Optimization control method for pressurization closed-loop enabling

Abstract

The invention discloses an optimization control method for pressurization closed-loop enabling. The optimization control method comprises the steps that whether the pressure in a compressor of an engine supercharger assembly meets the minimum pressure condition or not is judged; judging whether the engine speed meets the engine speed condition or not; whether a pressure release valve of the engine supercharger assembly is not opened or not is judged; if all the judgments are yes, pressurization closed-loop enabling is allowed, and pressurization closed-loop control is carried out after pressurization closed-loop enabling; otherwise, the pressurization closed-loop enabling is not carried out. According to the method, the pressurization closed-loop enabling condition is optimized, the pressure control stability when pressurization enters a closed loop is improved, the pressurization responsiveness and the EGR system responsiveness are improved, pressurization closed-loop control is optimized, in other words, the engine rotating speed condition and the minimum pressure condition are optimized under different EGR working conditions, and therefore the engine performance is improved. And dynamic learning optimization is carried out under the minimum pressure condition, learning parameters are continuously updated in the subsequent control process, and the pressurization control stability is further improved.

Description

Technical Field

[0001] The invention belongs to the technical field of engine control, and in particular relates to an optimization control method for boost closed-loop enabling. Background Art

[0002] In order to respond to the engine intake boost and engine torque increase request, the boost system is controlled to achieve more exhaust energy to achieve boost. The boost control determines the engine's power and economy, etc. Boost closed-loop control refers to actively controlling the action of the boost actuator to achieve the tracking of the actual boost pressure and the target boost pressure.

[0003] Patent CN201910988050.8 "Exhaust Gas Turbine Engine Boost Closed-Loop Adaptive System and Control Method" mentions the judgment of boost closed-loop enabling conditions, but its judgment of pressure control stability when the boost enters the closed loop and the boost responsiveness and EGR system responsiveness are defective, and the boost closed-loop control method needs to be optimized. Summary of the invention

[0004] The purpose of the present invention is to provide an optimized control method for boost closed-loop enabling, which improves the pressure control stability when the boost enters the closed-loop and improves the boost responsiveness and EGR system responsiveness, thereby optimizing the boost closed-loop control.

[0005] In order to solve the above technical problems, the technical solution of the present invention is: an optimization control method for boost closed-loop enabling, comprising:

[0006] Determine whether the pressure inside the compressor of the engine supercharger assembly meets the minimum pressure condition;

[0007] Determine whether the engine speed meets the engine speed condition;

[0008] Determine whether the pressure relief valve of the engine supercharger assembly is not open;

[0009] When the above judgments are all yes, boost closed loop enabling is allowed, and boost closed loop control is performed after boost closed loop enabling; otherwise, boost closed loop enabling is not performed.

[0010] The minimum pressure conditions are as follows:

[0011] Set the minimum pressure condition flag bit b BoostEnaRaw , defines the minimum pressure characteristic value b collected in the compressor of the engine supercharger assembly BoostEna Greater than or equal to the minimum pressure condition flag bit b BoostEnaRaw The minimum pressure condition flag is b at this time BoostEnaRaw When it is 1, it is judged that the minimum pressure condition is met; the minimum pressure condition flag bit b BoostEnaRaw The value of is 0 or 1.

[0012] Minimum pressure characteristic value b BoostEna The calculation method is:

[0013]

[0014] Among them, k1 is the weighting coefficient, r EGRAct is the actual EGR rate, r EGRDesrd is the target EGR rate, n is the engine speed; r Adapt It is the self-learning correction coefficient of the self-learning minimum pressure characteristic value. Its default value is 0 and it can be continuously updated through self-learning, and it is saved after the vehicle is powered off.

[0015] The engine speed conditions are as follows:

[0016] A first speed preset value A is set, and it is defined that when the engine speed is greater than the first speed preset value A, the engine speed condition is judged to be met; wherein, the first speed preset value A changes according to the actual EGR rate, when the actual EGR rate is 0, the first speed preset value A is equal to the third speed preset value D; when the actual EGR rate is not 0, the first speed preset value A is greater than or equal to the third speed preset value D.

