Method, device and equipment for controlling EGR (exhaust gas recirculation) rate and ignition angle of engine and medium

Abstract

The invention discloses an engine EGR rate and ignition angle control method, device and equipment and a medium, and relates to the technical field of hybrid automobiles, the method comprises the steps that a VVT angle mapping table obtained based on engine oil consumption calibration is obtained, and the VVT angle mapping table defines VVT angles of an engine under different working conditions; determining a target VVT angle of the engine based on the VVT angle mapping table; determining an initial EGR rate and an initial ignition angle based on the standard environmental parameters and the target VVT angle; acquiring current environment parameters of the engine; and on the basis of the current environment parameters and the standard environment parameters, collaborative optimization adjustment is conducted on the initial EGR rate and the initial ignition angle, and in the collaborative optimization adjustment process, the target EGR rate and the target ignition angle in the current environment are determined on the basis of the pressure fluctuation rate of the intake manifold.

Description

Technical Field

[0001] This application relates to the field of hybrid vehicle technology, and in particular to a method, device, equipment and medium for controlling engine EGR rate and ignition angle. Background Technology

[0002] In the field of hybrid vehicle engine control, exhaust gas recirculation (EGR) systems are one of the key technologies for improving thermal efficiency and reducing emissions. Currently, the commonly used low-pressure EGR systems typically estimate and control EGR flow based on parameters such as the pressure ratio across the EGR valve, temperature, and upstream and downstream pressures. However, in complex and variable real-world operating environments, especially under non-standard conditions, this method struggles to effectively regulate EGR flow, limiting the effective improvement of the EGR rate across the entire engine operating range, thus affecting further optimization of the engine's overall thermal efficiency.

[0003] Furthermore, existing technologies typically treat EGR rate and ignition angle adjustments as relatively independent processes, lacking a coordinated optimization mechanism. Especially when engine operating conditions change significantly, the ignition angle fails to effectively match the limiting EGR rate. This not only restricts the full utilization of engine performance but may also lead to decreased combustion stability, affecting the overall efficiency of the powertrain. Therefore, a method for controlling engine EGR rate and ignition angle is urgently needed to address the aforementioned problems. Summary of the Invention

[0004] The summary section introduces a series of simplified concepts, which will be further explained in detail in the detailed description section. This summary section is not intended to limit the key and essential technical features of the claimed technical solutions, nor is it intended to determine the scope of protection of the claimed technical solutions.

[0005] This application aims to address the problem of insufficient coordination between EGR rate and ignition angle in existing engine control technologies, making it difficult to adapt to environmental changes. By pre-calibrating the optimal VVT angle and determining initial parameters, and when environmental conditions deviate from standard conditions, the EGR rate and ignition angle are optimized in a coordinated manner based on the intake manifold pressure fluctuation rate. This achieves dynamic optimization and matching of engine parameters under complex operating environments, effectively improving combustion stability and the application range of the ultimate EGR rate, thereby improving the overall vehicle thermal efficiency.

[0006] In a first aspect, this application provides a method for controlling the EGR rate and ignition angle of an engine, including: Obtain a VVT angle mapping table based on engine fuel consumption calibration, wherein the VVT ​​angle mapping table defines the VVT ​​angle of the engine under different operating conditions; Based on the VVT ​​angle mapping table, determine the target VVT angle of the engine; Based on standard environmental parameters and the target VVT angle, determine the initial EGR rate and initial ignition angle; Obtain the engine's current environmental parameters; Based on the current environmental parameters and the standard environmental parameters, the initial EGR rate and initial ignition angle are adjusted collaboratively. During the collaborative adjustment process, the target EGR rate and target ignition angle under the current environment are determined based on the intake manifold pressure fluctuation rate.

[0007] In some implementations, determining the initial EGR rate and initial ignition angle based on standard environmental parameters and the target VVT angle includes: Based on the target VVT angle and the standard environmental parameters, the initial EGR rate corresponding to the target VVT angle and the standard environmental parameters is determined from the first preset mapping relationship between the VVT ​​angle, environmental parameters and EGR rate. Based on the target VVT angle and the standard environmental parameters, the initial ignition angle corresponding to the target VVT angle and the standard environmental parameters is determined from the second preset mapping relationship between the VVT ​​angle, environmental parameters and ignition angle.

[0008] In some implementations, the step of co-optimizing the initial EGR rate and initial ignition angle based on the current environmental parameters and the standard environmental parameters, wherein during the co-optimization process, the target EGR rate and target ignition angle under the current environment are determined based on the intake manifold pressure fluctuation rate, including: Based on the current environmental parameters and the standard environmental parameters, determine the EGR rate adjustment range and the ignition angle adjustment range; Based on the EGR rate adjustment range and the ignition angle adjustment range, a set of candidate parameter groups is generated, wherein each candidate parameter group includes a candidate EGR rate and a candidate ignition angle; For each candidate parameter group in the candidate parameter group set, the engine is controlled to operate based on the candidate EGR rate and candidate ignition angle in the candidate parameter group; the intake manifold pressure data corresponding to the engine operating based on the candidate parameter group is obtained, and the intake manifold pressure fluctuation rate corresponding to the candidate parameter group is calculated based on the intake manifold pressure data; Based on the intake manifold pressure fluctuation rate corresponding to each candidate parameter group in the calculated candidate parameter group set, the target parameter group corresponding to the minimum intake manifold pressure fluctuation rate is determined. Based on the target parameter set corresponding to the minimum intake manifold pressure fluctuation rate, the target EGR rate and the target ignition angle are determined under the current environment.

