Exhaust gas recirculation control method, device, computer equipment and storage medium

Abstract

The present application relates to an exhaust gas recirculation control method, device, computer equipment, storage medium and computer program product. The method comprises: obtaining engine parameters and environmental parameters; determining a high-pressure flow demand value and a low-pressure flow demand value according to the engine parameters and environmental parameters; obtaining a high-pressure valve opening adjustment value according to the high-pressure flow demand value through proportional integral differential control; determining a high-pressure valve opening according to the high-pressure valve demand opening and the high-pressure valve opening adjustment value; obtaining a low-pressure valve opening adjustment value according to the low-pressure flow demand value through proportional integral differential control; determining a low-pressure valve opening according to the low-pressure valve demand opening and the low-pressure valve opening adjustment value; setting the high-pressure valve to the high-pressure valve opening and the low-pressure valve opening to perform exhaust gas recirculation control. The use of the present method can ensure that emissions are reduced while having good fuel utilization.

Description

Technical Field

[0001] The present application relates to the field of engine control technology, and in particular to an exhaust gas recirculation control method, device, computer equipment, storage medium and computer program product. Background Art

[0002] Exhaust Gas Recirculation (EGR) technology, as a kind of intake and exhaust process control and combustion process control technology, is recognized as an effective measure to reduce diesel engine nitrogen oxide emissions.

[0003] At present, the exhaust gas recirculation control method often adopts a single high-pressure EGR or a single low-pressure EGR control strategy. The high-pressure EGR control strategy is to take out the exhaust gas from the upstream of the turbine and mix it with fresh air downstream of the intercooler, which can reduce the engine pumping loss and improve fuel utilization. However, due to the limitations of supercharger matching and in-cylinder combustion, the high-pressure EGR control strategy is usually difficult to achieve a large EGR rate and may cause particulate matter emissions and worse fuel consumption. The low-pressure EGR control strategy is to take out the exhaust gas from the downstream of the turbine and mix it with fresh air upstream of the compressor, which can reduce exhaust emissions, but the fuel utilization is low. Therefore, reducing emissions while having good fuel utilization has become an urgent problem to be solved by the existing exhaust gas recirculation control method. Summary of the invention

[0004] Based on this, it is necessary to provide an exhaust gas recirculation control method, device, computer equipment, computer readable storage medium and computer program product to address the above technical problems, which can ensure low emissions while having good fuel efficiency.

[0005] In a first aspect, the present application provides an exhaust gas recirculation control method. The method comprises:

[0006] Obtain engine parameters and environmental parameters;

[0007] Determine the high-pressure flow demand value and the low-pressure flow demand value according to the engine parameters and the environmental parameters;

[0008] According to the high-pressure flow demand value, the high-pressure valve opening adjustment value is obtained through proportional integral differential control; the high-pressure valve required opening is obtained by querying the high-pressure valve basic opening spectrum diagram; the high-pressure valve opening is determined according to the high-pressure valve required opening and the high-pressure valve opening adjustment value;

[0009] According to the low-pressure flow demand value, the low-pressure valve opening adjustment value is obtained through proportional integral differential control; the low-pressure valve required opening is obtained by querying the low-pressure valve basic opening spectrum diagram; the low-pressure valve opening is determined according to the low-pressure valve required opening and the low-pressure valve opening adjustment value;

[0010] The high-pressure valve is set to a high-pressure valve opening, and the low-pressure valve is set to a low-pressure valve opening for exhaust gas recirculation control.

[0011] In one embodiment, the engine parameters include engine speed, fuel injection amount, and coolant temperature;

[0012] According to the engine parameters and environmental parameters, determine the high-pressure flow demand value and the low-pressure flow demand value, including:

[0013] According to the engine speed and the injection amount, the total flow demand value is obtained;

[0014] According to the environmental parameters, the coolant temperature and the total flow demand value, the high-pressure flow demand value and the low-pressure flow demand value are determined.

[0015] In one embodiment, the environmental parameters include atmospheric temperature and atmospheric pressure; and the total flow demand value is obtained according to the engine speed and the fuel injection amount, including:

[0016] According to the engine speed and fuel injection amount, query the total flow demand map to obtain the basic value of the total flow demand;

[0017] According to the atmospheric temperature, atmospheric pressure and coolant temperature, the correction factor chart is consulted to obtain the atmospheric temperature correction factor, the atmospheric pressure correction factor and the coolant temperature correction factor respectively;

[0018] According to the atmospheric temperature correction factor, the atmospheric pressure correction factor and the coolant temperature correction factor, a comprehensive correction factor is obtained;

[0019] The total flow demand value is obtained based on the total flow demand basic value and the comprehensive correction coefficient.

[0020] In one embodiment, determining the high pressure flow requirement value and the low pressure flow requirement value according to the environmental parameters, the coolant temperature and the total flow requirement value includes:

[0021] According to the engine speed and the fuel injection amount, the operating condition table is queried to determine the target operating condition area; the target operating condition area includes multiple high-pressure flow ratios;

[0022] In the stored mapping relationship corresponding to each high-pressure flow ratio, the target specific fuel consumption corresponding to the total flow demand value is queried to obtain multiple target specific fuel consumptions; the stored mapping relationship is used to characterize the relationship between the specific fuel consumption and the total flow demand value;

[0023] The high-pressure flow rate ratio corresponding to the lowest specific fuel consumption among the multiple target specific fuel consumptions is taken as the optimal high-pressure flow rate ratio;

[0024] Determine the high-pressure flow demand value according to the total flow demand value and the optimal high-pressure flow ratio;

[0025] The difference between the total flow demand value and the high-pressure flow demand value is taken as the low-pressure flow demand value.

[0026] In one embodiment, according to the high-pressure flow demand value, the high-pressure valve opening adjustment value is obtained through proportional-integral-differential control, including:

[0027] Obtain high-pressure circuit parameters and Venturi tube pressure difference; high-pressure circuit parameters include high-pressure circuit temperature and high-pressure circuit pressure;

[0028] According to the engine parameters, query the working condition correction map to obtain the working condition correction coefficient;

[0029] Determine the high-pressure flow calculation value based on the high-pressure circuit parameters, the Venturi tube pressure difference and the operating correction factor;

[0030] The high-pressure flow calculation value and the high-pressure flow demand value are subjected to proportional-integral-differential control to obtain the high-pressure valve opening adjustment value.

[0031] In one embodiment, the engine parameters further include engine speed, engine intake pressure and engine intake temperature; the environmental parameters include atmospheric temperature;

[0032] According to the low-pressure flow demand value, the low-pressure valve opening adjustment value is obtained through proportional integral differential control, including:

[0033] Get low voltage circuit parameters;

[0034] According to the engine intake pressure and the engine speed, the charging efficiency map is queried to obtain the engine charging efficiency;

[0035] According to the engine intake pressure, the engine intake temperature, the engine speed, the engine charging efficiency and the engine theoretical charging amount, the actual engine charging amount is obtained;

[0036] Determine the low-pressure flow rate calculation value based on the actual engine charge, the high-pressure flow rate calculation value, the low-pressure circuit parameters and the atmospheric temperature;

[0037] The low-pressure flow calculation value and the low-pressure flow demand value are subjected to proportional-integral-differential control to obtain the low-pressure valve opening adjustment value.

[0038] In a second aspect, the present application also provides an exhaust gas recirculation control device. The device comprises:

[0039] An acquisition module, used to acquire engine parameters and environmental parameters;

[0040] A demand determination module, used to determine a high-pressure flow demand value and a low-pressure flow demand value according to engine parameters and environmental parameters;

[0041] The first opening determination module is used to obtain the high-pressure valve opening adjustment value through proportional integral differential control according to the high-pressure flow demand value; query the high-pressure valve basic opening map to obtain the high-pressure valve required opening; determine the high-pressure valve opening according to the high-pressure valve required opening and the high-pressure valve opening adjustment value;

[0042] The second opening determination module is used to obtain the low-pressure valve opening adjustment value through proportional integral differential control according to the low-pressure flow demand value; query the low-pressure valve basic opening spectrum diagram to obtain the low-pressure valve required opening; determine the low-pressure valve opening according to the low-pressure valve required opening and the low-pressure valve opening adjustment value;

[0043] The control module is used to set the high-pressure valve to a high-pressure valve opening and the low-pressure valve to a low-pressure valve opening for exhaust gas recirculation control.

