An engine lubrication system control method, system, and readable storage medium

Abstract

The application discloses an engine lubrication system control method, system and readable storage medium, the method comprises the following steps: respectively calibrating when a piston cooling nozzle is not activated and activated, obtaining target oil pressure under different engine speeds and engine loads; when the piston cooling nozzle is activated, immediately updating to the target oil pressure corresponding to the activation; when it is detected that the piston cooling nozzle is suddenly activated from the activation, a dynamic adjustment strategy of the target oil pressure is adopted to adjust the target oil pressure; comprising: continuing to maintain the target oil pressure when the piston cooling nozzle is activated for a certain preset time; if the piston cooling nozzle is still in the inactivated state after the preset time ends, gradually transitioning the oil pressure according to the target oil pressure when the piston cooling nozzle is activated and inactivated and a weighting coefficient. The target oil pressure is adjusted and optimized in different life cycles of the engine according to the dynamic performance of the vehicle in real time, so that the optimal power, economy and engine protection of the engine are more reasonably realized.

Description

Technical Field

[0001] This invention relates to the field of engine control, and more particularly to an engine lubrication system control method, system, and readable storage medium. Background Technology

[0002] The engine lubrication system provides lubrication and protection to the various oilers in the engine. An oil pump installed on the engine can change oil pressure and other parameters. To improve engine lubrication and reduce the risk of overheating, it is necessary to control the engine oil pressure at an appropriate level.

[0003] Chinese invention patent CN103758629A discloses a "Method for High-Temperature Protection of Engine Oil Pressure," which reduces output power and thus lowers oil pressure by controlling the current of the torque solenoid valve. However, it does not improve the control method from the perspective of engine lifespan.

[0004] Chinese invention patent CN111350580A discloses "An Engine Cooling System and an Engine Cooling Control Method," which directly compares the target pressure and the actual pressure. Based on the magnitude of these two pressures, it classifies the system into only two operating conditions: when the actual pressure reaches a first preset target pressure and is greater than a second preset target pressure, the control module controls the electronic thermostat to open the first water passage connected to the cooling device until the actual pressure drops to the second preset target pressure; when the actual pressure is less than the second preset target pressure, the control module controls the electronic thermostat to close until the actual pressure reaches the first preset target pressure. However, this entire cooling control system does not improve the control method from the perspective of engine lifespan.

[0005] Therefore, it is urgent to study a lubrication system control method for engines from the perspective of improving engine life, so as to better protect the engine. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to address the deficiencies in the prior art by providing an engine lubrication system control method, system and readable storage medium that can adjust and optimize the target oil pressure in real time according to the dynamic performance of the vehicle at different stages of the engine's life cycle, thereby more rationally achieving optimal engine power, economy and engine protection.

[0007] The technical solution adopted by this invention to solve its technical problem is:

[0008] This invention provides a method for controlling an engine lubrication system, the method comprising:

[0009] Calibration was performed with the piston cooling nozzles inactive and active states to obtain target oil pressures at different engine speeds and loads.

[0010] When the piston cooling nozzle is activated, the target oil pressure is immediately updated to the target oil pressure corresponding to the activation of the piston cooling nozzle;

[0011] When a sudden change from activation to deactivation of the piston cooling nozzle is detected, a dynamic adjustment strategy for the target oil pressure is employed to adjust the target oil pressure; this includes:

[0012] Continue to maintain the target oil pressure when the piston cooling nozzle is activated for a certain preset time; if the piston cooling nozzle is still inactive after the preset time ends, gradually transition the oil pressure according to the target oil pressure when the piston cooling nozzle is activated and inactive, as well as the weighting coefficient; until the difference between the target oil pressure and the target oil pressure when the piston cooling nozzle is inactive is less than a certain threshold, adjust the final target oil pressure to the target oil pressure when the piston cooling nozzle is inactive.

[0013] Furthermore, the calibration method of the present invention includes:

[0014] On the engine test bench, calibration data were obtained for optimal fuel economy under the premise that the piston cooling nozzles are working properly, i.e., knocking is avoided, and VVT performance is normal. Based on the calibration data, tables were established to compare engine speed and engine load with target oil pressure when the piston cooling nozzles are not activated and when they are activated.