[0009] In some implementations, determining the EGR rate adjustment range and the ignition angle adjustment range based on the current environmental parameters and the standard environmental parameters includes: Based on the deviation between the current environmental parameters and the standard environmental parameters, a first adjustment amount corresponding to the EGR rate is determined, wherein the first adjustment amount is used to represent the adjustment range of the EGR rate; based on the first adjustment amount and the initial EGR rate, the EGR rate adjustment range is determined. Based on the deviation between the current environmental parameters and the standard environmental parameters, a second adjustment amount corresponding to the ignition angle is determined, wherein the second adjustment amount is used to represent the adjustment range of the ignition angle; based on the second adjustment amount and the initial ignition angle, the ignition angle adjustment range is determined.

[0010] In some implementations, generating a set of candidate parameter groups based on the EGR rate adjustment range and the ignition angle adjustment range includes: Based on the EGR rate adjustment range and the first preset step size, a candidate EGR rate list is determined; Based on the ignition angle adjustment range and the second preset step size, a candidate ignition angle list is determined; Based on the candidate EGR rate list and the candidate ignition angle list, the candidate parameter set is generated.

[0011] In some implementations, the intake manifold pressure data is a sequence of intake manifold pressure values ​​within a preset sampling period, and the step of calculating the intake manifold pressure fluctuation rate corresponding to the candidate parameter group based on the intake manifold pressure data includes: For each candidate parameter group in the candidate parameter group set, based on the intake manifold pressure data corresponding to that candidate parameter group, an average intake pressure value is determined; based on each intake manifold pressure value in the intake manifold pressure data and the average intake pressure value, a pressure deviation value corresponding to each intake manifold pressure value is determined; based on the pressure deviation value corresponding to each intake manifold pressure value, a pressure deviation summation is determined; based on the pressure deviation summation and the length of the intake manifold pressure data, a pressure standard deviation is determined; based on the ratio of the pressure standard deviation to the average intake pressure value, the intake manifold pressure fluctuation rate corresponding to that candidate parameter group is determined.

[0012] In some implementations, the standard environmental parameters include standard atmospheric pressure, standard ambient temperature, standard intake air temperature, and standard water temperature.

[0013] Secondly, this application proposes a control device for engine EGR rate and ignition angle, comprising: An angle mapping acquisition unit is used to acquire a VVT angle mapping table based on engine fuel consumption calibration, wherein the VVT ​​angle mapping table defines the VVT ​​angle of the engine under different operating conditions. The target angle determination unit is used to determine the target VVT angle of the engine based on the VVT ​​angle mapping table. The initial parameter determination unit is used to determine the initial EGR rate and the initial ignition angle based on standard environmental parameters and the target VVT angle; External parameter acquisition unit, used to acquire the engine's current environmental parameters; The target parameter determination unit is used to perform coordinated optimization adjustment of the initial EGR rate and the initial ignition angle based on the current environmental parameters and the standard environmental parameters. During the coordinated optimization adjustment process, the target EGR rate and the target ignition angle of the current environment are determined based on the intake manifold pressure fluctuation rate.

[0014] Thirdly, an electronic device includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program stored in the memory to implement the steps of the engine EGR rate and ignition angle control method of any of the first aspects.

[0015] Fourthly, this application also proposes a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, it implements the steps of the engine EGR rate and ignition angle control method of any one of the first aspects.

[0016] In summary, the engine EGR rate and ignition angle control method provided in this application establishes an optimal valve timing basis for the engine across all operating conditions by acquiring a VVT angle mapping table based on engine fuel consumption calibration and determining the target VVT angle. Furthermore, it combines standard environmental parameters to determine the initial EGR rate and ignition angle, providing an initial benchmark for the control process. Finally, by acquiring current environmental parameters and coordinating the optimization adjustment of the initial EGR rate and ignition angle based on their differences from standard environmental parameters, and using intake manifold pressure fluctuation rate as the optimization target, the optimal EGR rate and ignition angle combination under the current environment is determined. This method effectively improves the EGR rate control accuracy and ignition angle matching degree of the engine under different environmental conditions, enhances combustion stability, and thus achieves a comprehensive improvement in engine thermal efficiency performance. Attached Figure Description

[0017] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit this specification. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 A schematic flowchart of a method for controlling engine EGR rate and ignition angle provided in an embodiment of this application; Figure 2 A schematic diagram of a control device for engine EGR rate and ignition angle provided in an embodiment of this application; Figure 3 This is a schematic diagram of an electronic control device for controlling the EGR rate and ignition angle of an engine, provided in an embodiment of this application. Detailed Implementation

[0018] The terms "first," "second," "third," "fourth," etc. (if present) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in a sequence other than that illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus. The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them.

[0019] Please see Figure 1 This is a schematic flowchart illustrating a method for controlling engine EGR rate and ignition angle according to an embodiment of this application, which may specifically include: S110. Obtain the VVT ​​angle mapping table based on the engine fuel consumption calibration, wherein the VVT ​​angle mapping table defines the VVT ​​angle of the engine under different operating conditions. For example, in the engine control of hybrid electric vehicles, variable valve timing (VVT) technology optimizes the intake process by adjusting the valve opening and closing timing, playing a crucial role in improving combustion efficiency. Fuel consumption data under different engine speeds and load conditions is obtained through engine bench testing, and a VVT angle mapping table is generated based on the principle of optimal fuel consumption. This mapping table is stored in two-dimensional data format, with engine speed on the horizontal axis and engine load on the vertical axis. Each coordinate point in the table corresponds to the VVT ​​angle value with the lowest fuel consumption under that operating condition, providing basic parameter configuration for subsequent optimized control of EGR rate and ignition angle.

