Double-spraying SCR aftertreatment control system and method and vehicle

Abstract

The invention provides a double-spraying SCR aftertreatment control system and method and a vehicle. According to the system, after tail gas exhausted by an engine is primarily treated through selective catalytic reducers, a diesel oxidation catalyst and a particulate trap in a first treatment passage of the double-injection SCR aftertreatment system, the opening degree of an airflow direction valve is controlled through a control unit according to the concentration of particulate matter in the treated tail gas, and then the tail gas is subjected to secondary treatment; and distributing the flow rate of the treated tail gas flowing to the second treatment passage or the third treatment passage. The low-back-pressure second treatment passage is selected under the condition that the particulate matter quantity emission does not exceed the standard, and the low-emission third treatment passage is selected when the particulate matter quantity exceeds the standard risk, so that the oil consumption loss is reduced as much as possible on the basis of ensuring that the particulate matter emission reaches the standard, and the economical efficiency of the engine is improved.

Description

Technical Field

[0001] The present application relates to the technical field of engine after-treatment, and in particular to a dual-injection SCR after-treatment control system, method and vehicle. Background Art

[0002] As a vehicle exhaust treatment solution, the dual-injection SCR (Selective Catalytic Reduction) after-treatment solution can effectively meet the requirements of exhaust emission regulations, and is therefore widely used in various current vehicles.

[0003] The existing dual-injection SCR after-treatment scheme has put forward higher requirements for precise control of the urea injection amount, but it also increases the particulate matter in the exhaust gas when the dual-injection SCR after-treatment scheme injects too much or too little urea, thereby increasing the risk of exceeding the emission standard.

[0004] Therefore, existing improvement schemes usually add a diesel particulate filter at the end of the dual-injection SCR after-treatment system. The added diesel particulate filter leads to an increase in exhaust back pressure, which causes an increase in fuel consumption and reduces the economy of the engine. Summary of the invention

[0005] The embodiments of the present application provide a dual-injection SCR after-treatment control system and a vehicle to solve the defect that the existing improvement scheme adds a diesel particulate filter at the end of the dual-injection SCR after-treatment system, resulting in an increase in exhaust back pressure, causing increased fuel consumption and reduced engine economy.

[0006] In the first aspect, an embodiment of the present application provides a dual-injection SCR after-treatment control system, including: a dual-injection SCR after-treatment system, an airflow direction valve and a control unit, the dual-injection SCR after-treatment system including: a first processing path, a second processing path and a third processing path, the first processing path including: a first DPF module, a first SCR module and a particulate matter detection module in sequence, the second processing path including a pipeline, and the third processing path including a second DPF module; the output end of the first processing path, the input end of the second processing path, and the input end of the third processing path are connected through an airflow direction valve, the airflow direction valve is communicatively connected to the control unit, and the control unit is used to control the opening of the airflow direction valve according to the particle size concentration sent by the particulate matter detection module to adjust the gas ratio passing through the second processing path and the third processing path.

[0007] In a possible implementation, a silencer module is provided on the second processing passage to eliminate exhaust emission noise.

[0008] In a possible implementation, a cooling module is provided on the second processing passage for cooling the exhaust gas.

[0009] In a possible implementation, the second DPF module is coated with an SCR catalyst and / or an ASC catalyst.

[0010] In a possible embodiment, the first processing path also includes: a DOC module located before the first DPF module; and / or, a second SCR module located before the DOC module; and / or, an ASC module integrated with the first SCR module; and / or, an electric heating module located before the DOC module.

[0011] In a possible implementation, the first DPF module is coated with an oxidative catalyst.

[0012] In a third aspect, an embodiment of the present application provides a dual-injection SCR after-treatment control method, which is applied to the above-mentioned dual-injection SCR after-treatment control system, including: a control unit receives the particulate matter concentration sent by the particulate matter detection module; the control unit determines the target opening of the airflow direction valve according to the size relationship between the particulate matter concentration and a preset concentration threshold; the control unit controls the airflow direction valve according to the target opening of the airflow direction valve.

