Control method and system of engine waste gas treatment system, vehicle and storage medium

Abstract

The invention provides a control method and system of an engine waste gas treatment system, a vehicle and a storage medium. The engine waste gas treatment system comprises a mixer and a valve device arranged on the upstream of the mixer, waste gas discharged by an engine flows into the mixer through the valve device, the valve device is used for controlling the gas inlet area of a gas inlet of the mixer, and the mixer is used for mixing a waste gas reducing agent and the waste gas discharged by the engine. When the engine is in different load working conditions, the airflow velocity when waste gas flows into the mixer is controlled by controlling the opening value of the valve device. Therefore, the waste gas and the waste gas reducing agent at different flow speeds are mixed in the mixer. Namely, the opening value of the valve device can be adaptively controlled based on the load working condition of the engine so as to control the airflow velocity when the waste gas flows into the mixer, and mixing of the waste gas and the waste gas reducing agent is affected at the proper airflow velocity. Therefore, catalytic reduction reaction between the waste gas and the waste gas reducing agent is promoted, and emission of the waste gas is reduced.

Description

Technical Field

[0001] The present application relates to the field of vehicles, and more particularly, to a control method, a system, a vehicle and a storage medium of an engine exhaust treatment system in the field of vehicles. Background Art

[0002] In recent years, in order to cope with global warming and the intensification of the greenhouse effect, countries have put forward higher requirements for the limits of vehicle emission pollutants. At present, urea selective catalytic reduction technology is usually applied in the exhaust after-treatment system of the engine. Specifically, a mixing chamber is installed after the urea nozzle of the exhaust after-treatment system, and the air flow disturbance in the exhaust after-treatment system is improved by adding fins, porous tubes, baffles and other combinations to promote the uniformity of urea flow, so that the urea aqueous solution and the exhaust gas in the exhaust after-treatment system are fully mixed, thereby reducing the exhaust gas emissions.

[0003] However, the above process will have the following problems: when the engine is working at low load, the mass flow rate of the exhaust gas discharged by the engine is small and the flow rate is low. This will cause insufficient air flow disturbance in the exhaust aftertreatment system, low efficiency of urea hydrolysis and pyrolysis reaction, and uneven mixing of urea aqueous solution and exhaust gas. This will cause the urea aqueous solution to form crystals on the inner wall of the exhaust pipe in the exhaust aftertreatment system, generating a large amount of sediment, thereby affecting the operation of the catalytic reduction reaction and the conversion efficiency of nitrogen oxides, that is, causing a large amount of exhaust gas emissions. Summary of the invention

[0004] The present application provides a control method, system, vehicle and storage medium for an engine exhaust treatment system. The method can control the airflow velocity of the exhaust gas when it flows into the mixer by controlling the opening value of the valve device regardless of the load condition of the engine, thereby uniformly mixing the exhaust gas and the exhaust gas reducing agent at an appropriate airflow velocity, promoting the catalytic reduction reaction between the exhaust gas and the exhaust gas reducing agent, improving the conversion efficiency of nitrogen oxides, and reducing the emission of exhaust gas (for example, vehicle exhaust).

[0005] In a first aspect, a control method for an engine exhaust treatment system is provided, the engine exhaust treatment system comprising a mixer and a valve device arranged upstream of the mixer, the engine exhaust treatment system is connected to the engine through the valve device, exhaust gas emitted by the engine flows into the mixer through the valve device, the valve device is used to control the intake area of ​​the intake port of the mixer, the mixer is used to mix exhaust gas reductant and exhaust gas emitted by the engine, the method comprising: determining the load condition of the engine; determining the opening value of the valve device based on the load condition; controlling the valve device to open to the opening value, so as to control the exhaust gas emitted by the engine to flow into the mixer through the intake port.

[0006] In the above technical scheme, the present application proposes a control method for an engine exhaust treatment system, the engine exhaust treatment system includes a mixer and a valve device arranged upstream of the mixer, wherein the engine exhaust treatment system is connected to the engine through the valve device, the exhaust gas discharged by the engine flows into the mixer through the valve device, the valve device is used to control the intake area of ​​the air inlet of the mixer, and the mixer is used to mix the exhaust gas reducing agent and the exhaust gas discharged by the engine. The present application can control the air flow rate when the exhaust gas discharged by the engine flows into the mixer (the air inlet of the mixer) by controlling the opening value of the valve device when the engine is in different load conditions. Thereby, the exhaust gas and the exhaust gas reducing agent at different flow rates are mixed in the mixer. That is to say, the opening value of the valve device can be adaptively controlled based on the load condition of the engine to adaptively control the air flow rate when the exhaust gas flows into the mixer (the air flow disturbance in the mixer). This can make the exhaust gas and the exhaust gas reducing agent mix evenly with appropriate airflow disturbance, thereby promoting the catalytic reduction reaction between the exhaust gas and the exhaust gas reducing agent, improving the conversion efficiency of nitrogen oxides, and reducing the emission of exhaust gas (for example, vehicle exhaust).

[0007] In combination with the first aspect, in certain possible implementations, determining the load condition of the engine includes: obtaining the mass flow rate of air flowing into the engine through the air flow meter, the air flow meter is connected to the engine, and the mass flow rate is used to characterize the load of the engine; determining the mass flow rate range in which the mass flow rate is located; and determining the load condition of the engine based on the mass flow rate range.

[0008] In the above technical solution, the air flow meter is used to detect the intake air volume per unit time of the engine, that is, the mass flow rate of the air. Since the load condition of the engine is limited by the fuel supply (the amount of fuel provided) or the intake air volume, the mass flow rate of the air can be used to determine the load condition of the engine. Specifically, the load condition of the engine is determined based on the mass flow rate range of the mass flow rate of the air.