[0015] Furthermore, the method for setting the preset time according to the present invention includes:

[0016] The preset time is determined by the engine coolant temperature when the piston cooling nozzle enters the inactive state. The preset time calibration method is as follows: under different engine coolant temperatures, no strong knocking will occur within the preset time when the piston cooling nozzle enters the inactive state from the activated state. This preset time is used as the preset time for the corresponding engine coolant temperature calibration. Strong knocking is defined as the engine knocking and the exit ignition angle exceeding 4°.

[0017] Furthermore, the method for gradually transitioning hydraulic pressure according to the present invention includes:

[0018] The oil pressure is gradually transitioned according to the following formula:

[0019]

[0020] in, For the ultimate target oil pressure, The target oil pressure is determined based on the piston cooling nozzle's inactivity as found during calibration. The target oil pressure when the piston cooling nozzle is activated is obtained from the calibration; where k is a weighting coefficient, and the formula for calculating k is as follows:

[0021]

[0022] in, The weighting coefficients for the (N+1)th sampling period are... The weighting coefficients are for the Nth sampling period, where N = 0, 1, 2, 3, ..., meaning the weighting coefficients are updated once after each sampling period. =0; These are the basic values ​​of the weighting coefficients. This is a correction factor.

[0023] Furthermore, the method for determining the correction factor of the present invention includes:

[0024]

[0025] The coefficient k1 is based on the number of injections and the value of (original target oil pressure - actual oil pressure) / target oil pressure. A calibration table for determining the coefficient k1;

[0026] The coefficient k2 is based on the octane rating of the fuel and the engine retraction strength coefficient. A calibration table for determining the coefficient k2; The ignition angle is delayed due to the current detonation. Maximum permissible ignition angle delayed for detonation;

[0027] The coefficient k3 is determined from the calibration table based on engine speed and water temperature;

[0028] By consulting the calibration table, the values ​​of coefficients k1, k2, and k3 under different parameter conditions can be obtained.

[0029] Furthermore, the method of the present invention also includes a method for real-time updating of the values ​​of coefficients k1, k2, and k3, wherein the update conditions are as follows:

[0030] The engine speed is in the range of 850rpm to 6000rpm, and the engine speed fluctuation range is ±20rpm;

[0031] The engine load is in the range of 150 mgpl to 3000 mgpl, and the engine load fluctuation range is ±15 mgpl;

[0032] The engine coolant temperature ranges from -45℃ to 100℃, with a fluctuation range of ±2℃.

[0033] The actual oil pressure fluctuation range is ±2kPa;

[0034] The ignition angle efficiency is between 0.5 and 1, and the ignition angle fluctuation range is within ±0.1.

[0035] The engine requires that the fluctuation of the firing torque be within ±2%.

[0036] The engine requires that the torque fluctuation in the air passage be within ±2%.

[0037] The intake air temperature fluctuation range is within ±3℃;

[0038] The vehicle speed fluctuation range is within ±2km / h;

[0039] The engine did not experience knocking;

[0040] The number of injections (CNT) remained unchanged.

[0041] The octane rating of the oil product has not been updated for more than 60 minutes;

[0042] No coefficients k1, k2, or k3 were updated during this driving cycle;

[0043] The corresponding vehicle mileage exceeds the preset mileage S, which is continuously updated and stored when the vehicle is powered off.

[0044] Only after all the above conditions are met simultaneously and the maintenance time exceeds T are the coefficients k1, k2, and k3 allowed to be updated; otherwise, updates are not allowed, and the conditions will be re-evaluated for the next update of coefficients k1, k2, and k3.