[0044] In a third aspect, the present application further provides a computer device. The computer device includes a memory and a processor, the memory stores a computer program, and the processor implements the following steps when executing the computer program:

[0045] Obtain engine parameters and environmental parameters;

[0046] Determine the high-pressure flow demand value and the low-pressure flow demand value according to the engine parameters and the environmental parameters;

[0047] According to the high-pressure flow demand value, the high-pressure valve opening adjustment value is obtained through proportional integral differential control; the high-pressure valve required opening is obtained by querying the high-pressure valve basic opening spectrum diagram; the high-pressure valve opening is determined according to the high-pressure valve required opening and the high-pressure valve opening adjustment value;

[0048] According to the low-pressure flow demand value, the low-pressure valve opening adjustment value is obtained through proportional integral differential control; the low-pressure valve required opening is obtained by querying the low-pressure valve basic opening spectrum diagram; the low-pressure valve opening is determined according to the low-pressure valve required opening and the low-pressure valve opening adjustment value;

[0049] The high-pressure valve is set to a high-pressure valve opening, and the low-pressure valve is set to a low-pressure valve opening for exhaust gas recirculation control.

[0050] In a fourth aspect, the present application further provides a computer-readable storage medium. The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the following steps are implemented:

[0051] Obtain engine parameters and environmental parameters;

[0052] Determine the high-pressure flow demand value and the low-pressure flow demand value according to the engine parameters and the environmental parameters;

[0053] According to the high-pressure flow demand value, the high-pressure valve opening adjustment value is obtained through proportional integral differential control; the high-pressure valve required opening is obtained by querying the high-pressure valve basic opening spectrum diagram; the high-pressure valve opening is determined according to the high-pressure valve required opening and the high-pressure valve opening adjustment value;

[0054] According to the low-pressure flow demand value, the low-pressure valve opening adjustment value is obtained through proportional integral differential control; the low-pressure valve required opening is obtained by querying the low-pressure valve basic opening spectrum diagram; the low-pressure valve opening is determined according to the low-pressure valve required opening and the low-pressure valve opening adjustment value;

[0055] The high-pressure valve is set to a high-pressure valve opening, and the low-pressure valve is set to a low-pressure valve opening for exhaust gas recirculation control.

[0056] In a fifth aspect, the present application further provides a computer program product. The computer program product includes a computer program, and when the computer program is executed by a processor, the following steps are implemented:

[0057] Obtain engine parameters and environmental parameters;

[0058] Determine the high-pressure flow demand value and the low-pressure flow demand value according to the engine parameters and the environmental parameters;

[0059] According to the high-pressure flow demand value, the high-pressure valve opening adjustment value is obtained through proportional integral differential control; the high-pressure valve required opening is obtained by querying the high-pressure valve basic opening spectrum diagram; the high-pressure valve opening is determined according to the high-pressure valve required opening and the high-pressure valve opening adjustment value;

[0060] According to the low-pressure flow demand value, the low-pressure valve opening adjustment value is obtained through proportional integral differential control; the low-pressure valve required opening is obtained by querying the low-pressure valve basic opening spectrum diagram; the low-pressure valve opening is determined according to the low-pressure valve required opening and the low-pressure valve opening adjustment value;

[0061] The high-pressure valve is set to a high-pressure valve opening, and the low-pressure valve is set to a low-pressure valve opening for exhaust gas recirculation control.

[0062] The above-mentioned exhaust gas recirculation control method, device, computer equipment, storage medium and computer program product determine the high-pressure flow demand value and the low-pressure flow demand value by obtaining the engine parameters and environmental parameters, and obtain the high-pressure valve opening adjustment value and the low-pressure valve opening adjustment value respectively according to the high-pressure flow demand value and the low-pressure flow demand value through proportional integral differential control; determine the high-pressure valve opening according to the high-pressure valve demand opening and the high-pressure valve opening adjustment value; determine the low-pressure valve opening according to the low-pressure valve demand opening and the low-pressure valve opening adjustment value, set the high-pressure valve to the high-pressure valve opening, and set the low-pressure valve to the low-pressure valve opening, for exhaust gas recirculation control. The above scheme determines the high-pressure and low-pressure flow demand values ​​based on engine parameters and environmental parameters, and then determines the method of determining the opening of the high-pressure valve and the low-pressure valve. This is beneficial to determining different high-pressure valve and low-pressure valve openings under different engine parameters and environmental parameters, which is beneficial to improving the control efficiency of exhaust gas recirculation; through proportional integral differential control, the high-pressure valve and low-pressure valve opening adjustment values ​​are determined, and then the high-pressure valve and low-pressure valve openings are determined in combination with the high-pressure and low-pressure flow demand values. The exhaust gas recirculation control is performed by the joint work of the high-pressure valve and the low-pressure valve, which is beneficial to reducing emissions while having good fuel utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 is an application environment diagram of an exhaust gas recirculation control method in one embodiment;

[0064] Figure 2 is a schematic flow chart of an exhaust gas recirculation control method in one embodiment;

[0065] Figure 3 A schematic diagram of a process for obtaining a total flow demand value in one embodiment;

[0066] Figure 4 is a schematic diagram of a working condition table in one embodiment;

[0067] Figure 5 is a schematic diagram of an existing mapping relationship in an embodiment;

[0068] Figure 6 A schematic diagram of a process for obtaining a high-pressure flow demand value and a low-pressure flow demand value in an embodiment;

[0069] Figure 7 A schematic diagram of a process for obtaining a high-pressure valve opening adjustment value in an embodiment;

[0070] Figure 8 A schematic diagram of a process for obtaining a low-pressure valve opening adjustment value in one embodiment;

[0071] Fig. 9 is a schematic diagram of the structure of an exhaust gas recirculation control system in one embodiment;

[0072] Fig.10 is a structural block diagram of an exhaust gas recirculation control device in one embodiment;

[0073] Fig.11 FIG. 4 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0074] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0075] The exhaust gas recirculation control method provided in the embodiment of the present application can be applied to Figure 1 In the application environment shown. Among them, the controller 102 communicates with the engine 104 through the network. The controller 102 obtains engine parameters and environmental parameters; determines the high-pressure flow demand value and the low-pressure flow demand value according to the engine parameters and environmental parameters; obtains the high-pressure valve opening adjustment value through proportional integral differential control according to the high-pressure flow demand value; obtains the high-pressure valve demand opening by querying in the high-pressure valve basic opening map; determines the high-pressure valve opening according to the high-pressure valve demand opening and the high-pressure valve opening adjustment value; obtains the low-pressure valve opening adjustment value through proportional integral differential control according to the low-pressure flow demand value; obtains the low-pressure valve demand opening by querying in the low-pressure valve basic opening map; determines the low-pressure valve opening according to the low-pressure valve demand opening and the low-pressure valve opening adjustment value; sets the high-pressure valve to the high-pressure valve opening, and sets the low-pressure valve to the low-pressure valve opening for exhaust gas recirculation control. The controller 102 may be a vehicle electronic control unit (ECU), or various personal computers, laptops, smart phones, tablet computers, IoT devices, and portable wearable devices. IoT devices may be smart speakers, smart TVs, smart air conditioners, smart vehicle-mounted devices, etc. Portable wearable devices may be smart watches, smart bracelets, head-mounted devices, etc.

[0076] In one embodiment, Figure 2 As shown, an exhaust gas recirculation control method is provided, which is applied to Figure 1 The controller 102 in the example is used as an example to illustrate, and the following steps are included:

[0077] S201, acquiring engine parameters and environmental parameters.

[0078] The engine parameters refer to various parameters related to the engine, including engine speed, fuel injection amount, etc. The environmental parameters refer to various parameters related to the environment, including atmospheric temperature, atmospheric pressure, etc. The controller obtains the engine parameters and environmental parameters.

[0079] S202, determining a high-pressure flow demand value and a low-pressure flow demand value according to engine parameters and environmental parameters.

[0080] Among them, the exhaust gas recirculation control method is applied to the exhaust gas recirculation control system. The exhaust gas recirculation control includes a high-pressure circuit and a low-pressure circuit. The exhaust gas output from the engine can be recirculated into the engine through the high-pressure circuit, and can also be recirculated into the engine from the low-pressure circuit. The high-pressure flow demand value refers to the theoretical demand value of the exhaust gas flow in the high-pressure circuit. The low-pressure flow demand value refers to the theoretical demand value of the exhaust gas flow in the low-pressure circuit. The engine parameters and environmental parameters determine the operating conditions of the engine. Under different operating conditions, there are different high-pressure flow demand values ​​and low-pressure flow demand values. The controller determines the high-pressure flow demand value and the low-pressure flow demand value based on the engine parameters and environmental parameters.