[0020] S120. Based on the VVT ​​angle mapping table, determine the target VVT angle of the engine; For example, a single VVT ​​angle setting value applicable to the entire engine operating range is extracted from a pre-calibrated VVT angle mapping table. This setting value is a fixed parameter determined based on the principle of optimal fuel consumption across the entire engine range. This globally optimal VVT angle setting value is used as the target VVT angle uniformly adopted by the engine under all operating conditions, thereby achieving a fixed configuration of the engine cam profile and establishing a stable valve timing basis for the subsequent coordinated control of EGR rate and ignition angle.

[0021] S130. Based on standard environmental parameters and the target VVT angle, determine the initial EGR rate and initial ignition angle; For example, after determining the target VVT angle, the initial EGR rate and initial ignition angle are determined in conjunction with standard environmental parameters. Standard environmental parameters include baseline values ​​under laboratory calibration conditions such as standard atmospheric pressure, standard ambient temperature, standard intake air temperature, and standard water temperature. Based on these standard parameters and the determined target VVT angle, the corresponding initial EGR rate and initial ignition angle are directly obtained through a preset mapping relationship.

[0022] S140. Obtain the current environmental parameters of the engine; For example, during engine operation, real-time acquisition of various physical parameters in the current environment is a prerequisite for implementing precise control. These parameters typically include, but are not limited to, atmospheric pressure, ambient temperature, intake air temperature, and engine coolant temperature. The values ​​of these parameters are continuously monitored through a sensor network deployed in the engine intake system and the vehicle environment.

[0023] S150. Based on the current environmental parameters and standard environmental parameters, the initial EGR rate and initial ignition angle are adjusted collaboratively. During the collaborative adjustment process, the target EGR rate and target ignition angle under the current environment are determined based on the intake manifold pressure fluctuation rate.

[0024] For example, when the engine operating environment deviates from the standard state, the initial EGR rate and initial ignition angle are adjusted collaboratively based on the differences between the current environmental parameters and the standard environmental parameters. This optimization process involves traversing candidate parameter combinations determined by the adjustment range and collecting intake manifold pressure data of the engine during operation of each candidate parameter group. By calculating the intake manifold pressure fluctuation rate, which characterizes combustion stability, as an evaluation index, the optimal parameter combination corresponding to the minimum pressure fluctuation rate is finally selected, thereby determining the target EGR rate and target ignition angle under the current actual environment.

[0025] In summary, this application establishes a stable valve control foundation for the engine by acquiring a VVT angle mapping table based on optimal engine fuel consumption calibration and determining a target VVT angle applicable to all operating conditions. Furthermore, it combines standard environmental parameters to determine the initial EGR rate and ignition angle, providing reliable benchmark parameters for the control process. Finally, by real-time monitoring of current environmental parameters and adjusting the initial EGR rate and ignition angle collaboratively based on their differences from standard environmental parameters, using intake manifold pressure fluctuation rate as an evaluation index, the optimal parameter combination under the current environment is dynamically determined. This method effectively solves the problem of lack of collaborative optimization between EGR rate and ignition angle under complex operating environments, improving the engine's adaptability and combustion stability under different environmental conditions, thereby achieving a comprehensive improvement in engine thermal efficiency while ensuring power performance.

[0026] In some instances, a VVT angle mapping table based on engine fuel consumption calibration is obtained. This VVT angle mapping table defines the VVT ​​angle of the engine under different operating conditions. Based on the VVT ​​angle mapping table, the target VVT angle of the engine is determined.

[0027] For example, in the engine control process, fuel consumption data under different speeds and loads is first obtained through engine bench testing. Based on the principle of optimal fuel consumption, the variable valve timing angle is calibrated to generate a complete VVT ​​angle mapping table. This mapping table constructs a two-dimensional data matrix with engine speed as the horizontal axis and engine load as the vertical axis. Each coordinate point in the matrix corresponds to the experimentally verified optimal fuel consumption VVT angle value for this specific operating condition. Based on the obtained complete mapping table, the fuel consumption distribution characteristics across the entire MAP operating range are analyzed using a global optimization algorithm. A single VVT ​​angle setpoint applicable to all engine operating conditions is extracted from the mapping table. This setpoint is the globally optimal solution determined after comprehensively considering the fuel consumption performance at each operating point. This globally optimal VVT angle is used as the target VVT angle uniformly adopted by the engine in all operating states, thereby achieving a fixed configuration of the engine valve timing parameters.

[0028] In summary, this application's embodiments, by employing a fixed VVT angle control strategy based on optimal fuel consumption calibration across all operating conditions, establish a stable valve control foundation for the subsequent coordinated optimization of EGR rate and ignition angle. This fixed VVT angle configuration not only simplifies the control system structure and avoids the control complexity caused by dynamically adjusting the VVT ​​angle, but more importantly, ensures that the engine maintains optimal intake characteristics under various operating conditions, creating favorable conditions for the application of the ultimate EGR rate. The fixed valve timing parameters provide stable boundary conditions for the coordinated optimization of EGR rate and ignition angle, enabling the engine to expand the application range of EGR rate while maintaining good combustion stability, thereby laying the foundation for improving overall thermal efficiency.

[0029] In some instances, the engine cam profile is fixed by mechanical locking based on a predetermined target VVT angle. For example, based on the valve opening and closing sequence corresponding to the target VVT angle, a fixed-profile camshaft assembly rigidly connects the camshaft to the drive gear via bolt fastening or interference fit, eliminating the hydraulic or electric adjustment device in the original variable valve timing mechanism. This ensures that the cam profile maintains a fixed phase relationship with the crankshaft, thereby achieving a constant VVT opening angle for the engine across all operating conditions. This mechanical lock-up structure, by eliminating the adjustment function, ensures that the engine maintains the preset optimal valve timing parameters under any operating conditions, providing a stable valve motion reference for the subsequent precise control of EGR rate and ignition angle.

