N consecutive collection times;

[0009] Determining whether the urea solution is concentration abnormal based on the target concentration corresponding to the reference concentration.

[0010] The above scheme, since the sound speed signal is obtained based on the transmission time and the receiving time, therefore, when there are bubbles and no bubbles in the urea solution, the sound speed signal will be different; by comparing the sound speed signals of the two adjacent collection time points, it can be determined whether the corresponding urea concentration is valid; further, based on the urea concentrations of the continuous multiple collection time points in the sliding window, it is determined whether the overall concentration in the sliding window is valid, and the urea concentration in the valid sliding window is less affected by the bubbles; therefore, all the urea concentrations in the valid sliding window are determined as the reference concentration, and then based on the target concentration corresponding to the reference concentration, the urea solution can be accurately determined whether the concentration is abnormal, and the misjudgment and wrong judgment of the concentration abnormality due to the bubbles in the solution can be reduced.

[0011] In some optional embodiments, according to the comparison result of the sound speed signal of any collection time point and the sound speed signal of the last collection time point, whether the urea concentration of the collection time point is valid, comprising:

[0012] determining the sound speed difference between the sound speed signal of the collection time point and the sound speed signal of the last collection time point;

[0013] if the sound speed difference is less than a preset difference, it is determined that the urea concentration of the collection time point is valid; otherwise, it is determined that the urea concentration of the collection time point is invalid.

[0014] The above scheme, if the difference between the sound speed signals is greater, the probability of bubbles existing in the urea solution is also greater, by determining the sound speed difference between the sound speed signal of any collection time point and the sound speed signal of the last collection time point, and then comparing the sound speed difference with the preset difference; if the sound speed difference is less than the preset difference, it means that the difference between the sound speed signal of the collection time point and the sound speed signal of the last collection time point is small, and the probability of bubbles existing in the urea solution is low, and it is determined that the urea concentration of the collection time point is valid; on the contrary, if the sound speed difference is greater than or equal to the preset difference, it means that the difference between the sound speed signal of the collection time point and the sound speed signal of the last collection time point is large, and the probability of bubbles existing in the urea solution is large, and it is determined that the urea concentration of the collection time point is invalid, thereby accurately determining the validity of each urea concentration.

[0015] In some optional embodiments, based on the number of valid urea concentrations in the sliding window, whether the sliding window is valid, comprising:

[0016] if the number of valid urea concentrations in the sliding window is greater than or equal to a preset number, it is determined that the sliding window is valid; otherwise, it is determined that the sliding window is invalid.

[0017] The above scheme, if the number of valid urea concentrations in the sliding window is greater than or equal to the preset number, it indicates that the fluctuation of the sound speed signal in this period of time is not large, and the overall is relatively stable, it is determined that the sliding window is valid, and the urea concentration in the sliding window can be used as the basis for subsequent abnormal judgment; on the contrary, if the number of valid urea concentrations in the sliding window is less than the preset number, it indicates that the fluctuation of the sound speed signal in this period of time is large, and the overall is not stable enough, and it is likely to be affected by bubbles, therefore, it is determined that the sliding window is invalid, and the urea concentration in the sliding window is not used as the basis for subsequent abnormal judgment, thereby reducing the false alarm probability.

[0018] In some optional embodiments, the target concentration corresponding to the reference concentration is determined by:

[0019] According to the reverse order of the collection time corresponding to the reference concentration, M reference concentrations are selected from all reference concentrations;

[0020] The M reference concentrations are filtered and calculated to obtain the target concentration corresponding to the reference concentration.

[0021] The above scheme selects the M reference concentrations collected at the latest from all reference concentrations, and then filters and calculates the M reference concentrations to efficiently obtain the target concentration representing the current urea state, thereby reducing the interference of historical states and reducing the calculation amount.

[0022] In some optional embodiments, based on the target concentration corresponding to the reference concentration, it is determined whether the urea solution is abnormal in concentration, comprising:

[0023] If the target concentration is greater than or equal to a preset concentration, it is determined that the urea solution is normal in concentration;

[0024] Otherwise, after the urea injection system injects the urea solution based on the calibrated injection amount for a first preset time length, it is determined whether the urea solution is abnormal in concentration based on the concentration of nitrogen oxides in the first preset time length.

[0025] The above scheme, since the target concentration represents the current urea solution state, and the preset concentration represents the lower limit of the allowable urea concentration, by comparing the target concentration with the preset concentration, if the target concentration is greater than or equal to the preset concentration, it indicates that the current urea solution concentration is normal; if the target concentration is less than the preset concentration, it indicates that the solution concentration collected by the urea concentration sensor is low, and it is not directly determined that the urea solution concentration is abnormal, but further judgment is made in combination with the emission effect, thereby further improving the accuracy of abnormal monitoring and reducing the occurrence of false concentration abnormality.

[0026] In some optional embodiments, determining whether the urea solution is abnormal in concentration based on the concentration of the nitrogen oxide within the first preset time period comprises:

[0027] If the concentration of the nitrogen oxide is in an upward trend within the first preset time period, it is determined that the urea solution is abnormal in concentration; otherwise, it is determined that the urea solution is normal in concentration.

[0028] In the above scheme, if the target concentration is less than the preset concentration, it indicates that the solution concentration collected by the urea concentration sensor is low, and the urea solution is not directly determined to be abnormal in concentration, but further determination is made in combination with the emission effect; if it is determined that the concentration of the nitrogen oxide is in an upward trend within the first preset time period, it indicates that the decomposition effect is poor, and it is determined that the urea solution is abnormal in concentration, thereby accurately monitoring the abnormality in concentration.

[0029] In some optional embodiments, the urea concentration is collected by a urea concentration sensor; if the concentration of the nitrogen oxide is not in an upward trend within the first preset time period, the method further comprises:

[0030] After a second preset time period, a new target concentration is determined again, and if the new target concentration is less than the preset concentration, it is determined that the urea concentration sensor has a detection fault.

[0031] In the above scheme, if the target concentration is less than the preset concentration (indicating that the concentration is low), and the concentration of the nitrogen oxide is not in an upward trend within the first preset time period (indicating that the concentration is normal), it indicates that the solution concentration collected by the urea concentration sensor may have some errors, which may be caused by bubbles or may be caused by a fault of the urea concentration sensor itself; since the bubbles in the urea solution do not exist all the time, a new target concentration is determined again after a second preset time period, and if the new target concentration is still less than the preset concentration, it is determined that the urea concentration sensor has a detection fault.

