Self-learning method and device for venturi differential pressure sensor characteristic curve

Abstract

This invention discloses a self-learning method and apparatus for the characteristic curve of a Venturi differential pressure sensor, comprising: acquiring vehicle operating conditions; determining the standard flow rate of an EGR valve when the vehicle operating conditions meet preset operating conditions; acquiring a first differential pressure value detected by the Venturi differential pressure sensor and a second differential pressure value based on the first differential pressure value after self-learning; determining a first flow rate of the EGR valve based on the first differential pressure value, determining a second flow rate of the EGR valve based on the second differential pressure value, and determining a first difference between the standard flow rate and the first flow rate, and a second difference between the standard flow rate and the second flow rate; and determining the characteristic curve of the Venturi differential pressure sensor based on the first difference and the second difference. This application compares the calculated standard flow rate of the EGR valve under set operating conditions with the EGR valve flow rate corresponding to the actual differential pressure value measured by the Venturi differential pressure sensor and the EGR valve flow rate corresponding to the self-learned differential pressure value. Based on the comparison results, it can determine whether to apply the self-learned characteristic curve, thereby improving the detection accuracy of the Venturi differential pressure sensor.

Description

Technical Field

[0001] This invention relates to the field of automotive engine EGR system technology, specifically to a self-learning method, device, electronic device, and storage medium for the characteristic curve of a Venturi differential pressure sensor. Background Technology

[0002] my country is a major automobile producer, and as people's living standards improve, automobile emissions are receiving increasing attention.

[0003] In some existing vehicle types, the Venturi differential pressure sensor of the EGR system may experience reduced detection accuracy due to vehicle operating conditions or external environmental factors when detecting differential pressure.

[0004] In one existing approach, the correction method for the Venturi differential pressure sensor involves detecting whether the difference between the differential pressure value at zero point and a preset value exceeds a limit when the device is stopped. If the limit is exceeded, self-learning is performed based on the over-limit condition. However, in actual use, the problem of inaccurate detection by the Venturi differential pressure sensor still occurs.

[0005] Therefore, the technical problem of how to improve the detection accuracy of Venturi differential pressure sensors urgently needs to be solved. Summary of the Invention

[0006] To address the technical problem described in the background section regarding how to improve the accuracy of Venturi differential pressure sensors, this invention proposes a self-learning method, apparatus, electronic device, and storage medium for the characteristic curve of a Venturi differential pressure sensor.

[0007] One objective of this invention is to propose a self-learning method for the characteristic curve of a Venturi differential pressure sensor. This method compares the calculated standard flow rate of the EGR valve under set operating conditions with the EGR valve flow rate corresponding to the measured differential pressure value of the Venturi differential pressure sensor and the EGR valve flow rate corresponding to the self-learned differential pressure value. Based on the comparison results, it can determine whether to apply the self-learned characteristic curve, thereby improving the detection accuracy of the Venturi differential pressure sensor.

[0008] Another objective of this application is to propose a self-learning device for the characteristic curve of a Venturi differential pressure sensor.

[0009] Another object of the present invention is to provide an electronic device.

[0010] Another object of the present invention is to provide a computer-readable storage medium.

[0011] According to one aspect of the embodiments of this application, a self-learning method for the characteristic curve of a Venturi differential pressure sensor is provided, comprising: acquiring vehicle operating conditions; determining a standard flow rate of an EGR valve when the vehicle operating conditions meet preset operating conditions; acquiring a first differential pressure value detected by the Venturi differential pressure sensor and a second differential pressure value based on the first differential pressure value through self-learning; determining a first flow rate of the EGR valve based on the first differential pressure value, determining a second flow rate of the EGR valve based on the second differential pressure value, and determining a first difference between the standard flow rate and the first flow rate, and a second difference between the standard flow rate and the second flow rate; and determining a characteristic curve of the Venturi differential pressure sensor based on the first difference and the second difference.

[0012] Optionally, determining the standard flow rate of the EGR valve when the vehicle operating conditions meet the preset operating conditions includes: building a flow model of the EGR valve; obtaining the detection values ​​of the front pressure sensor and the rear pressure sensor of the EGR valve and the opening value of the EGR valve, and determining a third pressure difference value between the front and rear pressures of the EGR valve based on the detection values; and determining the standard flow rate based on the flow model, the opening value, and the third pressure difference value.

