A method for controlling exhaust gas treatment

Abstract

The present invention discloses an exhaust gas treatment control method, comprising: detecting and acquiring pre- and post-treatment NOx emission concentrations, and determining a target NOx emission ratio at the inlet of the post-treatment device and a specific NOx emission ratio based on the pre- and post-treatment NOx emission concentrations; determining a combustion mode coefficient request value and an actual combustion mode coefficient value based on the target NOx emission ratio and the specific NOx emission ratio at the inlet of the post-treatment device; determining a final output combustion mode set value based on the request and actual combustion mode coefficient values; determining a combustion mode interpolation, an air-fuel ratio interpolation, a fuel rail pressure interpolation, an injection angle interpolation, and an ignition angle interpolation based on the final output combustion mode set value; and using the air-fuel ratio interpolation, fuel rail pressure interpolation, injection angle interpolation, and ignition angle interpolation to control engine combustion. The present invention fully utilizes the advantages of lean fuel consumption and reduces the emission risks caused by lean combustion.

Description

Technical Field

[0001] The present invention relates to the field of engine control, and in particular to an exhaust gas treatment control method. Background Art

[0002] Driven by energy-saving, emission-reduction, and fuel-efficiency regulations, and with the increasing penetration of hybrid vehicles, gasoline engines with higher thermal efficiency are increasingly sought after by major OEMs. Lean burn, a combustion process in which the air-fuel ratio is greater than the stoichiometric ratio (14.7:1), improves the adiabatic index of the mixture, reduces combustion temperatures, and suppresses knock, making it an effective technology for achieving high thermal efficiency. Lean burn not only improves fuel economy but also reduces CO, H₂, and CH₃ emissions. However, when the mixture is too lean, the catalytic activity of the traditional gasoline engine aftertreatment system, the Three-Way Catalyst (TWC), against NOx, decreases dramatically, leading to increased NOx emissions.

[0003] Chinese patent CN115773170A discloses a lean-burn gasoline engine NOx emission after-treatment device and control method. In this method, an exhaust gas recirculation device is installed downstream of the engine and connected to the engine's air intake. A liquid-cooled nanostructured reactor (LNT) is installed downstream of the exhaust gas recirculation device. A four-way catalytic converter (FTC) is installed downstream of the LNT device. A passive SCR (SCR) is installed downstream of the FTC. The above-mentioned prior art has the following drawbacks: the required after-treatment device is relatively complex and costly. The model requires precise calculation of the NH3 and NOx adsorption values ​​in the catalyst, which is difficult to achieve. Furthermore, the model only has two combustion modes: rich burn and lean burn, which fails to fully utilize the advantages of lean burn.

[0004] Chinese patent CN117514422A discloses an exhaust gas treatment device and exhaust gas treatment control method. When the engine is in a lean-burn state, the generated ammonia reacts with the original NOx in the SCR to produce N2 and H2O, thereby reducing NOx emissions. The above-mentioned prior art has the following drawbacks: it requires precise calculation of the amount of NH3 entering the TWC and the amount of NH3 stored in the catalyst, which are affected by numerous factors. It does not consider the varying post-treatment characteristics resulting from product tolerances across batches, nor the impact of different fuel grades on the emission model. This makes the model difficult to accurately estimate and apply in practice. Furthermore, it only has two combustion modes: rich burn and lean burn, which fails to fully utilize the advantages of lean burn. Summary of the Invention

[0005] The object of the present invention is to provide a tail gas treatment control method to reduce emission risks.