[0009] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, determining the load condition of the engine includes: obtaining the speed of the engine through a speed sensor connected to the engine, and obtaining the opening angle of the throttle through a throttle position sensor arranged on the throttle, the throttle being connected to the engine and used to control the mass flow rate of air flowing into the engine; determining the load of the engine based on the speed and the opening angle of the throttle; and determining the load condition of the engine based on the load range in which the load is located.

[0010] In the above technical solution, when the engine is running at a fixed speed, the opening angle of the throttle valve will affect the amount of air flowing into the engine per unit time (that is, the mass flow rate of air), and thus affect the load borne by the engine during operation, the load range, and the load condition. Therefore, the load condition of the engine can be comprehensively determined based on the engine speed and the opening angle of the throttle valve.

[0011] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, the opening value of the valve device is determined based on the load condition, including: when the load condition is a first condition, the first opening value is determined as the opening value; when the load condition is a second condition, the second opening value is determined as the opening value; when the load condition is a third condition, the third opening value is determined as the opening value; wherein, the load corresponding to the first condition is smaller than the load corresponding to the second condition, the load corresponding to the second condition is smaller than the load corresponding to the third condition, the first opening value is smaller than the second opening value, and the second opening value is smaller than the third opening value.

[0012] In the above technical solution, different opening values ​​of the corresponding valve device are described when the load condition is specifically different load conditions. In some embodiments, the first condition is a small load condition, the second condition is a medium load condition, and the third condition is a large load condition or a full load condition. Correspondingly, the first opening value under the small load condition is smaller than the second opening value under the medium load condition, and the second opening value under the medium load condition is smaller than the third opening value under the large load condition or the full load condition. This is due to the following reasons: the smaller the load corresponding to the load condition, the smaller the airflow velocity when the exhaust gas discharged by the engine flows into the mixer (the air inlet of the mixer). This will cause the airflow disturbance in the mixer in the engine exhaust treatment system to be less sufficient, resulting in more uneven mixing of the exhaust gas reductant and the exhaust gas. In this regard, the smaller the load corresponding to the load condition, the more it is necessary to increase the airflow disturbance in the mixer, the more it is necessary to reduce the air intake area of ​​the air inlet of the mixer, and the more it is necessary to reduce the opening value of the valve device. Among them, when the mass flow rate of air is fixed, the smaller the intake area of ​​the air inlet of the mixer, the greater the air flow velocity when the exhaust gas flows into the mixer (the air inlet of the mixer), and the more complete the air flow disturbance in the mixer.

[0013] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, the valve device includes a rotating valve stem and a valve, the rotating valve stem is connected to the valve, the valve includes any one of a ball valve, a gate valve, a stop valve, a butterfly valve and a regulating valve, and controlling the valve device to open to the opening value includes: controlling the rotating valve stem to rotate to control the valve to open to the opening value.

[0014] In the above technical solution, the valve device is described as including a rotating valve stem and a valve, and the rotating valve stem is connected to the valve. When the valve includes any one of a ball valve, a gate valve, a stop valve, a butterfly valve and a regulating valve, the rotation of the rotating valve stem can be controlled to drive the valve to rotate, so as to control the process of opening the valve to the opening value.

[0015] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, the method also includes: obtaining the driving speed of the vehicle including the engine exhaust treatment system; and, based on the load condition, determining the opening value of the valve device, including: determining the opening value of the valve device based on the driving speed and the load condition.

[0016] In the above technical solution, under different vehicle speeds and different load conditions, the intake pressure and intake density of the engine are different, and the air flow disturbance in the mixer is different. Under different air flow disturbances, the mixing degree of the exhaust gas reducing agent and the exhaust gas is different. In order to fully mix the exhaust gas reducing agent and the exhaust gas, the degree of air flow disturbance in the mixer can be appropriately controlled by adjusting the opening value of the valve device. Specifically, the opening value of the valve device is adjusted based on the driving speed and the load condition.

[0017] In a second aspect, an engine exhaust treatment system is provided, which includes a target controller, a mixer and a valve device, wherein the engine exhaust treatment system is connected to the engine via the valve device; the valve device is connected to the mixer and is arranged upstream of the mixer, and is used to control the intake area of ​​the intake port of the mixer, and the exhaust gas emitted by the engine flows into the mixer through the valve device; the target controller is connected to the valve device, and is used to control the opening value of the valve device based on the load condition of the engine; the mixer is used to mix the exhaust reductant and the exhaust gas emitted by the engine.

[0018] In combination with the second aspect, in some possible implementations, the target controller is connected to an air flow meter, which is connected to the engine. The target controller is also used to: obtain the mass flow rate of air flowing into the engine through the air flow meter; and determine the load condition of the engine based on the mass flow rate.

[0019] In a third aspect, a vehicle is provided, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, wherein when the processor executes the computer program, a target controller in the vehicle executes the method in the above-mentioned first aspect or any possible implementation of the first aspect.

