Turbocharged engine and EGR intake flow calculation system

Abstract

The invention discloses a turbocharged engine and an EGR intake flow calculation system, and relates to the field of engines, and the engine comprises an engine main body used for engine intake, exhaust and combustion places; the turbocharger is used for improving the air inflow of the engine; the EGR intercooler is used for cooling EGR high-temperature gas; the EGR valve is used for adjusting EGR gas flow; the air inlet intercooler is used for cooling the fresh air compressed by the air compressor; the throttle valve is used for adjusting the fresh air inlet amount; the air inlet mixer is used for mixing EGR gas with fresh air; the sensor is used for collecting state information of the engine; the ECU control system is used for receiving a sensor signal value; the method comprises the steps of obtaining pre-stored calibration data; the ECU control system controls the engine to operate according to a preset operation state according to the calibration data and the sensor signal value; the step of controlling the engine to operate according to the preset operation state comprises the step that the ECU control system regulates and controls the opening degree of the North crown valve, the opening degree of the throttle valve and the opening degree of the EGR valve.

Description

Technical Field

[0001] This application relates to the field of engines, and particularly to a turbocharged engine, an EGR intake air flow calculation system, an EGR intake air flow calculation method, an EGR intake air flow calculation device, an electronic device, a storage medium, and a vehicle. Background Art

[0002] The engine EGR technology (Exhaust Gas Recirculation) is to introduce a certain amount of exhaust gas into the cylinder combustion chamber again to participate in combustion after being cooled by an intercooler. Since the exhaust gas contains gases such as CO2, water vapor, and N2, the heat capacity of the mixture entering the cylinder is increased, the highest combustion temperature in the cylinder is decreased, the high-temperature generation conditions of NOX are inhibited, and thus the concentration of NOX in the engine exhaust is reduced.

[0003] Existing turbocharged engines using EGR technology usually use a Venturi tube flowmeter or a MAF (Mass Air Flow) sensor to calculate the EGR intake air flow. Among them, the Venturi tube flowmeter is a device based on Bernoulli's principle and is used to measure the flow rate of a fluid (liquid or gas) passing through a pipeline. It consists of a tube section that gradually contracts and then gradually expands. This shape causes the fluid to increase in velocity and decrease in pressure when passing through the narrowest part (throat). By measuring this pressure difference, the flow rate of the fluid can be calculated. The MAF sensor controls the EGR intake air flow through an intake air flow closed-loop. However, in actual application on an engine, the Venturi tube flowmeter has disadvantages such as high cost, complex structure, and strict installation requirements, which easily lead to inaccurate EGR flow calculation, unstable EGR rate control, etc. The MAF sensor is sensitive to the layout of the supercharger and the EGR pipeline, and the engine emission consistency is poor, which affects the engine performance and the overall engine economy decreases.

[0004] Therefore, a turbocharged engine and a supporting EGR intake air flow calculation scheme are needed to simplify the calculation logic, simplify the EGR intake air flow calculation method and calculation system, and reduce the consumption of calculation resources. Summary of the Invention

[0005] The purpose of the present invention is to provide a turbocharged engine, an EGR intake air flow calculation system, an EGR intake air flow calculation method, an EGR intake air flow calculation device, an electronic device, a storage medium, and a vehicle, which can at least solve one of the technical problems of simplifying the EGR intake air flow calculation and reducing the consumption of calculation resources.

[0006] The present invention provides the following solutions:

[0007] According to one aspect of the present invention, there is provided a turbocharged engine, which includes: an engine body, a turbocharger, an EGR intercooler, an EGR valve, an intake air intercooler, a throttle valve, an intake air mixer, and sensors;

[0008] The engine body is used for the intake, exhaust, and combustion of the engine;

[0009] The turbocharger is used to increase the intake air volume of the engine;

[0010] The EGR intercooler is used to cool the high-temperature EGR gas;

[0011] The EGR valve is used to regulate the flow rate of the EGR gas;

[0012] The intake air intercooler is used to cool the fresh air compressed by the compressor;

[0013] The throttle valve is used to regulate the intake air volume of the fresh air;

[0014] The intake air mixer is used for the mixing of the EGR gas and the fresh air;

[0015] The sensors are used to collect the state information of the engine;

[0016] Among them, the sensors include an initial intake air pressure sensor, an initial intake air temperature sensor, a turbocharger speed sensor, a boost pressure sensor, an intake manifold TMAP sensor, and an engine speed sensor;

[0017] It further includes an ECU control system for receiving the sensor signal values;

[0018] Among them, pre-stored calibration data is obtained;

[0019] The ECU control system controls the engine to operate according to a preset operating state based on the calibration data and the sensor signal values;

[0020] Controlling the engine to operate according to a preset operating state includes that the ECU control system regulates the opening degrees of the Norgren valve, the throttle valve, and the EGR valve.

