A flow calculation method, device and electronic equipment

Abstract

The embodiments of the present application provide a flow calculation method, device and electronic device, which relate to the field of flow calculation technology, including: obtaining multiple groups of measurement data; determining a target flow based on target measurement data and a reference throat size, and determining a reference flow based on reference measurement data; when it is determined that the flow deviation between the target flow and the reference flow exceeds a preset range, iteratively executing the following steps until the flow deviation is within the preset range, and obtaining a target offset factor corresponding to any preset operating condition: determining an offset factor based on the flow deviation, and correcting the reference throat size based on the offset factor; determining a corrected target flow based on the target measurement data and the corrected throat size, and calculating the flow deviation between the corrected target flow and the reference flow; determining a correction coefficient for correcting the throat size based on the target offset factor, and using the corrected throat size for flow calculation, thereby improving the accuracy of flow calculation.

Description

Technical Field

[0001] The present application relates to the technical field of flow calculation, and in particular to a flow calculation method, device and electronic equipment. Background Art

[0002] In recent years, the country has been increasingly strict in controlling various emission pollutants. Therefore, the EGR (Exhaust Gas Re-circulation) system is currently commonly used, which sends the exhaust gas after engine combustion back into the engine for reuse, thereby reducing the content of NOX (nitrides) and other emission pollutants in vehicle exhaust gas. How to accurately determine the EGR flow rate and air flow rate sent to the engine has become the top priority in improving the efficiency of exhaust gas utilization.

[0003] At present, most EGR systems use air flow meters to measure the air flow and EGR flow flowing into the engine cylinders. In the actual calculation process, the accuracy of the air flow meter's throat size data has a great influence on the accuracy of its calculation results. However, due to the poor consistency in the aperture processing process, it is difficult to ensure that the actual throat size of the air flow meter is completely consistent with the expected throat size. Therefore, there is a large deviation between the calculated air flow and EGR flow and their corresponding actual values. Summary of the invention

[0004] The present application provides a flow calculation method, device and electronic equipment for solving the problem of inaccurate calculated flow results caused by a large deviation between the actual throat size of an air flow meter and the expected throat size.

[0005] In a first aspect, an embodiment of the present application provides a flow calculation method, which is applied to an EGR system, wherein the EGR system comprises: a throttle, a first intake pipe, and an engine, wherein the throttle is arranged in the first intake pipe, and the first intake pipe is connected to a cylinder intake pipe of the engine through the air flow meter;

[0006] The above flow calculation method includes:

[0007] Allowing the engine to operate under any preset operating condition to obtain multiple sets of measurement data for flow calculation, wherein the multiple sets of measurement data include target measurement data corresponding to the throat area of ​​the air flow meter and at least one set of reference measurement data;

[0008] Determine a target flow rate based on the target measurement data and the reference throat size, determine a reference flow rate based on the reference measurement data, and calculate whether a flow rate deviation between the target flow rate and the reference flow rate exceeds a preset range;

[0009] When it is determined that the flow deviation exceeds the preset range, the following steps are iteratively performed until the flow deviation is within the preset range, and the target offset factor corresponding to any of the preset working conditions is obtained: an offset factor corresponding to the target flow is determined according to the flow deviation, and the reference throat size is corrected according to the offset factor; a corrected target flow is determined according to the target measurement data and the corrected throat size, and a flow deviation between the corrected target flow and the reference flow is calculated;

[0010] The correction coefficient is determined according to the corresponding target deviation factor under various preset working conditions, and the reference throat size is corrected based on the correction coefficient, and the flow rate is calculated using the corrected throat size.

[0011] The above-mentioned flow calculation method obtains multiple sets of measurement data when the engine is running under each preset working condition, determines the target flow corresponding to the throat area and at least one reference flow according to the obtained multiple sets of measurement data, and when the flow deviation between the target flow and the reference flow exceeds the limit, corrects the reference throat size according to the flow deviation, and determines the target flow again using the corrected throat size until the flow deviation between the target flow and the reference flow is within a preset range, and obtains the target offset factor corresponding to each preset working condition; determines the correction coefficient for correcting the throat size according to each target offset factor, and uses the corrected throat size for flow calculation, thereby improving the accuracy of the throat size, and further improving the accuracy of the flow calculation.

[0012] Further, the at least one set of reference measurement data includes: first reference measurement data corresponding to the throttle valve and second reference measurement data corresponding to the cylinder intake pipe of the engine;

[0013] Further, the above-mentioned determination of the reference flow rate based on the above-mentioned reference measurement data, and calculation of whether the flow rate deviation between the above-mentioned target flow rate and the reference flow rate exceeds a preset range, include:

[0014] Determine a first reference flow rate based on the first reference measurement data, and determine a second reference flow rate based on the second reference measurement data;

[0015] Calculate whether a first flow rate deviation between the target flow rate and the first reference flow rate exceeds a first preset range, and calculate whether a second flow rate deviation between the target flow rate and the second reference flow rate exceeds a second preset range.

[0016] Further, the above determination that the flow deviation exceeds a preset range includes:

[0017] Determining that the first flow deviation exceeds a first preset range; and / or

[0018] It is determined that the second flow rate deviation exceeds a second preset range.

