Carbon canister desorption control method, system and vehicle

Abstract

The embodiment of the application discloses a kind of carbon tank desorption control method, system and vehicle, the method comprises: obtaining the altitude of vehicle, ambient temperature and the state of charge SOC of power battery;In the case where at least one of the following is met, the current speed of engine is obtained: the altitude is greater than the first preset threshold;The ambient temperature is greater than the second preset threshold;The SOC is greater than the third preset threshold;According to the corresponding relationship of preset engine speed and correction coefficient, the correction coefficient corresponding to the current speed is determined;Wherein, the correction coefficient is greater than 0 and less than or equal to 1 numerical value;The maximum air path torque request value of the engine is corrected based on the correction coefficient, to obtain the maximum air path torque request value after correction;And based on the maximum air path torque request value after correction control the engine runs, to execute carbon tank desorption.

Description

Technical Field

[0001] This invention relates to the field of vehicle control technology, specifically to a carbon canister desorption control method, system, and vehicle. Background Technology

[0002] The carbon canister is a core component of a car's fuel evaporation control system. It is used to adsorb fuel vapors that evaporate from the fuel tank, preventing them from being directly emitted into the atmosphere and causing environmental pollution. Under normal operating conditions, the vacuum (i.e., intake negative pressure) created in the engine intake manifold draws the fuel vapors adsorbed in the carbon canister into the engine cylinders to participate in combustion, completing the carbon canister desorption process.

[0003] However, when a vehicle is in a low-pressure environment such as at high altitudes, the external atmospheric pressure is significantly reduced, the air is thinner, and the engine's charging efficiency under the same load decreases significantly, making it difficult to establish a sufficient vacuum pressure inside the intake manifold. Under these conditions, the suction power of the intake manifold for fuel vapor in the carbon canister is greatly weakened, easily leading to insufficient carbon canister desorption. If desorption cannot be effective for a long time, the adsorption medium in the carbon canister will tend to be overload saturated, resulting in fuel vapor overflow and excessive vehicle evaporative emissions. At the same time, if the desorption process is not coordinated with the vehicle's current environmental conditions and the energy supply capacity of the energy system, blindly changing the engine's operating state can also have an adverse effect on the overall vehicle performance. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the purpose of this application is to provide a carbon canister desorption control method, system and vehicle that can actively limit the torque of the engine intake air path to reconstruct the high vacuum environment of the intake manifold in low-pressure environments such as high altitude, and achieve efficient, stable and sufficient suction and desorption of fuel vapor in the carbon canister while taking into account the power demand of the whole vehicle and the power supply boundary of the power battery.

[0005] In a first aspect, embodiments of this application provide a carbon canister desorption control method, comprising: acquiring the vehicle's altitude, ambient temperature, and the state of charge (SOC) of the power battery; acquiring the current engine speed under at least one of the following conditions: the altitude is greater than a first preset threshold; the ambient temperature is greater than a second preset threshold; the SOC is greater than a third preset threshold; determining a correction coefficient corresponding to the current engine speed according to a preset correspondence between engine speed and correction coefficient; wherein the correction coefficient is a value greater than 0 and less than or equal to 1; correcting the maximum airflow torque request value of the engine based on the correction coefficient to obtain a corrected maximum airflow torque request value; and controlling the engine operation based on the corrected maximum airflow torque request value to perform carbon canister desorption.

[0006] The carbon canister desorption control method provided in this application adopts an active air path torque limiting control architecture based on multi-dimensional operating condition joint judgment and nonlinear mapping of engine speed. This achieves an upgrade in control mode from "conventional passive reliance on the negative pressure deficiency caused by self-aspirating characteristics" to "actively attenuating the upper limit of air path torque to reconstruct the high vacuum of intake air". This method simultaneously collects altitude, ambient temperature and the state of charge (SOC) of the power battery in the early stage of control, and triggers a desorption enhancement strategy when all three exceed a preset threshold. It accurately locks the specific operating conditions of "low air pressure at high altitude, easy fuel volatility, and sufficient battery power compensation" from the physical source, effectively eliminating unnecessary torque limiting intervention in the normal negative pressure zone, low temperature and low volatility zone or low power zone in plains, ensuring normal driving experience and battery safety. At the same time, by directly multiplying the maximum airway torque request value by the speed-dependent correction coefficient at the engine airway dimension, the engine throttle opening is forcibly reduced. Without adding additional hardware, a strong intake manifold negative pressure environment is artificially created, which greatly improves the suction flow and desorption efficiency of fuel vapor in the carbon canister and effectively limits carbon canister saturation and excessive evaporative emissions.

[0007] In one possible embodiment, determining the correction coefficient corresponding to the current engine speed based on a preset correspondence between engine speed and correction coefficient includes: in response to the current engine speed being in the range of zero to a first engine speed, determining that the correction coefficient monotonically decreases from a first coefficient value to a second coefficient value; in response to the current engine speed being in the range of the first engine speed to the second engine speed, determining that the correction coefficient remains at the second coefficient value; in response to the current engine speed being in the range of the second engine speed to the third engine speed, determining that the correction coefficient monotonically increases from the second coefficient value to a third coefficient value; in response to the current engine speed being in the range of the third engine speed to the fourth engine speed, determining that the correction coefficient remains at the third coefficient value; in response to the current engine speed being in the range of the fourth engine speed to the fifth engine speed, determining that the correction coefficient monotonically decreases from the third coefficient value to the fourth coefficient value; and in response to the current engine speed being in the range of the fifth engine speed to the sixth engine speed, determining that the correction coefficient remains at the fourth coefficient value; wherein the first coefficient value is greater than the third coefficient value, the third coefficient value is greater than the second coefficient value, and the second coefficient value is greater than the fourth coefficient value.

[0008] In this implementation, a differentiated multi-stage torque reduction configuration mechanism based on speed characteristics is used. A small correction coefficient is configured in the commonly used cruising range at low and medium speeds to deeply reduce the intake pressure and enhance desorption. In the transition acceleration range, the upper limit of torque is appropriately increased to take into account the power response. This achieves fine decoupling control of desorption efficiency and power characteristics across the entire speed range.

[0009] In one possible embodiment, the first rotational speed is 1000 rpm, the second rotational speed is 2400 rpm, the third rotational speed is 2500 rpm, the fourth rotational speed is 4400 rpm, the fifth rotational speed is 4500 rpm, and the sixth rotational speed is 5500 rpm; the first coefficient value is 1.0, the second coefficient value is 0.7, the third coefficient value is 0.8, and the fourth coefficient value is 0.6.

[0010] In this implementation, by precisely configuring specific speed cutoff points and calibration coefficients, the external characteristic charging efficiency curve of the naturally aspirated engine and the common operating conditions of the vehicle are highly matched, providing intake negative pressure reconstruction control parameters with optimal engineering performance.

