Carbon tank aging diagnosis method and device, vehicle and storage medium

Abstract

The invention provides a carbon tank aging diagnosis method and device, a vehicle and a storage medium, and the method comprises the steps: determining a first theoretical fuel oil vapor adsorption amount of a carbon tank according to the fuel oil basic evaporation amount and evaporation time of fuel oil; when a preset carbon tank desorption condition is met, the carbon tank is controlled to execute desorption operation; in the process that the carbon tank executes desorption operation, the actual fuel steam desorption amount of the carbon tank is determined according to the desorption flow of the carbon tank, the air flow of a throttle valve, the fuel injection amount and the actual air-fuel ratio; and determining a carbon tank aging diagnosis result according to a comparison result of the first theoretical fuel oil steam adsorption amount and the actual fuel oil steam desorption amount. As whether the carbon tank is aged or not is diagnosed, a user can know the aging condition of the carbon tank in time, so that the aged carbon tank can be maintained or replaced in time, and the problem that the emission of evaporative pollutants of a vehicle exceeds the standard is avoided to a certain extent.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and in particular to a method, device, vehicle, and storage medium for diagnosing carbon canister aging. Background Art

[0002] The activated carbon in the carbon canister typically adsorbs and stores fuel vapor evaporating from the fuel tank. When the engine is started, the canister solenoid valve may open. The negative pressure generated in the intake manifold draws the fuel vapor stored in the canister into the engine for combustion (a process known as desorption), thereby reducing evaporative pollutant emissions.

[0003] In order to prevent leakage of fuel vapor, in related technologies, the on-board self-diagnostic system monitors the desorption flow of the fuel evaporation system and the integrity of the entire fuel evaporation system except for the pipes and joints between the carbon canister valve and the intake manifold, thereby ensuring the normal operation of the fuel evaporation system.

[0004] However, this method does not monitor the aging of the carbon canister. When the carbon canister ages, its ability to adsorb and desorb fuel vapor is generally weakened, potentially leading to an inability to effectively adsorb and desorb fuel vapor, which in turn may cause the vehicle's evaporative pollutant emissions to exceed the standard.

[0005] It should be pointed out that the information disclosed in the background technology section of this application is only intended to deepen the understanding of the general background technology of this application, and should not be regarded as an admission or any form of implication that the information constitutes prior art already known to those skilled in the art. Summary of the Invention

[0006] The present application provides a carbon canister aging diagnosis method, device, vehicle and storage medium, so as to solve the problem in the related art that the evaporative pollutant emissions of the vehicle may exceed the standard due to the failure to monitor whether the carbon canister is aging.

[0007] In a first aspect, an embodiment of the present application provides a method for diagnosing carbon canister aging, comprising: determining a first theoretical fuel vapor adsorption amount of the carbon canister based on a basic fuel evaporation amount and an evaporation time of the fuel, wherein the basic fuel evaporation amount is used to characterize a volatility of the fuel; When a preset carbon canister desorption condition is met, controlling the carbon canister to perform a desorption operation, wherein the desorption operation is used to release the fuel vapor adsorbed by the carbon canister into the engine; During the desorption operation of the carbon canister, an actual fuel vapor desorption amount of the carbon canister is determined based on the desorption flow rate of the carbon canister, the throttle air flow rate, the fuel injection amount, and the actual air-fuel ratio, wherein the desorption flow rate is the mass of air and fuel vapor delivered by the carbon canister to the engine, the throttle air flow rate is the mass of air entering the engine through the throttle, the fuel injection amount is the amount of fuel delivered by the injector to the engine, and the actual air-fuel ratio is the actual ratio of air to fuel when the engine is in operation; A carbon canister aging diagnosis result is determined based on a comparison result of the first theoretical fuel vapor adsorption amount and the actual fuel vapor desorption amount.

[0008] In a possible implementation, the carbon canister desorption condition includes: the first theoretical fuel vapor adsorption amount is greater than a preset first fuel vapor adsorption amount threshold and the engine operating water temperature is greater than or equal to a preset operating water temperature threshold.

[0009] In one possible implementation, determining the actual fuel vapor desorption amount of the carbon canister based on the desorption flow rate of the carbon canister, the throttle air flow rate, the fuel injection amount, and the actual air-fuel ratio includes: determining an actual fuel vapor desorption amount corresponding to the current desorption time based on a desorption flow rate of the carbon canister corresponding to the current desorption time, a throttle air flow rate, a fuel injection amount, and an actual air-fuel ratio; performing cumulative calculation on an actual fuel vapor desorption amount corresponding to the current desorption time and an actual fuel vapor desorption amount corresponding to a historical desorption time to determine a cumulative fuel vapor desorption amount corresponding to the current desorption time; performing a subtraction operation on the first theoretical fuel vapor adsorption amount and the accumulated fuel vapor desorption amount to determine a current remaining fuel vapor adsorption amount of the carbon canister; When the current remaining fuel vapor adsorption amount is less than a preset second fuel vapor adsorption amount threshold, the actual fuel vapor desorption amount of the carbon canister is determined to be the accumulated fuel vapor desorption amount.

[0010] In one possible implementation, the desorption flow of the carbon canister corresponding to the current desorption time is determined based on the effective opening of the carbon canister solenoid valve and the gas flow rate corresponding to the current desorption time, and the gas flow rate is used to characterize the flow rate of air and fuel vapor delivered by the carbon canister to the engine.

[0011] In one possible implementation, determining the carbon canister aging diagnosis result according to the comparison result of the first theoretical fuel vapor adsorption amount and the actual fuel vapor desorption amount includes: A carbon canister aging diagnosis result is determined based on a comparison result of the first theoretical fuel vapor adsorption amount and a fuel vapor adsorption amount difference, wherein the fuel vapor adsorption amount difference is the difference between the actual fuel vapor desorption amount and the second theoretical fuel vapor adsorption amount, and the second theoretical fuel vapor adsorption amount is the amount of fuel vapor in the fuel tank adsorbed onto the carbon canister during the desorption process.

[0012] In one possible implementation, determining the carbon canister aging diagnosis result based on the comparison result between the first theoretical fuel vapor adsorption amount and the difference between the fuel vapor adsorption amounts includes: determining a current carbon canister adsorption capacity coefficient based on the first theoretical fuel vapor adsorption amount and a difference between the fuel vapor adsorption amount; performing a weighted calculation on the current carbon canister adsorption capacity coefficient and the historical carbon canister adsorption capacity coefficient, and comparing the calculation result with a preset carbon canister adsorption capacity coefficient threshold to determine a carbon canister aging diagnosis result; The current carbon canister adsorption capacity coefficient is used to characterize the ability of the carbon canister to adsorb fuel vapor in the current carbon canister aging diagnosis, and the historical carbon canister adsorption capacity coefficient is used to characterize the ability of the carbon canister to adsorb fuel vapor in the historical carbon canister aging diagnosis.

[0013] In one possible implementation, determining the carbon canister aging diagnosis result according to the comparison result of the first theoretical fuel vapor adsorption amount and the actual fuel vapor desorption amount includes: When any one of the preset carbon canister aging diagnosis interruption conditions does not occur, a carbon canister aging diagnosis result is determined based on a comparison result of the first theoretical fuel vapor adsorption amount and the actual fuel vapor desorption amount.

