Control methods, devices, on-board controllers, and vehicles for carbon canister flushing

Abstract

This application relates to the field of automotive technology and provides a control method, device, on-board controller, and vehicle for carbon canister flushing. The method includes: acquiring parameter information of the vehicle's engine; determining the engine's operating condition based on the parameter information; performing a carbon canister flushing operation if the operating condition is a steady-state condition; and not performing a carbon canister flushing operation if the operating condition is a dynamic condition. This application performs the carbon canister flushing operation only when the engine is operating under steady-state conditions, making the carbon canister fuel concentration determined during flushing more accurate. This solves the problem of unstable idling or even stalling during flushing caused by obtaining incorrect carbon canister fuel concentrations, especially artificially high concentrations. Simultaneously, not performing the carbon canister flushing operation when the engine is operating under dynamic conditions avoids obtaining incorrect carbon canister fuel concentrations under dynamic conditions, further preventing unstable idling or even stalling during flushing due to incorrect carbon canister fuel concentrations.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of automobiles, and particularly relates to a control method and device for carbon canister purging, a vehicle-mounted controller and a vehicle. BACKGROUND

[0002] Currently, fuel vapor accumulated in the fuel tank of a vehicle will cause the pressure in the fuel tank to rise. In order to solve this problem, the fuel vapor volatilized in the fuel tank is introduced into a carbon canister with adsorption function for storage. Then, when the carbon canister is purged, fresh air in the external environment is used to purge the carbon canister, and the purged air and the fuel desorbed from the carbon canister are re-introduced into the engine for combustion, so as to save fuel and reduce fuel vapor emission.

[0003] However, the prior art usually directly purges the carbon canister. Therefore, the prior art does not comprehensively consider the carbon canister purging, which can easily cause unstable idling or even engine stall during carbon canister purging. SUMMARY

[0004] The embodiments of the application provide a control method and device for carbon canister purging, a vehicle-mounted controller and a vehicle, so as to solve the problem that the prior art does not comprehensively consider carbon canister purging, which can easily cause unstable idling or even engine stall during carbon canister purging.

[0005] In a first aspect, the embodiments of the application provide a control method for carbon canister purging, comprising:

[0006] obtaining parameter information of an engine of a vehicle;

[0007] determining a working condition of the engine based on the parameter information;

[0008] if the working condition is a steady-state condition, performing a carbon canister purging operation;

[0009] if the working condition is a dynamic condition, not performing the carbon canister purging operation.

[0010] Optionally, the determining of the working condition of the engine based on the parameter information comprises:

[0011] filtering the parameter information to obtain target information;

[0012] if a difference between the parameter information and the target information meets a set condition, determining that the working condition is the steady-state condition.

[0013] Optionally, the parameter information comprises a current average indicated pressure and a current intake air amount; and the filtering of the parameter information to obtain target information comprises:

[0014] The target average indicated pressure is obtained by performing a first-order delay filter on the current average indicated pressure based on the first filter coefficient.

[0015] The target air intake volume is obtained by performing a first-order delay filter on the current air intake volume based on the second filter coefficient; the second filter coefficient is different from the first filter coefficient.

[0016] Accordingly, determining the operating condition as the steady-state operating condition if the difference between the parameter information and the target information meets the set conditions includes:

[0017] If the absolute value of the first difference between the target average indicated pressure and the current average indicated pressure is less than a set threshold, and the absolute value of the second difference between the target intake volume and the current intake volume is within a set range, then the operating condition is determined to be the steady-state operating condition.

[0018] Optionally, determining the engine's operating conditions based on the parameter information includes:

[0019] If the parameter information satisfies the steady-state condition, then after the target duration, the correction coefficient within the set duration is obtained; the correction coefficient refers to the control coefficient when performing proportional-integral-derivative control on the air-fuel ratio.

[0020] If the change of the correction coefficient within the set time period is less than the set range, then the working condition is determined to be a steady-state condition.

[0021] Optionally, the target duration is determined in the following manner:

[0022] Obtain the actual air-fuel ratio and the desired air-fuel ratio of the vehicle;

[0023] The target duration is determined based on the ratio between the actual air-fuel ratio and the desired air-fuel ratio; the target duration is negatively correlated with the ratio.

[0024] Optionally, performing the carbon canister flushing operation includes:

[0025] The carbon canister solenoid valve controlling the vehicle is in the closed state;

[0026] Obtain the actual air-fuel ratio and the desired air-fuel ratio of the vehicle;

[0027] Based on the proportional-integral-derivative control method, the actual air-fuel ratio is adjusted to the air-fuel ratio range corresponding to the desired air-fuel ratio;

[0028] After the actual air-fuel ratio is within the specified air-fuel ratio range, the canister solenoid valve is opened to perform the canister flushing operation.

[0029] Optionally, the method further includes:

[0030] During the carbon canister flushing operation, the carbon canister oil-gas concentration and the target oil quantity required by the engine are obtained;

[0031] Based on the carbon canister oil and gas concentration, the first oil quantity corresponding to the carbon canister oil and gas is calculated;

[0032] Based on the target fuel quantity and the first fuel quantity, the second fuel quantity corresponding to the fuel injector of the vehicle is calculated;

[0033] The injector is controlled to inject fuel based on the second fuel quantity so that the engine operates at the target fuel quantity.

[0034] Secondly, embodiments of this application provide a control device for rinsing a carbon canister, comprising:

[0035] The first acquisition unit is used to acquire parameter information of the vehicle's engine;

[0036] The first operating condition determination unit is used to determine the operating condition of the engine based on the parameter information.