[0081] S203, according to the high-pressure flow demand value, obtain the high-pressure valve opening adjustment value through proportional integral differential control; query the high-pressure valve basic opening spectrum diagram to obtain the high-pressure valve demand opening; determine the high-pressure valve opening according to the high-pressure valve demand opening and the high-pressure valve opening adjustment value.

[0082] Among them, the high-pressure valve refers to the control valve used to control the exhaust gas flow in the high-pressure circuit of the exhaust gas recirculation system. Proportional integral differential control is a method of controlling the controlled object by forming a control deviation based on a given value and an actual output value, and forming a control quantity by linearly combining the deviation in proportion, integral and differential. The controller obtains the high-pressure valve opening adjustment value through proportional integral differential control according to the high-pressure flow demand value. The high-pressure valve opening adjustment value is used to adjust the opening of the high-pressure valve.

[0083] The high-pressure valve basic opening map is used to characterize the mapping relationship between the engine parameters and the high-pressure valve opening basic value. The controller searches the high-pressure valve basic opening map for the target high-pressure valve opening basic value corresponding to the engine parameters. The target high-pressure valve opening basic value is used as the high-pressure valve required opening.

[0084] The controller uses the sum of the high-pressure valve opening requirement and the high-pressure valve opening adjustment value as the high-pressure valve opening. The high-pressure valve opening is used to indicate the angle at which the high-pressure valve is opened.

[0085] S204, according to the low-pressure flow demand value, obtain the low-pressure valve opening adjustment value through proportional integral differential control; query the low-pressure valve basic opening spectrum diagram to obtain the low-pressure valve demand opening; determine the low-pressure valve opening according to the low-pressure valve demand opening and the low-pressure valve opening adjustment value.

[0086] The low-pressure valve refers to the control valve used to control the exhaust gas flow in the low-pressure circuit of the exhaust gas recirculation system. The controller obtains the low-pressure valve opening adjustment value through proportional integral differential control according to the low-pressure flow demand value. The low-pressure valve opening adjustment value is used to adjust the opening of the low-pressure valve.

[0087] The low-pressure valve basic opening map is used to characterize the mapping relationship between the engine parameters and the low-pressure valve opening basic value. The controller searches the low-pressure valve basic opening map for the target low-pressure valve opening basic value corresponding to the engine parameters. The target low-pressure valve opening basic value is used as the low-pressure valve required opening.

[0088] The controller uses the sum of the low-pressure valve required opening and the low-pressure valve opening adjustment value as the low-pressure valve opening. The low-pressure valve opening is used to indicate the angle at which the low-pressure valve is opened.

[0089] S205, setting the high-pressure valve to a high-pressure valve opening, and setting the low-pressure valve to a low-pressure valve opening, for exhaust gas recirculation control.

[0090] Among them, the controller sets the high-pressure valve to the high-pressure valve opening and the low-pressure valve to the low-pressure valve opening, so that under the corresponding motion conditions, the high-pressure valve opens the corresponding high-pressure valve opening, and the exhaust gas enters the high-pressure circuit through the high-pressure valve and recirculates into the engine through the high-pressure circuit. Similarly, the low-pressure valve opens the corresponding low-pressure valve opening, and the exhaust gas enters the low-pressure circuit through the low-pressure valve and recirculates into the engine through the low-pressure circuit, thereby realizing exhaust gas recirculation control.

[0091] In the above exhaust gas recirculation control method, the high-pressure flow demand value and the low-pressure flow demand value are determined by obtaining the engine parameters and environmental parameters, and the high-pressure valve opening adjustment value and the low-pressure valve opening adjustment value are respectively obtained through proportional integral differential control based on the high-pressure flow demand value and the low-pressure flow demand value; the high-pressure valve opening is determined based on the high-pressure valve demand opening and the high-pressure valve opening adjustment value; the low-pressure valve opening is determined based on the low-pressure valve demand opening and the low-pressure valve opening adjustment value, the high-pressure valve is set to the high-pressure valve opening, and the low-pressure valve is set to the low-pressure valve opening, for exhaust gas recirculation control. The above scheme determines the high-pressure and low-pressure flow demand values ​​based on engine parameters and environmental parameters, and then determines the method of determining the opening of the high-pressure valve and the low-pressure valve. This is beneficial to determining different high-pressure valve and low-pressure valve openings under different engine parameters and environmental parameters, which is beneficial to improving the control efficiency of exhaust gas recirculation; through proportional integral differential control, the high-pressure valve and low-pressure valve opening adjustment values ​​are determined, and then the high-pressure valve and low-pressure valve openings are determined in combination with the high-pressure and low-pressure flow demand values. The exhaust gas recirculation control is performed by the joint work of the high-pressure valve and the low-pressure valve, which is beneficial to reducing emissions while having good fuel utilization.

[0092] In one embodiment, the engine parameters include engine speed, fuel injection amount and coolant temperature; the high-pressure flow demand value and the low-pressure flow demand value are determined according to the engine parameters and environmental parameters, including: obtaining the total flow demand value according to the engine speed and fuel injection amount; determining the high-pressure flow demand value and the low-pressure flow demand value according to the environmental parameters, coolant temperature and the total flow demand value.

[0093] The total flow demand value refers to the total flow value of exhaust gas in the exhaust gas recirculation system. The controller determines the total flow demand value under the corresponding operating conditions according to the engine speed and the injection amount. The total flow demand value includes the high-pressure flow demand value and the low-pressure flow demand value. The controller determines the high-pressure flow demand value and the low-pressure flow demand value according to the environmental parameters, the coolant temperature and the total flow demand value.

[0094] In this embodiment, the total flow demand value under the corresponding motion condition is obtained by the engine speed and the injection amount, and the high-pressure and low-pressure flow demand values ​​are determined in combination with the environmental parameters and the coolant temperature. Under different motion conditions, the corresponding high-pressure flow demand value and low-pressure flow demand value are obtained based on different environmental parameters and coolant temperatures, which is conducive to the exhaust gas recirculation control of the high-pressure valve and the low-pressure valve working together, which is conducive to reducing emissions while having good fuel utilization.

[0095] In one embodiment, the environmental parameters include atmospheric temperature and atmospheric pressure; a total flow demand value is obtained based on the engine speed and the fuel injection amount, including: querying the total flow demand spectrum diagram based on the engine speed and the fuel injection amount to obtain a total flow demand basic value; querying the correction coefficient diagram based on the atmospheric temperature, atmospheric pressure and coolant temperature to obtain the atmospheric temperature correction coefficient, the atmospheric pressure correction coefficient and the coolant temperature correction coefficient respectively; obtaining a comprehensive correction coefficient based on the atmospheric temperature correction coefficient, the atmospheric pressure correction coefficient and the coolant temperature correction coefficient; obtaining the total flow demand value based on the total flow demand basic value and the comprehensive correction coefficient.

[0096] Among them, the total flow demand spectrum is used to characterize the mapping relationship between the engine speed, the injection amount and the total flow demand basic value.

[0097] The controller finds the total flow demand basic value corresponding to the engine speed and injection amount from the total flow demand map.

[0098] The correction coefficient chart is used to represent the mapping relationship between various engine parameters, environmental parameters and corresponding correction coefficients.

[0099] The controller queries the atmospheric temperature correction coefficient corresponding to the atmospheric temperature, the atmospheric pressure correction coefficient corresponding to the atmospheric pressure, and the coolant temperature correction coefficient corresponding to the coolant temperature from the correction coefficient chart.

[0100] The product of the atmospheric temperature correction factor, the atmospheric pressure correction factor and the coolant temperature correction factor is taken as the comprehensive correction factor.

[0101] The product of the total flow demand base value and the comprehensive correction coefficient is taken as the total flow demand value. Figure 3 Shown is a schematic diagram of the process of obtaining the total flow demand value.

[0102] In this embodiment, the basic value of the total flow demand under the corresponding operating conditions and the correction value of each parameter are queried respectively through the engine parameters and the environmental parameters, and the product of the basic value of the total flow demand and the correction value of each parameter is used as the total flow demand value. The corresponding total flow demand value can be obtained under different engine conditions and environmental conditions, which is conducive to timely updating the opening of the high-pressure valve and the low-pressure valve, and improving the control efficiency of the exhaust gas recirculation.