[0006] To solve the above technical problems, the present invention provides an exhaust gas treatment control method, comprising:

[0007] Detecting and obtaining the NOx emission concentration before and after post-treatment, and determining the NOx target ratio emission at the inlet of the post-treatment device and the NOx ratio emission at the inlet of the post-treatment device based on the NOx emission concentration before and after post-treatment;

[0008] Determining a combustion mode coefficient request value and an actual combustion mode coefficient value based on a target NOx emission ratio at an after-treatment device inlet and a NOx emission ratio at an after-treatment device inlet;

[0009] Determine the final output combustion mode setting value according to the combustion mode coefficient request value and the combustion mode coefficient actual value;

[0010] The combustion mode interpolation, air-fuel ratio interpolation, fuel rail pressure interpolation, injection angle interpolation, and ignition angle interpolation are determined according to the final output combustion mode setting value; the air-fuel ratio interpolation, fuel rail pressure interpolation, injection angle interpolation, and ignition angle interpolation are used to control engine combustion.

[0011] According to the above scheme, the method for determining the target NOx emission ratio and the NOx emission ratio at the inlet of the post-treatment device according to the NOx emission concentration before post-treatment and the NOx emission concentration after post-treatment includes:

[0012] The NOx emission concentration before and after post-treatment is read by the post-treatment sensor;

[0013] Filtering the NOx emission concentration before post-treatment and the NOx emission concentration after post-treatment respectively to obtain a filtered value of the NOx emission concentration before post-treatment and a filtered value of the NOx emission concentration after post-treatment;

[0014] Determine the NOx flow rate at the inlet of the post-treatment device and the NOx flow rate at the outlet of the post-treatment device according to the filtered value of the NOx emission concentration before post-treatment and the filtered value of the NOx emission concentration after post-treatment;

[0015] Based on the engine power, determine the cumulative work of the engine during the running time;

[0016] Determine the accumulated NOx flow rate at the inlet of the post-treatment device and the accumulated NOx flow rate at the outlet of the post-treatment device according to the NOx flow rate at the inlet of the post-treatment device and the NOx flow rate at the outlet of the post-treatment device;

[0017] When the accumulated work or operating time reaches their respective limits, the specific NOx emissions at the after-treatment device inlet, specific NOx emissions at the after-treatment device outlet, and NOx conversion efficiency are calculated based on the accumulated work, the accumulated NOx flow rate at the after-treatment device inlet, and the accumulated NOx flow rate at the after-treatment device outlet;

[0018] The target NOx emission ratio at the inlet of the after-treatment device is determined based on the NOx conversion efficiency.

[0019] According to the above solution, the method for determining the combustion mode coefficient request value and the combustion mode coefficient actual value based on the NOx target specific emission ratio and the NOx specific emission ratio at the after-treatment device inlet includes:

[0020] Comparing the target specific NOx emissions at the inlet of the after-treatment device with the specific NOx emissions at the outlet of the after-treatment device under different combustion modes in the pre-calibrated results under the current operating conditions, and setting the combustion mode coefficient request value according to the comparison result;

[0021] Comparing the NOx emission ratio at the inlet of the aftertreatment device with the NOx emission ratio at the outlet of the aftertreatment device under different combustion modes in the pre-calibrated results under the current operating conditions, and setting the actual value of the combustion mode coefficient based on the comparison result;

[0022] The pre-calibration results include the ignition angle, air-fuel ratio, injection advance angle, fuel rail pressure, NOx emission ratio at the outlet of the after-treatment device, and fuel consumption emission ratio under each operating condition and combustion mode.

[0023] According to the above solution, the method for determining the final output combustion mode setting value based on the combustion mode coefficient request value and the combustion mode coefficient actual value includes:

[0024] determining a combustion mode coefficient deviation according to a combustion mode coefficient request value and an actual value of the combustion mode coefficient;

[0025] Determining a proportional term based on a combustion mode coefficient deviation;

[0026] determining an integral term based on a combustion mode coefficient deviation;

[0027] Determine the final output combustion mode setting value according to the combustion mode coefficient request value, proportional term, and integral term;

[0028] The final output combustion mode setting value S is limited.

