A method and system for exhaust control of a twin-engine

Abstract

The application relates to the field of engine exhaust treatment technology, in particular to an exhaust control method and system of a double-engine, wherein the method comprises the following steps: constructing an engine performance model; acquiring working condition parameters of N engines; inputting the working condition parameters of the N engines into the engine performance model to obtain exhaust emissions of i kinds of pollutants; and determining an exhaust treatment strategy according to the exhaust emissions of each kind of pollutant. The engine performance model constructed by the application can acquire the working condition parameters of multiple engines, perform parallel calculation on exhaust emissions of the multiple engines, quickly calculate the mass of various pollutants in the exhaust, and then control corresponding treatment modules of an exhaust treatment system according to the types of the pollutants. The exhaust control method of the application can control the exhaust treatment system to simultaneously perform exhaust treatment on multiple engines, thereby reducing the cost of exhaust treatment.

Description

Technical Field

[0001] This application relates to the field of engine exhaust gas treatment technology, and in particular to a dual-engine exhaust control method and system. Background Technology

[0002] To control vehicle emissions, China has established the sixth stage emission standard for motor vehicles, which requires that engine exhaust emissions not exceed the pollutant emission limits. Engine exhaust pollutants mainly include nitrogen oxides, carbon monoxide, hydrocarbons, and particulate matter.

[0003] Therefore, in order to reduce the content of pollutants in exhaust gases, an exhaust aftertreatment system needs to be installed in the engine's exhaust system. Modules such as DPF, SCR, DOC, and ASC in the exhaust aftertreatment system can treat different types of pollutants respectively.

[0004] Special vehicles, such as sanitation vehicles and cranes, are generally equipped with two engines: a main engine to drive the vehicle and an auxiliary engine to drive the operation. Therefore, existing special vehicles need to be equipped with two separate exhaust gas treatment systems to treat the exhaust gases from the two engines respectively.

[0005] However, the low load on the main engine of special vehicles during operation can lead to the following two problems:

[0006] (1) The exhaust temperature of the main engine is low, which causes the SCR to fail to reach the operating temperature, and the exhaust gas treatment system cannot effectively filter nitrogen oxides.

[0007] (2) Incomplete combustion in the engine leads to an increase in carbon particles, and the low exhaust temperature prevents the carbon soot in the DPF from being regenerated, ultimately causing the DPF to become clogged.

[0008] To avoid the aforementioned problems in the exhaust gas treatment system of special vehicles, this application provides a dual-engine exhaust control method and system. Summary of the Invention

[0009] To overcome the problems existing in related technologies, the first aspect of this application provides a dual-engine exhaust control method, comprising:

[0010] Construct an engine performance model; the engine performance model is used to calculate the exhaust emissions of N engines under different operating conditions.

[0011] Obtain the operating parameters of N engines;

[0012] By inputting the operating parameters of N engines into the engine performance model, the exhaust emissions of i pollutants are obtained.

[0013] The exhaust gas treatment strategy is determined based on the exhaust gas emission amount of each pollutant; N is an integer greater than or equal to 2, and i is an integer greater than or equal to 1.

[0014] In one implementation, the engine performance model specifically includes:

[0015]

[0016] m i =k i ×Q mew

[0017] Among them, Q mew Q represents the exhaust gas flow rate of N engines. mew,n m represents the exhaust emission flow rate of the nth engine. i k represents the exhaust emission of the i-th pollutant in the total exhaust emissions. i This represents the emission factor of the i-th pollutant.

[0018] In one implementation, determining an exhaust gas treatment strategy based on the exhaust gas emission amount of each pollutant includes:

[0019] Obtain nitrogen oxide emissions;

[0020] The urea injection rate is determined based on the nitrogen oxide emissions.

[0021] Control the SCR to inject urea in the aftertreatment pipeline.

[0022] In one implementation, determining an exhaust gas treatment strategy based on the exhaust gas emission amount of each pollutant includes:

[0023] Obtain the pressure difference between the intake and exhaust sides of the DPF;

[0024] Determine whether the pressure difference is greater than or equal to a preset pressure threshold. If yes, perform DPF regeneration; otherwise, continue to monitor the pressure difference.

[0025] In one implementation, the DPF regeneration specifically includes:

[0026] The carbon loading of the DPF is calculated based on the pressure difference between the inlet and outlet sides of the DPF.

[0027] The temperature of exhaust gases emitted by the engine is controlled based on carbon load.