[0032] In some optional embodiments, after determining whether the urea solution is abnormal in concentration, the method further comprises:

[0033] If the urea solution is normal in concentration, whether the urea solution is abnormal in concentration is determined again after the urea liquid level signal of the urea tank rises; or

[0034] If the urea solution is abnormal in concentration, information representing the abnormality in urea concentration is notified through a preset notification mode, and a real-time target concentration is monitored; if the real-time target concentration is greater than or equal to the preset concentration within a third preset time period, it is determined that the urea solution is recovered from the abnormality in concentration.

[0035] The above scheme, if the urea solution concentration is normal, and no new urea solution is added in the urea tank, the concentration of the urea solution will not change significantly, so the real-time target concentration is no longer monitored, and the influence of bubbles generated by vehicle shaking on the collection of urea concentration is avoided; only after the urea liquid level signal of the urea tank rises, it is determined whether the concentration of the urea solution is abnormal, which reduces the influence of bubbles and can timely monitor whether inferior urea solution is added. If the concentration of the urea solution is abnormal, information characterizing the abnormal concentration of the urea solution is notified (a fault is reported) so that relevant personnel can process the urea solution in the urea tank, and the real-time target concentration is monitored to know whether the abnormal concentration of the urea solution is restored; if the real-time target concentration is greater than or equal to the preset concentration within a third preset time length, that is, the duration of the target concentration greater than the preset concentration has reached the third preset time length, it is indicated that the abnormal concentration of the urea solution has been restored.

[0036] In a second aspect, the embodiments of the present application provide a urea concentration abnormality monitoring device, comprising:

[0037] an effectiveness determination module configured to, in response to a monitoring instruction, determine whether the urea concentration at any collection time is effective according to a comparison result of the sound velocity signal at the collection time and the sound velocity signal at the previous collection time; wherein the urea concentration is a collected concentration of the urea solution in the urea tank;

[0038] The effectiveness determination module is further configured to determine whether the sliding window is effective based on the number of effective urea concentrations in the sliding window, and determine all urea concentrations in the effective sliding window as reference concentrations; wherein the sliding window comprises consecutive N collection times.

[0039] an abnormality monitoring module configured to determine whether the urea solution is abnormal in concentration based on a target concentration corresponding to the reference concentration.

[0040] In some optional embodiments, the effectiveness determination module is specifically configured to:

[0041] determine a sound velocity difference between the sound velocity signal at the collection time and the sound velocity signal at the previous collection time;

[0042] if the sound velocity difference is less than a preset difference value, it is determined that the urea concentration at the collection time is effective; otherwise, it is determined that the urea concentration at the collection time is ineffective.

[0043] In some optional embodiments, the effectiveness determination module is specifically configured to:

[0044] if the number of effective urea concentrations in the sliding window is greater than or equal to a preset number, it is determined that the sliding window is effective; otherwise, it is determined that the sliding window is ineffective.

[0045] In some optional embodiments, the target concentration corresponding to the reference concentration is determined by the following manner:

[0046] M reference concentrations are selected from all the reference concentrations in a reverse order of the collection time corresponding to the reference concentration;

[0047] The M reference concentrations are filtered to obtain the target concentration corresponding to the reference concentration.

[0048] In some optional embodiments, the abnormality monitoring module is specifically configured to:

[0049] If the target concentration is greater than or equal to a preset concentration, it is determined that the urea solution concentration is normal.

[0050] Otherwise, after the urea injection system injects the urea solution based on a calibrated injection amount for a first preset time length, it is determined whether the urea solution concentration is abnormal based on the concentration of nitrogen oxides within the first preset time length.

[0051] In some optional embodiments, the abnormality monitoring module is specifically configured to:

[0052] If the concentration of nitrogen oxides is in an upward trend within the first preset time length, it is determined that the urea solution concentration is abnormal; otherwise, it is determined that the urea solution concentration is normal.

[0053] In some optional embodiments, the urea concentration is collected by a urea concentration sensor; if the concentration of nitrogen oxides is not in an upward trend within the first preset time length, the abnormality monitoring module is further configured to:

[0054] After a second preset time length, a new target concentration is determined again, and if the new target concentration is less than the preset concentration, it is determined that the urea concentration sensor has a detection fault.

[0055] In some optional embodiments, the method further comprises a monitoring follow-up module configured to:

[0056] After the abnormality monitoring module determines whether the urea solution concentration is abnormal, if the urea solution concentration is normal, after the urea level signal of the urea tank rises, it is determined again whether the urea solution concentration is abnormal; or

[0057] If the urea solution concentration is abnormal, information representing urea concentration abnormality is notified through a preset notification manner, and real-time target concentrations are monitored; if the real-time target concentrations are all greater than or equal to a preset concentration within a third preset time length, it is determined that the urea solution concentration abnormality is recovered.

[0058] In a third aspect, an electronic device is provided, comprising a processor and a memory.

[0059] The memory stores program codes, which, when executed by the processor, cause the processor to perform the urea concentration abnormality monitoring method according to any one of the first aspect.

[0060] In a fourth aspect, an embodiment of the present application provides a computer readable storage medium, which stores a computer program. When the computer program is executed by a processor, the urea concentration abnormality monitoring method according to any one of the first aspect is implemented.

[0061] In addition, the technical effects brought by any one of the implementation manners of the second aspect to the fourth aspect can refer to the technical effects brought by different implementation manners of the first aspect, which will not be described here. BRIEF DESCRIPTION OF DRAWINGS

[0062] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0063] Figure 1 The first urea concentration abnormality monitoring method provided by the embodiment of the present application is shown in the schematic flow chart.

[0064] Figure 2 The sliding window provided by the embodiment of the present application is shown in the schematic diagram.

[0065] Figure 3 The second urea concentration abnormality monitoring method provided by the embodiment of the present application is shown in the schematic flow chart.

[0066] Figure 4 The third urea concentration abnormality monitoring method provided by the embodiment of the present application is shown in the schematic flow chart.

[0067] Figure 5 The fourth urea concentration abnormality monitoring method provided by the embodiment of the present application is shown in the schematic flow chart.

[0068] Figure 6 The fifth urea concentration abnormality monitoring method provided by the embodiment of the present application is shown in the schematic flow chart.

[0069] Figure 7 The structure schematic diagram of the urea concentration abnormality monitoring device provided by the embodiment of the present application is shown in the schematic diagram.

[0070] Figure 8 The schematic block diagram of the electronic device provided by the embodiment of the present application is shown in the schematic block diagram. DETAILED DESCRIPTION

[0071] In order to make the purposes, technical solutions and advantages of the present application clearer, the following further describes the present application with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of the present application.

[0072] The terms "first", "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise specified and limited.

[0073] In the description of the present application, unless otherwise explicitly specified and limited, the term "connection" should be understood broadly, for example, it can be direct connection or indirect connection through an intermediate medium, and it can be internal communication of two devices. For those of ordinary skill in the art, the specific meaning of the above term in the present application can be understood according to the specific circumstances.