[0017] When the actual EGR rate is not 0, the specific value of the first speed preset value A is expressed as:

[0018] A preset opening value greater than 0 is set. When the EGR valve position opening is greater than the preset opening value, the first speed preset value A is expressed as:

[0019] A=B×f1(rho,r EGRAct )

[0020] Among them, f1(rho,r EGRAct ) is a constant greater than or equal to 1, and its value varies with the actual EGR rate r EGRAct It increases with the increase of , and decreases with the increase of the cylinder fresh air intake density rho;

[0021] When the EGR valve position opening is 0, the first speed preset value A is expressed as:

[0022] A=B×f2(rho,r EGRAct )

[0023] Among them, f2(rho,r EGRAct ) is a constant less than or equal to 1, and its value varies with the actual EGR rate r EGRAct It decreases with the increase of , and decreases with the increase of the cylinder fresh air intake density rho.

[0024] Self-learning minimum pressure characteristic value Self-learning correction coefficient r Adapt The self-learning update conditions are:

[0025] (1) The engine speed fluctuation is within the preset speed fluctuation range;

[0026] (2) The fresh air mass flow rate fluctuation of the engine entering the cylinder is within the preset flow rate fluctuation range;

[0027] (3) The boost control is in the closed-loop enabled state;

[0028] (4) The deviation between the target EGR rate and the actual EGR rate does not exceed the preset deviation value;

[0029] (5) The target EGR rate fluctuation range does not exceed the preset EGR rate fluctuation range;

[0030] (6) No malfunction occurs to any engine component;

[0031] When all the above conditions are met, and the following conditions are met: the above condition state is maintained for a time longer than the first preset time t1, and the boost control is in the closed-loop enabled state for a time longer than the preset time t2, where t2 is greater than t1;

[0032] The average value of the engine speed from t1 to t2 when all reading conditions are met, the average value of the fresh air mass flow entering the cylinder, the average value of the ratio of the actual EGR rate to the target EGR rate, and the average value of the absolute value of the difference between the final target boost pressure and the actual boost pressure p BoostErrAvg , the absolute average value of the difference between the final target intake pressure and the actual intake pressure p AftErrAvg According to the above values, self-learn the minimum pressure characteristic value self-learning correction coefficient r Adapt Self-learning update.

[0033] Self-learning minimum pressure characteristic value Self-learning correction coefficient r Adapt The update method is expressed as:

[0034] 1) When the absolute average value of the difference between the final target boost pressure and the actual boost pressure is p BoostErrAvg ≤p1, and CNT1>m1, then update r under the corresponding working condition Adapt =r Adapt (z) -0.002, and CNT1 is cleared to 0; where p1 is the first pressure difference threshold, and m1 is the cumulative number threshold;

[0035] 2) p BoostErrAvg >p2,p AftErrAvg ≤p1, and CNT1>m1, then update r under the corresponding working condition Adapt =r Adapt (z)+0.0001; and CNT1 is cleared to 0; wherein p2 is the second pressure difference threshold, and p2>p1;

[0036] 3) p BoostErrAvg >p2,p AftErrAvg >p2, and CNT1>m1, then update r under the corresponding working condition Adapt =r Adapt (z)+0.000012; and clear CNT1 to 0;

[0037] Among them, CNT1 will be reset every time the vehicle is powered off, r Adapt (z) is the self-learning correction coefficient of the self-learning minimum pressure characteristic value learned last time;

[0038] 5) r under other working conditions Adapt Not updated.

[0039] The purpose of the above self-learning is to take into account that the EGR system pipeline is long and complete, and there are many parts. As the engine life cycle progresses, the boost closed-loop enabling conditions may need to be updated and adjusted in order to control the accuracy of the boost pressure. Learning is based on this.

[0040] The value range of the third speed preset value D is 400-1000 rpm.

[0041] A computer device is also provided, 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 control methods described above when executing the computer program.

[0042] A computer-readable storage medium is also provided, on which a computer program is stored, and when the computer program is executed by a processor, the steps of any of the control methods described above are implemented.

[0043] Compared with the prior art, the present invention has the following beneficial effects:

[0044] The present invention optimizes the boost closed-loop control by optimizing the boost closed-loop enabling conditions, improving the pressure control stability when the boost enters the closed-loop and improving the boost responsiveness and the EGR system responsiveness. That is, the engine speed conditions and the minimum pressure conditions are optimized under different EGR conditions, the minimum pressure conditions are dynamically learned and optimized, and the learning parameters are continuously updated in the subsequent control process to further improve the boost control stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 It is a schematic diagram of a flow chart of an embodiment of the present invention;

[0046] Figure 2 Schematic diagram of the architecture of the low-pressure EGR system in an embodiment of the present invention. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0048] The technical solution of the present invention is:

[0049] An optimization control method for boost closed-loop enabling is applied to a system with a low-pressure EGR system and an exhaust gas turbocharger system, wherein the system structure includes an air filter, a mixing valve, a supercharger compressor, a throttle, an engine, a supercharger turbine, a catalyst, a particulate matter trap, an EGR cooler, an EGR valve, an EGR temperature sensor, an EGR differential pressure sensor, a flow meter and a linear oxygen sensor.

