Method and system for diagnosing canister solenoid valve and vehicle

Abstract

The invention provides a method and system for diagnosing a canister solenoid valve and a vehicle. A system for diagnosing a canister solenoid valve may include a barometric pressure sensor and an engine control unit. The air pressure sensor may be coupled between the canister and the canister solenoid valve and may be configured to measure air pressure in the conduit between the canister and the canister solenoid valve. The engine control unit can be electrically connected to the carbon tank electromagnetic valve and the air pressure sensor respectively and can be configured to transmit an instruction for instructing the carbon tank electromagnetic valve to be opened or closed to the carbon tank electromagnetic valve and receive measured air pressure from the air pressure sensor. And the measured air pressure is compared with a corresponding valve opening threshold value or a valve closing threshold value to diagnose the carbon tank electromagnetic valve. The carbon tank solenoid valve diagnosis system can measure the air pressure in the pipeline and compare the measured air pressure with the corresponding valve opening threshold value or valve closing threshold value to diagnose the carbon tank solenoid valve.

Description

Technical Field

[0001] The present disclosure relates to the technical field of vehicle fault diagnosis, and in particular to a method, a system and a vehicle for diagnosing a carbon canister solenoid valve. Background Art

[0002] The vehicle's carbon canister and carbon canister solenoid valve are part of the vehicle's fuel evaporation control system. The carbon canister solenoid valve is installed on the vehicle to control the fuel vapor in the carbon canister, reduce air pollution caused by fuel evaporation emissions, and increase fuel efficiency. When the combustion engine starts working, the carbon canister solenoid valve can be switched to the open state so that the negative pressure in the intake system can suck the fuel vapor in the carbon canister. In some cases, the carbon canister solenoid valve may not be able to close completely due to certain reasons (such as valve sticking, etc.). This may cause additional air to enter the engine, resulting in an unexpected air-fuel mixture. In some other cases, the carbon canister solenoid valve may be unable to open the valve due to certain reasons, which may cause the fuel vapor to be unable to be sucked out of the carbon canister, resulting in emission problems.

[0003] Therefore, it is urgently desired to provide a method for diagnosing various fault conditions of the carbon canister solenoid valve. Summary of the invention

[0004] In view of the above technical problems, the present disclosure provides a method and system for diagnosing a carbon canister solenoid valve. The carbon canister solenoid valve diagnosis system of the present disclosure can measure the air pressure in the pipeline and compare the measured air pressure with the corresponding valve threshold to diagnose the carbon canister solenoid valve.

[0005] In a first aspect, the present disclosure provides a system for diagnosing a carbon canister solenoid valve (100), wherein the carbon canister solenoid valve (100) can be connected to a carbon canister (200) via a pipeline. The system may include: an air pressure sensor (300), wherein the air pressure sensor (300) is coupled between the carbon canister (200) and the carbon canister solenoid valve (100) and is configured to measure the air pressure in the pipeline between the carbon canister (200) and the carbon canister solenoid valve (100); and an engine control unit (400), wherein the engine control unit (400) is electrically connected to the carbon canister solenoid valve (100) and the air pressure sensor (300) respectively and is configured to: transmit an instruction to the carbon canister solenoid valve (100) to instruct the carbon canister solenoid valve (100) to open or close, receive the measured air pressure from the air pressure sensor (300), and compare the measured air pressure with a corresponding valve opening threshold or valve closing threshold to diagnose the carbon canister solenoid valve (100).

[0006] According to one embodiment of the present application, optionally, when the engine control unit (400) instructs the carbon canister solenoid valve (100) to open, the engine control unit (400) can be configured to receive the measured air pressure from the air pressure sensor (300) and compare the most recently received measured air pressure with the valve opening threshold to diagnose the carbon canister solenoid valve (100).

[0007] According to one embodiment of the present application, optionally, when the most recently received measured air pressure - the previously received measured air pressure ≤ the first valve opening threshold, the engine control unit (400) can be configured to determine that the carbon canister solenoid valve (100) is fully opened; when the first valve opening threshold < the most recently received measured air pressure - the previously received measured air pressure ≤ the second valve opening threshold, the engine control unit (400) can be configured to determine that the carbon canister solenoid valve (100) is effectively opened; when the second valve opening threshold < the most recently received measured air pressure - the previously received measured air pressure ≤ the third valve opening threshold, the engine control unit (400) can be configured to determine that the carbon canister solenoid valve (100) is opened; when the air pressure difference > the third valve opening threshold, the engine control unit (400) can be configured to determine that the carbon canister solenoid valve (100) is not opened.