[0011] In one possible embodiment, the step of correcting the maximum airflow torque request value of the engine based on the correction coefficient to obtain the corrected maximum airflow torque request value includes: the engine management system calculating the maximum permissible airflow torque of the engine under the current operating conditions; and multiplying the maximum permissible airflow torque by the correction coefficient to obtain the corrected maximum airflow torque request value.

[0012] In this implementation, the maximum airway torque product derating mechanism directly applies the control target to the upper limit of the intake opening at the engine bottom layer. The calculation architecture is simple and efficient, ensuring the real-time and deterministic nature of the throttle closed-loop response.

[0013] In one possible embodiment, controlling the engine operation based on the corrected maximum airflow torque request value includes: the engine management system sending the corrected maximum airflow torque request value to the power control unit; the power control unit acquiring the vehicle's required torque; and in response to the vehicle's required torque being greater than the corrected maximum airflow torque request value, the power control unit controlling the engine to output torque limited by the corrected maximum airflow torque request value, and controlling the drive motor to output compensating torque to meet the vehicle's required torque.

[0014] In this implementation, the electric drive-coordinated dynamic torque compensation mechanism uses the drive motor to transiently fill the power gap when the engine generates a vacuum due to active vacuum creation. This allows the vehicle to maintain its overall output torque without attenuation while performing efficient carbon canister desorption, ensuring excellent driving smoothness and power response quality.

[0015] In one possible embodiment, the magnitude of the compensated torque output by the drive motor corresponds to the difference between the vehicle's required torque and the corrected maximum air circuit torque request value.

[0016] In this implementation, the precise differential torque closed-loop distribution mechanism ensures a perfect match between the motor's electrical energy output and the engine's torque reduction, limiting sudden power changes and unnecessary waste of electrical energy.

[0017] In one possible embodiment, after acquiring the vehicle's altitude, ambient temperature, and the state of charge (SOC) of the power battery, the method further includes: acquiring the cumulative desorption flow rate of the carbon canister in real time; and acquiring the current engine speed when at least one of the following conditions is met: in response to the altitude being greater than a first preset threshold, the ambient temperature being greater than a second preset threshold, the SOC being greater than a third preset threshold, and the cumulative desorption flow rate being less than a preset flow rate threshold, acquiring the current engine speed.

[0018] In this implementation, the four-dimensional joint triggering and desorption state pre-closed-loop mechanism incorporates the actual desorption integral into the activation criterion, avoiding repeated intervention of the torque limiting strategy when the carbon canister has been emptied or desorption is sufficient, thus improving the rigor of control decisions.

[0019] In one possible embodiment, the process of obtaining the cumulative desorption flow rate of the carbon canister includes: obtaining the opening degree of the carbon canister desorption solenoid valve and the absolute pressure of the intake manifold; determining the instantaneous flow rate of carbon canister desorption based on the opening degree and the absolute pressure of the intake manifold; and integrating the instantaneous flow rate over time to obtain the cumulative desorption flow rate.

[0020] In this embodiment, the flow estimation mechanism based on the gas path pressure difference and the solenoid valve duty cycle eliminates the need for additional physical gas flow sensor hardware, achieving continuous and accurate quantification of the total desorption volume at extremely low cost.

[0021] In one possible embodiment, the method further includes: during engine operation controlled based on the modified maximum airway torque request value, in response to the cumulative desorption flow rate being greater than or equal to the preset flow rate threshold, exiting the modification of the maximum airway torque request value based on the modification coefficient and resuming normal torque control.

[0022] In this implementation, the closed-loop mechanism of "returning as soon as the target desorption amount is achieved" ensures that the engine torque limit is released immediately after the carbon canister reaches the predetermined emptying target, thus minimizing the engine's operating time under non-optimal conditions.

[0023] In one possible embodiment, the method further includes an exit control step: during engine operation controlled based on the corrected maximum airway torque request value, continuously monitoring the altitude, the ambient temperature, and the state of charge (SOC); in response to at least one of the following conditions being met: the altitude being less than or equal to the first preset threshold, the ambient temperature being less than or equal to the second preset threshold, and the SOC being less than or equal to the third preset threshold, exiting the correction of the maximum airway torque request value based on the correction coefficient and resuming normal torque control.

[0024] In this implementation, the multi-factor real-time dynamic circuit breaker protection mechanism terminates the strategy in a timely manner when the vehicle leaves the plateau, the environment cools down, or the battery charge drops below the safety threshold, effectively preventing over-discharge of the power battery and eliminating the risk of false torque during normal driving on flat ground.

[0025] In one possible embodiment, the exit from the correction of the maximum airway torque request value based on the correction coefficient includes: controlling the correction coefficient to monotonically increase to a value of 1.0 with a preset change slope.

[0026] In this implementation, the slope smooth transition exit mechanism eliminates the intake airflow roar and vehicle power jerking caused by the step release of engine air circuit torque when the strategy exits, significantly improving the smoothness of control condition switching.

[0027] In one possible embodiment, the first preset threshold is 1500 meters to 3000 meters; the second preset threshold is -10°C to 10°C; and the third preset threshold is 10% to 60%.

[0028] In this implementation, the wide threshold adaptive parameter configuration mechanism can flexibly adapt to the engineering requirements of different vehicle platforms and power battery capacities, ensuring the high robustness of the strategy under different climate and geographical environments.

[0029] Secondly, embodiments of this application provide a carbon canister desorption control system, comprising: a data acquisition module for acquiring the vehicle's altitude, ambient temperature, and the state of charge (SOC) of the power battery; a strategy judgment module for acquiring the current engine speed under at least one of the following conditions: the altitude is greater than a first preset threshold; the ambient temperature is greater than a second preset threshold; and the SOC is greater than a third preset threshold; a correction coefficient determination module for determining a correction coefficient corresponding to the current engine speed based on a preset correspondence between engine speed and correction coefficient; wherein the correction coefficient is a value greater than 0 and less than or equal to 1; a torque correction module for correcting the maximum air path torque request value of the engine based on the correction coefficient to obtain a corrected maximum air path torque request value; and a control execution module for controlling the engine operation based on the corrected maximum air path torque request value to perform carbon canister desorption.

[0030] The carbon canister desorption control system provided in this application embodiment achieves closed-loop control of the entire process, including multi-dimensional monitoring of operating conditions, dynamic speed mapping, active dederating of the gas path, and restricted negative pressure desorption, through close collaboration among various functional modules. It can significantly enhance the fuel vapor desorption capability of the carbon canister under high-altitude and low-pressure conditions without additional hardware costs, and comprehensively improve the environmental compliance and operational stability of the system.

[0031] Thirdly, embodiments of this application provide an electronic device, including: a memory storing a computer program thereon; and a processor coupled to the memory for running the computer program to implement the method provided by the first aspect or any possible implementation of the first aspect.

[0032] Fourthly, embodiments of this application provide a vehicle, including: an electronic device as described in the third aspect and a power control unit; the electronic device is communicatively connected to the power control unit and is used to send the corrected maximum airflow torque request value to the power control unit; the power control unit is used to control the naturally aspirated engine to operate at a torque limited by the corrected maximum airflow torque request value, and to control the drive motor to output compensated torque.

