Oxygen sensor control method, controller, vehicle and storage medium

Abstract

The invention relates to an oxygen sensor control method, a controller, a vehicle and a storage medium, and belongs to the technical field of oxygen sensor control, an oxygen sensor is mounted on an exhaust pipe of an engine, and the method comprises the steps that first accumulated exhaust heat and first wall surface temperature at the mounting position of the oxygen sensor are obtained; judging whether the first accumulated exhaust heat is greater than an exhaust heat threshold value and whether the first wall surface temperature is greater than a dew point temperature; and if the first accumulated exhaust heat is larger than the exhaust heat threshold value and the first wall surface temperature is larger than the dew point temperature, an oxygen sensor is started. According to the method, whether condensate water at the mounting position of the oxygen sensor is completely evaporated or not is judged by comparing the first accumulated exhaust heat with the exhaust heat threshold value, and whether condensate water is formed at the position or not is judged by comparing the first wall surface temperature with the dew point temperature; when it is determined that condensate water at the installation position of the oxygen sensor is completely evaporated and no condensate water is formed at the installation position, the oxygen sensor is started; the damage risk of the oxygen sensor can be reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of oxygen sensor control, and in particular to an oxygen sensor control method, a controller, a vehicle and a storage medium. Background Art

[0002] The wide-range oxygen sensor is a sensor used to measure the oxygen content in the engine exhaust. The air-fuel ratio is closed-loop controlled by measuring the oxygen content in the exhaust gas, thereby optimizing combustion efficiency and reducing emissions. The wide-range oxygen sensor is usually installed on the engine exhaust pipe. It is generally composed of a metal shell, a ceramic body, an oxygen ion conductive layer, an electrode, etc. When the temperature of the wide-range oxygen sensor is within the range of 780 ± 10℃, the sensor's working performance is optimal, so it is necessary to control the wide-range oxygen sensor to heat to the operating temperature. However, if there is condensed water at the installation location of the wide-range oxygen sensor, direct and rapid heating to the operating temperature at this time is likely to cause the ceramic components of the wide-range oxygen sensor to be damaged and cracked by the thermal shock of the condensed water droplets.

[0003] The related technology determines whether there is condensed water in the exhaust pipe by comparing the exhaust heat in the engine exhaust pipe with the exhaust heat threshold. If there is no condensed water, the wide-range oxygen sensor is turned on to avoid the wide-range oxygen sensor from being subjected to thermal shock from condensed water droplets. However, this method does not comprehensively consider the occurrence of condensed water at the installation position of the wide-range oxygen sensor, resulting in inaccurate control of the oxygen sensor. Summary of the invention

[0004] In view of this, it is necessary to provide an oxygen sensor control method, controller, vehicle and storage medium to solve the problem that the related technology does not fully consider the occurrence of condensed water at the installation position of the wide-range oxygen sensor, resulting in inaccurate control of the oxygen sensor.

[0005] In order to solve the above problems, in a first aspect, the present invention provides an oxygen sensor control method, wherein the oxygen sensor is installed on an exhaust pipe of an engine, and the method comprises: Acquire a first accumulated exhaust heat and a first wall temperature at the oxygen sensor installation position; determining whether the first accumulated exhaust heat is greater than an exhaust heat threshold, and whether the first wall temperature is greater than a dew point temperature; If the first accumulated exhaust heat is greater than the exhaust heat threshold and the first wall temperature is greater than the dew point temperature, the oxygen sensor is turned on.

[0006] Optionally, the exhaust pipe further includes a catalyst; and obtaining the first accumulated exhaust heat at the installation position of the oxygen sensor includes: The first accumulated exhaust heat at the oxygen sensor installation position is determined by the following formula: ; in, is the first accumulated exhaust heat at the oxygen sensor installation position at the current moment; is the second accumulated exhaust heat at the oxygen sensor installation position at the last moment; is the change in exhaust heat at the oxygen sensor installation position at the current moment; When the engine is in a stopped state, ,in, is the first wall temperature at the oxygen sensor installation position at the current moment; is the second wall temperature at the oxygen sensor installation position at the last moment; is the heat coefficient corresponding to the temperature change; When the engine is in operation, ,in, is the first exhaust gas mass flow in the exhaust pipe at the current moment; is the exhaust gas temperature in the exhaust pipe at the current moment; represents an exhaust temperature threshold value that brings heat to the installation position of the oxygen sensor; is the exhaust gas specific heat capacity; is an influencing factor on the change in the exhaust heat when the catalyst is running.