[0008] According to one embodiment of the present application, optionally, the first valve opening threshold may be -70 hPa, the second valve opening threshold may be -30 hPa, and the third valve opening threshold may be -10 hPa.

[0009] According to one embodiment of the present application, the engine control unit (400) may be optionally configured to issue a warning signal indicating that the carbon canister solenoid valve (100) is not opened in response to determining that the carbon canister solenoid valve (100) is not opened.

[0010] According to one embodiment of the present application, optionally, when the engine control unit (400) instructs the carbon canister solenoid valve (100) to close, the engine control unit (400) can be configured to receive the measured air pressure from the air pressure sensor (300) and compare the measured air pressure with the valve closing threshold to diagnose the carbon canister solenoid valve (100).

[0011] According to one embodiment of the present application, optionally, when the measured air pressure - reference air pressure ≥ the first valve closing threshold, the engine control unit (400) can be configured to determine that the carbon canister solenoid valve (100) is fully closed; when the first valve closing threshold > the measured air pressure - reference air pressure ≥ the second valve closing threshold, the engine control unit (400) can be configured to determine that the carbon canister solenoid valve (100) is closed; when the measured air pressure - reference air pressure < - the second valve closing threshold, the engine control unit (400) can be configured to determine that the carbon canister solenoid valve (100) is not closed.

[0012] According to one embodiment of the present application, optionally, the first valve closing threshold may be -5 hPa, and the second valve closing threshold may be -10 hPa.

[0013] According to one embodiment of the present application, optionally, the engine control unit (400) may be configured to issue a warning signal indicating that the carbon canister solenoid valve (100) is not closed in response to determining that the carbon canister solenoid valve (100) is not closed.

[0014] According to one embodiment of the present application, optionally, the air pressure sensor (300) may be configured to: periodically transmit the measured air pressure to the engine control unit (400); or transmit the measured air pressure to the engine control unit (400) in response to a trigger signal from the engine control unit (400).

[0015] According to one embodiment of the present application, optionally, the system may further include: an intake pipe, wherein the intake pipe may be connected to the carbon canister solenoid valve (100) and to the engine via a pipeline.

[0016] In a second aspect, the present disclosure provides a method for diagnosing a carbon canister solenoid valve (100) of a vehicle, wherein the carbon canister solenoid valve (100) can be connected to a carbon canister (200) via a pipeline. The method may include: an engine control unit (400) can transmit an instruction to open or close the carbon canister solenoid valve (100) to the carbon canister solenoid valve (100) and an air pressure sensor (300), wherein the air pressure sensor (300) is coupled between the carbon canister (200) and the carbon canister solenoid valve (100); and the air pressure sensor (300) can measure the air pressure in the pipeline between the carbon canister (200) and the carbon canister solenoid valve (100) in response to receiving the opening or closing instruction, and compare the measured air pressure with a valve opening threshold or a valve closing threshold corresponding to the opening or closing instruction to diagnose the carbon canister solenoid valve (100).

[0017] According to one embodiment of the present application, optionally, when the engine control unit (400) instructs the carbon canister solenoid valve (100) to open, the engine control unit (400) may receive the measured air pressure from the air pressure sensor (300), and compare the most recently received measured air pressure with the valve opening threshold to diagnose the carbon canister solenoid valve (100), wherein the diagnosis includes: when the most recently received measured air pressure - the previously received measured air pressure ≤ the first valve opening threshold, the engine control unit (400) may be configured to determine that the carbon canister solenoid valve (100) is fully opened; when When the first valve opening threshold value is less than the most recently received measured air pressure – the previously received measured air pressure ≤ the second valve opening threshold value, the engine control unit (400) can be configured to determine that the carbon canister solenoid valve (100) is effectively opened; when the second valve opening threshold value is less than the most recently received measured air pressure – the previously received measured air pressure ≤ the third valve opening threshold value, the engine control unit (400) can be configured to determine that the carbon canister solenoid valve (100) is opened; when the air pressure difference is greater than the third valve opening threshold value, the engine control unit (400) can be configured to determine that the carbon canister solenoid valve (100) is not opened.

