Method, device, storage medium and electronic equipment for controlling a three-way catalyst

Abstract

The application provides a control method and device of a three-way catalyst, a storage medium and an electronic device. The method comprises: obtaining a preset conversion efficiency value; obtaining a first actual conversion efficiency, which is an actual value of the conversion efficiency of the three-way catalyst under a current operating condition and based on an initial lambda modulation parameter; in a case where the first actual conversion efficiency is less than the preset conversion efficiency value, adjusting the lambda modulation parameter of the three-way catalyst to obtain an adjusted lambda modulation parameter; and controlling the three-way catalyst to operate by using the adjusted lambda modulation parameter, so as to improve the conversion efficiency of the three-way catalyst. The method actively adjusts the lambda modulation parameter when the conversion efficiency of the three-way catalyst is lower than the preset value, and continuously optimizes the modulation parameter in the aging process of the catalyst, so as to ensure the emission consistency of the three-way catalyst.

Description

Technical Field

[0001] This application relates to the field of three-way catalytic converter parameter adjustment, and more specifically, to a control method for a three-way catalytic converter, a control device for a three-way catalytic converter, a computer-readable storage medium, and an electronic device. Background Technology

[0002] Currently, natural gas engines generally use the "equivalent combustion + three-way catalytic converter" technology to treat exhaust gases. The three-way catalytic converter can convert carbon monoxide, hydrocarbons and NOx into CO2, H2O and N2. However, during the long-term operation of natural gas engines, the three-way catalytic converter will gradually experience hydrothermal aging due to being in a high-temperature and water-rich environment for a long time, which will lead to emission deterioration and the problem of pollutant emissions exceeding the standard. Summary of the Invention

[0003] The main objective of this application is to provide a control method, a control device, a computer-readable storage medium, and an electronic device for a three-way catalytic converter, so as to at least solve the problem that the prior art three-way catalytic converter is prone to hydrothermal aging, which leads to excessive pollutant emissions.

[0004] To achieve the above objectives, according to one aspect of this application, a control method for a three-way catalytic converter is provided. The method includes: obtaining a preset conversion efficiency value, wherein when the conversion efficiency of the three-way catalytic converter is the preset conversion efficiency value, the emissions of the engine meet emission standards or meet emission standards with a margin; obtaining a first actual conversion efficiency, wherein the first actual conversion efficiency is the actual value of the conversion efficiency of the three-way catalytic converter under current operating conditions based on initial lambda modulation parameters; when the first actual conversion efficiency is less than the preset conversion efficiency value, adjusting the lambda modulation parameters of the three-way catalytic converter to obtain adjusted lambda modulation parameters; and controlling the operation of the three-way catalytic converter using the adjusted lambda modulation parameters to improve the conversion efficiency of the three-way catalytic converter.

[0005] Optionally, when the first actual conversion efficiency is less than the preset conversion efficiency value, adjusting the lambda modulation parameter of the three-way catalytic converter to obtain the adjusted lambda modulation parameter includes: gradually adjusting the lambda modulation parameter in a preset direction with a fixed step size to obtain the adjusted lambda modulation parameter, wherein the preset direction is the direction of increasing or decreasing the lambda modulation parameter; when the conversion efficiency of the three-way catalytic converter at the current moment is greater than the conversion efficiency of the three-way catalytic converter at the previous moment, continuing to gradually adjust the lambda modulation parameter in the preset direction with the fixed step size, wherein the absolute value of the difference between the lambda modulation parameter at the current moment and the lambda modulation parameter at the previous moment is equal to one fixed step size; when the conversion efficiency of the three-way catalytic converter at the current moment is less than or equal to the conversion efficiency of the three-way catalytic converter at the previous moment, gradually adjusting the lambda modulation parameter in a non-preset direction with the fixed step size, wherein the preset direction and the non-preset direction are opposite directions.

[0006] Optionally, when the first actual conversion efficiency is less than the preset conversion efficiency value, after adjusting the lambda modulation parameter of the three-way catalytic converter to obtain the adjusted lambda modulation parameter, the method further includes: when the second actual conversion efficiency is greater than the first actual conversion efficiency, and the second actual conversion efficiency is less than or equal to the preset conversion efficiency value, writing a correction amount into a stable operating condition MAP table, wherein the second actual conversion efficiency is the actual value of the conversion efficiency of the three-way catalytic converter under the current operating condition based on the adjusted lambda modulation parameter, and the correction amount is the difference between the adjusted lambda modulation parameter and the initial lambda modulation parameter; and when the second actual conversion efficiency is greater than the preset conversion efficiency value, writing the correction amount into a full operating condition MAP table.

[0007] Optionally, when the first actual conversion efficiency is less than the preset conversion efficiency value, the lambda modulation parameter of the three-way catalytic converter is adjusted to obtain the adjusted lambda modulation parameter, including: setting a maximum number of adjustments, wherein the maximum number of adjustments is at least one; when the actual number of adjustments is two, namely the first adjustment case and the second adjustment case, the adjusted lambda modulation parameter under the first operating condition is determined as the sum of the initial lambda modulation parameter, the first correction amount, and the second correction amount, and the adjusted lambda modulation parameter under the second operating condition is determined as the sum of the initial lambda modulation parameter and the first correction amount; Wherein, the first adjustment condition is when the second actual conversion efficiency is greater than the preset conversion efficiency value, the second adjustment condition is when the second actual conversion efficiency is greater than the first actual conversion efficiency and less than or equal to the preset conversion efficiency value, the first correction amount is the correction amount of the lambda modulation parameter under the first adjustment condition, the second correction amount is the correction amount of the lambda modulation parameter under the second adjustment condition, the first operating condition is when the operating parameters of the engine and the operating parameters of the three-way catalytic converter are both within the preset range, and the second operating condition is when at least one of the operating parameters of the engine and the operating parameters of the three-way catalytic converter is not within the preset range.

[0008] Optionally, obtaining the first actual conversion efficiency includes: obtaining the operating parameters of the engine, wherein the operating parameters of the engine include at least one of the following: engine speed, engine speed change rate, engine intake charge, engine intake charge change rate, engine coolant temperature, and engine exhaust mass; obtaining the operating parameters of the three-way catalytic converter, wherein the operating parameters of the three-way catalytic converter include at least one of the following: the mass of each gas output by the three-way catalytic converter and the temperature of the three-way catalytic converter; and obtaining the first actual conversion efficiency when both the engine operating parameters and the three-way catalytic converter operating parameters are within a preset range.

[0009] Optionally, obtaining the first actual conversion efficiency includes: obtaining a primary exhaust physical model and a secondary exhaust physical model, wherein the input of the primary exhaust physical model is the engine's operating parameters, the output of the primary exhaust physical model is the engine's primary exhaust, the output of the primary exhaust physical model is the input of the secondary exhaust physical model, and the output of the secondary exhaust physical model is the engine's secondary exhaust, wherein the engine's primary exhaust is the mass of pollutants in the emissions not treated by the three-way catalytic converter, and the engine's secondary exhaust is the mass of pollutants in the final exhaust gas emitted by the engine; combining the primary exhaust physical model and the secondary exhaust physical model, determining a three-way catalytic converter physical model, wherein the input of the three-way catalytic converter physical model is the engine's primary exhaust, and the output of the three-way catalytic converter physical model is the engine's secondary exhaust; and determining the first actual conversion efficiency based on the three-way catalytic converter physical model, wherein the first actual conversion efficiency is the ratio of the pollutant difference to the engine's primary exhaust, and the pollutant difference is the difference between the engine's primary exhaust and the engine's secondary exhaust.

