Method, system, apparatus, and medium for boost pressure control for an engine

Abstract

The application discloses a supercharging pressure control method for an engine, which comprises the following steps: obtaining a target supercharging pressure and an actual supercharging pressure, calculating a pressure deviation therebetween; collecting pressure deviations of a plurality of continuous sampling periods to form a sequence when a diagnosis activation condition is met, and calculating an estimated pressure deviation sequence by using a trend prediction model; determining that a low-supercharging-pressure fault occurs when the estimated sequence continuously presents a negative deviation and a proportion of the estimated sequence exceeding a dynamic threshold reaches a preset value. In response to the fault, selectively increasing the target supercharging pressure according to whether the engine is in a fuel cut mode, and performing closed-loop control on a supercharging actuator; meanwhile, safely exiting and restoring an original pressure when the diagnosis condition disappears, a throttle opening is too low, or a gas volume ratio exceeds a limit. The application can accurately identify the trend of insufficient supercharging pressure, adaptively compensate for the lack of pressure, and optimize torque response under the premise of ensuring the safety of the supercharger, so that the drivability and robustness of the engine are improved.

Description

Technical Field

[0001] This application relates to the field of engine control technology, specifically to a boost pressure control method, device and medium for engines, which is particularly suitable for fault diagnosis and adaptive after-treatment control of exhaust gas turbocharged engines when the boost pressure deviates from the target value. Background Technology

[0002] To respond to the engine's intake boost and torque increase requests, the turbocharging system utilizes exhaust energy to achieve boost. Boost control determines the engine's power and fuel economy. Therefore, it is necessary not only to quickly determine if there is a boost pressure malfunction, but also to perform appropriate post-malfunction handling to minimize the impact of the malfunction on engine performance.

[0003] Existing technology one uses the time integral rate of change to determine actuator responsiveness, but its diagnostic accuracy is low, it uses a universal fault detection threshold, and lacks diagnostic corrections for different operating conditions. Existing technology two requires performing diagnostics by compressing air through the electric supercharger while the vehicle is in the ignition-off state, adding extra costs. Therefore, there is an urgent need for a method and system that can accurately diagnose abnormal boost pressure and adaptively perform after-processing control to ensure engine torque accuracy and drivability. Summary of the Invention

[0004] This application aims to provide a method, system, device, and medium for controlling boost pressure in an engine. By predicting the trend of pressure deviation sequences, it accurately identifies low boost pressure faults and adaptively increases the target boost pressure according to the fault severity and engine operating conditions. Simultaneously, it establishes multiple safety exit mechanisms, thereby optimizing the engine's power response and torque accuracy while ensuring the safety of the boost system. To achieve the above objectives, this application adopts the following technical solution.

[0005] In a first aspect, embodiments of this application provide a boost pressure control method for an engine, comprising:

[0006] Obtain the target boost pressure and the actual boost pressure of the engine, and calculate the pressure deviation based on the difference between the two.

[0007] When the preset diagnostic activation condition is triggered, the pressure deviation is collected for multiple consecutive sampling periods to construct a pressure deviation sequence, and the pressure deviation sequence is estimated by a trend prediction model based on the historical and current values ​​in the pressure deviation sequence.

[0008] Based on the deviation of the estimated pressure deviation sequence from the preset dynamic threshold, it is determined whether a fault of low boost pressure has occurred.

[0009] When a fault of low boost pressure is detected, the target boost pressure is selectively increased according to the degree of the fault, and the boost actuator is controlled in a closed loop based on the adjusted target boost pressure.

[0010] When the preset exit condition is detected to be met, the increase of the target boost pressure is terminated, and the target boost pressure is restored to its original value when no malfunction occurred.

[0011] Furthermore, the trend prediction model is a time-series-based prediction model, which calculates the estimated pressure deviation for the next sampling period based on the pressure deviation of the current sampling period and the changing trends of historical pressure deviations using the following formula:

[0012]

[0013] in, Indicates the adaptive trend filtering time; , They represent the (th) ) and the ( The historical values ​​of actual pressure deviation at each sampling point; Indicates the first Estimated pressure deviation at each sampling point; Indicates the sampling period.

[0014] Furthermore, the step of selectively increasing the target boost pressure according to the degree of failure further includes:

[0015] Depending on whether the engine is in fuel cut-off mode, the correction coefficient K2 is determined from different preset mapping relationships; where, when the engine is in fuel cut-off activation condition, a relatively large correction coefficient is selected; when the engine is in non-fuel cut-off condition, a relatively small correction coefficient is selected.

[0016] Based on the difference between the current estimated value and the current actual pressure deviation value in the estimated pressure deviation sequence, and the correction coefficient K2, the pressure compensation amount is calculated, and the pressure compensation amount is superimposed on the target boost pressure to obtain the corrected target boost pressure.

[0017] Based on the corrected target boost pressure, the corresponding target intake pressure is determined in reverse, and the throttle opening is controlled based on the target intake pressure.

[0018] Furthermore, the preset exit condition includes at least one of the following:

[0019] Condition 1: The diagnostic activation condition changes from a satisfied state to a dissatisfied state, and the duration of the dissatisfied state exceeds a first time threshold.

[0020] Condition 2: The throttle opening determined based on the original target boost pressure is lower than the opening threshold associated with the current engine speed for the first time;

[0021] Condition 3: The ratio of the actual air volume of the current engine to the maximum allowable air volume of the system exceeds the air volume ratio threshold associated with the boost pressure ratio and engine speed for the first time.

[0022] Furthermore, it also includes the step of adaptively updating the sampling number V1 used to construct the pressure deviation sequence:

[0023] After determining that a low boost pressure fault has occurred during this driving cycle, the sampling count V1 is updated and the updated V1 value is used in subsequent diagnostics of this driving cycle. The updated V1 value is saved after the vehicle is powered off and used as the initial diagnostic parameter for subsequent driving cycles.

[0024] Furthermore, when exiting via condition one, the method for restoring the target boost pressure to its original value includes:

[0025] The increased target boost pressure is gradually reduced to the original target boost pressure using a preset gradual rate; and if the conditions for increasing the target boost pressure are met again during the gradual reduction process, the sampling number V1 is updated and the pressure increase is performed again.

[0026] Furthermore, the diagnostic activation conditions include all of the following:

[0027] The engine intake air volume based on boost control has not reached the maximum allowable air volume limit of the system; wherein, the maximum air volume limit is dynamically determined by the air volume control method of the exhaust gas turbocharger system;

[0028] The fluctuation range of the target boost pressure is lower than the first preset threshold.