[0020] In a fourth aspect, a computer-readable storage medium is provided, which stores instructions. When the instructions are executed on a computer or a processor, the computer or the processor executes the method in the first aspect or any possible implementation of the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of an existing engine intake and exhaust system provided in an embodiment of the present application;

[0022] Figure 2 It is a structural schematic diagram of an engine intake and exhaust system provided in an embodiment of the present application;

[0023] Figure 3 is a schematic flow chart of a control method of an engine exhaust treatment system provided in an embodiment of the present application;

[0024] Figure 4 It is a schematic diagram of the structure of a valve device provided in an embodiment of the present application;

[0025] Figure 5 is a schematic structural diagram of a control device for an engine exhaust gas treatment system provided in an embodiment of the present application;

[0026] Figure 6 is a structural schematic diagram of an engine exhaust gas treatment system provided in an embodiment of the present application;

[0027] Figure 7 is a structural schematic diagram of another engine exhaust treatment system provided in an embodiment of the present application;

[0028] Figure 8 It is a structural schematic diagram of a vehicle provided in an embodiment of the present application. DETAILED DESCRIPTION

[0029] The technical solutions in the present application will be described clearly and in detail below in conjunction with the accompanying drawings. In the description of the embodiments of the present application, "multiple" means two or more than two. The terms "first" and "second" are used for descriptive purposes only and should not be understood as implying or suggesting relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0030] Figure 1 It is a structural schematic diagram of an existing engine intake and exhaust system provided in an embodiment of the present application.

[0031] For example, Figure 1As shown in (a) of FIG. 1 , the engine intake and exhaust system includes an air management module 101, a compressor 102, an intercooler module 103, an engine 104, a turbine 105, a post-processing module 106, and a muffler module 107. The compressor 102 is connected to the air management module 101, the intercooler module 103 and the turbine 105 are connected to the compressor 102, respectively, the engine 104 is connected to the intercooler module 103, the turbine 105 is connected to the engine 104, the post-processing module 106 is connected to the turbine 105, the muffler module 107 is connected to the post-processing module 106, and the compressor 102 and the turbine 105 are combined into a whole through the same shaft, which is called a turbocharger.

[0032] Specifically, the outside air is filtered through the air management module 101 to obtain purified clean air. After the clean air is pressurized by the compressor 102, it passes through the intercooler and heat dissipation module 103 to obtain clean air after cooling. After the clean air after cooling is burned in the engine 104, the engine 104 discharges exhaust gas. After the exhaust gas is pressurized by the turbine 105, it can not only allow the supercharged exhaust gas to enter the post-processing module 106, but also drive the compressor 102 on the same axis to rotate, so that more outside air is sucked into the air management module 101 through the rotation of the compressor 102, thereby increasing the air intake of the engine 104. The post-processing module 106 processes the exhaust gas to obtain gas with the least pollution to the external environment as much as possible. Finally, the gas is discharged into the external environment through the muffler module 107. Among them, the muffler module 107 is used to reduce the noise generated when the engine is working.

[0033] Among them, specifically Figure 1 As shown in (b) , the air management module 101 includes an air filter 1011 and an air flow meter 1012 , and the air flow meter 1012 is connected to the air filter 1011 .

[0034] Among them, specifically Figure 1 As shown in (c) in the figure, the post-processing module 106 includes an oxidation catalytic converter 1061, a particulate trap 1062, a mixer 1064, an exhaust gas reductant injection device 1063 and a catalytic reduction device 1065. The particulate trap 1062 is connected to the oxidation catalytic converter 1061, the mixer 1064 is connected to the particulate trap 1062, and the exhaust gas reductant injection device 1063 and the catalytic reduction device 1065 are respectively connected to the mixer 1064.

[0035] Furthermore, the air management module 101 filters the outside air through the air filter 1011 to obtain purified clean air. The air flow meter 1012 detects the clean air flowing into the engine 104 (first flowing into the compressor 102, then flowing into the intercooler module 103, and finally flowing into the engine 104) to obtain the mass flow of the clean air, so as to determine the amount of fuel injected into the engine 104 based on the mass flow.

[0036] Furthermore, the post-processing module 106 purifies carbon monoxide and hydrocarbons in the exhaust gas through the catalyst in the oxidation catalytic converter 1061; and captures particulate matter in the exhaust gas through the particulate collector 1062. Afterwards, the exhaust gas that has been purified and captured flows into the mixer 1064, and at the same time, the exhaust gas reductant injection device 1063 injects the exhaust gas reductant into the mixer 1064. Since the mixer 1064 includes components in various combinations such as fins, porous tubes, and baffles that can increase airflow disturbance, the mixer 1064 can promote the flow uniformity of the exhaust gas reductant, so that the exhaust gas reductant is fully mixed with the exhaust gas that has been purified and captured. Finally, in the catalytic reduction device 1065, the exhaust gas reductant undergoes a catalytic reduction reaction with the exhaust gas that has been purified and captured.

[0037] It should be understood that the exhaust gas reductant injection device 1063 can inject exhaust gas reductant into the mixer 1064 at a determined start-up time, a determined injection amount and a determined injection duration based on the real-time operating conditions of the engine, thereby providing exhaust gas reductant for the catalytic reduction reaction of nitrogen oxides.

[0038] In some embodiments, the exhaust gas reducing agent injection device 1063 in the above solution is a urea injection device 1063, and correspondingly, the exhaust gas reducing agent is a urea aqueous solution.

[0039] However, the above process has the following problems: when the engine 104 is working under a low load condition, the mass flow rate of the exhaust gas discharged by the engine 104 is small. This will cause the exhaust gas to flow into the mixer 1064 at a low flow rate, resulting in insufficient air flow disturbance in the mixer 1064, resulting in uneven mixing of the exhaust gas reductant and the exhaust gas. In some embodiments, the exhaust gas reductant is a urea aqueous solution. When the urea aqueous solution is unevenly mixed with the exhaust gas, crystals will form on the inner wall of the exhaust gas exhaust pipe (for example, the inner wall of the catalytic reduction device 1065), affecting the operation of the selective catalytic reduction reaction (Selective Catalytic Reduction, SCR), affecting the conversion efficiency of nitrogen oxides, and causing a large amount of exhaust gas emissions.