[0010] Optionally, obtaining the original exhaust physical model includes: acquiring multiple sets of training data, each set of training data including: historical operating parameters of the engine and the historical original exhaust of the engine corresponding to the historical operating parameters of the engine, wherein the historical operating parameters of the engine include at least one of the following: engine speed, engine intake charge, and engine temperature; training with the multiple sets of training data to obtain the original exhaust physical model; obtaining the tail exhaust physical model includes: acquiring the ideal gas law, mass conservation equation, energy conservation equation, and chemical reaction rate equation; determining the tail exhaust physical model based on the ideal gas law, the mass conservation equation, the energy conservation equation, and the chemical reaction rate equation.

[0011] According to another aspect of this application, a control device for a three-way catalytic converter is provided. The device includes: a first acquisition unit, configured to acquire a preset conversion efficiency value, wherein when the conversion efficiency of the three-way catalytic converter is the preset conversion efficiency value, the emissions of the engine meet the emission standards or meet the emission standards with a margin; a second acquisition unit, configured to acquire a first actual conversion efficiency, wherein the first actual conversion efficiency is the actual value of the conversion efficiency of the three-way catalytic converter under the current operating condition based on an initial lambda modulation parameter; an adjustment unit, configured to adjust the lambda modulation parameter of the three-way catalytic converter when the first actual conversion efficiency is less than the preset conversion efficiency value, to obtain an adjusted lambda modulation parameter; and a control unit, configured to control the operation of the three-way catalytic converter using the adjusted lambda modulation parameter to improve the conversion efficiency of the three-way catalytic converter.

[0012] According to another aspect of this application, a computer-readable storage medium is provided, the computer-readable storage medium including a stored program, wherein, when the program is executed, it controls the device where the computer-readable storage medium is located to perform any of the control methods for the three-way catalytic converter described above.

[0013] According to another aspect of this application, an electronic device is provided, comprising: one or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the one or more programs including a control method for performing any of the three-way catalytic converters described above.

[0014] Applying the technical solution of this application, the above-mentioned control method for a three-way catalytic converter first obtains a preset value for conversion efficiency. When the conversion efficiency of the three-way catalytic converter is at the preset value, the engine emissions meet the emission standards or meet the emission standards with a margin. Then, it obtains a first actual conversion efficiency, which is the actual value of the conversion efficiency of the three-way catalytic converter under the current operating conditions based on the initial lambda modulation parameters. Next, when the first actual conversion efficiency is less than the preset value, it adjusts the lambda modulation parameters of the three-way catalytic converter to obtain the adjusted lambda modulation parameters. Finally, it uses the adjusted lambda modulation parameters to control the operation of the three-way catalytic converter to improve its conversion efficiency. This method, based on the conversion efficiency of the three-way catalytic converter, actively adjusts the lambda modulation parameters when the conversion efficiency is lower than the preset value. During the aging process of the catalytic converter, the modulation parameters are continuously optimized, thereby ensuring the emission consistency of the three-way catalytic converter and solving the problem in the prior art where three-way catalytic converters are prone to hydrothermal aging, leading to excessive pollutant emissions. Attached Figure Description

[0015] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings:

[0016] Figure 1 A hardware structure block diagram of a mobile terminal for performing a control method for a three-way catalytic converter according to an embodiment of this application is shown;

[0017] Figure 2 A schematic flowchart of a control method for a three-way catalytic converter according to an embodiment of this application is shown;

[0018] Figure 3 A schematic diagram of CH4 emissions according to an embodiment of this application is shown;

[0019] Figure 4 A schematic diagram of NOx emissions according to an embodiment of this application is shown;

[0020] Figure 5 A schematic flowchart of another control method for a three-way catalytic converter according to an embodiment of this application is shown;

[0021] Figure 6 A schematic flowchart of another control method for a three-way catalytic converter according to an embodiment of this application is shown;

[0022] Figure 7 A structural block diagram of a control device for a three-way catalytic converter provided according to an embodiment of this application is shown.

[0023] The above figures include the following reference numerals:

[0024] 102. Processor; 104. Memory; 106. Transmission device; 108. Input / output device. Detailed Implementation

[0025] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0026] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0027] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this application described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0028] For ease of description, the following explains some of the nouns or terms used in the embodiments of this application:

[0029] Three-way catalytic converter (TWC): The most important external purification device installed in the vehicle exhaust system. It can convert harmful gases such as carbon monoxide, nitrogen oxides and unburned hydrocarbons in vehicle exhaust into harmless carbon dioxide, water and nitrogen through oxidation and reduction, effectively purifying vehicle exhaust.

[0030] Lambda modulation: A modulated wave superimposed on the demand for fuel gas. Proper lambda modulation can optimize emissions.

[0031] As described in the background section, in the prior art, the three-way catalytic converter is in a high-temperature, water-vapor-rich environment for a long time, which will gradually lead to hydrothermal aging and thus deterioration of emissions. In order to solve the problem that the three-way catalytic converter is prone to hydrothermal aging and causes pollutant emissions to exceed the standard in the prior art, the embodiments of this application provide a three-way catalytic converter control method, a three-way catalytic converter control device, a computer-readable storage medium, and an electronic device.

[0032] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0033] The methods and embodiments provided in this application can be executed on a mobile terminal, computer terminal, or similar computing device. Taking running on a mobile terminal as an example, Figure 1 This is a hardware structure block diagram of a mobile terminal for a control method of a three-way catalytic converter according to an embodiment of the present invention. Figure 1 As shown, a mobile terminal may include one or more ( Figure 1 Only one is shown in the diagram. A processor 102 (which may include, but is not limited to, a microprocessor MCU or a programmable logic device FPGA, etc.) and a memory 104 for storing data are also shown. The mobile terminal may further include a transmission device 106 for communication functions and an input / output device 108. Those skilled in the art will understand that... Figure 1 The structure shown is for illustrative purposes only and does not limit the structure of the mobile terminal described above. For example, the mobile terminal may also include components that are more... Figure 1 The more or fewer components shown, or having the same Figure 1 The different configurations shown.

[0034] The memory 104 can be used to store computer programs, such as application software programs and modules, like the computer program corresponding to the three-way catalytic converter control method in this embodiment of the invention. The processor 102 executes various functional applications and data processing by running the computer program stored in the memory 104, thereby implementing the above-described method. The memory 104 may include high-speed random access memory and non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some instances, the memory 104 may further include memory remotely located relative to the processor 102, and these remote memories can be connected to the mobile terminal via a network. Examples of the aforementioned networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof. The transmission device 106 is used to receive or send data via a network. Specific examples of the aforementioned networks may include wireless networks provided by the mobile terminal's communication provider. In one example, the transmission device 106 includes a network interface controller (NIC), which can be connected to other network devices via a base station to communicate with the Internet. In one example, the transmission device 106 may be a radio frequency (RF) module, which is used to communicate with the Internet wirelessly.

[0035] This embodiment provides a method that runs on a mobile terminal, computer terminal, or similar computing device. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Also, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0036] Figure 2 This is a flowchart of a control method for a three-way catalytic converter according to an embodiment of this application. Figure 2 As shown, the three-way catalytic converter is installed inside the engine, and the method includes the following steps:

[0037] Step S201: Obtain a preset value for conversion efficiency. When the conversion efficiency of the three-way catalytic converter is the preset value, the emissions of the engine meet the emission standards or meet the emission standards with a margin.

[0038] Specifically, the three-way catalytic converter is the most important external purification device installed in the vehicle's exhaust system. It can convert harmful gases such as carbon monoxide, nitrogen oxides, and unburned hydrocarbons in vehicle exhaust into harmless carbon dioxide, water, and nitrogen through oxidation and reduction reactions, effectively purifying vehicle exhaust.

[0039] However, during prolonged operation of a natural gas engine, the three-way catalytic converter, constantly exposed to a high-temperature, water-vapor-rich environment, gradually undergoes hydrothermal aging, leading to emissions degradation. The preset conversion efficiency is set based on the conversion efficiency of the three-way catalytic converter under normal operating conditions (before aging occurs). For example, if the conversion efficiency of the three-way catalytic converter under normal operating conditions is 99%, the preset conversion efficiency can be set to 95%. Specific preset values ​​can be adjusted according to actual application requirements.