[0029] The absolute value of the rate of change of engine speed is not lower than the second preset threshold.

[0030] The absolute value of the rate of change of fresh air intake density entering the cylinder is not lower than the third preset threshold.

[0031] The rate of change of the opening degree of the booster actuator is not higher than the fourth preset threshold, and the direction of the opening degree change is the increasing direction;

[0032] The engine is not in a state of knocking or pre-ignition;

[0033] The engine exhaust temperature is lower than the preset temperature limit;

[0034] There are no faults in the intake system components.

[0035] Furthermore, the rate of change of the correction coefficient K2 when switching between engine fuel cut-off mode and non-fuel cut-off mode is limited:

[0036] The maximum absolute value of the rate of change is determined by the current engine speed and atmospheric pressure, and satisfies the following condition: the lower the engine speed or the lower the atmospheric pressure, the greater the maximum absolute value of the rate of change.

[0037] Secondly, embodiments of this application provide a boost pressure control system for an engine, comprising:

[0038] The data acquisition module is configured to acquire the engine's target boost pressure and actual boost pressure, and calculate the pressure deviation based on the difference between the two.

[0039] The operating condition enable module is configured to monitor engine operating parameters, determine whether preset diagnostic activation conditions are met, and generate a diagnostic start signal after the preset conditions are met for a continuous period of time.

[0040] The fault diagnosis module is communicatively connected to the data acquisition module and the operating condition enable module. It is configured to respond to the diagnosis start signal, collect pressure deviations for multiple consecutive sampling periods to construct a pressure deviation sequence, calculate an estimated pressure deviation sequence based on a trend prediction model, and then determine whether a low boost pressure fault has occurred based on the deviation of the estimated pressure deviation sequence from a preset dynamic threshold.

[0041] The post-processing control module is communicatively connected to the fault diagnosis module and is configured to selectively increase the target boost pressure according to the degree of the fault when it is determined that the boost pressure is too low, and generate a corrected target boost pressure.

[0042] The actuator drive module is communicatively connected to the post-processing control module and is configured to drive the booster actuator to perform closed-loop control according to the corrected target booster pressure.

[0043] The post-processing control module is further configured to terminate the increase of the target boost pressure and control the target boost pressure to return to its original value when no fault occurred when a preset exit condition is detected.

[0044] Thirdly, embodiments of this application provide an electronic device, including: one or more processors;

[0045] A memory for storing one or more programs; when the one or more programs are executed by the one or more processors, the one or more processors are able to implement the steps in the boost pressure control method described in any of the preceding claims.

[0046] Fourthly, embodiments of this application provide a computer-readable medium storing a computer program, which, when executed by a processor, can implement the steps in the pressurization control method described in any of the preceding claims.

[0047] This application discloses a boost pressure control method for an engine. It calculates the pressure deviation by acquiring the target boost pressure and the actual boost pressure. When diagnostic activation conditions are met, it collects pressure deviations from multiple consecutive sampling periods to form a sequence, and uses a trend prediction model to calculate an estimated pressure deviation sequence. When the estimated sequence continuously shows a negative deviation and the proportion exceeding the dynamic threshold reaches a preset value, a low boost pressure fault is identified. In response to this fault, the target boost pressure is selectively increased based on whether the engine is in fuel cut-off mode, and closed-loop control is performed on the boost actuator. Simultaneously, when the diagnostic conditions disappear, the throttle opening is too low, or the air-fuel ratio exceeds the limit, the system safely exits and restores the original pressure. This application can accurately identify the trend of insufficient boost pressure, adaptively compensate for pressure loss, and optimize torque response while ensuring the safety of the booster, thereby improving engine drivability and robustness. Attached Figure Description

[0048] Figure 1 A core flowchart of a boost pressure control method for an engine provided in an embodiment of this application;

[0049] Figure 2 A schematic diagram of a module structure for a boost pressure control system for an engine, provided as an embodiment of this application;

[0050] Figure 3 This is a structural block diagram of an electronic device provided in an embodiment of this application. Detailed Implementation

[0051] To enable those skilled in the art to better understand the technical solutions of this application, exemplary embodiments of this application are described below with reference to the accompanying drawings, including various details of the embodiments of this application to aid understanding. These should be considered merely exemplary. Therefore, those skilled in the art should recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of this application. Similarly, for clarity and conciseness, descriptions of well-known functions and structures are omitted in the following description. Unless otherwise specified, the various embodiments of this application and the features within those embodiments can be combined with each other.

[0052] As used herein, the term "and / or" includes any and all combinations of one or more of the associated enumerated entries. The terminology used herein is for describing particular embodiments only and is not intended to limit the application. As used herein, the singular forms "a" and "the" are also intended to include the plural forms, unless the context clearly indicates otherwise. It should also be understood that when the terms "comprising" and / or "made of" are used herein, the presence of the stated feature, integral, step, operation, element, and / or component is specified, but the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or groups thereof is not excluded. Terms such as "connected" or "linked" are not limited to physical or mechanical connections but can include electrical connections, whether direct or indirect.

[0053] Unless otherwise specified, all terms used in this application (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art. It should also be understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and this application, and will not be interpreted as having an idealized or overly formal meaning, unless expressly so defined in this application.

[0054] This application provides a boost pressure control method, system, device, and medium for an engine. Its core logic involves: performing fault diagnosis based on trend prediction of pressure deviation sequences, and then adaptively increasing the target boost pressure according to engine operating conditions until the safe exit conditions are met, after which it recovers. (Reference) Figure 1 One embodiment of this application provides a boost pressure control method for an engine, which specifically includes the following core steps.

[0055] Step 1: Data Acquisition and Pressure Deviation Calculation. Specifically, the target boost pressure and the actual boost pressure of the engine are acquired, and the pressure deviation is calculated based on the difference between the two.

[0056] More specifically, during engine operation, the Electronic Control Unit (ECU) first needs to acquire basic data for boost control. Specifically, the ECU calculates the target boost pressure using internal algorithms or lookup tables based on parameters such as current engine speed, intake air volume, and torque request. In this embodiment, this target boost pressure can be obtained using an adaptive optimization control method: first, a basic target pressure is determined based on the engine's intake air volume and air-fuel ratio requirements; then, dynamic corrections are made using boundary conditions such as exhaust temperature and atmospheric pressure to obtain the final target boost pressure, denoted as the first target boost pressure. Meanwhile, the ECU collects the gas pressure in front of the throttle body in real time through a boost pressure sensor installed in front of the throttle body (i.e., between the intercooler and the throttle body), and uses a method based on the actual boost pressure acquisition based on the throttle operating mode to correct and calculate it: that is, depending on whether the throttle body is in normal control mode, anti-overshoot control mode, or fully open control mode, different transition coefficients are selected to weight and fuse the throttle body outlet pressure and inlet pressure to obtain the actual boost pressure. .