[0007] Optionally, the exhaust heat threshold is determined based on a third wall temperature at the oxygen sensor installation position when the engine is started, an engine cooling water temperature, and a number of repeated engine starts.

[0008] Optionally, the method further includes: When the oxygen sensor is turned on, the stall information of the engine is determined in real time; Determining whether the stall information meets a preset condition; If the stall information satisfies the preset condition, the oxygen sensor is turned off, and the process returns to the step of obtaining the accumulated exhaust heat and the wall temperature at the oxygen sensor installation position.

[0009] Optionally, the stall information of the engine includes: a supply relationship characterization value, where the supply relationship characterization value is a ratio of the combustion heat of the engine to a corresponding coefficient of the second exhaust mass flow in the exhaust pipe; and the judging whether the stall information satisfies a preset condition includes: Determining whether the supply relationship characterization value is less than a preset characterization threshold; If the stall information satisfies a preset condition, the oxygen sensor is turned off, and the step of returning to obtain the cumulative exhaust heat and the wall temperature at the oxygen sensor installation position includes: If the supply relationship characterization value is less than the preset characterization threshold, the oxygen sensor is turned off, and the process returns to the step of obtaining the accumulated exhaust heat and the wall temperature at the oxygen sensor installation position.

[0010] Optionally, the preset characterization threshold is determined according to the ambient temperature.

[0011] Optionally, the method further includes: When the oxygen sensor is turned on, the third wall temperature at the oxygen sensor installation position is obtained in real time; determining whether the third wall temperature is less than the dew point temperature; If the third wall temperature is lower than the dew point temperature, the oxygen sensor is turned off, and the process returns to the step of obtaining the cumulative exhaust heat and the wall temperature at the oxygen sensor installation position.

[0012] In a second aspect, the present invention further provides a controller for executing the steps in any one of the above oxygen sensor control methods.

[0013] In a third aspect, the present invention further provides a vehicle, comprising an oxygen sensor, an engine, an exhaust pipe and the above-mentioned controller; wherein the oxygen sensor is installed on the exhaust pipe of the engine.

[0014] In a fourth aspect, the present invention further provides a computer-readable storage medium for storing a computer-readable program, wherein the program or instructions, when executed by a processor, can implement the steps in any one of the above-mentioned oxygen sensor control methods.

[0015] The beneficial effects of the present invention are: The present invention determines whether all condensed water at the oxygen sensor installation position has evaporated by comparing the first accumulated exhaust heat at the oxygen sensor installation position with the exhaust heat threshold, and determines whether condensed water will still form at the oxygen sensor installation position by comparing the first wall temperature at the oxygen sensor installation position with the dew point temperature. When it is determined that the first accumulated exhaust heat is greater than the exhaust heat threshold, and the first wall temperature is greater than the dew point temperature, that is, it is determined that all condensed water at the oxygen sensor installation position has evaporated and no condensed water will be formed at the oxygen sensor, the oxygen sensor is turned on. The risk of the oxygen sensor being subjected to thermal shock from condensed water when turned on can be reduced, so that the oxygen sensor can work normally.

[0016] The present invention controls the opening of the oxygen sensor by comprehensively considering the evaporation of condensed water at the installation position of the oxygen sensor and the formation of condensed water, which is more comprehensive and can more effectively reduce the risk of damage to the oxygen sensor after it is opened. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic diagram of an engine after-treatment emission system provided by the present invention; Figure 2 A schematic flow chart of an embodiment of an oxygen sensor control method provided by the present invention; Figure 3 A flow chart of another embodiment of the oxygen sensor control method provided by the present invention; Figure 4 A schematic diagram of a dew point state control flow of an oxygen sensor provided by the present invention; 10-engine; 20-electronic control unit; 30-oxygen sensor; 40-exhaust temperature sensor; 50-three-way catalytic converter. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0019] In the description of the embodiments of the present invention, unless otherwise specified, "multiple" means two or more. The descriptions of "first", "second", etc. involved in the embodiments of the present invention are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the technical features defined as "first" and "second" may explicitly or implicitly include at least one of the features.