[0074] Nitrogen oxides exist in the exhaust gas of a vehicle, which will cause environmental pollution. In order to reduce the emission of nitrogen oxides, urea solution (a solution prepared by urea and water) is sprayed through a urea injection system, and the urea solution reacts with nitrogen oxides to decompose. The urea concentration will affect the decomposition effect, so it is necessary to monitor the urea concentration anomaly in time.

[0075] Some embodiments use ultrasonic technology to collect the urea solution concentration through a urea concentration sensor, and directly monitor the anomaly based on the urea solution concentration.

[0076] However, there are often bubbles in the urea solution, such as bubbles generated by shaking of the urea solution during vehicle driving, bubbles generated by the urea solution itself due to temperature rise and temperature drop, and bubbles generated during urea filling. When the bubbles adhere to the surface of the probe of the urea concentration sensor, they will affect the monitoring result, so the above method is difficult to accurately monitor the concentration anomaly.

[0077] In addition, some other embodiments determine whether the urea concentration is abnormal based on the nitrogen oxide conversion efficiency.

[0078] However, there are many factors affecting the nitrogen oxide conversion efficiency, and only relying on it to monitor the concentration anomaly will have a large deviation.

[0079] Still some other embodiments refer to the vehicle speed signal of the vehicle, and when there is a vehicle speed (bubbles are easy to generate during driving), the urea concentration is not diagnosed.

[0080] However, this way cannot be applied to the scene without a vehicle speed signal, and cannot be monitored before the vehicle drives.

[0081] Based on this, the embodiments of the present application provide a urea concentration abnormality monitoring method and device, electronic equipment and storage medium, the method comprising: in response to a monitoring instruction, determining whether the urea concentration of any collection time is valid according to the comparison result of the sound speed signal of the collection time and the sound speed signal of the last collection time; wherein the urea concentration is the collection concentration of the urea solution in the urea tank; based on the number of valid urea concentrations in the sliding window, determining whether the sliding window is valid, and determining all urea concentrations in the valid sliding window as reference concentrations; wherein the sliding window contains N consecutive collection times; based on the target concentration corresponding to the reference concentration, determining whether the urea solution is abnormal in concentration.

[0082] The above scheme, since the sound speed signal is obtained based on the transmission time and the receiving time, therefore, when there are bubbles and no bubbles in the urea solution, the sound speed signal will be different; by comparing the sound speed signals of the two adjacent collection times before and after, it can be determined whether the corresponding urea concentration is valid; further, based on the urea concentrations of the continuous multiple collection times in the sliding window, it is determined whether the overall concentration in the sliding window is valid, and the urea concentration in the valid sliding window is less affected by the bubbles; therefore, all urea concentrations in the valid sliding window are determined as reference concentrations, and then based on the target concentration corresponding to the reference concentration, it can be accurately determined whether the urea solution is abnormal in concentration, reducing the misjudgment and wrong judgment of concentration abnormality due to bubbles in the solution.

[0083] The technical solutions of the present application and how the technical solutions of the present application solve the above technical problems will be described in detail below with reference to the drawings and specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described in detail in some embodiments.

[0084] The embodiments of the present application provide a first urea concentration abnormality monitoring method, applied to an electronic device, such as an electronic control unit (ECU) in a vehicle, as shown in the figure, which can include: Figure 1 As shown in the figure, the method can include:

[0085] Step S101: in response to a monitoring instruction, determining whether the urea concentration of any collection time is valid according to the comparison result of the sound speed signal of the collection time and the sound speed signal of the last collection time.

[0086] The urea concentration is the collection concentration of the urea solution in the urea tank.

[0087] In a vehicle, a urea tank is arranged for storing urea solution; when a sensor of the urea tank is normally powered on, relevant parameters of the urea solution can be collected; for example, the concentration of the urea solution is collected by a urea concentration sensor, the urea liquid level signal is collected by a urea liquid level sensor, and the ultrasonic sound speed signal is collected by a sound speed sensor.

[0088] Since the sound speed signal is obtained based on the transmission time and the reception time, the sound speed signal will be different when there are bubbles in the urea solution and when there are no bubbles; by comparing the sound speed signals at two adjacent collection time points, it can be determined whether the corresponding urea concentration is valid.

[0089] The monitoring instruction in the embodiment is not specifically limited, such as an instruction triggered by power-on of the vehicle or a monitoring instruction triggered by a person.

[0090] Step S102: determining whether the sliding window is valid based on the number of valid urea concentrations in the sliding window, and determining all urea concentrations in the valid sliding window as reference concentrations.

[0091] The sliding window includes consecutive N collection time points, and in the implementation, the specific value of N can be set according to the actual application scenario.

[0092] In the implementation, the bubbles in the urea solution can be relatively stable and will not immediately dissipate, so that the sound speed signals at adjacent collection time points cannot be accurately determined whether they are affected by bubbles.

[0093] Based on this, the embodiment adopts a sliding window manner, determines whether the sliding window as a whole is valid based on the urea concentrations at consecutive N collection time points in the sliding window, the urea concentrations in the valid sliding window are less affected by bubbles, and all urea concentrations in the valid sliding window are determined as reference concentrations; the urea concentrations in the invalid sliding window are greatly affected by bubbles, and the urea concentrations in the invalid sliding window are not determined as reference concentrations for the time being, and the valid sliding window is continuously determined by using the first-in-first-out principle of the window.

[0094] Referring to Figure 2 As shown in the figure, 1 represents that the corresponding urea concentration is invalid, and 0 represents that the corresponding urea concentration is valid; the sliding window includes consecutive N collection time points, the urea concentration at collection time point 1 is valid (0), the urea concentration at collection time point 2 is valid (0), the urea concentration at collection time point 3 is invalid (1), the urea concentration at collection time point 4 is invalid (1), and so on, and the urea concentration at collection time point N is valid (0).

[0095] If the current is a valid sliding window, the urea concentrations corresponding to collection time points 1 to N are determined as reference concentrations, and the sliding window is continuously moved to the right.

[0096] If the current sliding window is invalid, the urea concentrations corresponding to the collection time 1-N are not determined as the reference concentrations, but the sliding is continued to the right to determine whether the collection time 2-N+1 corresponds to a valid sliding window.

[0097] In this example, the number of valid urea concentrations in the sliding window, that is, the number of 0s, the sum of the flag values of the sliding window is the number of invalid urea concentrations, and N-the sum of the flag values is the number of valid urea concentrations.

[0098] The above Figure 2 It is only an illustrative example, and in implementation, the urea concentration can be marked as valid or invalid by other ways, or other sliding methods can be used.