[0021] According to another aspect of the present invention, there is provided an EGR intake air flow calculation system, which includes: a signal acquisition unit, a signal determination unit, a first calculation unit, a second calculation unit, and a signal output unit;

[0022] The signal acquisition unit is used to acquire the sensor signal values of the engine and transmit them to the ECU control system in real time;

[0023] The signal determination unit is used to determine the operating state of the engine;

[0024] A first calculation unit for obtaining an initial fresh air quantity L1 flowing through a compressor and a corrected fresh air intake quantity L2;

[0025] A second calculation unit for obtaining a total air quantity L0 entering the engine;

[0026] A signal output unit for calculating a difference between the total air quantity L0 entering the engine and the corrected fresh air intake quantity L2 to obtain an EGR intake flow rate L3.

[0027] According to three aspects of the present invention, an EGR intake flow rate calculation method is provided. The EGR intake flow rate calculation method includes:

[0028] Collecting sensor signal values;

[0029] Obtaining engine state data according to the sensor signal values;

[0030] Among them, the engine state data includes an initial intake pressure value P1 and a post-boost air pressure value P2;

[0031] According to the formula Obtaining a boost pressure ratio α of a front engine turbocharger.

[0032] Further, the engine state data further includes: an engine turbocharger rotational speed value R1;

[0033] Obtaining a turbocharger compressor performance MAP table;

[0034] Obtaining an initial fresh air quantity L1 flowing through the compressor according to the boost pressure ratio α, the turbocharger rotational speed R1, and the turbocharger compressor performance MAP table.

[0035] Further, the engine state data further includes an engine initial intake temperature value T1;

[0036] Obtaining a temperature correction coefficient chart;

[0037] Obtaining a corresponding initial temperature correction coefficient K1 according to the temperature correction coefficient chart and the initial intake temperature value T1;

[0038] Calculating a product of the initial intake temperature correction coefficient K1 and the above-mentioned initial fresh air quantity L1 to obtain a corrected fresh air intake quantity L2.

[0039] Further, the engine state data further includes: an intake temperature T2 and an intake pressure P3 of an engine intake manifold;

[0040] Obtaining a total air quantity L0 entering the engine according to the intake temperature T2 and the intake pressure P3 of the engine intake manifold;

[0041] According to the corrected fresh air intake volume L2 and the total air volume L0 entering the engine, obtain the difference between the total air volume L0 entering the engine and the corrected fresh air intake volume L2;

[0042] According to the difference between the total air volume L0 entering the engine and the corrected fresh air intake volume L2, obtain the EGR intake flow rate L3.

[0043] According to four aspects of the present invention, there is provided an EGR intake flow rate calculation device, and the EGR intake flow rate calculation device includes:

[0044] A signal acquisition module, configured to acquire sensor signal values;

[0045] An engine state module, configured to obtain engine state data according to the sensor signal values;

[0046] Wherein, the engine state data includes an initial intake pressure value P1 and a supercharged air pressure value P2;

[0047] An algorithm module, configured to obtain the supercharging pressure ratio α of the front engine turbocharger according to the formula

[0048] According to five aspects of the present invention, there is provided an electronic device, including: a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory complete mutual communication through the communication bus;

[0049] The memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the EGR intake flow rate calculation method.

[0050] According to six aspects of the present invention, there is provided a computer-readable storage medium, which stores a computer program executable by an electronic device. When the computer program runs on the electronic device, the electronic device executes the steps of the EGR intake flow rate calculation method.

[0051] According to seven aspects of the present invention, there is provided a vehicle, including:

[0052] An electronic device, configured to implement the steps of the EGR intake flow rate calculation method;

[0053] A processor, the processor runs a program, and when the program runs, it executes the steps of the EGR intake flow rate calculation method according to the data output from the electronic device;

[0054] A storage medium, configured to store a program, and when the program runs, it executes the steps of the EGR intake flow rate calculation method for the data output from the electronic device.

[0055] ​Through the above solution, the following beneficial technical effects are obtained:

[0056] In this application, the initial pressure value of the fresh air at the compressor inlet of the engine turbocharger and the pressure value of the fresh air after supercharging at the compressor outlet are collected, the pressure ratio of the compressor of the supercharger under the current state is calculated, and then the fresh air intake flow value flowing through the compressor under the current state is obtained by querying the compressor performance MAP table in combination with the supercharger speed value. Then, according to the initial intake temperature value, the corresponding initial intake temperature correction coefficient is determined, and the product of the fresh air intake flow value and the temperature correction coefficient is calculated to obtain the corrected fresh air intake flow value, optimizing the calculation method.