[0040] Step S202: Obtain the first actual conversion efficiency, which is the actual value of the conversion efficiency of the three-way catalytic converter under the current operating conditions based on the initial lambda modulation parameters.

[0041] Specifically, lambda is the excess air coefficient, which is the ratio of the actual air-fuel ratio to the stoichiometric air-fuel ratio. The lambda modulation parameter is a parameter that affects the frequency and amplitude of lambda; adjusting the lambda modulation parameter can change the frequency and amplitude of lambda. Generally, an initial lambda value and initial lambda modulation parameter are set at the engine's factory to keep lambda within a relatively small fluctuation range. However, when the three-way catalytic converter ages, continuing to use the initial lambda value and initial lambda modulation parameter can no longer meet the engine's emission requirements. Therefore, it is necessary to adjust the lambda modulation parameter to change the frequency and amplitude of lambda, thus increasing the lambda fluctuation range to adapt to the emission requirements under different operating conditions as the three-way catalytic converter ages.

[0042] The specific implementation steps for obtaining the first actual conversion efficiency are as follows:

[0043] Step S2021: Obtain the operating parameters of the engine. The operating parameters of the engine include at least one of the following: engine speed, engine speed change rate, engine intake charge, engine intake charge change rate, engine coolant temperature, and engine exhaust mass.

[0044] Step S2022: Obtain the operating parameters of the three-way catalytic converter. The operating parameters of the three-way catalytic converter include at least one of the following: the mass of each gas output by the three-way catalytic converter and the temperature of the three-way catalytic converter.

[0045] Step S2023: Under the condition that the operating parameters of the engine and the three-way catalytic converter are both within the preset range, the first actual conversion efficiency is obtained.

[0046] Specifically, by measuring the operating parameters of the engine and the three-way catalytic converter, it can be determined whether the engine is currently operating in a steady state or a transient state. If the engine is currently operating in a steady state, the lambda modulation parameter can be adjusted to avoid some parameter errors under transient conditions.

[0047] Furthermore, in practical applications, the engine's operating conditions and the three-way catalytic converter's conversion efficiency are assessed simultaneously. The preset ranges for the engine's and the three-way catalytic converter's operating parameters are set based on actual application requirements. For example, the preset range for engine speed can be 1000 rpm - 1800 rpm, the preset range for engine speed change rate can be 50 rpm - 100 rpm, the preset range for engine intake air volume can be 8% - 10%, the preset range for engine intake air volume change rate can be 3% - 5%, the preset range for engine coolant temperature can be 90℃ - 105℃, and the preset range for three-way catalytic converter temperature can be 470℃ - 560℃. Other preset ranges for engine and three-way catalytic converter operating parameters can be set based on historical data.

[0048] The specific implementation steps for obtaining the first actual conversion efficiency also include the following steps:

[0049] Step S301: Obtain the primary exhaust physical model and the exhaust physical model. The input of the primary exhaust physical model is the operating parameters of the engine. The output of the primary exhaust physical model is the primary exhaust of the engine. The output of the primary exhaust physical model is the input of the exhaust physical model. The output of the exhaust physical model is the exhaust of the engine. The primary exhaust of the engine is the mass of pollutants in the emissions that have not been treated by the three-way catalytic converter. The exhaust of the engine is the mass of pollutants in the exhaust gas finally emitted by the engine.

[0050] The specific steps for obtaining the original physical model are as follows:

[0051] Step S3011: Obtain multiple sets of training data. Each set of training data includes the historical operating parameters of the engine and the historical original output of the engine corresponding to the historical operating parameters of the engine. The historical operating parameters of the engine include at least one of the following: engine speed, engine intake charge, and engine temperature.

[0052] Step S3012: Train using multiple sets of the above training data to obtain the original physical model.

[0053] The specific steps for obtaining the tail-end physical model are as follows:

[0054] Step S3013: Obtain the ideal gas law, mass conservation equation, energy conservation equation, and chemical reaction rate equation;

[0055] Step S3014: Determine the above-mentioned tailrace physical model based on the above-mentioned ideal gas law, the above-mentioned mass conservation equation, the above-mentioned energy conservation equation and the above-mentioned chemical reaction rate equation.

[0056] Specifically, the above steps can yield accurate physical models of the primary exhaust and the exhaust, thus providing an accurate physical model of the three-way catalytic converter. This allows for a more accurate calculation of the actual conversion efficiency of the three-way catalytic converter and a more precise adjustment of the lambda modulation parameter.

[0057] Step S302: Combining the above-mentioned exhaust physical model and the above-mentioned tail exhaust physical model, determine the three-way catalytic converter physical model. The input of the above-mentioned three-way catalytic converter physical model is the exhaust of the engine, and the output of the above-mentioned three-way catalytic converter physical model is the tail exhaust of the engine.

[0058] Step S303: Based on the above-mentioned three-way catalytic converter physical model, determine the first actual conversion efficiency, which is the ratio of the pollutant difference to the original exhaust of the engine, and the pollutant difference is the difference between the original exhaust and the exhaust of the engine.

[0059] Specifically, the emission conversion efficiency is calculated based on the emission components output from the physical model of the three-way catalytic converter. Under steady-state conditions and when the conversion efficiency is below the limit, the lambda modulation parameter is actively adjusted at a fixed step size. When the conversion efficiency increases, the correction amount is learned into the steady-state correction MAP; when the conversion efficiency exceeds the set limit, the correction amount is learned into the full-condition self-learning MAP, and the steady-state correction MAP is cleared. Compared with traditional methods, the modulation parameters can be continuously optimized during the catalytic converter aging process, thereby ensuring emission consistency throughout the entire life cycle of the three-way catalytic converter.

[0060] Among them, such as Figure 3 and Figure 4 As shown, the physical model of the three-way catalytic converter outputs the component information of engine emissions. Pollutants in engine emissions include NOx, CH4, CO, and NH3, with NOx and CH4 being the most abundant components. Therefore, the three-way catalytic converter primarily targets the conversion of NOx and CH4. Figure 3 The relationship between lambda fluctuations and CH4 concentration in engine exhaust is shown. Figure 4 This relates the fluctuation of lambda to the concentration of NOx in engine exhaust. Among other things, Figure 3In the diagram, 'a' represents the actual value curve of CH4 tail emissions, and 'b' represents the model value curve of CH4 tail emissions. Figure 3 As can be seen from this, after the three-way catalytic converter undergoes hydrothermal aging, the initial lambda value can no longer meet the conversion requirements of CH4 in engine emissions. Therefore, it is necessary to control the frequency and amplitude of lambda by adjusting the lambda modulation parameters. c represents the deviation curve between the actual lambda and the set lambda (set lambda is 1), and d represents the self-learning value curve of the lambda modulation amplitude (i.e., the adjustment value of the lambda amplitude). The magnitude of the lambda modulation amplitude can be seen more intuitively from the two curves c and d. a and b are marked by the left vertical and horizontal axes, and c and d are marked by the right vertical and horizontal axes.

[0061] in, Figure 4 In the figure, 'e' represents the actual value curve of NOx tail emissions, and 'f' represents the model value curve of NOx tail emissions. Figure 4 As can be seen from this, after the three-way catalytic converter undergoes hydrothermal aging, the initial lambda value can no longer meet the conversion requirements of NOx in engine emissions. Therefore, it is necessary to control the frequency and amplitude of lambda by adjusting the lambda modulation parameters. g represents the deviation curve between the actual lambda and the set lambda (set lambda is 1), and h represents the self-learning value curve of the lambda modulation amplitude (i.e., the adjustment value of the lambda amplitude). The magnitude of the lambda modulation amplitude can be seen more intuitively from the two curves g and h. e and f are marked by the left vertical and horizontal axes, and g and h are marked by the right vertical and horizontal axes.