[0030] In summary, the technical solution of fixing the VVT ​​angle by mechanically locking the cam profile in this application effectively eliminates control deviations caused by environmental changes or component aging in variable valve timing, ensuring a high degree of consistency in engine intake characteristics. This fixed design not only improves the reliability and durability of valve timing control, but more importantly, it establishes stable boundary conditions for the coordinated optimization of EGR rate and ignition angle, enabling the engine to achieve higher precision combustion control while maintaining optimal intake efficiency. This mechanical locking structure simplifies the complexity of the control system, reduces the system failure rate, and provides reliable valve control assurance for the application of extreme EGR rates, ultimately laying the hardware foundation for improving engine thermal efficiency.

[0031] In some instances, the initial EGR rate and initial ignition angle are determined based on standard environmental parameters and the target VVT angle, including: Based on the target VVT angle and standard environmental parameters, the initial EGR rate corresponding to the target VVT angle and standard environmental parameters is determined from the first preset mapping relationship between VVT angle, environmental parameters and EGR rate. Based on the target VVT angle and standard environmental parameters, the initial ignition angle corresponding to the target VVT angle and standard environmental parameters is determined from the second preset mapping relationship between the VVT ​​angle, environmental parameters and ignition angle.

[0032] For example, this first preset mapping relationship is established in advance through engine bench testing. It uses a specific combination of VVT angles and standard environmental parameters as input conditions, mapping them to an EGR rate value that has been experimentally verified and can achieve the optimal combustion efficiency under the current operating conditions. Standard environmental parameters typically include baseline operating conditions such as standard atmospheric pressure, standard ambient temperature, standard intake air temperature, and standard coolant temperature. In practical implementation, by querying this first preset mapping relationship, the initial EGR rate setting value corresponding to the current target VVT angle and standard environmental parameters can be directly obtained.

[0033] This second preset mapping relationship is also constructed based on a large amount of engine calibration test data. It establishes the ignition advance angle data corresponding to achieving optimal engine power and economy under fixed VVT angle and standard environmental conditions. The determination process involves matching and searching within the second preset mapping relationship based on the determined target VVT angle and the specific values ​​of various standard environmental parameters, thereby outputting a definite initial ignition angle value. This initial ignition angle, together with the initial EGR rate, constitutes the optimal combustion control parameter pair that matches the fixed VVT angle under standard environmental conditions.

[0034] In summary, the embodiments of this application, through the method of determining initial parameters based on preset mapping relationships, provide a validated parameter benchmark starting point for engine control under standard operating conditions. This not only ensures optimal initial performance of the control system under standard conditions, but more importantly, when the actual operating environment changes, this reliable initial value defines a clear and reasonable optimization space for subsequent collaborative optimization adjustments. This avoids problems such as oscillations in the optimization process or convergence to suboptimal solutions due to excessive initial value deviations, thereby improving the stability, convergence speed, and final environmental adaptability of the entire control system.

[0035] In some instances, the initial EGR rate and initial ignition angle are collaboratively optimized based on current and standard environmental parameters. During this collaborative optimization process, the target EGR rate and target ignition angle under the current environment are determined based on the intake manifold pressure fluctuation rate, including: Based on current environmental parameters and standard environmental parameters, determine the EGR rate adjustment range and ignition angle adjustment range; Based on the EGR rate adjustment range and the ignition angle adjustment range, a set of candidate parameter groups is generated, wherein each candidate parameter group includes a candidate EGR rate and a candidate ignition angle; For each candidate parameter group in the candidate parameter group set, control the engine to operate based on the candidate EGR rate and candidate ignition angle in that candidate parameter group; obtain the intake manifold pressure data corresponding to the engine operation based on the candidate parameter group, and calculate the intake manifold pressure fluctuation rate corresponding to the candidate parameter group based on the intake manifold pressure data; Based on the intake manifold pressure fluctuation rate corresponding to each candidate parameter group in the calculated candidate parameter group set, the target parameter group corresponding to the minimum intake manifold pressure fluctuation rate is determined. Based on the target parameter set corresponding to the minimum intake manifold pressure fluctuation rate, the target EGR rate and target ignition angle are determined under the current environment.

[0036] For example, the collected current environmental parameters, such as actual atmospheric pressure, actual ambient temperature, actual intake air temperature, and actual water temperature, are compared one by one with pre-stored standard environmental parameters to calculate their numerical deviations. Based on these deviations, a first adjustment amount required for the EGR rate and a second adjustment amount required for the ignition angle are determined according to preset adjustment calculation rules. The first adjustment amount defines the range of change of the EGR rate relative to its initial value, while the second adjustment amount defines the range of change of the ignition angle relative to its initial value. Subsequently, using the initial EGR rate as the center and combining it with the first adjustment amount, the upper and lower boundaries of the EGR rate are determined, forming the EGR rate adjustment range; similarly, using the initial ignition angle as the center and combining it with the second adjustment amount, the upper and lower boundaries of the ignition angle are determined, forming the ignition angle adjustment range.

[0037] Based on the EGR rate adjustment range and the ignition angle adjustment range, a candidate parameter set is generated. In this step, according to a preset first adjustment step size, within the determined EGR rate adjustment range, all possible candidate EGR rate values ​​are enumerated at intervals of this step size, forming a candidate EGR rate list. Simultaneously, according to a preset second adjustment step size, within the determined ignition angle adjustment range, all possible candidate ignition angle values ​​are enumerated at intervals of this step size, forming a candidate ignition angle list. Subsequently, each candidate EGR rate in the candidate EGR rate list is paired with each candidate ignition angle in the candidate ignition angle list to generate a candidate parameter set containing all possible parameter combinations, where each candidate parameter set contains a specific candidate EGR rate and a specific candidate ignition angle.

