An engine oil pressure sensor failure post-processing method

Abstract

The application discloses a method for post-processing of a machine oil pressure sensor fault, which comprises machine oil pump control optimization, engine maximum torque limitation, engine cooling water target water temperature change rate limitation, engine target VVT phase change rate limitation and piston cooling nozzle state prolongation, realizes improvement of machine oil pressure control after the machine oil pressure sensor fault, and simultaneously optimizes maximum engine torque, limits VVT phase and water temperature change rate and piston cooling nozzle working state, so that the engine is further protected.

Description

Technical Field

[0001] This invention relates to the field of engine control technology, and more specifically to a method for handling oil pressure sensor malfunctions. Background Technology

[0002] An engine is a power source that converts chemical energy into mechanical energy through combustion, generating a large amount of heat in the process. From the perspectives of power, economy, and emissions performance, engines ideally operate at their optimal temperature, thus requiring a suitable cooling system. Engine oil, the fluid in the cooling system, plays a vital role in lubrication and friction reduction, assisting in cooling, sealing against leaks, preventing rust and corrosion, and damping shocks; it is often referred to as the "blood" of a car.

[0003] The gasoline engine oil pressure sensor provides feedback on the oil pressure signal for oil pressure control. Low oil pressure can cause poor lubrication of the crankshaft, connecting rods, and camshaft bearings, potentially leading to abnormal engine noise, unstable operation, and reduced power. Secondly, poor lubrication of critical friction points can cause localized overheating. If the engine continues to operate under conditions of low oil pressure, it can lead to serious damage, such as bearing failure, preventing the engine from starting and requiring bearing scraping or replacement. Conversely, excessive oil pressure can easily cause oil leaks and may lead to the oil filter bursting or detaching. Therefore, it is crucial to maintain the engine oil pressure at an appropriate level. However, if the oil pressure sensor malfunctions, oil pressure control cannot enter closed-loop control. Summary of the Invention

[0004] The purpose of this invention is to provide a method for handling oil pressure sensor failures, so as to ensure maximum engine power output while protecting the engine, and at the same time guaranteeing personal safety and vehicle lifespan.

[0005] To solve the above-mentioned technical problems, the present invention provides a technical solution: a method for handling oil pressure sensor failures, the method comprising the following steps:

[0006] The engine speed is obtained, and the value of the oil pump control percentage is determined based on the relationship between the engine speed and the upper and lower limits of the preset engine dual-mass flywheel resonance speed band. The oil pump control percentage ranges from 0% to 100%. A control percentage of 0% means no increase in oil pressure, while a control percentage of 100% means the oil pump increases oil pressure at its maximum capacity.

[0007] The characteristic value of the coolant temperature is obtained based on the target and actual coolant temperature of the engine. The maximum torque optimization coefficient of the engine is obtained based on the pre-calibrated relationship between the coolant temperature and the maximum torque optimization coefficient of the engine. Then, the maximum torque of the engine is reduced based on the maximum torque optimization coefficient of the engine.

[0008] The rate of change of the target coolant temperature of the engine is limited to not exceed a preset value;

[0009] The rate of change of the target VVT phase of the engine is limited to a preset value.

[0010] According to the above scheme, when the engine speed is less than the upper limit of the engine's dual-mass flywheel resonance speed band, the oil pump control percentage (pct) is set. OilPump It is 100%;

[0011] When the engine speed is greater than the upper limit of the engine's dual-mass flywheel resonance speed band, but less than a certain preset value, the oil pump control percentage (pct) is activated. OilPump Represented as,

[0012] pct OilPump =100%×f(n,T) CoolantAct )×f(T Amb ,p Amb )×f(T CoolantStart ,Cnt Com )

[0013] In the above formula, f(n,T) CoolantAct The actual water temperature T of the engine coolant CoolantAct And obtained by calibrating the engine speed n; f(T) Amb ,p Amb (Through atmospheric temperature T) Amb and atmospheric pressure p Amb The calibration yielded f(T) CoolantStart ,Cnt Com The temperature T of the coolant during engine start-up CoolantStart and the number of combustion cycles (Cnt) during engine start-up Com The calibration was obtained;

[0014] When the engine speed exceeds a certain preset value, the oil pump control percentage (pct) is then activated. OilPump Represented as,

[0015]

[0016] In the above formula, the feedforward part Pct FF It is represented as follows,

[0017]

[0018] In the above formula, f(n,p) OilDesird During bench calibration, the engine speed n and target oil pressure P are used as the references. OilDesird Calibration yielded; Pct PistonCoolingDetermined by the activation state of the piston cooling nozzle, f(T) Oil According to the oil temperature T Oil The calibration was obtained;