[0020] 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 invention. 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.

[0021] Reference Figure 1 , shows a schematic diagram of an engine post-treatment emission system provided by the present invention. The system includes an engine 10; an electronic control unit (ECU) 20; a wide-range oxygen sensor 30; an exhaust temperature sensor 40 and a three-way catalytic converter (TWC) 50.

[0022] Among them, the electronic control unit 20 is used to obtain various information of the engine, calculate and monitor the behavior. In this embodiment, the electronic control unit 20 is mainly used to realize the following functions: ① obtain the current working condition information of the engine, which includes exhaust mass flow, exhaust temperature at the installation position of the wide-range oxygen sensor, engine speed and ambient temperature; ② calculate the wall temperature, dew point temperature, cumulative exhaust heat, exhaust heat threshold, combustion heat and exhaust mass flow corresponding coefficient ratio at the installation position of the wide-range oxygen sensor according to the engine working condition information; ③ judge the dew point state at the installation position of the wide-range oxygen sensor according to the calculated wall temperature, dew point temperature, cumulative exhaust heat, exhaust heat threshold, combustion heat and exhaust mass flow corresponding coefficient ratio; ④ control the opening and closing of the wide-range oxygen sensor according to the dew point state at the installation position of the wide-range oxygen sensor.

[0023] The wide-range oxygen sensor 30 is used to detect the oxygen content in the exhaust pipe of the engine to obtain the actual fuel-air ratio of the current working condition and perform closed-loop correction on the fuel.

[0024] The exhaust temperature sensor 40 is used to detect the exhaust temperature at the installation location of the wide-range oxygen sensor, so as to calculate the relevant signal of the dew point diagnosis.

[0025] Reference Figure 2 , shows a flow chart of an embodiment of an oxygen sensor control method provided by the present invention, the oxygen sensor is installed on the exhaust pipe of the engine, and the method includes: S101, obtaining a first accumulated exhaust heat amount and a first wall temperature at an oxygen sensor installation position.

[0026] The oxygen sensor may be a wide-range oxygen sensor. The first accumulated exhaust heat and the first wall temperature at the oxygen sensor installation location may be calculated based on the engine operating information. For example, when the engine is running, the first wall temperature at the oxygen sensor installation location may be calculated based on the exhaust temperature at the oxygen sensor installation location, the exhaust mass flow rate, the vehicle speed, the ambient temperature and other conditions, taking into account the heat exchange between the exhaust gas and the exhaust pipe wall, and the heat exchange between the exhaust pipe wall and the external environment; when the engine is stopped, no exhaust gas passes through the exhaust pipe. At this time, the first wall temperature at the oxygen sensor installation location may be calculated based on the stop time, the ambient temperature and other conditions, taking into account the heat exchange between the oxygen sensor wall and the external environment.

[0027] The first wall temperature can also be directly detected by a temperature detection device.

[0028] S102, determining whether a first accumulated exhaust heat amount is greater than an exhaust heat threshold, and whether a first wall temperature is greater than a dew point temperature.

[0029] The exhaust heat threshold value may be determined based on the third wall temperature at the oxygen sensor installation position when the engine is started, the engine cooling water temperature, and the number of repeated engine starts.

[0030] The dew point temperature is the temperature at which the water vapor in the gas reaches saturation under a certain pressure. The dew point temperature can be obtained by checking the MAP based on the exhaust pressure and exhaust temperature at the oxygen sensor installation location.

[0031] S103: If the first accumulated exhaust heat is greater than the exhaust heat threshold and the first wall temperature is greater than the dew point temperature, the oxygen sensor is turned on.

