Method and device for predicting engine oil life

Abstract

The present application relates to the field of vehicle technology, and specifically to a method and device for predicting the life of engine oil, which is used to solve the problem that the existing technology cannot accurately predict the life of engine oil. The method determines the oxidation life of the engine oil based on the difference between each temperature value of the engine oil and the set temperature value and the proportion of the time when each temperature value of the engine oil is maintained during the actual operation time of the engine; determines the acid capacity life of the engine oil based on the rate of oil deterioration caused by the increase of acidic substances in the engine oil under various working conditions of the engine and the proportion of the time when each working condition of the engine is running during the actual operation time of the engine; determines whether the engine oil needs to be replaced based on the oxidation life of the engine oil, the acid capacity life of the engine oil and the carbon capacity life of the engine oil, wherein the carbon capacity life of the engine oil represents the carbon capacity life value of the engine oil after the carbon content in the oil increases and the limit value of the carbon capacity life of the engine oil decreases during the actual operation time of the engine. The present application can accurately predict the life of the engine oil and avoid replacing the engine oil too early or too late.

Description

Technical Field

[0001] The present application belongs to the field of vehicle technology, and in particular relates to a method and device for predicting engine oil life. Background Art

[0002] Engine oil protects the engine from wear and tear. Oil performance deteriorates over time, so timely oil changes are essential to ensure proper engine operation. Oil life is affected by a variety of factors, including engine operating conditions, oil quality, the engine operating environment, and combustion products in crankcase blowby. These factors can affect oil life and cause oil performance to deteriorate over time. Crankcase blowby refers to the leakage of some of the combustible mixture and combustion products (including acidic substances and soot) from the cylinder into the crankcase via the piston rings during engine operation. Soot increases the carbon content in the oil, which in turn increases oil viscosity and shortens oil life. The increase in acidic substances also reduces oil performance, shortening oil life. Therefore, accurate prediction of oil life is crucial to determine the optimal oil change schedule. Changing the oil too early wastes resources, while changing it too late can damage the engine and affect its proper operation.

[0003] In the existing technology, oil life prediction is mostly based on pre-setting mileage thresholds or oil change time periods based on empirical values, or only considering the impact of soot on oil life. Such prediction methods lack in-depth analysis of the oil failure mechanism and cannot accurately predict the actual life of the oil, especially when the performance of the oil changes more complexly under different operating conditions. Summary of the Invention

[0004] In response to the above problems, the present application provides an engine oil life prediction method and device, which can accurately predict the life of the engine oil and avoid changing the oil too early or too late.

[0005] In a first aspect, the present application provides a method for predicting engine oil life, the method comprising:

[0006] Determine the oil oxidation life based on the difference between each oil temperature value and the set temperature value and the proportion of the time the oil temperature value is maintained during the actual engine operation time; wherein the actual engine operation time is the actual engine operation time during the current engine oil change cycle;

[0007] Determining the oil acid capacity life based on the rate of oil deterioration due to the increase of acidic substances in the oil under various engine operating conditions and the proportion of the engine operating time under various operating conditions within the actual engine operating time;

[0008] Based on the oil oxidation life, the oil acid capacity life and the oil carbon capacity life, it is determined whether the oil needs to be replaced, wherein the oil carbon capacity life represents the oil carbon capacity life value after the oil carbon capacity life limit value decreases as the carbon content in the oil increases during the actual engine operation time.

[0009] In one possible implementation, determining the oil oxidation life based on the difference between each oil temperature value and a set temperature value and the ratio of the time the oil temperature value is maintained during the actual engine operation time includes:

[0010] Determining the single-point oxidation life of the engine oil at each temperature value of the engine oil based on the difference between each temperature value of the engine oil and the set temperature value and the initial oxidation life of the engine oil at the set temperature;

[0011] The oil oxidation life is determined based on the single-point oil oxidation life of each temperature value of the oil and the ratio of the time when each temperature value of the oil is maintained during the actual operation time of the engine.

[0012] In a possible implementation, the single-point oil oxidation life at each temperature value of the oil satisfies the following formula:

[0013]

[0014] Wherein, Ai is the single-point oil oxidation life of the oil at the i-th temperature value; a is the initial oxidation life of the oil at the set temperature; and t is the difference between the i-th temperature value of the oil and the set temperature value.

[0015] In one possible implementation, the engine oil oxidation life satisfies the following formula:

[0016]

[0017] Wherein, A is the oil oxidation life; Ai is the single-point oil oxidation life of the oil at the i-th temperature value, and the oil has m temperature values ​​during the actual operation time of the engine; Qi is the proportion of the maintenance time of the oil at the i-th temperature value during the actual operation time of the engine.

[0018] In one possible implementation, determining the oil acid capacity life based on the rate of oil deterioration due to an increase in acidic substances in the oil under various engine operating conditions and the proportion of the engine operating time under various operating conditions within the actual engine operating time includes:

[0019] Determining the oil acid failure slope for each engine operating condition during the actual engine operation time based on the corresponding relationship between each engine operating condition and the oil acid failure slope; wherein the oil acid failure slope is used to characterize the rate of oil deterioration due to an increase in acidic substances in the oil under each engine operating condition;

[0020] Determining the single-point oil acid capacity life of each operating condition of the engine based on the oil acid capacity life limit value and the oil acid capacity failure slope of each operating condition of the engine during the actual operation time of the engine;

[0021] The oil acid capacity life is determined based on the single-point oil acid capacity life of each operating condition of the engine and the proportion of the engine operating time of each operating condition during the actual operating time of the engine.