[0037] An execution unit is configured to perform a carbon canister flushing operation if the operating condition is a steady-state condition.

[0038] The stop unit is used to prevent the carbon canister flushing operation from being performed if the operating condition is dynamic.

[0039] Thirdly, embodiments of this application provide an on-board controller, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the control method for carbon canister flushing as described in any of the first aspects above.

[0040] Fourthly, embodiments of this application provide a computer-readable storage medium storing a computer program that, when executed by a processor, implements the control method for rinsing a carbon canister as described in any one of the first aspects above.

[0041] Fifthly, embodiments of this application provide a computer program product that, when run on an on-board controller, enables the on-board controller to execute the carbon canister flushing control method described in any of the first aspects above.

[0042] Sixthly, embodiments of this application provide a vehicle including an on-board controller for performing a control method for rinsing a carbon canister as described in any of the first aspects.

[0043] The beneficial effects of the embodiments of this application compared with the prior art are:

[0044] This application provides a control method for canister flushing, which involves acquiring engine parameter information of a vehicle; determining the engine's operating condition based on the parameter information; performing canister flushing if the operating condition is steady-state; and not performing canister flushing if the operating condition is dynamic. Compared with the prior art, this application performs canister flushing only when the engine is operating under steady-state conditions, making the canister fuel concentration determined during flushing more accurate. This solves the problem of unstable idling or even stalling during flushing caused by obtaining incorrect canister fuel concentrations, especially artificially high concentrations. Furthermore, the more accurate canister fuel concentration determined during flushing also avoids insufficient total fuel supply leading to a lean air-fuel ratio after combustion, which can cause unstable idling or even unstable engine combustion due to insufficient fuel. On the other hand, this application does not perform carbon canister flushing when the engine is operating under dynamic conditions, thus avoiding obtaining incorrect carbon canister oil and gas concentrations under dynamic conditions, and further avoiding problems such as unstable idling or even stalling during flushing due to incorrect carbon canister oil and gas concentrations. Attached Figure Description

[0045] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0046] Figure 1 This is a flowchart illustrating the implementation of a carbon canister flushing control method according to an embodiment of this application;

[0047] Figure 2 This is a flowchart illustrating the implementation of a control method for rinsing a carbon canister according to another embodiment of this application;

[0048] Figure 3 This is a flowchart illustrating the implementation of a control method for rinsing a carbon canister according to another embodiment of this application;

[0049] Figure 4 This is a flowchart illustrating the implementation of a control method for rinsing a carbon canister according to another embodiment of this application;

[0050] Figure 5 This is a flowchart illustrating the implementation of a control method for rinsing a carbon canister according to another embodiment of this application;

[0051] Figure 6 This is a schematic diagram of the structure of a control device for rinsing a carbon canister according to an embodiment of this application;

[0052] Figure 7This is a schematic diagram of the structure of an on-board controller provided in one embodiment of this application. Detailed Implementation

[0053] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0054] It should be understood that, when used in this application specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.

[0055] It should also be understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0056] As used in this application specification and the appended claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrase "if determined" or "if detected [the described condition or event]" may be interpreted, depending on the context, as meaning "once determined," "in response to determination," "once detected [the described condition or event]," or "in response to detection [the described condition or event]."

[0057] Furthermore, in the description of this application and the appended claims, the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0058] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0059] Currently, after fuel evaporates in the fuel tank, fuel vapors accumulate, increasing the tank pressure. To address this issue, the evaporated fuel vapors are introduced into a carbon canister with adsorption capabilities for storage. Later, during the carbon canister flushing process, fresh air from the external environment is used to clean it, allowing the flushing air and desorbed fuel from the canister to re-enter the engine for combustion, thus saving fuel and reducing fuel vapor emissions.

[0060] However, existing technologies may determine the carbon canister oil-gas concentration incorrectly when flushing the carbon canister under dynamic engine conditions. If the carbon canister oil-gas concentration is too high, insufficient fuel injection during carbon canister flushing under low-load idling conditions will lead to unstable idling or even engine stalling, while also affecting the flushing volume. If the carbon canister oil-gas concentration is too low, it will result in a richer air-fuel mixture under low-load engine conditions.

[0061] Specifically, when the carbon canister flushing is activated, the engine's total fuel demand consists of two parts: one part comes from the fuel injector, and the other part comes from the carbon canister fuel vapor. The amount of fuel in the carbon canister fuel vapor is calculated from the concentration of the carbon canister fuel vapor, which is learned by the engine ECU through proportional-integral-derivative control. The higher the carbon canister fuel vapor concentration learned by the engine ECU, the more fuel the engine ECU will think that the carbon canister fuel vapor can provide. If the total fuel demand is fixed, the amount of fuel allocated to the injector will be reduced. If the learned carbon canister fuel vapor concentration is too high, the actual total fuel quantity will be insufficient, the air-fuel ratio will be too lean after combustion, the idle speed will be unstable, or even unable to maintain stable combustion due to insufficient fuel, resulting in unstable idling or even inability to maintain idle speed.

[0062] Based on this, this application proposes a control method for carbon canister flushing to avoid engine idling instability or even stalling during carbon canister flushing.

[0063] Please see Figure 1 , Figure 1 This is a flowchart illustrating the implementation of a control method for rinsing a carbon canister according to an embodiment of this application. In this embodiment, the executing entity of the control method for rinsing a carbon canister is an on-board controller. The on-board controller may be an electronic control unit.

[0064] In practical applications, the Electronic Control Unit (ECU) is also known as the vehicle's computer or onboard computer. The ECU is essentially the brain of the car, responsible for controlling various functions and systems. The ECU collects sensor signals, processes them, and then issues control commands to instruct actuators. Its main functions include controlling the engine's fuel injection quantity, ignition timing, and variable valve timing to ensure efficient and stable engine operation.

