Control method, device and equipment of fuel system and storage medium

Abstract

The present disclosure provides a control method, device and equipment of a fuel system and a storage medium, and belongs to the field of sensors. The method comprises: when a pump current flag bit is valid, determining a first air-fuel ratio value according to a pump current value of a wide-range oxygen sensor; and controlling the air-fuel ratio of the fuel system according to the first air-fuel ratio value and a set air-fuel ratio range. That is, when the pump current flag bit is valid, the air-fuel ratio of the fuel system is further controlled according to the first air-fuel ratio value and the set air-fuel ratio range. Since the relationship between the first air-fuel ratio value and the set air-fuel ratio range can reflect whether the running state of the fuel system is normal, the air-fuel ratio of the fuel system can be more accurately controlled, so that the pollutants in the automobile exhaust can be effectively controlled.

Description

Technical Field

[0001] This disclosure relates to the field of sensors, and in particular to a control method, apparatus, device, and storage medium for a fuel system. Background Technology

[0002] Currently, fuel control systems are used to reduce pollution in vehicle exhaust. A commonly used fuel control system is a closed-loop air-fuel ratio control system based on a wide-range oxygen sensor. This system maintains the air-fuel ratio near its ideal value, thereby reducing the pollutant content in exhaust gases. The air-fuel ratio (excess air coefficient) is a crucial factor affecting the pollutant content in vehicle exhaust. It indicates the richness or leanness of the fuel-air mixture in the cylinder, where the mixture refers to the mixture of fuel and air. When the air-fuel ratio is greater than the ideal value of 1, the mixture is lean, containing too little fuel, resulting in a large amount of unburned hydrocarbons in the exhaust. When the air-fuel ratio is less than the ideal value of 1, the mixture is rich, containing too much fuel, leading to incomplete combustion and an increase in carbon monoxide and hydrocarbon content in the exhaust.

[0003] In related technologies, the control method for the fuel system includes: acquiring the pump current flag of a wide-range oxygen sensor; when the pump current flag is valid, using closed-loop control of the air-fuel ratio of the fuel system to maintain the air-fuel ratio near the ideal value.

[0004] However, in practical applications, there have been many instances where the air-fuel ratio is not near the ideal value when the pump current flag of the wide-range oxygen sensor is effective. In such cases, if closed-loop control is used for the air-fuel ratio of the fuel system, it will lead to a large deviation in the fuel control system and serious exceedance of vehicle exhaust emissions. Summary of the Invention

[0005] This disclosure provides a fuel system control method, apparatus, device, and storage medium, which can effectively prevent excessive vehicle exhaust emissions caused by deviations in the fuel control system. The technical solution includes at least the following:

[0006] In a first aspect, a method for controlling a fuel system is provided, comprising: acquiring a pump current flag bit of a wide-range oxygen sensor; when the pump current flag bit is valid, determining a first air-fuel ratio value based on the pump current value of the wide-range oxygen sensor; and controlling the air-fuel ratio of the fuel system based on the first air-fuel ratio value and a set air-fuel ratio range.

[0007] Optionally, controlling the air-fuel ratio of the fuel system based on the first air-fuel ratio value and a set air-fuel ratio range includes: in response to determining that the first air-fuel ratio value is outside the air-fuel ratio range for a first set time, controlling the fuel system with a set second air-fuel ratio value as the target air-fuel ratio.

[0008] Optionally, controlling the air-fuel ratio of the fuel system based on the first air-fuel ratio value and the set air-fuel ratio range includes: in response to determining that the first air-fuel ratio value is within the air-fuel ratio range, or in response to determining that the duration of the first air-fuel ratio value being outside the air-fuel ratio range is less than a first set duration, controlling the air-fuel ratio of the fuel system in a closed-loop control manner, so that the air-fuel ratio of the fuel system reaches a set third air-fuel ratio value.

[0009] Optionally, the method further includes: after controlling the fuel system with a set second air-fuel ratio as the target air-fuel ratio, in response to determining that the first air-fuel ratio value has been within the air-fuel ratio range for a second set time, controlling the air-fuel ratio of the fuel system using the closed-loop control method, so that the air-fuel ratio of the fuel system reaches a set third air-fuel ratio value.

[0010] Optionally, the method further includes: in response to determining that the first air-fuel ratio value is outside the air-fuel ratio range for a duration of the first set duration, controlling the wide-range oxygen sensor to stop heating.

[0011] Optionally, the method further includes: when the pump current flag is invalid, controlling the fuel system with a set second air-fuel ratio value as the target air-fuel ratio.

[0012] Secondly, a control device for a fuel system is also provided, comprising: an acquisition module for acquiring a pump current flag bit of a wide-range oxygen sensor; a determination module for determining a first air-fuel ratio value based on the pump current value of the wide-range oxygen sensor when the pump current flag bit is valid; and a first control module for controlling the air-fuel ratio of the fuel system based on the first air-fuel ratio value and a set air-fuel ratio range.

[0013] Optionally, the first control module is further configured to control the fuel system with a set second air-fuel ratio as the target air-fuel ratio in response to determining that the first air-fuel ratio value is outside the air-fuel ratio range for a first set time.

[0014] Optionally, the first control module is further configured to, in response to determining that the first air-fuel ratio value is within the air-fuel ratio range, or in response to determining that the duration of the first air-fuel ratio value being outside the air-fuel ratio range is less than a first set duration, control the air-fuel ratio of the fuel system in a closed-loop control manner, so that the air-fuel ratio of the fuel system reaches a set third air-fuel ratio value.