[0022] In a possible implementation, the correspondence between various operating conditions of the engine and the oil acid failure slope is obtained based on the combustion temperature and fuel consumption of the engine under different operating conditions.

[0023] In a possible implementation, the single-point oil acid capacity life of the engine under various operating conditions satisfies the following formula:

[0024] Bj=b / Xj

[0025] Among them, Bj is the single-point oil acid capacity life of the engine in the jth operating condition; b is the oil acid capacity life limit value; Xj is the oil acid capacity failure slope of the engine in the jth operating condition.

[0026] In a possible implementation, the engine oil acid capacity life satisfies the following formula:

[0027]

[0028] Among them, B is the oil acid capacity life; Bj is the single-point oil acid capacity life of the engine in the jth operating condition, and the engine has n operating conditions during the actual operating time of the engine; Pj is the proportion of the operating time of the engine in the jth operating condition during the actual operating time of the engine.

[0029] In one possible implementation, determining whether the engine oil needs to be replaced based on the engine oil oxidation life, the engine oil acid capacity life, the engine oil carbon capacity life, and the actual engine operating time includes:

[0030] Selecting the minimum value among the engine oil oxidation life, the engine oil acid capacity life, and the engine oil carbon capacity life as the engine oil life value;

[0031] Determine whether the actual engine operating time exceeds the engine oil life value, if so, the engine oil needs to be replaced, if not, the engine oil does not need to be replaced; or

[0032] Determine whether the vehicle's mileage since the last oil change exceeds a predicted mileage; if so, the oil needs to be changed; if not, the oil does not need to be changed, wherein the predicted mileage is determined based on the average vehicle speed during the actual operating time of the engine and the oil life value.

[0033] In a second aspect, the present application provides an engine oil life prediction device, the device comprising:

[0034] A first life prediction module is configured to determine the oxidation life of the engine oil based on the difference between each temperature value of the engine oil and the set temperature value and the proportion of the time the oil temperature is maintained at each temperature value during the actual engine operation time; wherein the actual engine operation time is the actual engine operation time during the current engine oil change cycle;

[0035] A second life prediction module is used to determine the oil acid capacity life according to the rate of oil deterioration caused by the increase of acidic substances in the oil under various operating conditions of the engine and the proportion of the engine operating time under various operating conditions within the actual operating time of the engine;

[0036] An engine oil replacement strategy module is used to determine whether the engine oil needs to be replaced based on the engine oil oxidation life, the engine oil acid capacity life, and the engine oil carbon capacity life, wherein the engine oil carbon capacity life represents the engine oil carbon capacity life value after the engine oil carbon capacity life limit value decreases with the increase of carbon content in the random oil during the actual operation time of the engine.

[0037] In a possible implementation manner, the first lifespan prediction module is specifically configured to:

[0038] Determining the single-point oxidation life of the engine oil at each temperature value of the engine oil based on the difference between each temperature value of the engine oil and the set temperature value and the initial oxidation life of the engine oil at the set temperature;

[0039] The oil oxidation life is determined based on the single-point oil oxidation life of each temperature value of the oil and the ratio of the time when each temperature value of the oil is maintained during the actual operation time of the engine.

[0040] In one possible implementation, the single-point oil oxidation life at each temperature value of the oil satisfies the following formula:

[0041]

[0042] Wherein, Ai is the single-point oil oxidation life of the oil at the i-th temperature value; a is the initial oxidation life of the oil at the set temperature; and t is the difference between the i-th temperature value of the oil and the set temperature value.

[0043] In one possible implementation, the engine oil oxidation life satisfies the following formula:

[0044]

[0045] Wherein, A is the oil oxidation life; Ai is the single-point oil oxidation life of the oil at the i-th temperature value, and the oil has m temperature values ​​during the actual operation time of the engine; Qi is the proportion of the maintenance time of the oil at the i-th temperature value during the actual operation time of the engine.

[0046] In a possible implementation manner, the second lifespan prediction module is specifically configured to:

[0047] Determining the oil acid failure slope for each engine operating condition during the actual engine operation time based on the corresponding relationship between each engine operating condition and the oil acid failure slope; wherein the oil acid failure slope is used to characterize the rate of oil deterioration due to an increase in acidic substances in the oil under each engine operating condition;

[0048] Determining the single-point oil acid capacity life of each operating condition of the engine based on the oil acid capacity life limit value and the oil acid capacity failure slope of each operating condition of the engine during the actual operation time of the engine;

[0049] The oil acid capacity life is determined based on the single-point oil acid capacity life of each operating condition of the engine and the proportion of the engine operating time of each operating condition during the actual operating time of the engine.

[0050] In a possible implementation, the correspondence between various operating conditions of the engine and the oil acid failure slope is obtained based on the combustion temperature and fuel consumption of the engine under different operating conditions.