[0033] Fifthly, embodiments of this application provide a computer-readable storage medium having computer instructions stored thereon, which, when executed by a processor, implement the method provided as in the first aspect or any possible implementation thereof.

[0034] The beneficial effects in the third to fifth aspects are detailed in the section on the beneficial effects in the first aspect, and will not be repeated here.

[0035] The carbon canister desorption control method, system, and vehicle provided in this application embodiment can achieve the following technical effects: (1) Establish a multi-dimensional gating decision mechanism for environmental and vehicle energy conditions. Through multi-dimensional constraints of altitude, ambient temperature and battery SOC, accurately lock the plateau desorption conditions that are truly needed and have the ability to compensate for power, effectively avoiding unnecessary intervention in plains or power shortage conditions.

[0036] (2) Establish a fine correction coefficient mapping channel based on speed characteristics, get rid of the traditional coarse control of fixed torque limit, and implement differentiated air path control in the commonly used speed range and power transition range, taking into account both high negative pressure desorption efficiency and acceleration response quality.

[0037] (3) Construct an active attenuation and physical negative pressure reconstruction mechanism for the upper limit of torque in the air path dimension, directly limit the upper limit of engine intake air path torque at the bottom layer, and forcibly reduce the throttle opening to artificially create a high vacuum environment in the intake manifold, which greatly improves the carbon canister desorption and suction flow of the naturally aspirated engine in the thin air of the plateau.

[0038] (4) Design a closed-loop power coordination mechanism for electric drive differential power compensation and smooth exit. When the engine air circuit is limited in torque, the motor accurately fills the power difference and the slope is smoothly transitioned when exiting, eliminating the perception of power attenuation and jerking impact, taking into account both emission regulations compliance and the overall driving experience. Attached Figure Description

[0039] Figure 1 A schematic diagram of the implementation environment of the carbon canister desorption control method provided in the embodiments of this application is shown; Figure 2 A schematic flowchart of the carbon canister desorption control method provided in an embodiment of this application is shown; Figure 3 A schematic diagram showing the relationship between preset engine speed and correction coefficient is provided. Figure 4 A schematic diagram of the module structure of the carbon canister desorption control system provided in an embodiment of this application is shown. Detailed Implementation

[0040] To gain a more detailed understanding of the features and technical content of the embodiments of this disclosure, the implementation of the embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. The accompanying drawings are for reference and illustration only and are not intended to limit the embodiments of this disclosure.

[0041] First, the relevant technologies of the embodiments of this application will be described by way of example so that those skilled in the art can understand them.

[0042] The carbon canister is a core component of the vehicle's evaporative emission control system (EVAP), used to adsorb fuel vapors volatilized from the fuel tank, preventing them from being directly emitted into the atmosphere and causing environmental pollution. Under normal operating conditions, the negative pressure generated by the engine intake system (i.e., intake manifold vacuum) introduces the fuel vapors adsorbed in the carbon canister into the engine cylinders to participate in combustion, completing the carbon canister desorption process.

[0043] However, at high altitudes (plateaus), the atmospheric pressure is low and the air is thin, resulting in a significant decrease in engine intake air volume. This leads to insufficient negative pressure in the engine intake manifold, drastically reducing the desorption efficiency of conventional carbon canister desorption strategies. This problem is particularly pronounced in hybrid vehicles equipped with naturally aspirated engines.

[0044] First, naturally aspirated engines lack a forced turbocharger and are more dependent on the negative pressure of the intake manifold. Furthermore, hybrid vehicles typically operate in areas close to the engine's external characteristics (i.e., large throttle opening and high load) at high altitudes. In such conditions, the absolute pressure of the intake manifold is high and the negative pressure is extremely low, making it difficult to create a sufficient pressure difference to draw fuel vapor adsorbed by the carbon canister into the cylinder.

[0045] Secondly, the engine in a hybrid system frequently starts and stops during operation, which shortens the effective operating time of the engine and further compresses the effective desorption time window of the carbon canister.

[0046] While existing technologies offer solutions for adjusting engine load and desorption methods based on oxygen concentration or predicted power demand, these solutions do not adequately consider the unique operating conditions of naturally aspirated engines coupled with hybrid systems in high-altitude, low-pressure environments. Insufficient desorption from the carbon canister can easily lead to carbon canister saturation and fuel vapor overflow, resulting not only in fuel waste but also in excessive evaporative emissions, failing to meet stringent environmental emission regulations.

[0047] Based on this, this application provides a carbon canister desorption control method, system, and vehicle to solve the technical problem of low carbon canister desorption efficiency and excessive emissions caused by insufficient intake manifold negative pressure in existing naturally aspirated hybrid vehicles at high altitudes. Specifically, the carbon canister desorption control method in this embodiment can be applied to hybrid vehicles equipped with a naturally aspirated engine and a drive motor, and includes the following steps: acquiring vehicle status parameters in real time or periodically, the status parameters including at least the altitude of the vehicle's environment, ambient temperature, and the state of charge (SOC) of the power battery; determining whether the status parameters meet preset desorption enhancement activation conditions, wherein the desorption enhancement activation conditions include: altitude greater than a first preset threshold, ambient temperature greater than a second preset threshold, and SOC greater than a third preset threshold; in response to the activation conditions being met, determining that the vehicle is in a desorption enhancement condition and activating the carbon canister desorption enhancement strategy; and maintaining the carbon canister desorption enhancement strategy in the activated state. The engine's current speed is obtained; a correction coefficient corresponding to the current speed is determined according to the preset correspondence between engine speed and correction coefficient, wherein the correction coefficient is a value greater than 0 and less than or equal to 1; the maximum air path torque request value of the engine is corrected based on the correction coefficient to obtain the corrected maximum air path torque request value; the engine is controlled to operate at a torque limited by the corrected maximum air path torque request value to increase the negative pressure of the engine intake system and perform carbon canister desorption; during the execution of the carbon canister desorption enhancement strategy, in response to at least one of the activation conditions no longer being met, or the cumulative value of carbon canister desorption flow reaching the preset flow threshold, the carbon canister desorption enhancement strategy is exited and the engine's normal torque control is restored.