[0038] For each candidate parameter group in the candidate parameter set, the engine is controlled to operate based on the candidate EGR rate and candidate ignition angle of that candidate parameter group, and the corresponding intake manifold pressure data is acquired. The intake manifold pressure fluctuation rate corresponding to that candidate parameter group is then calculated. During implementation, the engine's EGR rate and ignition angle are temporarily adjusted to the values ​​specified in the candidate parameter group, either sequentially or in parallel, and the engine is allowed to operate stably under this setting for a preset sampling period. During this period, the pressure values ​​in the intake manifold are continuously collected by pressure sensors, forming a time series of intake manifold pressure data. Based on this pressure data series, its arithmetic mean is first calculated, then the difference between each pressure data point and this mean is calculated, followed by the sum of squares of these differences. The pressure standard deviation is then calculated based on this sum of squares and the length of the data series. Finally, the pressure standard deviation is divided by the average pressure value to obtain the intake manifold pressure fluctuation rate, which characterizes the combustion stability under this parameter combination.

[0039] Based on the intake manifold pressure fluctuation rate corresponding to each candidate parameter group in the calculated candidate parameter set, the target parameter group corresponding to the minimum intake manifold pressure fluctuation rate is determined. This step compares and analyzes all the calculated intake manifold pressure fluctuation rate values, and selects the one with the smallest value. The specific candidate parameter group corresponding to this minimum value is determined as the target parameter group under the current environment. This target parameter group represents the combination of EGR rate and ignition angle that achieves the most stable engine intake pressure and optimal combustion state within the explored parameter space.

[0040] Based on the target parameter set corresponding to the minimum intake manifold pressure fluctuation rate, the target EGR rate and target ignition angle are determined under the current environment. After determining the target parameter set, the candidate EGR rate values ​​contained in this parameter set are directly identified as the target EGR rate under the current environment, and the candidate ignition angle values ​​contained in this parameter set are also identified as the target ignition angle under the current environment. Thus, the control system obtains optimized control parameters adapted to the specific environmental conditions.

[0041] In summary, this application's embodiments, by traversing the parameter adjustment range determined under environmental deviation guidance and utilizing the intake manifold pressure fluctuation rate—a physical quantity directly reflecting combustion stability—as an objective evaluation index, find the optimal EGR rate and ignition angle combination that matches a fixed VVT angle under different environmental conditions. This method effectively overcomes the initial parameter mismatch problem caused by environmental changes, improving the engine's combustion efficiency and operational stability under various actual operating conditions.

[0042] In some instances, the EGR rate adjustment range and ignition angle adjustment range are determined based on current environmental parameters and standard environmental parameters, including: Based on the deviation between the current environmental parameters and the standard environmental parameters, a first adjustment amount corresponding to the EGR rate is determined, wherein the first adjustment amount is used to represent the adjustment range of the EGR rate; based on the first adjustment amount and the initial EGR rate, the EGR rate adjustment range is determined. Based on the deviation between the current environmental parameters and the standard environmental parameters, a second adjustment amount corresponding to the ignition angle is determined, wherein the second adjustment amount is used to represent the adjustment range of the ignition angle; based on the second adjustment amount and the initial ignition angle, the ignition angle adjustment range is determined.

[0043] For example, based on the numerical deviation between the current environmental parameters and the standard environmental parameters, a first adjustment amount corresponding to the EGR rate and a second adjustment amount corresponding to the ignition angle are determined. Specifically, the standard environmental parameters include standard atmospheric pressure of 101.35 kPa, standard ambient temperature of 25°C, standard intake air temperature of 40°C, and standard water temperature of 90°C. When calculating the deviation, the difference between the current atmospheric pressure and the standard atmospheric pressure is first compared. If the absolute value of this difference is greater than 5 kPa, it is determined that the atmospheric environment has changed significantly, triggering the parameter adjustment mechanism. When the current atmospheric pressure is lower than the standard atmospheric pressure and the deviation exceeds 5 kPa, the first adjustment amount of the EGR rate is determined to be a downward adjustment of 10% of the initial EGR rate, that is, the EGR rate adjustment range is the interval formed by the initial EGR rate to the initial EGR rate reduced by 10%; at the same time, the second adjustment amount of the ignition angle is determined to be an adjustment towards the delayed ignition direction, and its absolute adjustment range is limited by the detonation boundary conditions, with a maximum back-off angle of no more than 2 degrees. When the current atmospheric pressure is higher than the standard atmospheric pressure and the deviation exceeds 5 kPa, while the current intake air temperature is lower than 50°C, the above adjustment mechanism is also triggered. Both the EGR rate and ignition angle adopt a downward learning strategy, meaning the EGR rate adjustment range remains 10% lower than the initial EGR rate, and the ignition angle adjustment range is also constrained by the knock boundary, with a maximum retraction angle not exceeding 2 degrees. If the atmospheric pressure deviation does not exceed 5 kPa, or if it does exceed but the intake air temperature condition is not met, the initial EGR rate and ignition angle settings are maintained, and the optimization adjustment process is not initiated.