[0057] In this application, the total air volume currently entering the engine is obtained through the TMAP sensor provided on the engine intake manifold, and the difference between this total air volume and the fresh air intake flow value is calculated, and then the EGR intake flow value of the engine under the current state can be obtained, simplifying the calculation process.

[0058] In this application, by setting a turbocharger speed sensor, an initial intake pressure and intake temperature sensor, a boost pressure sensor, an intake manifold TMAP sensor, and the original basic sensors of the engine, the current operating state of the engine can be determined in real time. Then, in combination with the signal acquisition unit, signal determination unit, first calculation unit, second calculation unit, and signal output unit in the EGR intake flow calculation system, the fresh air intake volume, EGR intake flow, and total intake volume of the engine can be accurately obtained by using the preset performance MAP tables and calculation processes in each unit, so as to achieve precise control of the engine EGR rate, reduce NOX emissions, and improve the overall emission performance and economy. Description of the Drawings

[0059] Figure 1 is a structural diagram of a turbocharged engine provided by one or more embodiments of the present invention.

[0060] Figure 2 is a structural diagram of an EGR intake flow calculation system provided by one or more embodiments of the present invention.

[0061] Figure 3 is a flowchart of an EGR intake flow calculation method provided by one or more embodiments of the present invention.

[0062] Figure 4 is a structural diagram of an EGR intake flow calculation device provided by one or more embodiments of the present invention.

[0063] Figure 5 is a schematic diagram of the structure of a turbocharged engine according to a specific embodiment of the present invention.

[0064] Figure 6It is a schematic diagram of the calculation method flow of the EGR intake air flow rate in a specific embodiment of the present invention.

[0065] Figure 7 It is a schematic diagram of the process of determining the initial intake air temperature correction coefficient in the calculation method of the EGR intake air flow rate in a specific embodiment of the present invention.

[0066] Figure 8 It is a schematic diagram of the process of determining the corrected fresh air quantity in the calculation method of the EGR intake air flow rate in a specific embodiment of the present invention.

[0067] Figure 9 It is a schematic diagram of the process of determining the EGR intake air flow rate in the calculation method of the EGR intake air flow rate in a specific embodiment of the present invention.

[0068] Figure 10 It is a schematic diagram of the structure of the calculation system of the EGR intake air flow rate in a specific embodiment of the present invention.

[0069] Figure 11 It is a block diagram of the structure of an electronic device for the EGR intake air flow rate calculation method provided by one or more embodiments of the present invention.

[0070] Reference numerals:

[0071] 1. ECU control system; 2. Exhaust manifold; 3. Exhaust gas bypass valve; 4. Exhaust branch pipe; 5. Turbine; 6. Turbine speed sensor; 7. Compressor; 8. Initial intake air pressure sensor; 9. Initial intake air temperature sensor; 10. Initial intake main pipe; 11. Exhaust manifold; 12. Boost pressure sensor; 13. Intercooler; 14. Throttle valve; 15. TMAP sensor; 16. Intake main pipe; 17. Intake mixer; 18. EGR valve; 19. EGR pipeline; 20. Engine body; 21. Turbocharger; 22. EGR intercooler; 23. Sensor assembly and its connecting wire harness; 24. Norgren valve.

[0072] A10. Signal acquisition unit; A20. Signal determination unit; A30. First calculation unit; A40. Second calculation unit; A50. Signal output unit. Detailed implementation manners

[0073] Next, the technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings. Obviously, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0074] Figure 1It is a structural diagram of a turbocharged engine provided by one or more embodiments of the present invention.

[0075] As Figure 1 shown, the turbocharged engine includes: an engine body, a turbocharger, an EGR intercooler, an EGR valve, an intake air intercooler, a throttle valve, an intake mixer, and sensors; the engine body is used as the place for engine intake, exhaust, and combustion; the turbocharger is used to increase the engine intake air volume; the EGR intercooler is used to cool the EGR high-temperature gas; the EGR valve is used to regulate the EGR gas flow; the intake air intercooler is used to cool the fresh air compressed by the compressor; the throttle valve is used to regulate the fresh air intake volume; the intake mixer is used for the mixing of the EGR gas and the fresh air; the sensors are used to collect the state information of the engine; among them, the sensors include an initial intake air pressure sensor, an initial intake air temperature sensor, a turbocharger speed sensor, a boost pressure sensor, an intake manifold TMAP sensor, and an engine speed sensor; it also includes an ECU control system for receiving the sensor signal values; among them, pre-stored calibration data is obtained; the ECU control system controls the engine to operate in a preset operating state according to the calibration data and the sensor signal values; controlling the engine to operate in a preset operating state includes that the ECU control system regulates the opening degrees of the Norgren valve, the throttle valve, and the EGR valve.