[0028] The second aspect of this application provides a dual-engine exhaust control system that executes the steps of the exhaust control method described in this application under the control of an electronic control unit;

[0029] The exhaust control system includes an aftertreatment pipe and N intake pipes;

[0030] The N intake pipes are respectively connected to the exhaust ports of the N engines. The aftertreatment pipe is equipped with an exhaust gas treatment unit and an exhaust gas detection unit. The exhaust gas treatment unit and the exhaust gas detection unit are respectively connected to the electronic control unit.

[0031] The exhaust gas detection unit is used to detect exhaust parameters and send them to the electronic control unit;

[0032] The exhaust gas treatment unit is used to treat exhaust gas.

[0033] The electronic control unit is used to control the exhaust gas detection unit and the exhaust gas treatment unit.

[0034] In one embodiment, the air outlet of the air inlet pipe is provided with a one-way valve.

[0035] In one embodiment, the air intake pipe is provided with an insulation layer.

[0036] In one embodiment, the exhaust gas treatment unit includes a DOC module, a DPF module, and an SCR module.

[0037] In one embodiment, the exhaust gas detection unit includes a differential pressure sensor and two nitrogen oxide sensors;

[0038] The differential pressure sensor is installed at both ends of the DPF module and is used to measure the back pressure of the DPF module;

[0039] The two nitrogen oxide sensors are respectively installed at the inlet and outlet of the aftertreatment pipeline, and the nitrogen oxide sensors are used to detect the nitrogen oxide concentration before and after exhaust gas treatment.

[0040] The technical solution provided in this application may include the following beneficial effects:

[0041] The engine performance model constructed in this application can acquire operating parameters of multiple engines, perform parallel calculations on the exhaust gases emitted by multiple engines, quickly calculate the mass of various pollutants in the exhaust gases, and then control the corresponding processing modules of the exhaust gas treatment system according to the type of pollutant. The exhaust control method of this application can control the exhaust gas treatment system to treat the exhaust gases of multiple engines simultaneously, reducing the cost of exhaust gas treatment.

[0042] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0043] The above and other objects, features and advantages of this application will become more apparent from the more detailed description of exemplary embodiments thereof in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments thereof.

[0044] Figure 1 This is a schematic flowchart of the exhaust control method shown in the embodiments of this application;

[0045] Figure 2 This is a structural diagram of the exhaust control system shown in an embodiment of this application. Detailed Implementation

[0046] Preferred embodiments of the present application will now be described in more detail with reference to the accompanying drawings. While preferred embodiments of the present application are shown in the drawings, it should be understood that the present application may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to make the present application more thorough and complete, and to fully convey the scope of the present application to those skilled in the art.

[0047] The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The singular forms “a,” “the,” and “the” used in this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0048] It should be understood that although the terms "first," "second," "third," etc., may be used in this application to describe various information, this information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, without departing from the scope of this application, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0049] Example 1

[0050] Existing special vehicles are generally equipped with two separate exhaust gas treatment systems to treat the exhaust gases of the two engines respectively. This exhaust gas treatment method currently has two drawbacks. First, during operation, the main engine load is low and the exhaust temperature is low, which causes the SCR to not reach its operating temperature or optimal operating temperature. Second, incomplete combustion in the main engine leads to an increase in carbon particles, which can easily cause the DPF to become clogged.

[0051] This application provides an exhaust control method, which is implemented through the exhaust gas treatment system of a special vehicle.

[0052] Unlike existing exhaust gas treatment systems, the exhaust gas treatment system in this application embodiment has an air inlet connected to the exhaust gas outlets of N engines, and uses a single exhaust gas treatment system to treat the exhaust gases of the main engine and auxiliary engine.

[0053] The exhaust control method in the embodiments of this application is as follows: Figure 1 As shown, it includes the following steps:

[0054] S1. Construct an engine performance model;

[0055] Specifically, the engine performance model is used to calculate the exhaust emissions of N engines under different operating conditions.

[0056] It is understood that the engine performance model is a deep learning-based network model or a mathematical simulation model.

[0057] S2. Obtain the operating parameters of N engines;

[0058] S3. Input the operating parameters of N engines into the engine performance model to obtain the exhaust emissions of i pollutants.

[0059] S4. Determine the exhaust gas treatment strategy based on the exhaust gas emission amount of each pollutant; N is an integer greater than or equal to 2, and i is an integer greater than or equal to 1.