[0050] The supercharger compressor compresses fresh air for supercharging; the supercharger turbine controls the working efficiency of the turbine by controlling the opening of the supercharger's exhaust bypass valve, thereby achieving different supercharging capabilities; the low-pressure EGR system has the following additional components compared to the non-low-pressure EGR system: EGR cooler, EGR temperature sensor, EGR valve, EGR pressure difference sensor, mixing valve, flow meter and oxygen sensor; the flow meter is installed between the air filter and the mixing valve to detect the fresh air flow entering the engine, which is an alternative (the alternative means that whether to install it depends on the model, and it is optional. If not selected, the estimation method is used to obtain the corresponding information); mixing valve, used to adjust the pressure of the EGR valve outlet, increase the pressure difference at both ends of the EGR valve, and increase the EGR rate; oxygen sensor, optional, installed between the compressor and the throttle, close to the throttle, used to detect the flow of mixed gas entering the cylinder; EGR cooler, used to cool the exhaust gas, which is convenient for increasing the exhaust gas flow and reducing the exhaust gas temperature; EGR valve, throttling function, controls the exhaust gas flow entering the cylinder; EGR temperature sensor, used to detect the exhaust gas temperature entering the EGR valve; EGR pressure difference sensor, used to detect the pressure of the EGR inlet and outlet. The low-pressure EGR system architecture is as follows Figure 2 shown.

[0051] Embodiment 1:

[0052] An optimization control method for boost closed loop enabling, such as Figure 1 As shown, including:

[0053] S1. Determine whether the pressure inside the compressor of the engine supercharger assembly meets the minimum pressure condition;

[0054] S2, determining whether the engine speed meets the engine speed condition;

[0055] S3, determining whether the pressure relief valve of the engine supercharger assembly is not opened;

[0056] S4. When the above judgments are all yes, boost closed loop enabling is allowed, and boost closed loop control is performed after boost closed loop enabling; otherwise, boost closed loop enabling is not performed.

[0057] Patent CN201910988050.8 "Exhaust gas turbine engine boost closed loop adaptive system and control method" mentions the boost closed loop enabling condition judgment, but in order to improve the pressure control stability when the boost enters the closed loop and improve the boost responsiveness and EGR system responsiveness, the boost closed loop control is optimized. That is, determine the boost closed loop enabling condition judgment:

[0058] Minimum pressure condition: Patent CN201910988050.8 "Exhaust gas turbine engine boost closed loop adaptive system and control method" mentions the minimum pressure condition flag, which means that the boost closed loop is allowed to be enabled only when the minimum pressure condition flag is 1, otherwise it is not allowed to enter the boost closed loop. That is, the minimum pressure condition flag is 1, which is a necessary but not sufficient condition for boost to enter the closed loop, and the flag is adjusted to only 0 and 1.

[0059] In the embodiment of the present invention, the minimum pressure condition is specifically:

[0060] Set the minimum pressure condition flag bit b BoostEnaRaw , defines the minimum pressure characteristic value b collected in the compressor of the engine supercharger assembly BoostEna Greater than or equal to the minimum pressure condition flag bit b BoostEnaRaw The minimum pressure condition flag is b at this time BoostEnaRaw When it is 1, it is judged that the minimum pressure condition is met; the minimum pressure condition flag bit b BoostEnaRaw The value of is 0 or 1.