[0103] In one embodiment, a high-pressure flow demand value and a low-pressure flow demand value are determined according to environmental parameters, coolant temperature and a total flow demand value, including: according to the engine speed and the fuel injection amount, querying the operating condition table to determine the target operating condition area; the target operating condition area includes multiple high-pressure flow ratios; in the stored mapping relationship corresponding to each high-pressure flow ratio, querying the target specific fuel consumption corresponding to the total flow demand value to obtain multiple target specific fuel consumptions; the stored mapping relationship is used to characterize the relationship between the specific fuel consumption and the total flow demand value; the high-pressure flow ratio corresponding to the lowest specific fuel consumption among the multiple target specific fuel consumptions is used as the optimal high-pressure flow ratio; the high-pressure flow demand value is determined according to the total flow demand value and the optimal high-pressure flow ratio; the difference between the total flow demand value and the high-pressure flow demand value is used as the low-pressure flow demand value.

[0104] The operating condition table is used to characterize the mapping relationship between engine speed, fuel injection amount and operating condition area. The operating condition table includes multiple operating condition areas, and each engine speed and fuel injection amount corresponds to its own operating condition area. Figure 4 The figure shows a schematic diagram of the operating condition table. In the figure, the horizontal axis represents the engine speed, the vertical axis represents the injection amount, and each grid represents a working condition area.

[0105] The controller searches the operating condition table for the target operating condition area corresponding to the engine speed and the injection amount. The target operating condition area includes multiple high-pressure flow ratios, each of which corresponds to its own stored mapping relationship, which is used to characterize the relationship between specific fuel consumption and the total flow demand value. Figure 5 Shown is a schematic diagram of the existing mapping relationship. In the figure, the horizontal axis represents the total flow demand value, the vertical axis represents the specific fuel consumption, α1 to α4 represent four high-pressure flow ratios, and the curves corresponding to α1 to α4 represent the existing mapping relationships corresponding to each high-pressure flow ratio.

[0106] The controller queries the target specific fuel consumption corresponding to the total flow demand value from the stored mapping relationship corresponding to each high-pressure flow ratio, and obtains multiple target specific fuel consumptions. The high-pressure flow ratio corresponding to the lowest specific fuel consumption among the multiple target specific fuel consumptions is taken as the optimal high-pressure flow ratio. The product of the total flow demand value and the optimal high-pressure flow ratio is taken as the high-pressure flow demand value, and the difference between the total flow demand value and the high-pressure flow demand value is taken as the low-pressure flow demand value. Figure 6 Shown is a schematic diagram of the process of obtaining high-pressure flow demand values ​​and low-pressure flow demand values.

[0107] In this embodiment, by determining the target operating area and taking the lowest specific fuel consumption as the goal, the optimal high-pressure flow ratio is obtained, thereby determining the high-pressure flow demand value and the low-pressure flow demand value. Since the optimal high-pressure flow ratio is selected based on the lowest specific fuel consumption, the obtained high-pressure flow demand value and low-pressure flow demand value are beneficial to reducing fuel consumption and thus reducing emissions.

[0108] In one embodiment, according to the high-pressure flow demand value, a high-pressure valve opening adjustment value is obtained through proportional-integral-differential control, including: obtaining high-pressure circuit parameters and Venturi tube pressure difference; the high-pressure circuit parameters include high-pressure circuit temperature and high-pressure circuit pressure; according to the engine parameters, querying the operating condition correction pulse spectrum to obtain the operating condition correction coefficient; according to the high-pressure circuit parameters, the Venturi tube pressure difference and the operating condition correction coefficient, determining the high-pressure flow calculation value; performing proportional-integral-differential control on the high-pressure flow calculation value and the high-pressure flow demand value to obtain the high-pressure valve opening adjustment value.

[0109] Among them, temperature sensors, pressure sensors, venturi tube flowmeters and differential pressure sensors are deployed in the high-pressure circuit. The differential pressure sensor is deployed at the thinnest position in the venturi tube flowmeter.

[0110] The controller obtains the high-pressure circuit temperature collected by the temperature sensor in the high-pressure circuit, obtains the high-pressure circuit pressure collected by the pressure sensor in the high-pressure circuit, and the venturi tube pressure difference collected by the pressure difference sensor. Among them, the high-pressure circuit temperature is used to characterize the temperature in the high-pressure circuit. The high-pressure circuit pressure is used to characterize the pressure in the high-pressure circuit. The venturi tube pressure difference is used to characterize the pressure difference between the exhaust gas flowing through the venturi tube and the inside and outside of the venturi tube.

[0111] The operating condition correction map is used to characterize the mapping relationship between the engine parameters and the operating condition correction coefficient. The engine parameters may be the engine speed and the injection amount.

[0112] The controller finds the operating condition correction coefficient corresponding to the engine parameters from the operating condition correction map.

[0113] The controller brings the high-pressure circuit parameters, the venturi tube pressure difference and the working condition correction coefficient into the high-pressure flow calculation formula to obtain the high-pressure flow calculation value. The high-pressure flow calculation formula is:

[0114]

[0115] Among them, Q HP_cal It indicates the calculated value of high pressure flow, β indicates the structural constant of the Venturi tube, which is related to the structural size and flow characteristics of the Venturi tube, R indicates the gas constant, and K2 indicates the working condition correction coefficient. HP Indicates the high pressure circuit pressure, T HP represents the high-pressure circuit temperature, and Δp represents the Venturi tube pressure difference.

[0116] The controller performs proportional-integral-differential control on the high-pressure flow calculation value and the high-pressure flow demand value to obtain the high-pressure valve opening adjustment value.

[0117] like Figure 7 The figure shows a schematic diagram of the process of obtaining the high-pressure valve opening adjustment value. The high-pressure flow initial value is obtained based on the high-pressure circuit temperature, high-pressure circuit pressure, Venturi tube pressure difference and Venturi tube structure constant. The high-pressure flow initial value is multiplied by the working condition correction coefficient to obtain the high-pressure flow calculation value, and then the proportional integral differential control is performed in combination with the high-pressure flow demand value to obtain the high-pressure valve opening adjustment value.

[0118] In this embodiment, the high-pressure flow calculation value is obtained through the relevant parameters of the high-pressure circuit and the engine parameters, and then the proportional-integral-differential control is performed in combination with the high-pressure flow demand value to obtain the high-pressure valve opening adjustment value. The high-pressure valve opening adjustment value can be determined according to different high-pressure circuit working conditions and engine working conditions, which is conducive to improving the exhaust gas circulation control efficiency in the high-pressure circuit, and is conducive to achieving low emissions while having good fuel utilization.

[0119] In one embodiment, the engine parameters also include engine speed, engine intake pressure and engine intake temperature; the environmental parameters include atmospheric temperature; according to the low-pressure flow demand value, a low-pressure valve opening adjustment value is obtained through proportional integral differential control, including: obtaining low-pressure circuit parameters; according to the engine intake pressure and engine speed, querying the charging efficiency spectrum diagram to obtain the engine charging efficiency; according to the engine intake pressure, engine intake temperature, engine speed, engine charging efficiency and engine theoretical charging, obtaining the actual engine charging; according to the actual engine charging, the high-pressure flow calculated value, the low-pressure circuit parameters and the atmospheric temperature, determining the low-pressure flow calculated value; performing proportional integral differential control on the low-pressure flow calculated value and the low-pressure flow demand value to obtain the low-pressure valve opening adjustment value.

[0120] Among them, the exhaust gas circulation control system also includes an intake pressure sensor and an intake temperature sensor. The controller obtains the engine intake pressure collected by the intake pressure sensor and obtains the engine intake temperature collected by the intake temperature sensor. The engine intake pressure is used to characterize the engine intake pressure. The engine intake temperature is used to characterize the engine intake temperature.

[0121] The low-pressure circuit parameters include the low-pressure circuit mixed gas temperature and the low-pressure circuit exhaust gas temperature. The exhaust gas in the low-pressure circuit is recirculated into the engine as a mixed gas together with the fresh air. A low-pressure EGR temperature sensor for collecting the low-pressure circuit mixed gas temperature and a mixed gas temperature sensor for collecting the mixed gas temperature are deployed in the low-pressure circuit. The low-pressure circuit mixed gas temperature is used to characterize the temperature of the mixed gas. The low-pressure circuit exhaust gas temperature is used to characterize the temperature of the exhaust gas in the low-pressure circuit.

[0122] The charging efficiency map is used to characterize the mapping relationship between the engine intake pressure, the engine speed and the engine charging efficiency. The controller queries the engine charging efficiency corresponding to the engine intake pressure and the engine speed from the charging efficiency map.