[0013] Optionally, determining the characteristic curve of the Venturi differential pressure sensor based on the first difference and the second difference includes: when the first difference is less than the second difference, determining the characteristic curve corresponding to the first differential pressure as the characteristic curve of the Venturi differential pressure sensor; when the first difference is greater than the second difference, determining the characteristic curve corresponding to the second differential pressure as the characteristic curve of the Venturi differential pressure sensor.

[0014] Optionally, the self-learning method for the characteristic curve of the Venturi differential pressure sensor further includes: building a Venturi differential pressure model; determining a standard differential pressure based on the Venturi differential pressure model and the standard flow rate; determining a third difference based on the standard differential pressure and the first differential pressure value, and determining a fourth difference based on the standard differential pressure and the second differential pressure value; and determining the characteristic curve of the Venturi differential pressure sensor based on the third difference and the fourth difference.

[0015] Optionally, determining the characteristic curve of the Venturi differential pressure sensor based on the third difference and the fourth difference includes: when the third difference is greater than the fourth difference, determining the characteristic curve corresponding to the second differential pressure value as the characteristic curve of the Venturi differential pressure sensor; when the third difference is less than the fourth difference, determining the characteristic curve corresponding to the first differential pressure value as the characteristic curve of the Venturi differential pressure sensor.

[0016] Optionally, before acquiring the vehicle operating condition, the process includes: determining whether the 0 point of the differential pressure value detected by the Venturi differential pressure sensor has drifted when the vehicle is in a parked state; if a drift occurs, proceeding to the step of acquiring the vehicle operating condition.

[0017] Optionally, the self-learning method for the characteristic curve of the Venturi differential pressure sensor further includes the following steps: when the vehicle operating condition does not meet the preset operating condition, stop judging the vehicle operating condition, maintain it for a preset time, and then return to judging whether the differential pressure value 0 detected by the Venturi differential pressure sensor has drifted when the vehicle is in a parked state.

[0018] According to another aspect of the embodiments of this application, a self-learning device for the characteristic curve of a Venturi differential pressure sensor is also provided, comprising: a first acquisition module for acquiring vehicle operating conditions; a first analysis module for determining the standard flow rate of an EGR valve when the vehicle operating conditions meet preset operating conditions; a second acquisition module for acquiring a first differential pressure value detected by the Venturi differential pressure sensor and a second differential pressure value for self-learning based on the first differential pressure value; a second analysis module for determining a first flow rate of the EGR valve based on the first differential pressure value, determining a second flow rate of the EGR valve based on the second differential pressure value, and determining a first difference between the standard flow rate and the first flow rate, and a second difference between the standard flow rate and the second flow rate; and a third analysis module for determining the characteristic curve of the Venturi differential pressure sensor based on the first difference and the second difference.

[0019] According to another aspect of the embodiments of this application, an electronic device is also provided, including a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; wherein the memory is used to store a computer program; and the processor is used to execute the method steps of any of the above embodiments by running the computer program stored in the memory.

[0020] According to another aspect of the embodiments of this application, a computer-readable storage medium is also provided, wherein a computer program is stored therein, wherein the computer program is configured to execute the method steps of any of the above embodiments when running.

[0021] This application calculates the standard flow rate of the EGR valve under set operating conditions and compares it with the first flow rate of the EGR valve corresponding to the first differential pressure value measured by the Venturi differential pressure sensor and the second flow rate of the EGR valve corresponding to the second differential pressure value after self-learning based on the first differential pressure value. The comparison results are used to determine whether to apply the self-learning characteristic curve, thereby improving the detection accuracy of the Venturi differential pressure sensor. Attached Figure Description

[0022] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of an optional Venturi pressure differential characteristic curve according to an embodiment of this application;

[0025] Figure 2 This is a flowchart illustrating an optional self-learning method for the characteristic curve of a Venturi differential pressure sensor according to an embodiment of this application.

[0026] Figure 3 This is another flowchart illustrating an optional self-learning method for the characteristic curve of a Venturi differential pressure sensor according to an embodiment of this application.

[0027] Figure 4 This is a structural block diagram of an optional self-learning device for the characteristic curve of a Venturi differential pressure sensor according to an embodiment of this application.