[0019] Further, the offset factor corresponding to the target flow rate is determined according to the flow rate deviation based on the following formula:

[0020] Dofs=[Δm 0 ×fac+Δm 1 ×(1-fac)]×k 1 +Dofs_z 1

[0021] Where Dofs is the offset factor corresponding to the above target flow, Δm 0 is the first flow deviation, Δm 1 is the second flow deviation, fac is the weight coefficient corresponding to the above preset working condition, k 1 For the parameters with preset values, Dofs_z 1 is the offset factor of the previous iteration. When the above Dofs is the first iteration, the above Dofs_z 1 is 0; the weight coefficient represents the dependence of the target flow on the first reference flow and the second reference flow under the preset working condition.

[0022] Furthermore, before correcting the reference throat size based on the correction coefficient, the method further includes:

[0023] Comparing the correction coefficient with a preset correction threshold to determine whether the correction coefficient exceeds the correction threshold;

[0024] When it is determined that the correction coefficient does not exceed the correction threshold, the step of correcting the reference throat size based on the correction coefficient is performed.

[0025] In a second aspect, an embodiment of the present application provides a flow calculation device, which is applied to an EGR system, wherein the EGR system comprises: a throttle valve, a first intake pipe, and an engine, wherein the throttle valve is arranged in the first intake pipe, and the first intake pipe is connected to a cylinder intake pipe of the engine through the air flow meter;

[0026] The above-mentioned flow calculation device comprises:

[0027] a data acquisition module, used to acquire multiple sets of measurement data for flow calculation when the engine is running under any preset working condition, wherein the multiple sets of measurement data include target measurement data corresponding to the throat area of ​​the air flow meter and at least one set of reference measurement data;

[0028] a deviation calculation module, used to determine a target flow rate based on the target measurement data and a reference throat size, determine a reference flow rate based on the reference measurement data, and calculate whether a flow rate deviation between the target flow rate and the reference flow rate exceeds a preset range;

[0029] A determination module, for determining that when the flow deviation exceeds a preset range, iteratively executing the following steps until the flow deviation is within the preset range, and obtaining a target offset factor corresponding to any of the preset working conditions: determining an offset factor corresponding to the target flow according to the flow deviation, and correcting the reference throat size according to the offset factor; determining a corrected target flow according to the target measurement data and the corrected throat size, and calculating a flow deviation between the corrected target flow and the reference flow;

[0030] The flow calculation module is used to determine the correction coefficient according to the corresponding target offset factor under various preset working conditions, and to correct the reference throat size based on the correction coefficient, and to calculate the flow using the corrected throat size.

[0031] Further, the at least one set of reference measurement data includes: first reference measurement data corresponding to the throttle valve and second reference measurement data corresponding to the cylinder intake pipe of the engine;

[0032] The above deviation calculation module is specifically used for:

[0033] Determine a first reference flow rate based on the first reference measurement data, and determine a second reference flow rate based on the second reference measurement data;

[0034] Calculate whether a first flow rate deviation between the target flow rate and the first reference flow rate exceeds a first preset range, and calculate whether a second flow rate deviation between the target flow rate and the second reference flow rate exceeds a second preset range.

[0035] Furthermore, the determination module determines an offset factor corresponding to the target flow rate according to the flow rate deviation based on the following formula:

[0036] Dofs=[Δm 0 ×fac+Δm 1 ×(1-fac)]×k 1 +Dofs_z 1

[0037] Where Dofs is the offset factor corresponding to the above target flow, Δm 0 is the first flow deviation, Δm 1 is the second flow deviation, fac is the weight coefficient corresponding to the above preset working condition, k 1 For the parameters with preset values, Dofs_z 1is the offset factor of the previous iteration. When the above Dofs is the first iteration, the above Dofs_z 1 is 0; the weight coefficient represents the dependence of the target flow on the first reference flow and the second reference flow under the preset working condition.

[0038] In a third aspect, the present application provides an electronic device, including:

[0039] Memory, used to store computer programs;

[0040] The processor is used to execute the following steps when running the computer program stored in the above-mentioned memory:

[0041] Allowing the engine to operate under any preset operating condition to obtain multiple sets of measurement data for flow calculation, wherein the multiple sets of measurement data include target measurement data corresponding to the throat area of ​​the air flow meter and at least one set of reference measurement data;

[0042] Determine a target flow rate based on the target measurement data and the reference throat size, determine a reference flow rate based on the reference measurement data, and calculate whether a flow rate deviation between the target flow rate and the reference flow rate exceeds a preset range;

[0043] When it is determined that the flow deviation exceeds the preset range, the following steps are iteratively performed until the flow deviation is within the preset range, and the target offset factor corresponding to any of the preset working conditions is obtained: an offset factor corresponding to the target flow is determined according to the flow deviation, and the reference throat size is corrected according to the offset factor; a corrected target flow is determined according to the target measurement data and the corrected throat size, and a flow deviation between the corrected target flow and the reference flow is calculated;

[0044] The correction coefficient is determined according to the corresponding target deviation factor under various preset working conditions, and the reference throat size is corrected based on the correction coefficient, and the flow rate is calculated using the corrected throat size.