[0040] In order to solve the above problems, the method proposed in this application is Figure 1A valve device 1066 is added between the particle collector 1062 and the mixer 1064 in (c), as shown in FIG. Figure 2 As shown, the valve device ensures that the exhaust gas flows into the mixer 1064 at a required air flow rate by controlling the air intake area of ​​the air intake port of the mixer 1064, so that the air flow disturbance in the mixer 1064 is sufficient, so that the exhaust gas reductant and the exhaust gas are evenly mixed, and then the exhaust gas reductant and the exhaust gas fully react to reduce the emission of the exhaust gas.

[0041] A control method for an engine exhaust treatment system proposed in the present application is described below with a specific embodiment.

[0042] Figure 3 It is a schematic flow chart of a control method of an engine exhaust treatment system provided in an embodiment of the present application.

[0043] The engine exhaust treatment system mentioned above includes a mixer and a valve device arranged upstream of the mixer. The engine exhaust treatment system is connected to the engine through the valve device. The exhaust gas emitted by the engine flows into the mixer through the valve device. The valve device is used to control the intake area of ​​the air inlet of the mixer. The mixer is used to mix the exhaust gas reductant and the exhaust gas emitted by the engine.

[0044] It should be understood that the engine in the present application may be a diesel engine.

[0045] It should also be understood that a control method for an engine exhaust treatment system provided in an embodiment of the present application can be applied to a target controller, which is a vehicle controller in a vehicle including the engine exhaust treatment system or a controller in the engine exhaust treatment system.

[0046] For example, Figure 3 As shown, the method 300 includes:

[0047] Step 301: The vehicle controller determines the load condition of the engine.

[0048] It should be understood that the "load condition" in the above step 301 refers to the condition in which the engine is running, measured by the load of the engine. "Load" refers to the load borne by the engine during operation, which is simply understood as the size of the external force resistance to the engine. In some embodiments, the load condition includes a small load condition, a medium load condition and a large load condition (or a full load condition). Specifically, when the engine is in a small load condition, the load of the engine is in a first load range (n1, n2); when the engine is in a medium load condition, the load of the engine is in a second load range (n3, n4); when the engine is in a large load condition, the load of the engine is in a third load range (n5, n6). Among them, n3≥n2, n5≥n4.

[0049] In some embodiments, when the engine is in a light load condition, the first load range is (0, 0.25); when the engine is in a medium load condition, the second load range is (0.25, 0.85); when the engine is in a heavy load condition, the third load range is (0.85, 1).

[0050] The load condition of the engine is determined in three ways as follows.

[0051] The first

[0052] In one possible implementation, step 301 includes: the vehicle controller obtains the speed of the engine through a speed sensor connected to the engine, and obtains the opening angle of the throttle through a throttle position sensor arranged on the throttle, the throttle is connected to the engine and is used to control the mass flow rate of air flowing into the engine; the vehicle controller determines the load of the engine based on the speed and the opening angle of the throttle; the vehicle controller determines the load condition of the engine based on the load range of the load.

[0053] It should be understood that when the engine is running at a fixed speed, the opening angle of the throttle valve will affect the mass flow of air flowing into the engine. Furthermore, the vehicle controller can determine the load condition of the engine by the mass flow of air flowing into the engine. Therefore, the vehicle controller can comprehensively determine the load condition of the engine based on the engine speed and the opening angle of the throttle valve.

[0054] In the above technical solution, when the engine is running at a fixed speed, the opening angle of the throttle valve will affect the amount of air that flows into the engine per unit time (that is, the mass flow rate of air), and thus affect the load borne by the engine during operation, the load range of the load, and the load condition. Therefore, the load condition of the engine can be accurately determined based on the engine speed and the opening angle of the throttle valve.

[0055] In some embodiments, the vehicle controller determines the load of the engine based on the speed and the opening angle of the throttle, including: when the speed is in a first speed range, the vehicle controller determines the load based on the product of the opening angle and a first factor; when the speed is in a second speed range, the vehicle controller determines the load based on the product of the opening angle and a second factor, the speed corresponding to the second speed range is greater than the speed corresponding to the first speed, and the second factor is greater than the first factor.

[0056] Exemplarily, the vehicle controller determines that the load of the engine is 0.5 based on the engine speed and the throttle opening angle; the vehicle controller determines that the load range of the load 0.5 is the second load range; based on the second load range, the vehicle controller determines that the load condition of the engine is a medium load condition.

[0057] The second

[0058] In one possible implementation, step 301 includes: the vehicle controller obtains the mass flow rate of air flowing into the engine through the air flow meter, the air flow meter is connected to the engine, and the mass flow rate is used to characterize the load of the engine; the vehicle controller determines the mass flow rate range of the mass flow rate; the vehicle controller determines the load condition of the engine based on the mass flow rate range.

[0059] It should be understood that when the engine is running, the mass flow rate of air flowing into the engine will affect the air resistance encountered by the engine during operation and the load borne by the engine. Specifically, the greater the mass flow rate of air, the greater the air resistance encountered by the engine during operation, the greater the load borne by the engine, and the greater the load on the engine. Furthermore, since the load condition refers to the condition in which the engine is running measured by the load of the engine, the vehicle controller can determine the load condition of the engine by the mass flow rate of air flowing into the engine.

[0060] In some embodiments, the vehicle controller determines the mass flow range in which the mass flow is located, including: the vehicle controller compares the mass flow with multiple candidate mass flow ranges; the vehicle controller determines the mass flow range that matches the mass flow from the multiple candidate mass flow ranges.