[0032] When the first accumulated exhaust heat at the oxygen sensor installation position is greater than the exhaust heat threshold, there is no condensed water at the oxygen sensor installation position; when the first accumulated exhaust heat at the oxygen sensor installation position is less than the exhaust heat threshold, there is condensed water at the oxygen sensor installation position.

[0033] When the first wall temperature at the oxygen sensor installation position is greater than the dew point temperature, no condensed water will form at the oxygen sensor installation position; when the temperature at the sensor installation position is less than the dew point temperature, water vapor in the exhaust gas will form condensed water in the exhaust pipe.

[0034] Therefore, when the first accumulated exhaust heat is greater than the exhaust heat threshold and the first wall temperature is greater than the dew point temperature, the dew point state at this time is determined to be the dew point passing state, and the oxygen sensor is turned on; and when the first accumulated exhaust heat is less than or equal to the exhaust heat threshold, or the first wall temperature is less than or equal to the dew point temperature, the dew point state at this time is determined to be the dew point not passing state, and the oxygen sensor is kept in the closed state.

[0035] The present invention determines whether all condensed water at the oxygen sensor installation position has evaporated by comparing the first accumulated exhaust heat at the oxygen sensor installation position with the exhaust heat threshold, and determines whether condensed water will still form at the position by comparing the first wall temperature at the oxygen sensor installation position with the dew point temperature. When it is determined that the first accumulated exhaust heat is greater than the exhaust heat threshold, and the first wall temperature is greater than the dew point temperature, that is, it is determined that all condensed water at the oxygen sensor installation position has evaporated and no condensed water will be formed, the oxygen sensor is turned on. This can reduce the risk of the oxygen sensor being subjected to thermal shock from condensed water after being turned on, and enable the oxygen sensor to work normally.

[0036] The present invention controls the opening of the oxygen sensor by comprehensively considering the evaporation of condensed water at the installation position of the oxygen sensor and the formation of condensed water, which is more comprehensive and can more effectively reduce the risk of damage to the oxygen sensor after it is opened.

[0037] In one embodiment, the exhaust pipe further includes a catalyst; S101 may specifically include: determining a first cumulative exhaust heat at the oxygen sensor installation position by the following formula: ; in, is the first accumulated exhaust heat at the oxygen sensor installation position at the current moment; The second accumulated exhaust heat at the oxygen sensor installation position at the previous moment; It is the change in exhaust heat at the oxygen sensor installation location at the current moment.

[0038] When the engine is started for the first time in each driving cycle, the accumulated exhaust heat is set to 0; when the engine is started, the high-temperature exhaust flow transfers heat to the oxygen sensor installation location, and the accumulated exhaust heat at the oxygen sensor installation location continues to increase; after the engine is stopped, there is no exhaust to provide heat, and the heat exchange with the external environment causes the accumulated exhaust heat at the oxygen sensor installation location to continue to decrease. Therefore, it is necessary to calculate based on the start / stop state of the engine. .

[0039] When the engine is stopped, ,in, is the first wall temperature at the oxygen sensor installation position at the current moment; is the second wall temperature at the oxygen sensor installation position at the previous moment; is the heat coefficient corresponding to the temperature change.

[0040] When the engine is running, ,in, is the first exhaust gas mass flow in the exhaust pipe at the current moment; is the exhaust temperature in the exhaust pipe at the current moment; Indicates the exhaust temperature threshold that brings heat to the oxygen sensor installation location; is the exhaust gas specific heat capacity; It is the factor that affects the change in exhaust heat when the catalyst is running.

[0041] In one embodiment, the exhaust heat threshold is approximately proportional to the amount of heat required to transfer the exhaust heat to the exhaust pipe wall after the engine is started so that there is no condensed water at the oxygen sensor installation location. The exhaust heat threshold can be calculated based on the wall temperature at the sensor installation location when the engine is started, the engine cooling water temperature, and the number of repeated starts. Specifically, the exhaust heat threshold The calculation formula is:

[0042] in, is the original exhaust heat threshold, It is the influence factor of the number of repeated starts of the engine within a preset time period on the exhaust heat threshold.

