Engine combustion control method and related apparatus

Abstract

The application discloses an engine combustion control method, and relates to the technical field of engine control, which comprises the following steps: obtaining a current intercooled mixture temperature at an outlet of an intercooler; when the current intercooled mixture temperature is less than a preset temperature threshold, controlling engine coolant to flow into the intercooler through a heating passage to heat the mixture in the intercooler by using the engine coolant; determining a target ignition angle corresponding to the current intercooled mixture temperature from a preset mapping relationship between the intercooled mixture temperature and the ignition angle based on the current intercooled mixture temperature; and controlling an ignition device to perform an ignition action based on the target ignition angle. The application actively heats the low-temperature mixture by using the engine coolant and synchronously corrects the ignition angle, thereby improving the mixture atomization quality and the combustion rate under a low-temperature working condition, improving the combustion stability, and improving the thermal efficiency of the engine.

Description

Technical Field

[0001] This application relates to the field of engine control technology, and in particular to an engine combustion control method and related equipment. Background Technology

[0002] In the field of engine combustion control, the air-fuel mixture temperature has a significant impact on combustion efficiency and stability. In existing technologies, the pressurized air-fuel mixture is typically cooled by an intercooler to suppress knocking and increase intake air density. However, in low-temperature environments or under cold-start conditions, excessively low mixture temperatures can lead to poor fuel atomization, reduced flame propagation rate, and even misfires or unstable combustion, consequently reducing engine thermal efficiency and worsening emissions. Therefore, there is an urgent need for an engine combustion control method to address the aforementioned technical problems. Summary of the Invention

[0003] 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.

[0004] This application aims to solve the technical problem of unstable combustion and reduced thermal efficiency caused by excessively low air-fuel mixture temperature under low-temperature operating conditions. It obtains the current air-fuel mixture temperature at the intercooler outlet. When this temperature is lower than a preset threshold, the engine coolant is used to heat the mixture. A target ignition angle is determined based on a preset mapping relationship between temperature and ignition angle, and the ignition device is controlled to perform ignition, thereby improving the engine's low-temperature combustion stability.

[0005] In a first aspect, this application provides an engine combustion control method applied to an engine, the engine including an intercooler, an ignition device, and a heating passage for introducing engine coolant into the intercooler, the method comprising: Obtain the current intercooled mixture temperature at the outlet of the intercooler; When the current intercooled air-fuel mixture temperature is lower than a preset temperature threshold, the engine coolant is controlled to flow into the intercooler through the heating passage so as to use the engine coolant to heat the air-fuel mixture in the intercooler. Based on the current intercooled air-fuel mixture temperature, a target ignition angle corresponding to the current intercooled air-fuel mixture temperature is determined from the preset mapping relationship between the intercooled air-fuel mixture temperature and the ignition angle; Based on the target ignition angle, the ignition device is controlled to perform an ignition action.

[0006] In some embodiments, determining the target ignition angle corresponding to the current intercooled mixture temperature from a preset mapping relationship between the intercooled mixture temperature and the ignition angle, based on the current intercooled mixture temperature, includes: Obtain the reference ignition angle corresponding to the engine's current speed and current load; Based on the current intercooler mixture temperature, determine the target ignition angle correction value; The sum of the reference ignition angle and the target ignition angle correction value is determined as the target ignition angle.

[0007] In some implementations, determining the target ignition angle correction value based on the current intercooler mixture temperature includes: Obtain the correspondence table between preset temperature ranges and ignition angle correction values; Determine the target ignition angle correction value corresponding to the temperature range to which the current intercooled air-fuel mixture temperature belongs from the correspondence table; When the current intercooled air-fuel mixture temperature falls between two adjacent preset temperature points in the temperature range, the ignition angle correction value corresponding to the two adjacent preset temperature points is interpolated to obtain the target ignition angle correction value.

[0008] In some implementations, it also includes: When the current intercooled gas mixture temperature is greater than or equal to the preset temperature threshold, the heating path is controlled to stop heating the gas mixture in the intercooler, and the intercooler is controlled to cool the gas mixture.

[0009] In some embodiments, the engine further includes an intake manifold, and controlling the intercooler to cool the air-fuel mixture includes: The current air-fuel mixture temperature in the intake manifold is obtained, wherein the current air-fuel mixture temperature is the temperature of the air-fuel mixture entering the intake manifold after passing through the intercooler; Based on the current mixture temperature, a target duty cycle corresponding to the current mixture temperature is determined from the mapping relationship between the mixture temperature and the duty cycle; The intercooler is controlled to cool the gas mixture according to the target duty cycle.

[0010] In some embodiments, the engine further includes an intake manifold, cylinders, and an electrically variable valve timing system, and also includes: The intake valve throat temperature is obtained, wherein the intake valve throat temperature is the temperature of the air-fuel mixture after it leaves the intercooler and flows through the intake manifold and before it enters the cylinder; The current intake volume entering the cylinder is calculated based on the intake pressure, intake volume, intake valve throat temperature, and volumetric efficiency. Based on the current intake air volume, the electric variable valve timing system is controlled to adjust the valve timing.

[0011] In some implementations, it also includes: When the current intercooled air-fuel mixture temperature drops from greater than or equal to the preset temperature threshold to less than the preset temperature threshold, the step of controlling the engine coolant to flow into the intercooler through the heating passage is re-executed.