[0060] Specifically, in step S1, the engine performance model includes:

[0061]

[0062] m i =k i ×Q mew

[0063] Among them, Q mew Q represents the exhaust gas flow rate of N engines. mew,n m represents the exhaust emission flow rate of the nth engine. i k represents the exhaust emission of the i-th pollutant in the total exhaust emissions. i This represents the emission factor of the i-th pollutant.

[0064] The exhaust gas treatment system in this embodiment includes a DOC (Digital Oxide Charge), a DPF (Digital Fluid Filter), and an SCR (Self-Reducing Catalytic Reduction). The DOC converts carbon monoxide and hydrocarbons emitted from the diesel engine into harmless carbon dioxide and water through a catalytic oxidation reaction. The DPF filters particulate matter. The SCR injects urea to reduce nitrogen oxides.

[0065] Furthermore, step S4 specifically includes:

[0066] Obtain nitrogen oxide emissions;

[0067] The urea injection rate is determined based on the nitrogen oxide emissions.

[0068] Control the SCR to inject urea in the aftertreatment pipeline.

[0069] To ensure the filtration efficiency of the DPF, the carbon loading of the DPF needs to be monitored in real time. If the carbon loading of the DPF reaches a preset threshold, the DPF will be regenerated.

[0070] Furthermore, step S4 specifically includes:

[0071] Obtain the pressure difference between the intake and exhaust sides of the DPF;

[0072] Determine whether the pressure difference is greater than or equal to a preset pressure threshold. If yes, perform DPF regeneration; otherwise, continue to monitor the pressure difference.

[0073] The carbon loading of the DPF is calculated based on the pressure difference between the inlet and outlet sides of the DPF.

[0074] The temperature of exhaust gases emitted by the engine is controlled based on carbon load.

[0075] The engine performance model constructed in this application embodiment can acquire operating parameters of multiple engines, perform parallel calculations on the exhaust gases emitted by multiple engines, quickly calculate the mass of various pollutants in the exhaust gases, and then control the corresponding processing modules of the exhaust gas treatment system according to the type of pollutant. Therefore, the exhaust control method can control the exhaust gas treatment system to treat the exhaust gases of multiple engines simultaneously, reducing the cost of exhaust gas treatment.

[0076] Example 2

[0077] This application provides a dual-engine exhaust control system that executes the steps of the exhaust control method described in Embodiment 1 under the control of an electronic control unit.

[0078] The exhaust control system shown in the embodiments of this application is as follows: Figure 2 As shown, it includes an after-treatment pipe and N intake pipes.

[0079] Specifically, the N intake pipes are respectively connected to the exhaust ports of the N engines, and the aftertreatment pipes are equipped with an exhaust gas treatment unit and an exhaust gas detection unit. The exhaust gas treatment unit and the exhaust gas detection unit are respectively communicatively connected to the electronic control unit.

[0080] The exhaust gas detection unit is used to detect exhaust parameters and send them to the electronic control unit; the exhaust gas treatment unit is used to treat exhaust gas; the electronic control unit is used to control the exhaust gas detection unit and the exhaust gas treatment unit.

[0081] In drive mode, to prevent exhaust gas backflow between intake pipes, one-way valves are installed at the outlets of the intake pipes.

[0082] Because multiple engines share a single exhaust gas treatment system, the length of the intake duct needs to be extended. To prevent the exhaust gas temperature from dropping, the intake duct is equipped with an insulation layer.

[0083] Specifically, the exhaust gas treatment unit includes a DOC module, a DPF module, and an SCR module.

[0084] Specifically, the exhaust gas detection unit includes a differential pressure sensor and two nitrogen oxide sensors. The differential pressure sensor is located at both ends of the DPF module and is used to measure the back pressure of the DPF module; the two nitrogen oxide sensors are respectively located at the inlet and outlet of the aftertreatment pipeline, and are used to detect the nitrogen oxide concentration before and after exhaust gas treatment.

[0085] The exhaust control system shown in this embodiment connects to the exhaust ports of multiple engines through an intake pipe, and collects the exhaust gas in the aftertreatment pipeline for processing, thereby reducing the number of exhaust gas treatment components and lowering equipment costs.

[0086] Regarding the apparatus in the above embodiments, the specific manner in which each module performs its operation has been described in detail in the embodiments concerning the apparatus in the above embodiments, and will not be elaborated further here.

[0087] The solution of this application has been described in detail above with reference to the accompanying drawings. In the above embodiments, the descriptions of each embodiment have different emphases; parts not described in detail in a certain embodiment can be referred to in the relevant descriptions of other embodiments. Those skilled in the art should also understand that the actions and modules involved in the specification are not necessarily essential to this application.