[0014] In a second aspect, an embodiment of the present application provides a carbon canister aging diagnostic device, comprising: a fuel vapor adsorption amount determination module, configured to determine a first theoretical fuel vapor adsorption amount of the carbon canister based on a basic fuel evaporation amount and an evaporation time of the fuel, wherein the basic fuel evaporation amount is used to represent a volatility of the fuel; a desorption operation execution module, configured to control the carbon canister to execute a desorption operation when a preset carbon canister desorption condition is met, wherein the desorption operation is configured to release the fuel vapor adsorbed by the carbon canister into the engine; a fuel vapor desorption amount determination module, configured to determine an actual fuel vapor desorption amount of the carbon canister during a desorption operation of the carbon canister based on a desorption flow rate of the carbon canister, a throttle air flow rate, a fuel injection amount, and an actual air-fuel ratio, wherein the desorption flow rate is the mass of air and fuel vapor delivered by the carbon canister to the engine, the throttle air flow rate is the mass of air entering the engine through the throttle, the fuel injection amount is the amount of fuel delivered by the injector to the engine, and the actual air-fuel ratio is the actual ratio of air to fuel when the engine is operating; The carbon canister aging diagnosis result determination module is configured to determine a carbon canister aging diagnosis result based on a comparison result between the first theoretical fuel vapor adsorption amount and the actual fuel vapor desorption amount.

[0015] In a third aspect, an embodiment of the present application provides a vehicle, comprising: A controller is configured to execute the method according to any one of the first aspects.

[0016] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method described in any one of the first aspects is implemented.

[0017] In the embodiment of the present application, a first theoretical fuel vapor adsorption capacity of the carbon canister is first determined based on the basic evaporation capacity and evaporation time of the fuel. Then, the actual fuel vapor desorption capacity of the carbon canister during the desorption process, i.e., the actual fuel vapor adsorption capacity, is determined based on the desorption flow rate of the carbon canister, the throttle air flow rate, the fuel injection amount, and the actual air-fuel ratio. Finally, a carbon canister aging diagnosis result is determined based on the comparison between the first theoretical fuel vapor adsorption capacity and the actual fuel vapor desorption capacity. This diagnosis of carbon canister aging allows users to promptly understand the aging status of the carbon canister, allowing them to promptly repair or replace the aged carbon canister, thereby, to a certain extent, avoiding the problem of excessive evaporative pollutant emissions from the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0019] Figure 1 A schematic diagram of the connection relationship between a carbon canister, a fuel tank and an engine provided in an embodiment of the present application.

[0020] Figure 2A flowchart of a carbon canister aging diagnosis method provided in an embodiment of the present application.

[0021] Figure 3 A flowchart of another carbon canister aging diagnosis method provided in an embodiment of the present application.

[0022] Figure 4 A flowchart of another carbon canister aging diagnosis method provided in an embodiment of the present application.

[0023] Figure 5 A flowchart of another carbon canister aging diagnosis method provided in an embodiment of the present application.

[0024] Figure 6 A schematic structural diagram of a carbon canister aging diagnostic device provided in an embodiment of the present application.

[0025] Figure 7 A schematic structural diagram of a vehicle provided in an embodiment of the present application. DETAILED DESCRIPTION

[0026] In order to better understand the technical solution of the present application, the embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0027] It should be clear that the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0028] The terms used in the embodiments of the present application are for the purpose of describing specific embodiments only and are not intended to limit the present application. The singular forms "a", "an", "the" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise.

[0029] It should be understood that the term "and / or" as used herein simply describes a relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A alone, A and B together, or B alone. Furthermore, the character " / " in this document generally indicates an "or" relationship between the associated objects.

[0030] See also Figure 1 , is a schematic diagram of the connection relationship between a carbon canister, a fuel tank and an engine provided in an embodiment of the present application. Figure 1Figure 1 shows a fuel tank 101, a carbon canister 102, and an engine 103. The fuel in the fuel tank 101 is generally volatile. To prevent the direct release of volatile fuel vapor into the atmosphere, which could cause environmental pollution, a carbon canister 102 containing activated carbon can be connected to the fuel tank 101 via a first interface. The activated carbon in the carbon canister 102 is generally capable of adsorbing and storing fuel vapor volatilized from the fuel tank.

[0031] In one possible implementation, the carbon canister 102 is connected to a carbon canister solenoid valve via a second interface, and the carbon canister solenoid valve is connected to the engine 103 via the intake manifold. It is understood that when the engine is started, the carbon canister solenoid valve may be opened. At this time, the negative pressure generated by the intake manifold can draw air from the atmosphere into the carbon canister 102. This flowing air can carry the fuel vapor in the carbon canister 102 through the carbon canister solenoid valve and the intake manifold into the engine 103 for combustion (i.e., a desorption process), thereby reducing evaporative pollutant emissions.

[0032] In addition, when the engine is started, the fuel in the fuel tank 101 and the air in the atmospheric environment usually enter the engine through the injector and the throttle valve respectively to participate in combustion.

[0033] It should be pointed out that Figure 1 What is shown is merely an exemplary description and should not be regarded as limiting the scope of protection of this application.

[0034] In order to prevent leakage of fuel vapor, in related technologies, the on-board self-diagnostic system monitors the desorption flow of the fuel evaporation system and the integrity of the entire fuel evaporation system except for the pipes and joints between the carbon canister valve and the intake manifold, thereby ensuring the normal operation of the fuel evaporation system.

[0035] However, this method does not monitor the aging of the carbon canister. When the carbon canister ages, its ability to adsorb and desorb fuel vapor is generally weakened, potentially leading to an inability to effectively adsorb and desorb fuel vapor, which in turn may cause the vehicle's evaporative pollutant emissions to exceed the standard.

[0036] To address the above issues, in an embodiment of the present application, a first theoretical fuel vapor adsorption capacity of the carbon canister is first determined based on the basic evaporation rate and evaporation time of the fuel. Then, the actual fuel vapor desorption capacity of the carbon canister during the desorption process, i.e., the actual fuel vapor adsorption capacity, is determined based on the desorption flow rate of the carbon canister, the throttle air flow rate, the fuel injection rate, and the actual air-fuel ratio. Finally, a carbon canister aging diagnosis result is determined based on the comparison between the first theoretical fuel vapor adsorption capacity and the actual fuel vapor desorption capacity. This diagnosis of carbon canister aging allows users to promptly understand the aging status of the carbon canister, allowing them to promptly repair or replace the aged carbon canister, thus, to a certain extent, avoiding the problem of excessive evaporative pollutant emissions from the vehicle.

[0037] Specifically, a detailed description is given below with reference to the accompanying drawings and specific embodiments.

[0038] See also Figure 2 , is a flow chart of a carbon canister aging diagnosis method provided in an embodiment of the present application. Figure 2 As shown, the method specifically includes the following steps.

[0039] Step S201: determining a first theoretical fuel vapor adsorption amount of the carbon canister according to the basic fuel evaporation amount and evaporation time of the fuel.