[0029] According to the above scheme, the method for determining the combustion mode interpolation, air-fuel ratio interpolation, fuel rail pressure interpolation, injection angle interpolation, and ignition angle interpolation according to the final output combustion mode setting value includes:

[0030] determining a combustion mode interpolation value according to a final output combustion mode setting value;

[0031] determining an air-fuel ratio interpolation value based on the combustion mode interpolation;

[0032] determining a fuel rail pressure interpolation value based on the combustion mode interpolation;

[0033] An ignition angle interpolation is determined based on the combustion mode interpolation.

[0034] According to the above scheme, there are four combustion modes, including: a combustion mode with an air-fuel ratio of the minimum air-fuel ratio for stable combustion, a combustion mode with an air-fuel ratio equal to 1, a combustion mode with the lowest fuel consumption, and a combustion mode with an air-fuel ratio of the maximum air-fuel ratio for stable lean combustion.

[0035] According to the above solution, the method for limiting the final output combustion mode setting value is: limiting the final output combustion mode setting value to be no less than 1 and no more than 4.

[0036] The present invention also provides a computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of any of the above exhaust gas treatment control methods when executing the computer program.

[0037] The present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the exhaust gas treatment control method described above.

[0038] The present invention also provides an automobile, which adopts the exhaust gas treatment control method described above.

[0039] The beneficial effects of the present invention are as follows: the method detects the NOx emission concentration before and after post-treatment, thereby obtaining a final output combustion mode setting value, then compares the final output combustion mode setting value with the combustion mode number of a preset combustion mode, and performs interpolation processing based on the comparison result and the air-fuel ratio, fuel rail pressure, injection angle, and ignition angle in each combustion mode to obtain the final air-fuel ratio interpolation, fuel rail pressure interpolation, injection angle interpolation, and ignition angle interpolation used to control the engine, thereby solving the emission risk caused by lean combustion. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is a flow chart of the exhaust gas treatment control method according to the first embodiment of the present invention;

[0041] Figure 2 This is a schematic diagram of the post-processing device configuration according to the first embodiment of the present invention. DETAILED DESCRIPTION

[0042] To make the purpose, technical solutions, and advantages of the embodiments of the present disclosure more clear, the technical solutions of the embodiments of the present disclosure will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0043] Example 1:

[0044] See also Figure 1 This embodiment discloses a method for controlling exhaust gas treatment. The method is applicable to the following post-processing device configuration: Figure 2 , the method comprises the following steps:

[0045] S1. Detect and obtain a NOx emission concentration before and after post-treatment, and determine a target NOx emission ratio at an inlet of the post-treatment device and a NOx emission ratio at an inlet of the post-treatment device based on the NOx emission concentration before and after post-treatment.

[0046] S1 specifically includes the following steps:

[0047] S101, read the NOx emission concentration before post-processing NOx_raw through the post-processing sensor in , NOx emission concentration after post-treatment NOx_raw out ;

[0048] S102, NOx emission concentration before post-treatment NOx_raw in , NOx emission concentration after post-treatment NOx_raw out Filter them separately to obtain the filtered value of NOx emission concentration before post-treatment in , NOx emission concentration filtered value after post-treatment NOx out ;

[0049] It should be understood that since NOx emissions change dramatically in a transient state, smoothing processing is required.

[0050] S103, based on the NOx emission concentration filter value before post-processing NOx in , NOx emission concentration filtered value after post-treatment NOx out , determine the NOx flow rate at the inlet of the post-treatment device in_flow , NOx flow rate at the outlet of post-treatment device out_flow ;

[0051] NOx in_flow =NOx in / 10 7 *Exh / Mol exh *Mol nox *10 3 / P pwr

[0052] NOx out_flow =NOx out / 10 7 *Exh / Mol exh *Mol nox *10 3 / Ppwr

[0053] In the above formula, NOx in_flow 、NOx out_flow The unit is g / h, NOx in 、NOx out The unit is ppm, Exh is the exhaust gas flow rate, the unit is kg / h, Mol exh is the number of exhaust gas molecules, Mol nox is the number of NOx moles, P pwr is the engine power in kW;

[0054] Exh=Air+Fuel

[0055] P pwr =Speed*Torque / 9550

[0056] In the above formula, Air is the intake air flow (obtained by a sensor or other EMS modules using the general speed density method); Fuel is the fuel flow (obtained by other EMS modules based on the actual injection time of the injector), Speed ​​is the engine speed in r / min, and Torque is the engine output torque in Nm.