[0051] In a possible implementation, the single-point oil acid capacity life of the engine under various operating conditions satisfies the following formula:

[0052] Bj=b / Xj

[0053] Among them, Bj is the single-point oil acid capacity life of the engine in the jth operating condition; b is the oil acid capacity life limit value; Xj is the oil acid capacity failure slope of the engine in the jth operating condition.

[0054] In a possible implementation, the engine oil acid capacity life satisfies the following formula:

[0055]

[0056] Among them, B is the oil acid capacity life; Bj is the single-point oil acid capacity life of the engine in the jth operating condition, and the engine has n operating conditions during the actual operating time of the engine; Pj is the proportion of the operating time of the engine in the jth operating condition during the actual operating time of the engine.

[0057] In one possible implementation, the oil replacement strategy module is specifically configured to:

[0058] Selecting the minimum value among the engine oil oxidation life, the engine oil acid capacity life, and the engine oil carbon capacity life as the engine oil life value;

[0059] Determine whether the actual engine operating time exceeds the engine oil life value, if so, the engine oil needs to be replaced, if not, the engine oil does not need to be replaced; or

[0060] Determine whether the vehicle's mileage since the last oil change exceeds a predicted mileage; if so, the oil needs to be changed; if not, the oil does not need to be changed, wherein the predicted mileage is determined based on the average vehicle speed during the actual operating time of the engine and the oil life value.

[0061] The beneficial effects of this application are as follows:

[0062] The present application provides a method and device for predicting the oil life of an engine. The method comprehensively considers the oxidation of the oil at different temperatures and the deterioration of the oil due to the increase of acidic substances and the increase of carbon content under different operating conditions of the engine, quantifies the three key parameters of the oil oxidation life, the oil acid capacity life and the oil carbon capacity life, and combines the actual operating time and operating condition distribution information of the engine to achieve a more scientific and reasonable prediction of the oil life. The present application not only helps to reduce unnecessary oil changes, but also reduces the risk of engine failure caused by oil deterioration, thereby improving the reliability and service life of the engine. Moreover, the prediction method of the present application will not be significantly adjusted and revised due to changes in engine models or changes in performance calibration data, and can provide reliable oil life prediction results in a variety of situations.

[0063] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The purposes and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. Obviously, the drawings introduced below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0065] Figure 1 A schematic flow chart of a method for predicting engine oil life provided in an embodiment of the present application;

[0066] Figure 2 A schematic diagram of an engine oil life prediction device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0067] In order to make the purpose, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application. Unless there is a conflict, the embodiments in the present application and the features in the embodiments can be combined with each other in any way. In addition, although a logical order is shown in the flowchart, in some cases, the steps shown or described can be performed in an order different from that here.

[0068] The terms "first" and "second" in the specification and claims of this application and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive protection. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally also includes steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices. "Multiple" in this application can mean at least two, for example, two, three or more, and the embodiments of this application are not limited thereto.

[0069] The following description of exemplary embodiments of the present application is made in conjunction with the accompanying drawings, which include various details of the embodiments of the present application to facilitate understanding, and they should be considered as merely exemplary. Therefore, those of ordinary skill in the art should recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope disclosed in this application. Similarly, for the sake of clarity and conciseness, the description of well-known functions and structures is omitted in the following description. It should be noted that in the embodiments of the present application, certain software, components, models and other existing solutions in the industry may be mentioned, which should be considered as exemplary, and their purpose is only to illustrate the feasibility of the implementation of the technical solution of the present application, but it does not mean that the applicant has or will necessarily use the solution.

[0070] Before introducing the engine oil life prediction method provided by the embodiment of the present application, in order to facilitate understanding, the technical background of the embodiment of the present application is first introduced in detail below.

[0071] Engine oil protects the engine from wear and tear. Oil performance deteriorates over time, so timely oil changes are essential to ensure proper engine operation. Oil life is affected by a variety of factors, including engine operating conditions, oil quality, the engine operating environment, and combustion products in crankcase blowby. These factors can affect oil life and cause oil performance to deteriorate over time. Crankcase blowby refers to the leakage of some of the combustible mixture and combustion products (including acidic substances and soot) from the cylinder into the crankcase via the piston rings during engine operation. Soot increases the carbon content in the oil, which in turn increases oil viscosity and shortens oil life. The increase in acidic substances also reduces oil performance, shortening oil life. Therefore, accurate prediction of oil life is crucial to determine the optimal oil change schedule. Changing the oil too early wastes resources, while changing it too late can damage the engine and affect its proper operation.

[0072] In the existing technology, oil life prediction is mostly based on pre-setting mileage thresholds or oil change time periods based on empirical values, or only considering the impact of soot on oil life. Such prediction methods lack in-depth analysis of the oil failure mechanism and cannot accurately predict the actual life of the oil, especially when the performance of the oil changes more complexly under different operating conditions.

[0073] In view of this, in order to accurately predict the life of engine oil and avoid premature or late oil replacement, the embodiments of the present application provide an engine oil life prediction method and device. The following describes some preferred embodiments of the present application in conjunction with the accompanying drawings.