[0044] After determining the values ​​of the first and second adjustment amounts, the upper and lower boundaries of the EGR rate adjustment range are calculated based on the initial EGR rate and the first adjustment amount. The lower boundary of the EGR rate adjustment range is calculated by subtracting 10% from the initial EGR rate, and the upper boundary is the initial EGR rate itself, forming a continuous numerical range that fluctuates downwards by 10% from the initial EGR rate. For the ignition angle adjustment range, its lower boundary is calculated by subtracting the maximum backlash limit of 2 degrees from the initial ignition angle, and the upper boundary is the initial ignition angle itself, forming a continuous numerical range that delays backwards by a maximum of 2 degrees from the initial ignition angle. When determining these boundaries, the EGR rate adjustment uses a relative percentage to accommodate differences in the EGR rate baseline value under different operating conditions; while the ignition angle adjustment uses an absolute angle to ensure that its adjustment amount remains consistent under different operating conditions. Through these methods, the adjustment ranges of the EGR rate and ignition angle can accurately reflect the degree of influence of actual environmental changes on the engine combustion process.

[0045] In summary, this application's embodiments provide a precise and reasonable parameter search space for subsequent collaborative optimization by quantifying the deviations between environmental parameters and standard values. The judgment logic, based on atmospheric pressure as the primary factor and intake air temperature as the secondary factor, ensures that the adjustment mechanism is activated only when environmental conditions undergo substantial changes, avoiding unnecessary parameter disturbances. The adjustment ranges of EGR rate and ignition angle are defined using relative and absolute values ​​respectively, considering both the differences in the characteristics of different parameters and ensuring the engineering feasibility of the adjustment process. Using the knock boundary as a hard constraint on ignition angle adjustment effectively prevents engine performance degradation due to excessive ignition angle reduction. This adjustment range determination strategy lays the foundation for achieving EGR rate and ignition angle matching under complex environmental conditions, improving the adaptability and reliability of the control system.

[0046] It should be noted that, among the actual environmental parameters, changes in atmospheric pressure have the most significant impact on engine intake air density and combustion conditions, and are the main basis for triggering and optimizing control parameters. Engine coolant temperature mainly reflects the thermal management status, and because its thermal management system remains relatively stable, it has little impact on control decisions. Changes in ambient temperature are captured in real time by the intake air temperature sensor and reflected in the intake air temperature parameter. Therefore, in environmental deviation analysis, intake air temperature is included as one of the key parameters in comprehensive consideration.

[0047] In some instances, a set of candidate parameter groups is generated based on the EGR rate adjustment range and the ignition angle adjustment range, including: Based on the EGR rate adjustment range and the first preset step size, a list of candidate EGR rates is determined; Based on the ignition angle adjustment range and the second preset step size, a list of candidate ignition angles is determined; Based on the candidate EGR rate list and the candidate ignition angle list, a set of candidate parameter groups is generated.

[0048] For example, a candidate EGR rate list is generated based on a determined EGR rate adjustment range and a preset first adjustment step size. This process first reads the upper and lower boundary values ​​of the EGR rate adjustment range, and then enumerates values ​​within the adjustment range using the first adjustment step size as the increment or decrement interval. The first adjustment step size is a fixed value preset according to engine control accuracy requirements and system computing power, and can be set to 1%. By starting from the lower boundary of the adjustment range and gradually increasing the step size to the upper boundary, an ordered sequence of EGR rates containing all possible candidate values ​​is generated, i.e., the candidate EGR rate list. This list ensures that within a given adjustment range, all EGR rate values ​​distributed according to the step size interval can be included in the subsequent evaluation process.

[0049] In generating the candidate ignition angle list, the system employs similar logic to the steps described above, but adapts it to the characteristics of the ignition angle parameters. Based on the determined ignition angle adjustment range and a preset second adjustment step size, the system performs numerical enumeration. The second adjustment step size is a pre-set angle value based on the requirements for ignition angle control accuracy and combustion stability. Starting from the lower boundary of the ignition angle adjustment range, the system gradually increases the second adjustment step size to the upper boundary of the adjustment range, generating an ordered sequence of ignition angles containing all possible candidate values—the candidate ignition angle list. This list ensures that within the allowed ignition angle adjustment range, all ignition angle values ​​distributed according to angle step size intervals are considered.

[0050] After generating the candidate EGR rate list and candidate ignition angle list, the process of constructing the candidate parameter set begins. This process involves pairing each candidate EGR rate value in the candidate EGR rate list with each candidate ignition angle value in the candidate ignition angle list to form a parameter combination space. Specifically, a traversal algorithm is used. First, a candidate value in the candidate EGR rate list is fixed, and then it is paired sequentially with all candidate values ​​in the candidate ignition angle list. Then, the next candidate value in the candidate EGR rate list is replaced, and the above pairing process is repeated until all candidate values ​​in the candidate EGR rate list have been fully paired with all candidate ignition angle values. The final candidate parameter set is a data structure containing all possible combinations of EGR rate and ignition angle, where each element is a parameter set containing a specific EGR rate value and a specific ignition angle value.

[0051] In summary, the embodiments of this application generate a set of candidate parameter groups using the above method, establishing a complete parameter search space for the subsequent collaborative optimization process. This method ensures that all possible combinations of EGR rate and ignition angle can be included in the evaluation range within the preset adjustment range, avoiding suboptimal solutions caused by missing parameter combinations. Using a fixed step size for parameter enumeration ensures both the comprehensiveness of the search and controls computational complexity through reasonable step size settings. This parameter group generation method provides a solid foundation for optimization evaluation based on intake manifold pressure fluctuation rate, enabling the finally determined target EGR rate and target ignition angle to truly represent the optimal combustion control parameters under current environmental conditions, thereby effectively improving the engine's adaptability and thermal efficiency performance in different environments.