[0048] Thus, addressing the technical challenge of insufficient intake manifold negative pressure in hybrid vehicles equipped with naturally aspirated engines under high-altitude, low-pressure conditions, this technical solution actively limits the engine's maximum airflow torque request value through a correction coefficient. This prompts the engine to throttle and move away from operating regions close to its external characteristics, actively constructing a high intake negative pressure condition suitable for fuel vapor desorption. This significantly improves the desorption flow and efficiency of the carbon canister in high-altitude environments, effectively preventing excessive vehicle evaporative emissions caused by carbon canister saturation and fuel vapor overflow. By using multi-parameter joint logic judgment on altitude, ambient temperature, and the state of charge (SOC) of the power battery, it ensures that the desorption enhancement strategy is activated only under suitable conditions at high altitudes, where fuel evaporation is favorable and the power battery has sufficient energy to support the drive motor for torque compensation. This effectively avoids false triggering and excessive intervention in low-altitude plains, low-temperature conditions, or when the battery is low on charge, balancing vehicle economy, desorption requirements, and driving experience. Furthermore, a nonlinear mapping relationship between engine speed and the correction coefficient is established, implementing refined airflow torque limiting for different speed ranges. While ensuring basic power output and system stability during low-speed start-up and high-speed ranges, this solution enhances the desorption negative pressure in the commonly used low-to-medium speed operating range, improving the accuracy of intake control and desorption regulation across the entire speed range. This solution primarily relies on the collaborative implementation of internal control algorithms and strategies within the Engine Management System (EMS), Vehicle Controller Unit (VCU), and Power Control Unit (PCU). It eliminates the need for additional hardware structures such as negative pressure pumps, valve bodies, or dedicated sensors, offering advantages such as low modification costs, high system stability, and good compatibility with existing vehicle electronic and electrical architectures. This facilitates rapid engineering application and platform-based promotion across various hybrid vehicle models.

[0049] This application provides a carbon canister desorption control method, a carbon canister desorption control system, an electronic device, a vehicle, and a computer-readable storage medium, applicable to hybrid vehicles equipped with naturally aspirated engines. Optionally, the hybrid vehicle can be a plug-in hybrid electric vehicle, a hybrid electric vehicle, or other vehicles equipped with both an engine and a drive motor.

[0050] Based on the above description, the implementation environment of the carbon canister desorption control method in the embodiments of this application is described below.

[0051] Figure 1 A schematic diagram illustrating the implementation environment of the carbon canister desorption control method provided in this application embodiment is shown. Figure 1As shown, the implementation environment may include a vehicle 101, an environmental parameter acquisition device 102, a power battery management device 103, an engine management system (EMS) 104, a power control unit (PCU) 105, a carbon canister desorption control system 106, and a drive motor 107.

[0052] Among them, vehicle 101 includes, but is not limited to, hybrid electric vehicles (HEV), plug-in hybrid electric vehicles (PHEV), and new energy vehicles equipped with naturally aspirated engines and drive motors.

[0053] The environmental parameter acquisition device 102 is used to collect the altitude and ambient temperature of the vehicle's environment. The environmental parameter acquisition device 102 may include an environmental pressure sensor, an ambient temperature sensor, a positioning device, or other devices capable of determining the vehicle's altitude and ambient temperature.

[0054] In one implementation, an ambient pressure sensor collects the atmospheric pressure at the vehicle's location, and the vehicle controller calculates the vehicle's altitude based on this atmospheric pressure. The vehicle's altitude can also be obtained from a positioning device, or determined jointly by the ambient pressure sensor and the positioning device. When multiple devices are used to obtain altitude data, the altitude parameter used for control can be obtained through filtering, averaging, or validity verification.

[0055] The power battery management device 103 is used to detect the state of charge (SOC) of the power battery and send the detected SOC to the vehicle controller, engine management system (EMS) 104, or power control unit (PCU) 105. It should be understood that the SOC can be calculated by the power battery management system (BMS) based on parameters such as current integral, open-circuit voltage, charge / discharge power, and battery temperature.

[0056] For example, the engine management system (EMS) 104 calculates the maximum airflow torque request value of the engine under the current operating conditions, determines a correction factor based on the current engine speed, and corrects the maximum airflow torque request value. The EMS 104 can also control actuators such as the engine throttle, fuel injection, ignition, and carbon canister desorption solenoid valve.

[0057] The power control unit PCU 105 communicates with the engine management system EMS 104 to receive the corrected maximum airflow torque request value and coordinate the control of the engine and drive motor according to the vehicle's required torque. When the engine output torque is limited, the power control unit PCU 105 can control the drive motor 107 to output compensating torque to meet the vehicle's power requirements.

[0058] Optionally, the carbon canister desorption control system 106 may include a fuel tank, a carbon canister, a carbon canister desorption solenoid valve, a desorption pipeline, and an engine intake system. The carbon canister is used to adsorb fuel vapor generated in the fuel tank. The carbon canister desorption solenoid valve is located between the carbon canister and the engine intake system and is used to control the connection status and degree between the carbon canister and the engine intake system. When the carbon canister desorption solenoid valve is open, the negative pressure generated by the engine intake system can introduce the fuel vapor adsorbed in the carbon canister into the engine cylinder to participate in combustion, thereby realizing carbon canister desorption.

[0059] Based on the above implementation environment, the complete process of the carbon canister desorption control method provided in the embodiments of this application will be described by way of example below.

[0060] Figure 2 A schematic flowchart of the carbon canister desorption control method provided in this application embodiment is shown. This method can be executed collaboratively by the engine management system (EMS), vehicle control unit (VCU), and power control unit (PCU), or executed by the controller. The controller can be a domain controller integrating EMS functions or a standalone VCU. The method includes the following steps S201-S205.

[0061] S201. Obtain the vehicle's altitude, ambient temperature, and the state of charge (SOC) of the power battery.

[0062] In one implementation, the controller acquires the aforementioned vehicle state parameters at a preset sampling period. The sampling period can be 100 milliseconds, 500 milliseconds, 1 second, or other preset time periods. To avoid frequent switching of control strategies caused by instantaneous fluctuations in sensor readings, the controller can filter the altitude, ambient temperature, and state of charge (SOC).

[0063] For example, the controller can continuously acquire altitude data over multiple sampling periods and perform a moving average of these altitudes to obtain the altitude used for policy judgment. Ambient temperature can be acquired via a temperature sensor, and the State of Charge (SOC) can be periodically sent from the BMS to the EMS or VCU.

[0064] In one implementation, subsequent carbon canister desorption control is performed when the vehicle is in an engine-operated, hybrid-operated, or engine-start-allowed state. When the vehicle is in a state of engine shutdown, maintenance, malfunction, or engine operation is not permitted, the control method may not be performed, or conventional carbon canister desorption control logic may be maintained.

[0065] Thus, this embodiment, by jointly judging altitude, ambient temperature and power battery SOC, can selectively activate the desorption enhancement strategy according to the actual environmental state and energy state of the vehicle, thereby reducing unnecessary engine torque limiting control.

[0066] S202. Obtain the current engine speed if at least one of the following conditions is met: the altitude is greater than a first preset threshold; the ambient temperature is greater than a second preset threshold; the state of charge (SOC) is greater than a third preset threshold.

[0067] In other words, the controller makes independent or combined judgments on altitude, ambient temperature, and power battery SOC.

[0068] In this application, the first preset threshold, the second preset threshold, and the third preset threshold can be determined based on the engine type, carbon canister capacity, fuel characteristics, power battery capacity, and vehicle calibration requirements.

[0069] For example, the first preset threshold can be 1500 meters, 2000 meters, 2500 meters or 3000 meters; the second preset threshold can be -10℃, 0℃ or 10℃; the third preset threshold can be 10%, 30%, 50% or 60%.