[0062] After the three-way catalytic converter experiences hydrothermal aging, its initial lambda value is no longer sufficient to meet the conversion requirements of NOx and CH4 in engine emissions. Therefore, it is necessary to control the frequency and amplitude of lambda by adjusting the lambda modulation parameters. When the lambda modulation parameters are adjusted to a certain value, the frequency and amplitude of lambda change accordingly, increasing the conversion efficiency of NOx and CH4, reducing the pollutant content in the engine exhaust, and meeting emission requirements. However, the relationship between the lambda amplitude and the pollutant content in the exhaust varies under different operating conditions. Figure 3 and Figure 4 The smaller the amplitude of lambda under the operating conditions shown, the less pollutant content in the exhaust. However, under other operating conditions, the larger the amplitude of lambda, the less pollutant content in the exhaust. Therefore, the relationship between the amplitude of lambda and the pollutant content in the exhaust needs to be determined based on the actual application.

[0063] Step S203: When the first actual conversion efficiency is less than the preset conversion efficiency value, adjust the lambda modulation parameter of the three-way catalytic converter to obtain the adjusted lambda modulation parameter.

[0064] Specifically, the preset conversion efficiency value is set to determine whether the three-way catalytic converter's conversion efficiency has decreased due to hydrothermal aging. If the first actual conversion efficiency is greater than or equal to the preset conversion efficiency value, it proves that the three-way catalytic converter has not aged or the aging is not severe. If the first actual conversion efficiency is less than the preset conversion efficiency value, it proves that the aging of the three-way catalytic converter has had a relatively serious impact on the engine's pollutant emissions. At this time, it is necessary to adjust the lambda modulation parameter of the three-way catalytic converter to reduce the impact of the aging of the three-way catalytic converter on the engine's pollutant emissions, improve the conversion efficiency of the three-way catalytic converter, and ensure the emission consistency of the three-way catalytic converter.

[0065] Among them, such as Figure 5 As shown, when the first actual conversion efficiency is less than the preset conversion efficiency value, the specific implementation steps for adjusting the lambda modulation parameter of the three-way catalytic converter to obtain the adjusted lambda modulation parameter are as follows:

[0066] Step S2031: The lambda modulation parameters are gradually adjusted in a preset direction with a fixed step size to obtain the adjusted lambda modulation parameters. The preset direction is either the direction of increasing the lambda modulation parameters or the direction of decreasing the lambda modulation parameters.

[0067] Step S2032: If the conversion efficiency of the three-way catalytic converter at the current moment is greater than that at the previous moment, the lambda modulation parameter is adjusted step by step in the preset direction using the fixed step size. The absolute value of the difference between the lambda modulation parameter at the current moment and the lambda modulation parameter at the previous moment is equal to one of the fixed step sizes.

[0068] Step S2033: When the conversion efficiency of the three-way catalytic converter at the current moment is less than or equal to the conversion efficiency of the three-way catalytic converter at the previous moment, the lambda modulation parameter is gradually adjusted in a non-preset direction with a fixed step size. The preset direction is opposite to the non-preset direction.

[0069] Specifically, this allows for efficient and accurate adjustment of the lambda modulation parameter, thereby rapidly improving the conversion efficiency of the three-way catalytic converter. In another embodiment, if the conversion efficiency of the three-way catalytic converter at the current moment is less than or equal to the conversion efficiency at the previous moment, the lambda modulation parameter is gradually adjusted from the initial lambda modulation parameter using the aforementioned fixed step size in a non-preset direction.

[0070] Wherein, when the first actual conversion efficiency is less than the preset conversion efficiency value, after adjusting the lambda modulation parameter of the three-way catalytic converter to obtain the adjusted lambda modulation parameter, the method further includes the following steps:

[0071] Step S401: When the second actual conversion efficiency is greater than the first actual conversion efficiency and the second actual conversion efficiency is less than or equal to the preset conversion efficiency value, the correction amount is written into the stable operating condition MAP table. The second actual conversion efficiency is the actual value of the conversion efficiency of the three-way catalytic converter under the current operating condition based on the adjusted lambda modulation parameters. The correction amount is the difference between the adjusted lambda modulation parameters and the initial lambda modulation parameters.

[0072] Step S402: If the second actual conversion efficiency is greater than the preset conversion efficiency value, the correction amount is written into the full-condition MAP table.

[0073] Specifically, this allows for the direct retrieval of lambda modulation parameter data from the stable operating condition MAP table and the full operating condition MAP table based on engine operating conditions and the conversion efficiency of the three-way catalytic converter in subsequent applications. The corresponding lambda modulation parameters can then be directly used to control the operation of the three-way catalytic converter, reducing the number of lambda modulation parameter adjustments and obtaining accurate lambda modulation parameters while minimizing computational resource waste. Furthermore, the modulation parameters can be continuously optimized during the catalytic converter's aging process, thereby ensuring consistent emissions throughout the three-way catalytic converter's entire lifecycle.

[0074] In addition, if the second actual conversion efficiency is greater than the preset conversion efficiency value, the correction amount is written into the full-condition MAP table, and the correction amount written into the steady-state correction MAP before the adjustment is completed is cleared.

[0075] In some embodiments, the lambda modulation parameter has maximum and minimum limits. The purpose of adjustment is to make the second actual conversion efficiency greater than the preset conversion efficiency value. However, in some cases, even when the lambda modulation parameter is adjusted to the maximum or minimum limit, the second actual conversion efficiency can only be greater than the first actual conversion efficiency but less than or equal to the preset conversion efficiency value, and cannot be greater than the preset conversion efficiency value. Therefore, in this case, only the correction amount is written to the stable operating condition MAP table to correct for the current operating condition. In addition, if the pollutant content in the engine exhaust is still high (above the emission limit) after adjustment, an alarm message can be issued.

[0076] The specific implementation steps for adjusting the lambda modulation parameter of the three-way catalytic converter to obtain the adjusted lambda modulation parameter when the first actual conversion efficiency is less than the preset conversion efficiency value further include the following steps:

[0077] Step S501: Set the maximum number of adjustments, where the maximum number of adjustments is at least one.

[0078] Step S502: When there are two actual adjustment times, namely the first adjustment situation and the second adjustment situation, the adjusted lambda modulation parameter under the first working condition is determined as the sum of the initial lambda modulation parameter, the first correction amount and the second correction amount, and the adjusted lambda modulation parameter under the second working condition is determined as the sum of the initial lambda modulation parameter and the first correction amount.

[0079] Wherein, the first adjustment condition is that the second actual conversion efficiency is greater than the preset conversion efficiency value, the second adjustment condition is that the second actual conversion efficiency is greater than the first actual conversion efficiency and less than or equal to the preset conversion efficiency value, the first correction amount is the correction amount of the lambda modulation parameter under the first adjustment condition, the second correction amount is the correction amount of the lambda modulation parameter under the second adjustment condition, the first operating condition is the operating condition in which the operating parameters of the engine and the operating parameters of the three-way catalytic converter are both within the preset range, and the second operating condition is the operating condition in which at least one of the operating parameters of the engine and the operating parameters of the three-way catalytic converter is not within the preset range.

[0080] Specifically, this allows for a clear distinction between steady-state and transient corrections, enabling different degrees of correction for each state, thereby improving correction accuracy, increasing the conversion efficiency of the three-way catalytic converter, and continuously optimizing the modulation parameters during the aging process of the catalytic converter, thus ensuring consistent emissions throughout the entire lifecycle of the three-way catalytic converter.