[0018] According to one embodiment of the present application, optionally, when the engine control unit (400) instructs the carbon canister solenoid valve (100) to close, the engine control unit (400) may receive the measured air pressure from the air pressure sensor (300), and compare the measured air pressure with the valve closing threshold to diagnose the carbon canister solenoid valve (100), wherein the diagnosis includes: when the measured air pressure - reference air pressure ≥ the first valve closing threshold, the engine control unit (400) may be configured to determine that the carbon canister solenoid valve (100) is fully closed; when the first valve closing threshold > the measured air pressure - reference air pressure ≥ the second valve closing threshold, the engine control unit (400) may be configured to determine that the carbon canister solenoid valve (100) is closed; when the measured air pressure - reference air pressure < - the second valve closing threshold, the engine control unit (400) may be configured to determine that the carbon canister solenoid valve (100) is not closed.

[0019] In a third aspect, the present disclosure provides a vehicle comprising the system for diagnosing a canister solenoid valve (100) as described above.

[0020] The carbon canister solenoid valve diagnostic system disclosed in the present invention can not only diagnose whether the carbon canister solenoid valve is in the correct closed or open state instructed by the engine control unit, but also can determine the severity of the carbon canister solenoid valve failure when it is determined that the carbon canister solenoid valve is faulty. For example, when the engine control unit instructs the carbon canister solenoid valve to open, the engine control unit can further determine whether the carbon canister solenoid valve is in an effective open state, an open state, or an unopened state when it is determined that the carbon canister solenoid valve is not fully open, and give corresponding different warnings. For example, when the engine control unit instructs the carbon canister solenoid valve to close, the engine control unit can further determine whether the carbon canister solenoid valve is in a closed state or an unclosed state when it is determined that the carbon canister solenoid valve is not fully closed, and give corresponding different warnings.

[0021] These and other features and advantages will become apparent by reading the following detailed description and by reference to the associated drawings.It is to be understood that the foregoing general description and the following detailed description are illustrative only and are not restrictive of the aspects of what is claimed. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to understand in detail the manner in which the above features of the present disclosure are used, the above briefly summarized contents may be described in more detail with reference to various embodiments, some of which are shown in the accompanying drawings. However, it should be noted that the accompanying drawings only show certain typical aspects of the present disclosure and should not be considered to limit its scope, as the description may allow for other equally effective aspects.

[0023] Figure 1 A structural schematic diagram of a canister solenoid valve diagnostic system according to an embodiment of the present disclosure is illustrated.

[0024] Figure 2 A flow chart illustrating a canister solenoid valve diagnostic method according to an embodiment of the present disclosure is illustrated.

[0025] Figure 3 A schematic structural diagram of a vehicle including a canister solenoid valve diagnostic system according to an embodiment of the present disclosure is illustrated. DETAILED DESCRIPTION

[0026] In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the described embodiments. However, it will be apparent to those skilled in the art that the described embodiments may be practiced without some or all of these specific details. In other embodiments, well-known structures or processing steps are not described in detail to avoid unnecessarily obscuring the concepts of the present disclosure.

[0027] In the description of the embodiments of the present disclosure, it should be noted that, unless otherwise specified, the term "plurality" means more than two; the term "and / or" is merely a description of the association relationship of associated objects, indicating that three relationships may exist, for example, A and / or B may represent: A exists alone, A and B exist at the same time, and B exists alone; the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship. In addition, the terms "first", "second", "third", etc. are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which the present disclosure belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure; the terms "including" and "having" in the specification and claims of the present disclosure and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0029] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present disclosure. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0030] In the following description, numerous specific details (such as examples of specific components, circuits, and processes) are set forth to provide a thorough understanding of the present disclosure. As used herein, the terms "coupled", "coupled", "connected" or "connected" mean directly connected to or connected through one or more intermediate media or components. For example, "coupled via a pipeline", "coupled via a pipeline", "connected via a pipeline" or "connected via a pipeline" as used herein means connected to or connected through a pipeline using a pipeline. For example, "electrically coupled", "electrically coupled", "electrically connected" or "electrically connected" as used herein means electrically connected or electrically conductive, and can thus be used to transmit electrical signals. For those of ordinary skill in the art, the specific meanings of the above terms in the present disclosure can be understood depending on the specific circumstances. Moreover, in the following description and for the purpose of explanation, specific naming is set forth to provide a thorough understanding of the various embodiments of the present disclosure. However, it will be apparent to those skilled in the art that each example embodiment can be practiced without these specific details. In other examples, well-known circuits and devices are shown in block diagram form to avoid confusing the present disclosure.

[0031] For simplicity, the present disclosure is described in conjunction with a “vehicle” in the specification, but the “vehicle” of the embodiments described herein is not limited to motor vehicles but is applicable to other types of transportation vehicles equipped with a fuel evaporation control system.