[0013] In a possible implementation, the control unit determines the target opening of the airflow direction valve based on the magnitude relationship between the particle concentration and a preset concentration threshold, including: the control unit determines the concentration difference between the preset concentration threshold and the particle concentration; the control unit determines the target opening of the airflow direction valve based on the absolute value and sign of the concentration difference.

[0014] In a possible implementation, the control unit determines the target opening of the airflow direction valve according to the absolute value and sign of the concentration difference, including: if the absolute value of the concentration difference is greater than or equal to the first concentration threshold value, and the sign is positive, the control unit controls the airflow direction valve to be the first opening to fully connect the first processing passage and the second processing passage, and shut off the first processing passage and the third processing passage; if the absolute value of the concentration difference is greater than or equal to the second concentration threshold value, and the sign is negative, the control unit controls the airflow direction valve to be the second opening to fully connect the first processing passage and the third processing passage, and shut off the first processing passage and the second processing passage; if the absolute value of the concentration difference is between the first concentration threshold value and the second concentration threshold value, the control unit controls the airflow direction valve to be the third opening to partially connect the first processing passage and the third processing passage, and partially connect the first processing passage and the second processing passage, when the sign is positive, the gas passing through the third processing passage is less than the gas passing through the second processing passage, and when the sign is negative, the gas passing through the third processing passage is more than the gas passing through the second processing passage.

[0015] In a third aspect, an embodiment of the present application provides a vehicle, comprising the above-mentioned dual-injection SCR after-treatment control system.

[0016] The present application provides a dual-injection SCR post-treatment control system, method and vehicle, which realizes preliminary treatment of the exhaust gas discharged by the engine through each selective catalytic reducer, diesel oxidation catalyst and particulate trap in the first treatment channel of the dual-injection SCR post-treatment system, and controls the opening of the airflow direction valve through the control unit according to the concentration of particulate matter in the treated exhaust gas, and distributes the treated exhaust gas flow to the second treatment channel or the third treatment channel. When the number of particulate matter emissions does not exceed the standard, the second treatment channel with low back pressure is selected, and when there is a risk of exceeding the standard, the third treatment channel with low emissions is selected, thereby reducing fuel consumption losses as much as possible on the basis of ensuring that the particulate matter emissions meet the standard, and improving the economy of the engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0018] Figure 1 A schematic diagram of the existing improved solution system provided for this application.

[0019] Figure 2 Schematic diagram of the dual-injection SCR post-treatment control system architecture provided for this application Figure 1 .

[0020] Figure 3 Schematic diagram of the dual-injection SCR post-treatment control system architecture provided for this application Figure 2 .

[0021] Figure 4 Schematic diagram of the process of the dual-injection SCR post-treatment control method provided in this application Figure 1 .

[0022] Figure 5 Schematic diagram of the process of the dual-injection SCR post-treatment control method provided in this application Figure 2 .

[0023] Figure markings: 1-first processing path; 101-first DPF module; 102-first SCR module; 103-particulate matter detection module; 104-DOC module; 105-second SCR module; 106-ASC module; 2-second processing path; 201-muffler module; 202-cooling module; 3-third processing path; 301-second DPF module; 4-air flow direction valve; 5-control unit.

[0024] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0025] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0026] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in one or more embodiments of this specification are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant laws, regulations and standards, and corresponding operation entrances shall be provided for users to choose to authorize or refuse.

[0027] It should be noted that in the embodiments of the present application, certain software, components, models and other existing solutions in the industry may be mentioned, and they should be regarded as exemplary. Their purpose is only to illustrate the feasibility of implementing the technical solution of the present application, but it does not mean that the applicant has or will necessarily use the solution.