[0043] The original exhaust heat threshold can be calculated by checking the first wall temperature at the oxygen sensor installation position and the engine cooling water temperature when the engine is cold started, and the size of the original exhaust heat threshold decreases as the first wall temperature at the oxygen sensor installation position and the engine cooling water temperature increase.

[0044] If the dew point is not reached in the previous driving cycle, the condensed water in the exhaust system is not completely evaporated, and more condensed water is expected to exist at the next start, requiring more accumulated exhaust heat. Therefore, the original exhaust heat threshold needs to be corrected according to the engine restart counter. ① If the dew point end point is not reached when the engine is powered off, the restart counter is +1; ② When the dew point end point is reached when the engine is powered off, the restart counter is set to 0; ③ The original exhaust heat threshold is corrected according to the restart counter value. The larger the restart counter value, the more accumulated exhaust heat is required, and the greater the heat correction to the original exhaust heat threshold.

[0045] Reference Figure 3 , shows a flow chart of another embodiment of the oxygen sensor control method provided by the present invention, the method comprising: S201, obtaining a first accumulated exhaust heat amount and a first wall temperature at a location where the oxygen sensor is installed.

[0046] S202: Determine whether the first accumulated exhaust heat is greater than an exhaust heat threshold, and whether the first wall temperature is greater than a dew point temperature.

[0047] S203: If the first accumulated exhaust heat is greater than the exhaust heat threshold and the first wall temperature is greater than the dew point temperature, the oxygen sensor is turned on.

[0048] S204, after the oxygen sensor is turned on, the engine stall information is determined in real time.

[0049] Stalling refers to a situation where the engine suddenly stops running during operation. Stalling usually occurs in the following situations: ① Improper throttle control: The driver suddenly releases the accelerator or steps on the brake during driving, causing the engine to lose sufficient air intake and fuel supply and stop running. ② Engine failure: Mechanical failure inside the engine (such as spark plug failure, fuel pump failure, etc.) may cause the engine to fail to operate normally and eventually stall. ③ Improper clutch operation: In a manual transmission vehicle, if the driver does not operate the clutch correctly when shifting gears, it may cause the engine to stall. ④ Air flow sensor failure: A failure in the air flow sensor may cause the engine control system to be unable to correctly adjust the mixture ratio of fuel and air, resulting in a stall.

[0050] When the engine is in a stall, the wall temperature at the oxygen sensor installation location may be lower than the dew point temperature again. At this time, condensed water will re-form at the oxygen sensor installation location. Therefore, after the dew point state passes and the oxygen sensor is turned on, the engine stall information needs to be detected in real time. The stall information may include stall time, stall degree, etc. The stall degree can be judged by the engine fuel consumption and engine speed.

[0051] S205: Determine whether the stall information meets a preset condition.

[0052] S206, if the stall information meets the preset conditions, the oxygen sensor is turned off, and the process returns to the step of obtaining the accumulated exhaust heat and the wall temperature at the oxygen sensor installation position.

[0053] If the stall time is too long and / or the stall degree is too large, the dew point state may be set to dew point failure, and the oxygen sensor may be turned off, and then the process returns to S101 to determine whether the oxygen sensor meets the start-up condition.

[0054] This embodiment monitors the stall information of the engine after the oxygen sensor is turned on to determine whether condensed water will be re-formed at the oxygen sensor installation position after the oxygen sensor is turned on. If it is determined that condensed water will be re-formed, the oxygen sensor is turned off to avoid damage to the oxygen sensor due to thermal shock of the condensed water.

[0055] In one embodiment, the stall information of the engine includes: a supply relationship characterization value, the supply relationship characterization value is the ratio of the combustion heat of the engine and the corresponding coefficient of the second exhaust mass flow in the exhaust pipe; then S205 may specifically include: judging whether the supply relationship characterization value is less than a preset characterization threshold; S206 may specifically include: if the supply relationship characterization value is less than the preset characterization threshold, turning off the oxygen sensor, and returning to the step of obtaining the accumulated exhaust heat and wall temperature at the oxygen sensor installation position.