[0065] likeFigure 1 As shown, the carbon canister flushing control method provided in one embodiment of this application may include S101 to S104, which are described in detail below:

[0066] In S101, obtain the parameter information of the vehicle's engine.

[0067] In practical applications, when relevant personnel need to perform carbon canister flushing on a vehicle, they can send a carbon canister flushing request to the vehicle controller.

[0068] In this embodiment, the vehicle controller detects the aforementioned carbon canister flushing request by detecting a preset operation for the vehicle. The preset operation can be set according to actual needs and is not limited here. For example, the preset operation may include clicking a preset control on the vehicle. Therefore, when the vehicle controller detects that a preset control on the vehicle has been clicked, it indicates that a preset operation has been detected, that is, the aforementioned carbon canister flushing request has been detected.

[0069] Because the carbon canister concentration obtained during carbon canister flushing under dynamic conditions is inaccurate, it can easily lead to unstable engine idling or even stalling when the carbon canister is flushed under low load at idle. Therefore, in this embodiment, after detecting the above-mentioned carbon canister flushing request, the vehicle controller needs to obtain the engine parameter information of the vehicle to determine the engine's operating conditions.

[0070] Dynamic operating conditions are used to describe operating conditions where the engine load is changing. For example, the process of the driver pressing the accelerator pedal and the required torque increasing, or the process of the driver releasing the accelerator pedal and the torque decreasing.

[0071] In this embodiment of the application, the parameter information includes, but is not limited to: the engine's average indicated pressure, intake volume, intake pressure, relative filling volume, and exhaust volume.

[0072] In practical applications, the mean indicated pressure (Pmi) is the indicated work done per unit cylinder working volume in one cycle of an engine. It reflects the utilization rate of the engine's cylinder working volume; the higher the Pmi, the better the engine's working cycle is performed, and the higher the utilization rate of the cylinder working volume.

[0073] Relative intake volume refers to the amount of air that actually enters the cylinder during the intake process of an engine. It is usually expressed as relative intake volume per stroke and can also be called intake efficiency.

[0074] In S102, the operating conditions of the engine are determined based on the parameter information.

[0075] In this embodiment of the application, after obtaining the engine parameter information, the vehicle controller can determine the engine's operating condition based on the parameter information.

[0076] The engine's operating conditions include, but are not limited to, steady-state conditions and dynamic conditions.

[0077] Steady-state operating condition describes a condition where the difference between the vehicle's actual air-fuel ratio and the desired air-fuel ratio is less than a set difference, indicating that the vehicle's fuel closed-loop control has been learned and stabilized. Both the desired air-fuel ratio and the set difference can be determined according to actual needs and are not restricted here.

[0078] It should be noted that the aforementioned fuel closed-loop control specifically refers to the on-board controller performing proportional-integral-derivative control (PID control) based on the air-fuel ratio measured by the vehicle's oxygen sensor and the desired air-fuel ratio, so as to make the measured air-fuel ratio reach the desired air-fuel ratio.

[0079] In one embodiment of this application, the vehicle controller can acquire the expected information corresponding to the parameter information and compare the parameter information with its corresponding expected information.

[0080] In this embodiment, when the on-board controller detects that the difference between the parameter information and the expected information is less than or equal to the set difference, it can determine that the engine is in a steady-state condition.

[0081] When the on-board controller detects that the difference between the parameter information and the expected information is greater than the set difference, it can determine that the engine is in a dynamic operating condition.

[0082] In one embodiment of this application, in order to improve the accuracy of determining the engine's operating conditions, the vehicle controller can specifically achieve the following: Figure 2 The steps S201 to S202 shown below determine the engine's operating conditions, which are detailed below:

[0083] In S201, the parameter information is filtered to obtain the target information.

[0084] In this embodiment, in order to determine whether the air-fuel ratio of the vehicle changes drastically and whether the engine is in a steady state, the vehicle controller can filter the acquired parameter information to obtain the target information corresponding to the parameter information.

[0085] In some possible embodiments, the above filtering method can be: first-order delay filtering, i.e., first-order hysteresis filtering.

[0086] In this embodiment, after obtaining the parameter information and its corresponding target information, the vehicle controller can determine the difference between the parameter information and its corresponding target information, and detect whether the difference meets the set conditions. The set conditions can be determined according to actual needs and are not limited here.

[0087] For example, the setting condition could be: the absolute value of the difference between the parameter information and the target information is less than a set threshold. The set threshold can be determined according to actual needs and is not limited here.

[0088] Another possible setting condition is that the absolute value of the difference between the parameter information and the target information is within a set range. The set range can be determined according to actual needs and is not limited here.

[0089] In one embodiment of this application, when the vehicle controller detects that the difference between the parameter information and the target information meets the set conditions, it can execute step S202.

[0090] In another embodiment of this application, when the vehicle controller detects that the difference between the parameter information and the target information does not meet the set conditions, it indicates that the air-fuel ratio of the vehicle is changing drastically and the engine is not working in a steady state. Therefore, the vehicle controller can determine that the engine is in a dynamic operating condition.

[0091] In other embodiments, since different parameter information corresponds to different filtering coefficients, in order to improve the filtering accuracy and filtering success rate, when the parameter information includes the current average indicated pressure and the current intake air volume, the vehicle controller can specifically implement step S201 according to the following steps, detailed below:

[0092] The target average indicated pressure is obtained by performing a first-order delay filter on the current average indicated pressure based on the first filter coefficient.