[0028] As vehicle exhaust pollutant emission regulations increase, it is necessary to reduce nitrogen oxides in exhaust gas. The emission limit is lowered and the particle size of the discharged particulate matter is reduced. However, the existing after-treatment system, namely DOC (Diesel Oxidation Catalyst) + DPF (Diesel Particulate Filter) + SCR (Selective Catalytic Reduction), can no longer meet the emission requirements.

[0029] Therefore, the existing solutions generally use the dual-injection SCR (Selective Catalytic Reduction) post-treatment solution as the main vehicle exhaust treatment solution. The dual-injection SCR post-treatment solution includes the front-stage SCR + DOC (Diesel Oxidation Catalyst) + DPF (Diesel Particulate Filter) + rear-stage SCR.

[0030] However, the dual-injection SCR post-treatment solution requires a high level of precise control and distribution strategy for the two-stage urea injection. If the total amount of urea injected in the dual-injection SCR post-treatment system is too small, it is easy to increase the risk of excessive nitrogen oxide content in the treated exhaust gas; if the total amount of urea injected in the system is too high, ammonia will leak in the treated exhaust gas, and the amount of nitrous oxide and particulate matter will increase. The risk of exceeding the standard increases; if the urea corresponding to the front-stage SCR is injected too much, the risk of nitrous oxide exceeding the standard in the treated exhaust gas is high, and the passive regeneration performance of the diesel particulate filter is weakened; if the urea corresponding to the front-stage SCR is injected too little and the rear-stage urea is injected too much, there is a risk of excessive particulate matter and ammonia leakage in the treated exhaust gas.

[0031] In order to reduce the precise control requirements of the dual-injection SCR after-treatment scheme on the two-stage urea injection and increase the robustness of the dual-injection SCR after-treatment system, Figure 1 This is a schematic diagram of the existing improvement solution system. Figure 1 As shown in the figure, the existing improvement scheme achieves secondary interception of particulate matter emitted by the engine and newly generated small-size particulate matter by post-urea injection by adding a DPF diesel particulate filter at the end of the dual-injection SCR post-treatment system. However, the newly added diesel particulate filter increases the exhaust back pressure of the post-treatment system, which reduces the emission of pollutants but also increases fuel consumption and reduces the economy of the engine.

[0032] In view of this, the present application provides a dual-injection SCR post-treatment control system, including a dual-injection SCR post-treatment system, an airflow direction valve and a control unit. Among them, the dual-injection SCR post-treatment system includes a first processing channel, a second processing channel and a third processing channel. Through the selective catalytic reducer, diesel oxidation catalyst and particulate trap in the first processing channel, the exhaust gas discharged by the engine is preliminarily treated, and the opening of the airflow direction valve is controlled by the control unit according to the concentration of particulate matter in the treated exhaust gas, and the treated exhaust gas flow to the second processing channel or the third processing channel is distributed. When the number of particulate matter emissions does not exceed the standard, the second processing channel with low back pressure is selected, and when the number of particulate matter is at risk of exceeding the standard, the third processing channel with low emissions is selected, thereby reducing fuel consumption losses as much as possible on the basis of ensuring that the particulate matter emissions meet the standard, and improving the economy of the engine.

[0033] The technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems are described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0034] Figure 2 Schematic diagram of the dual-injection SCR post-treatment control system architecture provided for this application Figure 1 ,like Figure 2 As shown, the dual-injection SCR after-treatment control system includes: a dual-injection SCR after-treatment system, an airflow direction valve 4 and a control unit 5.

[0035] The dual-injection SCR post-treatment system includes: a first processing passage 1, a second processing passage 2 and a third processing passage 3. The output end of the first processing passage 1, the input end of the second processing passage 2 and the input end of the third processing passage 3 are connected through an airflow direction valve 4, and the airflow direction valve 4 is communicatively connected to a control unit 5. The control unit 5 is used to control the opening of the airflow direction valve 4 according to the particle size concentration sent by the particle detection module 103, so as to adjust the gas ratio passing through the second processing passage 2 and the third processing passage 3.