[0052] In some instances, the intake manifold pressure data is a sequence of intake manifold pressure values ​​within a preset sampling period. Based on the intake manifold pressure data, the intake manifold pressure fluctuation rate corresponding to the candidate parameter set is calculated, including: For each candidate parameter group in the candidate parameter group set, the average intake pressure value is determined based on the intake manifold pressure data corresponding to that candidate parameter group; the pressure deviation value corresponding to each intake manifold pressure value is determined based on the intake manifold pressure data and the average intake pressure value; the sum of squares of pressure deviations is determined based on the pressure deviation value corresponding to each intake manifold pressure value; the standard deviation of pressure is determined based on the sum of squares of pressure deviations and the length of the intake manifold pressure data; and the intake manifold pressure fluctuation rate corresponding to that candidate parameter group is determined based on the ratio of the standard deviation of pressure to the average intake pressure value.

[0053] For example, for each candidate parameter group in the candidate parameter set, while the engine operates according to the parameters of that group within a preset sampling period, the intake manifold pressure sensor readings are continuously collected to form a continuous pressure value sequence as the intake manifold pressure data corresponding to that parameter group. First, based on this complete intake manifold pressure data sequence, all pressure values ​​are summed and divided by the total number of data points to calculate the average intake pressure value within that time period. Then, the arithmetic difference between each specific intake manifold pressure value in the pressure data sequence and the aforementioned average intake pressure value is calculated sequentially to obtain the corresponding value for each data point. The pressure deviation value is calculated; then, each pressure deviation value is squared, and the results of all squares are summed to obtain the pressure deviation summation; then, the pressure deviation summation is divided by the length of the intake manifold pressure data sequence, i.e., the total number of data points, and the square root of the quotient is taken to obtain the pressure standard deviation during the operation of the parameter group; finally, the calculated pressure standard deviation is divided by the average intake pressure value mentioned above, and the resulting ratio is the intake manifold pressure fluctuation rate corresponding to the candidate parameter group. This fluctuation rate quantifies the stability of the intake pressure when the engine is running under the current parameter combination.

[0054] Please see Figure 2 This is a schematic diagram of a control device for engine EGR rate and ignition angle provided in an embodiment of this application, including: Angle mapping acquisition unit 21 is used to acquire a VVT angle mapping table based on engine fuel consumption calibration, wherein the VVT ​​angle mapping table defines the VVT ​​angle of the engine under different operating conditions. The target angle determination unit 22 is used to determine the target VVT angle of the engine based on the VVT ​​angle mapping table; The initial parameter determination unit 23 is used to determine the initial EGR rate and initial ignition angle based on standard environmental parameters and the target VVT angle; External parameter acquisition unit 24 is used to acquire the current environmental parameters of the engine; The target parameter determination unit 25 is used to perform coordinated optimization adjustment of the initial EGR rate and initial ignition angle based on the current environmental parameters and standard environmental parameters. During the coordinated optimization adjustment process, the target EGR rate and target ignition angle of the current environment are determined based on the intake manifold pressure fluctuation rate.

[0055] Please see Figure 3 This application also provides an electronic device 300, including a memory 310, a processor 320, and a computer program 311 stored in the memory 310 and executable on the processor. When the processor 320 executes the computer program 311, it implements the steps of the engine EGR rate and ignition angle control method.

[0056] Since the electronic device described in this embodiment is the device used to implement the engine EGR rate and ignition angle control device in the embodiment of this application, those skilled in the art can understand the specific implementation method and various variations of the electronic device in this embodiment based on the method described in the embodiment of this application. Therefore, how the electronic device implements the method in the embodiment of this application will not be described in detail here. Any device used by those skilled in the art to implement the method in the embodiment of this application is within the scope of protection of this application.

[0057] In practice, when the computer program 311 is executed by the processor, it can implement any of the embodiments corresponding to the first aspect.

[0058] It should be noted that the descriptions of each embodiment in the above embodiments have different focuses. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0059] Those skilled in the art will understand that embodiments of this application can provide methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-readable storage media containing computer-readable program code.

[0060] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create a machine for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0061] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0062] These computer program instructions can also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0063] This application also provides a computer program product, which includes computer software instructions that, when executed on a processing device, cause the processing device to perform... Figure 1 The flowchart of a method for controlling engine EGR rate and ignition angle in a corresponding embodiment.

[0064] A computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the flow or function according to the embodiments of this application is generated. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium or transferred from one computer-readable storage medium to another. For example, computer instructions may be transferred from one website, computer, server, or data center to another website, computer, server, or data center via wired or wireless means. The computer-readable storage medium may be any usable medium that a computer can store or a data storage device such as a server or data center that integrates one or more usable media. The usable medium may be a magnetic medium, an optical medium, or a semiconductor medium, etc.

[0065] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0066] In the several embodiments provided in this application, it should be understood that the disclosed devices, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; multiple units or components may be combined or integrated into another system, or some features may be omitted or not performed. Furthermore, the mutual couplings or direct couplings or communication connections shown or discussed may be indirect couplings or communication connections through some interfaces, devices, or units, and may be electrical, mechanical, or other forms.

[0067] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0068] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated units described above can be implemented in the form of hardware and / or software functional units.

[0069] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device to execute all or part of the steps of the methods in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory, magnetic disks, or optical disks.

[0070] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

[0071] Obviously, those skilled in the art can make various modifications to this specification without departing from its spirit and scope. Therefore, this specification also intends to include any modifications that fall within the scope of the claims and their equivalents.

