A control strategy for engine protection based on oil monitoring

Abstract

The present invention discloses a control strategy for engine protection based on oil monitoring, which relates to engine control technology. Determine whether the engine is started successfully; if the engine is started successfully, collect the real-time pressure value of the oil, and process the real-time pressure value with a multi-threshold protection judgment method to ensure that the engine operates in a state of normal oil pressure value; if the engine is not started successfully, collect the oil level value in the oil pan, and determine whether the oil level value is less than the set oil level extreme value; if the oil level value is less than the oil level extreme value, prohibit the engine from starting; otherwise, allow the engine to start. The present invention realizes the differentiation of oil level and pressure abnormalities in different scenarios, and then protects the engine through graded reminders and protection measures.

Description

Technical Field

[0001] The present invention relates to engine control technology, and more particularly to a control strategy for implementing engine protection based on engine oil monitoring. Background Art

[0002] The lubrication function of the engine is mainly achieved by engine oil, and engine oil also undertakes part of the cooling function. When engine oil is not added or the engine oil leaks, the lubrication of the engine system will fail and the cooling capacity will decrease. Insufficient engine oil, low oil viscosity, oil filter blockage and other manifestations of reduced oil pressure will also lead to weakened lubrication and cooling functions of the engine system. These problems will eventually lead to poor friction and lubrication effects on the surfaces of various components inside the engine, aggravating the wear of various parts, and causing overheating of internal engine components, ultimately causing serious problems such as bearing ablation and cylinder scuffing, and even causing the engine to be scrapped.

[0003] At present, the industry mainly uses oil pressure sensors or induction plugs installed on the main oil channel to sense and detect the oil pressure during the operation of the engine after starting, and then sends the pressure information to the vehicle instrument, which determines whether to activate the "low oil pressure indicator light" to prompt the driver, and the driver takes the initiative to take measures. However, in actual use, due to the limitations of the driver's professional knowledge and understanding of the instrument signal, information deviation often occurs, causing the driver to turn a blind eye to or underestimate the abnormal oil problem, which ultimately causes serious damage to the engine or even scrapping. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a control strategy for engine protection based on oil monitoring in response to the deficiencies in the prior art, thereby achieving differentiation of abnormal oil levels and pressures in different scenarios, and further protecting the engine through graded reminders and protection measures.

[0005] The control strategy for engine protection based on oil monitoring described in the present invention determines whether the engine is started successfully;

[0006] If the engine is started successfully, the real-time oil pressure value is collected and processed by a multi-threshold protection judgment method to ensure that the engine runs at a normal oil pressure value;

[0007] If the engine is not started successfully, the oil level value in the oil pan is collected, and it is determined whether the oil level value is less than a set oil level limit;

[0008] If the engine oil level value is less than the engine oil level extreme value, the engine starting is prohibited; otherwise, the engine starting is allowed.

[0009] The multi-threshold protection judgment method is:

[0010] Determine whether the real-time pressure value is less than a first set limit value; if so, monitor the accelerator pedal opening, and when the accelerator pedal opening is the accelerator pedal opening in the idle state, issue an engine torque limit instruction to limit the maximum output torque of the engine to a set torque extreme value; and at the same time determine whether the real-time pressure value is less than a second set limit value;

[0011] If so, a shutdown command is issued, and the engine stops running according to the shutdown command.

[0012] The engine stops running according to the shutdown instruction, specifically,

[0013] When the ECU receives the shutdown command, it gradually reduces the engine speed to idle speed with the calibrated shutdown step length;

[0014] When the engine speed is reduced to the idle speed, the engine is operated at the idle speed for a set time and then the engine is stopped and flamed out.

[0015] The set time is 30s-120s.

[0016] When the real-time pressure value is greater than or equal to the first set limit value, the process returns to the step of determining whether the engine is started successfully.

[0017] When the real-time pressure value is greater than or equal to the second set limit value, the process returns to the step of determining whether the engine is started successfully.

[0018] When the real-time pressure value is less than a first set limit, a low oil pressure indicator light on the instrument panel is activated.

[0019] Beneficial Effects

[0020] The advantages of the present invention are: the ECU monitors the oil pressure in the main oil channel and the oil level in the oil pan, and judges whether the engine oil meets the normal operation of the engine according to the oil pressure value and the oil level value, thereby realizing differentiation when the oil level and pressure are abnormal in different scenarios, and then protecting the engine through graded reminders and protection measures, while also ensuring driving safety and driving experience, and avoiding the problem of engine damage due to abnormal oil in the engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the control strategy flow of the present invention. DETAILED DESCRIPTION

[0022] The present invention will be further described below in conjunction with the embodiments, but it does not constitute any limitation to the present invention. Any limited number of modifications made by anyone within the scope of the claims of the present invention are still within the scope of the claims of the present invention.

[0023] See also Figure 1 The control strategy for realizing engine protection based on oil monitoring of the present invention first determines whether the engine is started successfully. If the engine is started successfully, the ECU collects the real-time pressure value of the oil in the main oil channel.