[0028] Figure 5 This is a structural block diagram of an optional electronic device according to an embodiment of this application. Detailed Implementation

[0029] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0030] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0031] As described in the background section, in some existing vehicle types, the Venturi differential pressure sensor of the EGR system may experience reduced detection accuracy due to vehicle operating conditions or external environmental factors when detecting differential pressure.

[0032] In one existing approach, the correction method for the Venturi differential pressure sensor involves detecting whether the difference between the differential pressure value at zero point and a preset value exceeds a limit when the device is stopped. If the limit is exceeded, self-learning is performed based on the over-limit condition. However, in actual use, the problem of inaccurate detection by the Venturi differential pressure sensor still occurs.

[0033] See Figure 1 As shown, the Venturi differential pressure sensor self-learns by identifying its voltage in a stopped state and using this identified voltage to replace the zero point voltage of the preset value curve as the zero point of the differential pressure. Through this self-learning, the entire preset value curve can be shifted to another curve, i.e., the drifted curve, which is then used as the final characteristic curve of the Venturi differential pressure sensor, thereby improving its detection accuracy.

[0034] However, in actual use, the detection accuracy of the Venturi differential pressure sensor still sometimes falls short. Through testing, the inventors discovered that this might be due to the characteristic curve of the Venturi differential pressure sensor not drifting at a fixed slope. In a measured test of the characteristic curve of a Venturi differential pressure sensor, the characteristic curve was... Figure 1 This is referred to as "another drift curve". Therefore, directly applying the self-learned curve as the final characteristic curve of the Venturi differential pressure sensor will lead to inaccurate measurements.

[0035] Therefore, according to one aspect of the embodiments of this application, a self-learning method for the characteristic curve of a Venturi differential pressure sensor is provided, see [link to relevant documentation]. Figure 2 As shown, the process of this method may include the following steps:

[0036] S10. Obtain vehicle operating conditions.

[0037] S20. When the vehicle operating conditions meet the preset operating conditions, determine the standard flow rate of the EGR valve.

[0038] S30. Obtain the first differential pressure value detected by the Venturi differential pressure sensor and the second differential pressure value based on the first differential pressure value through self-learning.

[0039] S40. Determine the first flow rate of the EGR valve based on the first differential pressure value, determine the second flow rate of the EGR valve based on the second differential pressure value, and determine the first difference between the standard flow rate and the first flow rate, and the second difference between the standard flow rate and the second flow rate.

[0040] S50. Determine the characteristic curve of the Venturi differential pressure sensor based on the first difference and the second difference.

[0041] In this embodiment, the vehicle operating condition can be such that the current EGR valve pressure ratio before and after the EGR valve is within the model reliability range of the EGR valve throttling equation, and that the pressure sensors before and after the EGR valve, the EGR valve opening sensor, and the temperature sensor before the EGR valve are all functioning correctly. This ensures that the calculated standard flow rate is accurate when the vehicle operating condition meets the preset conditions. The standard flow rate of the EGR valve under the set operating conditions is calculated and compared with the first flow rate of the EGR valve corresponding to the first differential pressure value measured by the Venturi differential pressure sensor and the second flow rate of the EGR valve corresponding to the second differential pressure value after self-learning based on the first differential pressure value. A first difference and a second difference are obtained, and the final characteristic curve of the Venturi differential pressure sensor is determined based on these two differences—either the characteristic curve before self-learning or the characteristic curve after self-learning. Real-time detection is performed, updating the detection every time the vehicle is stationary, or updating it every preset number of stationary periods, to improve the detection accuracy of the Venturi differential pressure sensor. The preset number of periods can be a positive integer greater than or equal to 2.

[0042] The flow model is shown in equation (1):

[0043]

[0044] Where, q EGR For standard flow rate, β is the effective flow diameter of the EGR valve / the fully open diameter of the EGR valve, and A is the standard flow rate. EGR This refers to the effective flow area of ​​the EGR valve, ε refers to the compressibility coefficient, ρ0 refers to the density of the gas before the EGR valve, p0 refers to the pressure of the gas before the EGR valve, p1 refers to the pressure of the gas after the EGR valve, and k1 is a two-dimensional interpolation table based on rotational speed and load.