[0045] In a fourth aspect, the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the above-mentioned flow calculation method steps are implemented.

[0046] The fifth method, an embodiment of the present application provides a computer program product, including a computer program, which is stored in a computer-readable storage medium; when the processor of the memory access device reads the computer program from the computer-readable storage medium, the processor executes the computer program, so that the memory access device performs the above-mentioned traffic calculation method steps.

[0047] The various aspects of the second to fourth aspects and the technical effects that may be achieved by each aspect refer to the technical effects that can be achieved by the various possible schemes in the first aspect, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0049] Figure 1 A schematic diagram of the structure of an EGR system provided in an embodiment of the present application;

[0050] Figure 2 A flow chart of a flow calculation method provided in an embodiment of the present application;

[0051] Figure 3 A flow chart of the flow calculation process provided in the embodiment of the present application;

[0052] Figure 4 A schematic diagram of the structure of a flow calculation device provided in an embodiment of the present application;

[0053] Figure 5 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0054] In order to make the purpose, technical solution and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings. The application scenario described in the embodiment of the present application is to more clearly illustrate the technical solution of the embodiment of the present application, and does not constitute a limitation on the technical solution provided in the embodiment of the present application. It is known to those of ordinary skill in the art that with the emergence of new application scenarios, the technical solution provided in the embodiment of the present application is equally applicable to similar technical problems. Among them, in the description of the present application, unless otherwise specified, the meaning of "multiple" is two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist, for example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. A is connected to B, which can represent: A is directly connected to B and A is connected to B through C.

[0055] In addition, the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the attached claims. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present application.

[0056] The embodiments of the present application are described in detail below in conjunction with the accompanying drawings.

[0057] In recent years, the country has been increasingly strict in controlling various emission pollutants. Therefore, the EGR system is currently commonly used, which is to send the exhaust gas after engine combustion back into the engine for reuse, thereby reducing the content of emission pollutants such as NOX in vehicle exhaust gas. How to accurately determine the EGR flow and air flow sent to the engine has become the top priority in improving the efficiency of exhaust gas utilization.

[0058] At present, most EGR systems use air flow meters to measure the air flow and EGR flow flowing into the engine cylinder. The air flow meter has high transient air flow accuracy and is less affected by environmental factors, but it is more sensitive to its own processing accuracy. Therefore, in the actual calculation process, when using the air flow meter to calculate the flow, the accuracy of the throat size of the air flow meter used is required to be high, and the accuracy of the throat size data has a great impact on the accuracy of its calculation results. However, when the air flow meter is currently processed, the consistency of the aperture processing is poor, and it is difficult to ensure that the actual throat size is completely consistent with the expected throat size, which leads to inaccurate calculations of air flow and EGR flow, and there is a large deviation from the corresponding actual values.

[0059] In response to the above problems, an embodiment of the present application provides a flow calculation method, which determines a target flow and a reference flow based on the target measurement data corresponding to the throat area of ​​the air flow meter and at least one set of reference measurement data collected, and corrects the expected reference throat size based on the target flow and reference flow, thereby improving the data accuracy of the throat size and thereby improving the accuracy of the flow calculation.

[0060] The above flow calculation method of this application is applied to the EGR system. Figure 1 The structural diagram of the EGR system provided in the embodiment of the present application is as follows: Figure 1As shown, the EGR system includes: a throttle, a first intake pipe and an engine, the throttle is arranged in the first intake pipe, and the first intake pipe is connected to the cylinder intake pipe of the engine through an air flow meter (the part with a contraction structure between the first intake pipe and the cylinder intake pipe in the figure). During the use of the EGR system, after the air flows into the first intake pipe, the speed of the air flow is controlled by the throttle. At the same time, the first intake pipe also includes a gas inlet, as shown in the figure, the gas inlet is arranged on the first intake pipe, between the throttle and the air flow meter, and the gas can be flowed in through the gas inlet; at the same time, as shown in the figure, the size of the intake side of the cylinder intake pipe (the side close to the first intake pipe) is larger than the throat size of the air flow meter, and the exhaust gas in the EGR system can flow into the cylinder intake pipe through this part, and then flow into the cylinder.

[0061] In one possible implementation, the EGR system also includes a pressure measuring device, which is respectively installed on the inner side of the first intake duct in front of the throttle valve (position 0), the throat of the air flow meter (position 1), and a position close to the cylinder in the cylinder intake duct (position 2), and is used to measure the pressure at positions 0, 1, and 2 when the engine is running.

[0062] Figure 2 A flow chart of a flow calculation method provided in an embodiment of the present application; Figure 2 As shown, the embodiment of the present application provides a flow calculation method, which is applied to the above-mentioned EGR system. The method specifically includes the following steps:

[0063] Step 201, when the engine is operated under any preset working condition, a plurality of groups of measurement data for flow calculation are obtained, wherein the plurality of groups of measurement data include target measurement data corresponding to the throat area of ​​the air flow meter and at least one group of reference measurement data;

[0064] In a possible implementation manner, the at least one set of reference measurement data includes: first reference measurement data corresponding to the throttle valve and second reference measurement data corresponding to the cylinder intake pipe of the engine.