[0057] S104, according to the engine power P pwr , determine the cumulative power Pwr of the engine during the running time T sum ;

[0058]

[0059] In the above formula, T sample is a fixed operating cycle, which is 10ms in this embodiment;

[0060] S105, according to the NOx flow rate NOx at the inlet of the post-treatment device in_flow , NOx flow rate at the outlet of post-treatment device out_flow , determine the NOx cumulative flow rate NOxIN at the inlet of the post-treatment device sum , NOx cumulative flow rate at the outlet of the post-treatment device NOxOut sum ;

[0061]

[0062] S106, when the accumulated power or running time reaches their respective limits, the accumulated power Pwr sum , NOx cumulative flow rate at the inlet of the post-treatment device NOxIN sum , NOx cumulative flow rate at the outlet of the post-treatment device NOxOut sum , calculate the NOx ratio of the after-treatment device inlet to the emission NOxINfinal , NOx emission ratio at the outlet of post-treatment device NOxOut final 、NOx conversion efficiency Eff nox ;

[0063] When any of the following conditions is met, the flag is activated. full , set Flag full =1;

[0064] 1) Pwr sum >=Pwr lim ;

[0065] 2) T>=T max

[0066] Among them, Pwr lim is the pre-calibrated cumulative power limit value, T max is the pre-calibrated operating time limit (set to 30s in this embodiment)

[0067] When Flag full =1, the following calculation is performed:

[0068] NOxIN final =NOxIN sum / Pwr sum

[0069] NOxOut final =NOxOut sum / Pwr sum

[0070] Eff nox =(NOxIn final- NOxOut final ) / NOxIn final

[0071] At the same time, set to reset, set T = 0; Pwr sum =0; Pwr = 0; NOxIN sum =0; NOxOut sum =0;Flag full =0, repeat the above accumulation;

[0072] S107, according to NOx conversion efficiency Eff nox Determine the NOx target ratio at the inlet of the after-treatment device and emit NOx target ;

[0073] NOx target =NOx tlim *(1-Eff nox )

[0074] In the above formula, NOx tlim is the preset minimum NOx specific emission limit;

[0075] According to the real-time emission efficiency, the closed loop requests the original emission value;

[0076] It should be understood that when lean combustion is prolonged, the SCR outlet emissions are high, which will lead to Eff nox Lower efficiency, lower NOx required.

[0077] S2. Determine a combustion mode coefficient request value and an actual combustion mode coefficient value based on the target NOx emission ratio at the after-treatment device inlet and the NOx emission ratio at the after-treatment device inlet.

[0078] In S2, a combustion mode coefficient request value and an actual combustion mode coefficient value are determined based on pre-calibration results. The pre-calibration results include ignition angle, injection advance angle, fuel rail pressure, NOx emission ratio at the outlet of the after-treatment device, and fuel consumption emission ratio under four different combustion modes of each operating condition.

[0079] The combustion mode number corresponding to different combustion modes is defined as P, P = 1, 2, 3, 4;

[0080] P = 1 indicates a combustion mode in which the air-fuel ratio is the minimum air-fuel ratio for stable combustion;

[0081] P = 2 indicates a combustion mode with an air-fuel ratio equal to 1 (i.e., stoichiometric combustion);

[0082] P=3 indicates the combustion mode with the lowest fuel consumption;

[0083] P=4 indicates a combustion mode in which the air-fuel ratio is the maximum air-fuel ratio that can stabilize lean combustion;

[0084] The pre-calibration result under a certain operating condition is expressed as:

[0085]

[0086] Among them, the operating conditions are determined according to the engine speed and intake volume. During the calibration process, each operating condition is obtained by evenly taking points within the engine speed range and intake volume range to obtain multiple engine speed and intake volume ranges, and combined to form multiple operating conditions.