[0012] Secondly, this application proposes an engine combustion control device applied to an engine, the engine including an intercooler, an ignition device, and a heating passage for introducing engine coolant into the intercooler, the device comprising: A temperature acquisition unit is used to acquire the current temperature of the intercooled mixture at the outlet of the intercooler. A heating control unit is used to control the engine coolant to flow into the intercooler through the heating passage when the current intercooled air-fuel mixture temperature is less than a preset temperature threshold, so as to use the engine coolant to heat the air-fuel mixture in the intercooler. The ignition angle determination unit is used to determine the target ignition angle corresponding to the current intercooler mixture temperature from a preset mapping relationship between the intercooler mixture temperature and the ignition angle, based on the current intercooler mixture temperature. The ignition execution unit is used to control the ignition device to perform the ignition action based on the target ignition angle.

[0013] 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 combustion control method of any one of the first aspects.

[0014] Fourthly, this application also proposes a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the engine combustion control method of any one of the first aspects.

[0015] In summary, the engine combustion control method provided in this application, by acquiring the current intercooled air-fuel mixture temperature at the intercooler outlet, reflects the thermal state of the mixture before entering the cylinder, and is used to determine whether heating is needed and how to adjust the ignition angle. When the intercooled air-fuel mixture temperature is detected to be lower than a preset temperature threshold, the mixture temperature is too low. At this time, the engine coolant is controlled to flow into the intercooler through the heating passage, using the engine coolant to heat the mixture in the intercooler. This heating action rapidly increases the mixture temperature, improves the atomization and evaporation characteristics of fuel in low-temperature environments, increases the flame propagation speed, and avoids combustion instability or misfire caused by an overly cold mixture. Based on the current intercooled air-fuel mixture temperature, the corresponding target ignition angle is determined from the preset mapping relationship between the intercooled air-fuel mixture temperature and the ignition angle. Since the combustion rate of low-temperature mixtures is slow, the target ignition angle matching the current temperature is obtained through the pre-calibrated mapping relationship, so that the ignition timing is adjusted with the mixture temperature, avoiding afterburning or decreased thermal efficiency due to delayed ignition, and also preventing knocking tendency caused by premature ignition. Based on the target ignition angle, the ignition device is controlled to perform the ignition action, ensuring that the actual ignition angle adapts to the current thermal state of the air-fuel mixture. This allows the mixture to burn at the optimal ignition moment while being heated, guaranteeing combustion stability under low-temperature conditions and improving engine thermal efficiency. This application solves the combustion degradation problem caused by excessively low air-fuel mixture temperature in low-temperature environments through temperature-triggered heating and adaptive ignition angle adjustment. It achieves efficient and stable combustion across the entire temperature range without complex hardware modifications. Attached Figure Description

[0016] 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 This is a schematic flowchart of an engine combustion control method provided in an embodiment of this application; Figure 2 This is a schematic diagram of the structure of an engine combustion control device provided in an embodiment of this application; Figure 3 This is a schematic diagram of an engine combustion control electronic device provided in an embodiment of this application. Detailed Implementation

[0017] 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 orders other than those illustrated or described herein. Furthermore, "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that includes 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.

[0018] This application relates to the field of engine combustion control technology, and is particularly applicable to hybrid powertrain engines equipped with turbocharged intercooling systems. In existing technologies, to suppress knocking and increase intake air density, the turbocharged air-fuel mixture is typically cooled by an intercooler. However, in low-temperature environments, during cold starts, or during warm-up, the intercooler can cause excessive cooling of the air-fuel mixture, leading to poor fuel atomization, difficulty in evaporation, a significant decrease in flame propagation rate, and even misfires or fluctuations in the combustion cycle, resulting in reduced engine thermal efficiency and worsened emissions. The application scenarios of this application include, but are not limited to, cold start conditions in winter when the ambient temperature is below 0°C, the warm-up phase when the engine coolant temperature has not reached the normal range, and any operating conditions in high-altitude and cold regions where combustion instability is caused by excessively low intake air temperature. This application aims to solve the combustion stability problem caused by excessive cooling of the air-fuel mixture under the aforementioned low-temperature conditions.

[0019] Vehicles equipped with hybrid-specific engines typically have the following standard features: First, they are equipped with a full-temperature-range high-efficiency exhaust gas recirculation system, which can achieve stable and reliable exhaust gas recirculation in both low and high temperature environments; second, they adopt an electric variable valve timing mechanism, whose adjustment speed can be 5 to 10 times that of traditional hydraulic variable valve timing mechanisms, providing more direct power response without lag, and control accuracy of 0.5° crankshaft angle, which is superior to the accuracy level of ±2° typically achieved by hydraulic mechanisms; in addition, they are matched with high-energy ignition coils with ignition energy greater than 120mJ to ensure reliable ignition of the air-fuel mixture under various operating conditions.

[0020] To more clearly illustrate the technical solution of this application, the following specific terms are explained in this application.

[0021] The intercooler in this application refers to a heat exchange device installed between the compressor outlet of the turbocharger and the intake manifold, used to regulate the temperature of the pressurized mixture.

[0022] The ignition device in this application refers to a component used to generate an electric spark to ignite the combustible mixture in the cylinder, which typically includes an ignition coil and a spark plug.

[0023] The heating passage in this application refers to an independent flow channel that introduces engine coolant from the engine body into the intercooler. A solenoid valve can be installed on this passage to control the coolant flow rate.