[0057] Subsequently, the ECU calculates the difference between the target boost pressure and the actual boost pressure to obtain the pressure deviation. The calculation formula is as follows:

[0058]

[0059] This pressure deviation This is the basic physical quantity for subsequent fault diagnosis. When this value is positive and the absolute value is large, it indicates that the actual boost pressure is significantly lower than the target value, i.e., there is a risk of insufficient boost pressure.

[0060] Step 2: Fault Diagnosis Enable Conditions and Pressure Deviation Sequence Construction. Specifically, when the preset diagnostic activation condition is triggered, the pressure deviations are collected for multiple consecutive sampling periods to construct a pressure deviation sequence. Based on the historical and current values ​​in the pressure deviation sequence, the pressure deviation sequence is estimated using a trend prediction model.

[0061] More specifically, boost pressure fault diagnosis is not suitable under all operating conditions. To avoid misjudgments caused by transient or abnormal conditions, the ECU needs to first determine whether a set of preset "diagnostic activation conditions" are met. In this embodiment, the diagnostic activation conditions include all eight of the following, and all must be met simultaneously:

[0062] 1. Air volume not reaching the upper limit condition: The engine intake air volume based on boost control does not reach the maximum allowable air volume limit of the system. This maximum air volume limit is dynamically determined using an exhaust gas turbocharger system air volume control method: This method calculates the current compressor gas mass flow rate based on parameters such as the maximum air volume density, engine displacement, and engine speed at the previous moment, and combines this with the maximum pressure ratio under steady-state and transient operating conditions to calculate the maximum allowable air volume density under the current operating conditions in real time.

[0063] 2. Target pressure stabilization condition: The target boost pressure The volatility is below a first preset threshold. In this example, the first preset threshold is ±2 kPa, meaning that changes in the target pressure within ±2 kPa are considered stable.

[0064] 3. Engine speed change rate condition: The rate of change of engine speed is not lower than a second preset threshold. In one example, this threshold is set to 10 rpm / ms. This condition ensures that the engine is in a dynamic process, because the problem of insufficient boost capacity is usually only effectively triggered and diagnosed under transient conditions that require acceleration.

[0065] 4. Intake air density change rate condition: Intake air density of fresh air entering the cylinder The rate of change (unit: mg / pl) is not lower than the third preset threshold. In one example, this threshold is 5 mg / ms. The change in intake air density directly reflects the changes in engine load and intake air volume, and its rate of change is an important basis for judging dynamic operating conditions.

[0066] 5. Actuator Opening Change Rate Condition: The opening change rate of the booster actuator (usually an exhaust bypass valve) shall not exceed the fourth preset threshold. In one example, this threshold is -1% / ms. Note that the limitation of "not exceeding" a negative value here means that the actuator opening is allowed to increase at a rate not exceeding 1% / ms (i.e., the actuator is closing to increase exhaust energy to drive the turbine), but it is not allowed to decrease rapidly (i.e., the exhaust bypass valve opens rapidly to release pressure), because the latter indicates a decrease in boost demand and is not suitable for diagnosing low pressure.

[0067] 6. Combustion conditions: The engine is not in a knocking state and is not in a pre-ignition state.

[0068] 7. Thermal load condition: Engine exhaust temperature is lower than the preset temperature limit. In this example, the preset limit is 950℃.

[0069] 8. System health condition: No fault reports are found for intake system components (such as air flow meter, throttle position sensor, etc.).

[0070] When all eight conditions above are met simultaneously, and the duration of this satisfied state exceeds a preset time. (In this example, the timeframe is 0.5 seconds). At this point, the ECU determines that it has entered a stable, diagnosable operating condition and triggers the subsequent diagnostic process. Under this stable operating condition, the ECU begins continuously collecting the most recent data. The sampling period (the sampling period is denoted as) is the next sampling period. In this example, the pressure deviation value is taken over 10 ms to form a pressure deviation array. The initial default value is 9, so 10 pressure deviation values ​​are collected and recorded as follows:

[0071]

[0072] in, This represents the pressure deviation during the current sampling period. This represents the pressure deviation from the previous sampling period, and so on. This represents the pressure deviation from the previous 9th sampling period.

[0073] It is worth noting that the parameters It is not fixed, but rather possesses self-learning and updating capabilities. In this embodiment, The initial value is 9. When a low boost pressure fault is detected during the current driving cycle, the ECU will update according to the fault response strategy. For example, after determining the fault and successfully executing the pressure increase, the ECU will... Updated to And in the subsequent diagnostics of this driving cycle and in the next driving cycle (after the vehicle is powered off, saved, and then powered on again), the new [system / technology] will be used. This adaptive adjustment allows the diagnostic window length to dynamically change with the fault history. When faults occur frequently, the window is expanded to improve diagnostic stability, and when the system is healthy for a long period, the window is reduced to improve diagnostic sensitivity.

[0074] After obtaining the pressure deviation array, the ECU does not directly use the instantaneous values ​​for judgment. Instead, it employs a prediction model based on historical trends to calculate the estimated pressure deviation for each sampling point. This embodiment uses an improved Tustin transform algorithm, and the specific calculation formula is as follows:

[0075]

[0076] The physical meaning of each parameter is as follows:

[0077] : No. Estimated pressure deviation (predicted value) at each sampling point. The value range is 0, 1, 2, ..., .For example, This represents the estimated pressure deviation at the current moment.

[0078] , : respectively the ( ) and the ( The historical values ​​of actual pressure deviation at each sampling point.

[0079] : Sampling period, which is 10 ms in this example.

[0080] The adaptive trend filter time, measured in milliseconds, is not fixed but dynamically adjusted based on the current operating conditions.

[0081] The adaptive trend filtering time The calculation method is as follows:

[0082]

[0083] in:

[0084] : The base value for the trend filter time; in this example, it is set to 50 ms.

[0085] The first correction factor is the ratio of the current pressure deviation to the target boost pressure. With engine speed A defined function. This correction factor is obtained through engine bench calibration: under standard atmospheric pressure, with fixed speeds and loads, this factor is adjusted to maintain the boost pressure difference within ±2 kPa under steady-state conditions. and The difference should not exceed ±2 kPa.