[0036] Further, the first processing channel 1 includes: a first DPF module 101 , a first SCR module 102 and a particulate matter detection module 103 in sequence, the second processing channel 2 includes a pipeline 201 , and the third processing channel 3 includes a second DPF module 301 .

[0037] Furthermore, the first processing path 1 also includes a DOC module 104 located before the first DPF module 101, a second SCR module 105 located before the DOC module 104, an ASC module 106 integrated with the first SCR module, and an electric heating module located before the DOC module 104. The exhaust gas is heated by the electric heating module to increase the temperature of downstream equipment and promote the startup and regeneration of the first DPF module 101.

[0038] Specifically, after the exhaust gas discharged by the vehicle engine enters the dual-injection SCR after-treatment system, the exhaust gas passes through the second SCR module 105 in the first processing passage 1, wherein the exhaust gas is sprayed with urea solution through the urea injection device corresponding to the second SCR module 105, so that the urea is decomposed at high temperature to generate ammonia, and based on the mixture of ammonia and exhaust gas, the nitrogen oxides in the exhaust gas are preliminarily reduced to nitrogen and water vapor under the action of the SCR catalyst in the second SCR module 105.

[0039] Furthermore, after the exhaust gas is preliminarily treated by the second SCR module 105 in the first treatment passage 1 , the carbon monoxide, hydrocarbons, nitrogen monoxide and oxygen in the exhaust gas are further converted into water and carbon dioxide by the DOC module 104 under the catalytic action of precious metals.

[0040] After the exhaust gas passes through the DOC module 104, the particulate matter in the exhaust gas is captured by the first DPF module 101. After the particulate matter in the exhaust gas is initially captured by the first DPF module 101, the urea solution is sprayed on the exhaust gas again through the urea injection device corresponding to the first SCR module 102, and based on the ammonia decomposed by urea, the nitrogen oxides in the exhaust gas are reduced to nitrogen and water vapor again under the action of the SCR catalyst in the first SCR module 102, and the residual ammonia in the exhaust gas is captured by the ASC module 106.

[0041] After the exhaust gas is processed by the second SCR module 105, the DOC module 104, the first DPF module 101, the first SCR module 102 and the ASC module 106 in the first processing path 1 in sequence, the concentration of particulate matter in the exhaust gas at this time is obtained by the particulate matter detection module 103, and the obtained particulate matter concentration information is sent to the control unit 5, so that the control unit 5 controls the opening of the airflow direction valve 4 according to the concentration of particulate matter in the exhaust gas after treatment.

[0042] Among them, when the acquired particulate matter concentration is less than the preset concentration threshold, the air flow direction valve 4 is controlled to be closed, so that the treated exhaust gas flows to the second processing passage 2 with low back pressure, and directly flows to the outside through the second processing passage 2; when the particulate matter concentration is greater than or equal to the preset concentration threshold, the air flow direction valve 4 is controlled to be opened, so that the treated exhaust gas flows to the third processing passage 3 including the second DPF module 301, and the particulate matter in the exhaust gas is captured again through the second DPF module 301, thereby ensuring that the particulate matter emissions meet the standards.

[0043] The embodiment of the present application provides a dual-injection SCR post-treatment control system, including a dual-injection SCR post-treatment system, an airflow direction valve and a control unit. The dual-injection SCR post-treatment system includes a first processing channel, a second processing channel and a third processing channel. Through the selective catalytic reducer, diesel oxidation catalyst and particulate trap in the first processing channel, the exhaust gas discharged by the engine is preliminarily treated, and then the opening of the airflow direction valve is controlled by the control unit according to the concentration of particulate matter in the treated exhaust gas, and the treated exhaust gas flow to the second processing channel or the third processing channel is distributed. When the number of particulate matter emissions does not exceed the standard, the second processing channel with low back pressure is selected, and when there is a risk of exceeding the standard, the third processing channel with low emissions is selected, thereby reducing fuel consumption losses as much as possible on the basis of ensuring that the particulate matter emissions meet the standard, thereby improving the economy of the engine.