[0099] Step S103: determining whether the urea solution is abnormal in concentration based on the target concentration corresponding to the reference concentration.

[0100] All reference concentrations are relatively stable as a whole, but the reference concentrations are multiple values and cannot be directly monitored for concentration abnormalities; based on this, the reference concentration corresponding to the target concentration is determined, and then whether the urea solution is abnormal in concentration is determined based on the target concentration.

[0101] The above scheme, since the sound velocity signal is obtained based on the transmission time and the reception time, therefore, when there are bubbles and no bubbles in the urea solution, the sound velocity signals will be different; by comparing the sound velocity signals of the two adjacent collection times, it can be determined whether the corresponding urea concentration is valid; further, based on the urea concentrations of the continuous multiple collection times in the sliding window, it is determined whether the overall concentration in the sliding window is valid, and the urea concentration in the valid sliding window is less affected by the bubbles; therefore, all urea concentrations in the valid sliding window are determined as the reference concentrations, and then based on the target concentration corresponding to the reference concentration, it can be accurately determined whether the urea solution is abnormal in concentration, reducing the occurrence of false judgment and wrong judgment of concentration abnormalities due to bubbles in the solution.

[0102] In some optional embodiments, the above step S101 can be implemented by but not limited to the following ways:

[0103] determining the sound velocity difference between the sound velocity signal of the collection time and the sound velocity signal of the previous collection time;

[0104] If the sound velocity difference is less than a preset difference, it is determined that the urea concentration of the collection time is valid; otherwise, it is determined that the urea concentration of the collection time is invalid.

[0105] In implementation, when there are bubbles and no bubbles in the urea solution, the sound velocity signals will be different; if the difference between the sound velocity signals is greater, it means that the probability of the existence of bubbles is also greater;

[0106] Based on this, the embodiment determines the sound speed difference value between the sound speed signal at any collection moment and the sound speed signal at the previous collection moment, which reflects the difference between the two sound speed signals; then the sound speed difference value is compared with the preset difference value; if the sound speed difference value is less than the preset difference value, it means that the difference between the sound speed signal at the collection moment and the sound speed signal at the previous collection moment is small, and the probability of the existence of bubbles in the urea solution is low, and it is determined that the urea concentration at the collection moment is effective; otherwise, if the sound speed difference value is greater than or equal to the preset difference value, it means that the difference between the sound speed signal at the collection moment and the sound speed signal at the previous collection moment is large, and the probability of the existence of bubbles in the urea solution is large, and it is determined that the urea concentration at the collection moment is invalid.

[0107] For example, the sound speed signal Vt at the tth moment t and the sound speed signal Vt-1 at the (t-1)th moment t-1 are subtracted, and the absolute value after subtraction is determined as the sound speed difference value ΔVt, that is, ΔVt = |Vt-Vt-1|. t t-1 Then ΔVt is compared with the preset difference value Vb; if ΔVt≥Vb, the urea concentration at the tth moment is invalid, and if ΔVt

[0108] The above scheme, the greater the difference between the sound speed signals, the greater the probability of the existence of bubbles in the urea solution, by determining the sound speed difference value between the sound speed signal at any collection moment and the sound speed signal at the previous collection moment, and then comparing the sound speed difference value with the preset difference value; if the sound speed difference value is less than the preset difference value, it means that the difference between the sound speed signal at the collection moment and the sound speed signal at the previous collection moment is small, and the probability of the existence of bubbles in the urea solution is low, and it is determined that the urea concentration at the collection moment is effective; otherwise, if the sound speed difference value is greater than or equal to the preset difference value, it means that the difference between the sound speed signal at the collection moment and the sound speed signal at the previous collection moment is large, and the probability of the existence of bubbles in the urea solution is large, and it is determined that the urea concentration at the collection moment is invalid, so as to accurately determine the effectiveness of each urea concentration.

[0109] In some optional embodiments, the above step S102 can be implemented by but not limited to the following manner:

[0110] If the number of effective urea concentrations in the sliding window is greater than or equal to the preset number, it is determined that the sliding window is effective; otherwise, it is determined that the sliding window is invalid.

[0111] As described above, the bubbles in the urea solution can be relatively stable and will not immediately dissipate, and it is necessary to determine whether the sliding window as a whole is effective based on the urea concentrations at the continuous N collection moments in the sliding window.

[0112] Still referring to the above Figure 2 ​For example, 1 represents that the corresponding urea concentration is invalid, and 0 represents that the corresponding urea concentration is valid. The number of valid urea concentrations in the sliding window, that is, the number of 0, is the sum of the mark values of the sliding window S0, and N-S0 is the number of valid urea concentrations.

[0113] In the implementation, two preset numbers can be set. If the number of valid urea concentrations in the sliding window is greater than or equal to the first preset number, it is determined that the sliding window is valid; or if the number of invalid urea concentrations (S0) in the sliding window is less than the second preset number, it is determined that the sliding window is valid.

[0114] In the embodiment, if the number of valid urea concentrations in the sliding window is greater than or equal to the preset number, it indicates that the fluctuation of the sound speed signal in this period of time is not large, and the overall is relatively stable. It is determined that the sliding window is valid, and the urea concentration in the sliding window can be used as a basis for subsequent anomaly determination. Conversely, if the number of valid urea concentrations in the sliding window is less than the preset number, it indicates that the fluctuation of the sound speed signal in this period of time is large, and the overall is not stable enough. It is very likely to be affected by bubbles. Therefore, it is determined that the sliding window is invalid, and the urea concentration in the sliding window is not used as a basis for subsequent anomaly determination, thereby reducing the false positive probability.

[0115] Correspondingly, the embodiment of the present application provides a second urea concentration anomaly monitoring method, as shown in Figure 3 The method can include the following steps:

[0116] Step S301: In response to a monitoring instruction, determining a sound speed difference value between the sound speed signal at the collection time and the sound speed signal at the previous collection time.

[0117] Step S302: Determining whether the sound speed difference value is less than a preset difference value.

[0118] If yes, step S303 is performed, otherwise step S304 is performed.

[0119] Step S303: Determining that the urea concentration at the collection time is valid.

[0120] Step S304: Determining that the urea concentration at the collection time is invalid.

[0121] Step S305: Determining whether the number of valid urea concentrations in the sliding window is less than a preset number.

[0122] If yes, step S306 is performed, otherwise step S307 is performed.

[0123] Step S306: Determining that the sliding window is invalid.

[0124] Step S307: Determining that the sliding window is valid.

[0125] The specific implementation of steps S301-S307 can refer to the above embodiments, which will not be described here.