[0123] The controller takes the engine intake pressure, engine intake temperature, engine speed, engine charging efficiency and engine theoretical charge into the actual charge calculation formula to obtain the actual engine charge. The actual engine charge is used to characterize the actual gas capacity in the engine. The theoretical engine charge is used to characterize the theoretical gas capacity in the engine. The actual charge calculation formula is:

[0124]

[0125] Among them, Q represents the actual charge of the engine, const represents the theoretical charge of the engine, N represents the engine speed, R represents the gas constant, V represents the engine displacement, ε represents the engine charging efficiency, P int Indicates the engine intake pressure, T int Indicates the engine intake air temperature.

[0126] The controller brings the actual engine charge, high-pressure flow calculation value, low-pressure circuit parameters and atmospheric temperature into the low-pressure flow calculation formula to obtain the low-pressure flow calculation value. The low-pressure flow calculation formula is:

[0127]

[0128] Among them, Q LP_cal Indicates the calculated value of low pressure flow, T h Indicates the mixed gas temperature of the low-pressure circuit, T LP Indicates the low-pressure circuit exhaust gas temperature, T a Indicates the atmospheric temperature.

[0129] The controller performs proportional-integral-differential control on the low-pressure flow calculation value and the low-pressure flow demand value to obtain the low-pressure valve opening adjustment value. Figure 8 Shown is a schematic diagram of the process of obtaining the low-pressure valve opening adjustment value.

[0130] In this embodiment, the actual charge of the engine is obtained through the relevant parameters of the low-pressure circuit and the engine parameters, and then the proportional integral differential control is performed in combination with the low-pressure flow demand value to obtain the low-pressure valve opening adjustment value. The low-pressure valve opening adjustment value can be determined according to different low-pressure circuit working conditions and engine working conditions, which is conducive to improving the exhaust gas circulation control efficiency in the low-pressure circuit, and is conducive to achieving low emissions while having good fuel utilization.

[0131] To explain the exhaust gas recirculation control method and effect in this solution in detail, a most detailed embodiment is described below:

[0132] Application scenarios of exhaust gas recirculation control system for diesel engines. Fig. 9 The figure shows a schematic diagram of the structure of the exhaust gas recirculation control system. The exhaust gas recirculation control system includes an engine unit, a post-processing unit, a high-pressure EGR loop, a low-pressure EGR loop and a controller. Among them, the engine unit includes an engine 1, an intake air temperature sensor 2, an intake air pressure sensor 3, a supercharger 4 and an intercooler 5. The post-processing unit includes a DOC (Diesel Oxidation Catalyst), a DPF (Diesel Particulate Filter), an SCR (Selective Catalytic Reduction) and an ASC (Ammonia Slip Catalyst). In the high-pressure EGR loop, the exhaust gas flows out from the upstream of the turbine of the supercharger 4, passes through the high-pressure EGR valve 21, the high-pressure EGR cooler 22, and the venturi flowmeter 26 in sequence, and mixes with the intake air downstream of the intercooler 5. In the high-pressure EGR loop, a temperature sensor 23, a pressure sensor 24, and a differential pressure sensor 25 are also arranged. In the low-pressure EGR loop, the exhaust gas flows out from between the DPF and the SCR, passes through the low-pressure EGR valve 31 and the low-pressure EGR cooler 32 in sequence, and mixes with the fresh air upstream of the compressor of the supercharger 4. In the low-pressure EGR loop, a sensor 33 for measuring the low-pressure EGR temperature and a sensor 34 for measuring the low-pressure EGR mixed temperature are also arranged.

[0133] The controller is used to execute the exhaust gas recirculation control method. The controller obtains engine parameters and environmental parameters. The engine parameters include engine speed, fuel injection amount, coolant temperature, engine intake pressure and engine intake temperature. The environmental parameters include atmospheric temperature and atmospheric pressure.

[0134] The controller queries the total flow demand spectrum according to the engine speed and the injection amount to obtain the total flow demand basic value. According to the atmospheric temperature, atmospheric pressure and coolant temperature, the controller queries the correction coefficient chart to obtain the atmospheric temperature correction coefficient, atmospheric pressure correction coefficient and coolant temperature correction coefficient respectively. According to the atmospheric temperature correction coefficient, atmospheric pressure correction coefficient and coolant temperature correction coefficient, the comprehensive correction coefficient is obtained, and according to the total flow demand basic value and the comprehensive correction coefficient, the total flow demand value is obtained.

[0135] The controller queries the operating condition table according to the engine speed and the injection amount to determine the target operating condition area. The target operating condition area includes multiple high-pressure flow ratios. In the preset mapping relationship corresponding to each high-pressure flow ratio, the target specific fuel consumption corresponding to the total flow demand value is queried to obtain multiple target specific fuel consumptions; the existing mapping relationship is used to characterize the relationship between the specific fuel consumption and the total flow demand value. The high-pressure flow ratio corresponding to the lowest specific fuel consumption among the multiple target specific fuel consumptions is taken as the optimal high-pressure flow ratio, and the high-pressure flow demand value is determined according to the total flow demand value and the optimal high-pressure flow ratio. The difference between the total flow demand value and the high-pressure flow demand value is taken as the low-pressure flow demand value.

[0136] The controller obtains the high-pressure circuit parameters and the venturi pressure difference. The high-pressure circuit parameters include the high-pressure circuit temperature and the high-pressure circuit pressure. According to the engine parameters, the working condition correction map is queried to obtain the working condition correction coefficient. According to the high-pressure circuit parameters, the venturi pressure difference and the working condition correction coefficient, the high-pressure flow calculation value is determined, and the high-pressure flow calculation value and the high-pressure flow demand value are proportionally, integrally and differentially controlled to obtain the high-pressure valve opening adjustment value.

[0137] The controller obtains low-pressure circuit parameters. The low-pressure circuit parameters include the low-pressure circuit mixed gas temperature and the low-pressure circuit exhaust gas temperature. According to the engine intake pressure and the engine speed, the charging efficiency map is queried to obtain the engine charging efficiency. According to the engine intake pressure, the engine intake temperature, the engine speed, the engine charging efficiency and the engine theoretical charging amount, the actual engine charging amount is obtained, and the low-pressure flow calculation value is determined according to the actual engine charging amount, the high-pressure flow calculation value, the low-pressure circuit parameters and the atmospheric temperature. The low-pressure flow calculation value and the low-pressure flow demand value are controlled by proportional integral differential to obtain the low-pressure valve opening adjustment value.

[0138] The controller obtains the required opening of the high-pressure valve by querying the basic opening map of the high-pressure valve, and determines the opening of the high-pressure valve according to the required opening of the high-pressure valve and the adjustment value of the high-pressure valve opening. The controller obtains the required opening of the low-pressure valve by querying the basic opening map of the low-pressure valve, and determines the opening of the low-pressure valve according to the required opening of the low-pressure valve and the adjustment value of the low-pressure valve opening. The high-pressure valve is set to the high-pressure valve opening, and the low-pressure valve is set to the low-pressure valve opening for exhaust gas recirculation control.

[0139] The above-mentioned exhaust gas recirculation control method determines the high-pressure flow demand value and the low-pressure flow demand value by obtaining the engine parameters and environmental parameters, and obtains the high-pressure valve opening adjustment value and the low-pressure valve opening adjustment value respectively according to the high-pressure flow demand value and the low-pressure flow demand value through proportional integral differential control; determines the high-pressure valve opening according to the high-pressure valve demand opening and the high-pressure valve opening adjustment value; determines the low-pressure valve opening according to the low-pressure valve demand opening and the low-pressure valve opening adjustment value, sets the high-pressure valve to the high-pressure valve opening, and sets the low-pressure valve to the low-pressure valve opening, for exhaust gas recirculation control. The above scheme determines the high-pressure and low-pressure flow demand values ​​based on engine parameters and environmental parameters, and then determines the method of determining the opening of the high-pressure valve and the low-pressure valve. This is beneficial to determining different high-pressure valve and low-pressure valve openings under different engine parameters and environmental parameters, which is beneficial to improving the control efficiency of exhaust gas recirculation; through proportional integral differential control, the high-pressure valve and low-pressure valve opening adjustment values ​​are determined, and then the high-pressure valve and low-pressure valve openings are determined in combination with the high-pressure and low-pressure flow demand values. The exhaust gas recirculation control is performed by the joint work of the high-pressure valve and the low-pressure valve, which is beneficial to reducing emissions while having good fuel utilization.

[0140] It should be understood that, although the various steps in the flowcharts involved in the above-mentioned embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps does not have a strict order restriction, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above-mentioned embodiments can include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

[0141] Based on the same inventive concept, the embodiment of the present application also provides an exhaust gas recirculation control device for implementing the exhaust gas recirculation control method involved above. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme recorded in the above method, so the specific limitations in one or more embodiments of the exhaust gas recirculation control device provided below can refer to the limitations of the exhaust gas recirculation control method above, and will not be repeated here.