[0056] When the fuel consumption is low, the corresponding heat supply is smaller, and when the engine speed is high, the corresponding mass flow is larger. The exhaust heat input to the oxygen sensor installation position is low and the exhaust mass flow is large, indicating that the engine is in a stall at this time. Therefore, the supply relationship characterization value of the engine's combustion heat and the second exhaust mass flow in the exhaust pipe can be determined by the engine fuel consumption and the engine speed. The supply relationship characterization value is used to characterize the relative size relationship between the engine's combustion heat and the second exhaust mass flow in the exhaust pipe.

[0057] Specifically, the signal fac1 can be obtained by checking the MAP according to the fuel consumption, and fac1 increases as the fuel consumption increases; the signal fac2 can be obtained by checking the MAP according to the engine speed, and fac2 increases as the engine speed increases. The ratio fac of fac1 and fac2 can be used as a representation value of the supply relationship between the combustion heat of the engine and the second exhaust mass flow in the exhaust pipe.

[0058] The preset characterization threshold is related to the ambient temperature. The lower the ambient temperature, the larger the corresponding preset characterization threshold. Therefore, the preset characterization threshold can be determined according to the ambient temperature.

[0059] In one embodiment, the oxygen sensor control method further includes: after turning on the oxygen sensor, obtaining in real time the third wall temperature at the oxygen sensor installation position; judging whether the third wall temperature is less than the dew point temperature; if the third wall temperature is less than the dew point temperature, turning off the oxygen sensor and returning to S101.

[0060] When the engine is in a stall, the wall temperature at the oxygen sensor installation location may be lower than the dew point temperature again. At this time, condensed water will re-form. Therefore, after the oxygen sensor is turned on, it is necessary to detect the third wall temperature at the oxygen sensor installation location in real time. When the third wall temperature is lower than the dew point temperature, the oxygen sensor is turned off.

[0061] Reference Figure 4 , showing a schematic diagram of the dew point state control flow of an oxygen sensor provided by the present invention. First, the dew point of the wide-range oxygen sensor is judged to pass, specifically: judge whether the first cumulative exhaust heat is greater than the exhaust heat threshold, and whether the first wall temperature is greater than the dew point temperature; if the first cumulative exhaust heat is greater than the exhaust heat threshold, and the first wall temperature is greater than the dew point temperature, then set the dew point state of the wide-range oxygen sensor to dew point pass, and turn on the wide-range oxygen sensor at this time; then perform the dew point reset judgment of the wide-range oxygen sensor, specifically: after turning on the wide-range oxygen sensor, judge whether the supply relationship characterization value is less than the preset characterization threshold, and whether the third wall temperature at the installation position of the wide-range oxygen sensor is less than the dew point temperature; if the supply relationship characterization value is less than the preset characterization threshold, or the third wall temperature at the installation position of the wide-range oxygen sensor is less than the dew point temperature, then set the dew point state of the wide-range oxygen sensor to dew point not pass, and turn off the wide-range oxygen sensor at this time, and return to the step of judging the dew point of the wide-range oxygen sensor.

[0062] In one embodiment, the present invention further provides a controller for executing the steps in any one of the above oxygen sensor control methods. The controller may be an ECU.

[0063] In one embodiment, the present invention also provides a vehicle, comprising an oxygen sensor, an engine, an exhaust pipe and the above-mentioned controller; wherein the oxygen sensor is installed on the exhaust pipe of the engine, and the controller is used to perform the steps in any one of the above-mentioned oxygen sensor control methods.

[0064] In one embodiment, the present invention further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of any one of the above-mentioned oxygen sensor control methods are implemented.

[0065] Those skilled in the art will appreciate that all or part of the processes of the above-mentioned embodiments can be implemented by instructing related hardware through a computer program, and the program can be stored in a computer-readable storage medium, wherein the computer-readable storage medium is a disk, an optical disk, a read-only storage memory, or a random access memory, etc.