[0044] Figure 3 Schematic diagram of the dual-injection SCR post-treatment control system architecture provided for this application Figure 2 ,like Figure 3 As shown, in this embodiment Figure 2 On the basis of the embodiment, the dual-injection SCR after-treatment control system is described in detail, in which the second processing passage 2 in the dual-injection SCR after-treatment control system is provided with a silencing module 201 and a cooling module 202, wherein the silencing module 201 is used to eliminate the exhaust emission noise, and the cooling module 202 is used to cool the exhaust gas.

[0045] Furthermore, the second DPF module 301 is coated with an SCR catalyst and / or an ASC catalyst.

[0046] Specifically, after the exhaust gas is processed by the second SCR module 105, the DOC module 104, the first DPF module 101, the first SCR module 102 and the ASC module 106 in the first processing passage 1, and after passing through the particulate matter detection module 103 and detecting that the particulate matter concentration in the exhaust gas at this time is less than the preset concentration threshold, the control unit 5 controls the airflow direction valve 4 to close, so that the treated exhaust gas flows to the second processing passage 2 with low back pressure. After the exhaust gas enters the second processing passage 2, the noise accompanying the exhaust gas is absorbed by the silencing module 201, and then the heat of the exhaust gas to be discharged to the outside is absorbed by the cooling module 202, so as to further reduce the pollution and negative impact of the exhaust gas on the surrounding environment.

[0047] Furthermore, after the exhaust gas is processed by each module in the first processing passage 1, the particulate matter detection module 103 detects that the concentration of particulate matter in the exhaust gas at this time is greater than or equal to a preset concentration threshold, and controls the airflow direction valve 4 to open, so that the treated exhaust gas flows to the third processing passage 3 including the second DPF module 301, wherein the nitrogen oxides in the exhaust gas are processed and reduced again by the SCR catalyst and / or the ASC catalyst in the second DPF module 301, and the ammonia substances in the exhaust gas are captured, so as to further process the nitrogen oxides, ammonia substances and particulate matter remaining in the exhaust gas.

[0048] The embodiment of the present application provides a dual-injection SCR post-treatment control system, including a dual-injection SCR post-treatment system, an airflow direction valve and a control unit. The dual-injection SCR post-treatment system includes a first processing channel, a second processing channel and a third processing channel. Through the selective catalytic reducer, diesel oxidation catalyst and particulate trap in the first processing channel, the exhaust gas discharged by the engine is preliminarily treated, and then the opening of the airflow direction valve is controlled by the control unit according to the concentration of particulate matter in the treated exhaust gas, and the treated exhaust gas flow to the second processing channel or the third processing channel is distributed. When the number of particulate matter emissions does not exceed the standard, the second processing channel with low back pressure is selected, and when there is a risk of exceeding the standard, the third processing channel with low emissions is selected, thereby reducing fuel consumption losses as much as possible on the basis of ensuring that the particulate matter emissions meet the standard, thereby improving the economy of the engine.

[0049] Figure 4 Schematic diagram of the process of the dual-injection SCR post-treatment control method provided in this application Figure 1 ,like Figure 4 As shown, in this embodiment Figure 3 Based on the embodiment, a dual-injection SCR post-treatment control method is described in detail. The method is applied to the control unit 5. The method includes: S101, the control unit receives the particle concentration sent by the particle detection module.