[0061] The calculation method of the minimum pressure characteristic value is:

[0062]

[0063] Wherein, k1 is the weighting coefficient, which is 0.1 in this embodiment, and r EGRAct is the actual EGR rate, r EGRDesrd is the target EGR rate, n is the engine speed; r Adapt It is the self-learning correction coefficient of the self-learning minimum pressure characteristic value. Its default value is 0 and it can be continuously updated through self-learning, and it is saved after the vehicle is powered off. The larger the value, the greater the deviation between the actual EGR rate and the target EGR rate. The larger the value, the faster the boost closed loop is enabled, so as to ensure that when the EGR rate demand increases, the boost outlet pressure is stable when the boost inlet pressure decreases, ensuring the stability of the power. The calibration method is to set different engine speeds at different In this case, within a preset time (0.5s in this embodiment) after the boost closed loop is enabled, the actual boost pressure can be close to the target boost pressure. In this embodiment, the boost pressure closeness means that the difference between the actual boost pressure and the target boost pressure does not exceed ±2kPa. BoostEna If it is not less than 1, it indicates that the minimum pressure condition is met.

[0064] The engine speed conditions are as follows:

[0065] A first speed preset value A is set, and it is defined that when the engine speed is greater than the first speed preset value A, the engine speed condition is judged to be met; wherein, the first speed preset value A changes according to the actual EGR rate, when the actual EGR rate is 0, the first speed preset value A is equal to the third speed preset value D; when the actual EGR rate is not 0, the first speed preset value A is greater than or equal to the third speed preset value D.

[0066] When the actual EGR rate is not 0, the specific value of the first speed preset value A is expressed as:

[0067] A preset opening value greater than 0 is set (0.6% in this embodiment). When the EGR valve position opening (the opening is 0%, indicating that the gas on both sides of the EGR valve is blocked and does not flow; the larger the opening, the larger the effective flow area on both sides of the EGR valve) is greater than the preset opening value, the first speed preset value A is expressed as:

[0068] A=B×f1(rho,r EGRAct )

[0069] Among them, f1(rho,r EGRAct ) is a constant greater than or equal to 1, and its value varies with the actual EGR rate r EGRAct increases with the increase of the cylinder fresh air intake density rho, and decreases with the increase of the cylinder fresh air intake density rho; f1(rho,r EGRAct ) The calibration method is to conduct a large number of experiments on each engine with different fresh air intake density rho and different EGR rate r EGRAct Under this condition, a large number of tests were conducted to determine the lowest average engine speed n that satisfies the boost closed-loop control accuracy (the difference between the target boost pressure and the actual boost pressure is within ±2kPa, indicating that the boost closed-loop control accuracy is met). Avg , n Avg Dividing by B gives the fresh air intake density rho for each engine and each different EGR rate r EGRAct f1(rho,rEGRAct ).

[0070] When the EGR valve position opening is 0, the EGR system is about to be closed. Due to the delay of exhaust gas energy, the exhaust gas energy is relatively large, and the first speed preset value A is expressed as:

[0071] A=B×f2(rho,r EGRAct )

[0072] Among them, f2(rho,r EGRAct ) is a constant less than or equal to 1, and its value varies with the actual EGR rate r EGRAct f2(rho,r EGRAct ) The calibration method is to conduct a large number of experiments on each engine with different fresh air intake density rho and different EGR rate r EGRAct Under this condition, a large number of tests were conducted to determine the lowest average engine speed n that satisfies the boost closed-loop control accuracy (the difference between the target boost pressure and the actual boost pressure is within ±2kPa, indicating that the boost closed-loop control accuracy is met). Avg , n Avg Dividing by B gives the fresh air intake density rho for each engine and each different EGR rate r EGRAct f2(rho,r EGRAct ). Finally, A in this case is limited to not less than a preset value D, which is 700 rpm in this embodiment.

[0073] Self-learning minimum pressure characteristic value Self-learning correction coefficient r Adapt The self-learning update conditions are:

[0074] (1) The engine speed fluctuation is within a preset speed fluctuation range; in this embodiment, the preset range is ±15 rpm.

[0075] (2) The mass flow rate fluctuation of fresh air entering the cylinder of the engine is within a preset flow rate fluctuation range; 2. In this embodiment, ±0.1g / s is taken.

[0076] (3) The boost control is in the closed-loop enabled state;

[0077] (4) The deviation between the target EGR rate and the actual EGR rate does not exceed a preset deviation value; in this embodiment, it is set to ±0.1.

[0078] (5) The target EGR rate fluctuation range does not exceed the preset EGR rate fluctuation range; in this embodiment, it is set to ±0.1.