[0045] Furthermore, the method for updating coefficient k1 according to the present invention includes:

[0046] If the current coefficient k1 minus the current coefficient k2 is greater than the preset value, and the current coefficient k1 minus the current coefficient k3 is greater than the preset value, then the final weighted coefficient k is immediately added to a certain difference D1 to obtain the updated coefficient k';

[0047] If no strong knocking occurs after the coefficient k' is updated, then in subsequent driving cycles, the coefficient k1 under the same conditions will be subtracted from D1 to obtain the new coefficient k1'; that is, the current condition coefficient k1 is updated, and the new coefficient k1' is used as the injection frequency CNT. For the corresponding calibrated coefficients, the preset mileage S under the same working conditions is updated to 1.1S; otherwise, the coefficient k1 under the current working conditions is not updated, and the preset mileage S is not updated.

[0048] Furthermore, the method for updating coefficients k2 and k3 according to the present invention includes:

[0049] If the current coefficient k2 minus the current coefficient k1 is greater than the preset value, and the current coefficient k3 minus the current coefficient k1 is greater than the preset value, then the final weighted coefficient k is immediately subtracted by a certain difference D2 to obtain a new coefficient k'.

[0050] If the engine does not experience knocking after the coefficient k' is updated, then the coefficient k3 encountered in the subsequent driving cycle under the same conditions will be subtracted by D2 to obtain the new coefficient k3'; if the coefficient k3 under the same conditions is updated and the number of injections CNT1 exceeds the preset value, then the coefficient k2 will be updated, and the coefficient k2 before the update will be subtracted by D2 to obtain the new coefficient k2'; immediately after the coefficient k2 is updated, the number of injections CNT1 will be cleared to zero, and the accumulation will start again after the coefficient k3 is updated again; and the preset mileage S under the same conditions will be updated to 1.05S;

[0051] If the engine only experiences mild knocking after the update, the coefficient k3 encountered in subsequent driving cycles under the same conditions will be reduced by k*D2 to obtain the new coefficient k3', and the preset mileage S under the same conditions will be updated to 1.1S. Under this condition, if the number of injections CNT2 exceeds the preset value, the coefficient k2 will be updated by subtracting k*D2 from the previous coefficient k2 to obtain the new coefficient k2'. Immediately after the coefficient k2 is updated, the number of injections CNT2 will be cleared to zero, and the accumulation will start again after the coefficient k3 is updated again. Otherwise, neither the coefficients k2 nor k3 will be updated, and the preset mileage S will not be updated.

[0052] This invention provides an engine lubrication system control system, comprising:

[0053] The engine condition monitoring module is used to detect engine speed, engine torque, engine load, engine ignition efficiency, injection frequency, fuel octane number, and knock occurrence.

[0054] The cylinder intake monitoring module is used to detect the cylinder intake temperature and intake density.

[0055] Vehicle speed sensor is used to detect the current speed of the vehicle;

[0056] Engine oil pressure sensor, used to detect the real-time pressure of engine oil;

[0057] An engine oil pressure controller is used to receive and process detection data sent by the engine operating condition monitoring module, cylinder intake monitoring module, vehicle speed sensor and engine oil pressure sensor, and to perform control according to the engine lubrication system control method as described in any one of claims 1 to 8.

[0058] The present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the engine lubrication system control method as described in any one of claims 1 to 8.

[0059] The beneficial effects of this invention are:

[0060] 1. This invention proposes an engine lubrication system control method from the perspective of improving engine life;

[0061] 2. This invention calibrates the piston cooling nozzles when they are not activated and when they are activated to obtain target oil pressures under different engine speeds and engine loads, and proposes a method for obtaining target oil pressures.

[0062] 3. In order to avoid the impact of sudden drop in oil pressure on engine lubrication, and also to avoid the impact of oil pressure control fluctuations when the oil pressure drops, this invention proposes a dynamic adjustment strategy for target oil pressure, which gradually transitions the oil pressure based on the target oil pressure when the piston cooling nozzle is activated and deactivated, as well as the weighting coefficient.

[0063] 4. In the dynamic adjustment strategy of target oil pressure, the coefficients of the engine at different life cycles can be learned and updated in real time according to the dynamic performance of the vehicle, which can better adapt to various different environments.

[0064] In summary, in the method of the present invention, the target oil pressure can be adjusted and optimized in real time according to the dynamic performance of the vehicle under different life cycles of the engine, thereby more rationally achieving optimal engine power, economy and engine protection. Attached Figure Description

[0065] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0066] Figure 1 This is a flowchart of a thermal management system control method for improving engine life according to an embodiment of the present invention.