[0061] In some embodiments, the plurality of candidate mass flow ranges include a first mass flow range, a second mass flow range, and a third mass flow range. When the mass flow of air is in the first mass flow range (m1, m2), the load condition of the engine is a light load condition; when the mass flow of air is in the second mass flow range (m3, m4), the load condition of the engine is a medium load condition; when the mass flow of air is in the third mass flow range (m5, m6), the load condition of the engine is a heavy load condition. Wherein, m3≥m2, m5≥m4.

[0062] In the above technical solution, the air flow meter is used to detect the intake air volume per unit time of the engine, that is, the mass flow rate of the air. Since the load condition of the engine is limited by the fuel supply (the amount of fuel provided) or the intake air volume, the mass flow rate of the air can be used to determine the load condition of the engine. Specifically, the load condition of the engine is determined based on the mass flow rate range of the mass flow rate of the air.

[0063] The third

[0064] In some embodiments, step 301 includes: the vehicle controller obtains the torque of the engine through a torque sensor connected to the engine, and obtains the speed of the engine through the speed sensor; the vehicle controller determines the power of the engine through the torque and the speed, and the power is used to characterize the load of the engine; the vehicle controller determines the power range of the power; the vehicle controller determines the load condition of the engine based on the power range.

[0065] Specifically, the vehicle controller determines the power of the engine through the torque and the speed, including: the vehicle controller determines the power of the engine through the following formula (1);

[0066] P = 2π*N*M / 60;

[0067] Where P is the power of the engine, in kW; N is the torque, in N·m; M is the speed, in rpm / min. “M / 60” is used to convert the speed to rpm / s. The power in formula (1) is used to represent the work done by the engine per rotation.

[0068] It should be understood that the power of the engine is closely related to the load of the engine. Generally, under a smaller load, the power of the engine is lower; under a larger load, the power of the engine is higher.

[0069] In some embodiments, when the engine power is in the first power range (p1, p2), the load condition of the engine is a light load condition; when the engine power is in the second power range (p3, p4), the load condition of the engine is a medium load condition; when the engine power is in the third power range (p5, p6), the load condition of the engine is a heavy load condition. Wherein, p3≥p2, p5≥p4.

[0070] In the above technical solution, the power of the engine can be determined more quickly and accurately through formula (1), thereby determining the power range of the power, and then based on the power range, determining the load condition of the engine more quickly and accurately.

[0071] It should be understood that the above-mentioned three methods are used to determine the load condition of the engine. The first method is to comprehensively determine the load of the engine by the engine speed and the opening angle of the engine throttle, thereby directly determining the load condition of the engine by the load range in which the load is located; the second method is to indirectly determine the load condition of the engine by the mass flow range of the mass flow of the air flowing into the engine; the third method is to indirectly determine the load condition of the engine by the power range in which the engine power is located. Among them, since the mass flow rate of the air and the power of the engine are used to characterize the load of the engine. Therefore, the vehicle controller indirectly determines the load condition of the engine by the second method or the third method.

[0072] Step 302: The vehicle controller determines the opening value of the valve device based on the load condition.

[0073] It should be understood that the "opening value of the valve device" in the above step 302 can be simply understood as the opening angle of the valve device, with the unit being degrees. The range of the opening value is (0, 90].

[0074] It should also be understood that when the engine is in different load conditions, the airflow velocity of the exhaust gas discharged by the engine when it flows into the mixer (the air inlet of the mixer) is different, the degree of airflow disturbance in the mixer is different, and the degree of mixing of the exhaust gas reductant and the exhaust gas is different. Relatively speaking, the smaller the load corresponding to the load condition, the more it is necessary to increase the airflow velocity when the exhaust gas flows into the mixer, and the more it is necessary to make the airflow disturbance in the mixer sufficient. Since the air flows into the engine at a fixed mass flow rate, the smaller the air intake area of ​​the air inlet of the mixer, the greater the airflow velocity when the exhaust gas flows into the mixer, and the more sufficient the airflow disturbance in the mixer. Therefore, the smaller the load corresponding to the load condition, the more it is necessary to reduce the air intake area of ​​the air inlet of the mixer. The present application controls the air intake area of ​​the air inlet of the mixer by a valve device arranged upstream of the mixer, and specifically controls the air intake area of ​​the air inlet by the opening value of the valve device.

[0075] It should also be understood that when the load corresponding to the load condition is relatively large, the present application can also increase the air intake area of ​​the air intake port of the mixer by adjusting the opening value of the valve device.

[0076] In one possible implementation, step 302 includes: when the load condition is the first condition, the vehicle controller determines the first opening value as the opening value; when the load condition is the second condition, the vehicle controller determines the second opening value as the opening value; when the load condition is the third condition, the vehicle controller determines the third opening value as the opening value; wherein, the load corresponding to the first condition is smaller than the load corresponding to the second condition, the load corresponding to the second condition is smaller than the load corresponding to the third condition, the first opening value is smaller than the second opening value, and the second opening value is smaller than the third opening value.

[0077] In some embodiments, the first operating condition is a small load condition, the second operating condition is a medium load condition, and the third operating condition is a large load condition or a full load condition.

[0078] In some embodiments, when the engine is in a high load condition or a full load condition, the opening value of the valve device is 90°.