[0093] The target air intake volume is obtained by performing a first-order delay filter on the current air intake volume based on the second filter coefficient; the second filter coefficient is different from the first filter coefficient.

[0094] It should be noted that the aforementioned current average indicated pressure specifically refers to the average indicated pressure obtained by the engine controller within one control cycle. One control cycle can be determined according to actual needs and is not limited here; for example, one control cycle can be defined as 10ms.

[0095] The aforementioned current intake volume specifically refers to the intake volume obtained by the engine controller within one control cycle.

[0096] In this embodiment, the vehicle controller can perform first-order delay filtering on the current average indicated pressure based on a first filtering coefficient to obtain the target average indicated pressure; and perform first-order delay filtering on the current intake volume based on a second filtering coefficient to obtain the target intake volume. Both the first and second filtering coefficients can be determined according to actual needs and are not limited here.

[0097] It should be noted that the second filter coefficient is different from the first filter coefficient.

[0098] In this embodiment, after obtaining the target average indicated pressure and the target intake volume, the vehicle controller can calculate a first difference between the target average indicated pressure and the current average indicated pressure, and calculate a second difference between the target intake volume and the current intake volume. Then, the vehicle controller can detect whether the absolute value of the first difference is less than a set threshold, and detect whether the absolute value of the second difference is within a set range.

[0099] In S202, if the difference between the parameter information and the target information meets the set conditions, then the working condition is determined to be the steady-state working condition.

[0100] In this embodiment, when the vehicle controller detects that the difference between the parameter information and the target information meets the set conditions, it indicates that the air-fuel ratio of the vehicle is not changing drastically and the engine is working in a steady state. Therefore, the vehicle controller can determine that the engine is in a steady-state condition.

[0101] In one embodiment of this application, in conjunction with S201, when the parameter information includes the current average indicated pressure and the current intake air volume, in order to further improve the accuracy of determining whether the engine is in a steady-state operating condition, the vehicle controller may specifically perform the following steps, detailed below:

[0102] If the absolute value of the first difference between the target average indicated pressure and the current average indicated pressure is less than a set threshold, and the absolute value of the second difference between the target intake volume and the current intake volume is within a set range, then the operating condition is determined to be the steady-state operating condition.

[0103] In this embodiment, when the vehicle controller detects that the absolute value of the first difference is less than a set threshold and the absolute value of the second difference is within a set range, it can determine that the air-fuel ratio of the vehicle is not changing drastically and the engine is working in a steady state. Therefore, the vehicle controller can determine that the engine is in a steady-state condition.

[0104] In another embodiment of this application, when the vehicle controller detects that the absolute value of the first difference is greater than or equal to a set threshold, or that the absolute value of the second difference is not within a set range, it indicates that the air-fuel ratio of the vehicle is changing drastically and the engine is not operating in a steady state. Therefore, the vehicle controller can determine that the engine is in a dynamic operating condition.

[0105] In S103, if the working condition is a steady state, then the carbon canister flushing operation is performed.

[0106] In this embodiment of the application, when the vehicle controller detects that the engine is in a steady-state operating condition, it indicates that carbon canister flushing is to be performed at this time. The vehicle controller can learn the accurate carbon canister fuel-air concentration according to the fuel closed-loop control. Therefore, at this time, the vehicle controller can perform the carbon canister flushing operation.

[0107] It should be noted that the process of learning the carbon canister fuel concentration based on the fuel closed-loop control includes both an upward learning process and a downward learning process. Upward learning specifically refers to the carbon canister fuel concentration gradually increasing, while downward learning specifically refers to the carbon canister fuel concentration gradually decreasing.

[0108] The specific process of upward learning is as follows: When the carbon canister flushing begins (the carbon canister solenoid valve opens), the vehicle's oxygen sensor measures a richer air-fuel ratio (less than the target air-fuel ratio). At this time, the on-board controller determines that the richness is caused by the carbon canister fuel-air mixture being higher than the current fuel-air mixture concentration. Therefore, the carbon canister fuel-air mixture concentration begins to learn upward (Note: The total intake air volume and the target air-fuel ratio are known. The total fuel quantity = injection quantity + carbon canister fuel-air mixture quantity. If the actual air-fuel mixture is richer than the target air-fuel ratio during flushing, it is determined that the carbon canister fuel-air mixture provides more fuel than the current concentration calculates. Therefore, the actual concentration needs to be increased, which means learning upward to increase the concentration. This reduces the fuel-air mixture demand, thereby reducing the total fuel quantity so that the actual air-fuel ratio gradually approaches the target).

[0109] The specific process of downward learning is as follows: Carbon canister flushing begins (carbon canister solenoid valve opens), and the air-fuel ratio measured by the vehicle's oxygen sensor is lean (greater than the target air-fuel ratio). At this time, the on-board controller determines that the leanness is caused by the carbon canister fuel-air mixture being less than the current fuel-air mixture concentration. Therefore, the carbon canister fuel-air mixture concentration begins to learn downward (Note: The total intake air volume is known, the target air-fuel ratio is known, and the total fuel quantity = injection quantity + carbon canister fuel-air mixture quantity. If the actual air-fuel mixture is leaner than the target air-fuel ratio during flushing, it is determined that the carbon canister fuel-air mixture provides less fuel than the current concentration calculates. Therefore, the actual concentration needs to be reduced, that is, it learns downward to be smaller. Then, the fuel-air mixture demand can be increased to increase the total fuel quantity so that the actual air-fuel ratio gradually approaches the target).