[0032] The vehicle's carbon canister and carbon canister solenoid valve are part of the vehicle's fuel evaporation control system. The existing evaporation control system only has a carbon canister solenoid valve circuit diagnostic function. This circuit diagnostic function can only check whether the carbon canister solenoid valve circuit is working properly. However, in actual use, the carbon canister solenoid valve may not be fully closed or opened due to some reasons (such as valve stuck, etc.). And in this case, the circuit of the carbon canister solenoid valve works normally without abnormalities. For example, the carbon canister solenoid valve circuit is not disconnected, but there is contamination inside the carbon canister solenoid valve and the valve of the carbon canister solenoid valve cannot work properly. The above-mentioned circuit diagnostic function cannot identify such fault conditions. This may lead to an erroneous judgment that there is a leakage problem in the intake system. Therefore, it is urgently desired to provide a method for diagnosing various fault conditions of the carbon canister solenoid valve.

[0033] In order to solve one or more of the above problems, the present disclosure provides a method and system for diagnosing a carbon canister solenoid valve. The carbon canister solenoid valve diagnosis method and system will be specifically described below in conjunction with the accompanying drawings and some embodiments will be listed to illustrate some application scenarios.

[0034] The following is a system for diagnosing a carbon canister solenoid valve, taking a fuel vehicle provided with a fuel evaporation control system as an example. Generally speaking, a fuel vehicle may include a fuel evaporation control system. The fuel evaporation control system may include a carbon canister solenoid valve (100) and a carbon canister (200). The carbon canister solenoid valve (100) may be connected to the carbon canister (200) via a pipeline, wherein the carbon canister solenoid valve (100) may be connected to an intake pipe via a pipeline, and the intake pipe may be connected to an engine of the vehicle.

[0035] Figure 1 The structure diagram of the system 10 for diagnosing the carbon canister solenoid valve according to an embodiment of the present disclosure is illustrated. Figure 1As shown in , the system 10 for diagnosing a carbon canister solenoid valve may include an air pressure sensor (300) and an engine control unit (400). The air pressure sensor (300) may be coupled between the carbon canister (200) and the carbon canister solenoid valve (100), and may be configured to measure the air pressure in the pipeline between the carbon canister (200) and the carbon canister solenoid valve (100). The engine control unit (400) may be electrically connected to the carbon canister solenoid valve (100) and the air pressure sensor (300), respectively, and may be configured to transmit an instruction to the carbon canister solenoid valve (100) to open or close the carbon canister solenoid valve (100), receive the measured air pressure from the air pressure sensor (300), and compare the measured air pressure with the corresponding valve opening threshold or valve closing threshold to diagnose the carbon canister solenoid valve (100).

[0036] The air pressure sensor (300) may be a device for measuring the pressure of a gas, and any type of air pressure sensor may be applicable to the present disclosure. The present disclosure does not limit this. The engine control unit (400) may be an original engine control unit of the vehicle, and is loaded with a carbon canister solenoid valve diagnostic function.

[0037] When the engine control unit (400) instructs the carbon canister solenoid valve (100) to open, the air pressure in the pipeline between the carbon canister (200) and the carbon canister solenoid valve (100) may drop to a negative value. If the carbon canister solenoid valve (100) cannot be switched to an open state, the air pressure sensor (300) may not detect a pressure change, which means that the carbon canister solenoid valve may be faulty (such as unable to open, for example, unable to open completely).