[0024] The engine coolant in this application refers to the antifreeze used to absorb heat from the cylinder block and circulate during engine operation. Its temperature can rise to over 80°C during normal engine operation, thus it can serve as a heat source for low-temperature air-fuel mixture.

[0025] The intercooled air-fuel mixture temperature in this application refers to the temperature of the air-fuel mixture flowing out of the intercooler outlet. This temperature reflects the thermal state of the air-fuel mixture before it enters the intake manifold after heat exchange in the intercooler. It is an input parameter that determines whether to start heating and how to correct the ignition angle.

[0026] The preset temperature threshold in this application refers to a pre-calibrated critical temperature value (e.g., 40°C). When the temperature of the intercooled air-fuel mixture is lower than this threshold, it is determined that the mixture is too cold and heating needs to be started. When it is higher than or equal to this threshold, heating is not required or the mode is switched to cooling. The actual calibration value is adjusted according to different engine models.

[0027] The preset mapping relationship in this application refers to the correspondence between the intercooled mixture temperature and the ignition angle correction value, which is pre-calibrated through bench testing. This relationship is stored in the engine controller in tabular form, and the ignition angle correction amount at any temperature can be obtained by interpolation calculation.

[0028] The target ignition angle in this application refers to the crankshaft rotation angle used to control the ignition device to perform ignition. It is obtained by superimposing the reference ignition angle with the correction value obtained based on the current intercooled air-fuel mixture temperature, and aims to match the ignition timing with the actual combustion rate of the air-fuel mixture.

[0029] In this application, the intake manifold refers to the piping assembly that distributes the air-fuel mixture from the throttle valve to each cylinder.

[0030] The intake valve throat temperature in this application refers to the temperature of the mixed airflow near the intake valve head. This temperature is closer to the actual intake air temperature inside the cylinder than the intercooler outlet temperature and is used to calculate the intake volume.

[0031] The electric variable valve timing system in this application refers to a mechanism that uses a motor to quickly adjust the opening and closing times of the valves, and its response speed and accuracy are superior to those of the traditional hydraulic VVT.

[0032] Please see Figure 1This is a schematic flowchart of an engine combustion control method provided in an embodiment of this application. The method is applied to an engine, which includes an intercooler, an ignition device, and a heating passage for introducing engine coolant into the intercooler. Specifically, it may include: S110, Obtain the current intercooled mixture temperature at the intercooler outlet; For example, the air-fuel mixture temperature at the intercooler outlet reflects the thermal state of the air-fuel mixture before it enters the engine cylinder after heat exchange in the intercooler. The temperature directly affects the fuel atomization quality and flame propagation speed. The temperature value is collected by a temperature sensor to determine whether the air-fuel mixture needs to be heated and how to adjust the ignition timing.

[0033] S120. When the current intercooled air-fuel mixture temperature is lower than the preset temperature threshold, control the engine coolant to flow into the intercooler through the heating passage so as to use the engine coolant to heat the air-fuel mixture in the intercooler. For example, during normal engine operation, the coolant temperature gradually increases. Introducing the high-temperature coolant into the intercooler utilizes the heat carried by the coolant to raise the temperature of the low-temperature air-fuel mixture, bringing the air-fuel mixture temperature back to a range conducive to atomization and combustion. This improves combustion conditions under low-temperature conditions and avoids slow combustion caused by an overly cold air-fuel mixture.

[0034] S130. Based on the current intercooled air-fuel mixture temperature, determine the target ignition angle corresponding to the current intercooled air-fuel mixture temperature from the preset mapping relationship between the intercooled air-fuel mixture temperature and the ignition angle. For example, since changes in the temperature of the air-fuel mixture will alter the combustion rate, the combustion rate is slower at lower temperatures, requiring an appropriate increase in the ignition advance angle to compensate for the combustion delay. Conversely, when the temperature rises, the ignition advance angle needs to be reduced to prevent knocking. Through a pre-calibrated mapping relationship, the matching ignition angle is found based on the current intercooled air-fuel mixture temperature, enabling the ignition timing to adaptively follow changes in the thermal state of the air-fuel mixture.

[0035] S140. Based on the target ignition angle, control the ignition device to perform the ignition action.

[0036] For example, the determined target ignition angle is used as the actual ignition time, and the ignition coil is controlled to generate an electric spark to ignite the air-fuel mixture in the cylinder, so that the ignition time falls on the optimal combustion phase corresponding to the current air-fuel mixture temperature. Thus, the air-fuel mixture is heated while combustion is completed at the optimal ignition angle, ensuring stable combustion and high thermal efficiency under low temperature conditions.