[0065] In a possible implementation, the target measurement data include but are not limited to: the temperature at position 0, the pressure at position 1 and position 0; the first reference parameter include but are not limited to: the temperature at position 0, the pressure at position 2 and position 0, the throttle opening (used to calculate the throttle flow area); the second reference parameter include but are not limited to: engine speed, engine displacement, temperature and pressure at position 2.

[0066] Step 202, determining a target flow rate based on the target measurement data and the reference throat size, determining a reference flow rate based on the reference measurement data, and calculating whether a flow rate deviation between the target flow rate and the reference flow rate exceeds a preset range;

[0067] The above-mentioned reference throat size is a standard throat size expected when manufacturing an air flow meter. In some optional embodiments, the throat size may be a throat diameter.

[0068] In a possible implementation, Figure 3 As shown, the above-mentioned determination of the reference flow rate based on the reference measurement data specifically includes: determining the first reference flow rate m based on the first reference measurement data 0 , and determine the second reference flow m based on the second reference measurement data 1 ;

[0069] Specifically, the first reference flow rate m is determined based on the first reference measurement data by the following formula: 0 :

[0070]

[0071] The second reference flow rate m is determined based on the second reference measurement data by the following formula 1 :

[0072]

[0073] The target flow rate m is determined based on the target measurement data and the reference throat size using the following formula 2 :

[0074]

[0075] Among them, k 0 , k 1 , k 2 Based on the speed and p 2 The parameters determined by the binary difference table, the data in the binary difference table can be obtained in advance through experimental calibration; d 0 d v d 1 They are the diameters before the throttle valve (i.e. Figure 1 diameter at the middle position 0), throttle opening equivalent diameter, throat diameter (i.e. Figure 1 The diameter at position 1 in the middle is a constant) and can be obtained from the system; A v , A 1 is the throttle flow area (based on d v Determine), position 1 throat area (based on d 1 OK); 0 、p 1 、p2 are the pressures at position 0, position 1 and position 2, respectively, and can be obtained by measurement; ρ 0 is the density at position 0, through p 0 , T 0 And the ideal gas state equation is obtained, specifically: Where M is the molar mass of air, which is a constant; T 2 , T 0 is the temperature at position 2 and position 0; V cyl is the engine displacement; n 1 is the engine speed, which can be obtained by measurement; R is the gas constant.

[0076] After obtaining the first reference flow m 0 , the second reference flow m 1 And the target flow m 2 Then, calculate the target flow m 2 With the first reference flow m 0 The first flow deviation Δm 0 , and the target flow m 2 With the second reference flow m 1 The second flow deviation Δm 1 .

[0077] Determine whether the first flow deviation exceeds a first preset range, and whether the second flow deviation exceeds a second preset range; when it is determined that the first flow deviation exceeds the first preset range, and / or when it is determined that the second flow deviation exceeds the second preset range, determine that the flow deviation exceeds the preset range.

[0078] It should be noted that the first preset range and the second preset range can be set by the user according to their own needs, and can be set to the same or different value ranges. In addition, the first flow deviation Δm 0 Can be m 2 -m 0 The value of can also be the absolute value of the difference. The first flow deviation Δm 1 Can be m 2 -m 1 The numerical value can also be the absolute value of the difference.

[0079] Step 203, when it is determined that the flow deviation exceeds the preset range, iteratively execute the following steps until the flow deviation is within the preset range, and obtain the target offset factor corresponding to any preset working condition: determine the offset factor corresponding to the target flow according to the flow deviation, and correct the reference throat size according to the offset factor; determine the corrected target flow according to the target measurement data and the corrected throat size, and calculate the flow deviation between the corrected target flow and the reference flow;

[0080] The target offset factor corresponding to any of the above preset working conditions is the offset factor determined in the last iteration process after the iteration is completed.

[0081] In some possible implementations, the offset factor corresponding to the target flow rate is determined based on the following formula:

[0082] Dofs=[Δm 0 ×fac+Δm 1 ×(1-fac)]×k 1 +Dofs_z 1

[0083] Wherein, Dofs is the offset factor corresponding to the target flow, Δm 0 is the first flow deviation, Δm 1 is the second flow deviation, fac is the weight coefficient corresponding to the preset working condition, k 1 is a parameter of preset value (i.e. step length, the specific value of which can be set by the user according to the requirements), Dofs_z 1 is the offset factor of the previous iteration. When the Dofs is the first iteration, the Dofs_z 1 is 0; the weight coefficient represents the dependence of the target flow on the first reference flow and the second reference flow under the preset operating conditions. The larger the weight coefficient, the greater the dependence of the target flow on the first reference flow, and the smaller the weight coefficient, the greater the dependence of the target flow on the second reference flow.

[0084] In a specific implementation, a corresponding weight coefficient can be set in advance for each preset working condition and a two-dimensional interpolation table can be formed. Each time a weight coefficient is obtained, the corresponding weight coefficient is queried from the two-dimensional difference table according to the current preset working condition.

[0085] After determining the offset factor Dofs, the reference throat size can be corrected according to the offset factor. The correction method can be to sum the reference throat size and the offset factor to obtain the corrected throat size. After determining the corrected throat size, the corrected target flow is determined according to the target measurement data and the corrected throat size, and the process of calculating the flow deviation between the corrected target flow and the reference flow is the same as the process of determining the target flow in step 203. For details, please refer to the relevant description of step 203, which will not be repeated here.