[0045] The calculation formulas for the first and second flow rates are shown in equation (2):

[0046]

[0047] Where β2 is the effective flow diameter of the EGR valve / the fully open diameter of the EGR valve, A Ven ε2 refers to the effective flow area of ​​the EGR valve, ρ0 refers to the density of the gas before the EGR valve, Δp refers to the pressure difference of the gas before and after the EGR valve, and k2 is a two-dimensional interpolation table based on rotational speed and load. Substituting the first differential pressure value detected by the Venturi differential pressure sensor and the second differential pressure value learned from the first differential pressure value into equation (2), the first flow rate and the second flow rate can be calculated, i.e., q in equation (2). EGR_ .

[0048] As an exemplary embodiment, determining the standard flow rate of the EGR valve when the vehicle operating conditions meet the preset operating conditions includes: building a flow model of the EGR valve; obtaining the detection values ​​of the front pressure sensor and the rear pressure sensor of the EGR valve and the opening value of the EGR valve, and determining a third pressure difference value of the front and rear pressures of the EGR valve based on the detection values; and determining the standard flow rate based on the flow model, the opening value, and the third pressure difference value.

[0049] In this embodiment, the opening value of the EGR valve can be detected by an EGR valve opening sensor. A flow model based on the EGR valve opening is built, and a third differential pressure value is determined by the upstream and downstream pressure sensors of the EGR valve. The standard flow rate is determined based on the flow model, the opening value, and the third differential pressure value. This avoids detecting the differential pressure by a Venturi differential pressure sensor, eliminates the influence of possible inaccurate detection caused by the Venturi differential pressure sensor, and improves the accuracy of the final curve determination.

[0050] As an exemplary embodiment, determining the characteristic curve of the Venturi differential pressure sensor based on the first difference and the second difference includes: when the first difference is less than the second difference, determining the characteristic curve corresponding to the first differential pressure as the characteristic curve of the Venturi differential pressure sensor; when the first difference is greater than the second difference, determining the characteristic curve corresponding to the second differential pressure as the characteristic curve of the Venturi differential pressure sensor.

[0051] In this embodiment, when the first difference is less than the second difference, the deviation between the standard flow rate and the first flow rate is small. That is, the deviation of the first differential pressure value measured by the Venturi differential pressure sensor is smaller than the deviation of the second differential pressure value learned from the first differential pressure value. Therefore, the measured first differential pressure value is more accurate. Thus, the characteristic curve corresponding to the first differential pressure value is used as the characteristic curve of the Venturi differential pressure sensor, i.e., the preset value curve before self-learning is used as the final characteristic curve of the Venturi differential pressure sensor. Conversely, when the first difference is greater than the second difference, the deviation between the standard flow rate and the second flow rate is small. That is, the deviation of the first differential pressure value measured by the Venturi differential pressure sensor is larger than the deviation of the second differential pressure value learned from the first differential pressure value. Therefore, the self-learned second differential pressure value is more accurate. Thus, the characteristic curve corresponding to the second differential pressure value is used as the characteristic curve of the Venturi differential pressure sensor, i.e., the drift curve after self-learning is used as the final characteristic curve of the Venturi differential pressure sensor. By comparing the first difference and the second difference, a differential pressure value with a smaller deviation from the actual situation can be determined, thereby determining the characteristic curve and improving the detection accuracy of the Venturi differential pressure sensor.

[0052] As an exemplary embodiment, the self-learning method for the characteristic curve of the Venturi differential pressure sensor further includes: building a Venturi differential pressure model; determining a standard differential pressure based on the Venturi differential pressure model and the standard flow rate; determining a third difference based on the standard differential pressure and the first differential pressure value; determining a fourth difference based on the standard differential pressure and the second differential pressure value; and determining the characteristic curve of the Venturi differential pressure sensor based on the third difference and the fourth difference.

[0053] In this embodiment, the standard flow rate and the measured flow rate of the EGR valve are known in advance. The characteristic curve of the Venturi differential pressure sensor can be determined not only by comparing the standard flow rate with the first and second flow rates, but also by using the detection value of the Venturi differential pressure sensor. Specifically, a Venturi differential pressure model is constructed, as shown in equation (3):

[0054]

[0055] Where Δp1 is the pressure difference value, q EGR2 The flow rate of the EGR valve is given by k3, which is a two-dimensional interpolation table based on speed and load, obtained experimentally. ε3 is the compressibility coefficient, which can be considered a constant within a scheduling cycle. Ven2 ρ0 is the effective flow area of ​​the Venturi throat; ρ0 is the density of the Venturi inlet; and β3 is the throat diameter / inlet diameter.