[0067] Figure 2 This is a control flowchart of an embodiment of the present invention when the activation of the piston cooling nozzle suddenly changes to the deactivation of the piston cooling nozzle.

[0068] Figure 3 This is a flowchart illustrating the update process of coefficient k1 in an embodiment of the present invention.

[0069] Figure 4 This is a flowchart illustrating the update process of coefficients k2 and k3 in an embodiment of the present invention. Detailed Implementation

[0070] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0071] Example 1

[0072] like Figure 1 As shown in the figure, an embodiment of the present invention proposes a control method for an engine lubrication system. The method includes: a method for obtaining a target oil pressure; and dynamic adjustment conditions and methods for the target oil pressure.

[0073] Under normal operating conditions, the target oil pressure is determined based on engine speed and engine load (engine load can be characterized by actual fresh air intake density, which refers to the actual fresh air intake density entering the cylinder). This target oil pressure is obtained on the engine test bench based on the optimal fuel economy under the premise that the piston cooling nozzles are working properly (to avoid knocking) and the VVT ​​performance is normal.

[0074] Based on this, 1) when the piston cooling nozzle is not activated (not activated means the piston cooling nozzle is not working, i.e., it does not need to be turned on for piston cooling), the calibration data in this example is as follows:

[0075]

[0076] 2) When the piston cooling nozzle is activated, the calibration data for this example is as follows:

[0077]

[0078] Example 2

[0079] This invention provides a dynamic adjustment strategy for the target oil pressure. When the piston cooling nozzle is activated, the target oil pressure is immediately updated to the level corresponding to when the piston cooling nozzle is activated. However, when the piston cooling nozzle changes from activated to deactivated, to avoid the potential impact of a sudden drop in oil pressure on engine lubrication, and also to avoid the impact of oil pressure control fluctuations that occur when the oil pressure drops, the control of oil pressure changes is optimized.

[0080] like Figure 2 As shown, when the piston cooling nozzle activation abruptly changes to piston cooling nozzle deactivation:

[0081] The first step is to maintain the oil pressure at the preset time t1 when the piston cooling nozzles are activated; this maintains a high oil pressure to prevent further increase in engine heat load. The preset time t1 depends on the engine coolant temperature when the piston cooling nozzles just enter the inactive state. Its calibration is based on the assumption that no strong knocking occurs within the preset time t1 from activation to inactivation of the piston cooling nozzles (strong knocking is defined as engine knocking causing the ignition angle to drop by more than 4°). Based on this, this example uses:

[0082]

[0083] The second step, if the piston cooling nozzles are still inactive after the first step, gradually transition the oil pressure according to the following formula:

[0084]

[0085] in, For the ultimate target oil pressure, The target oil pressure is the one found in the table above when the piston cooling nozzle is not activated. This refers to the target oil pressure when the piston cooling nozzle is activated, as found in the table above. Where k is a weighting coefficient, determined as follows:

[0086]

[0087] in, The weighting coefficients for the (N+1)th sampling period are... These are the weighting coefficients for the Nth sampling period, where N = 0, 1, 2, 3… The sampling period is 10 ms, meaning the weighting coefficients are updated after every one sampling period. Specifically, The weighting coefficient is 0 when we just enter the second step. The basic value for the weighting coefficient is 0.2 in this example, while... Correction factor:

[0088]

[0089] Example 3

[0090] This invention provides a method for determining coefficients k1, k2, and k3.

[0091] 1) Based on the number of injections (CNT, i.e., the number of injections that the cylinder will perform during the compression and ignition strokes) and the ratio of the difference between the original target oil pressure and the actual oil pressure to the target oil pressure. Determine k1. The fewer the number of sprays, the better. A higher oil pressure can cause oil dilution, requiring a rapid reduction in oil pressure.

[0092] The calibration values ​​of this invention are as follows:

[0093]

[0094] 2) Based on the octane rating coefficient of the oil (i.e., the octane number of the oil) and engine retraction strength coefficient ( The ignition angle is delayed due to the current detonation. Determine k2 for the maximum permissible ignition angle for detonation delay (10° in this example).