[0050] Specifically, after the exhaust gas is processed by the second SCR module 105, the DOC module 104, the first DPF module 101, the first SCR module 102 and the ASC module 106 in the first processing path 1, the particulate matter status information in the exhaust gas at this time is detected by the particulate matter detection module 103, and the particulate matter status information is sent to the control unit 5, wherein the particulate matter status information is used to indicate the current concentration of particulate matter in the exhaust gas, so that the control unit 5 controls the opening of the airflow direction valve 4 according to the acquired particulate matter concentration.

[0051] S102: The control unit determines a target opening of the airflow direction valve according to a magnitude relationship between the particle concentration and a preset concentration threshold.

[0052] Specifically, after the control unit 5 obtains the current particle matter concentration, it detects whether the particle matter concentration is in the preset concentration threshold range. If it is detected that the particle matter concentration is not in the preset concentration threshold range, and if the particle matter concentration is greater than the maximum value of the preset concentration threshold range, the airflow direction valve 4 is opened, that is, the opening of the airflow direction valve 4 is one hundred; if the particle matter concentration is less than the minimum value of the preset concentration threshold range, the airflow direction valve 4 needs to be kept closed, that is, the opening of the airflow direction valve 4 is determined to be zero.

[0053] S103: The control unit controls the airflow directional valve according to the target opening of the airflow directional valve.

[0054] Specifically, after determining the target opening corresponding to the airflow direction valve 4 according to the particulate matter concentration, the airflow direction valve 4 is controlled by the control unit 5 to achieve the corresponding target opening, so that the treated exhaust gas enters the second processing passage 2 with low back pressure based on the target opening of the airflow direction valve 4, or the third processing passage 3 that can further process the residual nitrogen oxides, ammonia substances and particulate matter in the exhaust gas.

[0055] The embodiment of the present application provides a dual-injection SCR post-treatment control method, which realizes preliminary treatment of the exhaust gas discharged by the engine through each selective catalytic reducer, diesel oxidation catalyst and particulate trap in the first treatment channel of the dual-injection SCR post-treatment system, and then controls the opening of the airflow direction valve through the control unit according to the concentration of particulate matter in the treated exhaust gas, and distributes the treated exhaust gas flow to the second treatment channel or the third treatment channel. When the number of particulate matter emissions does not exceed the standard, the second treatment channel with low back pressure is selected, and when there is a risk of exceeding the standard, the third treatment channel with low emissions is selected, thereby reducing fuel consumption losses as much as possible on the basis of ensuring that the particulate matter emissions meet the standard, thereby improving the economy of the engine.

[0056] Figure 5 Schematic diagram of the process of the dual-injection SCR post-treatment control method provided in this application Figure 2 ,like Figure 5 As shown, in this embodiment Figure 4 Based on the embodiment, a dual-injection SCR post-treatment control method is described in detail. The method is applied to the control unit 5. The method includes: S201, the control unit receives the particle concentration sent by the particle detection module.

[0057] Specifically, the content of this step is the same as that of step S101 and will not be repeated here.

[0058] S202: The control unit determines a concentration difference between a preset concentration threshold and the particle concentration.

[0059] Specifically, after the control unit 5 obtains the particle concentration detected by the particle detection module 103, the difference between the preset concentration threshold and the particle concentration is obtained as the concentration difference, so as to determine the target opening of the airflow direction valve according to the concentration difference.

[0060] S203. If the absolute value of the concentration difference is greater than or equal to the first concentration threshold and the sign is positive, the control unit controls the airflow direction valve to a first opening to fully connect the first processing passage and the second processing passage, and to shut off the first processing passage and the third processing passage.

[0061] Specifically, after obtaining the concentration difference, if it is detected that the absolute value of the concentration difference is greater than or equal to the first concentration threshold and the sign is positive, that is, when the particulate matter concentration is detected to be much smaller than the preset concentration threshold, the target opening of the airflow direction valve is determined to be the first opening, that is, the first opening is zero, and the airflow direction valve 4 is closed, so that the treated exhaust gas only passes through the second processing passage 2 with low back pressure when meeting the emission requirements, and does not enter the third processing passage 3, thereby avoiding the consumption of engine fuel.