[0142] In one embodiment, Fig.10 As shown, an exhaust gas recirculation control device 100 is provided, comprising: an acquisition module 110, a demand determination module 120, a first opening determination module 130, a second opening determination module 140 and a control module 150, wherein:

[0143] An acquisition module 110, used to acquire engine parameters and environmental parameters;

[0144] A demand determination module 120, for determining a high-pressure flow demand value and a low-pressure flow demand value according to engine parameters and environmental parameters;

[0145] The first opening determination module 130 is used to obtain a high-pressure valve opening adjustment value through proportional-integral-differential control according to the high-pressure flow demand value; obtain the high-pressure valve required opening by querying in the high-pressure valve basic opening map; and determine the high-pressure valve opening according to the high-pressure valve required opening and the high-pressure valve opening adjustment value;

[0146] The second opening determination module 140 is used to obtain a low-pressure valve opening adjustment value through proportional integral differential control according to the low-pressure flow demand value; obtain the low-pressure valve required opening by querying the low-pressure valve basic opening spectrum diagram; and determine the low-pressure valve opening according to the low-pressure valve required opening and the low-pressure valve opening adjustment value;

[0147] The control module 150 is used to set the high-pressure valve to a high-pressure valve opening and the low-pressure valve to a low-pressure valve opening for exhaust gas recirculation control.

[0148] The above-mentioned exhaust gas recirculation control device determines the high-pressure flow demand value and the low-pressure flow demand value by obtaining the engine parameters and environmental parameters, and obtains the high-pressure valve opening adjustment value and the low-pressure valve opening adjustment value respectively according to the high-pressure flow demand value and the low-pressure flow demand value through proportional integral differential control; determines the high-pressure valve opening according to the high-pressure valve demand opening and the high-pressure valve opening adjustment value; determines the low-pressure valve opening according to the low-pressure valve demand opening and the low-pressure valve opening adjustment value, sets the high-pressure valve to the high-pressure valve opening, and sets the low-pressure valve to the low-pressure valve opening, for exhaust gas recirculation control. The above scheme determines the high-pressure and low-pressure flow demand values ​​based on engine parameters and environmental parameters, and then determines the method of determining the opening of the high-pressure valve and the low-pressure valve. This is beneficial to determining different high-pressure valve and low-pressure valve openings under different engine parameters and environmental parameters, which is beneficial to improving the control efficiency of exhaust gas recirculation; through proportional integral differential control, the high-pressure valve and low-pressure valve opening adjustment values ​​are determined, and then the high-pressure valve and low-pressure valve openings are determined in combination with the high-pressure and low-pressure flow demand values. The exhaust gas recirculation control is performed by the joint work of the high-pressure valve and the low-pressure valve, which is beneficial to reducing emissions while having good fuel utilization.

[0149] In one embodiment, the engine parameters include engine speed, fuel injection amount and coolant temperature; the high-pressure flow demand value and the low-pressure flow demand value are determined based on the engine parameters and environmental parameters, and the demand determination module 120 is also used to: obtain the total flow demand value based on the engine speed and fuel injection amount; determine the high-pressure flow demand value and the low-pressure flow demand value based on the environmental parameters, coolant temperature and the total flow demand value.

[0150] In one embodiment, the environmental parameters include atmospheric temperature and atmospheric pressure; the total flow demand value is obtained according to the engine speed and the fuel injection amount, and the demand determination module 120 is also used to: query the total flow demand spectrum diagram according to the engine speed and the fuel injection amount to obtain the total flow demand basic value; query the correction coefficient diagram according to the atmospheric temperature, atmospheric pressure and coolant temperature to obtain the atmospheric temperature correction coefficient, atmospheric pressure correction coefficient and coolant temperature correction coefficient respectively; obtain the comprehensive correction coefficient according to the atmospheric temperature correction coefficient, atmospheric pressure correction coefficient and coolant temperature correction coefficient; obtain the total flow demand value according to the total flow demand basic value and the comprehensive correction coefficient.

[0151] In one embodiment, the high-pressure flow demand value and the low-pressure flow demand value are determined according to the environmental parameters, the coolant temperature and the total flow demand value, and the demand determination module 120 is also used to: query the operating condition table according to the engine speed and the injection amount, and determine the target operating condition area; the target operating condition area includes multiple high-pressure flow ratios; in the existing mapping relationship corresponding to each high-pressure flow ratio, query the target specific fuel consumption corresponding to the total flow demand value to obtain multiple target specific fuel consumptions; the existing mapping relationship is used to characterize the relationship between the specific fuel consumption and the total flow demand value; the high-pressure flow ratio corresponding to the lowest specific fuel consumption among the multiple target specific fuel consumptions is used as the optimal high-pressure flow ratio; the high-pressure flow demand value is determined according to the total flow demand value and the optimal high-pressure flow ratio; the difference between the total flow demand value and the high-pressure flow demand value is used as the low-pressure flow demand value.

[0152] In one embodiment, according to the high-pressure flow demand value, a high-pressure valve opening adjustment value is obtained through proportional-integral-differential control, and the first opening determination module 130 is also used to: obtain high-pressure circuit parameters and Venturi tube pressure difference; the high-pressure circuit parameters include high-pressure circuit temperature and high-pressure circuit pressure; according to the engine parameters, query the operating condition correction pulse spectrum to obtain the operating condition correction coefficient; determine the high-pressure flow calculation value according to the high-pressure circuit parameters, the Venturi tube pressure difference and the operating condition correction coefficient; perform proportional-integral-differential control on the high-pressure flow calculation value and the high-pressure flow demand value to obtain the high-pressure valve opening adjustment value.

[0153] In one embodiment, the engine parameters also include engine speed, engine intake pressure and engine intake temperature; the environmental parameters include atmospheric temperature; according to the low-pressure flow demand value, a low-pressure valve opening adjustment value is obtained through proportional integral differential control, and the second opening determination module 140 is also used to: obtain low-pressure circuit parameters; according to the engine intake pressure and the engine speed, query the charging efficiency map to obtain the engine charging efficiency; according to the engine intake pressure, the engine intake temperature, the engine speed, the engine charging efficiency and the engine theoretical charging, obtain the actual engine charging; according to the actual engine charging, the high-pressure flow calculated value, the low-pressure circuit parameters and the atmospheric temperature, determine the low-pressure flow calculated value; perform proportional integral differential control on the low-pressure flow calculated value and the low-pressure flow demand value to obtain the low-pressure valve opening adjustment value.

[0154] Each module in the exhaust gas recirculation control device can be implemented in whole or in part by software, hardware or a combination thereof. Each module can be embedded in or independent of a processor in a computer device in the form of hardware, or can be stored in a memory in a computer device in the form of software, so that the processor can call and execute operations corresponding to each module.

[0155] In one embodiment, a computer device is provided. The computer device may be a terminal, and its internal structure diagram may be as follows: Fig.11 As shown. The computer device includes a processor, a memory, an input / output interface, a communication interface, a display unit and an input device. The processor, the memory and the input / output interface are connected via a system bus, and the communication interface, the display unit and the input device are connected to the system bus via the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be implemented through WIFI, a mobile cellular network, NFC (near field communication) or other technologies. When the computer program is executed by the processor, an exhaust gas recirculation control method is implemented.

[0156] Those skilled in the art will understand that Fig.11 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0157] In one embodiment, a computer device is provided, including a memory and a processor, wherein a computer program is stored in the memory, and when the processor executes the computer program, the following steps are implemented:

[0158] Obtain engine parameters and environmental parameters; determine the high-pressure flow demand value and the low-pressure flow demand value according to the engine parameters and environmental parameters; obtain the high-pressure valve opening adjustment value through proportional-integral-differential control according to the high-pressure flow demand value; obtain the high-pressure valve demand opening by querying in the high-pressure valve basic opening spectrum diagram; determine the high-pressure valve opening according to the high-pressure valve demand opening and the high-pressure valve opening adjustment value; obtain the low-pressure valve opening by querying in the low-pressure valve basic opening spectrum diagram; determine the low-pressure valve opening according to the low-pressure valve demand opening and the low-pressure valve opening adjustment value; set the high-pressure valve to the high-pressure valve opening, and set the low-pressure valve to the low-pressure valve opening for exhaust gas recirculation control.