[0126] In some optional embodiments, the target concentration corresponding to the reference concentration is determined by the following method:

[0127] According to the reverse order of the collection time corresponding to the reference concentration, M reference concentrations are selected from all reference concentrations.

[0128] The M reference concentrations are filtered and calculated to obtain the target concentration corresponding to the reference concentration.

[0129] As described above, the reference concentration is a plurality of values, which cannot be directly monitored for concentration abnormalities, and the target concentration corresponding to the reference concentration needs to be determined. If all reference concentrations are considered, not only the calculation amount is large, but also the urea concentration that is time-distant cannot reflect the current urea state, which will affect the abnormal determination result.

[0130] Therefore, in the embodiment, the M latest collected reference concentrations are selected from all reference concentrations, and the M reference concentrations are filtered and calculated to reduce the interference of outliers and obtain the target concentration representing the current urea state.

[0131] The embodiment does not limit the specific value of M, and in the implementation, M can be greater than, less than or equal to N. For example, if M>N, the M reference concentrations need to be selected from the reference concentrations of the plurality of valid sliding windows; if M=N, all reference concentrations in the last valid sliding window are selected; and if M

[0132] The above scheme selects the M latest collected reference concentrations from all reference concentrations, and then filters and calculates the M reference concentrations to efficiently obtain the target concentration representing the current urea state, reduce the interference of historical states, and reduce the calculation amount.

[0133] The embodiment of the application provides a third urea concentration abnormality monitoring method, as shown in Figure 4 The method can include:

[0134] Step S401: In response to a monitoring instruction, determining whether the urea concentration at any collection time is valid according to the comparison result of the sound velocity signal at the collection time and the sound velocity signal at the previous collection time.

[0135] Step S402: Determining whether the sliding window is valid based on the number of valid urea concentrations in the sliding window, and determining all urea concentrations in the valid sliding window as reference concentrations.

[0136] The specific implementation of steps S401-S402 can refer to the above embodiments, which will not be described here.

[0137] Step S403: Determine whether the target concentration corresponding to the reference concentration is greater than or equal to a preset concentration.

[0138] If yes, step S404 is executed; otherwise, step S405 is executed.

[0139] In this embodiment, the target concentration represents the current urea solution state, and the preset concentration represents the allowable lower limit of the urea concentration. By comparing the target concentration with the preset concentration, if the target concentration is greater than or equal to the preset concentration, it indicates that the current urea solution concentration is normal, and step S404 is executed.

[0140] If the target concentration is less than the preset concentration, it indicates that the solution concentration collected by the urea concentration sensor is low, and the emission effect needs to be combined to execute step S405. After the urea injection system injects the urea solution based on the calibrated injection amount for a first preset time length, whether the urea solution concentration is abnormal is determined based on the concentration of nitrogen oxides in the first preset time length.

[0141] Step S404: Determine that the urea solution concentration is normal.

[0142] Step S405: After the urea injection system injects the urea solution based on the calibrated injection amount for a first preset time length, whether the urea solution concentration is abnormal is determined based on the concentration of nitrogen oxides in the first preset time length.

[0143] In the implementation, after the urea is injected for a first preset time length, the concentration of nitrogen oxides in the first preset time length reflects the decomposition effect. When other influencing factors remain unchanged, the lower the concentration of the urea solution, the worse the decomposition effect. Therefore, based on the concentration of nitrogen oxides in the first preset time length, whether the urea solution concentration is abnormal can be deduced.

[0144] The above scheme, since the target concentration represents the current urea solution state, and the preset concentration represents the allowable lower limit of the urea concentration. By comparing the target concentration with the preset concentration; if the target concentration is greater than or equal to the preset concentration, it indicates that the current urea solution concentration is normal; if the target concentration is less than the preset concentration, it indicates that the solution concentration collected by the urea concentration sensor is low, and the urea solution concentration is not directly determined to be abnormal, but is further judged in combination with the emission effect, which further improves the accuracy of abnormal monitoring and reduces the occurrence of misjudgment and wrong judgment of concentration abnormality.

[0145] The fourth urea concentration abnormality monitoring method provided in the embodiments of the present application is as shown in Figure 5 The method can include:

[0146] Step S501: In response to the monitoring instruction, determining whether the urea concentration at the current collection time is valid according to the comparison result of the sound speed signal at the current collection time and the sound speed signal at the previous collection time.

[0147] Step S502: Determining whether the sliding window is valid based on the number of valid urea concentrations in the sliding window, and determining all urea concentrations in the valid sliding window as reference concentrations.

[0148] Step S503: Determining whether the target concentration corresponding to the reference concentration is greater than or equal to the preset concentration.

[0149] If yes, step S504 is performed; otherwise, step S505 is performed.

[0150] Step S504: Determining that the urea solution concentration is normal.

[0151] The specific implementation of steps S501-S504 can refer to the above embodiments, which will not be described here.

[0152] Step S505: After the urea injection system injects the urea solution based on the calibrated injection amount for a first preset time, determining whether the concentration of nitrogen oxides is in an upward trend within the first preset time.

[0153] If yes, step S506 is performed; otherwise, step S507 is performed.

[0154] In implementation, after injecting urea for a first preset time, the concentration of nitrogen oxides within the first preset time reflects the decomposition effect. When other factors remain unchanged, the lower the concentration of the urea solution, the worse the decomposition effect. If it is determined that the concentration of nitrogen oxides is in an upward trend within the first preset time, it indicates that the decomposition effect is poor, and it is determined that the urea solution concentration is abnormal; if it is determined that the concentration of nitrogen oxides is not in an upward trend within the first preset time, it indicates that the urea concentration does not affect the decomposition effect, and it is determined that the urea solution concentration is normal.

[0155] In this embodiment, the determination of whether the concentration of nitrogen oxides is in an upward trend is not specifically limited, such as:

[0156] 1. Comparing the concentration of nitrogen oxides at the start time of the first preset time (first concentration) with the concentration of nitrogen oxides at the end time of the first preset time (second concentration), and if the first concentration is less than the second concentration, it is determined that the concentration of nitrogen oxides is in an upward trend;

[0157] 2. Based on the concentration curve of nitrogen oxides within the first preset time, if the overall trend of the concentration curve is rising (consisting of a series of rising trends, each rising trend continuously passes through the previous high point), it is determined that the concentration of nitrogen oxides is in an upward trend.

[0158] The two ways of determining whether the concentration of nitrogen oxides is in an increasing trend are only illustrative, and the present embodiment is not limited in this regard.

[0159] Step S506: determining that the concentration of the urea solution is abnormal.

[0160] Step S507: determining that the concentration of the urea solution is normal.