[0015] Optionally, the first control module is further configured to, after controlling the fuel system with the set second air-fuel ratio as the target air-fuel ratio, in response to determining that the first air-fuel ratio value has been within the air-fuel ratio range for a second set time, control the air-fuel ratio of the fuel system in a closed-loop control manner so that the air-fuel ratio of the fuel system reaches a set third air-fuel ratio value.

[0016] Optionally, the device further includes a heating control module, configured to control the wide-range oxygen sensor to stop heating in response to determining that the first air-fuel ratio value is outside the air-fuel ratio range for a first set time.

[0017] Optionally, the device further includes a second control module, used to control the fuel system with a set second air-fuel ratio as the target air-fuel ratio when the pump current flag is invalid.

[0018] Thirdly, a computer device is also provided, comprising: a memory and a processor, wherein the memory stores at least one computer program, the at least one computer program being loaded and executed by the processor to perform the fuel system control method described in the above embodiments.

[0019] Fourthly, a computer-readable storage medium is also provided, wherein at least one computer program is stored in the computer-readable storage medium, the at least one computer program being loaded and executed by a processor to perform the fuel system control method described in the above embodiments.

[0020] Fifthly, a computer program product is provided, including a computer program / instructions that, when executed by a processor, implement the method described in the first aspect.

[0021] The beneficial effects of this embodiment are as follows: In this embodiment, when the pump current flag is valid, a first air-fuel ratio value is determined based on the pump current value of the wide-range oxygen sensor; the air-fuel ratio of the fuel system is controlled based on the first air-fuel ratio value and a set air-fuel ratio range. That is, when the pump current flag is valid, the air-fuel ratio of the fuel system is further controlled based on the first air-fuel ratio value and the set air-fuel ratio range. Since the relationship between the first air-fuel ratio value and the set air-fuel ratio range can reflect whether the operating state of the fuel system is normal, the air-fuel ratio of the fuel system can be controlled more accurately, thus effectively controlling pollutants in vehicle exhaust. Attached Figure Description

[0022] Figure 1 A flowchart illustrating a control method for a fuel system provided in an exemplary embodiment of this disclosure is shown.

[0023] Figure 2A flowchart illustrating a control method for a fuel system provided in an exemplary embodiment of this disclosure is shown.

[0024] Figure 3 This invention provides a mapping diagram showing the relationship between pump current and air-fuel ratio according to an exemplary embodiment of the present disclosure.

[0025] Figure 4 The graphs of relevant parameters are shown when the fuel system is controlled using the control method of the fuel system in the related art.

[0026] Figure 5 A graph of relevant parameters is shown when a fuel system is controlled using a control method for a fuel system provided in an exemplary embodiment of the present disclosure.

[0027] Figure 6 This illustration shows a schematic diagram of the structure of a control device for a fuel system provided in an exemplary embodiment of the present disclosure;

[0028] Figure 7 This is a schematic diagram of the structure of a computer device provided in an embodiment of this disclosure. Detailed Implementation

[0029] Unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” “third,” and similar terms used in this patent application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms “an” or “a” and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms “comprising” or “including” and similar terms mean that the elements or objects preceding “comprising” or “including” encompass the elements or objects listed following “comprising” or “including” and their equivalents, and do not exclude other elements or objects. The terms “connected” or “linked” and similar terms are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect.

[0030] To make the objectives, technical solutions, and advantages of this disclosure clearer, the embodiments of this disclosure will be described in further detail below with reference to the accompanying drawings.

[0031] Figure 1A flowchart illustrating a control method for a fuel system provided in an exemplary embodiment of this disclosure is shown. This method can be applied to any vehicle equipped with a wide-range oxygen sensor located before the three-way catalytic converter. The method can be executed by a controller on the vehicle, such as an ECU (Electronic Control Unit) or an MCU (Micro Control Unit). Figure 1 As shown, the method includes the following steps:

[0032] Step 101: Obtain the pump current flag of the wide-range oxygen sensor.

[0033] The pump current flag of the wide-range oxygen sensor has two states: valid or invalid. A valid pump current flag indicates that the pump current value is within the operating range of the wide-range oxygen sensor, while an invalid pump current flag indicates that the pump current value is outside the operating range of the wide-range oxygen sensor or that the pump current does not change within a certain time (10 seconds).

[0034] When the engine is functioning correctly and the wide-range oxygen sensor has no electrical faults, the pump current value of the oxygen sensor typically fluctuates within its operating range. Therefore, when the pump current value is outside the operating range of the wide-range oxygen sensor, it indicates an engine malfunction; conversely, if the pump current remains unchanged for a certain period, it indicates either an electrical fault in the oxygen sensor or an engine malfunction.

[0035] In this embodiment, the operating range of the wide-range oxygen sensor can be determined based on the performance of different wide-range oxygen sensors, and is not limited herein. For example, the pump current operating range of the wide-range oxygen sensor is [-3mA, 3mA].

[0036] Step 102: When the pump current flag is valid, determine the first air-fuel ratio value based on the pump current value of the wide-range oxygen sensor.

[0037] In step 102, the pump current value output by the wide-range oxygen sensor can be obtained first, and then the air-fuel ratio value corresponding to the pump current value output by the wide-range oxygen sensor can be used as the first air-fuel ratio value based on the correspondence between the pump current value and the air-fuel ratio value.

[0038] The correspondence between pump current value and air-fuel ratio value is pre-stored in the controller's memory. For example, the relationship between pump current value and air-fuel ratio value is stored in the controller's memory before the vehicle leaves the factory or before the method provided in this embodiment is executed.

[0039] Optionally, this correspondence can be obtained by testing the test object, which can be a whole vehicle or a vehicle engine. For example, the actual air-fuel ratio and pump current value of the test object during operation can be measured respectively, and the correspondence can be established based on the measured air-fuel ratio and pump current values.