[0079] In the above technical solution, when the load condition is specifically different load conditions, the corresponding different opening values ​​of the valve device are described. The first opening value under the small load condition is smaller than the second opening value under the medium load condition, and the second opening value under the medium load condition is smaller than the third opening value under the large load condition or the full load condition. This is due to the following reasons: the smaller the load corresponding to the load condition, the smaller the airflow velocity when the exhaust gas discharged by the engine flows into the mixer (the air inlet of the mixer). This will cause the airflow disturbance in the mixer in the engine exhaust gas treatment system to be less sufficient, resulting in the mixing of the exhaust gas reductant and the exhaust gas to be more uneven. In this regard, the smaller the load corresponding to the load condition, the more it is necessary to increase the airflow disturbance in the mixer, the more it is necessary to reduce the air intake area of ​​the air inlet of the mixer, and the more it is necessary to adjust the opening value of the valve device to a smaller value. Among them, when the mass flow rate of air is fixed, the smaller the air intake area of ​​the air inlet of the mixer, the greater the airflow velocity when the exhaust gas flows into the mixer (the air inlet of the mixer), and the more sufficient the airflow disturbance in the mixer.

[0080] In one possible implementation, before step 302, the method 300 further includes: the vehicle controller obtains the driving speed of the vehicle including the engine exhaust treatment system; and step 302 includes: the vehicle controller determines the opening value of the valve device based on the driving speed and the load condition.

[0081] In the above technical solution, under different vehicle speeds and different load conditions, the intake pressure and intake density of the engine are different, and the air flow disturbance in the mixer is different. Under different air flow disturbances, the mixing degree of the exhaust gas reducing agent and the exhaust gas is different. In order to fully mix the exhaust gas reducing agent and the exhaust gas, the degree of air flow disturbance in the mixer can be appropriately controlled by adjusting the opening value of the valve device. Specifically, the opening value of the valve device is adjusted based on the driving speed and the load condition.

[0082] In some embodiments, the vehicle controller determines the opening value of the valve device based on the driving speed and the load condition, including: the vehicle controller determines a fourth opening value of the valve device based on the load condition; when the driving speed is less than a preset speed, the vehicle controller corrects the fourth opening value to a fifth opening value, which is less than the fourth opening value; when the driving speed is greater than the preset speed, the vehicle controller corrects the fourth opening value to a sixth opening value, which is greater than the fourth opening value; when the driving speed is equal to the preset speed, the vehicle controller controls the fourth opening value to remain unchanged.

[0083] In the above technical solution, the lower the vehicle's speed, the more it will affect the airflow velocity when the exhaust gas discharged by the engine flows into the mixer (the air inlet of the mixer). Specifically, the lower the vehicle's speed, the less the airflow disturbance in the mixer will be, which will cause the degree of mixing of the exhaust gas reductant and the exhaust gas to be uneven. Therefore, when the vehicle's speed is relatively low, the opening value can be further reduced based on the opening value determined based on the vehicle's speed. Correspondingly, when the vehicle's speed is relatively high, the opening value can be further increased based on the opening value determined based on the vehicle's speed. When the vehicle's speed is medium, the opening value determined based on the vehicle's speed may not be adjusted.

[0084] In some embodiments, when the air flow meter obtains that the mass flow rate of air flowing into the engine is in a first mass flow rate range, the vehicle controller determines that the engine is in a low load condition. At this time, the opening value of the valve device is determined to be 20°. A smaller opening value is defined by a smaller air mass flow rate to achieve a larger air flow rate when the exhaust gas flows into the mixer.

[0085] When the air flow meter obtains that the mass flow of air flowing into the engine is in the second mass flow range, the vehicle controller determines that the engine is in a medium load condition. At this time, the opening value of the valve device is determined to be 50°. The moderate opening value is defined by the moderate mass flow of air to achieve a moderate air flow rate when the exhaust gas flows into the mixer.

[0086] When the air flow meter obtains that the mass flow rate of air flowing into the engine is in the third mass flow rate range, the vehicle controller determines that the engine is in a low load condition. At this time, the opening value of the valve device is determined to be 90°. A larger opening value is defined by a larger air mass flow rate to achieve a larger air flow rate when the exhaust gas flows into the mixer, thereby achieving uniform mixing of the urea aqueous solution and the exhaust gas.

[0087] Step 303: the vehicle controller controls the valve device to open to the opening value to control the exhaust gas discharged by the engine to flow into the mixer through the air inlet.

[0088] In some embodiments, the structure of the "valve device" in step 303 is a planar structure or a curved structure with swirl.

[0089] In some embodiments, the "valve device" in step 303 is a solenoid valve, and step 303 includes: the vehicle controller controls the current of the solenoid valve, and the magnetic field generated by the current of the solenoid valve controls the movement of the valve core in the solenoid valve to control the solenoid valve to open to the opening value.

[0090] In the above technical solution, the opening value of the solenoid valve is used to indicate the maximum degree to which the valve core can be opened during operation. The larger the opening value of the solenoid valve, the larger the volume flow rate of the fluid medium passing through the solenoid valve, and the smaller the mass flow rate of the fluid medium. The opening value of the solenoid valve can be achieved by controlling the current of the solenoid valve.

[0091] In one possible implementation, the valve device includes a rotating valve stem and a valve, the rotating valve stem is connected to the valve, and the valve includes any one of a ball valve, a gate valve, a stop valve, a butterfly valve and a regulating valve. Step 303 includes: the vehicle controller controls the rotation of the rotating valve stem to control the valve to open to the opening value.

[0092] In the above technical solution, the valve device is described as including a rotating valve stem and a valve, and the rotating valve stem is connected to the valve. When the valve includes any one of a ball valve, a gate valve, a stop valve, a butterfly valve and a regulating valve, the rotation of the rotating valve stem can be controlled to drive the valve to rotate, so as to control the process of opening the valve to the opening value.