[0079] (6) No malfunction occurs to any engine component;

[0080] When all the above conditions are met, and the following conditions are met: the above condition state is maintained for more than the first preset time t1 (1s in this embodiment), and the boost control is in the closed-loop enabled state for no more than the preset time t2 (2s in this embodiment), where t2 is greater than t1;

[0081] The average value of the engine speed from t1 to t2 when all reading conditions are met, the average value of the fresh air mass flow entering the cylinder, the average value of the ratio of the actual EGR rate to the target EGR rate, and the average value of the absolute value of the difference between the final target boost pressure and the actual boost pressure p BoostErrAvg The absolute average value of the difference between the final target intake pressure (referring to the intake pressure target value at the throttle outlet) and the actual intake pressure p AftErrAvg According to the above values, self-learn the minimum pressure characteristic value self-learning correction coefficient r Adapt Self-learning update.

[0082] Self-learning minimum pressure characteristic value Self-learning correction coefficient r Adapt The update method is expressed as:

[0083] 1) When the absolute average value of the difference between the final target boost pressure and the actual boost pressure is p BoostErrAvg ≤p1, and CNT1>m1, then update r under the corresponding working condition Adapt =r Adapt (z)-0.002, and CNT1 is cleared to 0; mainly considering the high control accuracy of boost pressure, the boost closed-loop control can be entered later at this time to reduce the loss of exhaust energy caused by boost. In this embodiment, p1 is 2kPa and m1 is 20.

[0084] 2) p BoostErrAvg >p2,p AftErrAvg ≤p1, and CNT1>m1, then update r under the corresponding working condition Adapt =r Adapt (z) + 0.0001; and CNT1 is cleared to 0; wherein p2 in this embodiment is 3 kPa. This is mainly due to the poor control accuracy of the boost pressure (i.e. p BoostErrAvg Too large), at this time, you can enter the boost closed-loop control earlier to improve the boost pressure control accuracy. However, at this time, the intake pressure control accuracy is better and the adjustment coefficient will not be large

[0085] 3) p BoostErrAvg >p2,p AftErrAvg >p2, and CNT1>m1, then update r under the corresponding working condition Adapt =r Adapt (z) + 0.000012; and clear CNT1 to 0; mainly considering the poor control accuracy of boost pressure (i.e. p BoostErrAvgToo large), at this time, the boost closed-loop control can be entered earlier to improve the boost pressure control accuracy. However, the intake pressure control accuracy is poor at this time (i.e., p AftErrAvg If the value is too large), the adjustment factor will also increase.

[0086] Among them, CNT1 will be reset every time the vehicle is powered off, r Adapt (z) is the self-learning correction coefficient of the self-learning minimum pressure characteristic value learned last time;

[0087] 4) r under other working conditions Adapt Not updated.

[0088] The purpose of the above self-learning is to take into account that the EGR system pipeline is long and complete, and there are many parts. As the engine life cycle progresses, the boost closed-loop enabling conditions may need to be updated and adjusted in order to control the accuracy of the boost pressure. Learning is based on this.

[0089] Embodiment 2:

[0090] A computer device is also provided, 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 control methods described above when executing the computer program.

[0091] Embodiment 3:

[0092] A computer-readable storage medium is also provided, on which a computer program is stored, and when the computer program is executed by a processor, the steps of any of the control methods described above are implemented.

[0093] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0094] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0095] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0096] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0097] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An optimization control method for boost closed-loop enabling, characterized in that: include: Determine whether the pressure inside the compressor of the engine supercharger assembly meets the minimum pressure condition; Determine whether the engine speed meets the engine speed condition; Determine whether the pressure relief valve of the engine supercharger assembly is not open; When the above judgments are all yes, boost closed loop enabling is allowed, and boost closed loop control is performed after boost closed loop enabling; otherwise, boost closed loop enabling is not performed.

2. The optimization control method for boost closed-loop enabling according to claim 1, characterized in that: The minimum pressure conditions are as follows: Set the minimum pressure condition flag bit b BoostEnaRaw , defines the minimum pressure characteristic value b collected in the compressor of the engine supercharger assembly BoostEna Greater than or equal to the minimum pressure condition flag bit b BoostEnaRaw The minimum pressure condition flag is b at this time BoostEnaRaw When it is 1, it is judged that the minimum pressure condition is met; the minimum pressure condition flag bit b BoostEnaRaw The value of is 0 or 1.

3. The optimization control method for boost closed-loop enabling according to claim 2, characterized in that: Minimum pressure characteristic value b BoostEna The calculation method is: Among them, k1 is the weighting coefficient, r EGRAct is the actual EGR rate, r EGRDesrd is the target EGR rate, n is the engine speed; r Adapt It is the self-learning correction coefficient of the self-learning minimum pressure characteristic value. Its default value is 0 and it can be continuously updated through self-learning, and it is saved after the vehicle is powered off.