[0086] The second correction factor is based on actual atmospheric pressure. Compared with standard atmospheric pressure (The ratio is taken as 101 kPa in this example) and engine speed A defined function. This coefficient was calibrated on a real vehicle at different altitudes (i.e., different atmospheric pressures). Specifically, when... hour, .

[0087] Using the above formula, the ECU can calculate the estimated value of each element in the pressure deviation array, forming an estimated pressure deviation sequence. .

[0088] Step 3, Fault Judgment Logic. Specifically, after obtaining the estimated pressure deviation sequence, the ECU determines whether a low boost pressure fault has occurred based on the deviation of this sequence from a preset dynamic threshold. The specific judgment logic in this embodiment is as follows:

[0089] If both of the following conditions are met simultaneously, it is determined that a minor fault of low boost pressure has occurred:

[0090] Condition A: For all All satisfy ;

[0091] Condition B: In In the second sampling, the following conditions are met The proportion of sampling times exceeds the preset proportion threshold. (In this example, we take 0.5, which is 50%).

[0092] in, This is the dynamic threshold coefficient for fault diagnosis; in this example, it is set to 0.1. That is, the judgment threshold is proportional to the current target boost pressure, rather than a fixed value. The preset proportional threshold... Adaptive adjustments can also be made based on boundary conditions (such as exhaust temperature approaching a limit). For example, when the exhaust temperature exceeds 900 ℃, it can be temporarily adjusted. Increase it to 0.7 to avoid intervention control at the critical point of heat load.

[0093] In the above judgment logic, the preset dynamic threshold is It is a dynamic threshold that is proportional to the current target boost pressure, rather than a fixed threshold. This ensures that the relative sensitivity of fault triggering remains reasonable under different load conditions (such as high target pressure at low speed and high load, and low target pressure at high speed and low load), avoiding being too sensitive under high load or too sluggish under low load.

[0094] Step 4: Target boost pressure increase strategy after a fault. Specifically, when a fault of low boost pressure is determined to occur, the target boost pressure is selectively increased according to the severity of the fault, and the boost actuator is subjected to closed-loop control based on the adjusted target boost pressure.

[0095] More specifically, once a minor fault of low boost pressure is detected, the ECU immediately enters the after-processing mode and selectively increases the target boost pressure according to the severity of the fault and the current engine operating conditions.

[0096] 1. Correction coefficient The determination

[0097] The ECU first needs to determine the correction factor. This coefficient is selected from different preset mapping relationships based on whether the engine is in fuel cut-off mode:

[0098] When the engine is operating under non-fuel-cut-off conditions (i.e., normal fuel injection): the exhaust system has higher energy and stronger boost capacity. In this case, a relatively small correction factor is used, denoted as... ,in Engine speed, This refers to the intake density of fresh air entering the cylinder. The table below provides a specific example (Table 1).

[0099] Table 1 Correction coefficient table under non-fuel cut-off mode

[0100]

[0101] When the engine is in a fuel cut-off activation condition (such as fuel cut-off during coasting or deceleration): exhaust energy is low and boost capacity is limited. In this case, a relatively large correction factor is used, denoted as... The following table provides a specific example (Table 2):

[0102] Table 2 Correction coefficients under fuel cut-off mode

[0103]

[0104] 2. Calculation of pressure compensation and correction of target pressure

[0105] In determining Then, the ECU calculates the pressure compensation amount and adds it to the original target boost pressure to obtain the corrected target boost pressure. The calculation formula is:

[0106]

[0107] in, Estimate the pressure deviation for the current (or most recent) valid time. This corresponds to the actual pressure deviation. The difference between the two reflects the magnitude of the current prediction error, multiplied by... The compensation amount was then obtained.

[0108] To ensure smooth torque output, the ECU adjusts the correction coefficient when switching between fuel cut-off and non-fuel cut-off modes. The rate of change is limited. The maximum absolute value of this rate of change is determined by the current engine speed. and atmospheric pressure This is jointly determined and satisfies the following condition: the lower the engine speed or the lower the atmospheric pressure, the greater the maximum absolute value of this rate of change. The following table provides a specific calibration example (Table 3):

[0109] Table 3 Table of maximum absolute values ​​of rate of change

[0110]

[0111] The calibration is based on ensuring the engine control torque accuracy is within ±5 Nm. For example, under high-altitude starting conditions with low engine speed (850 rpm) and low atmospheric pressure (80 kPa), it is permissible to... It changes at a relatively fast rate (0.20 NA / ms) to quickly compensate for insufficient boost; while at high speeds (5700 rpm) and standard atmospheric pressure (101 kPa), the rate of change is limited to only 0.01 NA / ms to ensure driving smoothness.

[0112] 3. Coordinated control of boost pressure and intake pressure

[0113] Obtain the corrected target boost pressure Subsequently, the ECU does not directly output this pressure value as a command to the boost actuator. Instead, this embodiment employs a coordinated control strategy: the ECU determines a corresponding target intake pressure (i.e., the target pressure after the throttle) based on the corrected target boost pressure. Specifically, the reverse calculation method can utilize a known technique: based on parameters such as the target boost pressure, the gas temperature at the compressor inlet on the booster's intake side, and the gas pressure and temperature before the throttle, the target intake pressure is deduced by solving the compressor characteristic equation. Then, the ECU drives the throttle actuator based on this reverse-determined target intake pressure to adjust the throttle opening, thereby ensuring that the intake volume matches the new boost pressure and achieving coordinated control of the air path and the boost path.

[0114] Step 5: Post-processing exit mechanism. Specifically, when the preset exit condition is detected to be met, the increase of the target boost pressure is terminated, and the target boost pressure is restored to its original value before the fault occurred.

[0115] More specifically, after the target boost pressure is increased, the ECU needs to continuously monitor a series of exit conditions to prevent over-boosting. This embodiment sets three independent exit conditions; when any one condition is met, the ECU stops increasing the target boost pressure and restores it to its original value. The exit conditions include:

[0116] Condition 1 (Time Condition): The diagnostic activation condition (i.e., the aforementioned 8 steady-state conditions) changes from a satisfied state to a dissatisfied state, and the duration of the dissatisfied state exceeds the first time threshold. In this example Take 0.1 seconds.