[0095] Detonation angle strength coefficient The higher the octane rating, the stronger the knocking. To suppress knocking, a higher oil pressure is required. The lower the octane rating, the worse the oil quality. To reduce the possibility of knocking, a higher oil pressure is required.

[0096] The calibration values ​​of this invention are as follows:

[0097]

[0098] 3) Determine k3 based on engine speed and coolant temperature. The higher the engine speed or the higher the coolant temperature, the greater the risk of engine knocking, and thus a higher oil pressure is required.

[0099] The calibration values ​​of this invention are as follows:

[0100]

[0101] Once it occurs and If the difference is within ±2 kPa, then the final target oil pressure is taken as target oil pressure p1. Exit step two and proceed to step three.

[0102] The third step is to take the target oil pressure when the piston cooling nozzle is not activated after the second step.

[0103] Example 4

[0104] This invention provides a method for real-time updating of coefficients k1, k2, and k3.

[0105] In this embodiment of the invention, the coefficients k1, k2, and k3 are updated in real time and stored after the vehicle is powered off, in order to adapt to dynamic adjustments and optimizations under different life cycles of the engine, thereby more reasonably achieving optimal engine power, economy, and engine protection.

[0106] The following details the update method for coefficients k1, k2, and k3. The update is performed under steady-state engine conditions, and the following conditions must be met simultaneously for each target oil pressure to be updated:

[0107] 1. The engine speed is within the preset range, which is 850rpm~6000rpm in this example, and the engine speed fluctuation range is ±20rpm;

[0108] 2. The engine load is within the preset range, which in this example is 150mgpl~3000mgpl, and the engine load fluctuation range is ±15mgpl;

[0109] 3. The engine coolant temperature is within the preset range, which in this example is -45℃ to 100℃, with a fluctuation range of ±2℃;

[0110] 4. The actual oil pressure fluctuation range is ±2kPa;

[0111] 5. The ignition angle efficiency is within the preset range, which is 0.5~1 in this example, and the ignition angle fluctuation range is within ±0.1.

[0112] 6. The engine requires that the fluctuation of the firing torque be within ±2%;

[0113] 7. The engine requires that the torque fluctuation in the air passage be within ±2%;

[0114] 8. Intake pressure fluctuation range is within ±3℃;

[0115] 9. Vehicle speed fluctuation range is within ±2km / h;

[0116] 10. No detonation occurred;

[0117] 11. The number of injections (CNT) remained unchanged;

[0118] 12. The octane rating of the oil product has not been updated for more than the preset time; in this example, it is set to 60 minutes.

[0119] 13. No coefficients among k1, k2, and k3 were updated in this driving cycle;

[0120] 14. The vehicle mileage corresponding to the coefficients k1, k2, and k3 not being updated exceeds the preset mileage S. In this example, the initial mileage is set to 100km, and the preset mileage S will be continuously updated and stored when the vehicle is powered off.

[0121] Only after all the above conditions are met simultaneously and the duration exceeds T (5s in this example) is it permissible to update the coefficients k1, k2, k3. Otherwise, updates are not allowed. The next time coefficients k1, k2, k3 are updated, it is necessary to re-evaluate whether the conditions are met before updating the coefficients k1, k2, k3 can be updated again.

[0122] The same operating conditions in this technology are defined as follows: engine speed deviation within ±20 rpm, load deviation within ±15 mgpl, ignition efficiency deviation within ±0.1, engine requested ignition torque within ±2%, oil pressure deviation within ±2 kPa, water temperature deviation within ±2℃, injection frequency CNT unchanged, knock angle deviation within ±1°, and octane rating deviation within ±0.05.

[0123] It should be noted that the current operating condition refers to the same average engine speed, average load, average ignition efficiency, average engine requested torque, average oil pressure deviation, average coolant temperature deviation, average knock angle deviation, average octane number deviation, and injection frequency (CNT) under the current stable conditions.

[0124] Example 5

[0125] This invention provides a method for updating coefficients k1, k2, and k3.