[0037] In summary, the engine combustion control method provided in this application, by acquiring the current intercooled air-fuel mixture temperature at the intercooler outlet, reflects the thermal state of the mixture before entering the cylinder, and is used to determine whether heating is needed and how to adjust the ignition angle. When the intercooled air-fuel mixture temperature is detected to be lower than a preset temperature threshold, the mixture temperature is too low. At this time, the engine coolant is controlled to flow into the intercooler through the heating passage, and the engine coolant is used to heat the mixture in the intercooler. This heating action rapidly increases the mixture temperature, improves the atomization and evaporation characteristics of fuel in low-temperature environments, increases the flame propagation speed, and avoids combustion instability or misfire caused by excessively cold mixture. Based on the current intercooled air-fuel mixture temperature, the corresponding target ignition angle is determined from the preset mapping relationship between the intercooled air-fuel mixture temperature and the ignition angle. Since the combustion rate of low-temperature mixtures is slow, the target ignition angle matching the current temperature is obtained through the pre-calibrated mapping relationship, so that the ignition timing is adjusted with the mixture temperature, avoiding afterburning or decreased thermal efficiency due to delayed ignition, and also preventing knocking tendency caused by premature ignition. Based on the target ignition angle, the ignition device is controlled to perform the ignition action, ensuring that the actual ignition angle adapts to the current thermal state of the air-fuel mixture. This allows the mixture to burn at the optimal ignition moment while being heated, guaranteeing combustion stability under low-temperature conditions and improving engine thermal efficiency. This application solves the combustion degradation problem caused by excessively low air-fuel mixture temperature in low-temperature environments through temperature-triggered heating and adaptive ignition angle adjustment. It achieves efficient and stable combustion across the entire temperature range without complex hardware modifications.

[0038] The engine combustion control system disclosed in this application includes an engine, a turbocharger, an intercooler, an intake manifold, an ignition system, an electrically variable valve timing system, and a heating passage. The turbocharger compressor outlet is connected to the intercooler inlet, and the intercooler outlet is connected to the intake manifold, which is connected to the cylinders via intake valves. One end of the heating passage is connected to the engine coolant circulation loop, and the other end is connected to the interior of the intercooler. A solenoid valve is installed on this passage to control the coolant flow rate. The ignition coil of the ignition system is connected to the spark plug and mounted on the cylinder head. The electrically variable valve timing system is coupled to the intake valve camshaft to adjust the valve opening timing. Furthermore, temperature sensors are installed at the intercooler outlet and inside the intake manifold to collect the air-fuel mixture temperature. The intercooler itself is also equipped with an actuator for adjusting the cooling intensity. These structures work together to achieve active adjustment of the air-fuel mixture temperature, adaptive correction of the ignition angle, and control of the intake air volume.

[0039] In some instances, based on the current intercooled air-fuel mixture temperature, a target ignition angle corresponding to the current intercooled air-fuel mixture temperature is determined from a preset mapping relationship between the intercooled air-fuel mixture temperature and the ignition angle, including: Obtain the reference ignition angle corresponding to the engine's current speed and current load; Based on the current intercooled air-fuel mixture temperature, determine the target ignition angle correction value; The sum of the reference ignition angle and the target ignition angle correction value is determined as the target ignition angle.

[0040] For example, the engine controller determines the current engine speed and load based on signals collected by the crankshaft position sensor and the air flow meter or intake pressure sensor. Engine speed and load are operating parameters that determine the engine's basic ignition advance angle. The controller pre-stores a reference ignition angle pulse map obtained through bench calibration tests. This pulse map uses engine speed and load as two-dimensional coordinate axes, with each coordinate point corresponding to a basic ignition angle that allows the engine to achieve optimal combustion efficiency under that operating condition. The controller takes the acquired current engine speed and load as input and extracts the reference ignition angle corresponding to the current operating condition from the pulse map through table lookup or interpolation calculation. This reference ignition angle represents the ignition timing that optimizes engine thermal efficiency under standard intake air temperature conditions.

[0041] Because the temperature of the intercooled air-fuel mixture deviates from the standard calibration temperature, it alters the flame propagation rate of the mixture within the cylinder. Lower temperatures result in slower combustion, necessitating an increase in the ignition advance angle to compensate for the combustion delay; conversely, higher temperatures require a decrease in the ignition advance angle. The controller internally stores a preset mapping relationship between the intercooled air-fuel mixture temperature and the ignition angle correction value. This mapping relationship is typically represented as a calibration table with the temperature point on the x-axis and the correction value on the y-axis. The controller uses the collected current intercooled air-fuel mixture temperature as a lookup index to determine the corresponding target ignition angle correction value from this preset mapping relationship. This correction value can be positive or negative; a positive value represents increasing the ignition advance angle, and a negative value represents decreasing it. The reference ignition angle and the target ignition angle correction value are summed, and the sum is determined as the target ignition angle used to execute the ignition action.

[0042] In summary, this application's embodiments ensure that the base value of the ignition angle matches the engine's basic operating state by obtaining a reference ignition angle corresponding to the engine's current speed and load, avoiding unreasonable ignition angle selection due to ignoring speed and load differences. The target ignition angle correction value is determined based on the current intercooled air-fuel mixture temperature, allowing the ignition angle adjustment to directly respond to changes in the mixture's thermal state. Since flame propagation speed slows down at low temperatures, increasing the ignition advance angle compensates for combustion delay, ensuring the cylinder pressure peak occurs at the optimal crankshaft angle, thereby improving expansion efficiency. Conversely, reducing the ignition advance angle at higher air-fuel mixture temperatures effectively suppresses knocking tendencies and protects the engine from abnormal combustion damage. Summing the reference ignition angle and the correction value yields the target ignition angle, achieving ignition angle control across different operating conditions. This retains the basic calibration based on speed and load while introducing correction based on intake air temperature, ensuring the ignition timing matches the actual combustion rate of the air-fuel mixture across the entire temperature range. While improving atomization through low-temperature heating, further optimization of the ignition angle enhances combustion isochoricity, reduces cycle fluctuations, and improves engine thermal efficiency.