[0088] Furthermore, it is understood that the steps in the method of this application embodiment can be adjusted, merged, or deleted in order according to actual needs, and the modules in the device of this application embodiment can be merged, divided, or deleted according to actual needs.

[0089] Furthermore, the method according to this application can also be implemented as a computer program or computer program product, which includes computer program code instructions for performing some or all of the steps in the method described above.

[0090] Alternatively, this application may be implemented as a non-transitory machine-readable storage medium (or computer-readable storage medium, or machine-readable storage medium) storing executable code (or computer program, or computer instruction code) that, when executed by a processor of an electronic device (or electronic device, server, etc.), causes the processor to perform some or all of the steps of the methods described above according to this application.

[0091] Those skilled in the art will also understand that the various exemplary logic blocks, modules, circuits, and algorithm steps described in connection with the present application can be implemented as electronic hardware, computer software, or a combination of both.

[0092] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems and methods according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0093] The various embodiments of this application have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or improvement of the technology in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A method for exhaust control of dual engines, characterized in that, include: Construct an engine performance model; The engine performance model is used to calculate the exhaust emissions of N engines under different operating conditions. The engine performance model specifically includes: in, This represents the exhaust gas flow rate of N engines. This represents the exhaust gas flow rate of the nth engine. This represents the exhaust emission of the i-th pollutant in the total exhaust emissions. Represents the emission factor of the i-th pollutant; Obtain the operating parameters of N engines; After inputting the operating parameters of N engines into the engine performance model, the exhaust emissions of i pollutants are calculated in parallel. The exhaust gas treatment strategy is determined based on the exhaust gas emission amount of each pollutant; N is 2, and i is an integer greater than or equal to 1.

2. The exhaust control method for a dual-engine system according to claim 1, characterized in that, Determine an exhaust gas treatment strategy based on the exhaust gas emission volume of each pollutant, including: Obtain nitrogen oxide emissions; The urea injection rate is determined based on the nitrogen oxide emissions. Control the SCR to inject urea in the aftertreatment pipeline.

3. The exhaust control method for a dual-engine system according to claim 2, characterized in that, Determine an exhaust gas treatment strategy based on the exhaust gas emission volume of each pollutant, including: Obtain the pressure difference between the intake and exhaust sides of the DPF; Determine whether the pressure difference is greater than or equal to a preset pressure threshold. If yes, perform DPF regeneration; otherwise, continue to monitor the pressure difference.

4. The exhaust control method for a dual-engine system according to claim 3, characterized in that, The DPF regeneration specifically includes: The carbon loading of the DPF is calculated based on the pressure difference between the inlet and outlet sides of the DPF. The temperature of exhaust gases emitted by the engine is controlled based on carbon load.

5. A dual-engine exhaust control system, characterized in that, The steps of the exhaust control method according to any one of claims 1 to 4 are executed under the control of the electronic control unit. The exhaust control system includes an aftertreatment pipe and N intake pipes; The N intake pipes are respectively connected to the exhaust ports of the N engines. The aftertreatment pipe is equipped with an exhaust gas treatment unit and an exhaust gas detection unit. The exhaust gas treatment unit and the exhaust gas detection unit are respectively connected to the electronic control unit. The exhaust gas detection unit is used to detect exhaust parameters and send them to the electronic control unit; The exhaust gas treatment unit is used to treat exhaust gas. The electronic control unit is used to control the exhaust gas detection unit and the exhaust gas treatment unit.

6. The exhaust control system for a dual-engine system according to claim 5, characterized in that, The air outlet of the air inlet pipe is equipped with a one-way valve.

7. The exhaust control system for a dual-engine system according to claim 6, characterized in that, The air intake pipe is equipped with an insulation layer.

8. The exhaust control system for a dual-engine system according to claim 5, characterized in that, The exhaust gas treatment unit includes a DOC module, a DPF module, and an SCR module.

9. The exhaust control system for a dual-engine system according to claim 8, characterized in that, The exhaust gas detection unit includes a differential pressure sensor and two nitrogen oxide sensors; The differential pressure sensor is installed at both ends of the DPF module and is used to measure the back pressure of the DPF module; The two nitrogen oxide sensors are respectively installed at the inlet and outlet of the aftertreatment pipeline, and the nitrogen oxide sensors are used to detect the nitrogen oxide concentration before and after exhaust gas treatment.

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