[0040] The basic fuel evaporation rate (BEV) is used to characterize the volatility of the fuel. It is understood that BEV generally refers to the mass of fuel vapor naturally evaporated from the fuel in the tank over a certain period of time, which is primarily determined by the volatility of the fuel itself. The evaporation time starts at the moment after the last carbon canister purge process is completed, and ends at the moment the current carbon canister purge process begins. For example, if the moment after the last carbon canister purge process is t1 and the moment the current carbon canister purge process begins is t2, then the evaporation time is t2-t1.

[0041] In this embodiment of the present application, after determining the basic evaporation amount and evaporation time of the fuel, the first theoretical fuel vapor adsorption amount can be determined according to the formula: First Theoretical Fuel Vapor Adsorption Amount = Basic Fuel Vapor Adsorption Amount × Evaporation Time. To distinguish it from other theoretical fuel vapor adsorption amounts described below, in this embodiment of the present application, the theoretical fuel vapor adsorption amount determined before the carbon canister begins desorption is referred to as the "first theoretical fuel vapor adsorption amount."

[0042] It can be understood that the first theoretical fuel vapor adsorption amount can be considered as the amount of fuel vapor that the carbon canister can theoretically adsorb within the evaporation time.

[0043] However, the volatility of fuel itself may be affected by factors that influence fuel evaporation, such as ambient temperature, altitude, and humidity. Higher ambient temperatures typically increase the thermal motion of fuel molecules, resulting in more volatile fuel vapor. Higher altitudes lower atmospheric pressure, which generally reduces the resistance to fuel molecules escaping the fuel surface and increases volatile fuel vapor. Higher ambient humidity increases the amount of water in the air, raising the partial pressure of water vapor, which generally reduces the space available for fuel molecules to escape the fuel surface and reduces volatile fuel vapor.

[0044] Therefore, if the influence of fuel evaporation factors on the volatility characteristics of fuel is not considered, the basic evaporation amount of fuel may be too high or too low, making the first theoretical fuel vapor adsorption amount too high or too low, which may lead to low accuracy of the diagnosis results of carbon canister aging.

[0045] In a possible implementation, the first theoretical fuel vapor adsorption amount of the carbon canister may be determined according to the basic evaporation amount of the fuel, the evaporation time, and the fuel evaporation influencing factor.

[0046] Specifically, the first theoretical fuel vapor adsorption amount can be determined according to the formula: First theoretical fuel vapor adsorption amount = Basic fuel evaporation amount of the fuel × Evaporation time × Fuel evaporation influence factor. The fuel evaporation influence factor includes, but is not limited to, an ambient temperature factor, an altitude factor, and / or an ambient humidity factor. Of course, the fuel evaporation influence factor may also include a fuel level fluctuation amplitude correction factor, etc., which is not specifically limited in this embodiment of the present application.

[0047] It should be noted that the fuel evaporation influencing factors can be obtained through detection or calculation, and for the sake of brevity, the embodiments of the present application will not be described in detail here.

[0048] In the embodiment of the present application, by correcting the basic fuel evaporation amount by the fuel evaporation influence factor, a more accurate first theoretical fuel vapor adsorption amount can be obtained, which improves the accuracy of the carbon canister aging diagnosis result to a certain extent.

[0049] Step S202: When the preset carbon canister desorption condition is met, the carbon canister is controlled to perform a desorption operation.

[0050] To confirm the diagnosis of carbon canister aging, after determining the first theoretical fuel vapor adsorption amount of the carbon canister, it is also necessary to determine the actual fuel vapor adsorption amount of the carbon canister. Furthermore, based on the first theoretical fuel vapor adsorption amount and the actual fuel vapor adsorption amount of the carbon canister, whether the carbon canister has been diagnosed is determined.

[0051] In the embodiment of the present application, in order to determine the actual amount of fuel vapor adsorbed by the carbon canister, it is necessary to control the carbon canister to perform a desorption operation. It is understood that the desorption operation is used to release the fuel vapor adsorbed by the carbon canister into the engine. During the desorption operation, the actual amount of fuel vapor desorbed from the carbon canister, i.e., the actual amount of fuel vapor adsorbed by the carbon canister, can be determined. The specific details of "determining the actual amount of fuel vapor desorbed from the carbon canister" are described in detail below and will not be repeated here.

[0052] As mentioned above, the purpose of the carbon canister desorption operation is to release the fuel vapor stored in the carbon canister into the engine. Therefore, before controlling the carbon canister to perform the desorption operation, the engine needs to be started.

[0053] In addition, in order to make the engine run in a stable working state, in one possible implementation, the carbon canister desorption conditions include: the first theoretical fuel vapor adsorption amount is greater than the preset first fuel vapor adsorption amount threshold and the engine operating water temperature is greater than or equal to the preset operating water temperature threshold.

[0054] It can be understood that when the first theoretical fuel vapor adsorption amount exceeds the preset first fuel vapor adsorption amount threshold, it can be considered that the carbon canister has adsorbed a sufficient amount of fuel vapor. In this case, controlling the carbon canister to perform a desorption operation can reduce the frequency of engine starts, reduce engine wear to a certain extent, and thus extend engine life.

[0055] It should be noted that the first fuel vapor adsorption threshold is a preset value. Those skilled in the art can set a different first fuel vapor adsorption threshold based on actual needs. This embodiment of the present application does not impose any specific limitations on this. Furthermore, to distinguish it from other fuel vapor adsorption thresholds described below, in this embodiment of the present application, the fuel vapor adsorption threshold used to determine whether to perform a canister purge operation is referred to as the "first fuel vapor adsorption threshold."

[0056] In practice, when the engine's operating water temperature falls below the threshold, the engine may not be operating optimally and may not be able to accurately control the air-fuel ratio in the mixture. In this case, controlling the carbon canister to perform desorption may increase the fuel ratio in the engine mixture, resulting in incomplete fuel combustion and, in turn, a higher level of pollutants (such as nitrogen oxides and carbon monoxide) in the vehicle's exhaust emissions.

[0057] In this embodiment of the present application, when the engine operating water temperature is greater than or equal to a preset operating water temperature threshold, the engine is considered to be in optimal operating condition. At this point, the carbon canister is controlled to perform a purge operation, allowing the fuel vapor in the canister to fully mix with the air and burn, thereby reducing the pollutant content in the vehicle's exhaust gas to a certain extent.

[0058] Step S203: During the desorption operation of the carbon canister, the actual fuel vapor desorption amount of the carbon canister is determined according to the desorption flow rate of the carbon canister, the throttle air flow rate, the fuel injection amount and the actual air-fuel ratio.

[0059] Among them, the desorption flow rate is the mass of air and fuel vapor delivered by the carbon canister to the engine. It can be understood that, if Figure 1 As shown, when the engine is started and the canister solenoid valve is opened, the air drawn into the canister 102 can carry the fuel vapor in the canister 102 through the canister solenoid valve and the intake manifold into the engine 103 to participate in combustion. At this time, the air and fuel vapor passing through the canister solenoid valve can be considered as the desorption flow.