[0043] In some instances, the target ignition angle correction value is determined based on the current intercooler mixture temperature, including: Obtain the correspondence table between preset temperature ranges and ignition angle correction values; Determine the target ignition angle correction value corresponding to the temperature range to which the current intercooler mixture temperature belongs from the correspondence table; When the current intercooled air-fuel mixture temperature falls between two adjacent preset temperature points in the temperature range, the ignition angle correction value corresponding to the two adjacent preset temperature points is interpolated to obtain the target ignition angle correction value.

[0044] For example, the engine controller has a pre-stored table of the correspondence between preset temperature ranges and ignition angle correction values, as shown in Table 1.

[0045] Table 1 Relationship between temperature and ignition angle correction values

[0046] This correspondence table uses discrete temperature points as the x-axis, with each temperature point corresponding to an ignition angle correction value. For example, in the table, 40℃ corresponds to a correction value of 0°, 30℃ to 1°, 20℃ to 2°, 10℃ to 3°, and 0℃ to 4°. After acquiring this correspondence table, the controller compares the collected current intercooler mixture temperature with the preset temperature points in the table to determine the temperature range to which the current intercooler mixture temperature belongs. Then, it extracts the ignition angle correction value corresponding to that temperature range from the table as the target ignition angle correction value. If the current intercooler mixture temperature is exactly equal to a preset temperature point in the table, the correction value corresponding to that preset temperature point is directly determined as the target ignition angle correction value.

[0047] When the current intercooled air-fuel mixture temperature falls between two adjacent preset temperature points in the corresponding relationship table, the controller performs linear interpolation calculations on the ignition angle correction values ​​corresponding to those two adjacent preset temperature points to obtain the target ignition angle correction value corresponding to the current intercooled air-fuel mixture temperature. For example, in the corresponding relationship table, 30℃ corresponds to a correction value of 1°, and 20℃ corresponds to a correction value of 2°. If the current intercooled air-fuel mixture temperature is 25℃, it falls between 20℃ and 30℃. The controller calculates the correction value according to the temperature difference ratio, that is, from 20℃ to 30℃, a 10℃ increase in temperature increases the correction value by 1°, and 25℃ is 5℃ higher than 20℃, so the correction value increases by 0.5° on top of 2°, resulting in a target ignition angle correction value of 1.5°. The interpolation calculation ensures that the ignition angle correction value changes continuously with the intercooled air-fuel mixture temperature, avoiding abrupt changes in the correction value caused by temperature point discreteness.

[0048] In summary, this application establishes a mapping between the intercooled mixture temperature and the ignition advance angle compensation amount through a preset temperature range and ignition angle correction value correspondence table. A larger ignition angle correction value corresponds to a lower intercooled mixture temperature, increasing the ignition advance angle to compensate for the decrease in combustion rate caused by low temperature. When the intercooled mixture temperature approaches a preset temperature threshold, the correction value approaches zero, preventing excessive ignition advance that could lead to knocking. When the temperature falls between two adjacent preset temperature points, interpolation is used to ensure a smooth transition of the target ignition angle correction value with temperature changes, avoiding jumps in ignition timing due to abrupt changes in the correction value, thereby maintaining the stability of the combustion process. This correspondence table can be updated through bench calibration according to different engine models and fuel characteristics, ensuring that the control parameters match the specific engine hardware. This allows the ignition angle correction value to be compensated for under any intercooled mixture temperature, improving the control accuracy of the ignition angle and enhancing combustion efficiency under low-temperature conditions.

[0049] In some instances, it also includes: When the current temperature of the intercooled air-fuel mixture is greater than or equal to the preset temperature threshold, the heating circuit is controlled to stop heating the air-fuel mixture in the intercooler, and the intercooler is controlled to cool the air-fuel mixture.

[0050] For example, when the current intercooled air-fuel mixture temperature is greater than or equal to a preset temperature threshold, the air-fuel mixture temperature at the intercooler outlet is already at a normal or slightly high level. At this point, the air-fuel mixture can achieve good atomization and evaporation characteristics without additional heating. If the engine coolant is used to continue heating the air-fuel mixture, it will lead to excessively high intake air temperature, increase the tendency to knock, reduce intake air density, and weaken the engine's thermal efficiency. Therefore, the controller controls the solenoid valve in the heating path to close, cutting off the flow of engine coolant to the intercooler, thus stopping the heating of the air-fuel mixture. At the same time, the controller also controls the intercooler to resume its normal cooling function, initiating a cooling action on the air-fuel mixture. For example, it allows the cooling medium to flow through the intercooler's cooling channels, reducing the temperature of the pressurized air-fuel mixture to a suitable range to suppress knock and improve charging efficiency, ensuring stable and efficient engine operation under normal or high-temperature conditions.

[0051] In summary, this embodiment of the application achieves automatic switching between heating and cooling modes by setting a preset temperature threshold as a switching point. When the temperature of the intercooled air-fuel mixture is below the threshold, heating is activated to improve low-temperature combustion; when the temperature of the intercooled air-fuel mixture is above or equal to the threshold, heating is deactivated and cooling is activated to avoid overheating, ensuring that the air-fuel mixture temperature is always regulated within a window range favorable for combustion. This process prevents combustion instability and decreased thermal efficiency caused by overcooling of the air-fuel mixture at low temperatures, while also avoiding the risk of knocking and loss of charging efficiency caused by overheating at high temperatures, maintaining the engine's combustion stability and thermal efficiency across the entire temperature range.