[0117] Condition 2 (Throttle opening condition): Based on the original target boost pressure The given throttle opening is lower than the opening threshold associated with the current engine speed for the first time. The aforementioned With engine speed The relationships are shown in the table below (Table 4):

[0118] Table 4 Throttle opening thresholds With rotational speed Relationship table

[0119]

[0120] Condition 3 (Gas Quantity Ratio Condition): The ratio of the actual air volume of the current engine to the maximum allowable air volume of the system exceeds the boost pressure ratio for the first time. and engine speed Associated gas volume ratio threshold Among them, the boost pressure ratio Defined as the ratio of the actual boost pressure to the actual compressor inlet pressure. Threshold. The calibration is shown in the table below (Table 5):

[0121] Table 5 Gas volume ratio threshold and and Relationship table

[0122]

[0123] When the above condition one (diagnostic activation condition not met for more than [time period]) is met... When the boost is triggered and exited, the ECU employs a smooth recovery method to avoid sudden changes in target pressure impacting torque. Specifically, the ECU applies the increased target boost pressure at a preset gradual rate (0.1 kPa / s in this example). Gradually reduce to the original target boost pressure During this gradual reduction process, the ECU continues to monitor the fault diagnosis conditions. If, during the gradual reduction, the engine operating conditions again meet the diagnostic activation conditions and a low boost pressure fault is re-determined, the ECU immediately stops the gradual reduction and re-executes the aforementioned pressure increase strategy. Simultaneously, the ECU will record the number of samplings. Updated to (For example, updating from 9 to 8), and immediately using the new one. The value is used for subsequent diagnosis to improve diagnostic sensitivity.

[0124] refer to Figure 2 One embodiment of this application also provides a boost pressure control system for an engine, used to execute the aforementioned boost pressure control method. This system uses an engine electronic control unit (ECU) as its core and is implemented through modular software functions. The hardware requirements, data interaction, and specific workflow of each module are described in detail below.

[0125] 1. Data Acquisition Module

[0126] The module is physically based on the ECU's input signal processing circuit and internal random access memory (RAM). Its configuration involves receiving data in real-time from the intake manifold pressure sensor, boost pressure sensor (located before the throttle), atmospheric pressure sensor, engine speed sensor, and air flow meter via sensor interfaces, and then storing the data in a designated memory unit after analog-to-digital conversion, filtering, and diagnostics.

[0127] The specific workflow is as follows: First, based on the current engine speed, intake air volume, throttle opening, and torque request, the basic target boost pressure is calculated using an internal torque structure model. This calculation process combines open-loop estimation based on intake air density and charging efficiency with closed-loop correction based on torque deviation. For example, the boost pressure requirement is first derived from the intake manifold target pressure, and then a safety limit is applied based on exhaust temperature and knock boundaries to finally obtain the target boost pressure. Secondly, different transition coefficients are selected based on the throttle operating mode (normal control, overshoot prevention control, full-open control). Throttle outlet pressure sensor signal With throttle inlet pressure sensor signal Perform weighted fusion: The actual boost pressure is obtained. Finally, the pressure deviation is calculated. The deviation value and its sampling timestamp are stored in a circular buffer for subsequent modules to access.

[0128] 2. Operating Condition Enable Module

[0129] This module is implemented by the state machine logic inside the ECU. Its core function is to continuously monitor the engine operating parameters, determine whether the aforementioned 8 diagnostic activation conditions are met simultaneously, and output a diagnostic start flag after the preset time (0.5 seconds in this example) is met continuously.

[0130] The specific implementation details are as follows: The ECU performs the following checks every 10 ms:

[0131] Condition 1: Calculate the current intake volume in real time and compare it with the maximum allowable intake volume calculated by the maximum air volume density model (obtained by interpolation based on the compressor characteristic diagram) to confirm that the current limit has not been reached.

[0132] Condition 2: Target boost pressure If the absolute value of the first-order difference is less than 2 kPa for three consecutive periods, it is considered stable.

[0133] Condition 3: Perform differential calculation on the engine speed signal to obtain the speed change rate, take its absolute value, and determine whether it is less than 10 rpm / ms.

[0134] Condition 4: Regarding intake air density (Calculated from intake manifold pressure and temperature) Take the differential, take its absolute value, and determine whether it is less than 5 mg / ms.

[0135] Condition 5: Obtain the actual opening feedback signal of the booster actuator (exhaust gas bypass valve), calculate its rate of change, and determine whether it is greater than -1% / ms (i.e., it does not close at a rate exceeding 1% / ms). At the same time, detect whether the opening shows an increasing trend (this can be determined by comparing the values ​​before and after low-pass filtering the opening signal).

[0136] Condition 6: Read the knock intensity value and pre-ignition detection mark fed back by the knock sensor, and confirm that both are 0 (no fault).

[0137] Condition 7: Read the exhaust temperature sensor signal and confirm that it is below 950 ℃.

[0138] Condition 8: Read the fault codes (DTCs) of the relevant components of the intake system to confirm that there are no current faults.

[0139] When all eight conditions are met, the enable counter increments by 1; if any condition is not met, the counter is reset to zero. When the counter value reaches 50 (corresponding to 0.5 seconds), the state machine transitions to the "diagnostic enable" state and outputs the diagnostic start flag as "1". This flag will be latched until it is reset when any condition is not met, causing the counter to reset to zero.

[0140] 3. Fault Diagnosis Module

[0141] This module communicates with the data acquisition module and the operating condition enable module. When it receives the diagnostic start flag (=1), the module begins to execute the fault diagnosis logic. It integrates the aforementioned trend prediction model internally.

[0142] The specific implementation method is as follows: First, read the most recent data from the pressure deviation circular buffer of the data acquisition module. Next (default) The pressure deviation value (which can be read from EEPROM and dynamically updated) is formed into an array. Then, for arrive The pressure deviation is estimated using the following formulas in sequence:

[0143]

[0144] in, , , and Each through the current and and speed The sequence is obtained by looking up a table (the table is stored in ROM during the bench calibration phase). After calculation, the estimated sequence is obtained. .

[0145] Next, the module performs the logical operation for fault determination: determining whether all faults are present. And the statistics satisfy The number of, if the number is equal to If the ratio is greater than 0.5, it is determined to be a minor fault of low boost pressure, and the fault flag is output as "1"; otherwise, "0" is output. This fault flag will trigger the post-processing control module and will also be used to trigger... Self-learning and updating.