[0074] Example 1:

[0075] Figure 1 A flow chart of a method for predicting engine oil life is provided in some embodiments of the present application, such as Figure 1 As shown, the process includes the following steps:

[0076] S101: Determine the oxidation life of the engine oil based on the difference between each temperature value of the engine oil and the set temperature value and the proportion of the time when each temperature value of the engine oil is maintained during the actual engine operation time.

[0077] The actual engine running time is the actual engine running time during the oil change cycle of this engine.

[0078] In the embodiment of the present application, each oil change cycle starts from the last oil change or from the first time the engine is used. Correspondingly, if the current oil change cycle starts from the last oil change, the actual engine running time is from the last oil change to the current moment; if the current oil change cycle starts from the first time the engine is used, the actual engine running time is from the first time the engine is used to the current moment.

[0079] Optionally, the oil life prediction method of the present application is executed at set intervals during each oil change cycle until it is determined that the oil needs to be changed during the current oil change cycle.

[0080] In the embodiment of the present application, the various temperature values ​​of the engine oil are different temperature values ​​of the engine oil detected during the actual operation time of the engine. Specifically, they can be the temperature values ​​of the engine oil obtained by a temperature sensor.

[0081] The set temperature value is the reference benchmark defined in this application, and the set temperature value can be set according to the recommended operating temperature range provided by the engine oil manufacturer. For example, the set temperature value can be the ideal operating temperature value of the engine under standard operating conditions. At the set temperature, the length of time required for the engine oil newly added to the engine from the beginning of use until its oxidation degree reaches a predetermined unacceptable level is the initial oxidation life of the engine oil at the set temperature. It can be understood that the oxidation rate of engine oil is different at different temperatures. The higher the temperature, the faster the oxidation reaction of the engine oil occurs, resulting in a faster reduction in the life of the engine oil. Therefore, this application can estimate the oxidation rate of the engine oil at various temperature values ​​of the engine oil by detecting the engine oil temperature during the actual operating time of the engine and comparing it with the set temperature value.

[0082] At the same time, this application takes into account the fact that engine oil oxidizes at different temperatures at different rates. The longer the oil is maintained at a certain temperature, the more severe the oxidation caused by the temperature. Therefore, it is important to consider not only the temperature value itself but also the duration of the temperature.

[0083] Therefore, when determining the oil oxidation life, this application also considers the proportion of time the oil maintains each temperature value during the actual engine operating time. By combining these two factors—the temperature difference between the actual oil temperature and the set temperature value, and the time the various temperature values ​​are maintained—to determine the oil oxidation life, not only does it consider the effect of temperature on oil oxidation, but also the cumulative effect of this effect over time. This allows the application to more accurately estimate the life lost to oil oxidation during the actual engine operating time, thereby improving the accuracy of oil life prediction.

[0084] As a feasible implementation, the specific steps of determining the oxidation life of the engine oil based on the difference between each temperature value of the engine oil and the set temperature value and the proportion of the time that each temperature value of the engine oil is maintained during the actual operation time of the engine include the following S101a-S101b:

[0085] S101a, determining the single-point oxidation life of the engine oil at each temperature value of the engine oil based on the difference between each temperature value of the engine oil and the set temperature value and the initial oxidation life of the engine oil at the set temperature;

[0086] Specifically, the following formula is used to determine the single-point oil oxidation life at various oil temperature values:

[0087]

[0088] Wherein, Ai is the single-point oil oxidation life of the oil at the i-th temperature value; a is the initial oxidation life of the oil at the set temperature; and t is the difference between the i-th temperature value of the oil and the set temperature value.

[0089] It should be noted that in the embodiments of this application, "single-point oil life" refers to the oil life under specific conditions. For example, when the condition is a certain temperature of the oil, "single-point oil oxidation life" refers to the expected oxidation life of the oil at that specific temperature, i.e., the estimated time the oil will function normally as the oil's oxidizing substances increase at that specific temperature. For another example, when the condition is a certain engine operating condition, "single-point oil acid capacity life" refers to the expected acid capacity life of the oil under that operating condition, i.e., the estimated time the oil will function normally as the oil's acidic substances increase under that operating condition.

[0090] S101b: Determine the oil oxidation life based on the single-point oil oxidation life at each temperature value of the oil and the ratio of the time the oil temperature is maintained at each temperature value during the actual engine operation time.

[0091]

[0092] Among them, A is the oil oxidation life; Ai is the single-point oil oxidation life of the oil at the i-th temperature value, and the oil has m temperature values ​​during the actual engine operation time; Qi is the proportion of the maintenance time of the oil at the i-th temperature value during the actual engine operation time.

[0093] It can be seen that Formula 2 first multiplies the proportion corresponding to each temperature value by the single-point oil oxidation life of the temperature value to obtain the contribution value of the temperature value to the oxidation life. The contribution values ​​of all temperature values ​​are added together to obtain the comprehensive oxidation life during the actual operating time of the entire engine, that is, the oil oxidation life.

[0094] In this embodiment, the various temperatures experienced by the oil during actual engine operation and the duration of their exposure are first recorded. These temperature values ​​are then substituted into Equation 1 to derive the single-point oil oxidation life for each temperature. Because oil oxidation rates vary at different temperatures, the duration of exposure at each temperature is also considered. By combining these temperature differences and exposure durations, a more accurate estimate of the oil life lost due to oxidation over the entire oil change cycle can be achieved, ultimately determining the oil oxidation life.