[0040] Optionally, the pump current value of the oxygen sensor is acquired periodically, and the acquired pump current value is converted into a first air-fuel ratio value. Since the air-fuel ratio changes rapidly during vehicle operation, for example, it may change from 1 to 1.2 within one second, it is necessary to acquire the air-fuel ratio value in a timely manner to understand the operating status of the fuel system. Therefore, the period for acquiring the pump current value cannot exceed a first time threshold, which ranges from 1 to 30 seconds. For example, the first time threshold can be a value of 1 second, 5 seconds, 10 seconds, 30 seconds, etc.

[0041] Step 103: Control the air-fuel ratio of the fuel system according to the first air-fuel ratio value and the set air-fuel ratio range.

[0042] The defined air-fuel ratio range is used to indicate the range of air-fuel ratio values ​​during normal vehicle operation. In this embodiment of the disclosure, the air-fuel ratio range can be [0.6, 1.25].

[0043] An air-fuel ratio of [0.6, 0.88] results in an overly rich mixture, while an air-fuel ratio less than 0.6 easily produces a large amount of pollution. An air-fuel ratio of 0.88 results in maximum engine power. An air-fuel ratio of 1 is a stoichiometric mixture, achieving complete combustion. An air-fuel ratio of 1.11 is considered an economical mixture, maximizing fuel efficiency. An air-fuel ratio of (1.11, 1.25) results in an overly lean mixture, while an air-fuel ratio greater than 1.25 easily produces a large amount of pollution. Therefore, setting the air-fuel ratio range to [0.6, 1.25] covers all possible air-fuel ratios that may occur during normal vehicle operation. Controlling the air-fuel ratio of the fuel system according to this range can increase the stability of the fuel feedback control system.

[0044] In this embodiment, when the pump current flag is valid, a first air-fuel ratio value is determined based on the pump current value of a wide-range oxygen sensor; the air-fuel ratio of the fuel system is then controlled based on the first air-fuel ratio value and a set air-fuel ratio range. Specifically, when the pump current flag is valid, the air-fuel ratio of the fuel system is further controlled based on the first air-fuel ratio value and the set air-fuel ratio range. Since the relationship between the first air-fuel ratio value and the set air-fuel ratio range reflects whether the fuel system is operating normally, the air-fuel ratio of the fuel system can be controlled more accurately, thus effectively controlling pollutants in vehicle exhaust.

[0045] Figure 2 A flowchart illustrating a control method for a fuel system provided in an exemplary embodiment of this disclosure is shown. This method can be applied to any vehicle equipped with a wide-range oxygen sensor located before the three-way catalytic converter, and can be executed by a controller on the vehicle, such as an ECU or MCU. Figure 2 As shown, the method includes the following steps:

[0046] Step 201: Obtain the pump current value of the wide-range oxygen sensor.

[0047] Optionally, the wide-range oxygen sensor has a built-in pump current acquisition unit, which acquires the pump current of the wide-range oxygen sensor to output the pump current value; the ECU can receive the pump current value output by the pump current acquisition unit.

[0048] Step 202: Determine whether the pump current flag is valid based on the pump current value.

[0049] When the pump current flag is valid, proceed to step 203; when the pump current flag is invalid, proceed to step 206.

[0050] For details regarding the pump current flag, please refer to step 101.

[0051] Optionally, the validity of the pump current flag is determined by the relationship between the pump current value and the operating range of the wide-range oxygen sensor. If the current pump current value is within the operating range of the wide-range oxygen sensor, the pump current flag is considered valid. If the current pump current value is outside the operating range of the wide-range oxygen sensor or the pump current does not change within a certain time (10 seconds), the pump current flag is considered invalid.

[0052] Optionally, the pump current flag can be in level form. When the pump current flag is valid, the controller sets the level to high; when the pump current flag is invalid, the controller sets the level to low.

[0053] Step 203: Determine the first air-fuel ratio based on the pump current value.

[0054] In step 203, the air-fuel ratio corresponding to the pump current value can be determined as the first air-fuel ratio value according to the correspondence between the pump current value and the air-fuel ratio value. The relevant content of this correspondence is described in step 102, and will not be repeated here.

[0055] In one possible implementation, the correspondence between the pump current value and the air-fuel ratio value is a calibrated data table, which is stored in memory in tabular form. The air-fuel ratio value can be obtained based on the pump current value by querying this data table.

[0056] In another possible implementation, the correspondence between the pump current value and the air-fuel ratio value is a calibrated mapping (MAP) map, which is stored in memory in image form. The air-fuel ratio value can be obtained by querying the mapping map based on the pump current value.

[0057] Step 204: Determine whether the first air-fuel ratio value is within the set air-fuel ratio range; if the first air-fuel ratio value is within the set air-fuel ratio range, proceed to step 207; if the first air-fuel ratio value is outside the air-fuel ratio range, proceed to step 205.

[0058] Step 205: Determine whether the duration of the air-fuel ratio outside the set air-fuel ratio range reaches the first set duration.

[0059] If the duration of the first air-fuel ratio being outside the set air-fuel ratio range reaches the first set duration, proceed to step 206. If the duration of the first air-fuel ratio being outside the set air-fuel ratio range is less than the first set duration, proceed to step 207.

[0060] The specific value of the first set duration depends on the situation. In this embodiment of the disclosure, the value of the first set duration can be 5-20 seconds, for example, it can be 5s, 10s or 20s.

[0061] For details regarding the air-fuel ratio range, please refer to step 103, which will not be repeated here.