Claims

1. A method for controlling engine EGR rate and ignition angle, characterized in that, include: Obtain a VVT angle mapping table based on engine fuel consumption calibration, wherein the VVT ​​angle mapping table defines the VVT ​​angle of the engine under different operating conditions; Based on the VVT ​​angle mapping table, determine the target VVT angle of the engine; Based on standard environmental parameters and the target VVT angle, determine the initial EGR rate and initial ignition angle; Obtain the engine's current environmental parameters; Based on the current environmental parameters and the standard environmental parameters, the initial EGR rate and initial ignition angle are adjusted collaboratively. During the collaborative adjustment process, the target EGR rate and target ignition angle under the current environment are determined based on the intake manifold pressure fluctuation rate.

2. The method according to claim 1, characterized in that, The determination of the initial EGR rate and initial ignition angle based on standard environmental parameters and the target VVT angle includes: Based on the target VVT angle and the standard environmental parameters, the initial EGR rate corresponding to the target VVT angle and the standard environmental parameters is determined from the first preset mapping relationship between the VVT ​​angle, environmental parameters and EGR rate. Based on the target VVT angle and the standard environmental parameters, the initial ignition angle corresponding to the target VVT angle and the standard environmental parameters is determined from the second preset mapping relationship between the VVT ​​angle, environmental parameters and ignition angle.

3. The method according to claim 1, characterized in that, The step of coordinating and optimizing the initial EGR rate and initial ignition angle based on the current environmental parameters and the standard environmental parameters, and determining the target EGR rate and target ignition angle under the current environment based on the intake manifold pressure fluctuation rate during the coordinating and optimizing adjustment process, includes: Based on the current environmental parameters and the standard environmental parameters, determine the EGR rate adjustment range and the ignition angle adjustment range; Based on the EGR rate adjustment range and the ignition angle adjustment range, a set of candidate parameter groups is generated, wherein each candidate parameter group includes a candidate EGR rate and a candidate ignition angle; For each candidate parameter group in the candidate parameter group set, the engine is controlled to operate based on the candidate EGR rate and candidate ignition angle in the candidate parameter group; the intake manifold pressure data corresponding to the engine operating based on the candidate parameter group is obtained, and the intake manifold pressure fluctuation rate corresponding to the candidate parameter group is calculated based on the intake manifold pressure data; Based on the intake manifold pressure fluctuation rate corresponding to each candidate parameter group in the calculated candidate parameter group set, the target parameter group corresponding to the minimum intake manifold pressure fluctuation rate is determined. Based on the target parameter set corresponding to the minimum intake manifold pressure fluctuation rate, the target EGR rate and the target ignition angle are determined under the current environment.

4. The method according to claim 3, characterized in that, The process of determining the EGR rate adjustment range and ignition angle adjustment range based on the current environmental parameters and the standard environmental parameters includes: Based on the deviation between the current environmental parameters and the standard environmental parameters, a first adjustment amount corresponding to the EGR rate is determined, wherein the first adjustment amount is used to represent the adjustment range of the EGR rate; based on the first adjustment amount and the initial EGR rate, the EGR rate adjustment range is determined. Based on the deviation between the current environmental parameters and the standard environmental parameters, a second adjustment amount corresponding to the ignition angle is determined, wherein the second adjustment amount is used to represent the adjustment range of the ignition angle; based on the second adjustment amount and the initial ignition angle, the ignition angle adjustment range is determined.

5. The method according to claim 3, characterized in that, The process of generating a candidate parameter set based on the EGR rate adjustment range and the ignition angle adjustment range includes: Based on the EGR rate adjustment range and the first preset step size, a candidate EGR rate list is determined; Based on the ignition angle adjustment range and the second preset step size, a candidate ignition angle list is determined; Based on the candidate EGR rate list and the candidate ignition angle list, the candidate parameter set is generated.

6. The method according to claim 3, characterized in that, The intake manifold pressure data is a sequence of intake manifold pressure values ​​within a preset sampling period. The step of calculating the intake manifold pressure fluctuation rate corresponding to the candidate parameter group based on the intake manifold pressure data includes: For each candidate parameter group in the candidate parameter group set, based on the intake manifold pressure data corresponding to that candidate parameter group, an average intake pressure value is determined; based on each intake manifold pressure value in the intake manifold pressure data and the average intake pressure value, a pressure deviation value corresponding to each intake manifold pressure value is determined; based on the pressure deviation value corresponding to each intake manifold pressure value, a pressure deviation summation is determined; based on the pressure deviation summation and the length of the intake manifold pressure data, a pressure standard deviation is determined; based on the ratio of the pressure standard deviation to the average intake pressure value, the intake manifold pressure fluctuation rate corresponding to that candidate parameter group is determined.

7. The method according to claim 1, characterized in that, The standard environmental parameters include standard atmospheric pressure, standard ambient temperature, standard intake air temperature, and standard water temperature.

8. A control device for engine EGR rate and ignition angle, characterized in that, include: An angle mapping acquisition unit is used to acquire a VVT angle mapping table based on engine fuel consumption calibration, wherein the VVT ​​angle mapping table defines the VVT ​​angle of the engine under different operating conditions. The target angle determination unit is used to determine the target VVT angle of the engine based on the VVT ​​angle mapping table. The initial parameter determination unit is used to determine the initial EGR rate and the initial ignition angle based on standard environmental parameters and the target VVT angle; External parameter acquisition unit, used to acquire the engine's current environmental parameters; The target parameter determination unit is used to perform coordinated optimization adjustment of the initial EGR rate and the initial ignition angle based on the current environmental parameters and the standard environmental parameters. During the coordinated optimization adjustment process, the target EGR rate and the target ignition angle of the current environment are determined based on the intake manifold pressure fluctuation rate.

9. An electronic device, comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that the processor executes the computer program stored in the memory to implement the steps of the engine EGR rate and ignition angle control method as described in any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the engine EGR rate and ignition angle control method as described in any one of claims 1 to 7.

Images