[0052] In some instances, the engine also includes an intake manifold that controls the intercooler to cool the air-fuel mixture, including: Get the current air-fuel mixture temperature in the intake manifold, where the current air-fuel mixture temperature is the temperature of the air-fuel mixture entering the intake manifold after passing through the intercooler; Based on the current mixture temperature, the target duty cycle corresponding to the current mixture temperature is determined from the mapping relationship between the mixture temperature and the duty cycle; The intercooler is controlled to cool the air-fuel mixture based on the target duty cycle.

[0053] For example, the engine also includes an intake manifold. During the process of controlling the intercooler to cool the air-fuel mixture, the current air-fuel mixture temperature inside the intake manifold is obtained. This current air-fuel mixture temperature is the temperature value of the air-fuel mixture after leaving the intercooler outlet and flowing into the intake manifold. As a distribution chamber for the air-fuel mixture before it enters each cylinder, the air-fuel mixture temperature inside the intake manifold is closer to the actual thermal state when it enters the cylinder than the temperature at the intercooler outlet. This avoids control deviations caused by heat exchange in the pipeline or environmental heat dissipation when cooling control is based solely on the intercooler outlet temperature.

[0054] Based on the obtained current air-fuel mixture temperature, the target duty cycle corresponding to the current air-fuel mixture temperature is determined from the pre-calibrated mapping relationship between air-fuel mixture temperature and duty cycle. This mapping relationship is pre-calibrated through bench testing and stored in the engine controller's memory. The mapping relationship characterizes the one-to-one correspondence between the intake manifold temperature value and the duty cycle of the intercooler cooling actuator drive signal. When the current air-fuel mixture temperature is high, the mapping relationship gives a larger duty cycle value to enhance the cooling intensity. When the current air-fuel mixture temperature is close to the target range, the mapping relationship gives a smaller duty cycle to weaken or maintain the cooling. The controller uses the current air-fuel mixture temperature as a lookup index and extracts the corresponding target duty cycle value from the mapping relationship by looking up a table or interpolation calculation.

[0055] Based on the determined target duty cycle, the controller outputs a control signal with the corresponding duty cycle to drive the intercooler to perform cooling action. The intercooler adjusts the flow rate of its internal cooling medium or the speed of its cooling fan according to the received duty cycle signal. The larger the duty cycle, the higher the proportion of the cooling actuator opening time, the more heat the intercooler absorbs from the air-fuel mixture flowing through it, and the greater the cooling effect of the air-fuel mixture. Conversely, the smaller the duty cycle, the smaller the cooling effect, so that the temperature of the air-fuel mixture in the intake manifold is maintained within a reasonable range that is conducive to suppressing knock and maintaining a high intake density, thereby achieving control of the intercooler's cooling intensity.

[0056] In summary, this embodiment of the application, by obtaining the current air-fuel mixture temperature in the intake manifold, more accurately reflects the true thermal state of the air-fuel mixture before entering the cylinder than directly using the intercooler outlet temperature. This avoids measurement deviations caused by heat exchange between the intercooler and the intake manifold, thus improving the accuracy of cooling control. Based on the current air-fuel mixture temperature, a target duty cycle is determined from a preset mapping relationship, establishing a quantitative correspondence between temperature and cooling intensity, avoiding response lag or overcooling caused by fuzzy control. The intercooler is controlled to perform cooling actions according to the target duty cycle, converting the temperature signal into quantifiable actuator drive parameters. This achieves continuous control of the air-fuel mixture cooling amplitude, preventing the risk of knocking due to insufficient cooling and avoiding the decrease in intake air density and combustion deterioration caused by overcooling, thereby maintaining the engine's combustion stability and thermal efficiency under all operating conditions.

[0057] In some instances, the engine also includes an intake manifold, cylinders, and an electrically variable valve timing system, and also includes: The intake valve throat temperature is obtained, which is the temperature of the air-fuel mixture after it leaves the intercooler and flows through the intake manifold before entering the cylinder. Calculate the current intake volume into the cylinder based on intake pressure, intake volume, intake valve throat temperature, and volumetric efficiency. Based on the current intake air volume, the electric variable valve timing system is controlled to adjust the valve timing.

[0058] For example, the intake valve throat temperature is the temperature of the air-fuel mixture after it leaves the intercooler and flows through the intake manifold but before entering the cylinder. It is collected by a temperature sensor located near the intake valve or at the intake valve seat. As the air-fuel mixture flows through the intake manifold, it absorbs heat from the manifold walls and heat transferred by the engine through thermal conduction. Therefore, the intake valve throat temperature is usually higher than the intercooler outlet temperature. Using the intake valve throat temperature as a temperature parameter for calculating the intake volume is closer to the actual thermal state of the air-fuel mixture when it enters the cylinder than directly using the intercooler outlet temperature or the intake manifold temperature.