[0062] If the air-fuel ratio remains outside the set air-fuel ratio range for less than the first set time, it indicates that the air-fuel ratio may be due to momentary error, making it impossible to accurately determine whether the engine is malfunctioning. Only when the air-fuel ratio remains outside the set air-fuel ratio range for the first set time can an engine malfunction be confirmed.

[0063] Step 206: Control the fuel system using the set second air-fuel ratio value as the target air-fuel ratio.

[0064] Controlling the fuel system using a set second air-fuel ratio as the target air-fuel ratio is equivalent to using open-loop control. The target air-fuel ratio indicates the control objective of the fuel system, i.e., the desired air-fuel ratio value. The value of the second air-fuel ratio depends on the specific circumstances. For example, the range of the second air-fuel ratio value is 0.8-1.11, such as 0.8, 0.88, 1, or 1.11.

[0065] In this embodiment of the disclosure, there are two scenarios where the duration of the first air-fuel ratio being outside the set air-fuel ratio range reaches the first set duration. The first scenario is when the duration of the first air-fuel ratio being greater than 1.25 reaches the first set duration, in which case the amount of fuel in the mixture is too low, resulting in an overly lean mixture. The second scenario is when the duration of the first air-fuel ratio being less than 0.6 reaches the first set duration, in which case the amount of fuel in the mixture is too high, resulting in an overly rich mixture. Both scenarios indicate an abnormal air-fuel ratio.

[0066] During normal vehicle operation, the air-fuel ratio of the fuel system is typically controlled using closed-loop control. Under closed-loop control, the air-fuel ratio should be within the set range and reach the ideal value. Therefore, an abnormal air-fuel ratio indicates a malfunction in the closed-loop control process, suggesting an engine failure. In this case, closed-loop control needs to be discontinued, and open-loop control should be used to ensure the stability of the fuel system.

[0067] Optionally, step 206 includes the following three steps:

[0068] The first step is to obtain the engine's air intake volume.

[0069] Optionally, an air flow sensor is installed on the intake manifold of the vehicle engine, and the ECU can obtain the intake air volume through the air flow sensor.

[0070] The second step is to determine the first fuel injection quantity based on the set second air-fuel ratio and intake volume.

[0071] Alternatively, the fuel injection quantity is equal to the intake air quantity divided by the second air-fuel ratio. Therefore, the first fuel injection quantity is equal to the intake air quantity divided by the second air-fuel ratio.

[0072] The third step is to control the fuel injector to inject fuel according to the first fuel injection quantity.

[0073] Since the first injection quantity is determined based on the set second air-fuel ratio value when the air-fuel ratio of the fuel system is controlled by open-loop control, the air-fuel ratio of the fuel system can be close to the set second air-fuel ratio value. At the same time, it will not be affected by the failure of closed-loop control, thus ensuring the stability of the fuel system.

[0074] Optionally, the method further includes: controlling the air-fuel ratio of the fuel system in an open-loop control manner while controlling the heating of the wide-range oxygen sensor.

[0075] When using open-loop control to control the air-fuel ratio of the fuel system, it is not necessary to obtain the actual air-fuel ratio of the fuel system, that is, it is not necessary to obtain the pump current of the wide-range oxygen sensor. Therefore, it is not necessary to operate the wide-range oxygen sensor within the target operating range, and the heating of the wide-range oxygen sensor can be stopped.

[0076] Optionally, the method further includes: illuminating an engine malfunction indicator lamp in response to determining that the first air-fuel ratio value has been outside a set air-fuel ratio range for a first set duration. Illuminating the engine malfunction indicator lamp informs the user of the existence of the malfunction.

[0077] Optionally, before performing step 202, it is necessary to determine whether the wide-range oxygen sensor is fault-free. Step 202 and subsequent steps can only be performed if the wide-range oxygen sensor is fault-free.

[0078] In this embodiment of the disclosure, the method further includes determining whether a wide-range oxygen sensor is faulty. The fault type of the wide-range oxygen sensor includes at least one of electrical faults and heating faults. If the wide-range oxygen sensor has either a heating fault or an electrical fault, the wide-range oxygen sensor is determined to be faulty; this is because if an electrical fault exists, the wide-range oxygen sensor cannot function properly; if a heating fault exists, the temperature of the wide-range oxygen sensor is not near a first temperature threshold, and the pump current value output by the wide-range oxygen sensor is inaccurate. If the wide-range oxygen sensor has neither a heating fault nor an electrical fault, it is determined that the wide-range oxygen sensor is not faulty.

[0079] In this embodiment of the disclosure, the pump current value obtained based on the wide-range oxygen sensor can only be considered an accurate pump current value if the wide-range oxygen sensor is fault-free, thereby enabling corresponding control based on the pump current value and ensuring the accuracy of the fuel system control method.

[0080] Optionally, the method for determining whether a wide-range oxygen sensor has an electrical fault includes: obtaining the difference between the highest and lowest values ​​of the pump current within a first time period to obtain a first detection result; and obtaining the difference between the highest and lowest values ​​of the pump current within a second time period to obtain a second detection result. If the difference between the first and second detection results is less than or equal to a first current threshold, it indicates that the pump current fluctuations within the first and second time periods are not significantly different, which means the wide-range oxygen sensor has no electrical fault. If the difference between the first and second detection results is greater than the first current threshold, it indicates that the pump current fluctuations within the first and second time periods differ excessively, suggesting abnormal fluctuations in the pump current, which indicates an electrical fault in the wide-range oxygen sensor.

[0081] The first current threshold is determined based on the performance of different wide-range oxygen sensors; the first time period and the second time period are two different time periods of equal length within a continuous time period, and the specific values ​​are determined based on the actual situation, without being limited here.