[0056] Substituting the standard flow rate into equation (3) yields the model pressure difference. The third and fourth differences between the standard pressure difference and the first and second pressure difference values ​​are calculated respectively. Similarly, based on the third and fourth differences, the characteristic curve of the Venturi pressure differential sensor can be determined.

[0057] As an exemplary embodiment, determining the characteristic curve of the Venturi differential pressure sensor based on the third difference and the fourth difference includes: when the third difference is greater than the fourth difference, determining the characteristic curve corresponding to the second differential pressure as the characteristic curve of the Venturi differential pressure sensor; when the third difference is less than the fourth difference, determining the characteristic curve corresponding to the first differential pressure as the characteristic curve of the Venturi differential pressure sensor.

[0058] In this embodiment, similar to the comparison of the first difference and the second difference, when the third difference is greater than the fourth difference, the characteristic curve corresponding to the second differential pressure value is the final characteristic curve of the Venturi differential pressure sensor, that is, the curve after self-learning is the final characteristic curve; when the third difference is less than the fourth difference, the characteristic curve corresponding to the first differential pressure value is the final characteristic curve of the Venturi differential pressure sensor, that is, the curve before self-learning is the final characteristic curve.

[0059] As an exemplary embodiment, the step of obtaining vehicle operating conditions includes: determining whether the pressure difference value 0 detected by the Venturi differential pressure sensor has drifted when the vehicle is in a parked state; if drift occurs, proceeding to the step of obtaining vehicle operating conditions.

[0060] In this embodiment, when the differential pressure value detected by the Venturi differential pressure sensor drifts at 0, it indicates that the detection accuracy of the Venturi differential pressure sensor has changed. At this time, it is necessary to re-detect and adjust the detection accuracy of the Venturi differential pressure sensor, and then proceed to the step of acquiring vehicle operating conditions.

[0061] As an exemplary embodiment, the self-learning method for the characteristic curve of the Venturi differential pressure sensor further includes the following steps: when the vehicle operating condition does not meet the preset operating condition, stopping the judgment of the vehicle operating condition, maintaining it for a preset time, and then returning to the judgment when the vehicle is in a parked state, to determine whether the pressure difference value 0 detected by the Venturi differential pressure sensor has drifted.

[0062] In this embodiment, if the vehicle's operating condition does not meet the preset operating condition due to external environmental factors, it is necessary to stop judging the vehicle's operating condition and maintain this stopped state for a preset time. After the preset time expires, the program corresponding to the self-learning method of the Venturi differential pressure sensor characteristic curve is re-run, that is, the step of judging whether the zero point of the differential pressure value detected by the Venturi differential pressure sensor has drifted when the vehicle is in a stopped state is entered, so as to avoid the influence of external environmental factors and detect the detection accuracy of the Venturi differential pressure sensor in real time.

[0063] According to another aspect of the embodiments of this application, a self-learning device for the characteristic curve of a Venturi differential pressure sensor is provided, see [link to relevant documentation]. Figure 4 As shown, it includes:

[0064] The first acquisition module 401 is used to acquire vehicle operating conditions;

[0065] The first analysis module 402 is used to determine the standard flow rate of the EGR valve when the vehicle operating conditions meet the preset operating conditions.

[0066] The second acquisition module 403 is used to acquire the first differential pressure value detected by the Venturi differential pressure sensor and the second differential pressure value based on the first differential pressure value through self-learning.

[0067] The second analysis module 404 determines the first flow rate of the EGR valve based on the first differential pressure value, determines the second flow rate of the EGR valve based on the second differential pressure value, and determines the first difference between the standard flow rate and the first flow rate, and the second difference between the standard flow rate and the second flow rate.

[0068] The third analysis module 405 determines the characteristic curve of the Venturi differential pressure sensor based on the first difference and the second difference.

[0069] It should be noted that the first acquisition module 401 in this embodiment can be used to perform the above step S10, the first analysis module 402 in this embodiment can be used to perform the above step S20, the second acquisition module 403 in this embodiment can be used to perform the above step S30, the second analysis module 404 in this embodiment can be used to perform the above step S40, and the third analysis module 405 in this embodiment can be used to perform the above step S50.