[0019] f(n diff ,dn diff ) is the speed difference correction factor, which is based on the engine speed difference n diff The rate of change of engine speed difference dn diff The calibration yielded the engine speed difference n. diff The difference between the target engine speed and the actual engine speed, dn is the rate of change of the engine speed difference. diff For n diff The first derivative; when the engine is not under closed-loop control, f(n) diff ,dn diff The value of ) is 1;

[0020] This is the VVT ​​phase difference correction factor, which is based on the engine speed n and the VVT ​​control characteristic value. The calibration was obtained; The value is determined by the target VVT phase phi VVTDsrd and actual VVT phase phi VVTAct Decision: When VVT control is not a closed-loop control. The value is 1;

[0021] This is a cooling water temperature difference correction factor, which is based on the characteristic value of the cooling water temperature. Engine speed n is obtained through calibration; Coolant temperature characteristic value The target water temperature T of the engine coolant CoolantDsrd Actual water temperature T CoolantAct Decide.

[0022] r Adapt r is the self-learning correction coefficient. Adapt It updates through self-learning.

[0023] According to the above plan, Pct PistonCooling The specific value selection method is as follows;

[0024] When the piston cooling nozzles are not activated, Pct PistonCooling =C0, where C0 is the preset percentage;

[0025] When the piston cooling nozzle is activated, Pct PistonCooling (n+1)=Pct PistonCooling (n)+C,Pct PistonCooling (n), Pct PistonCooling (n+1) represent the Pct values ​​of the update cycle for the activation state of the nth and (n+1)th piston cooling nozzles, respectively.PistonCooling The increment C is a preset percentage, and n = 0, 1, 2...

[0026] According to the above scheme, if the engine only has intake VVT, then the target VVT phase phi VVTDsrd and actual VVT phase phi VVTAct The input is the intake VVT; if the engine only has an exhaust VVT, then the target VVT phase phi VVTDsrd and actual VVT phase phi VVTAct The input is the exhaust VVT; if the engine has both intake VVT ​​and exhaust VVT, then the target VVT phase phi VVTDsrd and actual VVT phase phi VVTAct The input is the larger of the intake VVT ​​and exhaust VVT.

[0027] According to the above scheme, when in self-learning mode and meeting the self-learning advancement conditions, r Adapt Perform self-learning updates;

[0028] After entering self-learning update mode, calculate the average engine speed, average engine load, average target coolant temperature, piston cooling nozzle status, average oil temperature, and VVT control characteristic value within a preset time t2. Average value, characteristic value of cooling water temperature The average value is calculated as follows: if an intake VVT ​​phase exists within time t2, the average value of the intake VVT ​​phase within t2 is calculated; if an exhaust VVT phase exists within t2, the average value of the exhaust VVT phase within t2 is calculated. The average operating condition is defined as follows: if the average engine speed, average engine load, average coolant target temperature, piston cooling nozzle status, average oil temperature, average intake VVT ​​phase, and average exhaust VVT phase are all the same across two time periods t2, then the vehicle is considered to be operating under the same average condition at the two different times. The r values ​​under different average conditions... Adapt Store and update independently;

[0029] r Adapt The update method is as follows:

[0030] If within t2, The average value is less than -0.05, and If the average value is >0.08, then r under this average working condition... Adapt Updated to r Adapt =r Adapt (z)+0.005;r Adapt (z) represents the self-learning correction coefficient before the update;

[0031] If within t2, The average value is less than -0.05, and If the average value is >0.03, then r under this average working condition is... Adapt Updated to r Adapt =r Adapt (z)+0.004;

[0032] If within t2, The average value is less than -0.05, and If the average value is >0.01, then r under this average working condition is... Adapt Updated to r Adapt =r Adapt (z)+0.003;

[0033] If within t2, If the average value is ≤ -0.01, then r under this average working condition is... Ad apt updated to r Adapt =r Adapt (z)+0.0025;

[0034] If within t2, The average value is ≤0.01, and If the average value is >0.01, then r under this average working condition is... Adapt Updated to r Adapt =r Adapt (z)+0.002;

[0035] If within t2, The average value is ≤0.01, and If the average value is less than -0.01, then r under this average working condition is... Adapt Updated to r Adapt =r Adapt (z)+0.001;

[0036] If within t2 Average and If the average value does not meet any of the above conditions, then the r value under the average working condition shall be... Adapt Updated to r Adapt =r Adapt (z).