[0161] If the target concentration is less than the preset concentration, it indicates that the concentration of the solution collected by the urea concentration sensor is low, and the urea solution concentration is not directly determined to be abnormal, but further determination is made in combination with the emission effect; if it is determined that the concentration of nitrogen oxides is in an increasing trend within the first preset time length, it indicates that the decomposition effect is poor, and only then is the urea solution concentration determined to be abnormal, so as to accurately monitor the concentration abnormality.

[0162] The fifth urea concentration abnormality monitoring method provided by the present embodiment is as shown in the following table: Figure 6 The method can include the following steps:

[0163] Step S601: in response to a monitoring instruction, determining whether the urea concentration at any collection time is valid according to the comparison result of the sound velocity signal at the collection time and the sound velocity signal at the previous collection time.

[0164] Step S602: determining whether the sliding window is valid based on the number of valid urea concentrations in the sliding window, and determining all urea concentrations in the valid sliding window as reference concentrations.

[0165] Step S603: determining whether the target concentration corresponding to the reference concentration is greater than or equal to a preset concentration.

[0166] If yes, step S604 is performed; otherwise, step S605 is performed.

[0167] Step S604: determining that the concentration of the urea solution is normal.

[0168] Step S605: after the urea injection system injects the urea solution based on the calibrated injection amount for a first preset time length, determining whether the concentration of nitrogen oxides is in an increasing trend within the first preset time length.

[0169] If yes, step S606 is performed; otherwise, step S607 is performed.

[0170] Step S606: determining that the concentration of the urea solution is abnormal.

[0171] The specific implementation of steps S601-S606 can refer to the above embodiments, which will not be described here.

[0172] Step S607: determining that the urea solution concentration is normal, and re-determining a new target concentration after a second preset time length, and determining that the urea concentration sensor has a detection fault if the new target concentration is less than the preset concentration.

[0173] As described above, the target concentration is less than the preset concentration, indicating that the solution concentration collected by the urea concentration sensor is low; and the concentration of nitrogen oxides is not in an upward trend, indicating that the urea concentration does not affect the decomposition effect. In this case, it is indicated that the solution concentration collected by the urea concentration sensor may have some errors, which may be caused by bubbles or a fault of the urea concentration sensor itself.

[0174] Based on this, the embodiment needs to re-determine a new target concentration after a second preset time length when the target concentration is less than the preset concentration and the concentration of nitrogen oxides is not in an upward trend within a first preset time length. Since the bubbles in the urea solution do not exist all the time, if the new target concentration is still less than the preset concentration, it is determined that the urea concentration sensor has a detection fault.

[0175] The above scheme, if the target concentration is less than the preset concentration (indicating that the concentration is low), and the concentration of nitrogen oxides is not in an upward trend (indicating that the concentration is normal) within a first preset time length, it is indicated that the solution concentration collected by the urea concentration sensor may have some errors, which may be caused by bubbles or a fault of the urea concentration sensor itself. Since the bubbles in the urea solution do not exist all the time, a new target concentration is re-determined after a second preset time length, and if the new target concentration is still less than the preset concentration, it is determined that the urea concentration sensor has a detection fault.

[0176] In the implementation, after it is determined that the urea concentration sensor has a detection fault, a message representing the detection fault can be notified, so that relevant personnel can timely repair the urea concentration sensor, so as to collect more accurate solution concentration in the future.

[0177] In some optional embodiments, after it is determined whether the urea solution concentration is abnormal, the following steps are further performed:

[0178] If the urea solution concentration is normal, the urea solution concentration is re-determined after the urea liquid level signal of the urea tank rises; or

[0179] If the urea solution concentration is abnormal, information representing the urea concentration abnormality is notified through a preset notification mode, and real-time target concentration is monitored. If the real-time target concentration is greater than or equal to the preset concentration within a third preset time length, it is determined that the urea solution concentration abnormality is recovered.

[0180] In this embodiment, if the urea solution concentration is normal and no new urea solution is added to the urea tank, the concentration of the urea solution will usually not change significantly. Therefore, the real-time target concentration is no longer monitored to avoid the impact of air bubbles generated by vehicle shaking on the collection of urea concentration.

[0181] When adding new urea solution to the urea tank, the concentration of the urea solution may change. Therefore, after the urea level signal in the urea tank rises, it is necessary to re-determine whether the concentration of the urea solution is abnormal. The process of re-determining whether the concentration of the urea solution is abnormal can be referred to the above embodiment, and will not be repeated here.

[0182] If the urea solution concentration is abnormal, a pre-set notification method is needed to notify the information indicating the abnormal urea concentration (fault reporting) so that relevant personnel can handle the urea solution in the urea tank and monitor the real-time target concentration to know whether the abnormal urea concentration has been restored.

[0183] If the target concentration is greater than or equal to the preset concentration in real time within the third preset time period, that is, the duration for which the target concentration is greater than the preset concentration has reached the third preset time period, it means that the abnormal urea concentration has been recovered; if the target concentration is always less than the preset concentration, or the duration for which the target concentration is greater than or equal to the preset concentration is less than the third preset time period, it means that the urea concentration is still in an abnormal state, and the fault continues to be reported.

[0184] For example, after the urea concentration recovers from an abnormality, the real-time target concentration is no longer monitored. After the urea level signal in the urea tank rises, it is re-determined whether the urea solution concentration is abnormal.

[0185] In the above scheme, if the urea solution concentration is normal and no new urea solution is added to the urea tank, the urea solution concentration usually does not change significantly. Therefore, real-time target concentration monitoring is no longer required to avoid the impact of air bubbles generated by vehicle movement on urea concentration collection. Only after the urea level signal in the urea tank rises is the urea solution concentration reassessed to determine if it is abnormal. This reduces the impact of air bubbles and allows for timely monitoring of whether substandard urea solution has been added. If the urea solution concentration is abnormal, the information indicating the abnormal urea concentration is reported (fault reporting) so that relevant personnel can handle the urea solution in the tank and monitor the real-time target concentration to determine if the abnormal urea concentration has been resolved. If the real-time target concentration is greater than or equal to the preset concentration for a period of time within the third preset time, meaning the duration of the target concentration being greater than the preset concentration has reached the third preset time, it indicates that the abnormal urea concentration has been resolved.

[0186] like Figure 7 As shown, based on the same inventive concept, this application provides a urea concentration abnormality monitoring device 700, comprising:

[0187] an effectiveness determination module 701, configured to determine, in response to the monitoring instruction, whether the urea concentration at the current collection time is effective according to a comparison result of the sound speed signal at the current collection time and the sound speed signal at the previous collection time, wherein the urea concentration is a collection concentration of urea solution in a urea tank;

[0188] The effectiveness determination module 701 is further configured to determine whether the sliding window is effective based on a number of effective urea concentrations in the sliding window, and determine all urea concentrations in the effective sliding window as reference concentrations, wherein the sliding window comprises consecutive N collection times.