[0059] The current intake air volume entering the cylinder is calculated based on the intake pressure, intake volume, intake valve throat temperature, and volumetric efficiency. Specifically, the calculation is performed using a modified form of the ideal gas law, with the formula: m = P × V / (R × T). port )×VE, where m represents the current intake air volume, P is the intake manifold pressure measured by the intake pressure sensor, reflecting the density of gas molecules per unit volume, V is the intake volume, determined by the engine displacement or single-cylinder working volume, and is a fixed parameter of the engine's mechanical structure, R is the gas constant, determined by the physical properties of air, and T port The intake valve throat temperature obtained in the above steps is used to correct for the effect of gas density changes with temperature. VE is the volumetric efficiency, representing the ratio of the actual air mass entering the cylinder to the theoretical maximum intake mass. This volumetric efficiency is pre-calibrated through bench testing and stored in the characteristic spectrum of the engine controller, and is adjusted according to engine speed and load changes. The controller uses intake pressure P, intake volume V, gas constant R, and intake valve throat temperature T. port Substituting the volumetric efficiency VE into the above formula, first calculate the air-fuel mixture density, then multiply this density by the intake volume V and the volumetric efficiency VE to obtain the actual intake volume m entering the cylinder.

[0060] Based on the current intake air volume, the electric variable valve timing system adjusts the valve timing. Driven by an electric motor, the system adjusts the opening and closing times of the intake valves, offering superior response speed and adjustment accuracy compared to traditional hydraulic variable valve timing systems. The controller pre-stores target valve timing maps for different engine speeds and loads. These maps provide target values ​​for the intake valve opening and closing angles to achieve optimal engine thermal efficiency; however, these target values ​​are calibrated based on standard intake air temperatures. Since changes in intake valve throat temperature alter intake air density, causing the actual intake air volume to deviate from the target volume, controlling the valve timing according to the target map will not guarantee the desired air-fuel mixture charge in the cylinder. The controller compares the calculated current intake volume with the target intake volume corresponding to the current speed and load. Based on the deviation between the two, it determines the adjustment direction and adjustment range of valve timing and outputs a control signal to the actuator of the electric variable valve timing system. This drives the intake valve camshaft to rotate a certain angle earlier or later relative to the crankshaft, changing the opening and closing times of the intake valves. This alters the actual intake volume entering the cylinder, matching the engine's actual intake state with the target requirements under the current speed and load, thereby ensuring combustion stability and improving thermal efficiency.

[0061] In summary, this embodiment uses the intake valve throat temperature as a temperature parameter for calculating the intake volume. This temperature is closer to the actual thermal state of the air-fuel mixture entering the cylinder than the intercooler outlet temperature or intake manifold temperature, avoiding temperature measurement deviations caused by pipeline heat exchange or environmental heat dissipation. This makes the intake density correction more accurate, and the calculated current intake volume better reflects the actual air quality entering the cylinder. Calculating the current intake volume based on intake pressure, intake volume, intake valve throat temperature, and volumetric efficiency avoids control errors caused by relying on empirical values. The electric variable valve timing system adjusts the valve timing according to the calculated current intake volume, using the intake volume parameter as the basis for VVT adjustment. This allows the valve timing to respond to intake density fluctuations caused by changes in intake valve throat temperature, automatically adjusting the intake valve opening and closing times to compensate for intake volume deviations. This ensures that the cylinder always receives an air-fuel mixture charge matching the current speed and load, maintaining air-fuel ratio control across the entire temperature range and improving engine thermal efficiency.

[0062] In some instances, it also includes: When the current intercooled air-fuel mixture temperature drops from above or equal to a preset temperature threshold to below a preset temperature threshold, the step of controlling the flow of engine coolant into the intercooler through the heating passage is re-executed.

[0063] For example, during normal engine operation, the intercooled air-fuel mixture temperature may change due to fluctuations in ambient temperature, changes in engine load, or changes in vehicle driving conditions. Previously, the intercooled air-fuel mixture temperature was above or equal to a preset temperature threshold. The heating passage was closed, and the intercooler was performing its cooling function, maintaining the mixture temperature at a normal or slightly high level. However, if due to a sudden drop in ambient temperature, a decrease in boost pressure caused by the engine entering low-load operation, or a reduction in intake air volume due to driving on a long downhill section, the mixture temperature at the intercooler outlet gradually decreases until it falls below the preset temperature threshold. At this point, the mixture temperature has fallen into a low-temperature range unfavorable for atomization and combustion. The controller monitors the intercooled air-fuel mixture temperature. Once it detects that the temperature has crossed from above or equal to the preset temperature threshold to below the preset temperature threshold, it immediately re-executes the step of controlling the flow of engine coolant into the intercooler through the heating passage. That is, it reopens the heating passage solenoid valve, allowing the high-temperature engine coolant to flow through the intercooler again to heat the low-temperature mixture, while simultaneously stopping the intercooler's cooling function.

[0064] In summary, the control logic of this application avoids control oscillations caused by repeated start-stop of the heating path when the temperature fluctuates frequently near the preset temperature threshold. It ensures that heating is restored in time when the temperature of the air-fuel mixture drops back to the low temperature range, maintaining the temperature of the air-fuel mixture within a range conducive to combustion, thereby continuously ensuring the combustion stability and thermal efficiency of the engine under all operating conditions.

[0065] Please see Figure 2 This is a schematic diagram of an engine combustion control device provided in an embodiment of this application. The device is applied to an engine, which includes an intercooler, an ignition device, and a heating passage for introducing engine coolant into the intercooler. Temperature acquisition unit 21 is used to acquire the current temperature of the intercooled mixture at the outlet of the intercooler; The heating control unit 22 is used to control the engine coolant to flow into the intercooler through the heating passage when the current intercooled air-fuel mixture temperature is less than a preset temperature threshold, so as to use the engine coolant to heat the air-fuel mixture in the intercooler. Ignition angle determination unit 23 is used to determine the target ignition angle corresponding to the current intercooled mixture temperature from the preset mapping relationship between the intercooled mixture temperature and the ignition angle based on the current intercooled mixture temperature; The ignition execution unit 24 is used to control the ignition device to perform ignition actions based on the target ignition angle.