[0082] For example, the first current threshold value ranges from 1 to 2 mA, such as 1 mA, 1.5 mA, or 2 mA. The first time period and the second time period range from 30 seconds to 5 minutes, such as 30 seconds, 1 minute, 2 minutes, 3 minutes, or 5 minutes.

[0083] Optionally, the method for determining whether a wide-range oxygen sensor has a heating fault includes: under closed-loop heating control of the wide-range oxygen sensor, obtaining the average temperature of the wide-range oxygen sensor within a third time period to obtain a third detection result. The third detection result is compared with a first temperature threshold. If the difference between the third detection result and the first temperature threshold is less than or equal to a second temperature threshold, it indicates that the temperature of the wide-range oxygen sensor is near its optimal operating temperature, and the wide-range oxygen sensor has no heating fault. If the difference between the third detection result and the first temperature threshold is greater than the second temperature threshold, it indicates that the temperature of the wide-range oxygen sensor deviates from its optimal operating temperature, and the wide-range oxygen sensor has a heating fault.

[0084] The first temperature threshold is used to indicate the optimal operating temperature of the wide-range oxygen sensor. The first and second temperature thresholds are determined according to the performance of different wide-range oxygen sensors. The specific value of the third time period is determined according to the actual situation and is not limited here.

[0085] For example, the first temperature threshold ranges from 600 to 750 degrees Celsius, such as 600°C, 700°C, or 750°C. The second temperature threshold ranges from 15 to 30 degrees Celsius, such as 15°C, 20°C, or 30°C. The third time period ranges from 30 seconds to 5 minutes, such as 30 seconds, 1 minute, 2 minutes, 3 minutes, or 5 minutes.

[0086] Step 207: Use closed-loop control to control the air-fuel ratio of the fuel system so that the air-fuel ratio of the fuel system reaches the set third air-fuel ratio value.

[0087] In closed-loop control, the feedback information is the difference between the first and third air-fuel ratios, and the controlled object is the air-fuel ratio of the fuel system. That is, the air-fuel ratio of the fuel system is controlled based on the difference between the first and third air-fuel ratios.

[0088] The value of the third air-fuel ratio is determined based on the actual situation and is not specifically limited. For example, the range of the third air-fuel ratio is 0.8-1.11, such as 0.8, 0.88, 1 or 1.11.

[0089] Optionally, step 207 may include the following four steps.

[0090] The first step is to determine the fuel adjustment coefficient based on the difference between the first and third air-fuel ratios.

[0091] Optionally, when the first air-fuel ratio is greater than the third air-fuel ratio, the current value of the fuel adjustment coefficient is added to the first value; when the first air-fuel ratio is less than the third air-fuel ratio, the current value of the fuel adjustment coefficient is subtracted from the second value. Here, the current value refers to the fuel adjustment coefficient corresponding to the first air-fuel ratio. The first and second values ​​are set step sizes, such as 0.1; or, the first value is determined based on the difference between the first and third air-fuel ratios, for example, the first value is proportional to the difference between the first and third air-fuel ratios.

[0092] The fuel adjustment coefficient is limited by an upper and lower limit to ensure that the fuel system does not adjust the injection quantity too much or too little at once. For example, the adjustment range of the fuel adjustment coefficient is [0.6, 1.25]. If the adjustment of the fuel adjustment coefficient exceeds the adjustment range, the fuel adjustment coefficient will be the lower limit value when it exceeds the lower limit, and the fuel adjustment coefficient will be the upper limit value when it exceeds the upper limit.

[0093] The second step is to determine the second fuel injection quantity corresponding to the first air-fuel ratio.

[0094] Optionally, the controller's memory stores the correspondence between time, air-fuel ratio, and fuel injection quantity. The controller only needs to determine the moment when the first air-fuel ratio is obtained, and then query the memory for the corresponding fuel injection quantity at that moment to obtain the second fuel injection quantity.

[0095] The third step is to adjust the second fuel injection quantity based on the feedback information to obtain the third fuel injection quantity.

[0096] Optionally, the third injection quantity is obtained by multiplying the fuel adjustment coefficient by the second injection quantity.

[0097] The fourth step is to control the injector to inject fuel according to the third injection quantity.

[0098] Optionally, the method further includes: after controlling the fuel system with a set second air-fuel ratio as the target air-fuel ratio, after a third set time, controlling the wide-range oxygen sensor to heat to a first temperature threshold; determining whether the duration of the second air-fuel ratio value corresponding to the pump current value output by the wide-range oxygen sensor within the set air-fuel ratio range reaches the second set time; if the duration of the second air-fuel ratio value within the set air-fuel ratio range reaches the second set time, then step 207 is executed; if the duration of the second air-fuel ratio value within the set air-fuel ratio range does not reach the second set time, or if the second air-fuel ratio value is not within the set air-fuel ratio range, then controlling the wide-range oxygen sensor to stop heating, and after waiting for the third set time again, re-determining whether the duration of the second air-fuel ratio value corresponding to the pump current value output by the wide-range oxygen sensor within the set air-fuel ratio range reaches the second set time.

[0099] The method for determining whether the duration of the second air-fuel ratio value corresponding to the pump current value output by the wide-range oxygen sensor within the set air-fuel ratio range reaches the second set duration is similar to steps 203 to 205, and detailed description is omitted here.

[0100] The specific values ​​of the second and third set durations are determined based on actual circumstances and are not limited here. In this embodiment, the value of the second set duration ranges from 5 to 20 seconds, for example, it can be 5 seconds, 10 seconds, or 20 seconds. The value of the third set duration ranges from 30 to 120 minutes, for example, it can be 30 minutes, 60 minutes, 90 minutes, or 120 minutes.