[0095] S102: Determine the acid capacity life of the engine oil based on a rate of engine oil degradation due to an increase in acidic substances in the engine oil under various engine operating conditions and a proportion of the engine operating time under various engine operating conditions within the actual engine operating time.

[0096] As a feasible implementation method, the specific steps of determining the acid capacity life of the engine oil according to the rate of engine oil deterioration caused by the increase of acidic substances in the engine oil under various operating conditions and the proportion of the engine operating time under various operating conditions during the actual operating time of the engine include the following S102a-S102c:

[0097] S102a, determining the oil acid failure slope for each engine operating condition during the actual engine operation time based on the corresponding relationship between each engine operating condition and the oil acid failure slope.

[0098] Among them, the oil acid capacity failure slope is used to characterize the rate of oil deterioration caused by the increase of acidic substances in the oil under various operating conditions of the engine. The correspondence between various operating conditions of the engine and the oil acid capacity failure slope is obtained based on the combustion temperature and fuel consumption of the engine under different operating conditions.

[0099] Specifically, engine combustion temperature and fuel consumption affect the acid content in crankcase blowby, which in turn affects the acid content in the engine oil, and thus the oil's acid capacity life. Because different engine operating conditions correspond to different engine combustion temperatures and fuel consumption, the rate of acid accumulation varies under different engine operating conditions, resulting in different oil acid capacity failure slopes under different engine operating conditions.

[0100] Optionally, the correspondence between the various engine operating conditions and the oil acid failure slope in this application can be stored in a "combustion temperature and fuel consumption-oil acid failure slope relationship diagram." This relationship diagram is obtained by summarizing and analyzing a large amount of test data, and the corresponding oil acid failure slope can be found in the diagram based on the combustion temperature and fuel consumption. Since the engine's operating conditions are different, the combustion temperature and fuel consumption are different, and therefore different oil acid failure slopes can be obtained under different engine operating conditions. The oil acid failure slope corresponding to a working condition can be used to estimate the acidification rate of the oil under that working condition.

[0101] S102b, determining the single-point engine oil acid capacity life of each engine operating condition according to the engine oil acid capacity life limit value and the engine oil acid capacity failure slope of each engine operating condition during the actual engine operation time.

[0102] Specifically, the following formula is used to determine the single-point oil acid capacity life of the engine under various operating conditions:

[0103] Bj=b / Xj Formula 3

[0104] Among them, Bj is the single-point oil acid capacity life of the engine in the jth operating condition; b is the oil acid capacity life limit value; Xj is the oil acid capacity failure slope of the engine in the jth operating condition.

[0105] It should be noted that the oil acid capacity limit b depends on the quality of the oil itself. The oil acid capacity limit b is divided by the oil acid failure slope for each engine operating condition to obtain the single-point oil acid capacity life under each engine operating condition.

[0106] S102c: Determine the oil acid capacity life according to the single-point oil acid capacity life of each engine operating condition and the proportion of the engine operating time of each operating condition within the actual engine operating time.

[0107] Specifically, the following formula is used to determine the oil acid capacity life:

[0108]

[0109] Among them, B is the oil acid life; Bj is the single-point oil acid life of the engine in the jth operating condition, and the engine has n operating conditions during the actual engine operation time; Pj is the proportion of the engine's operating time in the jth operating condition during the actual engine operation time.

[0110] It can be seen that Formula 4 first multiplies the proportion corresponding to each operating condition by the single-point oil acid capacity life of the operating condition to obtain the contribution value of the operating condition to the acid capacity life. The contribution values ​​of all operating conditions are added together to obtain the comprehensive acid capacity life during the actual operating time of the entire engine, that is, the oil acid capacity life.

[0111] In the embodiment of the present application, the various operating conditions that the engine oil experiences during the actual operation of the engine and the length of time they are maintained are first recorded. Next, the oil acid capacity life limit is compared with the oil acid capacity failure slope corresponding to these operating conditions to obtain the single-point oil acid capacity life of the engine oil. Since the acidification rate of the engine oil varies under different operating conditions, the length of time maintained under each operating condition is also considered. In this way, by combining the differences in the acidification rates of different operating conditions and the maintenance time of different operating conditions, the life lost by the engine oil due to acidification during the entire oil change cycle can be more accurately estimated, and the oil acid capacity life can be ultimately determined.

[0112] S103: Determine whether the engine oil needs to be replaced based on the engine oil oxidation life, the engine oil acid capacity life, and the engine oil carbon capacity life.

[0113] Among them, the oil carbon capacity life represents the oil carbon capacity life value after the oil carbon capacity life limit value decreases as the carbon content in the random oil increases during the actual engine operation time. The oil carbon capacity life limit value depends on the oil quality.