[0070] As a specific example, when the first preset threshold is set to 1500 meters, the second preset threshold is set to 10℃, and the third preset threshold is set to 10%, if the vehicle's altitude is 1800 meters, the ambient temperature is 15℃, and the power battery SOC is 35%, then the three activation conditions are met simultaneously. The controller obtains the current engine speed and performs subsequent correction control.

[0071] When the vehicle's altitude is 1200 meters, the ambient temperature and SOC meet the corresponding conditions. Even if the altitude is not greater than 1500 meters, the controller can still activate the desorption enhancement strategy. The desorption enhancement strategy can also be activated when the ambient temperature is 5℃ or the SOC is 8%.

[0072] In some implementations, hysteresis intervals can be set for determining altitude, ambient temperature, and state of charge (SOC). For example, activation requires an altitude greater than a first activation threshold, while deactivation requires an altitude less than or equal to a first deactivation threshold, with the first activation threshold being greater than the first deactivation threshold, to reduce frequent entry and exit near boundary values. The hysteresis interval can be set according to vehicle calibration requirements.

[0073] S203. Based on the preset correspondence between engine speed and correction coefficient, determine the correction coefficient corresponding to the current speed. The correction coefficient is a value greater than 0 and less than or equal to 1.

[0074] Optionally, the correspondence between engine speed and correction coefficient can be stored in the memory of the engine management system (EMS), vehicle controller (VCU), or power control unit (PCU), and implemented in the form of a data table, calibration curve, or mapping relationship.

[0075] In one embodiment, determining a correction coefficient corresponding to the current engine speed based on a preset correspondence between engine speed and correction coefficient includes: determining that, in response to the current engine speed being in the range from zero to a first engine speed, the correction coefficient monotonically decreases from a first coefficient value to a second coefficient value; determining that, in response to the current engine speed being in the range from the first engine speed to the second engine speed, the correction coefficient remains at the second coefficient value; determining that, in response to the current engine speed being in the range from the second engine speed to the third engine speed, the correction coefficient monotonically increases from the second coefficient value to a third coefficient value; determining that, in response to the current engine speed being in the range from the third engine speed to the fourth engine speed, the correction coefficient remains at the third coefficient value; determining that, in response to the current engine speed being in the range from the fourth engine speed to the fifth engine speed, the correction coefficient monotonically decreases from the third coefficient value to the fourth coefficient value; and determining that, in response to the current engine speed being in the range from the fifth engine speed to the sixth engine speed, the correction coefficient remains at the fourth coefficient value; wherein the first coefficient value is greater than the third coefficient value, the third coefficient value is greater than the second coefficient value, and the second coefficient value is greater than the fourth coefficient value.

[0076] It should be noted that, in this embodiment, "monotonically decreasing" can refer to linear decreasing, piecewise linear decreasing, or decreasing according to a preset curve; "monotonically increasing" can refer to linear increasing, piecewise linear increasing, or increasing according to a preset curve. For the current speed at the boundary of an adjacent speed range, a correction coefficient can be determined according to a pre-set boundary assignment rule.

[0077] In one specific embodiment, the first speed is 1000 rpm, the second speed is 2400 rpm, the third speed is 2500 rpm, the fourth speed is 4400 rpm, and the fifth speed is 5500 rpm; the first coefficient is 1.0, the second coefficient is 0.7, the third coefficient is 0.8, and the fourth coefficient is 0.6.

[0078] Figure 3 A schematic diagram showing the relationship between preset engine speed and correction coefficient is provided. (This is related to...) Figure 3 In this embodiment, when the current engine speed is in the range of 0 rpm to 1000 rpm, the correction coefficient monotonically decreases from 1.0 to 0.7; when the current engine speed is in the range of 1000 rpm to 2400 rpm, the correction coefficient remains at 0.7; when the current engine speed is in the range of 2400 rpm to 2500 rpm, the correction coefficient monotonically increases from 0.7 to 0.8; when the current engine speed is in the range of 2500 rpm to 4400 rpm, the correction coefficient remains at 0.8; when the current engine speed is in the range of 4400 rpm to 4500 rpm, the correction coefficient monotonically decreases from 0.8 to 0.6; and when the current engine speed is in the range of 4500 rpm to 5500 rpm, the correction coefficient remains at 0.6.

[0079] For example, when the current engine speed is 800 rpm, the correction factor can be determined based on the decreasing curve from 0 rpm to 1000 rpm; when the current engine speed is 1800 rpm, the correction factor is 0.7; when the current engine speed is 2450 rpm, the correction factor can be determined based on the increasing curve from 0.7 to 0.8; when the current engine speed is 3500 rpm, the correction factor is 0.8; and when the current engine speed is 5000 rpm, the correction factor is 0.6.

[0080] The specific speed ranges and coefficient values ​​mentioned above are only examples. In actual applications, they can be recalibrated based on engine bench tests, vehicle road tests, emission tests, and power requirements.

[0081] Thus, this embodiment, by establishing the correspondence between engine speed and correction coefficient, can implement differentiated airflow torque control for different engine speed ranges, improving control accuracy. Furthermore, by using the correction coefficient to correct the maximum airflow torque request value, the engine airflow torque can be limited, enabling the engine to achieve an intake state suitable for carbon canister desorption in high-altitude, low-pressure environments, thereby improving carbon canister desorption efficiency.

[0082] S204. The maximum air path torque request value of the engine is corrected based on the correction coefficient to obtain the corrected maximum air path torque request value.

[0083] In one implementation, the engine management system (EMS) calculates the maximum permissible air path torque of the engine under the current operating conditions, and multiplies the maximum permissible air path torque by a correction factor to obtain the corrected maximum air path torque request value.

[0084] Specifically, the Engine Management System (EMS) can determine the maximum permissible airflow torque of the engine under current operating conditions based on parameters such as engine speed, intake air temperature, ambient pressure, throttle position, engine coolant temperature, fuel injection status, and engine protection limits. Let the maximum permissible airflow torque be... The correction factor is The revised maximum air path torque request value is ,but:

[0085] because Therefore, the revised maximum air circuit torque request value is not greater than the maximum permissible air circuit torque under the current operating conditions.

[0086] For example, when the maximum permissible airflow torque of the engine under the current operating conditions is 100 N·m, and the correction factor corresponding to the current speed is 0.7, the corrected maximum airflow torque request value is 70 N·m. When the maximum permissible airflow torque is 150 N·m, and the correction factor is 0.8, the corrected maximum airflow torque request value is 120 N·m.

[0087] In one implementation, the modified maximum airway torque request value can be sent to the power control unit (PCU) as the engine airway torque limit, or it can be further converted by the EMS into a throttle opening limit, intake volume limit, or engine load limit. By limiting the engine airway torque request value, the engine is prevented from operating at a large throttle opening or close to its external characteristics for extended periods, thereby providing suitable intake pressure conditions for fuel vapor to enter the engine intake system for carbon canister desorption.