[0062] S204. If the absolute value of the concentration difference is greater than or equal to the second concentration threshold and the sign is negative, the control unit controls the airflow direction valve to a second opening to fully connect the first processing path and the third processing path, and shut down the first processing path and the second processing path.

[0063] Specifically, if the absolute value of the detected concentration difference is greater than or equal to the first concentration threshold and the sign is negative, that is, when the detected particulate matter concentration is much greater than the preset concentration threshold, the target opening of the airflow direction valve 4 is determined to be a second opening, such as one hundred, to open the airflow direction valve 4, so that when the treated exhaust gas does not meet the emission requirements, it only passes through the third processing passage 3 and does not enter the second processing passage 2. The SCR catalyst and / or ASC catalyst in the second DPF module 301 in the third processing passage 3 is used to process and reduce the nitrogen oxides in the exhaust gas again, and the ammonia substances in the exhaust gas are captured, so as to further process the nitrogen oxides, ammonia substances and particulate matter remaining in the exhaust gas, thereby further reducing the amount of pollutants in the exhaust gas.

[0064] S205. If the absolute value of the concentration difference is between the first concentration threshold and the second concentration threshold, the control unit controls the airflow direction valve to a third opening to partially connect the first processing passage and the third processing passage, and partially connect the first processing passage and the second processing passage.

[0065] Specifically, when the particulate matter concentration is detected to be in the preset concentration threshold interval, that is, when the absolute value of the concentration difference is between the first concentration threshold and the second concentration threshold, if the particulate matter concentration is detected to be between the preset concentration threshold and the first concentration threshold, that is, when the sign is positive, the target opening of the airflow direction valve 4 is controlled to be a third opening such as thirty, so that the gas passing through the third processing passage 3 is less than the gas passing through the second processing passage 2, that is, most of the treated exhaust gas passes through the second processing passage 2 with low back pressure, and a small part of the exhaust gas passes through the third processing passage 3 for further processing.

[0066] Furthermore, if it is detected that the particulate matter concentration is between the second concentration threshold and the preset concentration threshold, that is, when the sign is negative, the target opening of the airflow direction valve 4 is controlled to be a fourth opening, such as seventy, so that the gas passing through the third processing passage 3 is more than the gas passing through the second processing passage 2, that is, most of the treated exhaust gas passes through the second DPF module 301 in the third processing passage 3, so as to further process the nitrogen oxides, ammonia substances and particulate matter remaining in the exhaust gas, thereby further reducing the amount of pollutants in the exhaust gas.

[0067] Furthermore, of course, the corresponding preset opening can also be queried in the concentration opening mapping table according to the particle concentration, wherein the concentration opening mapping table is pre-associated with and stores the openings of the airflow direction valve 4 corresponding to different particle concentrations.

[0068] The embodiment of the present application provides a dual-injection SCR post-treatment control method, which realizes preliminary treatment of the exhaust gas discharged by the engine through each selective catalytic reducer, diesel oxidation catalyst and particulate trap in the first treatment channel of the dual-injection SCR post-treatment system, and then controls the opening of the airflow direction valve through the control unit according to the concentration of particulate matter in the treated exhaust gas, and distributes the treated exhaust gas flow to the second treatment channel or the third treatment channel. When the number of particulate matter emissions does not exceed the standard, the second treatment channel with low back pressure is selected, and when there is a risk of exceeding the standard, the third treatment channel with low emissions is selected, thereby reducing fuel consumption losses as much as possible on the basis of ensuring that the particulate matter emissions meet the standard, thereby improving the economy of the engine.

[0069] An embodiment of the present application also provides a vehicle, comprising the above-mentioned dual-injection SCR after-treatment system.