[0114] In an embodiment of the present application, the oil carbon capacity life is determined based on the oil carbon capacity failure slope, the oil carbon capacity life limit, and the proportion of each engine operating condition under various engine operating conditions. Specifically, determining the oil carbon capacity life based on the oil carbon capacity failure slope, the oil carbon capacity life limit, and the proportion of each engine operating condition under various engine operating conditions includes the following steps:

[0115] Determining the oil carbon capacity failure slope for each engine operating condition according to the corresponding relationship between each engine operating condition and the oil carbon capacity failure slope;

[0116] Determine the single-point oil carbon capacity life of each engine operating condition based on the oil carbon capacity life limit value and the oil carbon capacity failure slope of each engine operating condition;

[0117] The oil carbon capacity life is determined based on the single-point oil carbon capacity life of each operating condition of the engine and the proportion of the engine's operating time in each operating condition during the actual engine operating time.

[0118] The relationship between various engine operating conditions and the oil carbon content failure slope is determined based on combustion calibration data under these conditions. This data includes injection advance angle, injection end time, maximum injection end time, rail pressure, and injection duration. Because different combustion calibration data correspond to different engine operating conditions, the rate of carbon content increase varies under different engine operating conditions, resulting in different oil carbon content failure slopes under these conditions.

[0119] Optionally, the correspondence between various engine operating conditions and the oil carbon tolerance failure slope in this application can be stored in a "combustion calibration data-oil carbon tolerance failure slope relationship diagram." This relationship diagram is obtained by summarizing and analyzing a large amount of test data. The corresponding oil carbon tolerance failure slope can be found in the diagram based on the combustion calibration data. Because different engine operating conditions result in different combustion calibration data, different oil carbon tolerance failure slopes can be obtained for different engine operating conditions. The oil carbon tolerance failure slope corresponding to a certain operating condition can be used to estimate the rate of increase of the carbon content of the engine oil under that operating condition.

[0120] Use the following formula to determine the single-point oil carbon capacity life:

[0121] Cj=c / Yj Formula 5

[0122] Among them, Cj is the single-point oil carbon tolerance life of the engine in the jth operating condition; c is the oil carbon tolerance life limit value; Yj is the oil carbon tolerance failure slope of the engine in the jth operating condition.

[0123] Use the following formula to determine the oil carbon capacity life:

[0124]

[0125] Among them, C is the oil acid life; Cj is the single-point oil acid life of the engine's j-th operating condition, and the engine has n operating conditions during the actual engine operating time; Pj is the proportion of the maintenance time of the engine's j-th operating condition during the actual engine operating time.

[0126] As a feasible implementation, determining whether the engine oil needs to be replaced based on the engine oil oxidation life, the engine oil acid capacity life, the engine oil carbon capacity life, and the actual engine operating time includes the following steps S103a-S103c:

[0127] S103a, selecting the minimum value among the engine oil oxidation life, the engine oil acid capacity life, and the engine oil carbon capacity life as the engine oil life value;

[0128] S103b, determining whether the actual engine operating time exceeds the engine oil life value, if so, the engine oil needs to be replaced, if not, the engine oil does not need to be replaced; or

[0129] S103c, determining whether the vehicle's mileage since the last oil change exceeds the predicted mileage. If so, the oil needs to be changed; otherwise, the oil does not need to be changed. The predicted mileage is determined based on the average vehicle speed and the oil life value during the actual engine operation time.

[0130] Specifically, the predicted mileage is the product of the average vehicle speed during the actual engine operation time and the engine oil life value.

[0131] The engine oil life prediction method provided in the embodiment of the present application comprehensively considers the oxidation of the oil at different temperatures and the deterioration of the oil due to the increase of acidic substances and the increase of carbon content under different operating conditions of the engine, quantifies the three key parameters of the oil oxidation life, the oil acid capacity life and the oil carbon capacity life, and combines the actual operating time and operating condition distribution information of the engine to achieve a more scientific and reasonable prediction of the oil life. This application not only helps to reduce unnecessary oil changes, but also reduces the risk of engine failure caused by oil deterioration, thereby improving the reliability and service life of the engine. Moreover, the prediction method of the present application will not be significantly adjusted and revised due to changes in the model or performance calibration data, and can provide reliable oil life prediction results in a variety of situations.

[0132] Example 2:

[0133] Based on the same technical concept, on the basis of the above embodiments, in an embodiment of the present application, there is provided a method for predicting the oil life of the engine of the vehicle using the above embodiments.

[0134] Example 3:

[0135] Based on the same technical concept, on the basis of the above embodiments, in an embodiment of the present application, an engine oil life prediction device is provided. Figure 2 This is a schematic diagram of the structure of an engine oil life prediction device provided in an embodiment of the present application. Figure 2 As shown, the device includes:

[0136] The first life prediction module 201 is configured to determine the oxidation life of the engine oil based on the difference between each temperature value of the engine oil and the set temperature value and the proportion of the time the oil temperature is maintained at each temperature value during the actual engine operation time; wherein the actual engine operation time is the actual engine operation time during the current engine oil change cycle;

[0137] The second life prediction module 202 is configured to determine the oil acid capacity life according to the rate of oil degradation caused by the increase of acidic substances in the oil under various engine operating conditions and the proportion of the engine operating time under various operating conditions within the actual engine operating time;

[0138] The engine oil replacement strategy module 203 is used to determine whether the engine oil needs to be replaced based on the engine oil oxidation life, the engine oil acid capacity life, and the engine oil carbon capacity life, wherein the engine oil carbon capacity life represents the engine oil carbon capacity life value after the engine oil carbon capacity life limit value decreases as the carbon content in the random oil increases during the actual operation time of the engine.