[0101] Optionally, controlling the heating of the wide-range oxygen sensor to a first temperature threshold includes the following steps.

[0102] The first step is to obtain the first temperature value of the current wide-range oxygen sensor.

[0103] The wide-range oxygen sensor has a built-in temperature sensor that detects the current temperature of the oxygen sensor and outputs a temperature value. The ECU can obtain the first temperature value of the wide-range oxygen sensor by acquiring the temperature value output by this temperature sensor.

[0104] The second step is to determine the difference between the first temperature value and the first temperature threshold, which is the temperature feedback information.

[0105] The third step is to determine the first heating power corresponding to the current temperature value.

[0106] Optionally, the heating of the wide-range oxygen sensor is mainly achieved by a built-in heating device, and the controller controls the temperature of the wide-range oxygen sensor by controlling the power applied to the heating device. The controller's memory records the wide-range oxygen sensor temperature and the corresponding heating power per second.

[0107] Therefore, the controller only needs to determine the time corresponding to the first temperature value, and then query the memory for the heating power of the heating device corresponding to that time to determine the first heating power.

[0108] The fourth step is to adjust the first heating power based on the temperature feedback information to obtain the second heating power.

[0109] When the first temperature value is greater than the first temperature threshold, the temperature feedback information is to reduce the first heating power to obtain the second heating power. When the first temperature value is less than the first temperature threshold, the temperature feedback information is to increase the first heating power to obtain the second heating power. The actual reduction or increase in power value depends on the actual situation.

[0110] For example, the first temperature value is 600 degrees Celsius, the first temperature threshold is 700 degrees Celsius, the first temperature value is obtained at the 23rd second, and the heating power at that moment is 1000W. Since the first temperature value is less than the first temperature threshold, the heating power is controlled to become 1200W.

[0111] The fifth step is to control the heating device to heat the wide-range oxygen sensor with the second heating power so that the temperature of the wide-range oxygen sensor reaches the first temperature threshold.

[0112] In this embodiment, when the pump current flag is valid, a first air-fuel ratio value is determined based on the pump current value of a wide-range oxygen sensor; the air-fuel ratio of the fuel system is then controlled based on the first air-fuel ratio value and a set air-fuel ratio range. Specifically, when the pump current flag is valid, the air-fuel ratio of the fuel system is further controlled based on the first air-fuel ratio value and the set air-fuel ratio range. Since the relationship between the first air-fuel ratio value and the set air-fuel ratio range reflects whether the fuel system is operating normally, the air-fuel ratio of the fuel system can be controlled more accurately, thus effectively controlling pollutants in vehicle exhaust.

[0113] Furthermore, when the pump current flag is valid, the system determines whether to enter closed-loop control or open-loop control of the fuel system based on whether the first air-fuel ratio value is within the set air-fuel ratio range and the duration of the first air-fuel ratio value outside the set range. This avoids exceeding the standard of vehicle exhaust pollutants when closed-loop control is still performed when the pump current flag is valid but the operating state of the fuel system is abnormal.

[0114] Furthermore, after controlling the fuel system with a set second air-fuel ratio as the target air-fuel ratio, a third set time is elapsed. The system then determines whether the second air-fuel ratio value corresponding to the pump current value output by the wide-range oxygen sensor has remained within the set air-fuel ratio range for the duration specified in the second set time, thereby determining whether the fault has been cleared. If the fault has been cleared, closed-loop control is used to control the air-fuel ratio of the fuel system. Since closed-loop control is more accurate than open-loop control, it can maintain the air-fuel ratio value near the second air-fuel ratio value when the fuel system is operating normally, thus improving the control efficiency of the fuel control system.

[0115] Figure 3 A mapping diagram showing the relationship between pump current and air-fuel ratio provided in an exemplary embodiment of this disclosure is shown. See also Figure 3The set air-fuel ratio range is the air-fuel ratio value corresponding to points A to B, which is [0.6-1.25]; the operating range of the wide-range oxygen sensor is [-2.5mA, 2.5mA]. The pump current value corresponding to point C is 0.8, that is, the pump current value corresponding to point C is within the operating range of the wide-range oxygen sensor, meaning the pump current flag is valid. However, the air-fuel ratio value corresponding to point C is 1.5, which is outside the set air-fuel ratio range.

[0116] Figure 4 The diagram illustrates the graphs of relevant parameters when controlling a fuel system using a fuel system control method from the related art, using an example of a set air-fuel ratio range of [0.6, 1.25] and a second air-fuel ratio value of 1. See also... Figure 4 , Figure 4 It includes 5 curves, of which 401 is the air-fuel ratio curve, 402 is the pump current curve, and it can be seen from the figure that 401 and 402 have a corresponding relationship; 403 is the fuel adjustment coefficient curve; 404 is the pump current flag curve, which includes high level and low level. When the level is high, the pump current flag is valid, and when the level is low, the pump current flag is invalid; 405 is the air-fuel ratio control mode curve, which includes high level and low level. When the level is high, the air-fuel ratio of the fuel system is controlled by closed-loop control mode, and when the level is low, the air-fuel ratio of the fuel system is controlled by open-loop control mode.