[0093] Figure 4 It is a schematic diagram of the structure of a valve device provided in an embodiment of the present application.

[0094] For example, taking the valve as a stop valve as an example, the process of opening the valve to the target opening value is described. Figure 4 As shown in (a) in the figure, the valve can be moved upward or downward by rotating the rotary valve stem to adjust the air intake area of ​​the air inlet of the mixer.

[0095] In another exemplary embodiment, taking the valve as a regulating valve as an example, the process of opening the valve to the target opening value is described. Figure 4 As shown in (b) in the figure, the valve can be moved upward or downward by rotating the rotary valve stem to adjust the air intake area of ​​the air inlet of the mixer.

[0096] Figure 5 It is a structural schematic diagram of a control device for an engine exhaust treatment system provided in an embodiment of the present application.

[0097] Exemplarily, the engine exhaust treatment system includes a mixer and a valve device disposed upstream of the mixer, the engine exhaust treatment system is connected to the engine through the valve device, the exhaust gas discharged by the engine flows into the mixer through the valve device, the valve device is used to control the intake area of ​​the air inlet of the mixer, and the mixer is used to mix the exhaust gas reductant and the exhaust gas discharged by the engine, such as Figure 5 As shown, the device 500 includes:

[0098] The determination module 501 is used to:

[0099] Determine the load condition of the engine;

[0100] Based on the load condition, determining the opening value of the valve device;

[0101] The control module 502 is used to control the valve device to open to the opening value, so as to control the exhaust gas discharged by the engine to flow into the mixer through the air inlet.

[0102] Optionally, the determination module 501 is specifically used to: obtain the mass flow rate of air flowing into the engine through the air flow meter, the air flow meter is connected to the engine, and the mass flow rate is used to characterize the load of the engine; determine the mass flow rate range of the mass flow rate; based on the mass flow rate range, determine the load condition of the engine.

[0103] Optionally, the determination module 501 is further specifically used to: obtain the speed of the engine through a speed sensor connected to the engine, and obtain the opening angle of the throttle through a throttle position sensor arranged on the throttle, the throttle is connected to the engine and is used to control the mass flow rate of air flowing into the engine; determine the load of the engine based on the speed and the opening angle of the throttle; determine the load condition of the engine based on the load range in which the load is located.

[0104] Optionally, the determination module 501 is further specifically used to: when the load condition is the first condition, determine the first opening value as the opening value; when the load condition is the second condition, determine the second opening value as the opening value; when the load condition is the third condition, determine the third opening value as the opening value; wherein, the load corresponding to the first condition is smaller than the load corresponding to the second condition, the load corresponding to the second condition is smaller than the load corresponding to the third condition, the first opening value is smaller than the second opening value, and the second opening value is smaller than the third opening value.

[0105] Optionally, the valve device includes a rotating valve stem and a valve, the rotating valve stem is connected to the valve, the valve includes any one of a ball valve, a gate valve, a stop valve, a butterfly valve and a regulating valve, and the control module is specifically used to control the rotation of the rotating valve stem to control the valve to open to the opening value.

[0106] Optionally, the device 500 further includes: an acquisition module for acquiring a driving speed of a vehicle including the engine exhaust treatment system; and the determination module is further specifically used to determine an opening value of the valve device based on the driving speed and the load condition.

[0107] Figure 6 It is a structural schematic diagram of an engine exhaust treatment system provided in an embodiment of the present application.

[0108] For example, Figure 6 As shown, the engine exhaust treatment system 600 includes a target controller 601 , a mixer 602 and a valve device 603 , and the engine exhaust treatment system 600 is connected to an engine 604 via the valve device 603 .

[0109] The valve device 603 is connected to the mixer 602 and is disposed upstream of the mixer 602 , and is used to control the intake area of ​​the intake port 605 of the mixer 602 . The exhaust gas discharged by the engine 604 flows into the mixer 602 through the valve device 603 .

[0110] The target controller 601 is connected to the valve device 603 and is used to control the opening value of the valve device 603 based on the load condition of the engine 604 .

[0111] The mixer 602 is used to mix the exhaust gas reductant and the exhaust gas discharged by the engine 604 .

[0112] It should be understood that the mixer 602 is Figure 1 The mixer 1064 shown in (c) in FIG. 1 has a valve device 603. Figure 2 The valve device 1066 in the engine 604 is Figure 1 The engine 104 shown in (a) .

[0113] Figure 7 It is a schematic diagram of the structure of another engine exhaust treatment system provided in an embodiment of the present application.

[0114] For example, Figure 7 As shown, the target controller 601 is connected to an air flow meter 706 , and the air flow meter 706 is connected to the engine 604 .

[0115] The target controller 601 is further used to: obtain the mass flow rate of the air flowing into the engine 604 through the air flow meter 706; and determine the load condition of the engine 604 based on the mass flow rate.

[0116] It should be understood that Figure 7 The air flow meter 706 is Figure 1 The air flow meter 1012 shown in (b) in FIG.

[0117] Figure 8 It is a structural schematic diagram of a vehicle provided in an embodiment of the present application.

[0118] For example, Figure 8 As shown, the vehicle 800 includes: a memory 801, a processor 802, and a computer program 803 stored in the memory 801 and running on the processor 802, wherein when the processor 802 executes the computer program 803, the vehicle controller in the vehicle can execute any one of the control methods for the engine exhaust treatment system introduced above.