[0070] According to another aspect of the embodiments of this application, an electronic device is provided, including a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus, the memory is used to store a computer program, and the processor is used to execute the self-learning method for the characteristic curve of the Venturi differential pressure sensor described in any of the above embodiments by running the computer program stored in the memory.

[0071] Figure 5 This is a structural block diagram of an optional electronic device according to an embodiment of this application, such as... Figure 5 As shown, it includes a processor 502, a communication interface 504, a memory 506, and a communication bus 508. The processor 502, communication interface 504, and memory 506 communicate with each other via the communication bus 508.

[0072] Memory 506 is used to store computer programs;

[0073] When processor 502 executes a computer program stored in memory 506, it performs the following steps:

[0074] Obtain vehicle operating conditions;

[0075] When the vehicle operating conditions meet the preset operating conditions, determine the standard flow rate of the EGR valve;

[0076] Acquire a first differential pressure value detected by a Venturi differential pressure sensor and a second differential pressure value learned based on the first differential pressure value;

[0077] The first flow rate of the EGR valve is determined based on the first differential pressure value, the second flow rate of the EGR valve is determined based on the second differential pressure value, and the first difference between the standard flow rate and the first flow rate, and the second difference between the standard flow rate and the second flow rate are determined.

[0078] The characteristic curve of the Venturi differential pressure sensor is determined based on the first difference and the second difference.

[0079] Optionally, in this embodiment, the communication bus can be a PCI (Peripheral Component Interconnect) bus or an EISA (Extended Industry Standard Architecture) bus, etc. This communication bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 5 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.

[0080] The communication interface is used for communication between the aforementioned electronic devices and other devices.

[0081] The memory may include RAM, or non-volatile memory, such as at least one disk storage device. Optionally, the memory may also be at least one storage device located remotely from the aforementioned processor.

[0082] According to another aspect of the embodiments of this application, a computer-readable storage medium is provided, wherein a computer program is stored in the storage medium, and the computer program is configured to execute the self-learning method for the characteristic curve of the Venturi differential pressure sensor as described in any of the above embodiments when running.

[0083] Optionally, in this embodiment, the storage medium is configured to store program code for performing the following steps:

[0084] Obtain vehicle operating conditions;

[0085] When the vehicle operating conditions meet the preset operating conditions, determine the standard flow rate of the EGR valve;

[0086] Acquire a first differential pressure value detected by a Venturi differential pressure sensor and a second differential pressure value learned based on the first differential pressure value;

[0087] The first flow rate of the EGR valve is determined based on the first differential pressure value, the second flow rate of the EGR valve is determined based on the second differential pressure value, and the first difference between the standard flow rate and the first flow rate, and the second difference between the standard flow rate and the second flow rate are determined.

[0088] The characteristic curve of the Venturi differential pressure sensor is determined based on the first difference and the second difference.

[0089] Optionally, specific examples in this embodiment can refer to the examples described in the above embodiments, and will not be repeated in this embodiment.

[0090] Optionally, in this embodiment, the storage medium may include, but is not limited to, various media capable of storing program code, such as USB flash drives, ROMs, RAMs, portable hard drives, magnetic disks, or optical disks.

[0091] The sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0092] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that this application is not limited to the described order of actions, as some steps may be performed in other orders or simultaneously according to this application. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions and modules involved are not necessarily essential to this application.

[0093] The above are merely preferred embodiments of this application. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A self-learning method for the characteristic curve of a Venturi differential pressure sensor, characterized in that, include: Obtain vehicle operating conditions; When the vehicle operating conditions meet the preset operating conditions, the standard flow rate of the EGR valve is determined, the flow rate model of the EGR valve is built, the detection values ​​of the front pressure sensor and the rear pressure sensor of the EGR valve and the opening value of the EGR valve are obtained, and the third pressure difference value of the front and rear pressures of the EGR valve is determined based on the detection values. The standard flow rate is determined based on the flow rate model, the opening value and the third pressure difference value. Acquire a first differential pressure value detected by a Venturi differential pressure sensor and a second differential pressure value learned based on the first differential pressure value; The first flow rate of the EGR valve is determined based on the first differential pressure value, the second flow rate of the EGR valve is determined based on the second differential pressure value, and the first difference between the standard flow rate and the first flow rate, and the second difference between the standard flow rate and the second flow rate are determined. The characteristic curve of the Venturi differential pressure sensor is determined based on the first difference and the second difference.