[0060] Furthermore, when the engine is started, the fuel in the fuel tank 101 and the air in the atmosphere typically enter the engine through the fuel injector and the throttle valve, respectively, to participate in combustion. Therefore, in the present embodiment, the throttle air flow rate refers to the mass of air entering the engine through the throttle valve, and the fuel injection rate refers to the amount of fuel delivered to the engine by the fuel injector.

[0061] In the present embodiment, the actual air-fuel ratio refers to the actual ratio of air to fuel during engine operation. It can be understood that the actual air-fuel ratio is the ratio of air and fuel involved in combustion within the engine when the canister is performing a purge operation. In this case, the air within the engine comes from air delivered through the canister solenoid valve and air delivered through the throttle; the fuel within the engine comes from fuel vapor delivered through the canister solenoid valve and fuel delivered through the injector.

[0062] In practice, it typically takes some time for the carbon canister to complete its desorption operation. Therefore, the actual amount of fuel vapor desorbed from the carbon canister can be determined by the desorption flow rate, throttle air flow rate, fuel injection amount, actual air-fuel ratio, and the total duration of the carbon canister desorption. However, during the carbon canister desorption operation, the desorption flow rate, throttle air flow rate, fuel injection amount, and actual air-fuel ratio may vary at different desorption times due to the vehicle's varying operating conditions.

[0063] In this case, if the actual amount of fuel vapor desorbed from the carbon canister during the entire desorption process is determined solely by using fixed desorption flow rate, throttle air flow rate, fuel injection amount, and actual air-fuel ratio, this fixed amount cannot reflect the desorption flow rate, throttle air flow rate, fuel injection amount, and actual air-fuel ratio at each desorption time during the entire desorption process. Therefore, the actual amount of fuel vapor desorbed during the entire desorption process may be less accurate, which in turn may lead to less accurate diagnosis results of carbon canister aging.

[0064] See also Figure 3 , is a flow chart of another carbon canister aging diagnosis method provided in an embodiment of the present application. Figure 3 As shown, the embodiment of the present application is Figure 2 Based on the illustrated embodiment, step S203 specifically includes steps S301 to S304.

[0065] Step S301: determining the actual fuel vapor desorption amount corresponding to the current desorption time according to the desorption flow rate of the carbon canister corresponding to the current desorption time, the throttle air flow rate, the fuel injection amount and the actual air-fuel ratio.

[0066] In the embodiment of the present application, after the carbon canister begins to perform the carbon canister operation, the actual fuel vapor desorption amount corresponding to each time period is determined according to a preset time period. It is understood that when determining the actual fuel vapor desorption amount corresponding to each time period, the time period can be considered to be the current desorption time. Furthermore, the actual fuel vapor desorption amount corresponding to the current desorption time can be determined based on the carbon canister desorption flow rate, throttle air flow rate, fuel injection amount, and actual air-fuel ratio corresponding to the current desorption time.

[0067] Among them, the desorption flow rate of the carbon canister corresponding to the current desorption time is the mass of air and fuel vapor delivered by the carbon canister to the engine during the current desorption time; the throttle air flow rate corresponding to the current desorption time is the mass of air entering the engine through the throttle during the current desorption time; the fuel injection amount corresponding to the current desorption time is the amount of fuel delivered by the injector to the engine during the current desorption time; the actual air-fuel ratio corresponding to the current desorption time is the actual ratio of air to fuel under the engine working state during the current desorption time.

[0068] It can be understood that when the carbon canister is performing the desorption operation, the desorption flow rate M corresponding to the current desorption time is 脱附流量 The air flow M delivered by the carbon canister solenoid valve during the current desorption time is included 电磁阀空气流量 and the fuel vapor amount G 燃油蒸气量 The total amount of air in the engine M 空气总量 =M 电磁阀空气流量 + Air flow M entering the engine through the throttle during the current desorption time 节气门空气流量 . Due to M 电磁阀空气流量 =M 脱附流量 -G 燃油蒸气量 , therefore, M 空气总量 =M 电磁阀空气流量 +M 脱附流量 -G 燃油蒸气量 In addition, the total amount of fuel in the engine G 燃油总量 =G 燃油蒸气量 +The amount of fuel delivered to the engine through the injector during the current desorption time G 喷油量 .

[0069] As mentioned above, the actual air-fuel ratio AF corresponding to the current desorption time is the actual ratio of air to fuel under the engine working state during the current desorption time, that is, AF=M 空气总量 / G 燃油总量 Therefore, G 燃油总量 =M 空气总量 / AF.

[0070] In other words, G 燃油蒸气量 +G 喷油量 =(M 电磁阀空气流量 +M 脱附流量 -G 燃油蒸气量 ) / AF. In the embodiment of the present application, after determining the desorption flow rate of the carbon canister, the throttle air flow rate, the fuel injection amount, and the actual air-fuel ratio corresponding to the current desorption time, the actual fuel vapor desorption amount corresponding to the current desorption time can be calculated according to the above formula, that is, G 燃油蒸气量 .

[0071] It should be noted that the above formula may also include other correction factors. Those skilled in the art may develop other formulas to determine the actual fuel vapor desorption amount corresponding to the current desorption time, and this embodiment of the present application does not impose any specific limitations. Furthermore, the throttle air flow, fuel injection amount, and actual air-fuel ratio corresponding to the current desorption time can all be obtained through detection or calculation, but for the sake of brevity, this embodiment of the present application does not provide a detailed description here.

[0072] In the embodiment of the present application, the desorption flow rate of the carbon canister corresponding to the current desorption time may be determined based on the effective opening of the carbon canister solenoid valve and the gas flow rate corresponding to the current desorption time.

[0073] Specifically, according to the formula: M 脱附流量 = C × V × T × η, which determines the canister desorption flow rate corresponding to the current desorption time. Where C is the effective opening of the canister solenoid valve corresponding to the current desorption time; V is the gas flow rate; T is the current desorption time; and η is the efficiency coefficient of the fuel evaporation system, including the canister, which is usually set by factoring in efficiency losses such as the flow resistance of the fuel evaporation system.

[0074] As you can understand, gas flow rate represents the flow rate of air and fuel vapor delivered from the canister to the engine. As mentioned above, when the canister delivers air and fuel vapor to the engine, it typically does so by utilizing the pressure differential across the canister solenoid valve. Therefore, different pressure differentials across the canister solenoid valve result in different gas flow rates.

[0075] In the embodiment of the present application, the gas flow rate corresponding to the current desorption time can be determined based on the pressure difference across the carbon canister solenoid valve corresponding to the current desorption time, using the corresponding relationship between the pressure difference across the carbon canister solenoid valve and the gas flow rate. This allows the desorption flow rate of the carbon canister corresponding to the current desorption time to be determined. Of course, those skilled in the art may develop other formulas to determine the desorption flow rate of the carbon canister corresponding to the current desorption time, and this embodiment of the present application does not impose any specific limitations.

[0076] Step S302: performing cumulative calculation on the actual fuel vapor desorption amount corresponding to the current desorption time and the actual fuel vapor desorption amount corresponding to the historical desorption time to determine the cumulative fuel vapor desorption amount corresponding to the current desorption time.