[0126] like Figure 3 As shown, the update process for coefficient k1 in this embodiment of the invention is as follows:

[0127] 1) If the current coefficient k1 minus the current coefficient k2 is greater than the preset value (0.2 in this example), and the current coefficient k1 minus the current coefficient k3 is greater than the preset value (0.2 in this example), then the final executed coefficient k (the final executed coefficient k is the minimum value among coefficients k1, k2, and k3) is immediately added to a certain difference D1 (0.1 in this example) to obtain a new coefficient k'.

[0128] 1.1) If no strong knock occurs after the update (in this example, strong knock is defined as a delay in ignition angle exceeding 4° after knock), then subtract D1 from the coefficient k1 encountered under the same conditions in subsequent driving cycles to obtain the new coefficient k1'. That is, the current condition coefficient k1 is updated, and the new coefficient k1' is used as the injection frequency CNT. With the corresponding coefficient, the preset mileage S under the same working conditions is replaced with 1.1 times the previous value.

[0129] 1.2) In other cases, the coefficient k1 under the current operating condition will not be updated. When the same operating condition is encountered again, the operating condition coefficient k1 before the update will be used, and the preset mileage S under the same operating condition will not be updated.

[0130] like Figure 3 As shown, the update process for coefficients k2 and k3 in this embodiment of the invention is as follows:

[0131] 2) If the current coefficient k2 minus the current coefficient k1 is greater than the preset value (0.2 in this example), and the current coefficient k3 minus the current coefficient k1 is greater than the preset value (0.2 in this example), then the final executed coefficient k (the final executed coefficient k is the minimum value among coefficients k1, k2, and k3) is immediately subtracted by a certain difference D2 (0.1 in this example) to obtain a new coefficient k'.

[0132] 2.1) If the engine does not experience knocking after the update, the coefficient k3 encountered in subsequent driving cycles under the same conditions will be reduced by D2 to obtain the new coefficient k3'. That is, coefficient k3 is updated, and the new coefficient k3' is used after the update. If the number of times coefficient k3 is updated under the same conditions, CNT1, exceeds the preset value (50 times in this example), coefficient k2 will be updated by subtracting D2 from the previous coefficient k2 to obtain the new coefficient k2'. Immediately after coefficient k2 is updated, the update count CNT1 is reset to zero, and the accumulation restarts after coefficient k3 is updated again. The preset mileage S under the same conditions is replaced with 1.05 times the previous value.

[0133] 2.2) If the engine only experiences weak knocking after the update (weak knocking is defined as a retardation of the ignition angle exceeding 2° after knocking), then the coefficient k3 encountered in subsequent driving cycles under the same operating conditions is subtracted by k*D2 to obtain the new coefficient k3'. In this example, the multiplication factor k is 0.6. That is, once the coefficient k3 for the current corresponding operating condition is updated, the new coefficient k3' is used under the same operating conditions, and the preset mileage S under the same operating conditions is replaced with 1.1 times the value before the update. Under this condition, if the number of times coefficient k3 is updated under the same operating conditions, CNT2, exceeds the preset value (CNT2 is not less than CNT1; due to knocking, coefficient k2 needs to be adjusted more cautiously to protect the engine; the larger CNT2 is, the lower the target oil pressure update frequency; in this example, it is 100 times), then coefficient k2 is updated. The update method is to subtract k*D2 from the coefficient k2 before the update to obtain the new coefficient k2'. Immediately after coefficient k2 is updated, the update count CNT2 is cleared to zero, and the accumulation starts again after coefficient k3 is updated again.

[0134] 2.3) In other cases, the coefficients k2 and k3 will not be updated when the same driving condition is encountered in subsequent driving cycles. When the same driving condition is encountered again, the coefficients k2 and k3 before the update will be used, and the preset mileage S under the same driving condition will not be updated.

[0135] The above completes the self-learning update of coefficients k1, k2, k3 and preset mileage S. In subsequent new driving cycles, the updated coefficients k1, k2, k3 and preset mileage S are used to control the target oil pressure and determine the target oil pressure update mileage conditions.