[0037] According to the above scheme, the self-learning working condition is defined as follows.

[0038] 1) The engine speed is within the preset range, and the engine speed fluctuation after entering the self-learning update is within the preset range;

[0039] 2) The fluctuation in the density of fresh air entering the cylinder is within the preset range;

[0040] 3) The oil temperature fluctuation is within the preset range;

[0041] 4) The target temperature fluctuation of the engine coolant is within the preset range;

[0042] 5) VVT closed-loop control activated; Specifically, if the engine only has intake VVT, then only the control status of intake VVT ​​is judged; if the engine only has exhaust VVT, then only the control status of exhaust VVT is judged; if the engine has both intake VVT ​​and exhaust VVT, then both intake VVT ​​and exhaust VVT should be in the closed-loop control activated state.

[0043] 6) The target VVT phase fluctuation of the engine is within the preset range; specifically, if the engine only has intake VVT, then only the intake VVT ​​angle is judged; if the engine only has exhaust VVT, then only the exhaust VVT angle is judged; if the engine has both intake VVT ​​and exhaust VVT, then both intake VVT ​​phase fluctuation and exhaust VVT phase fluctuation should be within the preset range.

[0044] 7) The activation state of the piston cooling nozzles remained unchanged;

[0045] 8) No engine knocking occurred;

[0046] 9) No pre-ignition occurred in the engine;

[0047] When all of the above conditions are met, the vehicle is considered to be in self-learning mode.

[0048] According to the above plan, the conditions for self-learning advancement are as follows;

[0049] 1) The vehicle is continuously in self-learning mode for no less than the preset time t1;

[0050] 2) The number of driving cycles without updating the self-learning correction coefficient exceeds the preset number;

[0051] When all of the above conditions are met, the vehicle is deemed to meet the self-learning advancement conditions.

[0052] According to the above plan, the specific method to reduce the engine's maximum torque is as follows: based on the target coolant temperature T of the engine. CoolantDsrd Actual water temperature T CoolantAct Determine the characteristic value of cooling water temperature Based on cooling water temperature characteristic value Determine the engine maximum torque optimization coefficient k MaxTrq The engine's maximum torque optimization coefficient k MaxTrq The optimized maximum engine torque is obtained by multiplying the maximum torque by the engine's maximum torque; where the coolant temperature characteristic value is... With the engine maximum torque optimization coefficient k MaxTrq The relationship is obtained through pre-calibration.

[0053] According to the above scheme, the preset duration of the delay piston cooling nozzle opening and closing state is t3. t3 is obtained based on the maximum value of the delayed ignition angle after knocking when the original piston cooling nozzle was open in the previous state of the vehicle, and the octane number coefficient.

[0054] A computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the oil pressure sensor failure handling method described above.

[0055] The beneficial effects of this invention are: when the oil pressure sensor malfunctions and the engine is unable to perform closed-loop oil pressure control, the oil pressure control is improved and the engine is protected by intervening in the oil pump control, the engine maximum torque, the target coolant temperature change rate, and the engine target VVT phase change rate. Attached Figure Description

[0056] Figure 1 This is a flowchart of the oil pressure sensor failure handling method according to Embodiment 1 of the present invention. Detailed Implementation

[0057] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the described embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0058] Example 1:

[0059] A method for handling oil pressure sensor malfunctions, comprising the following steps:

[0060] The engine speed is obtained, and the oil pump control percentage is determined based on the relationship between the engine speed and the upper and lower limits of the preset engine dual-mass flywheel resonance speed range (400rpm to 550rpm in this embodiment). The oil pump control percentage ranges from 0% to 100%. A control percentage of 0% indicates no increase in oil pressure, while a control percentage of 100% indicates that the oil pump increases oil pressure at its maximum capacity. The method of setting the oil pump control percentage in this step is based on ensuring that the rate of change of engine speed is not lower than a preset value (-20rpm / s in this embodiment) during engine speed changes.

[0061] The characteristic value of the coolant temperature is obtained based on the target and actual coolant temperature of the engine. The maximum torque optimization coefficient of the engine is obtained based on the pre-calibrated relationship between the coolant temperature and the maximum torque optimization coefficient of the engine. Then, the maximum torque of the engine is reduced based on the maximum torque optimization coefficient of the engine.

[0062] The rate of change of the target engine coolant temperature is limited to a preset value (0.2℃ / 10ms in this embodiment);

[0063] The rate of change of the target VVT phase of the engine is limited to a preset value (0.5° / 10ms).