[0076] Figure 2 It is a structural diagram of an EGR intake air flow calculation system provided by one or more embodiments of the present invention.

[0077] As Figure 2 shown, the EGR intake air flow calculation system includes: a signal acquisition unit, a signal determination unit, a first calculation unit, a second calculation unit, and a signal output unit; the signal acquisition unit is used to acquire the sensor signal values of the engine and transmit them to the ECU control system in real time; the signal determination unit is used to determine the engine operating state; the first calculation unit is used to obtain the initial fresh air volume L1 flowing through the compressor and the corrected fresh air intake volume L2; the second calculation unit is used to obtain the total air volume L0 entering the engine; the signal output unit is used to calculate the difference between the total air volume L0 entering the engine and the corrected fresh air intake volume L2 to obtain the EGR intake air flow L3.

[0078] Figure 3 It is a flowchart of an EGR intake air flow calculation method provided by one or more embodiments of the present invention.

[0079] As Figure 3The EGR intake air flow calculation method shown includes: Step S1, collecting sensor signal values; Step S2, obtaining engine state data according to the sensor signal values; where the engine state data includes the initial intake air pressure value P1 and the pressurized air pressure value P2 after supercharging; Step S3, according to the formula obtain the supercharging pressure ratio α of the front engine turbocharger.

[0080] In this embodiment, the engine state data further includes: the engine turbocharger speed value R1; obtaining the turbocharger compressor performance MAP table; according to the supercharging pressure ratio α, the turbocharger speed R1, and the turbocharger compressor performance MAP table, obtaining the initial fresh air volume L1 flowing through the compressor.

[0081] In this embodiment, the engine state data further includes the engine initial intake air temperature value T1; obtaining the temperature correction coefficient chart; according to the temperature correction coefficient chart and the initial intake air temperature value T1, obtaining the corresponding initial temperature correction coefficient K1; calculating the product of the initial temperature correction coefficient K1 and the above-mentioned initial fresh air volume L1 to obtain the corrected fresh air intake volume L2.

[0082] In this embodiment, the engine state data further includes: the intake air temperature T2 and the intake air pressure P3 of the engine intake manifold; according to the intake air temperature T2 and the intake air pressure P3 of the engine intake manifold, obtaining the total air volume L0 entering the engine; according to the corrected fresh air intake volume L2 and the total air volume L0 entering the engine, obtaining the difference between the total air volume L0 entering the engine and the corrected fresh air intake volume L2; according to the difference between the total air volume L0 entering the engine and the corrected fresh air intake volume L2, obtaining the EGR intake air flow L3.

[0083] Figure 4 is the structural diagram of the EGR intake air flow calculation device provided by one or more embodiments of the present invention.

[0084] As Figure 4 shown, the EGR intake air flow calculation device includes: a signal acquisition module for collecting sensor signal values; an engine state module for obtaining engine state data according to the sensor signal values; where the engine state data includes the initial intake air pressure value P1 and the pressurized air pressure value P2 after supercharging; an algorithm module for obtaining the supercharging pressure ratio α of the front engine turbocharger according to the formula obtain the supercharging pressure ratio α of the front engine turbocharger.

[0085] It should be noted that although this system only discloses a signal acquisition module, an engine status module, and an algorithm module, it does not mean that this device is only limited to the above basic functional modules. On the contrary, what the present invention intends to express is that based on the above basic functional modules, those skilled in the art can arbitrarily add one or more functional modules in combination with the existing technology to form an infinite number of embodiments or technical solutions. That is to say, this system is open rather than closed. It cannot be considered that the protection scope of the claims of the present invention is limited to the above disclosed basic functional modules just because only individual basic functional modules are disclosed in this embodiment.

[0086] Figure 5 It is a schematic diagram of the structure of a turbocharged engine according to a specific embodiment of the present invention.

[0087] Figure 6 It is a schematic diagram of the flow of a method for calculating the EGR intake air flow according to a specific embodiment of the present invention.

[0088] Figure 7 It is a schematic diagram of the process for determining the initial intake air temperature correction coefficient in the method for calculating the EGR intake air flow according to a specific embodiment of the present invention.

[0089] Figure 8 It is a schematic diagram of the process for determining the corrected fresh air quantity in the method for calculating the EGR intake air flow according to a specific embodiment of the present invention.

[0090] Figure 9 It is a schematic diagram of the process for determining the EGR intake air flow in the method for calculating the EGR intake air flow according to a specific embodiment of the present invention.

[0091] Figure 10 It is a schematic diagram of the structure of a system for calculating the EGR intake air flow according to a specific embodiment of the present invention.