[0087] S2 specifically includes the following steps:

[0088] S201, the post-treatment device inlet NOx target ratio emission NOx target Compare the NOx emission ratio of the after-treatment device outlet under different combustion modes with the pre-calibrated results under the current operating conditions, and set the combustion mode coefficient request value P according to the comparison results. target ;

[0089] 1) If NOx target <NOx p1 , at this time it is the richest combustion, so the combustion mode coefficient request value P is set target =1;

[0090] 2) If NOx p1 <=NOx target <NOx p2 , then the first interpolation coefficient k1=(NOx target -NOx p1 ) / (NOx p2 -NOx p1 );

[0091] If the BSFC p1 >BSFC p2 , then the current minimum fuel consumption is k1*BSFC p2 +(1-k1)*BSFC p1 , so that P target =1+k1; otherwise, the current minimum fuel consumption is BSFC p1 , so that P target =1;

[0092] 3) If NOx p2 <=NOx target <NOx p3 , then the second interpolation setting coefficient k2=(NOx target -NOx p2 ) / (NOx p3 -NOx p2 );

[0093] If the BSFC p2 >BSFC p3 , then the current minimum fuel consumption is k2*BSFC p3 +(1-k2)*BSFC p2 , so that P target =2+k2; otherwise the current minimum fuel consumption is BSFC p2 , so that P target =2;

[0094] 4) If NOx p3 <=NOx target <NOx p4 , then the third setting coefficient k3=(NOx target -NOx p3 ) / (NOx p4 -NOx p3 )

[0095] If the BSFC p3 >BSFC p4 ; then the current minimum fuel consumption is k 3* BSFC p4 +(1-k3)*BSFC p3 , so that P target =3+k3, otherwise the current minimum fuel consumption is BSFC p3 , so that P target =3;

[0096] 5) If NOx target >NOx p4 , then set P target =4; this is the leanest combustion;

[0097] It is understandable that, since the NOx target is selected based on the minimum fuel consumption, under normal circumstances, NOx p3 is the lowest, so P target It will approach the direction of 3, that is, the direction of optimal fuel consumption. When lean combustion leads to a higher NOx value, the system conversion efficiency is low, P target A lower coefficient will be requested to enter the rich combustion area.

[0098] S202, reduce the NOx at the inlet of the post-treatment device to the emission NOxIN final Compare the NOx emission ratio of the after-treatment device outlet under different combustion modes in the pre-calibrated results under the current operating conditions, and set the actual value of the combustion mode coefficient P according to the comparison results. real ;

[0099] 1) If NOxIn final <NOx p1 , then set P real =1;

[0100] 2) If NOx p1 <=NOxIn final <NOx p2 , then set the coefficient k2 = (NOxIn final -NOx p1 ) / (NOx p2 -NOx p1 ), set P real =1+k2;

[0101] 3) If NOx p2 <=NOx target <NOx p3 , then set the coefficient k2 = (NOxIn final -NOx p2 ) / (NOx p3 -NOx p2), set P real =2+k2;

[0102] 4) If NOx p3 <=NOxIn final <NOx p4 , then set the coefficient k3 = (NOxIn final -NOx p3 ) / (NOx p4 -NOx p3 ), set P real =3+k2;

[0103] 5) If NOxIn final >=NOx p4 , then set P real =4.