[0038] In an optional embodiment, when the engine control unit (400) instructs the carbon canister solenoid valve (100) to open, the engine control unit (400) may be configured to receive the measured air pressure from the air pressure sensor (300), and compare the most recently received measured air pressure with the valve opening threshold to diagnose the carbon canister solenoid valve (100). As an example, when the most recently received measured air pressure - the previously received measured air pressure ≤ the first valve opening threshold, the engine control unit (400) may be configured to determine that the carbon canister solenoid valve (100) is fully opened. In some cases, fully open means that the valve opening of the carbon canister solenoid valve (100) reaches 95% to 100%. As another example, when the first valve opening threshold < the most recently received measured air pressure - the previously received measured air pressure ≤ the second valve opening threshold, the engine control unit (400) may be configured to determine that the carbon canister solenoid valve (100) is effectively opened. In some cases, effective opening refers to the valve opening of the carbon canister solenoid valve (100) reaching 80% to 95%. As another example, when the second valve opening threshold < the most recently received measured air pressure - the previously received measured air pressure ≤ the third valve opening threshold, the engine control unit (400) may be configured to determine that the carbon canister solenoid valve (100) is open. In some cases, effective opening refers to the valve opening of the carbon canister solenoid valve (100) reaching 30% to 80%. As another example, when the air pressure difference > the third valve opening threshold, the engine control unit (400) may be configured to determine that the carbon canister solenoid valve (100) is not open. In some cases, effective opening refers to the valve opening of the carbon canister solenoid valve (100) reaching 0% to 30%. In one example, the first valve opening threshold may be between -80hPa and -60hPa, the second valve opening threshold may be between -40hPa and -30hPa, and the third valve opening threshold may be between -20hPa and -5hPa. In an optional example, the first valve opening threshold may be -70 hPa, the second valve opening threshold may be -30 hPa, and the third valve opening threshold may be -10 hPa. In some cases, these thresholds may be calibrated during a functional calibration phase and stored in an electronic control unit (ECU) system.

[0039] In an optional embodiment, the engine control unit (400) may be configured to issue a warning signal indicating that the carbon canister solenoid valve (100) is not open in response to determining that the carbon canister solenoid valve (100) is not open. For example, the engine control unit (400) may issue a warning signal indicating that the carbon canister solenoid valve (100) is not open to the vehicle interaction system, and the vehicle interaction system may notify the driver to check the carbon canister solenoid valve.

[0040] When the engine control unit (400) instructs the carbon canister solenoid valve (100) to close, the air pressure in the pipeline between the carbon canister (200) and the carbon canister solenoid valve (100) can be kept close to the ambient air pressure. If the carbon canister solenoid valve (100) cannot be closed due to some reasons (such as being contaminated by dust), the air pressure sensor (300) may display a negative pressure value, which means that the carbon canister solenoid valve may have a fault (such as being unable to close, for example, unable to close completely).

[0041] In an optional embodiment, when the engine control unit (400) instructs the carbon canister solenoid valve (100) to close, the engine control unit (400) may be configured to receive the measured air pressure from the air pressure sensor (300) and compare the measured air pressure with the valve closing threshold to diagnose the carbon canister solenoid valve (100). As an example, when the measured air pressure - reference air pressure ≥ the first valve closing threshold, the engine control unit (400) may be configured to determine that the carbon canister solenoid valve (100) is fully closed. In some cases, fully closed means that the valve closing degree of the carbon canister solenoid valve (100) reaches 85% to 100%. As another example, when the first valve closing threshold > the measured air pressure - reference air pressure ≥ the second valve closing threshold, the engine control unit (400) may be configured to determine that the carbon canister solenoid valve (100) is closed. In some cases, closed means that the valve closing degree of the carbon canister solenoid valve (100) reaches 40% to 85%. As another example, when the measured air pressure - reference air pressure <- second valve closing threshold, the engine control unit (400) may be configured to determine that the carbon canister solenoid valve (100) is not closed. In some cases, not closed means that the valve closing degree of the carbon canister solenoid valve (100) reaches 0% to 40%. In one example, the first valve closing threshold may be between -2hPa and -8hPa, and the second valve closing threshold may be between -8hPa and -15hPa. In an optional embodiment, the first valve closing threshold may be -5hPa, and the second valve closing threshold may be -10hPa. In some cases, these thresholds may be calibrated during the functional calibration phase and stored in the electronic control unit (ECU) system.

[0042] In an optional embodiment, the engine control unit (400) may be configured to issue a warning signal that the carbon canister solenoid valve (100) is not closed in response to determining that the carbon canister solenoid valve (100) is not closed. For example, the engine control unit (400) may issue a warning signal that the carbon canister solenoid valve (100) is not closed to the vehicle interaction system, and the vehicle interaction system may notify the driver to check the carbon canister solenoid valve.

[0043] In an optional embodiment, the air pressure sensor (300) may be configured to transmit the measured air pressure to the engine control unit (400) periodically (e.g., once every second, once every minute, or once every 30 minutes). In an alternative embodiment, the air pressure sensor (300) may be configured to transmit the measured air pressure to the engine control unit (400) in response to a trigger signal from the engine control unit (400) (e.g., an opening instruction or a closing instruction from the engine control unit (400)). In yet another alternative embodiment, the air pressure sensor (300) may be configured to transmit the measured air pressure to the engine control unit (400) in response to detecting a change in the air pressure.