[0189] an abnormality monitoring module 702, configured to determine whether the urea solution is abnormal in concentration based on a target concentration corresponding to the reference concentration.

[0190] In some optional embodiments, the effectiveness determination module 701 is specifically configured to:

[0191] determine a sound speed difference between the sound speed signal at the current collection time and the sound speed signal at the previous collection time.

[0192] If the sound speed difference is less than a preset difference, it is determined that the urea concentration at the current collection time is effective; otherwise, it is determined that the urea concentration at the current collection time is ineffective.

[0193] In some optional embodiments, the effectiveness determination module 701 is specifically configured to:

[0194] If the number of effective urea concentrations in the sliding window is greater than or equal to a preset number, it is determined that the sliding window is effective; otherwise, it is determined that the sliding window is ineffective.

[0195] In some optional embodiments, the target concentration corresponding to the reference concentration is determined by:

[0196] selecting M reference concentrations from all reference concentrations in a reverse order of collection times corresponding to the reference concentrations.

[0197] performing filtering calculation on the M reference concentrations to obtain the target concentration corresponding to the reference concentration.

[0198] In some optional embodiments, the abnormality monitoring module 702 is specifically configured to:

[0199] If the target concentration is greater than or equal to a preset concentration, it is determined that the urea solution is normal in concentration.

[0200] Otherwise, after the urea injection system injects the urea solution for a first preset time based on the calibrated injection volume, it is determined whether the concentration of the urea solution is abnormal based on the concentration of nitrogen oxides within the first preset time.

[0201] In some optional implementations, the anomaly monitoring module 702 is specifically used for:

[0202] If the concentration of nitrogen oxides shows an upward trend within the first preset time period, the concentration of urea solution is determined to be abnormal; otherwise, the concentration of urea solution is determined to be normal.

[0203] In some optional embodiments, the urea concentration is collected by a urea concentration sensor; if the concentration of nitrogen oxides does not show an upward trend within the first preset time period, the anomaly monitoring module 702 is further configured to:

[0204] After a second preset time period, a new target concentration is determined. If the new target concentration is less than the preset concentration, it is determined that the urea concentration sensor has malfunctioned.

[0205] In some alternative implementations, a monitoring and follow-up module 703 is also included, for:

[0206] After the anomaly monitoring module determines whether the urea solution concentration is abnormal, if the urea solution concentration is normal, then after the urea level signal in the urea tank rises, the anomaly status of the urea solution concentration is reassessed; or

[0207] If the urea solution concentration is abnormal, information indicating the abnormal urea concentration will be notified via a preset notification method, and the real-time target concentration will be monitored; if the real-time target concentration is greater than or equal to the preset concentration within a third preset time period, it will be determined that the abnormal urea solution concentration has been restored.

[0208] Since this device is the same as the device in the method of this application embodiment, and the principle of the device in solving the problem is similar to that of the method, the implementation of the device can be referred to the implementation of the method, and the repeated parts will not be described again.

[0209] like Figure 8 As shown, based on the same inventive concept, this application provides an electronic device 800, including: a processor 801 and a memory 802;

[0210] Memory 802 may be volatile memory, such as random-access memory (RAM); memory 802 may also be non-volatile memory, such as read-only memory, flash memory, hard disk drive (HDD), or solid-state drive (SSD); or memory 802 may be any other medium capable of carrying or storing desired program code in the form of instructions or data structures and accessible by a computer, but is not limited thereto. Memory 802 may be a combination of the above-described memories.

[0211] The processor 801 may include one or more central processing units (CPUs), graphics processing units (GPUs), or digital processing units, etc.

[0212] This application embodiment does not limit the specific connection medium between the memory 802 and the processor 801. This application embodiment... Figure 8 The memory 802 and the processor 801 are connected via a bus 803, which is in... Figure 8 The bus 803, represented by thick lines, can be divided into address bus, data bus, control bus, etc. For ease of representation, Figure 8 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0213] The memory 802 stores program code, which, when executed by the processor 801, causes the processor 801 to perform the following processes:

[0214] In response to a monitoring command, the validity of the urea concentration at any given time is determined by comparing the sound velocity signal at any given time with the sound velocity signal at the previous time; wherein, the urea concentration is the concentration of the urea solution collected in the urea tank.

[0215] The validity of the sliding window is determined based on the number of valid urea concentrations within it, and all urea concentrations within the valid sliding window are defined as reference concentrations; wherein, the sliding window contains N consecutive acquisition times;

[0216] Based on the target concentration corresponding to the reference concentration, determine whether the urea solution has an abnormal concentration.

[0217] In some alternative implementations, the processor 801 specifically performs:

[0218] determining a sound speed difference between the sound speed signal of the collection time and a sound speed signal of a previous collection time;

[0219] if the sound speed difference is less than a preset difference, determining that the urea concentration of the collection time is valid; otherwise, determining that the urea concentration of the collection time is invalid.

[0220] In some optional embodiments, the processor 801 specifically performs:

[0221] if the number of valid urea concentrations in the sliding window is greater than or equal to a preset number, determining that the sliding window is valid; otherwise, determining that the sliding window is invalid.

[0222] In some optional embodiments, the target concentration corresponding to the reference concentration is determined by:

[0223] selecting M reference concentrations from all reference concentrations in descending order of the collection time corresponding to the reference concentration;

[0224] performing filtering calculation on the M reference concentrations to obtain the target concentration corresponding to the reference concentration.

[0225] In some optional embodiments, the processor 801 specifically performs:

[0226] if the target concentration is greater than or equal to a preset concentration, determining that the urea solution concentration is normal;

[0227] otherwise, after the urea injection system injects the urea solution based on the calibrated injection amount for a first preset time length, determining whether the urea solution concentration is abnormal based on the concentration of nitrogen oxides in the first preset time length.

[0228] In some optional embodiments, the processor 801 specifically performs:

[0229] if the concentration of nitrogen oxides is in an upward trend in the first preset time length, determining that the urea solution concentration is abnormal; otherwise, determining that the urea solution concentration is normal.

[0230] In some optional embodiments, the urea concentration is collected by a urea concentration sensor; if the concentration of nitrogen oxides is not in an upward trend in the first preset time length, the processor 801 further performs:

[0231] after a second preset time length, re-determining a new target concentration, and if the new target concentration is less than the preset concentration, determining that the urea concentration sensor has a detection fault.