[0119] In this embodiment, the functional modules of the vehicle can be divided according to the above method example. For example, each functional module can be corresponded, or two or more functions can be integrated into one processing module. The above integrated module can be implemented in the form of hardware. It should be noted that the division of modules in this embodiment is schematic and is only a logical function division. There may be other division methods in actual implementation.

[0120] In the case of dividing each functional module according to each function, the vehicle may include: a determination module, a control module, an acquisition module, etc. It should be noted that all relevant contents of each step involved in the above method embodiment can be referred to the functional description of the corresponding functional module, which will not be repeated here.

[0121] The vehicle provided in this embodiment is used to execute the above-mentioned control method of an engine exhaust treatment system, and thus can achieve the same effect as the above-mentioned implementation method.

[0122] In the case of an integrated unit, the vehicle may include a processing module and a storage module. The processing module may be used to control and manage the actions of the vehicle. The storage module may be used for the vehicle to execute mutual program codes and data.

[0123] The processing module may be a processor or a controller, which may implement or execute various exemplary logic blocks, modules and circuits disclosed in the present application. The processor may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of digital signal processing (DSP) and a microprocessor, etc. The storage module may be a memory.

[0124] This embodiment provides a computer-readable storage medium, in which instructions are stored. When the instructions are executed on a computer or a processor, the computer or the processor executes any one of the control methods for the engine exhaust treatment system described above.

[0125] This embodiment also provides a computer program product including instructions. When the computer program product is run on a computer or a processor, the computer or the processor executes the above-mentioned related steps to implement any of the control methods for the engine exhaust treatment system introduced above.

[0126] Among them, the vehicle, computer-readable storage medium, computer program product or chip containing instructions provided in this embodiment are all used to execute the corresponding methods provided above. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects in the corresponding methods provided above, and will not be repeated here.

[0127] Through the description of the above implementation methods, technical personnel in the relevant field can understand that for the convenience and simplicity of description, only the division of the above-mentioned functional modules is used as an example. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0128] In the embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of modules or units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0129] The above contents are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A control method for an engine exhaust treatment system, characterized in that: The engine exhaust treatment system comprises a mixer and a valve device arranged upstream of the mixer, the engine exhaust treatment system is connected to the engine through the valve device, the exhaust gas discharged by the engine flows into the mixer through the valve device, the valve device is used to control the intake area of ​​the air inlet of the mixer, the mixer is used to mix the exhaust gas reductant and the exhaust gas discharged by the engine, and the method comprises: determining a load condition of the engine; Based on the load condition, determining the opening value of the valve device; The valve device is controlled to open to the opening value to control the exhaust gas discharged by the engine to flow into the mixer through the air intake port.

2. The method according to claim 1, characterized in that Determining the load condition of the engine includes: obtaining a mass flow rate of air flowing into the engine through an air flow meter, wherein the mass flow rate is used to characterize a load of the engine; determining a mass flow range within which the mass flow falls; Based on the mass flow range, a load condition of the engine is determined.

3. The method according to claim 1, characterized in that Determining the load condition of the engine includes: The speed of the engine is obtained by a speed sensor connected to the engine, and the opening angle of the throttle is obtained by a throttle position sensor provided on the throttle, wherein the throttle is connected to the engine and is used to control the mass flow of air flowing into the engine; determining a load of the engine based on the rotational speed and the opening angle; Based on the load range in which the load is located, a load condition of the engine is determined.

4. The method according to claim 1, characterized in that: The step of determining the opening value of the valve device based on the load condition comprises: When the load condition is the first condition, determining the first opening value as the opening value; When the load condition is the second condition, determining the second opening value as the opening value; When the load condition is the third condition, determining the third opening value as the opening value; Among them, the load corresponding to the first working condition is smaller than the load corresponding to the second working condition, the load corresponding to the second working condition is smaller than the load corresponding to the third working condition, the first opening value is smaller than the second opening value, and the second opening value is smaller than the third opening value.

5. The method according to claim 1, characterized in that The valve device comprises a rotary valve stem and a valve, wherein the rotary valve stem is connected to the valve, and the valve comprises any one of a ball valve, a gate valve, a stop valve, a butterfly valve and a regulating valve, and the controlling the valve device to open to the opening value comprises: The rotary valve stem is controlled to rotate so as to control the valve to open to the opening value.

6. The method according to claim 1, characterized in that The method further comprises: obtaining a driving speed of a vehicle including the engine exhaust treatment system; And, determining the opening value of the valve device based on the load condition includes: Based on the driving speed and the load condition, an opening value of the valve device is determined.

7. An engine exhaust treatment system, characterized in that: The engine exhaust treatment system comprises a target controller, a mixer and a valve device, and the engine exhaust treatment system is connected to the engine through the valve device; The valve device is connected to the mixer and is arranged upstream of the mixer, and is used to control the intake area of ​​the intake port of the mixer, and the exhaust gas discharged by the engine flows into the mixer through the valve device; The target controller is connected to the valve device and is used to control the opening value of the valve device based on the load condition of the engine; The mixer is used to mix the exhaust gas reducing agent with the exhaust gas discharged from the engine.

8. The engine exhaust treatment system according to claim 7, characterized in that: The target controller is connected to an air flow meter; The target controller is further configured to: obtaining the mass flow rate of air flowing into the engine through the air flow meter; Based on the mass flow rate, a load condition of the engine is determined.

9. A vehicle, characterized in that: It includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the target controller in the vehicle executes the control method of the engine exhaust treatment system as described in any one of claims 1 to 6.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores instructions, and when the instructions are executed on a computer or a processor, the computer or the processor executes the control method of the engine exhaust treatment system according to any one of claims 1 to 6.

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