[0081] Step S204: The operation of the three-way catalytic converter is controlled by the above-adjusted lambda modulation parameters to improve the conversion efficiency of the three-way catalytic converter.

[0082] Specifically, the emission conversion efficiency is calculated based on the emission components output from the physical model of the three-way catalytic converter. Under steady-state conditions and when the conversion efficiency is below the limit, the lambda modulation parameter is actively adjusted at a fixed step size. When the conversion efficiency increases, the correction amount is learned into the steady-state correction MAP; when the conversion efficiency exceeds the set limit, the correction amount is learned into the full-condition self-learning MAP, and the steady-state correction MAP is cleared. Compared with traditional methods, the modulation parameters can be continuously optimized during the catalytic converter aging process, thereby ensuring the emission consistency of the three-way catalytic converter.

[0083] The control method for the three-way catalytic converter described in this application first obtains a preset conversion efficiency value. When the conversion efficiency of the three-way catalytic converter is at the preset value, the engine emissions meet the emission standards or meet the emission standards with a margin. Then, it obtains a first actual conversion efficiency, which is the actual value of the conversion efficiency of the three-way catalytic converter under the current operating conditions based on the initial lambda modulation parameters. Next, when the first actual conversion efficiency is less than the preset conversion efficiency value, the lambda modulation parameters of the three-way catalytic converter are adjusted to obtain the adjusted lambda modulation parameters. Finally, the adjusted lambda modulation parameters are used to control the operation of the three-way catalytic converter to improve its conversion efficiency. This method, based on the conversion efficiency of the three-way catalytic converter, actively adjusts the lambda modulation parameters when the conversion efficiency is lower than the preset value. It continuously optimizes the modulation parameters during the aging process of the catalytic converter, thereby ensuring the emission consistency of the three-way catalytic converter and solving the problem of excessive pollutant emissions caused by hydrothermal aging of the three-way catalytic converter in the prior art.

[0084] To enable those skilled in the art to better understand the technical solution of this application, the implementation process of the control method of the three-way catalytic converter of this application will be described in detail below with reference to specific embodiments.

[0085] This embodiment relates to a specific control method for a three-way catalytic converter, such as... Figure 6 As shown, it includes the following steps:

[0086] Step S1: Calculate the real-time conversion efficiency of the three-way catalytic converter based on the physical model of the three-way catalytic converter;

[0087] Step S2: When the real-time conversion efficiency of the three-way catalytic converter is lower than the efficiency limit, actively adjust the lambda modulation parameter step by step according to a fixed step size;

[0088] Step S3: After the first adjustment, determine whether the conversion efficiency has improved. If it has improved, continue to adjust the lambda modulation parameter in the same direction. If it has not improved, start from the initial lambda modulation parameter and adjust the lambda modulation parameter in the opposite direction.

[0089] Step S4: Determine whether the conversion efficiency of the three-way catalytic converter after adjustment is higher than that of the three-way catalytic converter before adjustment. If the conversion efficiency of the three-way catalytic converter after adjustment is higher than that of the three-way catalytic converter before adjustment but lower than the efficiency limit, learn the correction amount into the steady-state correction MAP. If the conversion efficiency of the three-way catalytic converter after adjustment is higher than the efficiency limit, learn the correction amount into the full-condition correction MAP, and clear the correction amount written into the steady-state correction MAP before the adjustment is completed.

[0090] It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases the steps shown or described may be executed in a different order than that shown here.

[0091] This application also provides a control device for a three-way catalytic converter. It should be noted that the control device for the three-way catalytic converter in this application can be used to execute the control method for the three-way catalytic converter provided in this application. This device is used to implement the above embodiments and preferred embodiments; details already described will not be repeated. As used below, the term "module" can refer to a combination of software and / or hardware that performs a predetermined function. Although the device described in the following embodiments is preferably implemented in software, hardware implementation, or a combination of software and hardware, is also possible and contemplated.

[0092] The control device for the three-way catalytic converter provided in the embodiments of this application is described below.

[0093] Figure 7 This is a schematic diagram of the control device for a three-way catalytic converter according to an embodiment of this application. Figure 7As shown, a three-way catalytic converter is installed inside the engine. The device includes a first acquisition unit 10, a second acquisition unit 20, an adjustment unit 30, and a control unit 40. The first acquisition unit 10 is used to acquire a preset conversion efficiency value. When the conversion efficiency of the three-way catalytic converter is the preset conversion efficiency value, the emissions of the engine meet the emission standards or meet the emission standards with a margin. The second acquisition unit 20 is used to acquire a first actual conversion efficiency, which is the actual value of the conversion efficiency of the three-way catalytic converter under the current operating conditions based on the initial lambda modulation parameters. The adjustment unit 30 is used to adjust the lambda modulation parameters of the three-way catalytic converter when the first actual conversion efficiency is less than the preset conversion efficiency value, to obtain the adjusted lambda modulation parameters. The control unit 40 is used to control the operation of the three-way catalytic converter using the adjusted lambda modulation parameters to improve the conversion efficiency of the three-way catalytic converter.

[0094] The control device for the three-way catalytic converter described in this application includes a first acquisition unit, a second acquisition unit, an adjustment unit, and a control unit. The first acquisition unit is used to acquire a preset conversion efficiency value. When the conversion efficiency of the three-way catalytic converter is the preset conversion efficiency value, the emissions of the engine meet the emission standards or meet the emission standards with a margin. The second acquisition unit is used to acquire a first actual conversion efficiency, which is the actual value of the conversion efficiency of the three-way catalytic converter under the current operating conditions based on the initial lambda modulation parameters. The adjustment unit is used to adjust the lambda modulation parameters of the three-way catalytic converter when the first actual conversion efficiency is less than the preset conversion efficiency value, to obtain the adjusted lambda modulation parameters. The control unit is used to control the operation of the three-way catalytic converter using the adjusted lambda modulation parameters to improve the conversion efficiency of the three-way catalytic converter. Based on the conversion efficiency of the three-way catalytic converter, the device actively adjusts the lambda modulation parameter when the conversion efficiency of the three-way catalytic converter is lower than the preset value. During the aging process of the catalytic converter, the modulation parameter is continuously optimized to ensure the emission consistency of the three-way catalytic converter. This solves the problem that the existing three-way catalytic converter is prone to hydrothermal aging, which leads to excessive pollutant emissions.

[0095] In one optional embodiment, the adjustment unit includes a first adjustment module, a second adjustment module, and a third adjustment module. The first adjustment module is used to gradually adjust the lambda modulation parameter in a preset direction with a fixed step size to obtain the adjusted lambda modulation parameter. The preset direction is either the direction of increasing or decreasing the lambda modulation parameter. The second adjustment module is used to continue gradually adjusting the lambda modulation parameter in the preset direction with the fixed step size when the conversion efficiency of the three-way catalytic converter at the current moment is greater than that at the previous moment. The absolute value of the difference between the lambda modulation parameter at the current moment and that at the previous moment is equal to one of the fixed step sizes. The third adjustment module is used to gradually adjust the lambda modulation parameter in a non-preset direction with the fixed step size when the conversion efficiency of the three-way catalytic converter at the current moment is less than or equal to that at the previous moment. The preset direction and the non-preset direction are opposite. This allows for efficient and accurate adjustment of the lambda modulation parameter, thereby rapidly improving the conversion efficiency of the three-way catalytic converter.