[0088] Thus, in this embodiment, by controlling the output compensation torque of the drive motor through the power control unit, the power demand of the whole vehicle can be met when the engine performs desorption enhancement control, thereby reducing the impact of the decline in vehicle power on the driving experience.

[0089] S205: Control engine operation based on the modified maximum airflow torque request value to perform carbon canister desorption.

[0090] In one implementation, the engine management system (EMS) sends the corrected maximum airflow torque request value to the power control unit (PCU); the power control unit (PCU) obtains the vehicle's required torque; in response to the vehicle's required torque being greater than the corrected maximum airflow torque request value, the power control unit (PCU) controls the engine to output torque limited by the corrected maximum airflow torque request value, and controls the drive motor to output compensating torque to meet the vehicle's required torque.

[0091] For example, if the vehicle requires a torque of 120 N·m and the corrected maximum air path torque request value is 80 N·m, the power control unit (PCU) will limit the engine's air path torque to no more than 80 N·m and control the drive motor to participate in the output to meet the vehicle's torque requirements.

[0092] During engine operation, the carbon canister desorption solenoid valve can be opened according to the conventional desorption control strategy. After a pressure difference is formed between the engine intake system and the carbon canister, the fuel vapor adsorbed in the carbon canister enters the engine intake system through the desorption pipeline and participates in combustion in the engine cylinder, thereby completing the carbon canister desorption.

[0093] In some implementations, when the required torque of the vehicle is less than or equal to the modified maximum air circuit torque request value, the power control unit (PCU) can control the engine to output the torque required by the vehicle, or control the engine and drive motor to output torque together according to the energy management strategy of the hybrid system.

[0094] Next, an exemplary description of drive motor compensation control will be provided.

[0095] In one implementation, the magnitude of the compensated torque output by the drive motor corresponds to the difference between the vehicle's required torque and the corrected maximum airflow torque request value.

[0096] Let the required torque of the whole vehicle be The revised maximum air path torque request value is The compensation torque of the drive motor is When the required torque of the vehicle is greater than the corrected maximum air circuit torque request value, the compensation torque can be determined according to the following formula:

[0097] For example, when the total vehicle torque requirement is 120 N·m and the corrected maximum air circuit torque requirement is 80 N·m, the compensation torque output by the drive motor can be 40 N·m.

[0098] In actual control, the power control unit (PCU) can also limit the compensation torque based on the maximum permissible torque of the drive motor, the maximum discharge power of the power battery, battery temperature, motor temperature, and vehicle stability constraints. When the drive motor cannot fully compensate for the difference, the PCU can output the compensation torque according to the maximum available motor torque and coordinate the engine torque request based on the vehicle's operating status.

[0099] Next, we will provide an exemplary description of activation and deactivation control based on the cumulative value of desorption flow.

[0100] In one implementation, after acquiring the vehicle's altitude, ambient temperature, and the state of charge (SOC) of the power battery, the method further includes acquiring the cumulative desorption flow rate of the carbon canister in real time.

[0101] At this time, in response to the altitude being greater than the first preset threshold, the ambient temperature being greater than the second preset threshold, the SOC being greater than the third preset threshold, and the cumulative desorption flow rate being less than the preset flow rate threshold, the current engine speed is obtained.

[0102] The preset flow rate threshold is used to indicate that the carbon canister has reached the target desorption capacity. The preset flow rate threshold can be calibrated based on the carbon canister's adsorption capacity, fuel vapor production, desorption pipeline structure, and emission regulations. For example, the preset flow rate threshold can be set to 200L, or other volume values ​​depending on the specific vehicle model.

[0103] When the cumulative desorption flow rate has reached the preset flow rate threshold, the desorption enhancement strategy can be deactivated even if the altitude, ambient temperature, and SOC all meet the activation conditions, thereby avoiding repeated execution of torque limiting control.

[0104] In one embodiment, the process of obtaining the cumulative desorption flow rate of the carbon canister includes: obtaining the opening degree of the carbon canister desorption solenoid valve and the absolute pressure of the intake manifold; determining the instantaneous flow rate of carbon canister desorption based on the opening degree and the absolute pressure of the intake manifold; and integrating the instantaneous flow rate over time to obtain the cumulative desorption flow rate.

[0105] Specifically, the controller can calculate the instantaneous flow rate of carbon canister desorption based on the opening degree of the carbon canister desorption solenoid valve, the absolute pressure of the intake manifold, the ambient pressure, the intake temperature, and the calibration parameters of the desorption pipeline, either by looking up a table or through a preset flow model. Let the instantaneous flow rate be... The sampling period is Then the cumulative value of desorption flow It can be calculated using the following formula:

[0106] Or it can be expressed as:

[0107] For example, within a certain sampling period, if the carbon canister desorption solenoid valve opening is 30%, the intake manifold absolute pressure is 40 kPa, and the controller determines the instantaneous flow rate to be 10 L / min based on a pre-stored flow calibration table, with a sampling period of 1 second, then the desorption flow rate increment corresponding to this sampling period is approximately 0.167 L. The controller accumulates the desorption flow rate increments for each sampling period to obtain the cumulative desorption flow rate value.

[0108] In another implementation, the instantaneous flow rate can be directly obtained by a flow sensor installed in the desorption pipeline, and then the instantaneous flow rate can be integrated over time to obtain the cumulative value of the desorption flow rate.

[0109] Next, an example of exiting the desorption enhancement strategy will be provided.

[0110] In some implementations, during engine operation controlled based on the modified maximum airway torque request value, in response to the cumulative desorption flow rate being greater than or equal to a preset flow rate threshold, the modification of the maximum airway torque request value based on the correction coefficient is exited, and normal torque control is restored.

[0111] For example, when the preset flow threshold is 200L and the controller detects that the cumulative desorption flow has reached 200L, the controller exits the desorption enhancement strategy. After exiting, the engine management system (EMS) determines the maximum air path torque request value of the engine according to the conventional control logic, and the power control unit (PCU) controls the engine and drive motor according to the conventional hybrid torque distribution strategy.

[0112] Thus, by integrating the instantaneous desorption flow rate of the carbon canister over time to obtain the cumulative desorption flow rate, and using the cumulative desorption flow rate as the basis for activation or deactivation, insufficient carbon canister desorption or repeated execution of desorption enhancement strategies can be avoided.

[0113] In another implementation, during engine operation controlled based on the corrected maximum airflow torque request value, altitude, ambient temperature, and state of charge (SOC) are continuously monitored. In response to at least one of the following conditions being met: altitude less than or equal to a first preset threshold, ambient temperature less than or equal to a second preset threshold, and SOC less than or equal to a third preset threshold, the correction of the maximum airflow torque request value based on the correction coefficient is terminated, and normal torque control is resumed.

[0114] For example, during strategy execution, when the vehicle moves from an altitude of 1800 meters to an altitude of 1400 meters, and the altitude is less than or equal to the first preset threshold, the controller exits the desorption enhancement strategy. Similarly, when the ambient temperature drops below the second preset threshold, or the power battery SOC drops below the third preset threshold, the controller also exits the strategy.