[0104] S3. Determine a final output combustion mode setting value based on the combustion mode coefficient request value and the combustion mode coefficient actual value;

[0105] S3 specifically includes the following steps:

[0106] S301, according to the combustion mode coefficient request value P target , Actual value of combustion mode coefficient P real Determine the combustion mode coefficient deviation P err ;

[0107] S302, according to the combustion mode coefficient deviation P err Determine the proportional term P gain ;

[0108] P gain =Kp*P err

[0109] In the above formula, Kp is the proportional coefficient, which is determined by looking up the table according to the operating conditions;

[0110] S303, according to the combustion mode coefficient deviation P err Determine the integral term I gain ;

[0111]

[0112] In the above formula, Ki is the integral coefficient, which is calculated based on the NOx ratio of the current post-treatment device inlet to the emission NOxIN final The rate of change is determined by looking up the table;

[0113] S303, according to the combustion mode coefficient request value P target , proportional term P gain 、Integral term I gain , determine the final output combustion mode setting value S;

[0114] S = P target + P gain + I gain

[0115] S304. Limit the final output combustion mode setting value S;

[0116] Specifically, limit S to be not less than 1 and not greater than 4.

[0117] S4. Determine the combustion mode interpolation, air-fuel ratio interpolation, fuel rail pressure interpolation, injection angle interpolation, and ignition angle interpolation according to the final output combustion mode setting value;

[0118] S4 specifically includes the following steps:

[0119] S401. Determine the combustion mode interpolation S according to the final output combustion mode setting value S interp ;

[0120] 1) If S = 1, then set S high = S low = 1, S interp = 0;

[0121] 2) If 1 < S < 2, then set S low = 1, S high = 2, S interp = (S - S low ) / (S high - S low );

[0122] 3) If 2 <= S < 3, then set S low = 2, S high = 3, S interp = (S - S low ) / (S high - S low );

[0123] ​​​​​​​​​​​​​​​​​​​​​​​​​​​​​

[0126] S402, interpolate S according to the combustion mode interp Determine the air-fuel ratio interpolation Lambda interp ;

[0127] By looking up the pre-calibration results under the current operating conditions, we can obtain P=S low The corresponding air-fuel ratio is taken as Lambda low ;

[0128] By looking up the pre-calibration results under the current operating conditions, we can obtain P=S high The corresponding air-fuel ratio is used as Lambda high ;

[0129] Lambda interp =Lambda low +S interp *(Lambda high -Lambda low )

[0130] S403, interpolate S according to the combustion mode interp Determine the fuel rail pressure interpolation Rail interp ;

[0131] By looking up the pre-calibration results under the current operating conditions, we can obtain P=S low The corresponding fuel rail pressure is used as Rail low ;

[0132] By looking up the pre-calibration results under the current operating conditions, we can obtain P=S high The corresponding fuel rail pressure is used as Rail high ;

[0133] S404, interpolate S according to the combustion mode interp Determine the injection angle interpolation Injection interp ;

[0134] By looking up the pre-calibration results under the current operating conditions, we can obtain P=S low The corresponding injection angle is used as Injection low ;

[0135] By looking up the pre-calibration results under the current operating conditions, we can obtain P=S high The corresponding injection angle is used as Injection high ;

[0136] Injectioninterp =Injection low +S interp *(Injection hig -Injection low )

[0137] S405, interpolate S according to the combustion mode interp Determine the ignition angle interpolation Sprk interp ;

[0138] By looking up the pre-calibration results under the current operating conditions, we can obtain P=S low The corresponding ignition angle is taken as Sprk low ;

[0139] By looking up the pre-calibration results under the current operating conditions, we can obtain P=S high The corresponding ignition angle is taken as Sprk high ;

[0140] Sprk interp =Sprk low +S interp *(Sprk hig -Sprk low )

[0141] The above air-fuel ratio interpolation Lambda interp , fuel rail pressure interpolation Rail interp , Injection angle interpolation interp , ignition angle interpolation Sprk interp Used to control engine combustion.

[0142] This solution captures multiple air-fuel ratio combustion modes. Based on real-time emissions feedback from the aftertreatment system and the target minimum fuel consumption, it requests combustion mode coefficients. This closed-loop process is repeated, and the combustion parameters are interpolated to output real-time combustion parameters. This dual closed-loop approach not only optimizes engine combustion efficiency and reduces fuel consumption through lean burn, but also mitigates the emissions risks associated with lean burn.