[0110] In one embodiment of this application, to further improve the success rate of the carbon canister flushing operation, the vehicle controller may specifically be as follows: Figure 3 Steps S301 to S304 shown represent the carbon canister flushing operation, detailed below:

[0111] In S301, the carbon canister solenoid valve controlling the vehicle is in the closed state.

[0112] In S302, the actual air-fuel ratio and the desired air-fuel ratio of the vehicle are obtained.

[0113] In S303, based on the proportional-integral-derivative control method, the actual air-fuel ratio is adjusted to the air-fuel ratio range corresponding to the desired air-fuel ratio.

[0114] In S304, after the actual air-fuel ratio is within the air-fuel ratio range, the canister solenoid valve is opened to perform the canister flushing operation.

[0115] In this embodiment, after determining that the engine is in a steady-state operating condition, in order to further ensure that the accurate carbon canister fuel-air concentration can be learned based on fuel closed-loop control, the vehicle controller can keep the vehicle's carbon canister solenoid valve in the closed state. This allows the vehicle controller to subsequently adjust the engine's actual air-fuel ratio under various operating conditions to the desired air-fuel ratio range through fuel closed-loop control learning under this condition. Specifically, the actual air-fuel ratio refers to the air-fuel ratio measured by the oxygen sensor.

[0116] The lower limit of the above air-fuel ratio range = desired air-fuel ratio - change range, and the upper limit of the above air-fuel ratio range = desired air-fuel ratio + change range. The change range can be determined according to actual needs and is not limited here; for example, the change range can be 10%.

[0117] Then, the vehicle controller can adjust the actual air-fuel ratio to the range corresponding to the desired air-fuel ratio based on the proportional-integral-derivative control method.

[0118] In this embodiment, when the actual air-fuel ratio is adjusted to the air-fuel ratio range corresponding to the desired air-fuel ratio, the vehicle controller can learn the accurate carbon canister fuel-air concentration when the carbon canister solenoid valve is opened for carbon canister flushing. Therefore, the vehicle controller can open the carbon canister solenoid valve to perform the carbon canister flushing operation.

[0119] It should be noted that after the vehicle controller learns the accurate carbon canister fuel concentration, when the engine is operating under low load conditions such as idling, the amount of fuel from the carbon canister fuel can be accurately calculated, so that the total amount of fuel injection meets the engine's fuel requirements, and the exhaust air-fuel ratio after combustion is near the target air-fuel ratio, thus the engine can operate stably.

[0120] In S104, if the working condition is a dynamic condition, the carbon canister flushing operation is not performed.

[0121] It's important to note that when the canister is flushed under dynamic engine conditions, the fuel closed-loop control typically doesn't achieve a perfect match between the actual and target air-fuel ratios. If canister flushing is performed at this time, the vehicle controller will determine that the deviation between the actual and target air-fuel ratios is caused by the carbon canister fuel mixture. The controller will then learn a carbon canister fuel mixture concentration that deviates from the true value. If this learning continues under these conditions, the concentration may deviate significantly from the actual value, meaning the controller will learn an increasingly erroneous concentration, potentially leading to unstable engine idling or even stalling. Furthermore, if the engine is idling, and the vehicle is a hybrid with a high battery charge, the engine load is very low, and its anti-interference capability is weak. Continuing canister flushing under these conditions can cause the controller to inject too much or too little fuel, resulting in an excessively lean or rich air-fuel ratio after combustion. An excessively lean ratio, in particular, can cause unstable engine speeds or even stalling due to inability to maintain operation.

[0122] Therefore, in this embodiment of the application, when the vehicle controller detects that the engine is in a dynamic operating condition, it can output a prompt message to relevant personnel indicating that the vehicle cannot perform carbon canister flushing at this time, and does not perform carbon canister flushing operation on the vehicle.

[0123] As can be seen from the above, the carbon canister flushing control method provided in this application obtains the engine parameter information of the vehicle; determines the engine's operating condition based on the parameter information; if the operating condition is a steady-state condition, the carbon canister flushing operation is performed; if the operating condition is a dynamic condition, the carbon canister flushing operation is not performed. Compared with the prior art, on the one hand, this application only performs the carbon canister flushing operation when the engine is operating under a steady-state condition, making the carbon canister fuel-air concentration determined during carbon canister flushing more accurate, thereby solving the problem of unstable idling or even stalling during flushing caused by obtaining incorrect carbon canister fuel-air concentration, especially an artificially high carbon canister fuel-air concentration. At the same time, the more accurate carbon canister fuel-air concentration determined during carbon canister flushing also avoids insufficient total fuel supply to the engine leading to a lean air-fuel ratio after combustion, resulting in unstable idling or even unstable engine combustion due to insufficient fuel. On the other hand, this application does not perform carbon canister flushing when the engine is operating under dynamic conditions, thus avoiding obtaining incorrect carbon canister oil and gas concentrations under dynamic conditions, and further avoiding problems such as unstable idling or even stalling during flushing due to incorrect carbon canister oil and gas concentrations.

[0124] Please see Figure 4 , Figure 4 This is a flowchart illustrating the implementation of a carbon canister flushing control method according to another embodiment of this application. Relative to... Figure 1 In a corresponding embodiment, the control method for rinsing the carbon canister may further include S401 to S402, as detailed below:

[0125] In S401, if the parameter information satisfies the steady-state condition, then after the target duration, the correction coefficient within the set duration is obtained; the correction coefficient refers to the control coefficient when performing proportional-integral-derivative control on the air-fuel ratio.

[0126] In this embodiment, the parameter information satisfying the steady-state condition specifically means that the difference between the parameter information and its corresponding target information meets the set conditions.