[0086] Step 204 , determining a correction coefficient according to target offset factors corresponding to various preset working conditions, and correcting the reference throat size based on the correction coefficient, and using the corrected throat size to calculate the flow rate.

[0087] In an optional embodiment, the above-mentioned multiple preset operating conditions can be freely set by the user. For example, the preset operating conditions include the operating conditions of the engine at different speeds and different loads. After obtaining the target offset factor corresponding to each preset operating condition, each target offset factor is averaged to obtain a correction coefficient, and the above-mentioned reference throat size is corrected based on the correction coefficient, such as summing the reference throat size and the correction coefficient to obtain the corrected reference throat size.

[0088] After obtaining the corrected reference throat size, the corrected reference size can be used to calculate the flow rate. In a possible implementation, the specific process of the flow rate calculation is the same as the above-mentioned target flow rate calculation process, which will not be repeated here.

[0089] In an optional embodiment, before correcting the reference throat size based on the correction coefficient in the above step 204, it is also necessary to compare the correction coefficient with a preset correction threshold to determine whether the correction coefficient exceeds the correction threshold; when it is determined that the correction coefficient does not exceed the correction threshold, it can be determined that the correction coefficient is correct, and the subsequent steps of correcting the reference throat size based on the correction coefficient can be continued; when it is determined that the correction coefficient exceeds the correction threshold, that is, the correction coefficient is out of limit, a fault reminder is sent to the user at this time, so that the user can determine that the correction coefficient is wrong according to the fault reminder, and conduct detailed production troubleshooting or replacement of EGR system components.

[0090] It should be noted that the above-mentioned correction threshold can be set and modified manually, and the present application does not limit its specific value. The above-mentioned method of sending a fault reminder to the user can be triggering an alarm, sending a fault message, etc., and the present application does not limit its specific method.

[0091] The above-mentioned flow calculation method obtains multiple sets of measurement data when the engine is running under each preset working condition, determines the target flow corresponding to the throat area and at least one reference flow according to the obtained multiple sets of measurement data, and when the flow deviation between the target flow and the reference flow exceeds the limit, corrects the reference throat size according to the flow deviation, and determines the target flow again using the corrected throat size until the flow deviation between the target flow and the reference flow is within a preset range, and obtains the target offset factor corresponding to each preset working condition; determines the correction coefficient for correcting the throat size according to each target offset factor, and uses the corrected throat size for flow calculation, thereby improving the accuracy of the throat size, and further improving the accuracy of the flow calculation.

[0092] Figure 3 The flow chart of the flow calculation process provided in the embodiment of the present application is as follows: Figure 3, the specific implementation process of the flow calculation method of the present application is described in detail. Preferably, the flow calculation method is applied to a relatively ideal test environment, that is, to ensure that various flow calculation deviations are not related to gas composition and air leakage in the intake pipe, but only to the manufacturing tolerance of key components:

[0093] Step 301, running the engine to a set operating condition;

[0094] The external switch is triggered to activate the test self-learning switch and control the engine to run to the set operating conditions.

[0095] Step 302, obtaining measurement data;

[0096] In implementation, an ECU (Electronic Control Unit) in the EGR system receives an activation instruction of a self-learning switch and obtains measurement data.

[0097] The above-mentioned measurement data include target measurement data corresponding to the throat area of ​​the air flow meter and at least one set of reference measurement data, and the above-mentioned at least one set of reference measurement data includes: first reference measurement data corresponding to the throttle valve and second reference measurement data corresponding to the cylinder intake pipe of the engine.

[0098] Step 303, calculating the target flow rate and the reference flow rate, and calculating the flow rate deviation between the target flow rate and the reference flow rate;

[0099] Specifically, a target flow rate is determined based on the target measurement data and a reference throat size, a first reference flow rate is determined based on the first reference measurement data, and a second reference flow rate is determined based on the second reference measurement data.

[0100] A first flow rate deviation between the target flow rate and the first reference flow rate, and a second flow rate deviation between the target flow rate and the second reference flow rate are calculated respectively.

[0101] The above calculation process is detailed in step 202 and will not be described again here.

[0102] Step 304, determine whether the deviation exceeds a preset range; if the result is yes, execute step 305, if the result is no, execute step 307;

[0103] In implementation, when it is determined that the first flow deviation exceeds the first preset range, and / or when it is determined that the second flow deviation exceeds the second preset range, it can be determined that the flow deviation exceeds the preset range.

[0104] Step 305, obtaining a weight coefficient, and calculating an offset factor according to the weight coefficient and the flow deviation;

[0105] Specifically, the above offset factor is determined based on the following formula:

[0106] Dofs=[Δm 0 ×fac+Δm 1 ×(1-fac)]×k 1 +Dofs_z 1

[0107] Where Dofs is the offset factor, Δm 0 is the first flow deviation, Δm 1 is the second flow deviation, fac is the weight coefficient corresponding to the current preset working condition, k 1 For the parameters with preset values, Dofs_z 1 is the offset factor of the previous iteration.