[0146] 4. Post-processing control module

[0147] This module communicates with the fault diagnosis module. When a fault flag "1" is received, the module is immediately activated and enters the pressure compensation control mode. Internally, it contains a state machine with three sub-states: "pressure increase activation", "pressure hold", and "pressure slow descent recovery".

[0148] The specific workflow is as follows:

[0149] Entering pressure boost activation state: First, check if the engine is currently in fuel cut-off mode. If not, select Table 1 (non-fuel cut-off mode) mentioned above. Determine the correction factor by referring to the table. If fuel cutoff is activated, select the option listed in Table 2 (Fuel Cutoff Mode). Determine by referring to the table. Then, read the most recent valid estimate of pressure deviation. Deviation from actual pressure Calculate the pressure compensation amount Finally, the corrected target boost pressure is calculated. To prevent excessively large single corrections, A pressure limit is applied (e.g., not exceeding 10 kPa). After generating the new target pressure, the state machine transitions to the "pressure hold" sub-state.

[0150] Pressure holding sub-state: In this state, the module continuously outputs... Simultaneously, it monitors the aforementioned three exit conditions. If any exit condition is met, it transitions to the "pressure descent recovery" sub-state. If a new fault diagnosis trigger is received again during the hold period (e.g., the fault flag remains at 1 for multiple sampling cycles), the compensation amount is recalculated and updated. (That is, to continue to improve).

[0151] Pressure Decrease Recovery Sub-state: The module enters this state when exit is triggered by condition one (diagnostic enable condition not being met for more than 0.1 seconds). It gradually decreases the output target boost pressure according to a preset rate of change (0.1 kPa / s) until it equals the original target boost pressure. Then the state machine returns to the idle state. If the fault flag "1" is received again during the descent process, it immediately jumps back to the "pressure increase activation state" and resets the sampling count. Updated to (Minimum value not less than 5). When exit is triggered by the aforementioned condition two or three, the module directly steps back to the target pressure. It then immediately returns to the idle state.

[0152] In addition, this module is also responsible for executing the aforementioned collaborative control strategy: in the output At the same time, a reverse calculation function is called. This function obtains the corresponding target intake pressure after the throttle by solving the compressor characteristic equation (or by looking up the pre-calibrated three-dimensional MAP) based on parameters such as the target boost pressure, the gas temperature before the compressor, and the pressure before the throttle. The target intake pressure is then sent to the throttle controller to achieve a closed-loop air circuit.

[0153] 5. Actuator drive module

[0154] This module communicates with the post-processing control module. Its core is a PID closed-loop controller and a PWM signal generation circuit. Specifically, this module receives the corrected target boost pressure output from the post-processing control module. This serves as the target value for closed-loop control, while simultaneously reading the actual boost pressure in real time. As feedback, the PID controller calculates the deviation between the two and outputs a control quantity. This control quantity, after being limited and protected against integral saturation, is mapped to a PWM duty cycle command for the exhaust bypass valve actuator. The drive circuit converts this command into a current signal capable of driving the solenoid valve, directly controlling the opening of the exhaust bypass valve, thereby changing the exhaust gas flow rate into the turbine and adjusting the boost pressure. Simultaneously, this module also has a fault diagnosis function: if an actuator circuit open circuit, short circuit, or an actual opening degree that does not match the command for an extended period is detected, an actuator fault will be reported to the upper-level fault management module.

[0155] 6. Self-learning module and storage module

[0156] The system allocates a dedicated storage area in the non-volatile memory (EEPROM) to store the self-learning parameters. (Number of samplings). Each time the vehicle is powered on, the ECU reads from the EEPROM. The saved value is used as the initial value. During operation, when the fault diagnosis module determines that a fault has occurred and the post-processing control module successfully executes the pressure increase, the post-processing control module calls the self-learning update function: [The function is then used to update the value]. Assigned value (The upper limit is set to 15), and the new value is written to the EEPROM. Conversely, if no fault diagnosis is triggered for 10 consecutive driving cycles, the system will... Decrement by 1 (lower limit set to 5) and save. This self-learning value takes effect at the start of the next driving cycle.

[0157] The data flow between the above modules includes:

[0158] The data acquisition module outputs a pressure deviation array and target / actual pressure to the fault diagnosis module.

[0159] The operating condition enable module outputs a diagnostic start flag to the fault diagnosis module.

[0160] The fault diagnosis module outputs a fault flag to the post-processing control module.

[0161] The post-processing control module outputs the corrected target boost pressure to the actuator drive module.

[0162] The after-treatment control module also outputs the reverse-determined target intake pressure to the throttle control unit.

[0163] There is bidirectional interaction between the post-processing control module and the fault diagnosis module: the fault flag activates the post-processing; the post-processing re-requests the diagnostic results during the descent process.

[0164] The self-learning module (embedded in the post-processing control module) will be updated. Stored in EEPROM and used by the diagnostic module upon the next power-on.

[0165] Through the precise division of labor and tight data coupling described above, this system fully implements the aforementioned methods and steps, forming a closed-loop control system that can adaptively diagnose low boost pressure faults, safely increase boost pressure, and has self-learning capabilities.

[0166] The embodiments of the aforementioned boosting pressure control method and the embodiments of the aforementioned boosting pressure control system are identical or related in technical concept, and can be referenced and learned from each other in terms of technical details and technical effects, which will not be repeated here.

[0167] Overall, the advantages of this application compared to the prior art include:

[0168] 1. Regarding the accuracy and foresight of fault diagnosis

[0169] In existing technologies, a common fixed threshold and integral rate of change are used to determine actuator responsiveness. This is prone to misjudgment or missed judgment under transient engine conditions or sensor noise interference, and it fails to identify the early downward trend of boost pressure. This application constructs a sequence by collecting pressure deviations from multiple consecutive sampling periods and introduces a prediction model based on historical trends (including adaptive filtering time) to calculate and estimate the pressure deviation sequence, shifting the diagnostic basis from instantaneous value assessment to trend assessment. This allows the system to identify the downward trend of boost pressure before it deviates significantly from the target value, while effectively filtering out interference from transient fluctuations. Therefore, it significantly improves the timeliness and accuracy of fault diagnosis while avoiding false alarms.