[0139] In a possible implementation, the first lifespan prediction module 201 is specifically configured to:

[0140] Determining the single-point oxidation life of the engine oil at each temperature value of the engine oil based on the difference between each temperature value of the engine oil and the set temperature value and the initial oxidation life of the engine oil at the set temperature;

[0141] The oil oxidation life is determined based on the single-point oil oxidation life of each temperature value of the oil and the ratio of the time when each temperature value of the oil is maintained during the actual operation time of the engine.

[0142] In one possible implementation, the single-point oil oxidation life at each temperature value of the oil satisfies the following formula:

[0143]

[0144] Wherein, Ai is the single-point oil oxidation life of the oil at the i-th temperature value; a is the initial oxidation life of the oil at the set temperature; and t is the difference between the i-th temperature value of the oil and the set temperature value.

[0145] In one possible implementation, the engine oil oxidation life satisfies the following formula:

[0146]

[0147] Wherein, A is the oil oxidation life; Ai is the single-point oil oxidation life of the oil at the i-th temperature value, and the oil has m temperature values ​​during the actual operation time of the engine; Qi is the proportion of the maintenance time of the oil at the i-th temperature value during the actual operation time of the engine.

[0148] In a possible implementation, the second lifespan prediction module 202 is specifically configured to:

[0149] Determining the oil acid failure slope for each engine operating condition during the actual engine operation time based on the corresponding relationship between each engine operating condition and the oil acid failure slope; wherein the oil acid failure slope is used to characterize the rate of oil deterioration due to an increase in acidic substances in the oil under each engine operating condition;

[0150] Determining the single-point oil acid capacity life of each operating condition of the engine based on the oil acid capacity life limit value and the oil acid capacity failure slope of each operating condition of the engine during the actual operation time of the engine;

[0151] The oil acid capacity life is determined based on the single-point oil acid capacity life of each operating condition of the engine and the proportion of the engine operating time of each operating condition during the actual operating time of the engine.

[0152] In a possible implementation, the correspondence between various operating conditions of the engine and the oil acid failure slope is obtained based on the combustion temperature and fuel consumption of the engine under different operating conditions.

[0153] In a possible implementation, the single-point oil acid capacity life of the engine under various operating conditions satisfies the following formula:

[0154] Bj=b / Xj

[0155] Among them, Bj is the single-point oil acid capacity life of the engine in the jth operating condition; b is the oil acid capacity life limit value; Xj is the oil acid capacity failure slope of the engine in the jth operating condition.

[0156] In a possible implementation, the engine oil acid capacity life satisfies the following formula:

[0157]

[0158] Among them, B is the oil acid capacity life; Bj is the single-point oil acid capacity life of the engine in the jth operating condition, and the engine has n operating conditions during the actual operating time of the engine; Pj is the proportion of the operating time of the engine in the jth operating condition during the actual operating time of the engine.

[0159] In a possible implementation, the oil replacement strategy module 203 is specifically configured to:

[0160] Selecting the minimum value among the engine oil oxidation life, the engine oil acid capacity life, and the engine oil carbon capacity life as the engine oil life value;

[0161] Determine whether the actual engine operating time exceeds the engine oil life value, if so, the engine oil needs to be replaced, if not, the engine oil does not need to be replaced; or

[0162] Determine whether the vehicle's mileage since the last oil change exceeds a predicted mileage; if so, the oil needs to be changed; if not, the oil does not need to be changed, wherein the predicted mileage is determined based on the average vehicle speed during the actual operating time of the engine and the oil life value.

[0163] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described devices and modules can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0164] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the modules is merely a logical function division. In actual implementation, there may be other division methods, such as multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or modules, which can be electrical, mechanical or other forms.

[0165] The modules described as separate components may or may not be physically separate, and the components shown as modules may or may not be physical modules, that is, they may be located in one place or distributed across multiple network modules. Some or all of the modules may be selected to achieve the purpose of the present embodiment according to actual needs.

[0166] In addition, the functional modules in the various embodiments of the present application may be integrated into a single processing module, or each module may exist physically separately, or two or more modules may be integrated into a single module. The aforementioned integrated modules may be implemented in the form of hardware or in the form of software functional modules. If the integrated modules are implemented in the form of software functional modules and sold or used as independent products, they may be stored in a computer-readable storage medium.

[0167] In the above embodiments, all or part of the embodiments may be implemented by software, hardware, firmware, or any combination thereof. When implemented by software, all or part of the embodiments may be implemented in the form of a computer program product.

[0168] The above is a detailed introduction to the technical solution provided by the present application. Specific examples are used in the present application to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for those skilled in the art, according to the ideas of the present application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

[0169] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0170] Obviously, those skilled in the art may make various changes and modifications to this application without departing from the spirit and scope of this application. Thus, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalents, this application is intended to include these modifications and variations.