[0143] Example 2:

[0144] An embodiment of the present invention provides a computer device, which may be a smartphone, tablet computer, laptop computer, desktop computer, rack server, blade server, tower server, or cabinet server (including a standalone server or a server cluster consisting of multiple servers), capable of executing programs. The computer device of this embodiment includes at least, but is not limited to, a memory and a processor that are communicatively connected via a system bus.

[0145] In this embodiment, the memory (i.e., readable storage medium) includes flash memory, hard disk, multimedia card, card-type memory (e.g., SD or DX memory, etc.), random access memory (RAM), static random access memory (SRAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), and programmable read-only memory (PROM). The memory can also be an external storage device of the computer device, such as a plug-in hard disk equipped with the computer device, a smart memory card (SmartMedia Card, SMC), a secure digital (Secure Digital, SD) card, a flash card, etc. Of course, the memory can also include both the internal storage unit of the computer device and its external storage device. In this embodiment, the memory is generally used to store the operating system and various application software installed in the computer device, such as the program code of the exhaust gas treatment control method in Example 1. In addition, the memory can also be used to temporarily store various types of data that have been output or are about to be output.

[0146] In some embodiments, the processor may be a central processing unit (CPU), a controller, a microcontroller, a microprocessor, or other data processing chip. The processor is generally used to control the overall operation of a computer device. In this embodiment, the processor is used to execute program code stored in a memory or process data, such as executing the program code of the exhaust gas treatment control method in Example 1 to implement the exhaust gas treatment control method in Example 1.

[0147] Example 3:

[0148] This embodiment provides a computer-readable storage medium, such as a flash memory, a hard disk, a multimedia card, a card-type memory (e.g., an SD or DX memory), a random access memory (RAM), a static random access memory (SRAM), a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), a programmable read-only memory (PROM), a magnetic memory, a disk, an optical disk, a server, an App store, etc., on which a computer program is stored, and when the program is executed by a processor, a corresponding function is implemented. The computer-readable storage medium of this embodiment is used to store the program code of the exhaust gas treatment control method, and when executed by the processor, the exhaust gas treatment control method of Example 1 is implemented.

[0149] Example 4:

[0150] This embodiment provides a car that implements the exhaust gas treatment control method in the first embodiment.

[0151] It should be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0152] It should be pointed out that, according to the needs of implementation, the various steps / components described in this application can be split into more steps / components, or two or more steps / components or partial operations of steps / components can be combined into new steps / components to achieve the purpose of the present invention.

[0153] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention description and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A tail gas treatment control method, characterized in that: include: Detecting and obtaining the NOx emission concentration before and after post-treatment, and determining the NOx target ratio emission at the inlet of the post-treatment device and the NOx ratio emission at the inlet of the post-treatment device based on the NOx emission concentration before and after post-treatment; Determining a combustion mode coefficient request value and an actual combustion mode coefficient value based on a target NOx emission ratio at an after-treatment device inlet and a NOx emission ratio at an after-treatment device inlet; Determine the final output combustion mode setting value according to the combustion mode coefficient request value and the combustion mode coefficient actual value; Determining combustion mode interpolation, air-fuel ratio interpolation, fuel rail pressure interpolation, injection angle interpolation, and ignition angle interpolation based on the final output combustion mode setting value; the air-fuel ratio interpolation, fuel rail pressure interpolation, injection angle interpolation, and ignition angle interpolation are used to control engine combustion; The method for determining the target NOx emission ratio at the inlet of the post-treatment device and the NOx emission ratio at the inlet of the post-treatment device according to the NOx emission concentration before post-treatment and the NOx emission concentration after post-treatment includes: The NOx emission concentration before and after post-treatment is read by the post-treatment sensor; Filtering the NOx emission concentration before post-treatment and the NOx emission concentration after post-treatment respectively to obtain a filtered value of the NOx emission concentration before post-treatment and a filtered value of the NOx emission concentration after post-treatment; Determine the NOx flow rate at the inlet of the post-treatment device and the NOx flow rate at the outlet of the post-treatment device according to the filtered value of the NOx emission concentration before post-treatment and the filtered value of the NOx emission concentration after post-treatment; Based on the engine power, determine the cumulative work of the engine during the running time; Determine the accumulated NOx flow rate at the inlet of the post-treatment device and the accumulated NOx flow rate at the outlet of the post-treatment device according to the NOx flow rate at the inlet of the post-treatment device and the NOx flow rate at the outlet of the post-treatment device; When the accumulated work or operating time reaches their respective limits, the specific NOx emissions at the after-treatment device inlet, specific NOx emissions at the after-treatment device outlet, and NOx conversion efficiency are calculated based on the accumulated work, the accumulated NOx flow rate at the after-treatment device inlet, and the accumulated NOx flow rate at the after-treatment device outlet; The target NOx emission ratio at the inlet of the after-treatment device is determined based on the NOx conversion efficiency.