[0108] Step 306, correcting the reference throat diameter according to the offset factor, calculating the corrected target flow, and calculating the flow deviation between the corrected target flow and the reference flow; returning to step 304;

[0109] Step 307, recording the target offset factor;

[0110] It is determined that the deviation does not exceed the preset range, the iteration is determined to be finished, and the offset factor determined in the last iteration process is recorded as the target offset factor corresponding to the current preset working condition.

[0111] Step 308, determine whether all working conditions have been learned; if the result is yes, execute step 309, if the result is no, return to step 302;

[0112] Step 309, determining a correction coefficient according to the target offset factor of each working condition;

[0113] Specifically, after the target offset factors corresponding to all preset working conditions are calculated, the average value of the target offset factors is taken as the correction coefficient Dofs_Fin, and the pre-recorded target offset factors corresponding to the preset working conditions are cleared.

[0114] Step 310, determining whether the correction coefficient exceeds the correction threshold; if the result is yes, executing step 312, if the result is no, executing step 311;

[0115] The correction coefficient is compared with a preset correction threshold to determine whether the correction coefficient exceeds the correction threshold.

[0116] Step 311, recording the correction coefficient, and using the correction coefficient to correct the reference throat size;

[0117] When it is determined that the correction coefficient does not exceed the correction threshold, the correction coefficient can be determined to be correct, and the reference throat size Draw is corrected based on the correction coefficient Dofs_Fin: D_Fin=Draw+Dofs_Fin, and the flow calculation is performed using the corrected throat size D_Fin.

[0118] Step 312, reporting a fault, reminding the user to conduct a detailed production check or replace components.

[0119] Specifically, when it is determined that the correction coefficient exceeds the correction threshold, that is, the correction coefficient is out of limit, a fault reminder is sent to the user, so that the user can determine that the correction coefficient is wrong according to the fault reminder and perform detailed production inspection or replace EGR system components.

[0120] Based on the same application concept, the embodiment of the present application also provides a flow calculation device, which is applied to an exhaust gas recirculation EGR system. The above-mentioned EGR system includes: a throttle, a first intake pipe and an engine. The throttle is arranged in the first intake pipe, and the first intake pipe is connected to the cylinder intake pipe of the engine through the air flow meter; Figure 4 FIG. 1 is a schematic diagram of a flow calculation device in the present application, and the device includes:

[0121] A data acquisition module 401 is used to acquire multiple sets of measurement data for flow calculation when the engine is running under any preset working condition, wherein the multiple sets of measurement data include target measurement data corresponding to the throat area of ​​the air flow meter and at least one set of reference measurement data;

[0122] The deviation calculation module 402 is used to determine a target flow rate based on the target measurement data and a reference throat size, determine a reference flow rate based on the reference measurement data, and calculate whether a flow rate deviation between the target flow rate and the reference flow rate exceeds a preset range;

[0123] The determination module 403 is used to iteratively perform the following steps until the flow deviation is within the preset range when it is determined that the flow deviation exceeds the preset range, and obtain the target offset factor corresponding to any preset working condition: determine the offset factor corresponding to the target flow according to the flow deviation, and correct the reference throat size according to the offset factor; determine the corrected target flow according to the target measurement data and the corrected throat size, and calculate the flow deviation between the corrected target flow and the reference flow;

[0124] The flow calculation module 404 is used to determine a correction coefficient according to the corresponding target offset factor under various preset working conditions, and to correct the reference throat size based on the correction coefficient, and to perform flow calculation using the corrected throat size.

[0125] Further, the at least one set of reference measurement data includes: first reference measurement data corresponding to the throttle valve and second reference measurement data corresponding to a cylinder intake duct of the engine;

[0126] The above deviation calculation module 402 is specifically used for:

[0127] determining a first reference flow rate based on the first reference measurement data, and determining a second reference flow rate based on the second reference measurement data;

[0128] It is calculated whether a first flow rate deviation between the target flow rate and the first reference flow rate exceeds a first preset range, and whether a second flow rate deviation between the target flow rate and the second reference flow rate exceeds a second preset range.

[0129] Further, the determination module 403 determines that the flow deviation exceeds a preset range, specifically including:

[0130] Determining that the first flow deviation exceeds a first preset range; and / or

[0131] It is determined that the second flow deviation exceeds a second preset range.

[0132] Furthermore, the determination module 403 determines the offset factor corresponding to the target flow rate according to the flow rate deviation based on the following formula:

[0133] Dofs=[Δm 0 ×fac+Δm 1 ×(1-fac)]×k 1 +Dofs_z 1

[0134] Wherein, Dofs is the offset factor corresponding to the target flow, Δm 0 is the first flow deviation, Δm 1 is the second flow deviation, fac is the weight coefficient corresponding to the preset working condition, k 1 For the parameters with preset values, Dofs_z 1 is the offset factor of the previous iteration. When the Dofs is the first iteration, the Dofs_z 1 is 0; the weight coefficient represents the dependence of the target flow on the first reference flow and the second reference flow under the preset working condition.

[0135] Furthermore, before the flow calculation module 404 corrects the reference throat size based on the correction coefficient, it is also used to:

[0136] Comparing the correction coefficient with a preset correction threshold to determine whether the correction coefficient exceeds the correction threshold;

[0137] When it is determined that the correction coefficient does not exceed the correction threshold, the step of correcting the reference throat size based on the correction coefficient is performed.