[0096] In an optional embodiment, the above-mentioned device further includes a first processing module and a second processing module. The first processing module is used to adjust the lambda modulation parameter of the three-way catalytic converter when the first actual conversion efficiency is less than the preset conversion efficiency value. After obtaining the adjusted lambda modulation parameter, when the second actual conversion efficiency is greater than the first actual conversion efficiency and the second actual conversion efficiency is less than or equal to the preset conversion efficiency value, the correction amount is written into the stable operating condition MAP table. The second actual conversion efficiency is the actual value of the conversion efficiency of the three-way catalytic converter under the current operating condition based on the adjusted lambda modulation parameter, and the correction amount is the difference between the adjusted lambda modulation parameter and the initial lambda modulation parameter. The second processing module is used to write the correction amount into the full operating condition MAP table when the second actual conversion efficiency is greater than the preset conversion efficiency value. In subsequent applications, the corresponding lambda modulation parameter data from the stable operating condition MAP table and the full operating condition MAP table can be directly retrieved based on the engine operating conditions and the conversion efficiency of the three-way catalytic converter. The corresponding lambda modulation parameters can then be directly used to control the operation of the three-way catalytic converter, reducing the number of lambda modulation parameter adjustments and obtaining accurate lambda modulation parameters while minimizing computational resource waste. The modulation parameters can be continuously optimized during the catalytic converter's aging process, thereby ensuring emission consistency throughout the entire lifecycle of the three-way catalytic converter.

[0097] For example, the adjustment unit includes a third processing module and a first determining module. The third processing module is used to set a maximum number of adjustments, wherein the maximum number of adjustments is at least one. The first determining module is used to determine the adjusted lambda modulation parameter under the first operating condition as the sum of the initial lambda modulation parameter, the first correction amount, and the second correction amount, respectively, when the actual number of adjustments is two, namely a first adjustment situation and a second adjustment situation; and to determine the adjusted lambda modulation parameter under the second operating condition as the sum of the initial lambda modulation parameter and the first correction amount; wherein the first adjustment situation is the sum of the second adjustment situation. The actual conversion efficiency is greater than the preset conversion efficiency value. The second adjustment condition is when the second actual conversion efficiency is greater than the first actual conversion efficiency and less than or equal to the preset conversion efficiency value. The first correction amount is the correction amount of the lambda modulation parameter under the first adjustment condition, and the second correction amount is the correction amount of the lambda modulation parameter under the second adjustment condition. The first operating condition is when the operating parameters of the engine and the three-way catalytic converter are both within the preset range. The second operating condition is when at least one of the operating parameters of the engine and the three-way catalytic converter is not within the preset range. This allows for a clear distinction between steady-state and transient correction amounts, with different degrees of correction applied to both, improving correction accuracy and the conversion efficiency of the three-way catalytic converter. Continuous optimization of the modulation parameters during catalytic converter aging ensures consistent emissions throughout the entire lifecycle of the three-way catalytic converter.

[0098] In this embodiment, the second acquisition unit includes a first acquisition module, a second acquisition module, and a third acquisition module. The first acquisition module is used to acquire the operating parameters of the engine, which include at least one of the following: engine speed, engine speed change rate, engine intake charge, engine intake charge change rate, engine coolant temperature, and engine exhaust mass. The second acquisition module is used to acquire the operating parameters of the three-way catalytic converter, which include at least one of the following: the mass of each gas output by the three-way catalytic converter and the temperature of the three-way catalytic converter. The third acquisition module is used to acquire the first actual conversion efficiency when both the engine operating parameters and the three-way catalytic converter operating parameters are within a preset range. It can be determined whether the engine's current operating condition is a steady-state condition or a transient condition. When the engine's current operating condition is a steady-state condition, the lambda modulation parameter adjustment begins, which can avoid some parameter errors under transient conditions.

[0099] In one optional embodiment, the second acquisition unit further includes a fourth acquisition module, a second determination module, and a third determination module. The fourth acquisition module is used to acquire the primary exhaust physical model and the exhaust physical model. The input of the primary exhaust physical model is the operating parameters of the engine, the output of the primary exhaust physical model is the primary exhaust of the engine, the output of the primary exhaust physical model is the input of the exhaust physical model, and the output of the exhaust physical model is the exhaust of the engine. The primary exhaust of the engine is the mass of pollutants in the emissions that have not been treated by the three-way catalytic converter, and the exhaust of the engine is the mass of pollutants in the exhaust gas finally emitted by the engine. The second determination module is used to combine the primary exhaust physical model and the exhaust physical model to determine the three-way catalytic converter physical model. The input of the three-way catalytic converter physical model is the primary exhaust of the engine, and the output of the three-way catalytic converter physical model is the exhaust of the engine. The third determination module is used to determine the first actual conversion efficiency based on the three-way catalytic converter physical model. The first actual conversion efficiency is the ratio of the pollutant difference to the primary exhaust of the engine, and the pollutant difference is the difference between the primary exhaust and the exhaust of the engine. Compared with traditional methods, the modulation parameters can be continuously optimized during the aging process of the catalyst, thereby ensuring the emission consistency of the three-way catalytic converter throughout its entire life cycle.

[0100] As an optional solution, the fourth acquisition module includes a first acquisition submodule, a training submodule, a second acquisition submodule, and a determination submodule. The first acquisition submodule is used to acquire multiple sets of training data. Each set of training data includes historical operating parameters of the engine and the corresponding historical exhaust gas of the engine acquired within a historical time period. The historical operating parameters of the engine include at least one of the following: engine speed, engine intake charge, and engine temperature. The training submodule is used to train using the multiple sets of training data to obtain the exhaust gas physical model. The second acquisition submodule is used to acquire the ideal gas law, mass conservation equation, energy conservation equation, and chemical reaction rate equation. The determination submodule is used to determine the exhaust gas physical model based on the ideal gas law, mass conservation equation, energy conservation equation, and chemical reaction rate equation. This allows for the acquisition of accurate exhaust gas and exhaust gas physical models, thereby obtaining an accurate three-way catalytic converter physical model. This makes the calculated actual conversion efficiency of the three-way catalytic converter more accurate and the adjustment of the lambda modulation parameter more accurate.

[0101] The control device for the aforementioned three-way catalytic converter includes a processor and a memory. The first acquisition unit and other components are stored as program units in the memory, and the processor executes these program units to achieve the corresponding functions. All of the above modules reside in the same processor; alternatively, the modules may be located in different processors in any combination.

[0102] The processor contains a kernel, which retrieves the corresponding program unit from memory. One or more kernels can be configured, and adjusting kernel parameters can address the problem of hydrothermal aging in existing three-way catalytic converters, which leads to excessive pollutant emissions.

[0103] The memory may include non-permanent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM, and the memory includes at least one memory chip.

[0104] This invention provides a computer-readable storage medium including a stored program, wherein, when the program is executed, it controls the device containing the computer-readable storage medium to perform the control method for the three-way catalytic converter.

[0105] Specifically, the control methods for three-way catalytic converters include:

[0106] Step S201: Obtain a preset value for conversion efficiency. When the conversion efficiency of the three-way catalytic converter is the preset value, the emissions of the engine meet the emission standards or meet the emission standards with a margin.

[0107] Specifically, the three-way catalytic converter is the most important external purification device installed in the vehicle's exhaust system. It can convert harmful gases such as carbon monoxide, nitrogen oxides, and unburned hydrocarbons in vehicle exhaust into harmless carbon dioxide, water, and nitrogen through oxidation and reduction reactions, effectively purifying vehicle exhaust.

[0108] Step S202: Obtain the first actual conversion efficiency, which is the actual value of the conversion efficiency of the three-way catalytic converter under the current operating conditions based on the initial lambda modulation parameters.

[0109] Specifically, lambda is the excess air coefficient, which is the ratio of the actual air-fuel ratio to the stoichiometric air-fuel ratio. The lambda modulation parameter is a parameter that affects the frequency and amplitude of lambda; adjusting the lambda modulation parameter can change the frequency and amplitude of lambda. Generally, an initial lambda value and initial lambda modulation parameter are set at the engine's factory to keep lambda within a relatively small fluctuation range. However, when the three-way catalytic converter ages, continuing to use the initial lambda value and initial lambda modulation parameter can no longer meet the engine's emission requirements. Therefore, it is necessary to adjust the lambda modulation parameter to change the frequency and amplitude of lambda, thus increasing the lambda fluctuation range to adapt to the emission requirements under different operating conditions as the three-way catalytic converter ages.