[0115] In one implementation, to avoid a sudden power shock caused by the engine torque suddenly recovering when the correction strategy is exited, exiting the correction based on the maximum air circuit torque request value includes: controlling the correction coefficient to monotonically increase to a value of 1.0 with a preset change slope.

[0116] For example, when exiting the strategy, if the current correction coefficient is 0.6, the controller can gradually adjust the correction coefficient to 0.7, 0.8, 0.9, and finally to 1.0 according to a preset change slope. As the correction coefficient gradually increases, the engine's maximum airflow torque request value gradually returns to the normal control value, thereby reducing the vehicle shock caused by abrupt changes in engine torque.

[0117] Thus, in this embodiment, by gradually increasing the correction coefficient to 1.0 according to a preset change slope when exiting the desorption enhancement strategy, the power shock caused by sudden torque changes can be reduced, and the smoothness of the control process can be improved.

[0118] In some implementations, when an engine failure, power battery failure, drive motor failure, communication failure, or vehicle safety control intervention occurs, the desorption enhancement strategy can be immediately discontinued, or conventional torque control can be restored according to the fault control strategy.

[0119] In one embodiment, the first preset threshold is 1500 meters to 3000 meters; the second preset threshold is -10°C to 10°C; and the third preset threshold is 10% to 60%. For example, the first preset threshold can be set to 1500 meters; the second preset threshold can be set to 10°C; the third preset threshold can be set to 10%; and the preset flow rate threshold can be set to 200L.

[0120] In this example, when the altitude is greater than 1500 meters, the ambient temperature is greater than 10°C, the SOC of the power battery is greater than 10%, and the cumulative desorption flow rate is less than 200L, the controller activates the desorption enhancement strategy.

[0121] It should be understood that the above thresholds are not fixed. For models with larger carbon canister capacities, higher fuel volatility, or weaker engine adaptability at high altitudes, the altitude threshold or temperature threshold can be appropriately increased. For models with smaller battery capacities or limited battery discharge capacity, the SOC threshold can be increased to ensure that the drive motor can provide sufficient torque compensation for engine torque limiting.

[0122] Based on the above method embodiments, this application also provides a carbon canister desorption control system.

[0123] Figure 4 A schematic diagram of the module structure of the carbon canister desorption control system provided in an embodiment of this application is shown. The carbon canister desorption control system 400 includes a data acquisition module 401, a strategy judgment module 402, a correction coefficient determination module 403, a torque correction module 404, and a control execution module 405.

[0124] The data acquisition module 401 is used to acquire the vehicle's altitude, ambient temperature, and the state of charge (SOC) of the power battery. The data acquisition module 401 can acquire relevant signals through sensor interfaces, CAN bus, vehicle Ethernet, or other vehicle communication interfaces.

[0125] The strategy determination module 402 is used to obtain the current engine speed when at least one of the following conditions is met: the altitude is greater than a first preset threshold; the ambient temperature is greater than a second preset threshold; and the state of charge (SOC) is greater than a third preset threshold. The strategy determination module 402 can also obtain the cumulative desorption flow rate and compare it with a preset flow rate threshold to determine whether to activate or deactivate the desorption enhancement strategy.

[0126] The correction coefficient determination module 403 is used to determine the correction coefficient corresponding to the current engine speed based on a preset correspondence between engine speed and correction coefficient. The correction coefficient is a value greater than 0 and less than or equal to 1. The correction coefficient determination module 403 can determine the correction coefficient through table lookup, interpolation, or curve calculation.

[0127] The torque correction module 404 is used to correct the maximum airflow torque request value of the engine based on the correction coefficient, to obtain the corrected maximum airflow torque request value. The torque correction module 404 can be located in the EMS, or in the VCU or other power domain controllers.

[0128] The control execution module 405 is used to control the engine operation based on the corrected maximum airflow torque request value to perform carbon canister desorption. The control execution module 405 may consist of one or more of an EMS, a PCU, an engine throttle controller, and a carbon canister desorption solenoid valve controller.

[0129] The modules described above can be implemented in software, hardware, or a combination of both. Different modules can be deployed on the same processor or on different processors that can communicate with each other. The module division is for illustrating the corresponding functions and does not constitute a limitation on the actual software or hardware architecture.

[0130] The specific execution methods of each module in the carbon canister desorption control system 400 have been described in detail in the above method embodiments. The system embodiments and method embodiments belong to the same inventive concept, and the relevant contents can be referred to each other.

[0131] The embodiments of this application are mainly implemented through control strategies and software logic, without the need to add a separate negative pressure pump or other dedicated hardware, which has lower modification costs and better engineering application adaptability.

[0132] This application also provides an electronic device. The electronic device includes a memory and a processor. A computer program is stored in the memory. The processor is coupled to the memory and is used to run the computer program to implement the carbon canister desorption control method provided in any of the above embodiments.

[0133] The electronic device may be an engine controller, vehicle controller, power domain controller, domain controller, or other vehicle control device. The processor may be a microprocessor, microcontroller, digital signal processor, field-programmable gate array, or other processor with data processing capabilities. The memory may be a read-only memory, random access memory, flash memory, hard disk, or other storage medium capable of storing computer programs.

[0134] This application also provides a vehicle, which includes the aforementioned electronic device and a power control unit (PCU). The electronic device is communicatively connected to the power control unit and is used to send the corrected maximum airflow torque request value to the power control unit. The power control unit is used to control the naturally aspirated engine to operate at a torque limited by the corrected maximum airflow torque request value and to control the drive motor to output compensated torque.

[0135] The vehicle may also include an ambient pressure sensor, an ambient temperature sensor, a battery management system (BMS), a carbon canister desorption solenoid valve, an engine throttle valve, a drive motor, and an on-board communication network for connecting the above components.

[0136] When the vehicle is at high altitude, in suitable temperature, and with a sufficient SOC of the power battery, the electronic equipment determines a correction coefficient based on the current engine speed and corrects the engine's maximum airflow torque request value. After receiving the corrected maximum airflow torque request value, the PCU limits the engine's airflow torque and, if necessary, controls the drive motor to output compensating torque. At the same time, the carbon canister desorption solenoid valve opens according to the desorption control strategy, allowing fuel vapor from the carbon canister to enter the engine's intake system and participate in combustion.

[0137] This application also provides a computer-readable storage medium storing computer instructions thereon. When the computer instructions are executed by a processor, they implement the carbon canister desorption control method provided in any of the above embodiments.

[0138] The computer-readable storage medium may include a read-only memory, a random access memory, a magnetic disk, an optical disk, flash memory, or other media capable of storing computer instructions.

[0139] This application provides a computer program including computer-readable code, wherein when the computer-readable code is executed in an electronic device, a processor in the electronic device performs some or all of the steps in the above-described method.