[0170] 2. Adaptability and operating condition matching of post-processing control

[0171] Existing technologies lack differentiated aftertreatment strategies for different operating conditions (especially fuel cut-off and non-fuel cut-off states), often employing a uniform compensation method. This may result in insufficient compensation and sluggish power response under fuel cut-off conditions with low exhaust energy, while overcompensation and pressure overshoot may occur under non-fuel cut-off conditions with sufficient exhaust energy. This application determines a correction coefficient from different preset mapping relationships based on whether the engine is in a fuel cut-off active state (a larger K2 is used during fuel cut-off, and a smaller K2 is used during non-fuel cut-off), and calculates the pressure compensation amount using the difference between the estimated pressure deviation and the actual pressure deviation. This scenario-specific adaptive compensation strategy matches the boost pressure increase to the actual energy level of the current exhaust system, providing sufficient compensation under conditions requiring rapid pressure build-up, and adjusting smoothly under conditions where the system already has good responsiveness, thereby maintaining the accuracy and stability of boost control across the entire operating range.

[0172] 3. Regarding system security protection and self-optimization capabilities

[0173] In existing technologies, relying on external devices (electric superchargers) to perform diagnostics under specific conditions not only increases system costs but also fails to achieve continuous self-learning and safety protection during normal vehicle operation. This application establishes a multi-independent exit mechanism consisting of diagnostic condition disappearance timeout, throttle opening too low, and air-fuel ratio exceeding limits. It restricts pressure boosting behavior from three dimensions: "fault disappearance," "reduced intake air demand," and "approaching physical limits," effectively preventing hardware damage risks such as compressor overspeed, blockage, or pumping loss caused by excessive boosting. Simultaneously, by self-learning and updating the sampling count V1 based on fault occurrences and saving it across driving cycles, the diagnostic strategy can dynamically adjust as the vehicle ages or component performance deteriorates, achieving adaptive optimization of system protection.

[0174] 4. Regarding the coordinated control of the turbocharging and intake systems

[0175] Existing technologies generally treat boost pressure control and throttle control as two relatively independent loops. When the target boost pressure is adjusted, pressure fluctuations or response delays can easily occur due to a mismatch between boost and intake air. This application, after obtaining the corrected target boost pressure, does not directly use this pressure value as a command for the boost actuator. Instead, it determines the corresponding target intake pressure based on the corrected target boost pressure and controls the throttle opening based on this target intake pressure. This collaborative control strategy of forward-correcting boost pressure and backward-calculating intake pressure ensures that the boost circuit and the intake circuit maintain a unified target orientation at the execution level, avoiding control oscillations or response lags caused by a mismatch between target pressure and intake air flow, thereby further improving the accuracy and smoothness of torque output.

[0176] Based on the same inventive concept, embodiments of this application also provide an electronic device. Figure 3 This is a structural block diagram of an electronic device provided in an embodiment of this application. Figure 3 As shown in the embodiments of this application, an electronic device includes: one or more processors 101, a memory 102, and one or more I / O interfaces 103. The memory 102 stores one or more programs, which, when executed by the one or more processors, cause the one or more processors to implement any of the boost pressure control methods described in the above embodiments; the one or more I / O interfaces 103 are connected between the processor and the memory, configured to enable information interaction between the processor and the memory.

[0177] The processor 101 is a device with data processing capabilities, including but not limited to a central processing unit (CPU); the memory 102 is a device with data storage capabilities, including but not limited to random access memory (RAM, more specifically SDRAM, DDR, etc.), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), and flash memory (FLASH); the I / O interface (read / write interface) 103 is connected between the processor 101 and the memory 102, and can realize information interaction between the processor 101 and the memory 102, including but not limited to a data bus (Bus).

[0178] In some embodiments, the processor 101, memory 102, and I / O interface 103 are interconnected via bus 104, and thus connected to other components of the computing device.

[0179] In some embodiments, the one or more processors 101 include a field-programmable gate array.

[0180] This application also provides a computer-readable medium. The computer-readable medium stores a computer program, which, when executed by a processor, implements the steps of any of the pressure boosting control methods described in the above embodiments. The computer-readable storage medium can be volatile or non-volatile.

[0181] This application also provides a computer program product, including computer-readable code, or a non-volatile computer-readable storage medium carrying computer-readable code. When the computer-readable code is run in the processor of an electronic device, the processor in the electronic device executes the above-described pressure control method.

[0182] Those skilled in the art will understand that all or some of the steps, systems, and apparatuses disclosed above, and their functional modules / units, can be implemented as software, firmware, hardware, or suitable combinations thereof. In hardware implementations, the division between functional modules / units mentioned above does not necessarily correspond to the division of physical components; for example, a physical component may have multiple functions, or a function or step may be performed collaboratively by several physical components. Some or all physical components may be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit (ASIC). Such software can be distributed on a computer-readable storage medium, which may include computer storage media (or non-transitory media) and communication media (or transient media).

[0183] As is known to those skilled in the art, the term computer storage medium includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information, such as computer-readable program instructions, data structures, program modules, or other data. Computer storage media includes, but is not limited to, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), static random access memory (SRAM), flash memory or other memory technologies, portable compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and is accessible to a computer. Furthermore, it is known to those skilled in the art that communication media typically contain computer-readable program instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

[0184] The computer-readable program instructions described herein can be downloaded from computer-readable storage media to various computing / processing devices, or downloaded via a network, such as the Internet, local area network, wide area network, and / or wireless network, to an external computer or external storage device. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards them to the computer-readable storage media in the respective computing / processing device.

[0185] The computer program instructions used to perform the operations of this application may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, status setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, etc., and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The computer-readable program instructions may be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, electronic circuits, such as programmable logic circuits, field-programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), are personalized by utilizing the status information of the computer-readable program instructions. These electronic circuits can execute the computer-readable program instructions to implement various aspects of this application.

[0186] The computer program product described herein can be implemented specifically through hardware, software, or a combination thereof. In one alternative embodiment, the computer program product is specifically embodied in a computer storage medium; in another alternative embodiment, the computer program product is specifically embodied in a software product, such as a software development kit (SDK), etc.

[0187] Various aspects of this application are described herein with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It should 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-readable program instructions.

[0188] These computer-readable program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to produce a machine such that, when executed by the processor of the computer or other programmable data processing apparatus, they create means for implementing the functions / actions specified in one or more blocks of the flowchart and / or block diagram. These computer-readable program instructions can also be stored in a computer-readable storage medium that causes a computer, programmable data processing apparatus, and / or other device to operate in a particular manner; thus, the computer-readable medium storing the instructions comprises an article of manufacture that includes instructions for implementing aspects of the functions / actions specified in one or more blocks of the flowchart and / or block diagram.

[0189] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the instructions executed on the computer, other programmable data processing apparatus, or other device to perform the functions / actions specified in one or more boxes of a flowchart and / or block diagram.