[0044] Figure 2 A flow chart illustrating a method 20 for diagnosing a carbon canister solenoid valve according to an embodiment of the present disclosure. In one embodiment, the method 20 may include, at box 205, an engine control unit (400) may transmit a command to open or close the carbon canister solenoid valve (100) to the carbon canister solenoid valve (100) and an air pressure sensor (300), wherein the air pressure sensor (300) is coupled between the carbon canister (200) and the carbon canister solenoid valve (100). The method 20 may include, at box 210, the air pressure sensor (300) may measure the air pressure in the pipeline between the carbon canister (200) and the carbon canister solenoid valve (100) in response to receiving the command to open or close, and compare the measured air pressure with a valve opening threshold or a valve closing threshold corresponding to the command to open or close to diagnose the carbon canister solenoid valve (100).

[0045] In an optional embodiment, when the engine control unit (400) instructs the carbon canister solenoid valve (100) to open, the engine control unit (400) may receive the measured air pressure from the air pressure sensor (300), and compare the most recently received measured air pressure with the valve opening threshold to diagnose the carbon canister solenoid valve (100), wherein the diagnosis includes: when the most recently received measured air pressure - the previously received measured air pressure ≤ the first valve opening threshold, the engine control unit (400) may be configured to determine that the carbon canister solenoid valve (100) is fully opened; when the first valve opening threshold When the opening threshold value is less than the most recently received measured air pressure - the previously received measured air pressure ≤ the second valve opening threshold value, the engine control unit (400) may be configured to determine that the carbon canister solenoid valve (100) is effectively opened; when the second valve opening threshold value is less than the most recently received measured air pressure - the previously received measured air pressure ≤ the third valve opening threshold value, the engine control unit (400) may be configured to determine that the carbon canister solenoid valve (100) is opened; when the air pressure difference is greater than the third valve opening threshold value, the engine control unit (400) may be configured to determine that the carbon canister solenoid valve (100) is not opened. In one example, the first valve opening threshold value may be between -80hPa and -60hPa, the second valve opening threshold value may be between -40hPa and -30hPa, and the third valve opening threshold value may be between -20hPa and -5hPa. In an optional example, the first valve opening threshold value may be -70hPa, the second valve opening threshold value may be -30hPa, and the third valve opening threshold value may be -10hPa. In some cases, these thresholds may be calibrated during a functional calibration phase and stored in an electronic control unit (ECU) system.

[0046] In an optional embodiment, when the engine control unit (400) instructs the carbon canister solenoid valve (100) to close, the engine control unit (400) may receive the measured air pressure from the air pressure sensor (300) and compare the measured air pressure with the valve closing threshold to diagnose the carbon canister solenoid valve (100), wherein the diagnosis includes: when the measured air pressure - reference air pressure ≥ the first valve closing threshold, the engine control unit (400) may be configured to determine that the carbon canister solenoid valve (100) is fully closed; when the first valve closing threshold > the measured air pressure - reference air pressure ≥ the second valve closing threshold, the engine control unit (400) may be configured to determine that the carbon canister solenoid valve (100) is closed; when the measured air pressure - reference air pressure < - the second valve closing threshold, the engine control unit (400) may be configured to determine that the carbon canister solenoid valve (100) is not closed. In one example, the first valve opening threshold may be between -80 hPa and -60 hPa, the second valve opening threshold may be between -40 hPa and -30 hPa, and the third valve opening threshold may be between -20 hPa and -5 hPa. In an optional example, the first valve opening threshold may be -70 hPa, the second valve opening threshold may be -30 hPa, and the third valve opening threshold may be -10 hPa. In some cases, these thresholds may be calibrated and stored in an electronic control unit (ECU) system during a functional calibration phase.

[0047] Figure 3 A schematic diagram of the structure of a vehicle 300 including a canister solenoid valve diagnostic system according to an embodiment of the present disclosure is illustrated. Figure 3 As shown in FIG. , the vehicle 300 includes the above-referenced Figure 1 A system 10 for diagnosing a canister solenoid valve (100) is described.

[0048] The carbon canister solenoid valve diagnostic system disclosed in the present invention can not only diagnose whether the carbon canister solenoid valve is in the correct closed or open state instructed by the engine control unit, but also can determine the severity of the carbon canister solenoid valve failure when it is determined that the carbon canister solenoid valve is faulty. For example, when the engine control unit instructs the carbon canister solenoid valve to open, the engine control unit can further determine whether the carbon canister solenoid valve is in an effective open state, an open state, or an unopened state when it is determined that the carbon canister solenoid valve is not fully open, and give corresponding different warnings. For example, when the engine control unit instructs the carbon canister solenoid valve to close, the engine control unit can further determine whether the carbon canister solenoid valve is in a closed state or an unclosed state when it is determined that the carbon canister solenoid valve is not fully closed, and give corresponding different warnings.