[0140] This application provides a computer program product, which includes a non-transitory computer-readable storage medium storing a computer program. When the computer program is read and executed by a computer, it implements some or all of the steps in the above-described method. This computer program product can be implemented specifically through hardware, software, or a combination thereof. In some embodiments, the computer program product is specifically embodied as a computer storage medium; in other embodiments, the computer program product is specifically embodied as a software product, such as a software development kit (SDK), etc.

[0141] It should be noted that the technical features in the various embodiments of this application can be combined arbitrarily. As long as the combined technical solutions do not contradict each other, they should all be considered as part of the content disclosed in this application. The above descriptions are merely specific embodiments of this application and are not intended to limit the scope of protection of this application. For those skilled in the art, equivalent substitutions, simple transformations, or improvements made without departing from the technical concept of this application should all be included within the scope of protection of this application.

Claims

1. A method for controlling carbon canister desorption, characterized in that, include: It acquires the vehicle's altitude, ambient temperature, and the state of charge (SOC) of the power battery. The current engine speed is obtained if at least one of the following conditions is met: the altitude is greater than a first preset threshold; the ambient temperature is greater than a second preset threshold; or the state of charge (SOC) is greater than a third preset threshold. Based on the preset correspondence between engine speed and correction coefficient, a correction coefficient corresponding to the current engine speed is determined; wherein, the correction coefficient is a value greater than 0 and less than or equal to 1. The maximum airflow torque request value of the engine is corrected based on the correction coefficient to obtain the corrected maximum airflow torque request value; and The engine is controlled to perform carbon canister desorption based on the modified maximum airflow torque request value.

2. The method according to claim 1, characterized in that, The step of determining the correction coefficient corresponding to the current engine speed based on a preset correspondence between engine speed and correction coefficient includes: In response to the current rotational speed being in the range of zero to a first rotational speed, it is determined that the correction coefficient decreases monotonically from a first coefficient value to a second coefficient value; In response to the current rotational speed being within the range of a first rotational speed to a second rotational speed, the correction coefficient is determined to remain at the second coefficient value; In response to the current speed being in the range between the second and third speeds, it is determined that the correction coefficient increases monotonically from the second coefficient value to the third coefficient value; In response to the current rotational speed being in the range of the third to the fourth rotational speed, the correction coefficient is determined to remain at the third coefficient value; In response to the current speed being in the range of fourth to fifth speed, the correction coefficient is determined to decrease monotonically from the third coefficient value to the fourth coefficient value; and In response to the current speed being in the range of the fifth to the sixth speed, the correction coefficient is determined to remain at the fourth coefficient value; Wherein, the first coefficient value is greater than the third coefficient value, the third coefficient value is greater than the second coefficient value, and the second coefficient value is greater than the fourth coefficient value.

3. The method according to claim 1, characterized in that, The step of correcting the maximum airflow torque request value of the engine based on the correction coefficient to obtain the corrected maximum airflow torque request value includes: The engine management system calculates the maximum permissible airflow torque of the engine under the current operating conditions; and Multiply the maximum permissible air path torque by the correction coefficient to obtain the corrected maximum air path torque request value.

4. The method according to any one of claims 1 to 3, characterized in that, Controlling engine operation based on the corrected maximum airflow torque request value includes: The engine management system sends the corrected maximum airflow torque request value to the power control unit; The power control unit acquires the required torque for the entire vehicle; and In response to the vehicle's required torque being greater than the corrected maximum airflow torque request value, the power control unit controls the engine to output torque limited by the corrected maximum airflow torque request value, and controls the drive motor to output compensating torque to meet the vehicle's required torque.

5. The method according to claim 4, characterized in that, The magnitude of the compensation torque output by the drive motor corresponds to the difference between the vehicle's required torque and the corrected maximum air circuit torque request value.

6. The method according to any one of claims 1 to 3, characterized in that, After obtaining the vehicle's altitude, ambient temperature, and the state of charge (SOC) of the power battery, the method further includes: Real-time acquisition of the cumulative desorption flow rate of the carbon canister; Obtain the current engine speed if at least one of the following conditions is met: In response to the altitude being greater than a first preset threshold, the ambient temperature being greater than a second preset threshold, the state of charge (SOC) being greater than a third preset threshold, and the cumulative desorption flow rate being less than a preset flow rate threshold, the current speed of the engine is obtained.

7. The method according to claim 6, characterized in that, The process of obtaining the cumulative desorption flow rate of the carbon canister includes: Obtain the opening degree of the carbon canister desorption solenoid valve and the absolute pressure of the intake manifold; The instantaneous flow rate for carbon canister desorption is determined based on the opening degree and the absolute pressure of the intake manifold; and The cumulative value of the desorption flow rate is obtained by integrating the instantaneous flow rate over time.

8. The method according to claim 6, characterized in that, The method further includes: During engine operation controlled based on the corrected maximum airway torque request value, in response to the cumulative desorption flow rate being greater than or equal to the preset flow rate threshold, the correction of the maximum airway torque request value based on the correction coefficient is exited, and normal torque control is restored.

9. The method according to any one of claims 1 to 3, characterized in that, The method also includes an exit control step: During engine operation controlled based on the corrected maximum airflow torque request value, the altitude, ambient temperature, and state of charge (SOC) are continuously monitored. In response to the condition that at least one of the following conditions is met—the altitude being less than or equal to the first preset threshold, the ambient temperature being less than or equal to the second preset threshold, and the SOC being less than or equal to the third preset threshold—the correction of the maximum air path torque request value based on the correction coefficient is terminated, and normal torque control is restored.

10. The method according to claim 9, characterized in that, The exit based on the correction coefficient for the maximum air path torque request value includes: The correction coefficient is controlled to monotonically increase to a value of 1.0 with a preset change slope.

11. A carbon canister desorption control system, characterized in that, include: The data acquisition module is used to obtain the vehicle's altitude, ambient temperature, and the state of charge (SOC) of the power battery. The strategy judgment module is used to obtain the current engine speed in response to the altitude being greater than a first preset threshold, the ambient temperature being greater than a second preset threshold, and the SOC being greater than a third preset threshold. The correction coefficient determination module is used to determine the correction coefficient corresponding to the current engine speed based on a preset correspondence between engine speed and correction coefficient; wherein the correction coefficient is a value greater than 0 and less than or equal to 1. A torque correction module is used to correct the maximum airflow torque request value of the engine based on the correction coefficient, to obtain a corrected maximum airflow torque request value; and The control execution module is used to control the engine operation based on the corrected maximum airway torque request value to perform carbon canister desorption.

12. An electronic device, characterized in that, include: Memory, on which computer programs are stored; and A processor, coupled to the memory, is used to run the computer program to implement the method as described in any one of claims 1 to 10.

13. A vehicle, characterized in that, include: The electronic device and power control unit as described in claim 12; The electronic device is communicatively connected to the power control unit and is used to send the corrected maximum air path torque request value to the power control unit. The power control unit controls the naturally aspirated engine to operate at a torque limited by the modified maximum airflow torque request value, and controls the drive motor to output compensated torque.

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