[0092] In a specific embodiment, as Figure 5 shown, the engine mainly includes an engine body 20, a turbocharger, an EGR intercooler 22, an EGR valve 18, an intake air intercooler 13, a throttle valve 14, an intake air mixer 17, a Norgren valve 24, an exhaust gas bypass valve 3, an ECU control system 1, a sensor assembly, and its connecting wire harness 23. The sensor assembly mainly includes an initial intake air pressure sensor 8, an initial intake air temperature sensor 9, a turbocharger speed sensor 6, a boost pressure sensor 12, and a TMAP sensor 15.

[0093] In this embodiment, the engine body is the place where the engine completes intake, exhaust, and combustion work. It is mainly composed of components such as an engine cylinder head and a cylinder block. Among them, the intake manifold 16 is connected to the intake side of the cylinder head and is responsible for engine intake. The exhaust manifold 11 is connected to the exhaust side of the cylinder head and is responsible for discharging engine exhaust gas;

[0094] In this embodiment, the turbocharger consists of a turbine 5, a compressor 7, an exhaust gas bypass valve 3, an exhaust manifold 4, and a turbocharger speed sensor 6. The turbine 5 and the compressor 7 are coaxially connected, and the rotation of the turbine 5 blades drives the rotation of the compressor 7 blades;

[0095] In this embodiment, after the engine exhaust gas flows into the exhaust manifold 11, it is divided into three branches. Most of the exhaust gas flows to the turbine 4 to drive the turbine blades to rotate and do work, and then flows to the exhaust main pipe 2. Another part of the exhaust gas can flow to the exhaust main pipe 2 through the exhaust gas bypass valve 3 and the exhaust manifold 4. The last part of the exhaust gas flows to the EGR intake pipeline as EGR gas;

[0096] In this embodiment, the exhaust gas bypass valve 3 is responsible for regulating the flow rate of the exhaust gas bypass branch to achieve controllable regulation of the pressure in front of the turbine and the speed of the turbocharger;

[0097] In this embodiment, the turbocharger speed sensor 6 is used to monitor the speed of the turbocharger in real time and feedback the speed information to the ECU control system 1;

[0098] In this embodiment, the electric Norgren valve 24 is connected to the ECU control system and the exhaust gas bypass valve 3, and the opening of the exhaust gas bypass valve 3 is adjusted under the ECU instruction, so as to realize the electric control of the flow rate of the exhaust gas bypass branch;

[0099] In this embodiment, the EGR intake pipeline consists of an EGR intercooler 22, an EGR intake pipe 19, and an EGR valve 18. After the above-mentioned engine exhaust gas flows out of the exhaust manifold 11, a part of the exhaust gas flows to the EGR intercooler 22 for cooling, and the cooled EGR gas flows to the EGR valve 18 through the EGR pipeline 19;

[0100] In this embodiment, the EGR valve 18 is connected to the ECU control system 1, and the opening is adjusted under the ECU instruction, so as to realize the controllable regulation of the EGR intake flow rate;

[0101] In this embodiment, the initial intake main pipe 10 of the present invention is connected to the inlet of the compressor 7, responsible for the entry of fresh air into the engine. The initial intake pressure sensor 8 and the initial intake temperature sensor 9 are installed on the initial intake main pipe 10, used to monitor the initial intake pressure and temperature data, and feedback the data to the ECU control system in real time;

[0102] In this embodiment, the outlet of the compressor 7 is connected to the intake air intercooler 13, and a boost pressure sensor 12 is installed on the compressor outlet pipeline, used to monitor the boost pressure of the gas at the compressor outlet. The intake air intercooler 13 is responsible for cooling the boosted fresh air;

[0103] In this embodiment, the fresh air cooled by the intake air intercooler 13 flows towards the throttle valve 14. The throttle valve 14 is connected to the ECU control system 1 and adjusts its opening degree under the ECU command, thereby realizing the controllable adjustment of the fresh air intake flow rate;

[0104] In this embodiment, the EGR intake air and the supercharged fresh air intake air are mixed in the intake air mixer 17. The mixed gas flows into the engine through the intake manifold 16. The TMAP sensor 15 is installed on the intake manifold 16 to monitor the total engine intake air flow rate and feedback the flow rate information to the ECU control system;

[0105] In this embodiment, the ECU control system 1 is an engine electronic control unit, which can collect and process various signal data from engine sensors, including but not limited to the signals of the aforementioned sensor components, and control the actions of the actuators according to the preset control logic and calibration data to ensure the stable operation of the engine.