[0049] In an optional embodiment, the carbon canister solenoid valve diagnostic system of the present disclosure can be used in conjunction with the carbon canister solenoid valve circuit diagnostic function to check whether the carbon canister solenoid valve circuit is operating normally. For example, when the carbon canister solenoid valve diagnostic system determines that the carbon canister solenoid valve is not fully closed or fully open, the carbon canister solenoid valve circuit diagnostic function can be used to determine whether the carbon canister solenoid valve circuit is operating normally. If it is detected that the carbon canister solenoid valve circuit is not operating normally, an emergency alarm (e.g., a red alarm) may be issued. If it is detected that the carbon canister solenoid valve circuit is operating normally, the opening of the carbon canister solenoid valve is further detected when the engine control unit instructs the carbon canister solenoid valve to open. If the opening of the carbon canister solenoid valve is maintained below 30%, an emergency alarm (e.g., a red alarm) may be issued. If the opening of the carbon canister solenoid valve is maintained below 30%, a general alarm (e.g., a yellow alarm) may be issued.

[0050] The "range" disclosed herein is defined in the form of a lower limit and an upper limit, and a given range is defined by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundaries of the particular range. The range defined in this way can be inclusive or exclusive of the end values, and can be arbitrarily combined, that is, any lower limit can be combined with any upper limit to form a range. In this application, unless otherwise specified, the numerical range "ab" represents an abbreviation of any real number combination between a and b, where a and b are both real numbers.

[0051] In this application, unless otherwise specified, all embodiments and preferred embodiments mentioned herein can be combined with each other to form a new technical solution.

[0052] In the present application, unless otherwise specified, all technical features and preferred features mentioned herein can be combined with each other to form new technical solutions. Although the present application has been described with reference to optional embodiments, various improvements can be made thereto and components thereof can be replaced with equivalents without departing from the scope of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any manner. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A system for diagnosing a carbon canister solenoid valve (100), wherein the carbon canister solenoid valve (100) is connected to a carbon canister (200) via a pipeline, the system comprising: An air pressure sensor (300), wherein the air pressure sensor (300) is coupled between the carbon canister (200) and the carbon canister solenoid valve (100) and is configured to measure the air pressure in a pipeline between the carbon canister (200) and the carbon canister solenoid valve (100); as well as An engine control unit (400), wherein the engine control unit (400) is electrically connected to the carbon canister solenoid valve (100) and the air pressure sensor (300) respectively and is configured to: transmit an instruction to the carbon canister solenoid valve (100) to instruct the carbon canister solenoid valve (100) to open or close, receive a measured air pressure from the air pressure sensor (300), and compare the measured air pressure with a corresponding valve opening threshold or valve closing threshold to diagnose the carbon canister solenoid valve (100).

2. The system according to claim 1, characterized in that When the engine control unit (400) instructs the carbon canister solenoid valve (100) to open, the engine control unit (400) is configured to receive the measured air pressure from the air pressure sensor (300) and compare the most recently received measured air pressure with the valve opening threshold to diagnose the carbon canister solenoid valve (100).

3. The system according to claim 2, characterized in that: When the most recently received measured air pressure minus the previously received measured air pressure ≤ the first valve opening threshold, the engine control unit (400) is configured to determine that the carbon canister solenoid valve (100) is fully opened; When the first valve opening threshold value < the most recently received measured air pressure - the previously received measured air pressure ≤ the second valve opening threshold value, the engine control unit (400) is configured to determine that the carbon canister solenoid valve (100) is effectively opened; When the second valve opening threshold value < the most recently received measured air pressure - the previously received measured air pressure ≤ the third valve opening threshold value, the engine control unit (400) is configured to determine that the carbon canister solenoid valve (100) is opened; When the air pressure difference is greater than a third valve opening threshold, the engine control unit (400) is configured to determine that the carbon canister solenoid valve (100) is not opened.

4. The system according to claim 3, characterized in that The first valve opening threshold is -70 hPa, the second valve opening threshold is -30 hPa, and the third valve opening threshold is -10 hPa.