2. The exhaust gas treatment control method according to claim 1, characterized in that: The method for determining the combustion mode coefficient request value and the combustion mode coefficient actual value based on the NOx target emission ratio and the NOx emission ratio at the after-treatment device inlet includes: Comparing the target specific NOx emissions at the inlet of the after-treatment device with the specific NOx emissions at the outlet of the after-treatment device under different combustion modes in the pre-calibrated results under the current operating conditions, and setting the combustion mode coefficient request value according to the comparison result; Comparing the NOx emission ratio at the inlet of the aftertreatment device with the NOx emission ratio at the outlet of the aftertreatment device under different combustion modes in the pre-calibrated results under the current operating conditions, and setting the actual value of the combustion mode coefficient based on the comparison result; The pre-calibration results include the ignition angle, air-fuel ratio, injection advance angle, fuel rail pressure, NOx emission ratio at the outlet of the after-treatment device, and fuel consumption emission ratio under each operating condition and combustion mode.

3. The exhaust gas treatment control method according to claim 2, characterized in that: The method for determining the final output combustion mode setting value according to the combustion mode coefficient request value and the combustion mode coefficient actual value includes: determining a combustion mode coefficient deviation according to a combustion mode coefficient request value and an actual value of the combustion mode coefficient; Determining a proportional term based on a combustion mode coefficient deviation; determining an integral term based on a combustion mode coefficient deviation; Determine the final output combustion mode setting value according to the combustion mode coefficient request value, proportional term, and integral term; The final output combustion mode setting value S is limited.

4. The exhaust gas treatment control method according to claim 1, characterized in that: The method for determining the combustion mode interpolation, air-fuel ratio interpolation, fuel rail pressure interpolation, injection angle interpolation, and ignition angle interpolation according to the final output combustion mode setting value includes: determining a combustion mode interpolation value according to a final output combustion mode setting value; determining an air-fuel ratio interpolation value based on the combustion mode interpolation; determining a fuel rail pressure interpolation value based on the combustion mode interpolation; The ignition angle interpolation is determined based on the combustion mode interpolation.

5. The exhaust gas treatment control method according to claim 3, characterized in that: There are four combustion modes, including: a combustion mode with an air-fuel ratio of the minimum air-fuel ratio for stable combustion, a combustion mode with an air-fuel ratio equal to 1, a combustion mode with the lowest fuel consumption, and a combustion mode with an air-fuel ratio of the maximum air-fuel ratio for stable lean combustion.

6. The exhaust gas treatment control method according to claim 5, characterized in that: The method for limiting the final output combustion mode setting value is: limiting the final output combustion mode setting value to be no less than 1 and no more than 4.

7. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the steps of the exhaust gas treatment control method according to any one of claims 1 to 6 are implemented.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the exhaust gas treatment control method according to any one of claims 1 to 6 are implemented.

9. An automobile, characterized in that: The automobile adopts the exhaust gas treatment control method described in any one of claims 1 to 6.

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