[0106] In another specific embodiment, as Figure 6 shown, the process includes:

[0107] S101, obtain the current initial intake air pressure value P1 and the supercharged fresh air intake air pressure value P2 of the engine through the initial intake air pressure sensor and the supercharging pressure sensor, and calculate the pressure ratio value α of the compressor of the current engine turbocharger using the pressure ratio equation. The pressure ratio calculation equation is as follows (where the values of P1 and P2 are both absolute pressures, and absolute pressure = indicated pressure + atmospheric pressure):

[0108] S102, obtain the current turbocharger speed value R1 of the engine through the turbocharger speed sensor. Using the aforementioned supercharging pressure ratio value α, the turbocharger speed R1, and the MAP of the compressor of the turbocharger, the initial fresh air volume L1 flowing through the compressor can be calculated. Among them, the MAP of the compressor of the turbocharger is a MAP chart pre-calibrated during the design of the supercharger and includes multiple historical speeds, multiple historical supercharging pressure ratios, and the historical intake air volumes corresponding to each of the above historical speeds and the above historical pressure ratios.

[0109] In this embodiment, the exhaust gas discharged from the engine flows into the turbine of the turbocharger through the exhaust manifold, driving the rotation of the turbine blades. The turbine and the compressor are coaxially connected. The rotation of the turbine blades drives the rotation of the compressor. The blades of the compressor usually adopt an airfoil design and have a twist angle, which can convert kinetic energy into the pressure energy of fresh air, complete the compression of fresh air, and increase the pressure and density of the initial fresh air. When designing and manufacturing the compressor of the turbocharger, a MAP chart including flow rate, rotational speed, and boost pressure ratio is pre-designed, and the performance calibration is completed through means such as experimental calibration or simulation, obtaining a one-to-one mapping relationship. Finally, a performance MAP chart including multiple historical rotational speeds, multiple historical boost pressure ratios, and the historical intake air volume corresponding to each of the above historical rotational speeds and historical pressure ratios is formed. Therefore, after obtaining the current turbocharger rotational speed value R1 and the current boost pressure value α, the corresponding current fresh air intake flow rate value L1 can be determined through the above mapping relationship.

[0110] S103. Obtain the current initial intake air temperature value T1 of the engine through the initial intake air temperature sensor of the engine, obtain the corresponding initial temperature correction coefficient K1 through the pre-set temperature correction coefficient chart, and calculate the product of the initial temperature correction coefficient K1 and the above initial fresh air volume L1 to obtain the corrected fresh air intake volume L2.

[0111] In this embodiment, step S103 can be implemented through the following steps, as Figure 7 shown, step S201: The initial intake air temperature is the temperature of the fresh air before entering the compressor. Different initial intake air temperatures will affect the intake air flow rate of the fresh air. The initial fresh air volume L1 is corrected through the temperature correction coefficient. The intake air volume of the fresh air at each initial intake air temperature can be calibrated in advance through means such as experimental calibration or simulation to obtain a temperature correction coefficient chart with a one-to-one mapping relationship; as Figure 8 shown, step S202: After determining the engine initial intake air temperature value T1, obtain the current initial temperature correction coefficient K1 by looking up the table, and then calculate the product of the temperature correction coefficient K1 and the above initial fresh air volume L1 to obtain the corrected fresh air intake volume L2.

[0112] S104. The intake air temperature value T2 and the intake air pressure value P3 of the current engine intake manifold 16 can be obtained through the engine intake manifold TMAP sensor, and the intake air temperature and intake air pressure monitoring values are fed back to the ECU control system 1 in real time. The ECU can calculate the total air volume L0 currently entering the engine.

[0113] In this embodiment, the above step S104 can be implemented through the following steps, as Figure 9As shown, step S203: The absolute pressure and intake air temperature value in the intake manifold 16 can be measured in real time through the TMAP sensor. Combining with the ideal gas state equation PV = nRT, the air density in the intake manifold 16 is calculated. ρ = m / V, where n = m / M (M is the molar mass of air), and it can be deduced that ρ = PM / (RT), that is, the air density is proportional to the intake pressure and inversely proportional to the intake temperature;

[0114] In this embodiment, according to the displacement of the engine, the real-time engine speed, and the air density in the intake manifold 16 calculated above, the ECU control system calculates the mass air flow rate L0 entering the engine. Among them, the specific formula is the intake air flow Q = ρVη, where ρ is the intake air density calculated above, V is the intake volume of the engine per unit time, which is related to the engine displacement and speed, and η is the intake efficiency, which is the percentage of the actual air volume inhaled by the engine to its theoretical maximum inhalation volume. The ECU can accurately calculate the engine intake efficiency by collecting the above TMAP sensor values, throttle opening values, and engine speed and torque values through a pre-set internal calculation model and algorithm. The calculation model and algorithm for the ECU to calculate the intake efficiency internally can be obtained through experimental calibration or simulation means, which is not within the scope of the introduction of the present invention and will not be elaborated here.