[0127] It should be noted that the process of ensuring the difference between the above parameter information and its corresponding target information meets the set conditions is... Figure 2 The steps S201 to S202 in the corresponding embodiments are the same. Please refer to the relevant descriptions in steps S201 to S202 for details, which will not be repeated here.

[0128] In one embodiment of this application, the target duration can be determined according to the following steps, detailed below:

[0129] Obtain the actual air-fuel ratio and the desired air-fuel ratio of the vehicle;

[0130] The target duration is determined based on the ratio between the actual air-fuel ratio and the desired air-fuel ratio; the target duration is negatively correlated with the ratio.

[0131] In this embodiment, the vehicle controller can obtain the vehicle's actual air-fuel ratio in real time through the vehicle's oxygen sensor, which is wirelessly connected to it.

[0132] After obtaining the actual air-fuel ratio and the desired air-fuel ratio, the vehicle controller can determine the target duration based on the ratio between the actual and desired air-fuel ratios. The target duration is negatively correlated with this ratio.

[0133] It should be noted that the larger the ratio mentioned above, the shorter the target duration, and the smaller the ratio mentioned above, the longer the target duration.

[0134] In this embodiment, after the vehicle controller detects that the engine parameters meet the steady-state conditions, due to the delay in the actual air-fuel ratio performance of the vehicle, the vehicle needs to meet a certain delay time condition to accurately determine whether the engine is in a steady-state operating condition. Therefore, the vehicle controller needs to wait for a target duration.

[0135] After the target duration, in order to accurately determine whether the engine is in a steady-state operating condition, the vehicle controller can obtain a correction coefficient within the set duration. The set duration can be determined according to actual needs and is not limited here. For example, the set duration can be a unit of time, i.e., 1 second.

[0136] It should be noted that the correction coefficient refers to the control coefficient when performing proportional-integral-derivative control on the air-fuel ratio, that is, the coefficient corresponding to the fuel closed-loop control.

[0137] In this embodiment, the vehicle controller can calculate the change range of the correction coefficient within a set time period.

[0138] Specifically, the vehicle controller can construct a coefficient curve based on the correction coefficient at each moment within a set time period. Then, the vehicle controller can take any two points in the coefficient curve to calculate the slope corresponding to the coefficient curve, and determine the slope as the change range of the correction coefficient within the set time period.

[0139] The vehicle controller can then compare this change with a set range. The set range can be determined according to actual needs and is not limited here; for example, the set range could be 0.05.

[0140] In one embodiment of this application, when the vehicle controller detects that the change in the correction coefficient within a set time period is less than a set range, it may execute step S402.

[0141] In another embodiment of this application, when the vehicle controller detects that the change of the correction coefficient within a set time period is greater than or equal to the set range, it indicates that the change of the correction coefficient is large, that is, the change of the correction coefficient is large. Therefore, the vehicle controller can determine that the engine has not reached a stable state, that is, the engine is not in a steady state.

[0142] In S402, if the change of the correction coefficient within the set time period is less than the set range, then the working condition is determined to be a steady-state working condition.

[0143] In this embodiment, when the vehicle controller detects that the change in the correction coefficient within a set time period is less than the set range, it indicates that the change in the correction coefficient is small, that is, the change in the correction coefficient is small. Therefore, the vehicle controller can determine that the engine has reached a stable state, that is, the engine is in a steady-state operating condition.

[0144] As can be seen from the above, the carbon canister flushing control method provided in this embodiment can obtain a correction coefficient within a certain time after the engine parameter information meets the steady-state conditions, and then determine whether the engine is indeed in a steady-state condition based on the correction coefficient, thereby further improving the accuracy of the judgment on whether the engine is in a steady-state condition.

[0145] Please see Figure 5 , Figure 5 This is a flowchart illustrating the implementation of a carbon canister flushing control method provided in another embodiment of this application. Compared to... Figure 1In a corresponding embodiment, the control method for rinsing the carbon canister may further include S501 to S504, as detailed below:

[0146] In S501, during the carbon canister flushing operation, the carbon canister oil-gas concentration and the target oil quantity required by the engine are obtained.

[0147] In this embodiment, when the vehicle controller performs the carbon canister flushing operation, the carbon canister is flushed with fresh air from the external environment. This allows the flushing air and desorbed fuel from the carbon canister to re-enter the engine for combustion. In other words, the engine's total fuel demand consists of two parts: one part comes from the vehicle's fuel injectors, and the other part comes from the carbon canister fuel vapor. The amount of fuel in the carbon canister fuel vapor is calculated from the carbon canister fuel vapor concentration. Therefore, in this embodiment, to ensure stable engine operation at the required fuel quantity, the vehicle controller can obtain the carbon canister fuel vapor concentration and the engine's target fuel quantity.

[0148] In practical applications, the target amount of oil required by the engine is usually fixed.

[0149] In S502, the first oil quantity corresponding to the carbon canister oil and gas concentration is calculated.

[0150] In this embodiment, since the carbon canister flushing is performed when the engine is in a steady-state condition, the carbon canister oil and gas concentration obtained at this time is accurate. Therefore, the vehicle controller can calculate the first oil quantity corresponding to the carbon canister oil and gas based on the obtained carbon canister oil and gas concentration, that is, the amount of oil supplied by the carbon canister oil and gas to the engine.

[0151] In S503, the second fuel quantity corresponding to the fuel injector of the vehicle is calculated based on the target fuel quantity and the first fuel quantity.

[0152] In S504, the injector is controlled to inject fuel based on the second fuel quantity so that the engine operates at the target fuel quantity.

[0153] In this embodiment, after the vehicle controller calculates the accurate first fuel quantity, it can accurately calculate the second fuel quantity that the vehicle's injectors need to inject based on the target fuel quantity and the first fuel quantity.