[0077] In the embodiment of the present application, the historical desorption time includes all time periods after the carbon canister is desorbed and the desorption operation is performed, and before the current desorption time. For example, if the current desorption time is the first time period after the carbon canister is desorbed and the desorption operation is performed, the historical desorption time is zero; if the current desorption time is the second time period after the carbon canister is desorbed and the desorption operation is performed, the historical desorption time includes the first time period; if the current desorption time is the third time period after the carbon canister is desorbed and the desorption operation is performed, the historical desorption time includes the first time period and the second time period; and so on, and this embodiment of the present application will not be repeated.

[0078] It is understood that the actual fuel vapor desorption amount corresponding to the historical desorption time includes the actual fuel vapor desorption amount corresponding to each time period in the historical desorption time. The determination of the actual fuel vapor desorption amount corresponding to each time period can be found in the description of step S301. For the sake of brevity, this embodiment of the present application will not be further described here.

[0079] In an embodiment of the present application, after determining the actual fuel vapor desorption amount corresponding to the current desorption time, it is necessary to perform accumulation calculation on the actual fuel vapor desorption amount corresponding to the historical desorption time to determine the accumulated fuel vapor desorption amount corresponding to the current desorption time.

[0080] For example, if the current desorption time is the first time period after the canister is desorbed and the desorption operation is performed, since there is no historical desorption time, the accumulated fuel vapor desorption amount corresponding to the current desorption time is the actual fuel vapor desorption amount corresponding to the first time period. If the current desorption time is the second time period after the canister is desorbed and the desorption operation is performed, and the historical desorption time includes the first time period, the accumulated fuel vapor desorption amount corresponding to the current desorption time is the actual fuel vapor desorption amount corresponding to the first time period + the actual fuel vapor desorption amount corresponding to the second time period. If the current desorption time is the third time period after the canister is desorbed and the historical desorption time includes the first and second time periods, the accumulated fuel vapor desorption amount corresponding to the current desorption time is the actual fuel vapor desorption amount corresponding to the first time period + the actual fuel vapor desorption amount corresponding to the second time period + the actual fuel vapor desorption amount corresponding to the third time period; and so on, and the embodiments of the present application are not specifically limited by comparison.

[0081] Step S303: performing a subtraction operation on the first theoretical fuel vapor adsorption amount and the accumulated fuel vapor desorption amount to determine the current remaining fuel vapor adsorption amount of the carbon canister.

[0082] In this embodiment of the present application, the remaining fuel vapor adsorption amount in the carbon canister can be used to determine whether the fuel vapor adsorbed in the carbon canister has been completely delivered to the engine. Since it is unknown within which the carbon canister completes the desorption operation, after determining the accumulated fuel vapor desorption amount corresponding to the current desorption time, the first theoretical fuel vapor adsorption amount and the accumulated fuel vapor desorption amount can be subtracted to determine the current remaining fuel vapor adsorption amount in the carbon canister. Furthermore, the current remaining fuel vapor adsorption amount can be used to determine whether the carbon canister has completed the desorption operation within the current desorption time.

[0083] Step S304: When the current remaining fuel vapor adsorption amount is less than a preset second fuel vapor adsorption amount threshold, determining the actual fuel vapor desorption amount of the carbon canister as the accumulated fuel vapor desorption amount.

[0084] In order to distinguish it from the first fuel vapor adsorption amount threshold mentioned above, in the embodiment of the present application, the fuel vapor adsorption amount threshold used to determine whether the carbon canister has completed the desorption operation is referred to as the "second fuel vapor adsorption amount threshold".

[0085] It can be understood that when the current remaining fuel vapor adsorption amount is less than the preset second fuel vapor adsorption amount threshold, it can be assumed that the fuel vapor adsorbed in the carbon canister has been almost completely delivered to the engine during the current desorption time, that is, the carbon canister has completed the desorption operation. In this case, the actual fuel vapor desorption amount of the carbon canister can be determined as the accumulated fuel vapor desorption amount corresponding to the current desorption time.

[0086] It should be noted that the second fuel vapor adsorption threshold is a preset value and is lower than the first fuel vapor adsorption threshold. Those skilled in the art will be able to set a different second fuel vapor adsorption threshold based on actual needs. This embodiment of the present application does not impose any specific limitations on this.

[0087] In this embodiment of the present application, the actual fuel vapor desorption amount corresponding to each time period during the desorption process is calculated in real time based on the canister's desorption flow rate, throttle air flow rate, fuel injection amount, and actual air-fuel ratio. This allows for a more accurate determination of the actual fuel vapor desorption amount. This more accurate actual fuel vapor desorption amount enables a more precise diagnosis of canister aging.

[0088] Step S204: Determine a carbon canister aging diagnosis result based on a comparison result of the first theoretical fuel vapor adsorption amount and the actual fuel vapor desorption amount.

[0089] In actual applications, if the first theoretical fuel vapor adsorption amount is greater than the actual fuel vapor desorption amount, the carbon canister can be considered to have aged. However, during the carbon canister's desorption process, the fuel in the tank will still volatilize. At this time, the activated carbon in the carbon canister adsorbs this volatilized fuel vapor. Therefore, the desorbed fuel vapor may include fuel vapor that volatilized during the desorption process, which may lead to errors in the actual fuel vapor desorption amount. Furthermore, based on the inaccurate actual fuel vapor desorption amount, the diagnostic results of carbon canister aging may be less accurate.

[0090] See also Figure 4 , is a flow chart of another carbon canister aging diagnosis method provided in an embodiment of the present application. Figure 4 As shown, the embodiment of the present application is Figure 2 Based on the illustrated embodiment, step S204 specifically includes step S401.

[0091] Step S401: determining a carbon canister aging diagnosis result based on a comparison result of the first theoretical fuel vapor adsorption amount and the fuel vapor adsorption amount difference.

[0092] The fuel vapor adsorption amount difference is the difference between the actual fuel vapor desorption amount and the second theoretical fuel vapor adsorption amount. To distinguish it from the other theoretical fuel vapor adsorption amounts mentioned above, in this embodiment of the application, the theoretical fuel vapor adsorption amount determined during the canister's desorption operation is referred to as the "second theoretical fuel vapor adsorption amount."

[0093] It is understood that the second theoretical fuel vapor adsorption amount is the amount of fuel vapor adsorbed onto the carbon canister during the desorption process of the fuel in the fuel tank. In this embodiment of the present application, the second theoretical fuel vapor adsorption amount is determined based on the basic fuel evaporation amount, the desorption time of the carbon canister, and the fuel evaporation influencing factor.

[0094] The desorption time starts at the time when the carbon canister begins to desorb, and ends at the time when the carbon canister completes the desorption operation. For example, if the carbon canister starts to desorb at t3 and completes at t4, the desorption time is t4-t3.

[0095] Specifically, the formula: Second theoretical fuel vapor adsorption amount = basic fuel evaporation amount × desorption time × fuel evaporation impact factor. This formula can be used to determine a more accurate second theoretical fuel vapor adsorption amount. Based on this more accurate second theoretical fuel vapor adsorption amount, a more accurate actual fuel vapor desorption amount can be determined, thereby improving the accuracy of canister aging diagnosis results to a certain extent.

[0096] For other contents involved in the embodiment of the present application, please refer to the description in step S201. For the sake of brevity, the embodiment of the present application will not be repeated here.