[0066] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. An oxygen sensor control method, characterized in that: The oxygen sensor is installed on the exhaust pipe of the engine, and the method comprises: Acquire a first accumulated exhaust heat and a first wall temperature at the oxygen sensor installation position; determining whether the first accumulated exhaust heat is greater than an exhaust heat threshold, and whether the first wall temperature is greater than a dew point temperature; If the first accumulated exhaust heat is greater than the exhaust heat threshold and the first wall temperature is greater than the dew point temperature, the oxygen sensor is turned on.

2. The oxygen sensor control method according to claim 1, characterized in that: The exhaust pipe also includes a catalyst; the step of obtaining a first accumulated exhaust heat at the oxygen sensor installation position includes: The first accumulated exhaust heat at the oxygen sensor installation position is determined by the following formula: ; in, is the first accumulated exhaust heat at the oxygen sensor installation position at the current moment; is the second accumulated exhaust heat at the oxygen sensor installation position at the last moment; is the change in exhaust heat at the oxygen sensor installation position at the current moment; When the engine is in a stopped state, ,in, is the first wall temperature at the oxygen sensor installation position at the current moment; is the second wall temperature at the oxygen sensor installation position at the last moment; is the heat coefficient corresponding to the temperature change; When the engine is in operation, ,in, is the first exhaust gas mass flow in the exhaust pipe at the current moment; is the exhaust gas temperature in the exhaust pipe at the current moment; represents an exhaust temperature threshold value that brings heat to the installation position of the oxygen sensor; is the exhaust gas specific heat capacity; is an influencing factor on the change in the exhaust heat when the catalyst is running.

3. The oxygen sensor control method according to claim 1, characterized in that: The exhaust heat threshold is determined according to a third wall temperature at the oxygen sensor installation position when the engine is started, an engine cooling water temperature, and a number of repeated engine starts.

4. The oxygen sensor control method according to claim 1, characterized in that: The method further comprises: When the oxygen sensor is turned on, the stall information of the engine is determined in real time; Determining whether the stall information meets a preset condition; If the stall information satisfies the preset condition, the oxygen sensor is turned off, and the process returns to the step of obtaining the accumulated exhaust heat and the wall temperature at the oxygen sensor installation position.

5. The oxygen sensor control method according to claim 4, characterized in that: The stall information of the engine includes: a supply relationship characterization value, wherein the supply relationship characterization value is a ratio of the combustion heat of the engine to a corresponding coefficient of the second exhaust mass flow in the exhaust pipe; and the determining whether the stall information satisfies a preset condition includes: Determining whether the supply relationship characterization value is less than a preset characterization threshold; If the stall information satisfies a preset condition, the oxygen sensor is turned off, and the step of returning to obtain the cumulative exhaust heat and the wall temperature at the oxygen sensor installation position includes: If the supply relationship characterization value is less than the preset characterization threshold, the oxygen sensor is turned off, and the process returns to the step of obtaining the accumulated exhaust heat and the wall temperature at the oxygen sensor installation position.

6. The oxygen sensor control method according to claim 5, characterized in that: The preset characterization threshold is determined according to the ambient temperature.

7. The oxygen sensor control method according to claim 1, characterized in that: The method further comprises: When the oxygen sensor is turned on, the third wall temperature at the oxygen sensor installation position is obtained in real time; determining whether the third wall temperature is less than the dew point temperature; If the third wall temperature is lower than the dew point temperature, the oxygen sensor is turned off, and the process returns to the step of obtaining the cumulative exhaust heat and the wall temperature at the oxygen sensor installation position.

8. A controller, characterized in that: Used to execute the steps of the oxygen sensor control method as described in any one of claims 1 to 7.

9. A vehicle, characterized in that: The vehicle comprises an oxygen sensor, an engine, an exhaust pipe and the controller as claimed in claim 8; wherein the oxygen sensor is mounted on the exhaust pipe of the engine.

10. A computer-readable storage medium, characterized in that: Used to store a computer-readable program, wherein when the program or instruction is executed by a processor, the steps of the oxygen sensor control method according to any one of claims 1 to 7 can be implemented.

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