[0190] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of an instruction containing one or more executable instructions for implementing a specified logical function. In some alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0191] Exemplary embodiments have been disclosed in this application, and while specific terminology has been used, it is used only and should be interpreted in a general illustrative sense and is not intended to be limiting. In some embodiments, it will be apparent to those skilled in the art that features, characteristics, and / or elements described in conjunction with particular embodiments may be used alone, or in combination with features, characteristics, and / or elements described in conjunction with other embodiments, unless otherwise expressly indicated. Therefore, those skilled in the art will understand that various changes in form and detail may be made without departing from the scope of this application as set forth by the appended claims.

Claims

1. A method for controlling boost pressure in an engine, characterized in that, include: Obtain the target boost pressure and the actual boost pressure of the engine, and calculate the pressure deviation based on the difference between the two. When the preset diagnostic activation condition is triggered, the pressure deviation is collected for multiple consecutive sampling periods to construct a pressure deviation sequence, and the pressure deviation sequence is estimated by a trend prediction model based on the historical and current values ​​in the pressure deviation sequence. Based on the deviation of the estimated pressure deviation sequence from the preset dynamic threshold, it is determined whether a fault of low boost pressure has occurred. When a fault of low boost pressure is detected, the target boost pressure is selectively increased according to the degree of the fault, and the boost actuator is controlled in a closed loop based on the adjusted target boost pressure. When the preset exit condition is detected to be met, the increase of the target boost pressure is terminated, and the target boost pressure is restored to its original value when no malfunction occurred.

2. The booster pressure control method according to claim 1, characterized in that, The trend prediction model is a time-series-based prediction model. It calculates the estimated pressure deviation for the next sampling period based on the pressure deviation of the current sampling period and the historical pressure deviation trends, using the following formula: ； in, Indicates the adaptive trend filtering time; , They represent the (th) ) and the ( The historical values ​​of actual pressure deviation at each sampling point; Indicates the first Estimated pressure deviation at each sampling point; Indicates the sampling period.

3. The boosting pressure control method according to claim 1, characterized in that, The step of selectively increasing the target boost pressure according to the degree of failure further includes: Depending on whether the engine is in fuel cut-off mode, the correction coefficient K2 is determined from different preset mapping relationships; where, when the engine is in fuel cut-off activation condition, a relatively large correction coefficient is selected; when the engine is in non-fuel cut-off condition, a relatively small correction coefficient is selected. Based on the difference between the current estimated value and the current actual pressure deviation value in the estimated pressure deviation sequence, and the correction coefficient K2, the pressure compensation amount is calculated, and the pressure compensation amount is superimposed on the target boost pressure to obtain the corrected target boost pressure. Based on the corrected target boost pressure, the corresponding target intake pressure is determined in reverse, and the throttle opening is controlled based on the target intake pressure.

4. The booster pressure control method according to claim 1, characterized in that, The preset exit conditions include at least one of the following: Condition 1: The diagnostic activation condition changes from a satisfied state to a dissatisfied state, and the duration of the dissatisfied state exceeds a first time threshold. Condition 2: The throttle opening determined based on the original target boost pressure is lower than the opening threshold associated with the current engine speed for the first time; Condition 3: The ratio of the actual air volume of the current engine to the maximum allowable air volume of the system exceeds the air volume ratio threshold associated with the boost pressure ratio and engine speed for the first time.

5. The booster pressure control method according to claim 1, characterized in that, It also includes the step of adaptively updating the number of samples V1 used to construct the pressure deviation sequence: After determining that a low boost pressure fault has occurred during this driving cycle, the sampling count V1 is updated and the updated V1 value is used in subsequent diagnostics of this driving cycle. The updated V1 value is saved after the vehicle is powered off and used as the initial diagnostic parameter for subsequent driving cycles.

6. The booster pressure control method according to claim 4, characterized in that, When exiting via condition one, the methods for restoring the target boost pressure to its original value include: The increased target boost pressure is gradually reduced to the original target boost pressure using a preset gradual rate; and if the conditions for increasing the target boost pressure are met again during the gradual reduction process, the sampling number V1 is updated and the pressure increase is performed again.

7. The booster pressure control method according to claim 1, characterized in that, The diagnostic activation conditions include all of the following: The engine intake air volume based on boost control has not reached the maximum allowable air volume limit of the system; wherein, the maximum air volume limit is dynamically determined by the air volume control method of the exhaust gas turbocharger system; The fluctuation range of the target boost pressure is lower than the first preset threshold. The absolute value of the rate of change of engine speed is not lower than the second preset threshold. The absolute value of the rate of change of fresh air intake density entering the cylinder is not lower than the third preset threshold. The rate of change of the opening degree of the booster actuator is not higher than the fourth preset threshold, and the direction of the opening degree change is the increasing direction; The engine is not in a state of knocking or pre-ignition; The engine exhaust temperature is lower than the preset temperature limit; There are no faults in the intake system components.

8. A boost pressure control system for an engine, characterized in that, include: The data acquisition module is configured to acquire the engine's target boost pressure and actual boost pressure, and calculate the pressure deviation based on the difference between the two. The operating condition enable module is configured to monitor engine operating parameters, determine whether preset diagnostic activation conditions are met, and generate a diagnostic start signal after the preset conditions are met for a continuous period of time. The fault diagnosis module is communicatively connected to the data acquisition module and the operating condition enable module. It is configured to respond to the diagnosis start signal, collect pressure deviations for multiple consecutive sampling periods to construct a pressure deviation sequence, calculate an estimated pressure deviation sequence based on a trend prediction model, and then determine whether a low boost pressure fault has occurred based on the deviation of the estimated pressure deviation sequence from a preset dynamic threshold. The post-processing control module is communicatively connected to the fault diagnosis module and is configured to selectively increase the target boost pressure according to the degree of the fault when it is determined that the boost pressure is too low, and generate a corrected target boost pressure. The actuator drive module is communicatively connected to the post-processing control module and is configured to drive the booster actuator to perform closed-loop control according to the corrected target booster pressure. The post-processing control module is further configured to terminate the increase of the target boost pressure and control the target boost pressure to return to its original value when no fault occurred when a preset exit condition is detected.

9. An electronic device, characterized in that, include: One or more processors; Memory, used to store one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors are enabled to implement the steps in the boost pressure control method as described in any one of claims 1 to 7.

10. A computer-readable medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it can implement the steps in the boost pressure control method as described in any one of claims 1 to 7.

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