[0138] Based on the same application concept, an electronic device is also provided in the embodiment of the present application, and the electronic device can realize the functions of the aforementioned flow calculation method and device, referring to Figure 5 , the electronic device comprises:

[0139] At least one processor 51, and a memory 52 connected to the at least one processor 51. The specific connection medium between the processor 51 and the memory 52 is not limited in the embodiment of the present application. Figure 5 In the example, the processor 51 and the memory 52 are connected via a bus 50. The bus 50 is Figure 5 The connection between other components is shown by bold lines, and the connection between other components is only for schematic illustration and is not intended to be limiting. The bus 50 can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 5 Only one thick line is used in the figure, but it does not mean that there is only one bus or one type of bus. Alternatively, the processor 51 can also be called a controller, and there is no limitation on the name.

[0140] In the embodiment of the present application, the memory 52 stores instructions that can be executed by at least one processor 51. The at least one processor 51 can execute the flow calculation method discussed above by executing the instructions stored in the memory 52. ​​The processor 51 can implement Figure 5 The functions of each module in the device shown.

[0141] Among them, the processor 51 is the control center of the device, and can use various interfaces and lines to connect the various parts of the entire control device. By running or executing instructions stored in the memory 52 and calling data stored in the memory 52, the various functions of the device and processing data, the device can be monitored as a whole.

[0142] In a possible design, the processor 51 may include one or more processing units, and the processor 51 may integrate an application processor and a modem processor, wherein the application processor mainly processes an operating system, a user interface, and application programs, and the modem processor mainly processes wireless communications. It is understandable that the modem processor may not be integrated into the processor 51. In some embodiments, the processor 51 and the memory 52 may be implemented on the same chip, and in some embodiments, they may also be implemented separately on separate chips.

[0143] The processor 51 can be a general-purpose processor, such as a central processing unit (CPU), a digital signal processor, an application-specific integrated circuit, a field programmable gate array or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component, and can implement or execute the various methods, steps and logic block diagrams disclosed in the embodiments of the present application. The general-purpose processor can be a microprocessor or any conventional processor, etc. The steps of the flow calculation method disclosed in the embodiments of the present application can be directly embodied as a hardware processor to be executed, or can be executed by a combination of hardware and software modules in the processor.

[0144] The memory 52 is a non-volatile computer-readable storage medium that can be used to store non-volatile software programs, non-volatile computer executable programs and modules. The memory 52 may include at least one type of storage medium, such as a flash memory, a hard disk, a multimedia card, a card-type memory, a random access memory (Random Access Memory, RAM), a static random access memory (Static Random Access Memory, SRAM), a programmable read-only memory (Programmable Read Only Memory, PROM), a read-only memory (Read Only Memory, ROM), an electrically erasable programmable read-only memory (Electrically Erasable Programmable Read-Only Memory, EEPROM), a magnetic memory, a disk, an optical disk, etc. The memory 52 is any other medium that can be used to carry or store a desired program code in the form of an instruction or data structure and can be accessed by a computer, but is not limited thereto. The memory 52 in the embodiment of the present application can also be a circuit or any other device that can realize a storage function, for storing program instructions and / or data.

[0145] By programming the processor 51, the code corresponding to the flow calculation method described in the above embodiment can be fixed into the chip, so that the chip can execute the code when running. Figure 4 The steps of the flow calculation method of the embodiment shown are as follows: How to design and program the processor 51 is a technique known to those skilled in the art and will not be described in detail here.

[0146] Based on the same application concept, an embodiment of the present application further provides a storage medium, which stores computer instructions. When the computer instructions are executed on a computer, the computer executes the flow calculation method discussed above.

[0147] In some possible implementations, various aspects of the flow calculation method provided in the present application may also be implemented in the form of a program product, which includes a program code. When the program product is run on a device, the program code is used to enable the control device to execute the steps of the flow calculation method according to various exemplary implementations of the present application described above in this specification.

[0148] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0149] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0150] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0151] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0152] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A flow calculation method, characterized in that: Applied to an exhaust gas recirculation (EGR) system, the EGR system comprises: a throttle, a first air intake pipe and an engine, the throttle is arranged in the first air intake pipe, and the first air intake pipe is connected to the cylinder air intake pipe of the engine through an air flow meter; The flow calculation method comprises: When the engine is operated under any preset working condition, a plurality of groups of measurement data for flow calculation are obtained, wherein the plurality of groups of measurement data include target measurement data corresponding to the throat area of ​​the air flow meter and at least one group of reference measurement data; Determine a target flow rate based on the target measurement data and a reference throat size, determine a reference flow rate based on the reference measurement data, and calculate whether a flow rate deviation between the target flow rate and the reference flow rate exceeds a preset range; When it is determined that the flow deviation exceeds the preset range, the following steps are iteratively performed until the flow deviation is within the preset range, and the iteration is terminated, and the offset factor corresponding to the target flow determined in the last iteration process is used as the target offset factor corresponding to any preset working condition: the offset factor corresponding to the target flow is determined according to the flow deviation, and the reference throat size is corrected according to the offset factor; the corrected target flow is determined according to the target measurement data and the corrected throat size, and the flow deviation between the corrected target flow and the reference flow is calculated; A correction coefficient is determined according to target deviation factors corresponding to various preset working conditions, and the reference throat size is corrected based on the correction coefficient, and the flow rate is calculated using the corrected throat size.