[0136] Finally, the updated coefficients k1, k2, and k3 are taken as the minimum value to obtain the final target oil pressure. The oil pump is controlled according to the difference between the target oil pressure and the actual oil pressure so that the actual oil pressure follows the target oil pressure, thereby completing the control of the engine thermal management system.

[0137] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0138] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A control method for an engine lubrication system, characterized in that, The method includes: Calibration was performed with the piston cooling nozzles inactive and active states to obtain target oil pressures at different engine speeds and loads. When the piston cooling nozzle is activated, the target oil pressure is immediately updated to the target oil pressure corresponding to the activation of the piston cooling nozzle; When a sudden change from activation to deactivation of the piston cooling nozzle is detected, a dynamic adjustment strategy for the target oil pressure is employed to adjust the target oil pressure; this includes: Continue to maintain the target oil pressure when the piston cooling nozzle is activated for a certain preset time; if the piston cooling nozzle is still inactive after the preset time ends, gradually transition the oil pressure according to the target oil pressure when the piston cooling nozzle is activated and inactive, as well as the weighting coefficient; until the difference between the target oil pressure and the target oil pressure when the piston cooling nozzle is inactive is less than a certain threshold, adjust the final target oil pressure to the target oil pressure when the piston cooling nozzle is inactive.

2. The engine lubrication system control method according to claim 1, characterized in that, The calibration method includes: On the engine test bench, calibration data were obtained for optimal fuel economy under the premise that the piston cooling nozzles are working properly, i.e., knocking is avoided, and VVT performance is normal. Based on the calibration data, tables were established to compare engine speed and engine load with target oil pressure when the piston cooling nozzles are not activated and when they are activated.

3. The engine lubrication system control method according to claim 1, characterized in that, The method for setting the preset time includes: The preset time is determined by the engine coolant temperature when the piston cooling nozzle enters the inactive state. The preset time calibration method is as follows: under different engine coolant temperatures, no strong knocking will occur within the preset time when the piston cooling nozzle enters the inactive state from the activated state. This preset time is used as the preset time for the corresponding engine coolant temperature calibration. Strong knocking is defined as the engine knocking and the exit ignition angle exceeding 4°.

4. The engine lubrication system control method according to claim 1, characterized in that, The method for gradually transitioning hydraulic pressure includes: The oil pressure is gradually transitioned according to the following formula: in, For the ultimate target oil pressure, The target oil pressure is determined based on the piston cooling nozzle's inactivity as found during calibration. The target oil pressure when the piston cooling nozzle is activated is obtained from the calibration; where k is a weighting coefficient, and the formula for calculating k is as follows: in, The weighting coefficients for the (N+1)th sampling period are... The weighting coefficients are for the Nth sampling period, where N = 0, 1, 2, 3, ..., meaning the weighting coefficients are updated once after each sampling period. =0; These are the basic values ​​of the weighting coefficients. This is a correction factor.

5. The engine lubrication system control method according to claim 4, characterized in that, The method for determining the correction factor includes: The coefficient k1 is based on the number of injections and the value of (original target oil pressure - actual oil pressure) / target oil pressure. A calibration table for determining the coefficient k1; The coefficient k2 is based on the octane rating of the fuel and the engine retraction strength coefficient. A calibration table for determining the coefficient k2; The ignition angle is delayed due to the current detonation. Maximum permissible ignition angle delayed for detonation; The coefficient k3 is determined from the calibration table based on engine speed and water temperature; By consulting the calibration table, the values ​​of coefficients k1, k2, and k3 under different parameter conditions can be obtained.

6. The engine lubrication system control method according to claim 5, characterized in that, This method also includes a method for real-time updating of the values ​​of coefficients k1, k2, and k3, with the following update conditions: The engine speed is in the range of 850rpm to 6000rpm, and the engine speed fluctuation range is ±20rpm; The engine load is in the range of 150 mgpl to 3000 mgpl, and the engine load fluctuation range is ±15 mgpl; The engine coolant temperature ranges from -45℃ to 100℃, with a fluctuation range of ±2℃. The actual oil pressure fluctuation range is ±2kPa; The ignition angle efficiency is between 0.5 and 1, and the ignition angle fluctuation range is within ±0.