[0115] In this embodiment, through step S104, the total air volume L0 entering the engine through the intake mixer 17 can be obtained according to the TMAP sensor 15 of the intake manifold 16;

[0116] S105, according to the above corrected fresh air intake volume L2 and the total air volume L0 entering the engine, calculate the difference between the total air volume L0 entering the engine and the corrected fresh air intake volume L2, and finally obtain the accurate EGR intake air flow rate L3.

[0117] In another specific embodiment, as Figure 10 described in the system, it can be used to execute the calculation method of the EGR intake air flow rate. It includes: a signal acquisition unit A10, a signal determination unit A20, a first calculation unit A30, a second calculation unit A40, and a signal output unit A50.

[0118] Among them, the signal acquisition unit A10 is used to acquire the initial intake pressure, initial intake temperature, turbocharger speed, post-boost air pressure, and TMAP sensor signal of the engine, and transmit the signal values to the ECU control system 1 in real time;

[0119] The signal determination unit A20 is used to confirm the current engine speed, fuel injection quantity, throttle opening, EGR valve opening, and Norgren valve opening values in real time to determine the current engine operating state;

[0120] The first signal calculation unit A30 is used, on the one hand, to calculate the ratio of the supercharged air pressure to the initial intake air pressure, determine the pressure ratio α of the compressor of the turbocharger, read the turbocharger speed value R1, query the compressor performance MAP chart using the pressure ratio value α and the turbocharger speed value R1, and calculate the initial fresh air volume L1 flowing through the compressor;

[0121] In this embodiment, the compressor performance MAP is a MAP chart pre-calibrated during the design of the supercharger and containing multiple historical speeds, multiple historical pressure ratios, and the historical intake air volumes corresponding to each of the above historical speeds and historical pressure ratios, and is pre-stored in the first calculation unit A30;

[0122] The first signal unit A30 is used, on the other hand, to obtain the initial intake air temperature T1, query the temperature correction coefficient chart, determine the temperature correction coefficient corresponding to the initial intake air temperature, obtain the initial temperature correction coefficient K1, and calculate the product of the initial temperature correction coefficient K1 and the above initial fresh air volume L1 to obtain the corrected fresh air intake volume L2;

[0123] In this embodiment, the temperature correction coefficient chart is a pre-calibrated chart containing multiple historical temperatures and the temperature correction coefficients corresponding to each of the above historical temperatures. The calibration of the chart data can be completed by means of experimental calibration or simulation, and is stored in the first calculation unit A30;

[0124] The second calculation unit A40 is used to obtain the intake manifold TMAP sensor signal values, including the intake air temperature and intake air pressure values, and calculate the total air volume entering the engine using the foregoing step S203 to obtain the current total air volume L0 entering the engine;

[0125] The signal output unit A50 is used to obtain the above corrected fresh air intake volume and the total air volume L0 entering the engine, calculate the difference between the total air volume L0 entering the engine and the corrected fresh air intake volume L2, and obtain the accurate EGR intake flow rate L3.

[0126] Figure 11 It is a block diagram of an electronic device structure for a vehicle power system control method provided by one or more embodiments of the present invention.

[0127] As Figure 11 shown, the present application provides an electronic device, including: a processor, a communication interface, a memory, and a communication bus. Among them, the processor, the communication interface, and the memory complete mutual communication through the communication bus;

[0128] A computer program is stored in the memory. When the computer program is executed by the processor, the processor executes the steps of the EGR intake flow rate calculation method.

[0129] The present application also provides a computer-readable storage medium, which stores steps for implementing the EGR intake air flow calculation method executable by an electronic device.

[0130] The present application also provides a vehicle, comprising:

[0131] An electronic device for implementing the steps of the EGR intake air flow calculation method;

[0132] A processor that runs a program, and when the program runs, executes the steps of the EGR intake air flow calculation method on the data output from the electronic device;

[0133] A storage medium for storing a program, and when the program runs, executes the steps of the EGR intake air flow calculation method on the data output from the electronic device.

[0134] From the description of the above embodiments, those skilled in the art can clearly understand that the present application can be implemented by means of software plus a necessary general hardware platform. Based on such an understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a storage medium, such as ROM / RAM, magnetic disk, optical disc, etc., and includes several instructions for causing a computer device (which can be a personal computer, server, or network device, etc.) to execute the methods described in various embodiments or some parts of the embodiments of the present application.