[0159] In one embodiment, when the processor executes the computer program, the processor further implements the following steps:

[0160] The engine parameters include engine speed, fuel injection amount and coolant temperature; the total flow demand value is obtained according to the engine speed and fuel injection amount; the high-pressure flow demand value and the low-pressure flow demand value are determined according to the environmental parameters, coolant temperature and the total flow demand value.

[0161] In one embodiment, when the processor executes the computer program, the processor further implements the following steps:

[0162] Environmental parameters include atmospheric temperature and atmospheric pressure; according to the engine speed and fuel injection amount, the total flow demand spectrum is queried to obtain the basic value of the total flow demand; according to the atmospheric temperature, atmospheric pressure and coolant temperature, the correction coefficient chart is queried to obtain the atmospheric temperature correction coefficient, atmospheric pressure correction coefficient and coolant temperature correction coefficient respectively; according to the atmospheric temperature correction coefficient, atmospheric pressure correction coefficient and coolant temperature correction coefficient, the comprehensive correction coefficient is obtained; according to the total flow demand basic value and the comprehensive correction coefficient, the total flow demand value is obtained.

[0163] In one embodiment, when the processor executes the computer program, the processor further implements the following steps:

[0164] According to the engine speed and the injection amount, the operating condition table is queried to determine the target operating condition area; the target operating condition area includes multiple high-pressure flow ratios; in the existing mapping relationship corresponding to each high-pressure flow ratio, the target specific fuel consumption corresponding to the total flow demand value is queried to obtain multiple target specific fuel consumptions; the existing mapping relationship is used to characterize the relationship between the specific fuel consumption and the total flow demand value; the high-pressure flow ratio corresponding to the lowest specific fuel consumption among the multiple target specific fuel consumptions is used as the optimal high-pressure flow ratio; the high-pressure flow demand value is determined according to the total flow demand value and the optimal high-pressure flow ratio; the difference between the total flow demand value and the high-pressure flow demand value is used as the low-pressure flow demand value.

[0165] In one embodiment, when the processor executes the computer program, the processor further implements the following steps:

[0166] Obtain high-pressure circuit parameters and Venturi tube pressure difference; high-pressure circuit parameters include high-pressure circuit temperature and high-pressure circuit pressure; query the operating condition correction pulse spectrum according to the engine parameters to obtain the operating condition correction coefficient; determine the high-pressure flow calculation value according to the high-pressure circuit parameters, the Venturi tube pressure difference and the operating condition correction coefficient; perform proportional-integral-differential control on the high-pressure flow calculation value and the high-pressure flow demand value to obtain the high-pressure valve opening adjustment value.

[0167] In one embodiment, when the processor executes the computer program, the processor further implements the following steps:

[0168] The engine parameters also include engine speed, engine intake pressure and engine intake temperature; the environmental parameters include atmospheric temperature; obtain low-pressure circuit parameters; query the charging efficiency spectrum according to the engine intake pressure and engine speed to obtain the engine charging efficiency; obtain the actual engine charging according to the engine intake pressure, engine intake temperature, engine speed, engine charging efficiency and engine theoretical charging; determine the low-pressure flow calculation value according to the actual engine charging, the high-pressure flow calculation value, the low-pressure circuit parameters and the atmospheric temperature; perform proportional-integral-differential control on the low-pressure flow calculation value and the low-pressure flow demand value to obtain the low-pressure valve opening adjustment value.

[0169] In one embodiment, a computer readable storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the following steps are implemented:

[0170] Obtain engine parameters and environmental parameters; determine the high-pressure flow demand value and the low-pressure flow demand value according to the engine parameters and environmental parameters; obtain the high-pressure valve opening adjustment value through proportional-integral-differential control according to the high-pressure flow demand value; obtain the high-pressure valve demand opening by querying in the high-pressure valve basic opening spectrum diagram; determine the high-pressure valve opening according to the high-pressure valve demand opening and the high-pressure valve opening adjustment value; obtain the low-pressure valve opening by querying in the low-pressure valve basic opening spectrum diagram; determine the low-pressure valve opening according to the low-pressure valve demand opening and the low-pressure valve opening adjustment value; set the high-pressure valve to the high-pressure valve opening, and set the low-pressure valve to the low-pressure valve opening for exhaust gas recirculation control.

[0171] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0172] The engine parameters include engine speed, fuel injection amount and coolant temperature; the total flow demand value is obtained according to the engine speed and fuel injection amount; the high-pressure flow demand value and the low-pressure flow demand value are determined according to the environmental parameters, coolant temperature and the total flow demand value.

[0173] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0174] Environmental parameters include atmospheric temperature and atmospheric pressure; according to the engine speed and fuel injection amount, the total flow demand spectrum is queried to obtain the basic value of the total flow demand; according to the atmospheric temperature, atmospheric pressure and coolant temperature, the correction coefficient chart is queried to obtain the atmospheric temperature correction coefficient, atmospheric pressure correction coefficient and coolant temperature correction coefficient respectively; according to the atmospheric temperature correction coefficient, atmospheric pressure correction coefficient and coolant temperature correction coefficient, the comprehensive correction coefficient is obtained; according to the total flow demand basic value and the comprehensive correction coefficient, the total flow demand value is obtained.

[0175] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0176] According to the engine speed and the injection amount, the operating condition table is queried to determine the target operating condition area; the target operating condition area includes multiple high-pressure flow ratios; in the existing mapping relationship corresponding to each high-pressure flow ratio, the target specific fuel consumption corresponding to the total flow demand value is queried to obtain multiple target specific fuel consumptions; the existing mapping relationship is used to characterize the relationship between the specific fuel consumption and the total flow demand value; the high-pressure flow ratio corresponding to the lowest specific fuel consumption among the multiple target specific fuel consumptions is used as the optimal high-pressure flow ratio; the high-pressure flow demand value is determined according to the total flow demand value and the optimal high-pressure flow ratio; the difference between the total flow demand value and the high-pressure flow demand value is used as the low-pressure flow demand value.

[0177] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0178] Obtain high-pressure circuit parameters and Venturi tube pressure difference; high-pressure circuit parameters include high-pressure circuit temperature and high-pressure circuit pressure; query the operating condition correction pulse spectrum according to the engine parameters to obtain the operating condition correction coefficient; determine the high-pressure flow calculation value according to the high-pressure circuit parameters, the Venturi tube pressure difference and the operating condition correction coefficient; perform proportional-integral-differential control on the high-pressure flow calculation value and the high-pressure flow demand value to obtain the high-pressure valve opening adjustment value.

[0179] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0180] The engine parameters also include engine speed, engine intake pressure and engine intake temperature; the environmental parameters include atmospheric temperature; obtain low-pressure circuit parameters; query the charging efficiency spectrum according to the engine intake pressure and engine speed to obtain the engine charging efficiency; obtain the actual engine charging according to the engine intake pressure, engine intake temperature, engine speed, engine charging efficiency and engine theoretical charging; determine the low-pressure flow calculation value according to the actual engine charging, the high-pressure flow calculation value, the low-pressure circuit parameters and the atmospheric temperature; perform proportional-integral-differential control on the low-pressure flow calculation value and the low-pressure flow demand value to obtain the low-pressure valve opening adjustment value.

[0181] In one embodiment, a computer program product is provided, comprising a computer program, which, when executed by a processor, implements the following steps:

[0182] Obtain engine parameters and environmental parameters; determine the high-pressure flow demand value and the low-pressure flow demand value according to the engine parameters and environmental parameters; obtain the high-pressure valve opening adjustment value through proportional-integral-differential control according to the high-pressure flow demand value; obtain the high-pressure valve demand opening by querying in the high-pressure valve basic opening spectrum diagram; determine the high-pressure valve opening according to the high-pressure valve demand opening and the high-pressure valve opening adjustment value; obtain the low-pressure valve opening by querying in the low-pressure valve basic opening spectrum diagram; determine the low-pressure valve opening according to the low-pressure valve demand opening and the low-pressure valve opening adjustment value; set the high-pressure valve to the high-pressure valve opening, and set the low-pressure valve to the low-pressure valve opening for exhaust gas recirculation control.

[0183] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0184] The engine parameters include engine speed, fuel injection amount and coolant temperature; the total flow demand value is obtained according to the engine speed and fuel injection amount; the high-pressure flow demand value and the low-pressure flow demand value are determined according to the environmental parameters, coolant temperature and the total flow demand value.