[0097] In the embodiment of the present application, after determining the first theoretical fuel vapor adsorption amount and the fuel vapor adsorption amount difference, it is necessary to compare the first theoretical fuel vapor adsorption amount and the fuel vapor adsorption amount difference to determine whether the carbon canister is aged.

[0098] Theoretically, if the difference between the first theoretical fuel vapor adsorption amount and the fuel vapor adsorption amount is equal to or similar to each other, it can be considered that the amount of fuel vapor that the carbon canister can theoretically adsorb is equal to or similar to the amount of fuel vapor that it can actually adsorb, that is, the carbon canister can be considered not to have aged.

[0099] Therefore, in a possible implementation, if the carbon canister adsorption capacity coefficient of the carbon canister is less than a preset carbon canister adsorption capacity coefficient threshold, it is determined that the carbon canister is aged.

[0100] The carbon canister adsorption capacity coefficient is the ratio of the difference in fuel vapor adsorption to the first theoretical fuel vapor adsorption capacity. The carbon canister adsorption capacity coefficient indicates the canister's ability to adsorb fuel vapor. When the canister adsorption capacity coefficient is less than a threshold, the canister is considered aged.

[0101] It should be noted that those skilled in the art can also determine the aging result of the carbon canister by the difference between the fuel vapor adsorption amount and the first theoretical fuel vapor adsorption amount.

[0102] In addition, the carbon canister adsorption capacity coefficient threshold is a preset value. In the embodiment of the present application, the vehicle manufacturer can conduct evaporative emission tests on carbon canisters of different aging degrees to determine the carbon canister adsorption capacity coefficient threshold.

[0103] Specifically, when the emission result is close to the evaporative emission limit, the carbon canister with the corresponding aging degree of the emission result can be determined to be a critical carbon canister, and the ratio of the adsorption capacity of the critical carbon canister to the maximum adsorption capacity of the normal carbon canister is determined as the carbon canister adsorption capacity coefficient threshold.

[0104] In actual application, the aging of the carbon canister is a slow and long-lasting process. Therefore, there may be a certain degree of randomness in diagnosing whether the carbon canister is aged based only on the first theoretical fuel vapor adsorption amount and the difference in fuel vapor adsorption amount in the current carbon canister aging diagnosis.

[0105] See also Figure 5 , is a flow chart of another carbon canister aging diagnosis method provided by the embodiment of the present application. As shown in the figure, the embodiment of the present application Figure 4 Based on the illustrated embodiment, step S401 specifically includes steps S501 and S502.

[0106] Step S501: Determine the current carbon canister adsorption capacity coefficient according to the first theoretical fuel vapor adsorption amount and the difference between the fuel vapor adsorption amount.

[0107] It is understood that the current carbon canister adsorption capacity coefficient is used to represent the carbon canister's ability to adsorb fuel vapor during the current carbon canister aging diagnosis. In the embodiment of the present application, the current carbon canister adsorption capacity coefficient is the ratio of the fuel vapor adsorption amount difference to the first theoretical fuel vapor adsorption amount.

[0108] Step S502: performing a weighted calculation on the current carbon canister adsorption capacity coefficient and the historical carbon canister adsorption capacity coefficient, and comparing the calculation result with a preset carbon canister adsorption capacity coefficient threshold to determine the carbon canister aging diagnosis result.

[0109] In the embodiment of the present application, the historical carbon canister adsorption capacity coefficient is used to characterize the carbon canister's ability to adsorb fuel vapor in the historical carbon canister aging diagnosis. It is understandable that the historical carbon canister aging diagnosis is the diagnosis process before the current carbon canister aging diagnosis.

[0110] For example, when the vehicle has undergone three carbon canister aging diagnoses, if the current carbon canister aging diagnosis is the first carbon canister aging diagnosis, the historical carbon canister adsorption capacity coefficient is zero; when the vehicle has undergone two carbon canister aging diagnoses, if the current carbon canister aging diagnosis is the second carbon canister aging diagnosis, the historical carbon canister adsorption capacity coefficient is the carbon canister adsorption capacity coefficient of the first carbon canister aging diagnosis (referred to as the "first carbon canister adsorption capacity coefficient"); when the vehicle has undergone three carbon canister aging diagnoses, if the current carbon canister aging diagnosis is the third carbon canister aging diagnosis, the historical carbon canister adsorption capacity coefficient is the carbon canister adsorption capacity coefficient of the first carbon canister aging diagnosis and the carbon canister adsorption capacity coefficient of the second carbon canister aging diagnosis (referred to as the "second carbon canister adsorption capacity coefficient"); and so on, and the embodiments of the present application will not be repeated.

[0111] In the embodiment of the present application, the controller typically stores historical carbon canister adsorption capacity coefficients in a storage module. Therefore, after determining the current carbon canister adsorption capacity coefficient, the controller can retrieve the historical carbon canister adsorption capacity coefficients from the storage module and then perform a weighted calculation on the current and historical carbon canister adsorption capacity coefficients to obtain a calculation result.

[0112] In a possible implementation, a weighted operation may be performed on the current carbon canister adsorption capacity coefficient and the historical carbon canister adsorption capacity coefficient, and an average value may be calculated to obtain an operation result.

[0113] For example, if the current carbon canister aging diagnosis is the second carbon canister aging diagnosis, the calculation result is (first carbon canister adsorption capacity coefficient × the weight corresponding to the first carbon canister adsorption capacity coefficient + current carbon canister adsorption capacity coefficient × the weight corresponding to the current carbon canister adsorption capacity coefficient) / 2; if the current carbon canister aging diagnosis is the third carbon canister aging diagnosis, the calculation result is (first carbon canister adsorption capacity coefficient × the weight corresponding to the first carbon canister adsorption capacity coefficient + second carbon canister adsorption capacity coefficient × the weight corresponding to the second carbon canister adsorption capacity coefficient + current carbon canister adsorption capacity coefficient × the weight corresponding to the current carbon canister adsorption capacity coefficient) / 3; and so on, the embodiments of the present application will not be repeated.

[0114] The weight associated with the current carbon canister adsorption capacity coefficient is higher than the weight associated with the historical carbon canister adsorption capacity coefficient. The current carbon canister adsorption capacity coefficient is the adsorption capacity of the carbon canister determined by the most recent carbon canister aging diagnosis during its use, and best reflects the degree of canister aging. Therefore, a higher weight can be assigned to the current carbon canister adsorption capacity coefficient.

[0115] As described above, after determining the result of the weighted calculation of the current carbon canister adsorption capacity coefficient and the historical carbon canister adsorption capacity coefficient, it is also necessary to compare the calculation result with the preset carbon canister adsorption capacity coefficient threshold to determine the carbon canister aging diagnosis result.

[0116] In the embodiment of the present application, when the calculation result is less than the preset carbon canister adsorption capacity coefficient threshold, the carbon canister aging diagnosis result is determined to be carbon canister aging and a carbon canister aging prompt message is output.

[0117] It is understood that when the calculation result is less than the preset carbon canister adsorption capacity coefficient threshold, it can be considered that the amount of fuel vapor that the carbon canister can theoretically adsorb and the amount of fuel vapor that can actually be adsorbed are not equal or similar. Therefore, it can be determined that the carbon canister is aged.