[0024] Then determine whether the real-time pressure value is less than the first set limit. If so, monitor the accelerator pedal opening, and when the accelerator pedal opening is the accelerator pedal opening in the idle state, issue an engine torque limit command to limit the maximum output torque of the engine to the set torque extreme value. The advantage of doing this is to avoid the problem that the engine output suddenly changes to the idle state during the driver's acceleration, which affects the driver's judgment of the vehicle state, thereby ensuring driving safety. Moreover, when the oil pressure is insufficient, the limitation of the maximum output torque can avoid the problem of reduced lubrication capacity caused by insufficient internal oil when the engine is running at high speed, which plays a role in preventing the engine from being easily damaged and ensures the safety of engine operation.

[0025] When the real-time pressure value is less than the first set limit, in addition to limiting the output torque of the engine, the low oil pressure indicator light on the instrument panel is also activated to give the driver a corresponding prompt.

[0026] If the real-time pressure value is less than the first set limit, then it is determined whether the real-time pressure value is less than the second set limit. When the real-time pressure value is less than the second set limit, a shutdown command is issued to stop the engine.

[0027] Considering that vehicles have different driving environments in different regions, if the engine is directly and actively shut down, it is easy to bring hidden dangers to road safety in some sections, such as uphill sections or turning sections. Therefore, in this embodiment, the specific implementation method of shutting down the engine due to insufficient oil pressure is divided into two steps.

[0028] First, when the ECU receives the shutdown command, it controls the engine to gradually reduce the engine speed to idle speed at a calibrated shutdown step. This active speed reduction action can remind the driver of vehicle failure and ensure the stability of vehicle operation.

[0029] Secondly, when the engine speed drops to idle speed, the engine will run at idle speed for a set time and then shut down the engine to facilitate the driver to make emergency operations such as pulling over or turning on the hazard lights.

[0030] In addition, the set time is 30s-120s. The setting of this time is mainly to ensure that the driver has sufficient time to make emergency operations and ensure the safety of parking. As for the specific time setting, it can be judged according to the current road conditions of the vehicle. For example, when the vehicle is on a flat road, the driver can park quickly, so the set time can be 30s, which can ensure the safety of parking and protect the engine a lot. When the vehicle is on a slope section, especially an uphill section, the vehicle travels slowly and it takes a long time to ensure the safe stop of the vehicle, so the slope section can be 120s. The monitoring of the road slope can be collected through relevant sensors on the vehicle.

[0031] Considering that the oil may leak during the driving of the vehicle, when the real-time pressure value is greater than or equal to the first set limit, the process returns to the step of determining whether the engine is started successfully to continue to determine whether the oil pressure is normal, so as to avoid insufficient oil pressure due to oil leakage.

[0032] Considering that the oil pressure is related to the weather, for example, in a low temperature environment, the viscosity of the oil is high, and when the vehicle is started, the oil pressure in the main oil channel is likely to be insufficient. However, after the oil becomes hot after the vehicle is started for a certain period of time, its pressure will return to normal. Therefore, when the real-time pressure value is between the two set limits, return to the step of judging whether the engine has started successfully to continue judging the oil pressure. Avoid the problem of misjudgment due to weather factors.

[0033] If the engine fails to start, the ECU will collect the oil level value in the oil pan and determine whether the oil level value is less than the set oil level limit. If the oil level value is less than the oil level limit, the engine is prohibited from starting; otherwise, the engine is allowed to start.

[0034] The above is only a preferred embodiment of the present invention. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the structure of the present invention, which will not affect the effect of the implementation of the present invention and the practicality of the patent.

Claims

1. A control strategy for engine protection based on oil monitoring, characterized in that: Determine whether the engine is started successfully; If the engine is started successfully, the real-time oil pressure value is collected and processed by a multi-threshold protection judgment method to ensure that the engine runs at a normal oil pressure value; If the engine is not started successfully, the oil level value in the oil pan is collected, and it is determined whether the oil level value is less than a set oil level limit; If the engine oil level value is less than the engine oil level extreme value, the engine is prohibited from starting; otherwise, the engine is allowed to start; The multi-threshold protection judgment method is: Determining whether the real-time pressure value is less than a first set limit; If yes, monitor the accelerator pedal opening, and when the accelerator pedal opening is the accelerator pedal opening in the idle state, issue an engine torque limit instruction to limit the maximum output torque of the engine to the set torque extreme value; and at the same time determine whether the real-time pressure value is less than the second set limit value; If so, a shutdown command is issued, and the engine stops running according to the shutdown command.

2. A control strategy for engine protection based on oil monitoring according to claim 1, characterized in that: The engine stops running according to the shutdown instruction, specifically, When the ECU receives the shutdown command, it gradually reduces the engine speed to idle speed with the calibrated shutdown step length; When the engine speed is reduced to the idle speed, the engine is operated at the idle speed for a set time and then the engine is stopped and flamed out.

3. The control strategy for engine protection based on oil monitoring according to claim 2 is characterized in that: The set time is 30s-120s.

4. The control strategy for realizing engine protection based on oil monitoring according to claim 1, characterized in that: When the real-time pressure value is greater than or equal to the first set limit value, the process returns to the step of determining whether the engine is started successfully.

5. The control strategy for realizing engine protection based on oil monitoring according to claim 1, characterized in that: When the real-time pressure value is greater than or equal to the second set limit value, the process returns to the step of determining whether the engine is started successfully.

6. The control strategy for engine protection based on oil monitoring according to claim 1, characterized in that: When the real-time pressure value is less than a first set limit, a low oil pressure indicator light on the instrument panel is activated.

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