[0232] In some optional embodiments, after determining whether the urea solution is abnormal in concentration, the processor 801 further performs:

[0233] If the urea solution is normal in concentration, after the urea level signal of the urea tank rises, it is determined again whether the urea solution is abnormal in concentration; or

[0234] If the urea solution is abnormal in concentration, information indicating that the urea solution is abnormal in concentration is notified through a preset notification mode, and the real-time target concentration is monitored; if the real-time target concentration is greater than or equal to the preset concentration within a third preset time length, it is determined that the urea solution is recovered from abnormality in concentration.

[0235] Since the electronic device is the electronic device for executing the method in the embodiments of the present application, and the principle of solving the problem of the electronic device is similar to that of the method, the implementation of the electronic device can be referred to the implementation of the method, and the repeated parts will not be described here.

[0236] The embodiments of the present application provide a computer readable storage medium, which stores a computer program, and the program is executed by a processor to implement the steps of the urea concentration abnormality monitoring method. The readable storage medium can be a non-volatile readable storage medium.

[0237] The embodiments of the present application are described above with reference to the block diagrams and / or flowcharts according to the embodiments of the present application. It should be understood that one block and the combination of blocks in the block diagrams and / or flowcharts can be implemented by computer program instructions. These computer program instructions can be provided to a general-purpose computer, a processor of a special-purpose computer, and / or other programmable devices to produce a machine, so that the instructions executed by the computer processor and / or other programmable devices create a method for implementing the functions / acts specified in the block diagrams and / or flowcharts.

[0238] Accordingly, the present application can also be implemented by hardware and / or software (including firmware, resident software, microcode, etc.). Furthermore, the present application can take the form of a computer program product on a computer usable or computer-readable storage medium having computer usable or computer-readable program code embodied in the medium that can be executed by a computer processing device. In this context, a computer usable or computer-readable medium can be any medium that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. The computer usable or computer-readable medium can be, for example but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, device, propagation medium, or computer medium.

[0239] While the preferred embodiments of the application have been described, additional variations and modifications can be made to these embodiments by those skilled in the art once they have the benefit of the present disclosure without departing from the spirit and scope of the application. Accordingly, it is intended that the appended claims include all such modifications and variations as fall within the scope of the present application.

[0240] Obviously, many modifications and variations of the present application are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims and their equivalents, the application can be practiced otherwise than as specifically described.

Claims

1. A method for monitoring abnormal urea concentration, characterized in that, The method includes: In response to a monitoring command, the validity of the urea concentration at any given time is determined by comparing the sound velocity signal at any given time with the sound velocity signal at the previous time; wherein, the urea concentration is the concentration of the urea solution collected in the urea tank. The validity of the sliding window is determined based on the number of valid urea concentrations within it, and all urea concentrations within the valid sliding window are defined as reference concentrations; wherein, the sliding window contains N consecutive acquisition times; Based on the target concentration corresponding to the reference concentration, determine whether the urea solution has an abnormal concentration; The target concentration corresponding to the reference concentration is determined in the following manner: Select M reference concentrations from all reference concentrations in reverse order of the collection times corresponding to the reference concentrations; The target concentration corresponding to the M reference concentrations is obtained by filtering and calculating the M reference concentrations.

2. The method according to claim 1, characterized in that, Based on the comparison between the sound velocity signal at any given time and the sound velocity signal at the previous time, the validity of the urea concentration at that time is determined, including: Determine the sound velocity difference between the sound velocity signal at the acquisition time and the sound velocity signal at the previous acquisition time; If the sound velocity difference is less than a preset difference, the urea concentration at the time of collection is determined to be valid; otherwise, the urea concentration at the time of collection is determined to be invalid.

3. The method according to claim 1, characterized in that, Determining whether the sliding window is effective based on the amount of effective urea concentration within the sliding window includes: If the effective urea concentration within the sliding window is greater than or equal to a preset quantity, the sliding window is determined to be effective; otherwise, the sliding window is determined to be ineffective.

4. The method according to claim 1, characterized in that, Based on the target concentration corresponding to the reference concentration, determining whether the urea solution has an abnormal concentration includes: If the target concentration is greater than or equal to the preset concentration, then the concentration of the urea solution is determined to be normal. Otherwise, after the urea injection system injects the urea solution for a first preset time based on the calibrated injection volume, it is determined whether the concentration of the urea solution is abnormal based on the concentration of nitrogen oxides within the first preset time.

5. The method according to claim 4, characterized in that, Based on the concentration of nitrogen oxides within the first preset time period, determining whether the urea solution has an abnormal concentration includes: If the concentration of nitrogen oxides shows an upward trend within the first preset time period, the concentration of urea solution is determined to be abnormal; otherwise, the concentration of urea solution is determined to be normal.

6. The method according to claim 5, characterized in that, The urea concentration was collected by a urea concentration sensor; If the concentration of nitrogen oxides does not show an increasing trend within the first preset time period, the method further includes: After a second preset time period, a new target concentration is determined. If the new target concentration is less than the preset concentration, it is determined that the urea concentration sensor has malfunctioned.

7. The method according to any one of claims 1 to 6, characterized in that, After determining whether the urea solution has an abnormal concentration, the process also includes: If the urea solution concentration is normal, then after the urea level signal in the urea tank rises, the concentration of the urea solution is reassessed to determine if it is abnormal; or If the urea solution concentration is abnormal, information indicating the abnormal urea concentration will be notified via a preset notification method, and the real-time target concentration will be monitored; if the real-time target concentration is greater than or equal to the preset concentration within a third preset time period, it will be determined that the abnormal urea solution concentration has been restored.

8. A device for monitoring abnormal urea concentration, characterized in that, The device includes: The validity determination module is used to respond to monitoring instructions and determine whether the urea concentration at any given time is valid based on the comparison result of the sound velocity signal at any given time with the sound velocity signal at the previous time; wherein, the urea concentration is the collection concentration of the urea solution in the urea tank. The validity determination module is further used to determine whether the sliding window is valid based on the number of valid urea concentrations within the sliding window, and to determine all urea concentrations within the valid sliding window as reference concentrations; wherein, the sliding window contains N consecutive acquisition times; An anomaly monitoring module is used to determine whether the urea solution has an abnormal concentration based on the target concentration corresponding to the reference concentration. The target concentration corresponding to the reference concentration is determined in the following manner: Select M reference concentrations from all reference concentrations in reverse order of the collection times corresponding to the reference concentrations; The target concentration corresponding to the M reference concentrations is obtained by filtering and calculating the M reference concentrations.

9. An electronic device, characterized in that, include: Processor and memory; The memory stores program code, which, when executed by the processor, causes the processor to perform the urea concentration anomaly monitoring method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, which, when executed by a processor, implements the urea concentration anomaly monitoring method as described in any one of claims 1 to 7.

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