[0117] At time T1, which is the 22nd second, the pump current flag curve 404 is at a low level, indicating that the pump current flag is invalid; the air-fuel ratio control mode curve 405 is at a low level, meaning that it is in open-loop control mode at this time, and the fuel adjustment coefficient is 1. At time T2, which is the 46th second, the pump current flag curve 404 is at a high level, indicating that the pump current flag is valid; the air-fuel ratio control mode curve 405 is at a high level, meaning that it is in closed-loop control mode at this time. Theoretically, the air-fuel ratio value should be near the second air-fuel ratio value of 1 at this time; however, as can be seen from the figure, the air-fuel ratio value at this time is 1.387, which is far from the second air-fuel ratio value and exceeds the set air-fuel ratio range. At this time, the pump current value is 0.727, which is still within the valid range of the pump current flag. Because the system is in closed-loop control and it detects that the air-fuel ratio is significantly deviating from the second air-fuel ratio, it sets the fuel adjustment coefficient to its maximum value of 1.25. However, this coefficient is insufficient to restore the air-fuel ratio to the second value; as can be seen, the air-fuel ratio remains significantly deviated after 46 seconds. The continued operation of the fuel system at this air-fuel ratio results in an excessively lean mixture and excessive emissions of pollutants from the vehicle's exhaust.

[0118] Figure 5 A graph showing the relevant parameters when a fuel system is controlled using a control method for a fuel system provided in an exemplary embodiment of this disclosure. See also Figure 5 , Figure 5 It includes 5 curves, of which 501 is the air-fuel ratio curve, 502 is the pump current curve, and it can be seen from the figure that 501 and 502 have a corresponding relationship; 503 is the fuel adjustment coefficient curve; 504 is the pump current flag curve, which includes high level and low level. When the level is high, the pump current flag is valid, and when the level is low, the pump current flag is invalid; 505 is the air-fuel ratio control mode curve, which includes high level and low level. When the level is high, the air-fuel ratio of the fuel system is controlled by closed-loop control mode, and when the level is low, the air-fuel ratio of the fuel system is controlled by open-loop control mode.

[0119] At time T3, which is 62 seconds, the following occurred: Figure 4 A similar problem at time T2, but different. Figure 4 Because the fuel system control method provided in this embodiment is adopted, the system identifies the problem at 74 seconds (i.e., after a first set time period) and performs corresponding control between 74 and 79 seconds. Specifically, in response to the determination that the air-fuel ratio value is outside the set air-fuel ratio range for a duration longer than the first set time period, an open-loop control method is used to control the air-fuel ratio of the fuel system. Figure 5 The air-fuel ratio control curve 505 goes low, and the fuel adjustment coefficient curve 503 is set to 1. In fact, at 74 seconds, the open-loop control method should have simultaneously controlled the air-fuel ratio and brought it back to normal. However, due to the lag in the system's detection of closed-loop control, this resulted in… Figure 5 This manifests as a situation where the air-fuel ratio first decreases before closed-loop control is implemented. By the time the air-fuel ratio reaches time T4, it has recovered to the second air-fuel ratio, thus preventing the vehicle from using an air-fuel ratio deviating from the ideal value for control and effectively reducing the emission of pollutants from vehicle exhaust.

[0120] The following are device embodiments of this application. For details not described in detail in the device embodiments, please refer to the above method embodiments.

[0121] Figure 6 A schematic diagram of a control device for a fuel system provided in an exemplary embodiment of this disclosure is shown. See also Figure 6 The control device 600 of the fuel system includes: an acquisition module 601, a determination module 602, and a first control module 603.

[0122] The acquisition module 601 is used to acquire the pump current flag bit of the wide-range oxygen sensor; the determination module 602 is used to determine the first air-fuel ratio value based on the pump current value of the wide-range oxygen sensor when the pump current flag bit is valid; the first control module 603 is used to control the air-fuel ratio of the fuel system based on the first air-fuel ratio value and the set air-fuel ratio range.

[0123] Optionally, the first control module 603 is further configured to control the fuel system with a set second air-fuel ratio as the target air-fuel ratio in response to determining that the first air-fuel ratio value is outside the air-fuel ratio range for a first set time.

[0124] Optionally, the first control module 603 is further configured to, in response to determining that the first air-fuel ratio value is within the air-fuel ratio range, or in response to determining that the duration of the first air-fuel ratio value being outside the air-fuel ratio range is less than a first set duration, control the air-fuel ratio of the fuel system in a closed-loop control manner, so that the air-fuel ratio of the fuel system reaches a set third air-fuel ratio value.

[0125] Optionally, the first control module 603 is further configured to, after controlling the fuel system with the set second air-fuel ratio as the target air-fuel ratio, in response to determining that the first air-fuel ratio value has been within the air-fuel ratio range for a second set time, control the air-fuel ratio of the fuel system in a closed-loop control manner so that the air-fuel ratio of the fuel system reaches a set third air-fuel ratio value.

[0126] Optionally, the device further includes a heating control module 604 and a second control module 605. The heating control module 604 is configured to control the wide-range oxygen sensor to stop heating in response to determining that the duration for which the first air-fuel ratio value is outside the air-fuel ratio range reaches a first set duration. The second control module 605 is configured to control the fuel system with a set second air-fuel ratio value as the target air-fuel ratio when the pump current flag is invalid.

[0127] In this embodiment, when the pump current flag is active, a first air-fuel ratio value is determined based on the pump current value of a wide-range oxygen sensor; the air-fuel ratio of the fuel system is controlled based on the first air-fuel ratio value and a set air-fuel ratio range. This effectively identifies and controls situations where the air-fuel ratio of the fuel system is abnormally high or low, thereby increasing the stability of the fuel feedback control system and enabling effective control of pollutants in vehicle exhaust.

[0128] It should be noted that the fuel system control device provided in the above embodiments is only illustrated by the division of the above functional modules. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. In addition, the fuel system control device and the fuel system control method embodiments provided in the above embodiments belong to the same concept, and the specific implementation process can be found in the method embodiments, which will not be repeated here.