[0070] Finally, it should be noted that those skilled in the art will readily conceive of other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. The present invention is intended to cover any variations, uses or adaptations of the present invention, which follow the general principles of the present invention and include common knowledge or customary technical means in the art not disclosed by the present invention, are not limited to the precise structure described above and shown in the drawings, and may be modified and changed in various ways without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

1. A dual-injection SCR post-treatment control system, characterized in that: include: A dual-injection SCR post-treatment system, an airflow direction valve and a control unit, wherein the dual-injection SCR post-treatment system comprises: a first processing passage, a second processing passage and a third processing passage, wherein the first processing passage comprises: a first DPF module, a first SCR module and a particle detection module in sequence, the second processing passage comprises a pipeline, and the third processing passage comprises a second DPF module; The output end of the first processing path, the input end of the second processing path, and the input end of the third processing path are connected via an airflow direction valve, and the airflow direction valve is communicatively connected to the control unit. The control unit is used to control the opening of the airflow direction valve according to the particle size concentration sent by the particle detection module to adjust the ratio of gas passing through the second processing path and the third processing path.

2. The dual-injection SCR post-treatment control system according to claim 1 is characterized in that: The second processing passage is provided with a silencer module for eliminating exhaust emission noise.

3. The dual-injection SCR post-treatment control system according to claim 1 is characterized in that: The second processing passage is provided with a cooling module for cooling the tail gas.

4. The dual-injection SCR post-treatment control system according to claim 1, characterized in that: The second DPF module is coated with an SCR catalyst and / or an ASC catalyst.

5. The dual-injection SCR post-treatment control system according to any one of claims 1 to 4, characterized in that: The first processing path also includes: a DOC module located before the first DPF module; and / or, a second SCR module located before the DOC module; and / or, an ASC module integrated with the first SCR module; and / or, An electric heating module located before the DOC module.

6. The dual-injection SCR post-treatment control system according to claim 5, characterized in that: The first DPF module is coated with an oxidative catalyst.

7. The dual-injection SCR post-treatment control system according to claim 5, characterized in that: The first DPF module is coated with an SCR catalyst.

8. A dual-injection SCR post-treatment control method, characterized in that: The dual-injection SCR post-treatment control system applied to any one of claims 1 to 7 comprises: The control unit receives the particle concentration sent by the particle detection module; The control unit determines the target opening of the airflow direction valve according to the magnitude relationship between the particle concentration and a preset concentration threshold; The control unit controls the airflow directional valve according to the target opening degree of the airflow directional valve.

9. The method according to claim 8, characterized in that The control unit determines the target opening of the airflow direction valve according to the magnitude relationship between the particle concentration and a preset concentration threshold, including: The control unit determines a concentration difference between a preset concentration threshold and the particle concentration; The control unit determines a target opening of the airflow direction valve according to the absolute value and sign of the concentration difference.

10. The method according to claim 9, characterized in that The control unit determines the target opening of the airflow direction valve according to the absolute value and sign of the concentration difference, including: If the absolute value of the concentration difference is greater than or equal to a first concentration threshold value and the sign is positive, the control unit controls the airflow direction valve to a first opening to fully connect the first processing passage and the second processing passage, and to shut off the first processing passage and the third processing passage; If the absolute value of the concentration difference is greater than or equal to a second concentration threshold value, and the sign is negative, the control unit controls the airflow direction valve to a second opening degree to fully connect the first processing passage and the third processing passage, and shut off the first processing passage and the second processing passage; If the absolute value of the concentration difference is between the first concentration threshold and the second concentration threshold, the control unit controls the airflow direction valve to a third opening to partially connect the first processing passage and the third processing passage, and partially connect the first processing passage and the second processing passage, and when the sign is positive, the gas passing through the third processing passage is less than the gas passing through the second processing passage, and when the sign is negative, the gas passing through the third processing passage is more than the gas passing through the second processing passage.

11. A vehicle, characterized in that: include: A dual-injection SCR post-treatment control system as claimed in any one of claims 1 to 7.

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