1. The engine requires that the fluctuation of the firing torque be within ±2%. The engine requires that the torque fluctuation in the air passage be within ±2%. The intake air temperature fluctuation range is within ±3℃; The vehicle speed fluctuation range is within ±2km / h; The engine did not experience knocking; The number of injections (CNT) remained unchanged. The octane rating of the oil product has not been updated for more than 60 minutes; No coefficients k1, k2, or k3 were updated during this driving cycle; The corresponding vehicle mileage exceeds the preset mileage S, which is continuously updated and stored when the vehicle is powered off. Only after all the above conditions are met simultaneously and the duration exceeds T can the coefficients k1, k2, and k3 be updated. Otherwise, updates are not allowed. The next time coefficients k1, k2, and k3 are updated, the conditions will be re-evaluated to determine if they are met.

7. The engine lubrication system control method according to claim 6, characterized in that, Methods for updating coefficient k1 include: If the current coefficient k1 minus the current coefficient k2 is greater than the preset value, and the current coefficient k1 minus the current coefficient k3 is greater than the preset value, then the final weighted coefficient k is immediately added to a certain difference D1 to obtain the updated coefficient k'; If no strong knocking occurs after the coefficient k' is updated, then in subsequent driving cycles, the coefficient k1 under the same conditions will be subtracted from D1 to obtain the new coefficient k1'; that is, the current condition coefficient k1 is updated, and the new coefficient k1' is used as the injection frequency CNT. For the corresponding calibrated coefficients, the preset mileage S under the same operating conditions is updated to 1.1S; otherwise, the coefficient k1 under the current operating conditions is not updated, and the preset mileage S is not updated.

8. The engine lubrication system control method according to claim 6, characterized in that, Methods for updating coefficients k2 and k3 include: If the current coefficient k2 minus the current coefficient k1 is greater than the preset value, and the current coefficient k3 minus the current coefficient k1 is greater than the preset value, then the final weighted coefficient k is immediately subtracted by a certain difference D2 to obtain a new coefficient k'. If the engine does not experience knocking after the coefficient k' is updated, then the coefficient k3 encountered in the subsequent driving cycle under the same conditions will be subtracted by D2 to obtain the new coefficient k3'; if the coefficient k3 under the same conditions is updated and the number of injections CNT1 exceeds the preset value, then the coefficient k2 will be updated, and the coefficient k2 before the update will be subtracted by D2 to obtain the new coefficient k2'; immediately after the coefficient k2 is updated, the number of injections CNT1 will be cleared to zero, and the accumulation will start again after the coefficient k3 is updated again; and the preset mileage S under the same conditions will be updated to 1.05S; If the engine only experiences mild knocking after the update, the coefficient k3 encountered in subsequent driving cycles under the same conditions will be reduced by k*D2 to obtain the new coefficient k3', and the preset mileage S under the same conditions will be updated to 1.1S. Under this condition, if the number of injections CNT2 exceeds the preset value, the coefficient k2 will be updated by subtracting k*D2 from the previous coefficient k2 to obtain the new coefficient k2'. Immediately after the coefficient k2 is updated, the number of injections CNT2 will be cleared to zero, and the accumulation will start again after the coefficient k3 is updated again. Otherwise, neither the coefficients k2 nor k3 will be updated, and the preset mileage S will not be updated.

9. A control system for an engine lubrication system, characterized in that, include: The engine condition monitoring module is used to detect engine speed, engine torque, engine load, engine ignition efficiency, injection frequency, fuel octane number, and knock occurrence. The cylinder intake monitoring module is used to detect the cylinder intake temperature and intake density. Vehicle speed sensor is used to detect the current speed of the vehicle; Engine oil pressure sensor, used to detect the real-time pressure of engine oil; An engine oil pressure controller is used to receive and process detection data sent by the engine operating condition monitoring module, cylinder intake monitoring module, vehicle speed sensor and engine oil pressure sensor, and to perform control according to the engine lubrication system control method as described in any one of claims 1 to 8.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the engine lubrication system control method as described in any one of claims 1 to 8.

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