[0110] Step S203: When the first actual conversion efficiency is less than the preset conversion efficiency value, adjust the lambda modulation parameter of the three-way catalytic converter to obtain the adjusted lambda modulation parameter.

[0111] Specifically, the preset conversion efficiency value is set to determine whether the three-way catalytic converter's conversion efficiency has decreased due to hydrothermal aging. If the first actual conversion efficiency is greater than or equal to the preset conversion efficiency value, it proves that the three-way catalytic converter has not aged or the aging is not severe. If the first actual conversion efficiency is less than the preset conversion efficiency value, it proves that the aging of the three-way catalytic converter has had a relatively serious impact on the engine's pollutant emissions. At this time, it is necessary to adjust the lambda modulation parameter of the three-way catalytic converter to reduce the impact of the aging of the three-way catalytic converter on the engine's pollutant emissions, improve the conversion efficiency of the three-way catalytic converter, and ensure the emission consistency of the three-way catalytic converter.

[0112] This invention provides a processor for running a program, wherein the program executes the control method for the three-way catalytic converter.

[0113] Specifically, the control methods for three-way catalytic converters include:

[0114] Step S201: Obtain a preset value for conversion efficiency. When the conversion efficiency of the three-way catalytic converter is the preset value, the emissions of the engine meet the emission standards or meet the emission standards with a margin.

[0115] Specifically, the three-way catalytic converter is the most important external purification device installed in the vehicle's exhaust system. It can convert harmful gases such as carbon monoxide, nitrogen oxides, and unburned hydrocarbons in vehicle exhaust into harmless carbon dioxide, water, and nitrogen through oxidation and reduction reactions, effectively purifying vehicle exhaust.

[0116] Step S202: Obtain the first actual conversion efficiency, which is the actual value of the conversion efficiency of the three-way catalytic converter under the current operating conditions based on the initial lambda modulation parameters.

[0117] Specifically, lambda is the excess air coefficient, which is the ratio of the actual air-fuel ratio to the stoichiometric air-fuel ratio. The lambda modulation parameter is a parameter that affects the frequency and amplitude of lambda; adjusting the lambda modulation parameter can change the frequency and amplitude of lambda. Generally, an initial lambda value and initial lambda modulation parameter are set at the engine's factory to keep lambda within a relatively small fluctuation range. However, when the three-way catalytic converter ages, continuing to use the initial lambda value and initial lambda modulation parameter can no longer meet the engine's emission requirements. Therefore, it is necessary to adjust the lambda modulation parameter to change the frequency and amplitude of lambda, thus increasing the lambda fluctuation range to adapt to the emission requirements under different operating conditions as the three-way catalytic converter ages.

[0118] Step S203: When the first actual conversion efficiency is less than the preset conversion efficiency value, adjust the lambda modulation parameter of the three-way catalytic converter to obtain the adjusted lambda modulation parameter.

[0119] Specifically, the preset conversion efficiency value is set to determine whether the three-way catalytic converter's conversion efficiency has decreased due to hydrothermal aging. If the first actual conversion efficiency is greater than or equal to the preset conversion efficiency value, it proves that the three-way catalytic converter has not aged or the aging is not severe. If the first actual conversion efficiency is less than the preset conversion efficiency value, it proves that the aging of the three-way catalytic converter has had a relatively serious impact on the engine's pollutant emissions. At this time, it is necessary to adjust the lambda modulation parameter of the three-way catalytic converter to reduce the impact of the aging of the three-way catalytic converter on the engine's pollutant emissions, improve the conversion efficiency of the three-way catalytic converter, and ensure the emission consistency of the three-way catalytic converter.

[0120] This invention provides a device including a processor, a memory, and a program stored in the memory and executable on the processor. When the processor executes the program, it performs at least the following steps:

[0121] Step S201: Obtain a preset value for conversion efficiency. When the conversion efficiency of the three-way catalytic converter is the preset value, the emissions of the engine meet the emission standards or meet the emission standards with a margin.

[0122] Step S202: Obtain the first actual conversion efficiency, which is the actual value of the conversion efficiency of the three-way catalytic converter under the current operating conditions based on the initial lambda modulation parameters.

[0123] Step S203: When the first actual conversion efficiency is less than the preset conversion efficiency value, adjust the lambda modulation parameter of the three-way catalytic converter to obtain the adjusted lambda modulation parameter.

[0124] The devices mentioned in this article can be servers, PCs, tablets, mobile phones, etc.

[0125] This application also provides a computer program product, which, when executed on a data processing device, is suitable for executing an initialization program having at least the following method steps:

[0126] Step S201: Obtain a preset value for conversion efficiency. When the conversion efficiency of the three-way catalytic converter is the preset value, the emissions of the engine meet the emission standards or meet the emission standards with a margin.

[0127] Step S202: Obtain the first actual conversion efficiency, which is the actual value of the conversion efficiency of the three-way catalytic converter under the current operating conditions based on the initial lambda modulation parameters.

[0128] Step S203: When the first actual conversion efficiency is less than the preset conversion efficiency value, adjust the lambda modulation parameter of the three-way catalytic converter to obtain the adjusted lambda modulation parameter.

[0129] It is obvious to those skilled in the art that the modules or steps of the present invention described above can be implemented using general-purpose computing devices. They can be centralized on a single computing device or distributed across a network of multiple computing devices. They can be implemented using computer-executable program code, and thus can be stored in a storage device for execution by a computing device. In some cases, the steps shown or described can be performed in a different order than those described herein, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. Thus, the present invention is not limited to any particular combination of hardware and software.

[0130] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0131] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0132] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0133] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0134] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0135] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0136] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0137] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0138] As can be seen from the above description, the embodiments of this application achieve the following technical effects:

[0139] 1) The control method for the three-way catalytic converter described in this application first obtains a preset value for conversion efficiency. When the conversion efficiency of the three-way catalytic converter is at the preset value, the engine emissions meet the emission standards or meet the emission standards with a margin. Then, a first actual conversion efficiency is obtained, which is the actual value of the conversion efficiency of the three-way catalytic converter under the current operating conditions based on the initial lambda modulation parameters. Next, when the first actual conversion efficiency is less than the preset value, the lambda modulation parameters of the three-way catalytic converter are adjusted to obtain the adjusted lambda modulation parameters. Finally, the adjusted lambda modulation parameters are used to control the operation of the three-way catalytic converter to improve its conversion efficiency. This method actively adjusts the lambda modulation parameters based on the conversion efficiency of the three-way catalytic converter. When the conversion efficiency of the three-way catalytic converter is lower than the preset value, the modulation parameters are continuously optimized during the aging process of the catalytic converter, thereby ensuring the emission consistency of the three-way catalytic converter and solving the problem in the prior art where the three-way catalytic converter is prone to hydrothermal aging, leading to excessive pollutant emissions.

[0140] 2) The control device for the three-way catalytic converter of this application includes a first acquisition unit, a second acquisition unit, an adjustment unit, and a control unit. The first acquisition unit is used to acquire a preset value of conversion efficiency. When the conversion efficiency of the three-way catalytic converter is the preset value, the emissions of the engine meet the emission standards or meet the emission standards with a margin. The second acquisition unit is used to acquire a first actual conversion efficiency, which is the actual value of the conversion efficiency of the three-way catalytic converter under the current operating conditions based on the initial lambda modulation parameters. The adjustment unit is used to adjust the lambda modulation parameters of the three-way catalytic converter when the first actual conversion efficiency is less than the preset value, to obtain the adjusted lambda modulation parameters. The control unit is used to control the operation of the three-way catalytic converter using the adjusted lambda modulation parameters to improve the conversion efficiency of the three-way catalytic converter. Based on the conversion efficiency of the three-way catalytic converter, the device actively adjusts the lambda modulation parameter when the conversion efficiency of the three-way catalytic converter is lower than the preset value. During the aging process of the catalytic converter, the modulation parameter is continuously optimized to ensure the emission consistency of the three-way catalytic converter. This solves the problem that the existing three-way catalytic converter is prone to hydrothermal aging, which leads to excessive pollutant emissions.