4. The optimization control method for boost closed-loop enabling according to claim 1, characterized in that: The engine speed conditions are as follows: A first speed preset value A is set, and it is defined that when the engine speed is greater than the first speed preset value A, the engine speed condition is judged to be met; wherein, the first speed preset value A changes according to the actual EGR rate, when the actual EGR rate is 0, the first speed preset value A is equal to the third speed preset value D; when the actual EGR rate is not 0, the first speed preset value A is greater than or equal to the third speed preset value D.

5. The optimization control method for boost closed-loop enabling according to claim 4, characterized in that: When the actual EGR rate is not 0, the specific value of the first speed preset value A is expressed as: A preset opening value greater than 0 is set. When the EGR valve position opening is greater than the preset opening value, the first speed preset value A is expressed as: A=B×f1(rho,r EGRAct ) Among them, f1(rho,r EGRAct ) is a constant greater than or equal to 1, and its value varies with the actual EGR rate r EGRAct It increases with the increase of , and decreases with the increase of the cylinder fresh air intake density rho; When the EGR valve position opening is 0, the first speed preset value A is expressed as: A=B×f2(rho,r EGRAct ) Among them, f2(rho,r EGRAct ) is a constant less than or equal to 1, and its value varies with the actual EGR rate r EGRAct It decreases with the increase of , and decreases with the increase of the cylinder fresh air intake density rho.

6. The optimization control method for boost closed-loop enabling according to claim 3, characterized in that: Self-learning minimum pressure characteristic value Self-learning correction coefficient r Adapt The self-learning update conditions are: (1) The engine speed fluctuation is within the preset speed fluctuation range; (2) The fresh air mass flow rate fluctuation of the engine entering the cylinder is within the preset flow rate fluctuation range; (3) The boost control is in the closed-loop enabled state; (4) The deviation between the target EGR rate and the actual EGR rate does not exceed the preset deviation value; (5) The target EGR rate fluctuation range does not exceed the preset EGR rate fluctuation range; (6) No failure occurs to any engine component; When all the above conditions are met, and the following conditions are met: the above condition state is maintained for a time longer than the first preset time t1, and the boost control is in the closed-loop enabled state for a time longer than the preset time t2, where t2 is greater than t1; The average value of the engine speed from t1 to t2 when all reading conditions are met, the average value of the fresh air mass flow entering the cylinder, the average value of the ratio of the actual EGR rate to the target EGR rate, and the average value of the absolute value of the difference between the final target boost pressure and the actual boost pressure. BoostErrAvg , the absolute average value of the difference between the final target intake pressure and the actual intake pressure p AftErrAvg According to the above values, self-learn the minimum pressure characteristic value self-learning correction coefficient r Adapt Self-learning update.

7. The optimization control method for boost closed-loop enabling according to claim 6, characterized in that: Self-learning minimum pressure characteristic value Self-learning correction coefficient r Adapt The update method is expressed as: 1) When the absolute average value of the difference between the final target boost pressure and the actual boost pressure is p BoostErrAvg ≤p1, and CNT1>m1, then update r under the corresponding working condition Adapt =r Adapt (z) -0.002, and CNT1 is cleared to 0; where p1 is the first pressure difference threshold, and m1 is the cumulative number threshold; 2) p BoostErrAvg >p2,p AftErrAvg ≤p1, and CNT1>m1, then update r under the corresponding working condition Adapt =r Adapt (z)+0.0001; and CNT1 is cleared to 0; wherein p2 is the second pressure difference threshold, and p2>p1; 3) p BoostErrAvg >p2,p AftErrAvg >p2, and CNT1>m1, then update r under the corresponding working condition Adapt =r Adapt (z)+0.000012; and clear CNT1 to 0; Among them, CNT1 will be reset every time the vehicle is powered off, r Adapt (z) is the self-learning correction coefficient of the self-learning minimum pressure characteristic value learned last time; 4) r under other working conditions Adapt Not updated.

8. The optimization control method for boost closed-loop enabling according to claim 5, characterized in that: The value range of the third speed preset value D is 400-1000 rpm.

9. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the control method according to any one of claims 1 to 8 are implemented.

10. 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 control method according to any one of claims 1 to 8 are implemented.

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