[0185] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0186] Environmental parameters include atmospheric temperature and atmospheric pressure; according to the engine speed and fuel injection amount, the total flow demand spectrum is queried to obtain the basic value of the total flow demand; according to the atmospheric temperature, atmospheric pressure and coolant temperature, the correction coefficient chart is queried to obtain the atmospheric temperature correction coefficient, atmospheric pressure correction coefficient and coolant temperature correction coefficient respectively; according to the atmospheric temperature correction coefficient, atmospheric pressure correction coefficient and coolant temperature correction coefficient, the comprehensive correction coefficient is obtained; according to the total flow demand basic value and the comprehensive correction coefficient, the total flow demand value is obtained.

[0187] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0188] According to the engine speed and the injection amount, the operating condition table is queried to determine the target operating condition area; the target operating condition area includes multiple high-pressure flow ratios; in the existing mapping relationship corresponding to each high-pressure flow ratio, the target specific fuel consumption corresponding to the total flow demand value is queried to obtain multiple target specific fuel consumptions; the existing mapping relationship is used to characterize the relationship between the specific fuel consumption and the total flow demand value; the high-pressure flow ratio corresponding to the lowest specific fuel consumption among the multiple target specific fuel consumptions is used as the optimal high-pressure flow ratio; the high-pressure flow demand value is determined according to the total flow demand value and the optimal high-pressure flow ratio; the difference between the total flow demand value and the high-pressure flow demand value is used as the low-pressure flow demand value.

[0189] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0190] Obtain high-pressure circuit parameters and Venturi tube pressure difference; high-pressure circuit parameters include high-pressure circuit temperature and high-pressure circuit pressure; query the operating condition correction pulse spectrum according to the engine parameters to obtain the operating condition correction coefficient; determine the high-pressure flow calculation value according to the high-pressure circuit parameters, the Venturi tube pressure difference and the operating condition correction coefficient; perform proportional-integral-differential control on the high-pressure flow calculation value and the high-pressure flow demand value to obtain the high-pressure valve opening adjustment value.

[0191] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0192] The engine parameters also include engine speed, engine intake pressure and engine intake temperature; the environmental parameters include atmospheric temperature; obtain low-pressure circuit parameters; query the charging efficiency spectrum according to the engine intake pressure and engine speed to obtain the engine charging efficiency; obtain the actual engine charging according to the engine intake pressure, engine intake temperature, engine speed, engine charging efficiency and engine theoretical charging; determine the low-pressure flow calculation value according to the actual engine charging, the high-pressure flow calculation value, the low-pressure circuit parameters and the atmospheric temperature; perform proportional-integral-differential control on the low-pressure flow calculation value and the low-pressure flow demand value to obtain the low-pressure valve opening adjustment value.

[0193] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant laws, regulations and standards of relevant countries and regions.

[0194] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited to this. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but are not limited to this.

[0195] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0196] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. An exhaust gas recirculation control method, It is characterized in that The method comprises: Obtain engine parameters and environmental parameters; Determining a high-pressure flow demand value and a low-pressure flow demand value according to the engine parameters and the environmental parameters; According to the high-pressure flow demand value, a high-pressure valve opening adjustment value is obtained through proportional-integral-differential control; the high-pressure valve required opening is obtained by querying in the high-pressure valve basic opening spectrum diagram; the high-pressure valve opening is determined according to the high-pressure valve required opening and the high-pressure valve opening adjustment value; According to the low-pressure flow demand value, a low-pressure valve opening adjustment value is obtained through proportional-integral-differential control; the low-pressure valve required opening is obtained by querying in the low-pressure valve basic opening spectrum diagram; the low-pressure valve opening is determined according to the low-pressure valve required opening and the low-pressure valve opening adjustment value; The high-pressure valve is set to the high-pressure valve opening, and the low-pressure valve is set to the low-pressure valve opening, for exhaust gas recirculation control.

2. The method according to claim 1, It is characterized in that The engine parameters include engine speed, fuel injection amount and coolant temperature; Determining a high-pressure flow demand value and a low-pressure flow demand value according to the engine parameter and the environmental parameter includes: Obtaining a total flow demand value according to the engine speed and the fuel injection amount; A high-pressure flow requirement value and a low-pressure flow requirement value are determined according to the environmental parameter, the coolant temperature and the total flow requirement value.

3. The method according to claim 2, It is characterized in that The environmental parameters include atmospheric temperature and atmospheric pressure; The total flow demand value is obtained according to the engine speed and the fuel injection amount, including: According to the engine speed and the fuel injection amount, query the total flow demand map to obtain a total flow demand basic value; According to the atmospheric temperature, the atmospheric pressure and the coolant temperature, query the correction coefficient chart to obtain the atmospheric temperature correction coefficient, the atmospheric pressure correction coefficient and the coolant temperature correction coefficient respectively; Obtaining a comprehensive correction coefficient according to the atmospheric temperature correction coefficient, the atmospheric pressure correction coefficient and the coolant temperature correction coefficient; The total flow demand value is obtained according to the total flow demand basic value and the comprehensive correction coefficient.

4. The method according to claim 2, It is characterized in that The step of determining the high-pressure flow requirement value and the low-pressure flow requirement value according to the environmental parameter, the coolant temperature and the total flow requirement value comprises: According to the engine speed and the fuel injection amount, query the operating condition table to determine the target operating condition area; the target operating condition area includes a plurality of high-pressure flow ratios; In the stored mapping relationship corresponding to each high-pressure flow ratio, the target specific fuel consumption corresponding to the total flow demand value is queried to obtain multiple target specific fuel consumptions; the stored mapping relationship is used to characterize the relationship between the specific fuel consumption and the total flow demand value; taking the high pressure flow rate ratio corresponding to the lowest specific fuel consumption among the multiple target specific fuel consumptions as the optimal high pressure flow rate ratio; Determining a high-pressure flow demand value according to the total flow demand value and the optimal high-pressure flow ratio; The difference between the total flow demand value and the high-pressure flow demand value is used as the low-pressure flow demand value.

5. The method according to claim 1, It is characterized in that The method of obtaining the high-pressure valve opening adjustment value through proportional-integral-differential control according to the high-pressure flow demand value includes: Obtaining high-pressure circuit parameters and venturi tube pressure difference; the high-pressure circuit parameters include high-pressure circuit temperature and high-pressure circuit pressure; According to the engine parameters, query the operating condition correction map to obtain the operating condition correction coefficient; Determining a high-pressure flow calculation value according to the high-pressure circuit parameters, the venturi tube pressure difference and the operating condition correction coefficient; The high-pressure flow calculation value and the high-pressure flow demand value are subjected to proportional-integral-differential control to obtain a high-pressure valve opening adjustment value.

6. The method according to claim 5, It is characterized in that The engine parameters also include engine speed, engine intake pressure and engine intake temperature; the environmental parameters include atmospheric temperature; The method of obtaining the low-pressure valve opening adjustment value through proportional-integral-differential control according to the low-pressure flow demand value includes: Get low voltage circuit parameters; According to the engine intake pressure and the engine speed, query the charging efficiency map to obtain the engine charging efficiency; Obtaining an actual charge of the engine according to the engine intake pressure, the engine intake temperature, the engine speed, the engine charging efficiency and the engine theoretical charge; Determine a low-pressure flow rate calculation value according to the actual charge of the engine, the high-pressure flow rate calculation value, the low-pressure circuit parameter and the atmospheric temperature; The low-pressure flow calculation value and the low-pressure flow demand value are subjected to proportional-integral-differential control to obtain a low-pressure valve opening adjustment value.

7. An exhaust gas recirculation control device, It is characterized in that The device comprises: An acquisition module, used to acquire engine parameters and environmental parameters; A demand determination module, used for determining a high-pressure flow demand value and a low-pressure flow demand value according to the engine parameters and the environmental parameters; A first opening determination module is used to obtain a high-pressure valve opening adjustment value through proportional-integral-differential control according to the high-pressure flow demand value; obtain the high-pressure valve required opening by querying in the high-pressure valve basic opening map; and determine the high-pressure valve opening according to the high-pressure valve required opening and the high-pressure valve opening adjustment value; A second opening determination module is used to obtain a low-pressure valve opening adjustment value through proportional integral differential control according to the low-pressure flow demand value; obtain the low-pressure valve required opening by querying in the low-pressure valve basic opening spectrum diagram; and determine the low-pressure valve opening according to the low-pressure valve required opening and the low-pressure valve opening adjustment value; The control module is used to set the high-pressure valve to the high-pressure valve opening and the low-pressure valve to the low-pressure valve opening for exhaust gas recirculation control.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program. It is characterized in that When the processor executes the computer program, the steps of the method according to any one of claims 1 to 6 are implemented.

9. A computer-readable storage medium having a computer program stored thereon, It is characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

10. A computer program product comprising a computer program, It is characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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