[0118] In addition, when the carbon canister is determined to be aged, a carbon canister aging prompt message is output to notify the user to repair or replace the carbon canister in time to avoid the problem of excessive evaporative pollutant emissions due to the aging of the carbon canister.

[0119] It should be noted that in the embodiment of the present application, the carbon canister aging prompt information can be output by outputting a fault code, voice broadcast, or warning light, etc. Of course, those skilled in the art can also output the carbon canister aging prompt information in other ways, and the embodiment of the present application does not specifically limit this.

[0120] In the embodiment of the present application, whether the carbon canister is aged is diagnosed based on the calculation results of the current carbon canister adsorption capacity coefficient and the historical carbon canister adsorption capacity coefficient, which improves the accuracy of the carbon canister aging diagnosis result to a certain extent.

[0121] In practice, the carbon canister aging diagnosis may be interrupted during the carbon canister desorption process, potentially preventing the canister from completing the desorption process. For example, this could be due to a malfunction in a component of the fuel evaporation system or the fuel system related to the canister desorption process, or a vehicle power outage (i.e., disconnecting the power supply after parking, putting the vehicle into a dormant state to stop consuming electricity). In these cases, it may be impossible to accurately determine the actual amount of fuel vapor desorbed, and, consequently, the carbon canister aging diagnosis may be impossible.

[0122] Therefore, in one possible implementation, during the desorption operation of the carbon canister, when any of the preset carbon canister aging diagnosis interruption conditions does not occur, the carbon canister aging diagnosis result is determined based on the comparison result of the first theoretical fuel vapor adsorption amount and the actual fuel vapor desorption amount.

[0123] Among them, the carbon canister aging diagnosis interruption conditions include failure of components or systems related to the carbon canister's desorption operation, the ambient temperature is not within the preset ambient temperature range, the altitude is not within the preset altitude range, the ambient humidity is not within the preset ambient humidity range, and the vehicle is powered off.

[0124] It is understood that during the carbon canister's desorption operation, if a component or system related to the carbon canister's desorption operation fails, the carbon canister may not be able to continue the desorption operation. When the ambient temperature is not within the preset ambient temperature range and / or the altitude is not within the preset altitude range and / or the ambient humidity is not within the preset ambient humidity range, the engine operating conditions may not be at optimal operating conditions. To ensure engine efficiency, the carbon canister solenoid valve may not be opened, and the carbon canister may not be able to continue the desorption operation. When the vehicle is powered off, the carbon canister may not be able to continue the desorption operation due to the vehicle being disconnected from the power supply.

[0125] In this embodiment of the present application, the canister aging diagnosis process is monitored during the canister desorption operation to ensure the accuracy of the actual fuel vapor desorption amount of the canister. If any of the canister aging diagnosis interruption conditions does not occur, the canister aging diagnosis result is determined based on a comparison between the first theoretical fuel vapor adsorption amount and the more accurate actual fuel vapor desorption amount. In other words, if any of the canister aging diagnosis interruption conditions occurs, the canister aging diagnosis step is discontinued.

[0126] In addition, when the vehicle is a hybrid vehicle and is running in pure electric mode, the engine is not running. In this case, the carbon canister solenoid valve is not open, and the fuel vapor in the carbon canister may not be transported to the engine. In other words, the carbon canister cannot be desorbed, and thus the carbon canister aging diagnosis cannot be performed.

[0127] Therefore, in the embodiment of the present application, when the vehicle is a hybrid vehicle, the carbon canister aging diagnosis interruption condition also includes the vehicle's driving mode being a pure electric mode.

[0128] In an embodiment of the present application, during the desorption operation of the carbon canister, whether any of the carbon canister aging diagnosis interruption conditions occurs is detected to determine whether to continue the current carbon canister aging diagnosis, thereby ensuring the accuracy of the carbon canister aging diagnosis to a certain extent.

[0129] In the embodiment of the present application, a first theoretical fuel vapor adsorption capacity of the carbon canister is first determined based on the basic evaporation capacity and evaporation time of the fuel. Then, the actual fuel vapor desorption capacity of the carbon canister during the desorption process, i.e., the actual fuel vapor adsorption capacity, is determined based on the desorption flow rate of the carbon canister, the throttle air flow rate, the fuel injection amount, and the actual air-fuel ratio. Finally, a carbon canister aging diagnosis result is determined based on the comparison between the first theoretical fuel vapor adsorption capacity and the actual fuel vapor desorption capacity. This diagnosis of carbon canister aging allows users to promptly understand the aging status of the carbon canister, allowing them to promptly repair or replace the aged carbon canister, thereby, to a certain extent, avoiding the problem of excessive evaporative pollutant emissions from the vehicle.

[0130] Corresponding to the above embodiment, the embodiment of the present application further provides a carbon canister aging diagnosis device.

[0131] See also Figure 6 , is a schematic diagram of the structure of a carbon canister aging diagnostic device provided in an embodiment of the present application. Figure 6 As shown, the carbon canister aging diagnosis device 600 includes a fuel vapor adsorption amount determination module 601 , a desorption operation execution module 602 , a fuel vapor desorption amount determination module 603 and a carbon canister aging diagnosis result determination module 604 .

[0132] Specifically, the fuel vapor adsorption amount determination module 601 is used to determine a first theoretical fuel vapor adsorption amount of the carbon canister based on the basic fuel evaporation amount and evaporation time of the fuel. The basic fuel evaporation amount is used to indicate the degree of volatility of the fuel. The desorption operation execution module 602 is used to control the carbon canister to perform a desorption operation when a preset carbon canister desorption condition is met. The desorption operation is used to release the fuel vapor adsorbed in the carbon canister into the engine. The fuel vapor desorption amount determination module 603 is used to determine the actual fuel vapor desorption amount of the carbon canister based on the carbon canister desorption flow rate, throttle air flow rate, fuel injection amount, and actual air-fuel ratio during the carbon canister desorption operation. The desorption flow rate is the mass of air and fuel vapor delivered by the carbon canister to the engine, the throttle air flow rate is the mass of air entering the engine through the throttle valve, the fuel injection amount is the amount of fuel delivered by the injector to the engine, and the actual air-fuel ratio is the actual ratio of air to fuel when the engine is operating. The carbon canister aging diagnosis result determination module 604 is used to determine the carbon canister aging diagnosis result based on a comparison result of the first theoretical fuel vapor adsorption amount and the actual fuel vapor desorption amount.

[0133] The specific contents involved in the embodiments of this application can be found in the description of the above method embodiments. For the sake of brevity, they will not be repeated here.

[0134] Corresponding to the above embodiment, an embodiment of the present application also provides a vehicle.

[0135] See also Figure 7 , is a schematic diagram of the structure of a vehicle provided in an embodiment of the present application. Figure 7 As shown, the vehicle 700 includes a controller 701 , which is configured to execute the above method embodiments.