[0141] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A control method for a three-way catalytic converter, characterized in that, The method includes: Obtain a preset value for conversion efficiency. When the conversion efficiency of the three-way catalytic converter is the preset value, the engine's emissions meet the emission standards or meet the emission standards with a margin. Obtain the first actual conversion efficiency, which is the actual value of the conversion efficiency of the three-way catalytic converter under the current operating conditions based on the initial lambda modulation parameters. When the first actual conversion efficiency is less than the preset conversion efficiency value, the lambda modulation parameter of the three-way catalytic converter is adjusted to obtain the adjusted lambda modulation parameter. This includes: gradually adjusting the lambda modulation parameter in a preset direction with a fixed step size to obtain the adjusted lambda modulation parameter, wherein the preset direction is either the direction of increasing or decreasing the lambda modulation parameter; when the conversion efficiency of the three-way catalytic converter at the current moment is greater than the conversion efficiency of the three-way catalytic converter at the previous moment, the lambda modulation parameter is further gradually adjusted in the preset direction with the fixed step size, wherein the absolute value of the difference between the lambda modulation parameter at the current moment and the lambda modulation parameter at the previous moment is equal to one fixed step size; when the conversion efficiency of the three-way catalytic converter at the current moment is less than or equal to the conversion efficiency of the three-way catalytic converter at the previous moment, the lambda modulation parameter is gradually adjusted in a non-preset direction with the fixed step size, wherein the preset direction and the non-preset direction are opposite directions. The operation of the three-way catalytic converter is controlled by the adjusted lambda modulation parameters to improve the conversion efficiency of the three-way catalytic converter; Obtaining the first actual conversion efficiency includes: obtaining the operating parameters of the engine, wherein the operating parameters of the engine include at least one of the following: engine speed, engine speed change rate, engine intake charge, engine intake charge change rate, engine coolant temperature, and engine exhaust mass; obtaining the operating parameters of the three-way catalytic converter, wherein the operating parameters of the three-way catalytic converter include at least one of the following: the mass of each gas output by the three-way catalytic converter and the temperature of the three-way catalytic converter; and obtaining the first actual conversion efficiency when both the engine operating parameters and the three-way catalytic converter operating parameters are within a preset range.

2. The control method according to claim 1, characterized in that, When the first actual conversion efficiency is less than the preset conversion efficiency value, after adjusting the lambda modulation parameter of the three-way catalytic converter to obtain the adjusted lambda modulation parameter, the method further includes: If the second actual conversion efficiency is greater than the first actual conversion efficiency, and the second actual conversion efficiency is less than or equal to the preset conversion efficiency value, the correction amount is written into the stable operating condition MAP table. The second actual conversion efficiency is the actual value of the conversion efficiency of the three-way catalytic converter under the current operating condition based on the adjusted lambda modulation parameters. The correction amount is the difference between the adjusted lambda modulation parameters and the initial lambda modulation parameters. If the second actual conversion efficiency is greater than the preset conversion efficiency value, the correction amount is written into the full-condition MAP table.

3. The control method according to claim 2, characterized in that, When the first actual conversion efficiency is less than the preset conversion efficiency value, the lambda modulation parameter of the three-way catalytic converter is adjusted to obtain the adjusted lambda modulation parameter, including: Set a maximum number of adjustments, wherein the maximum number of adjustments is at least one; When there are two actual adjustment times, namely the first adjustment situation and the second adjustment situation, the adjusted lambda modulation parameter under the first working condition is determined as the sum of the initial lambda modulation parameter, the first correction amount and the second correction amount, and the adjusted lambda modulation parameter under the second working condition is determined as the sum of the initial lambda modulation parameter and the first correction amount. Wherein, the first adjustment condition is when the second actual conversion efficiency is greater than the preset conversion efficiency value, the second adjustment condition is when the second actual conversion efficiency is greater than the first actual conversion efficiency and less than or equal to the preset conversion efficiency value, the first correction amount is the correction amount of the lambda modulation parameter under the first adjustment condition, the second correction amount is the correction amount of the lambda modulation parameter under the second adjustment condition, the first operating condition is when the operating parameters of the engine and the operating parameters of the three-way catalytic converter are both within the preset range, and the second operating condition is when at least one of the operating parameters of the engine and the operating parameters of the three-way catalytic converter is not within the preset range.

4. The control method according to claim 1, characterized in that, To obtain the first actual conversion efficiency, including: Obtain the primary exhaust physical model and the exhaust physical model. The input of the primary exhaust physical model is the operating parameters of the engine, and the output of the primary exhaust physical model is the primary exhaust of the engine. The output of the primary exhaust physical model is the input of the exhaust physical model, and the output of the exhaust physical model is the exhaust of the engine. The primary exhaust of the engine is the mass of pollutants in the emissions that have not been treated by the three-way catalytic converter, and the exhaust of the engine is the mass of pollutants in the exhaust gas finally emitted by the engine. By combining the exhaust physical model and the tail exhaust physical model, the three-way catalytic converter physical model is determined. The input of the three-way catalytic converter physical model is the exhaust of the engine, and the output of the three-way catalytic converter physical model is the tail exhaust of the engine. Based on the physical model of the three-way catalytic converter, the first actual conversion efficiency is determined. The first actual conversion efficiency is the ratio of the pollutant difference to the original exhaust of the engine, where the pollutant difference is the difference between the original exhaust and the exhaust of the engine.

5. The control method according to claim 4, characterized in that, Obtain the original physical model, including: Multiple sets of training data are acquired, and each set of training data includes the historical operating parameters of the engine and the historical original output of the engine corresponding to the historical operating parameters, acquired within a historical time period. The historical operating parameters of the engine include at least one of the following: engine speed, engine intake air volume, and engine temperature. The original physical model is obtained by training with multiple sets of the aforementioned training data. Obtain the tail-end physical model, including: Obtain the ideal gas law, the mass conservation equation, the energy conservation equation, and the chemical reaction rate equation; The tailrace physical model is determined based on the ideal gas law, the mass conservation equation, the energy conservation equation, and the chemical reaction rate equation.

6. A control device for a three-way catalytic converter, characterized in that, The control device controls the three-way catalytic converter using the control method for the three-way catalytic converter according to any one of claims 1 to 5, and the device includes: The first acquisition unit is used to acquire a preset value of conversion efficiency. When the conversion efficiency of the three-way catalytic converter is the preset value of conversion efficiency, the engine's emissions meet the emission standards or meet the emission standards with a margin. The second acquisition unit is used to acquire the first actual conversion efficiency, which is the actual value of the conversion efficiency of the three-way catalytic converter under the current operating conditions based on the initial lambda modulation parameters. An adjustment unit is used to adjust the lambda modulation parameter of the three-way catalytic converter when the first actual conversion efficiency is less than the preset value of the conversion efficiency, so as to obtain the adjusted lambda modulation parameter. A control unit is used to control the operation of the three-way catalytic converter using the adjusted lambda modulation parameters to improve the conversion efficiency of the three-way catalytic converter.

7. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes a stored program, wherein, when the program is executed, it controls the device containing the computer-readable storage medium to perform the control method for the three-way catalytic converter according to any one of claims 1 to 5.

8. An electronic device, characterized in that, include: One or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the one or more programs including a control method for performing a three-way catalytic converter according to any one of claims 1 to 5.

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