[0154] Where the second fuel quantity = target fuel quantity - first fuel quantity.

[0155] Then, the on-board controller can control the injectors to inject fuel based on the second fuel quantity mentioned above, so that the engine can operate stably at the target fuel quantity.

[0156] As can be seen from the above, the carbon canister flushing control method provided in this embodiment performs the carbon canister flushing operation under steady-state engine conditions, which makes the carbon canister fuel concentration determined during carbon canister flushing more accurate. Therefore, a more accurate fuel quantity corresponding to the carbon canister fuel can be calculated, thereby accurately determining the amount of fuel to be injected by the injector. This allows the engine to operate at the actual target fuel quantity required, thus avoiding insufficient total fuel supply to the engine, resulting in a lean air-fuel ratio after combustion, unstable idling speed, and unstable engine combustion due to insufficient fuel.

[0157] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0158] Corresponding to the carbon canister flushing control method described in the above embodiments, Figure 6 A schematic diagram of a control device for rinsing a carbon canister according to an embodiment of this application is shown. For ease of explanation, only the parts relevant to the embodiment of this application are shown. (Refer to...) Figure 6 The control device 600 for rinsing the carbon canister includes: a first acquisition unit 61, a first operating condition determination unit 62, an execution unit 63, and a stop unit 64. Wherein:

[0159] The first acquisition unit 61 is used to acquire parameter information of the vehicle's engine.

[0160] The first operating condition determination unit 62 is used to determine the operating condition of the engine based on the parameter information.

[0161] The execution unit 63 is used to perform a carbon canister flushing operation if the working condition is a steady state.

[0162] The stop unit 64 is used to not perform the carbon canister flushing operation if the working condition is a dynamic working condition.

[0163] In one embodiment of this application, the first operating condition determination unit 62 specifically includes: a first processing unit and a second operating condition determination unit. Wherein:

[0164] The first processing unit is used to filter the parameter information to obtain the target information.

[0165] The second operating condition determination unit is used to determine the operating condition as the steady-state operating condition if the difference between the parameter information and the target information meets the set conditions.

[0166] In one embodiment of this application, the parameter information includes the current average indicated pressure and the current intake air volume; the first processing unit specifically includes a second processing unit and a third processing unit; correspondingly, the second operating condition determination unit specifically includes a third operating condition determination unit. Wherein:

[0167] The second processing unit is used to perform first-order delay filtering on the current average indicated pressure based on the first filtering coefficient to obtain the target average indicated pressure.

[0168] The third processing unit is used to perform first-order delay filtering on the current air intake based on the second filtering coefficient to obtain the target air intake; the second filtering coefficient is different from the first filtering coefficient.

[0169] The third operating condition determination unit is used to determine the operating condition as the steady-state operating condition if the absolute value of the first difference between the target average indicated pressure and the current average indicated pressure is less than a set threshold, and the absolute value of the second difference between the target intake volume and the current intake volume is within a set range.

[0170] In one embodiment of this application, the first operating condition determination unit 62 specifically includes: a second acquisition unit and a fourth operating condition determination unit. Wherein:

[0171] The second acquisition unit is used to acquire the correction coefficient within a set time period after the target time period if the parameter information meets the steady-state condition; the correction coefficient refers to the control coefficient when performing proportional-integral-derivative control on the air-fuel ratio.

[0172] The fourth operating condition determination unit is used to determine the operating condition as a steady-state condition if the change range of the correction coefficient within the set time period is less than the set range.

[0173] In one embodiment of this application, the control device 600 for carbon canister rinsing further includes: a third acquisition unit and a duration determination unit. Wherein:

[0174] The third acquisition unit is used to acquire the actual air-fuel ratio and the desired air-fuel ratio of the vehicle.

[0175] The duration determination unit is used to determine the target duration based on the ratio between the actual air-fuel ratio and the desired air-fuel ratio; the target duration is negatively correlated with the ratio.

[0176] In one embodiment of this application, the execution unit 63 specifically includes: a first control unit, a fourth acquisition unit, an adjustment unit, and an activation unit. Wherein:

[0177] The first control unit is used to control the carbon canister solenoid valve of the vehicle to be in the closed state.

[0178] The fourth acquisition unit is used to acquire the actual air-fuel ratio and the desired air-fuel ratio of the vehicle.

[0179] The adjustment unit is used to adjust the actual air-fuel ratio to the air-fuel ratio range corresponding to the desired air-fuel ratio based on the proportional-integral-derivative control method.

[0180] The opening unit is used to open the canister solenoid valve after the actual air-fuel ratio is within the air-fuel ratio range, so as to perform the canister flushing operation.

[0181] In one embodiment of this application, the control device 600 for rinsing the carbon canister further includes: a fifth acquisition unit, a first calculation unit, a second calculation unit, and a second control unit. Wherein:

[0182] The fifth acquisition unit is used to acquire the carbon canister oil-gas concentration and the target oil quantity required by the engine when performing the carbon canister flushing operation.

[0183] The first calculation unit is used to calculate the first oil quantity corresponding to the carbon canister oil and gas concentration.

[0184] The second calculation unit is used to calculate the second fuel quantity corresponding to the fuel injector of the vehicle based on the target fuel quantity and the first fuel quantity.

[0185] The second control unit is used to control the injector to inject fuel based on the second fuel quantity, so that the engine operates at the target fuel quantity.

[0186] It should be noted that the information interaction and execution process between the above-mentioned devices / units are based on the same concept as the method embodiments of this application. For details on their specific functions and technical effects, please refer to the method embodiments section, and they will not be repeated here.