Claims

1. A method for predicting engine oil life, characterized in that: include: Determine the oil oxidation life based on the difference between each oil temperature value and the set temperature value and the proportion of the time the oil temperature value is maintained during the actual engine operation time; wherein the actual engine operation time is the actual engine operation time during the current engine oil change cycle; Determining the oil acid capacity life based on the rate of oil deterioration due to the increase of acidic substances in the oil under various engine operating conditions and the proportion of the engine operating time under various operating conditions within the actual engine operating time; Based on the oil oxidation life, the oil acid capacity life and the oil carbon capacity life, it is determined whether the oil needs to be replaced, wherein the oil carbon capacity life represents the oil carbon capacity life value after the oil carbon capacity life limit value decreases as the carbon content in the oil increases during the actual engine operation time.

2. The method according to claim 1, wherein Determining the oil oxidation life based on the difference between each temperature value of the oil and the set temperature value and the proportion of the time the each temperature value of the oil is maintained during the actual engine operation time includes: Determining the single-point oxidation life of the engine oil at each temperature value of the engine oil based on the difference between each temperature value of the engine oil and the set temperature value and the initial oxidation life of the engine oil at the set temperature; The oil oxidation life is determined based on the single-point oil oxidation life of each temperature value of the oil and the ratio of the time when each temperature value of the oil is maintained during the actual operation time of the engine.

3. The method according to claim 2, wherein The single-point oil oxidation life of the oil at each temperature value satisfies the following formula: Wherein, Ai is the single-point oil oxidation life of the oil at the i-th temperature value; a is the initial oxidation life of the oil at the set temperature; and t is the difference between the i-th temperature value of the oil and the set temperature value.

4. The method according to claim 2, wherein The oil oxidation life satisfies the following formula: Wherein, A is the oil oxidation life; Ai is the single-point oil oxidation life of the oil at the i-th temperature value, and the oil has m temperature values ​​during the actual operation time of the engine; Qi is the proportion of the maintenance time of the oil at the i-th temperature value during the actual operation time of the engine.

5. The method according to claim 1, wherein The determination of the oil acid capacity life according to the rate of oil deterioration caused by the increase of acidic substances in the oil under various engine operating conditions and the proportion of the engine operating time under various operating conditions within the actual engine operating time includes: Determining the oil acid failure slope for each engine operating condition during the actual engine operation time based on the corresponding relationship between each engine operating condition and the oil acid failure slope; wherein the oil acid failure slope is used to characterize the rate of oil deterioration due to an increase in acidic substances in the oil under each engine operating condition; Determining the single-point oil acid capacity life of each operating condition of the engine based on the oil acid capacity life limit value and the oil acid capacity failure slope of each operating condition of the engine during the actual operation time of the engine; The oil acid capacity life is determined based on the single-point oil acid capacity life of each operating condition of the engine and the proportion of the engine operating time of each operating condition during the actual operating time of the engine.

6. The method according to claim 5, wherein The corresponding relationship between each operating condition of the engine and the oil acid failure slope is obtained based on the combustion temperature and fuel consumption of the engine under different operating conditions.

7. The method according to claim 5, wherein The single-point oil acid capacity life of the engine under various operating conditions satisfies the following formula: Bj=b / Xj Among them, Bj is the single-point oil acid capacity life of the engine in the jth operating condition; b is the oil acid capacity life limit value; Xj is the oil acid capacity failure slope of the engine in the jth operating condition.

8. The method according to claim 5, wherein The oil acid capacity life satisfies the following formula: Among them, B is the oil acid capacity life; Bj is the single-point oil acid capacity life of the engine in the jth operating condition, and the engine has n operating conditions during the actual operating time of the engine; Pj is the proportion of the operating time of the engine in the jth operating condition during the actual operating time of the engine.

9. The method according to any one of claims 1 to 8, wherein: The determining whether the engine oil needs to be replaced based on the engine oil oxidation life, the engine oil acid capacity life, the engine oil carbon capacity life, and the actual engine operating time includes: Selecting the minimum value among the engine oil oxidation life, the engine oil acid capacity life, and the engine oil carbon capacity life as the engine oil life value; Determine whether the actual engine operating time exceeds the engine oil life value, if so, the engine oil needs to be replaced, if not, the engine oil does not need to be replaced; or Determine whether the vehicle's mileage since the last oil change exceeds a predicted mileage; if so, the oil needs to be changed; if not, the oil does not need to be changed, wherein the predicted mileage is determined based on the average vehicle speed during the actual operating time of the engine and the oil life value.

10. An engine oil life prediction device, characterized in that: include: A first life prediction module is configured to determine the oxidation life of the engine oil based on the difference between each temperature value of the engine oil and the set temperature value and the proportion of the time the oil temperature is maintained at each temperature value during the actual engine operation time; wherein the actual engine operation time is the actual engine operation time during the current engine oil change cycle; A second life prediction module is used to determine the oil acid capacity life according to the rate of oil deterioration caused by the increase of acidic substances in the oil under various operating conditions of the engine and the proportion of the engine operating time under various operating conditions within the actual operating time of the engine; An engine oil replacement strategy module is used to determine whether the engine oil needs to be replaced based on the engine oil oxidation life, the engine oil acid capacity life, and the engine oil carbon capacity life, wherein the engine oil carbon capacity life represents the engine oil carbon capacity life value after the engine oil carbon capacity life limit value decreases with the increase of carbon content in the random oil during the actual operation time of the engine.

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