[0129] Figure 7This is a schematic diagram of the structure of a computer device provided in an embodiment of this disclosure. Figure 7 As shown, the computer device 700 includes a processor 701 and a memory 702.

[0130] Processor 701 may include one or more processing cores, such as a quad-core processor, an octa-core processor, etc. Processor 701 may be implemented using at least one hardware form selected from DSP (Digital Signal Processing), FPGA (Field-Programmable Gate Array), and PLA (Programmable Logic Array). Processor 701 may also include a main processor and a coprocessor. The main processor, also known as a CPU (Central Processing Unit), is used to process data in the wake-up state; the coprocessor is a low-power processor used to process data in the standby state. In some embodiments, processor 701 may integrate a GPU (Graphics Processing Unit), which is responsible for rendering and drawing the content to be displayed on the screen. In some embodiments, processor 701 may also include an AI (Artificial Intelligence) processor, which is used to handle computational operations related to machine learning.

[0131] The memory 702 may include one or more computer-readable storage media, which may be non-transitory. The memory 702 may also include high-speed random access memory and non-volatile memory, such as one or more disk storage devices or flash memory devices. In some embodiments, the non-transitory computer-readable storage media in the memory 702 are used to store at least one instruction, which is executed by the processor 701 to implement the fuel system control method provided in the embodiments of this disclosure.

[0132] Those skilled in the art will understand that Figure 7 The structure shown does not constitute a limitation on the computer device 700, and may include more or fewer components than shown, or combine certain components, or use different component arrangements.

[0133] This disclosure also provides a non-transitory computer-readable storage medium, wherein when instructions in the storage medium are executed by a processor of a computer device, the computer device is able to execute the fuel system control method provided in this disclosure.

[0134] This disclosure also provides a computer program product, including a computer program / instructions, which, when executed by a processor, implement the fuel system control method provided in this disclosure.

[0135] The above description is merely an optional embodiment of this disclosure and is not intended to limit this disclosure. Any modifications, equivalent switching, improvements, etc., made within the spirit and principles of this disclosure should be included within the protection scope of this disclosure.

Claims

1. A control method for a fuel system, characterized in that, The method includes: Under the condition that the wide-range oxygen sensor is fault-free, obtain the pump current flag bit of the wide-range oxygen sensor; When the pump current flag is valid, the first air-fuel ratio value is determined based on the pump current value of the wide-range oxygen sensor. In response to determining that the first air-fuel ratio value is outside the set air-fuel ratio range for a first set time, the engine intake air volume is obtained, and a first fuel injection quantity is determined according to the set second air-fuel ratio value and the intake air volume. The fuel injector is controlled to inject fuel according to the first fuel injection quantity. The first fuel injection quantity is equal to the intake air volume divided by the second air-fuel ratio value. The set air-fuel ratio range is used to indicate the range of air-fuel ratio values ​​when the vehicle is running normally. After the injector injects fuel according to the first injection quantity, in response to the determination that the first air-fuel ratio value is within the air-fuel ratio range for a second set time, the air-fuel ratio of the fuel system is controlled by closed-loop control so that the air-fuel ratio of the fuel system reaches a set third air-fuel ratio value.

2. The method according to claim 1, characterized in that, The step of controlling the air-fuel ratio of the fuel system based on the first air-fuel ratio value and the set air-fuel ratio range further includes: In response to determining that the first air-fuel ratio value is within the air-fuel ratio range, or in response to determining that the duration of the first air-fuel ratio value being outside the air-fuel ratio range is less than a first set duration, the air-fuel ratio of the fuel system is controlled in a closed-loop control manner so that the air-fuel ratio of the fuel system reaches a set third air-fuel ratio value.

3. The method according to claim 1, characterized in that, The method further includes: In response to determining that the first air-fuel ratio value is outside the air-fuel ratio range for a period of time that reaches the first set time, the wide-range oxygen sensor is controlled to stop heating.

4. The method according to any one of claims 1 to 3, characterized in that, The method further includes: When the pump current flag is invalid, the fuel system is controlled using the set second air-fuel ratio value as the target air-fuel ratio.

5. A control device for a fuel system, characterized in that, The device includes: The acquisition module is used to acquire the pump current flag bit of the wide-range oxygen sensor when the wide-range oxygen sensor is fault-free. The determination module is used to determine a first air-fuel ratio value based on the pump current value of the wide-range oxygen sensor when the pump current flag is valid. The first control module is configured to respond to the determination that when the first air-fuel ratio value is outside the set air-fuel ratio range for a first set time, it acquires the intake air volume of the engine, determines the first fuel injection quantity based on the set second air-fuel ratio value and the intake air volume, and controls the injector to inject fuel according to the first fuel injection quantity. The first fuel injection quantity is equal to the intake air volume divided by the second air-fuel ratio value. The set air-fuel ratio range is used to indicate the range of air-fuel ratio values ​​when the vehicle is running normally. After the injector injects fuel according to the first injection quantity, in response to the determination that the first air-fuel ratio value is within the air-fuel ratio range for a second set time, the air-fuel ratio of the fuel system is controlled by closed-loop control so that the air-fuel ratio of the fuel system reaches a set third air-fuel ratio value.

6. A computer device, characterized in that, The computer device includes a memory and a processor, wherein the memory stores at least one computer program, which is loaded and executed by the processor to implement the method according to any one of claims 1 to 4.

7. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores at least one computer program, which is loaded and executed by a processor to implement the method of any one of claims 1 to 4.

8. A computer program product comprising a computer program / instructions, characterized in that, When the computer program / instructions are executed by the processor, they implement the method described in any one of claims 1 to 4.

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