[0066] Please see Figure 3This 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 combustion control method.

[0067] Since the electronic device described in this embodiment is the device used to implement the engine combustion control device in the embodiments 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 embodiments of this application. Therefore, how the electronic device implements the method in the embodiments 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 embodiments of this application falls within the scope of protection of this application.

[0068] In practice, when the computer program 311 is executed by the processor, it can implement any of the embodiments corresponding to the first aspect.

[0069] 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.

[0070] 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.

[0071] 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, as well as 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. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0072] 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.

[0073] 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.

[0074] 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 an engine combustion control method in the corresponding embodiment.

[0075] 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.

[0076] 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.

[0077] 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; for instance, 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.

[0078] 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.

[0079] 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.

[0080] 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.

[0081] 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.

[0082] Although preferred embodiments have been described in this specification, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications beyond the scope of this specification.

[0083] 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. An engine combustion control method, characterized in that, Applied to an engine, the engine including an intercooler, an ignition device, and a heating passage for introducing engine coolant into the intercooler, the method includes: Obtain the current intercooled mixture temperature at the outlet of the intercooler; When the current intercooled air-fuel mixture temperature is lower than a preset temperature threshold, the engine coolant is controlled to flow into the intercooler through the heating passage, so as to use the engine coolant to heat the air-fuel mixture in the intercooler; Based on the current intercooled air-fuel mixture temperature, a target ignition angle corresponding to the current intercooled air-fuel mixture temperature is determined from the preset mapping relationship between the intercooled air-fuel mixture temperature and the ignition angle; Based on the target ignition angle, the ignition device is controlled to perform an ignition action.

2. The method according to claim 1, characterized in that, The step of determining the target ignition angle corresponding to the current intercooled mixture temperature from a preset mapping relationship between the intercooled mixture temperature and the ignition angle, based on the current intercooled mixture temperature, includes: Obtain the reference ignition angle corresponding to the engine's current speed and current load; Based on the current intercooler mixture temperature, determine the target ignition angle correction value; The sum of the reference ignition angle and the target ignition angle correction value is determined as the target ignition angle.

3. The method according to claim 2, characterized in that, The determination of the target ignition angle correction value based on the current intercooled air-fuel mixture temperature includes: Obtain the correspondence table between preset temperature ranges and ignition angle correction values; Determine the target ignition angle correction value corresponding to the temperature range to which the current intercooled air-fuel mixture temperature belongs from the correspondence table; When the current intercooled air-fuel mixture temperature falls between two adjacent preset temperature points in the temperature range, the ignition angle correction value corresponding to the two adjacent preset temperature points is interpolated to obtain the target ignition angle correction value.

4. The method according to claim 1, characterized in that, Also includes: When the current intercooled gas mixture temperature is greater than or equal to the preset temperature threshold, the heating path is controlled to stop heating the gas mixture in the intercooler, and the intercooler is controlled to cool the gas mixture.

5. The method according to claim 4, characterized in that, The engine also includes an intake manifold, and controlling the intercooler to cool the air-fuel mixture includes: The current air-fuel mixture temperature in the intake manifold is obtained, wherein the current air-fuel mixture temperature is the temperature of the air-fuel mixture entering the intake manifold after passing through the intercooler; Based on the current mixture temperature, a target duty cycle corresponding to the current mixture temperature is determined from the mapping relationship between the mixture temperature and the duty cycle; The intercooler is controlled to cool the air-fuel mixture according to the target duty cycle.

6. The method according to claim 1, characterized in that, The engine also includes an intake manifold, cylinders, and an electrically variable valve timing system, and further includes: The intake valve throat temperature is obtained, wherein the intake valve throat temperature is the temperature of the air-fuel mixture after it leaves the intercooler and flows through the intake manifold and before it enters the cylinder; The current intake volume entering the cylinder is calculated based on the intake pressure, intake volume, intake valve throat temperature, and volumetric efficiency. Based on the current intake air volume, the electric variable valve timing system is controlled to adjust the valve timing.

7. The method according to claim 1, characterized in that, Also includes: When the current intercooled air-fuel mixture temperature drops from greater than or equal to the preset temperature threshold to less than the preset temperature threshold, the step of controlling the engine coolant to flow into the intercooler through the heating passage is re-executed.

8. An engine combustion control device, characterized in that, Applied to an engine, the engine including an intercooler, an ignition device, and a heating passage for introducing engine coolant into the intercooler, including: A temperature acquisition unit is used to acquire the current temperature of the intercooled mixture at the outlet of the intercooler. A heating control unit is used to control the engine coolant to flow into the intercooler through the heating passage when the current intercooled air-fuel mixture temperature is less than a preset temperature threshold, so as to use the engine coolant to heat the air-fuel mixture in the intercooler. The ignition angle determination unit is used to determine the target ignition angle corresponding to the current intercooling mixture temperature from a preset mapping relationship between the intercooling mixture temperature and the ignition angle, based on the current intercooling mixture temperature. An ignition execution unit is used to control the ignition device to perform an ignition action based on the target ignition angle.

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, when executing the computer program stored in the memory, implements the steps of the engine combustion 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 combustion control method as described in any one of claims 1 to 7.

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