[0136] Corresponding to the above embodiment, embodiments of the present application further provide a computer-readable storage medium, wherein the computer-readable storage medium may store a program. When the program is executed, the program may control the device containing the computer-readable storage medium to execute some or all of the steps of the above method embodiments. In a specific implementation, the computer-readable storage medium may be a magnetic disk, an optical disk, a read-only memory (ROM), or a random access memory (RAM).

[0137] In the embodiments of the present application, "at least one" refers to one or more, and "more" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent the existence of A alone, the existence of A and B at the same time, and the existence of B alone. Among them, A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following" and similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b and c can be represented by: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or multiple.

[0138] Those skilled in the art will appreciate that the various units and algorithm steps described in the embodiments disclosed herein can be implemented using a combination of electronic hardware, computer software, and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0139] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0140] In the several embodiments provided in this application, if any function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, or the part that contributes to the existing technology, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each embodiment of this application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, and other media that can store program code.

[0141] The above description is merely a specific embodiment of the present application. Any person skilled in the art may easily conceive of variations or substitutions within the technical scope disclosed in this application, and such variations or substitutions shall be within the scope of protection of this application. The scope of protection of this application shall be subject to the scope of protection of the claims.

Claims

1. A method for diagnosing carbon canister aging, characterized in that: include: determining a first theoretical fuel vapor adsorption amount of the carbon canister based on a basic fuel evaporation amount and an evaporation time of the fuel, wherein the basic fuel evaporation amount is used to characterize a volatility of the fuel; When a preset carbon canister desorption condition is met, controlling the carbon canister to perform a desorption operation, wherein the desorption operation is used to release the fuel vapor adsorbed by the carbon canister into the engine; During the desorption operation of the carbon canister, an actual fuel vapor desorption amount of the carbon canister is determined based on the desorption flow rate of the carbon canister, the throttle air flow rate, the fuel injection amount, and the actual air-fuel ratio, wherein the desorption flow rate is the mass of air and fuel vapor delivered by the carbon canister to the engine, the throttle air flow rate is the mass of air entering the engine through the throttle, the fuel injection amount is the amount of fuel delivered by the injector to the engine, and the actual air-fuel ratio is the actual ratio of air to fuel when the engine is in operation; A carbon canister aging diagnosis result is determined based on a comparison result of the first theoretical fuel vapor adsorption amount and the actual fuel vapor desorption amount.

2. The method according to claim 1, characterized in that The carbon canister desorption condition includes: the first theoretical fuel vapor adsorption amount is greater than a preset first fuel vapor adsorption amount threshold and the engine operating water temperature is greater than or equal to a preset operating water temperature threshold.

3. The method according to claim 1, characterized in that The determining the actual fuel vapor desorption amount of the carbon canister according to the desorption flow rate of the carbon canister, the throttle air flow rate, the fuel injection amount, and the actual air-fuel ratio includes: determining an actual fuel vapor desorption amount corresponding to the current desorption time based on a desorption flow rate of the carbon canister corresponding to the current desorption time, a throttle air flow rate, a fuel injection amount, and an actual air-fuel ratio; performing cumulative calculation on the actual fuel vapor desorption amount corresponding to the current desorption time and the actual fuel vapor desorption amount corresponding to the historical desorption time to determine the cumulative fuel vapor desorption amount corresponding to the current desorption time; performing a subtraction operation on the first theoretical fuel vapor adsorption amount and the accumulated fuel vapor desorption amount to determine a current remaining fuel vapor adsorption amount of the carbon canister; When the current remaining fuel vapor adsorption amount is less than a preset second fuel vapor adsorption amount threshold, the actual fuel vapor desorption amount of the carbon canister is determined to be the accumulated fuel vapor desorption amount.

4. The method according to claim 3, characterized in that Based on the effective opening of the carbon canister solenoid valve and the gas flow rate corresponding to the current desorption time, the desorption flow of the carbon canister corresponding to the current desorption time is determined, and the gas flow rate is used to characterize the flow rate of air and fuel vapor delivered by the carbon canister to the engine.

5. The method according to claim 1, wherein The determining of the carbon canister aging diagnosis result based on the comparison result of the first theoretical fuel vapor adsorption amount and the actual fuel vapor desorption amount includes: A carbon canister aging diagnosis result is determined based on a comparison result of the first theoretical fuel vapor adsorption amount and a fuel vapor adsorption amount difference, wherein the fuel vapor adsorption amount difference is the difference between the actual fuel vapor desorption amount and the second theoretical fuel vapor adsorption amount, and the second theoretical fuel vapor adsorption amount is the amount of fuel vapor in the fuel tank adsorbed onto the carbon canister during the desorption process.

6. The method according to claim 5, characterized in that The determining of the carbon canister aging diagnosis result based on the comparison result of the first theoretical fuel vapor adsorption amount and the difference between the fuel vapor adsorption amounts includes: determining a current carbon canister adsorption capacity coefficient based on the first theoretical fuel vapor adsorption amount and a difference between the fuel vapor adsorption amount; performing a weighted calculation on the current carbon canister adsorption capacity coefficient and the historical carbon canister adsorption capacity coefficient, and comparing the calculation result with a preset carbon canister adsorption capacity coefficient threshold to determine a carbon canister aging diagnosis result; The current carbon canister adsorption capacity coefficient is used to characterize the ability of the carbon canister to adsorb fuel vapor in the current carbon canister aging diagnosis, and the historical carbon canister adsorption capacity coefficient is used to characterize the ability of the carbon canister to adsorb fuel vapor in the historical carbon canister aging diagnosis.

7. The method according to claim 1, characterized in that The determining of the carbon canister aging diagnosis result based on the comparison result of the first theoretical fuel vapor adsorption amount and the actual fuel vapor desorption amount includes: When any one of the preset carbon canister aging diagnosis interruption conditions does not occur, a carbon canister aging diagnosis result is determined based on a comparison result of the first theoretical fuel vapor adsorption amount and the actual fuel vapor desorption amount.

8. A carbon canister aging diagnostic device, characterized in that: include: a fuel vapor adsorption amount determination module, configured to determine a first theoretical fuel vapor adsorption amount of the carbon canister based on a basic fuel evaporation amount and an evaporation time of the fuel, wherein the basic fuel evaporation amount is used to represent a volatility of the fuel; a desorption operation execution module, configured to control the carbon canister to execute a desorption operation when a preset carbon canister desorption condition is met, wherein the desorption operation is configured to release the fuel vapor adsorbed by the carbon canister into the engine; a fuel vapor desorption amount determination module, configured to determine an actual fuel vapor desorption amount of the carbon canister during a desorption operation of the carbon canister based on a desorption flow rate of the carbon canister, a throttle air flow rate, a fuel injection amount, and an actual air-fuel ratio, wherein the desorption flow rate is the mass of air and fuel vapor delivered by the carbon canister to the engine, the throttle air flow rate is the mass of air entering the engine through the throttle, the fuel injection amount is the amount of fuel delivered by the injector to the engine, and the actual air-fuel ratio is the actual ratio of air to fuel when the engine is operating; The carbon canister aging diagnosis result determination module is configured to determine a carbon canister aging diagnosis result based on a comparison result between the first theoretical fuel vapor adsorption amount and the actual fuel vapor desorption amount.

9. A vehicle, characterized in that: include: A controller configured to execute the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.

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