2. The self-learning method for the characteristic curve of the Venturi differential pressure sensor as described in claim 1, characterized in that, The determination of the characteristic curve of the Venturi differential pressure sensor based on the first difference and the second difference includes: When the first difference is less than the second difference, the characteristic curve corresponding to the first pressure difference is determined to be the characteristic curve of the Venturi differential pressure sensor; When the first difference is greater than the second difference, the characteristic curve corresponding to the second pressure difference is determined to be the characteristic curve of the Venturi differential pressure sensor.

3. The self-learning method for the characteristic curve of the Venturi differential pressure sensor as described in claim 1, characterized in that, Also includes: Construct a Venturi pressure differential model; The standard pressure difference is determined based on the Venturi pressure difference model and the standard flow rate. A third difference is determined based on the standard pressure difference and the first pressure difference value, and a fourth difference is determined based on the standard pressure difference and the second pressure difference value; The characteristic curve of the Venturi differential pressure sensor is determined based on the third and fourth differences.

4. The self-learning method for the characteristic curve of the Venturi differential pressure sensor as described in claim 3, characterized in that, The determination of the characteristic curve of the Venturi differential pressure sensor based on the third difference and the fourth difference includes: When the third difference is greater than the fourth difference, the characteristic curve corresponding to the second differential pressure value is determined to be the characteristic curve of the Venturi differential pressure sensor. When the third difference is less than the fourth difference, the characteristic curve corresponding to the first differential pressure value is determined to be the characteristic curve of the Venturi differential pressure sensor.

5. The self-learning method for the characteristic curve of the Venturi differential pressure sensor as described in claim 1, characterized in that, Prior to obtaining vehicle operating conditions, the following is included: When determining that the vehicle is in a parked state, whether the pressure difference value 0 detected by the Venturi differential pressure sensor has drifted; When a drift occurs, proceed to the step of acquiring vehicle operating conditions.

6. The self-learning method for the characteristic curve of the Venturi differential pressure sensor as described in claim 5, characterized in that, Also includes: When the vehicle's operating condition does not meet the preset operating condition, the determination of the vehicle's operating condition is stopped, and after maintaining this for a preset time, the process returns to the step of determining whether the pressure difference value 0 detected by the Venturi differential pressure sensor has drifted when the vehicle is in a parked state.

7. A self-learning device for the characteristic curve of a Venturi differential pressure sensor, characterized in that, include: The first acquisition module is used to acquire vehicle operating conditions; The first analysis module is used to determine the standard flow rate of the EGR valve when the vehicle operating conditions meet the preset operating conditions, build the flow rate model of the EGR valve, obtain the detection values ​​of the front pressure sensor and the rear pressure sensor of the EGR valve and the opening value of the EGR valve, and determine the third pressure difference value of the front and rear pressures of the EGR valve based on the detection values, and determine the standard flow rate based on the flow rate model, the opening value and the third pressure difference value. The second acquisition module is used to acquire the first differential pressure value detected by the Venturi differential pressure sensor and the second differential pressure value learned by self-learning based on the first differential pressure value. The second analysis module determines the first flow rate of the EGR valve based on the first differential pressure value, determines the second flow rate of the EGR valve based on the second differential pressure value, and determines the first difference between the standard flow rate and the first flow rate, and the second difference between the standard flow rate and the second flow rate. The third analysis module determines the characteristic curve of the Venturi differential pressure sensor based on the first difference and the second difference.

8. An electronic device comprising a processor, a communication interface, a memory, and a communication bus, wherein, The processor, the communication interface, and the memory communicate with each other via the communication bus, characterized in that... The memory is used to store computer programs; The processor is configured to execute the self-learning method for the characteristic curve of the Venturi differential pressure sensor according to any one of claims 1-6 by running the computer program stored in the memory.

9. A computer-readable storage medium, characterized in that, The storage medium stores a computer program, wherein the computer program is configured to execute a self-learning method for the characteristic curve of the Venturi differential pressure sensor according to any one of claims 1-6 when running.

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