2. The method according to claim 1, characterized in that The at least one set of reference measurement data comprises: first reference measurement data corresponding to the throttle valve and second reference measurement data corresponding to a cylinder intake duct of the engine; Determining a reference flow rate based on the reference measurement data, and calculating whether a flow rate deviation between the target flow rate and the reference flow rate exceeds a preset range, including: determining a first reference flow rate based on the first reference measurement data, and determining a second reference flow rate based on the second reference measurement data; It is calculated whether a first flow rate deviation between the target flow rate and the first reference flow rate exceeds a first preset range, and whether a second flow rate deviation between the target flow rate and the second reference flow rate exceeds a second preset range.

3. The method according to claim 2, characterized in that Determining that the flow deviation exceeds a preset range includes: Determining that the first flow deviation exceeds a first preset range; and / or It is determined that the second flow deviation exceeds a second preset range.

4. The method according to claim 2 or 3, characterized in that: The offset factor corresponding to the target flow rate is determined according to the flow rate deviation based on the following formula: Dofs=[Δm0×fac+Δm1×(1-fac)]×k1+Dofs_z1 Among them, Dofs is the offset factor corresponding to the target flow, Δm0 is the first flow deviation, Δm1 is the second flow deviation, fac is the weight coefficient corresponding to the preset operating condition, k1 is a parameter of a preset value, Dofs_z1 is the offset factor of the previous iteration, and when the Dofs is the first iteration, the Dofs_z1 is 0; the weight coefficient characterizes the dependence of the target flow on the first reference flow and the second reference flow under the preset operating condition.

5. The method according to any one of claims 1 to 3, characterized in that: Before correcting the reference throat size based on the correction coefficient, the method further includes: Comparing the correction coefficient with a preset correction threshold to determine whether the correction coefficient exceeds the correction threshold; When it is determined that the correction coefficient does not exceed the correction threshold, the step of correcting the reference throat size based on the correction coefficient is performed.

6. A flow calculation device, characterized in that: Applied to an exhaust gas recirculation (EGR) system, the EGR system comprises: a throttle, a first air intake pipe and an engine, the throttle is arranged in the first air intake pipe, and the first air intake pipe is connected to the cylinder air intake pipe of the engine through an air flow meter; The flow calculation device comprises: a data acquisition module, configured to acquire, when the engine is running under any preset operating condition, a plurality of sets of measurement data for flow calculation, wherein the plurality of sets of measurement data include target measurement data corresponding to the throat area of ​​the air flow meter and at least one set of reference measurement data; a deviation calculation module, used to determine a target flow rate based on the target measurement data and a reference throat size, determine a reference flow rate based on the reference measurement data, and calculate whether a flow rate deviation between the target flow rate and the reference flow rate exceeds a preset range; A determination module, for determining that when the flow deviation exceeds a preset range, iteratively executing the following steps until the flow deviation is within the preset range, and terminating the iteration, and using the offset factor corresponding to the target flow determined in the last iteration as the target offset factor corresponding to any preset working condition: determining the offset factor corresponding to the target flow according to the flow deviation, and correcting the reference throat size according to the offset factor; determining a corrected target flow according to the target measurement data and the corrected throat size, and calculating the flow deviation between the corrected target flow and the reference flow; The flow calculation module is used to determine the correction coefficient according to the corresponding target offset factor under various preset working conditions, and to correct the reference throat size based on the correction coefficient, and to perform flow calculation using the corrected throat size.

7. The device according to claim 6, characterized in that The at least one set of reference measurement data comprises: first reference measurement data corresponding to the throttle valve and second reference measurement data corresponding to a cylinder intake duct of the engine; The deviation calculation module is specifically used for: determining a first reference flow rate based on the first reference measurement data, and determining a second reference flow rate based on the second reference measurement data; It is calculated whether a first flow rate deviation between the target flow rate and the first reference flow rate exceeds a first preset range, and whether a second flow rate deviation between the target flow rate and the second reference flow rate exceeds a second preset range.

8. The device according to claim 7, characterized in that The determination module determines an offset factor corresponding to the target flow rate according to the flow rate deviation based on the following formula: Dofs=[Δm0×fac+Δm1×(1-fac)]×k1+Dofs_z1 Among them, Dofs is the offset factor corresponding to the target flow, Δm0 is the first flow deviation, Δm1 is the second flow deviation, fac is the weight coefficient corresponding to the preset operating condition, k1 is a parameter of a preset value, Dofs_z1 is the offset factor of the previous iteration, and when the Dofs is the first iteration, the Dofs_z1 is 0; the weight coefficient characterizes the dependence of the target flow on the first reference flow and the second reference flow under the preset operating condition.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 5 are implemented.

10. A computer-readable storage medium having computer program instructions stored thereon, characterized in that: When the computer program instructions are executed by a processor, the steps of the method according to any one of claims 1 to 5 are implemented.

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