[0135] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A turbocharged engine, characterized in that, The engine includes: an engine body, a turbocharger, an EGR intercooler, an EGR valve, an intake air intercooler, a throttle valve, an intake air mixer, and sensors; The engine body is used as the place for engine intake, exhaust, and combustion; The turbocharger is used to increase the engine intake air volume; The EGR intercooler is used to cool the EGR high-temperature gas; The EGR valve is used to regulate the EGR gas flow rate; The intake air intercooler is used to cool the fresh air compressed by the compressor; The throttle valve is used to regulate the fresh air intake volume; The intake air mixer is used for the mixing of the EGR gas and the fresh air; The sensors are used to collect the status information of the engine; Among them, the sensors include an initial intake air pressure sensor, an initial intake air temperature sensor, a turbocharger speed sensor, a boost pressure sensor, an intake manifold TMAP sensor, and an engine speed sensor; It also includes an ECU control system for receiving the sensor signal values; Among them, pre-stored calibration data is obtained; The ECU control system controls the engine to operate in a preset operating state according to the calibration data and the sensor signal values; Controlling the engine to operate in a preset operating state includes that the ECU control system regulates the opening degrees of the Norgren valve, the throttle valve, and the EGR valve.

2. An EGR intake air flow calculation system, characterized in that, The EGR intake air flow calculation system includes: a signal acquisition unit, a signal determination unit, a first calculation unit, a second calculation unit, and a signal output unit; The signal acquisition unit is used to acquire the sensor signal values of the engine and transmit them to the ECU control system in real time; The signal determination unit is used to determine the engine operating state; The first calculation unit is used to obtain the initial fresh air volume L1 flowing through the compressor and the corrected fresh air intake volume L2; The second calculation unit is used to obtain the total air volume L0 entering the engine; The signal output unit is used to calculate the difference between the total air volume L0 entering the engine and the corrected fresh air intake volume L2 to obtain the EGR intake air flow L3.

3. A method for calculating the EGR intake air flow rate, characterized in that, The EGR intake air flow calculation method includes: Collecting the sensor signal values; Obtaining the engine status data according to the sensor signal values; Among them, the engine status data includes the initial intake air pressure value P1 and the air pressure value P2 after supercharging; According to the formula Obtain the supercharging pressure ratio α of the front engine turbocharger.

4. The EGR intake air flow calculation method according to claim 3, wherein The engine status data also includes: the engine turbocharger speed value R1; Obtaining the turbocharger compressor performance MAP table; According to the boost pressure ratio α, the turbocharger speed R1, and the turbocharger compressor performance MAP table, obtaining the initial fresh air volume L1 flowing through the compressor; 5. The EGR intake air flow calculation method according to claim 4, wherein The engine status data also includes the engine initial intake air temperature value T1; Obtaining the temperature correction coefficient chart; According to the temperature correction coefficient chart and the initial intake air temperature value T1, obtaining the corresponding initial temperature correction coefficient K1; Calculating the product of the initial intake air temperature correction coefficient K1 and the above initial fresh air volume L1 to obtain the corrected fresh air intake volume L2.

6. The EGR intake air flow calculation method according to claim 5, wherein The engine status data also includes: the intake air temperature T2 and the intake air pressure P3 of the engine intake manifold; According to the intake air temperature T2 and the intake air pressure P3 of the engine intake manifold, obtaining the total air volume L0 entering the engine; Based on the corrected fresh air intake L2 and the total air intake L0 into the engine, obtain the difference between the total air intake L0 into the engine and the corrected fresh air intake L2; Based on the difference between the total air intake L0 into the engine and the corrected fresh air intake L2, obtain the EGR intake flow rate L3.

7. An EGR intake air flow calculation device, characterized in that, The EGR intake flow rate calculation device includes: A signal acquisition module for acquiring sensor signal values; An engine status module for obtaining engine status data according to the sensor signal values; Among them, the engine status data includes the initial intake pressure value P1 and the supercharged air pressure value P2; An algorithm module for obtaining the supercharging pressure ratio α of the front engine turbocharger according to the formula ​ 8. An electronic device, characterized in that, Includes: A processor, a communication interface, a memory, and a communication bus. Among them, the processor, the communication interface, and the memory complete mutual communication through the communication bus; The memory stores a computer program. When the computer program is executed by the processor, the processor executes the steps of the EGR intake flow rate calculation method described in any one of claims 3 to 6.

9. A computer-readable storage medium, characterized in that, It stores a computer program executable by an electronic device. When the computer program runs on the electronic device, the electronic device executes the steps of the EGR intake flow rate calculation method described in any one of claims 3 to 6.

10. A vehicle, characterized in that, Includes: An electronic device for implementing the steps of the EGR intake flow rate calculation method described in any one of claims 3 to 6; A processor. The processor runs a program. When the program runs, it executes the steps of the EGR intake flow rate calculation method described in any one of claims 3 to 6 on the data output from the electronic device; A storage medium for storing a program. When the program runs, it executes the steps of the EGR intake flow rate calculation method described in any one of claims 3 to 6 on the data output from the electronic device.

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