[0187] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments 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 unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0188] Figure 7 This is a schematic diagram of the structure of an on-board controller provided in one embodiment of this application. Figure 7 As shown, the vehicle controller 7 of this embodiment includes: at least one processor 70 ( Figure 7 (Only one is shown in the diagram), memory 71, and computer program 72 stored in said memory 71 and executable on said at least one processor 70, wherein the processor 70 executes said computer program 72 to implement the steps in any of the above-described control method embodiments for rinsing carbon canisters.

[0189] The vehicle controller may include, but is not limited to, a processor 70 and a memory 71. Those skilled in the art will understand that... Figure 7 The vehicle controller 7 is merely an example and does not constitute a limitation on it. It may include more or fewer components than shown, or combine certain components, or different components, such as input / output devices, network access devices, etc.

[0190] The processor 70 may be a Central Processing Unit (CPU), or it may be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor.

[0191] In some embodiments, the memory 71 may be an internal storage unit of the vehicle controller 7, such as the RAM of the vehicle controller 7. In other embodiments, the memory 71 may be an external storage device of the vehicle controller 7, such as a plug-in hard drive, smart media card (SMC), secure digital (SD) card, flash card, etc., equipped on the vehicle controller 7. Furthermore, the memory 71 may include both internal storage units and external storage devices of the vehicle controller 7. The memory 71 is used to store the operating system, applications, bootloader, data, and other programs, such as the program code of the computer program. The memory 71 can also be used to temporarily store data that has been output or will be output.

[0192] This application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps described in the various method embodiments above.

[0193] This application provides a computer program product that, when run on an in-vehicle controller, enables the in-vehicle controller to perform the steps described in the above-described method embodiments.

[0194] 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, all or part of the processes in the methods of the above embodiments of this application can be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include at least: any entity or device capable of carrying the computer program code to the vehicle controller, a recording medium, a computer memory, a read-only memory (ROM), a random access memory (RAM), an electrical carrier signal, a telecommunication signal, and a software distribution medium. Examples include USB flash drives, portable hard drives, magnetic disks, or optical disks. In some jurisdictions, according to legislation and patent practice, computer-readable media cannot be electrical carrier signals or telecommunication signals.

[0195] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0196] The above-described 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, and should all be included within the protection scope of this application.

Claims

1. A control method of a carbon canister purge, characterized by, The method comprises: obtaining parameter information of an engine of a vehicle; determining a working condition of the engine based on the parameter information; if the working condition is a steady state condition, performing a carbon canister purge operation; if the working condition is a dynamic condition, not performing the carbon canister purge operation; the determining of the working condition of the engine based on the parameter information comprises: if the parameter information satisfies a steady state condition, obtaining a correction coefficient within a set time period after a target time period; the correction coefficient refers to a control coefficient when performing proportional-integral-derivative control on an air-fuel ratio; if a variation amplitude of the correction coefficient within the set time period is less than a set amplitude, determining that the working condition is a steady state condition; the target time period is determined according to the following manner: obtaining an actual air-fuel ratio and an expected air-fuel ratio of the vehicle; determining the target time period based on a ratio between the actual air-fuel ratio and the expected air-fuel ratio; the target time period is negatively correlated with the ratio. the performing of the carbon canister purge operation comprises:

2. The control method of carbon can purge according to claim 1, wherein, controlling a carbon canister electromagnetic valve of the vehicle to be in a closed state; obtaining an actual air-fuel ratio and an expected air-fuel ratio of the vehicle; adjusting the actual air-fuel ratio to an air-fuel ratio range corresponding to the expected air-fuel ratio based on a proportional-integral-derivative control manner; after the actual air-fuel ratio is in the air-fuel ratio range, opening the carbon canister electromagnetic valve to perform the carbon canister purge operation. The method further comprises:

3. A method of controlling the purging of a carbon canister according to any one of claims 1-2, characterized in that, when performing the carbon canister purge operation, obtaining a carbon canister oil gas concentration and a target oil amount required by the engine; based on the carbon canister oil gas concentration, calculating a first oil amount corresponding to the carbon canister oil gas; based on the target oil amount and the first oil amount, calculating a second oil amount corresponding to an injector of the vehicle; controlling the injector to inject based on the second oil amount, so that the engine works at the target oil amount. The method comprises:

4. A control device for carbon canister purging, characterized by, a first obtaining unit configured to obtain parameter information of an engine of a vehicle; a first working condition determining unit configured to determine a working condition of the engine based on the parameter information; an executing unit configured to, if the working condition is a steady state condition, perform a carbon canister purge operation; a stopping unit configured to, if the working condition is a dynamic condition, not perform the carbon canister purge operation; the first working condition determining unit specifically comprises: a second obtaining unit configured to, if the parameter information satisfies a steady state condition, obtain a correction coefficient within a set time period after a target time period; the correction coefficient refers to a control coefficient when performing proportional-integral-derivative control on an air-fuel ratio; a fourth working condition determining unit configured to, if a variation amplitude of the correction coefficient within the set time period is less than a set amplitude, determine that the working condition is a steady state condition; the control device for the carbon canister purge further comprises: a third obtaining unit configured to obtain an actual air-fuel ratio and an expected air-fuel ratio of the vehicle; a time period determining unit configured to determine the target time period based on a ratio between the actual air-fuel ratio and the expected air-fuel ratio; the target time period is negatively correlated with the ratio. The processor implements the control method for the carbon canister purge when executing the computer program.

5. An in-vehicle controller comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, The vehicle-mounted controller comprises the vehicle-mounted controller according to claim 5.

6. A vehicle characterized by comprising: ​

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