5. The system according to claim 3, characterized in that The engine control unit (400) is configured to issue a warning signal indicating that the canister solenoid valve (100) is not opened in response to determining that the canister solenoid valve (100) is not opened.

6. The system according to claim 1, wherein: When the engine control unit (400) instructs the carbon canister solenoid valve (100) to close, the engine control unit (400) is configured to receive the measured air pressure from the air pressure sensor (300) and compare the measured air pressure with the valve closing threshold to diagnose the carbon canister solenoid valve (100).

7. The system according to claim 6, characterized in that: When the measured air pressure minus the reference air pressure ≥ the first valve closing threshold, the engine control unit (400) is configured to determine that the carbon canister solenoid valve (100) is fully closed; When the first valve closing threshold value>the measured air pressure-reference air pressure≥the second valve closing threshold value, the engine control unit (400) is configured to determine that the carbon canister solenoid valve (100) is closed; When the measured air pressure−reference air pressure<−a second valve closing threshold, the engine control unit (400) is configured to determine that the canister solenoid valve (100) is not closed.

8. The system according to claim 7, characterized in that The first valve closing threshold is -5 hPa and the second valve closing threshold is -10 hPa.

9. The system according to claim 7, characterized in that In response to determining that the carbon canister solenoid valve (100) is not closed, the engine control unit issues a warning signal that the carbon canister solenoid valve (100) is not closed.

10. The system according to claim 1, wherein: The air pressure sensor (300) is configured to: periodically transmitting the measured air pressure to the engine control unit (400); or The measured air pressure is transmitted to the engine control unit (400) in response to a trigger signal from the engine control unit (400).

11. The system according to claim 1, characterized in that Further including: An intake pipe is connected to the canister solenoid valve (100) and to the engine via a pipe.

12. A method for diagnosing a carbon canister solenoid valve (100) of a vehicle, wherein the carbon canister solenoid valve (100) is connected to a carbon canister (200) via a pipeline, comprising: The engine control unit (400) transmits a command to open or close the carbon canister solenoid valve (100) and the air pressure sensor (300), wherein the air pressure sensor (300) is coupled between the carbon canister (200) and the carbon canister solenoid valve (100); and The air pressure sensor (300) measures the air pressure in the pipeline between the carbon canister (200) and the carbon canister solenoid valve (100) in response to receiving the opening or closing instruction, and compares the measured air pressure with the valve opening threshold or valve closing threshold corresponding to the opening or closing instruction to diagnose the carbon canister solenoid valve (100).

13. The method according to claim 12, characterized in that When the engine control unit (400) instructs the carbon canister solenoid valve (100) to open, the engine control unit (400) receives the measured air pressure from the air pressure sensor (300), and compares the most recently received measured air pressure with the valve opening threshold to diagnose the carbon canister solenoid valve (100), wherein the diagnosis includes: When the most recently received measured air pressure minus the previously received measured air pressure ≤ the first valve opening threshold, the engine control unit (400) is configured to determine that the carbon canister solenoid valve (100) is fully opened; When the first valve opening threshold value < the most recently received measured air pressure - the previously received measured air pressure ≤ the second valve opening threshold value, the engine control unit (400) is configured to determine that the carbon canister solenoid valve (100) is effectively opened; When the second valve opening threshold value < the most recently received measured air pressure - the previously received measured air pressure ≤ the third valve opening threshold value, the engine control unit (400) is configured to determine that the carbon canister solenoid valve (100) is opened; When the air pressure difference is greater than a third valve opening threshold, the engine control unit (400) is configured to determine that the carbon canister solenoid valve (100) is not opened.

14. The method according to claim 12, characterized in that When the engine control unit (400) instructs the carbon canister solenoid valve (100) to close, the engine control unit (400) receives the measured air pressure from the air pressure sensor (300), and compares the measured air pressure with the valve closing threshold to diagnose the carbon canister solenoid valve (100), wherein the diagnosis includes: When the measured air pressure minus the reference air pressure ≥ the first valve closing threshold, the engine control unit (400) is configured to determine that the carbon canister solenoid valve (100) is fully closed; When the first valve closing threshold value>the measured air pressure-reference air pressure≥the second valve closing threshold value, the engine control unit (400) is configured to determine that the carbon canister solenoid valve (100) is closed; When the measured air pressure−reference air pressure<−a second valve closing threshold, the engine control unit (400) is configured to determine that the canister solenoid valve (100) is not closed.

15. A vehicle comprising a system as claimed in any one of claims 1 to 11.

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