[0064] Furthermore, when the engine speed is lower than the upper limit of the engine's dual-mass flywheel resonance speed band, the oil pump control percentage (pct) is adjusted. OilPump It is 100%;

[0065] When the engine speed is greater than the upper limit of the engine's dual-mass flywheel resonance speed band, but less than a certain preset value, the oil pump control percentage (pct) is activated. OilPump Represented as,

[0066] pct OilPump =100%×f(n,T) CoolantAct )×f(T Amb ,p Amb )×f(T CoolantStart ,Cnt Com )

[0067] In the above formula, f(n,T) CoolantAct The actual water temperature T of the engine coolant CoolantAct The engine speed n is obtained through calibration; in this embodiment, the calibration is as follows:

[0068]

[0069] The above calibration is based on the fact that the lower the engine speed and the higher the real-time coolant temperature T, the better. CoolantAct The lower the value, the better. CoolantAct The larger the oil pressure, the faster it can rise, improving starting lubrication and allowing the water temperature to rise quickly during starting, resulting in a smoother increase in engine speed.

[0070] f(T Amb ,p Amb (Through atmospheric temperature T) Amb and atmospheric pressure p Amb The calibration was obtained; in this embodiment, the calibration is as follows:

[0071]

[0072] The above calibration is based on the atmospheric temperature T. Amb The lower and atmospheric pressure p Amb The lower the value, the better. Amb ,p Amb The larger the oil pressure, the faster it can rise, improving starting lubrication and achieving a smoother increase in engine speed, especially under conditions of poor combustion and pumping capacity at low temperatures and low pressures.

[0073] f(T CoolantStart ,Cnt Com The temperature T of the coolant during engine start-up CoolantStart (Cooler temperature when the engine is first started) and the number of combustion cycles (Cnt) during engine start-up. Com (The total number of ignitions in each cylinder during engine starting) is calibrated; in this embodiment, the calibration is as follows:

[0074]

[0075] The above calibration is based on the starting cooling water temperature T. CoolantStart The lower the Cnt engine combustion frequency, the better. Com The lower the value, the better. CoolantStart ,Cnt Com The larger the oil pressure, the lower the temperature inside the engine cylinder, and the less stable the combustion conditions are. This allows the oil pressure to rise as quickly as possible, improving starting lubrication and making the engine speed increase smoother.

[0076] When the engine speed exceeds a certain preset value, the oil pump control percentage (pct) is then activated. OilPump Represented as,

[0077]

[0078] In the above formula, the feedforward part Pct FF It is represented as follows,

[0079] Pct FF =[f(n,p OilDesird )+Pct PistonCooling ]×f(T Oil )

[0080] In the above formula, f(n,p) OilDesird During bench calibration, the engine speed n and target oil pressure P are used as the references. OilDesird Calibration yielded; Pct PistonCooling Determined by the activation state of the piston cooling nozzle, f(T) Oil According to the oil temperature T Oil The calibration was obtained;

[0081] In this embodiment, f(T) Oil The calibration is as follows:

[0082]

[0083] f(n diff ,dn diff ) is the speed difference correction factor, which is based on the engine speed difference n diff The rate of change of engine speed difference dn diff The calibration yielded f(n) in this embodiment. diff ,dn diff The calibration is as follows:

[0084]

[0085] The above calibration is based on the principle that if increasing the oil pump control percentage can improve the closed-loop control accuracy of engine speed (i.e., reduce the difference between the target speed and the actual speed), then the oil pressure should be increased; otherwise, the oil pressure should not be increased, i.e., the oil pump control percentage should not be increased.

[0086] Engine speed difference n diff The difference between the target engine speed and the actual engine speed, dn is the rate of change of the engine speed difference. diff For n diff The first derivative; when the engine is not under closed-loop control, f(n) diff ,dn diff The value of ) is 1;

[0087] This is the VVT ​​phase difference correction factor, which is based on the engine speed n and the VVT ​​control characteristic value. Obtained through calibration; in this embodiment The calibration is as follows:

[0088]

[0089] The above calibration is based on the following principle: if increasing the oil pump control percentage can improve the engine VVT ​​control accuracy (i.e., reduce the difference between the target VVT phase and the actual VVT phase), then the oil pump control duty cycle should be increased; otherwise, the oil pump control percentage should not be increased.

[0090] The value is determined by the target VVT phase phi VVTDsrd and actual VVT phase phi VVTAct Decision: When VVT control is not a closed-loop control. The value is 1;

[0091] This is a cooling water temperature difference correction factor, which is based on the characteristic value of the cooling water temperature. Engine speed n is obtained through calibration; Coolant temperature characteristic value The target water temperature T of the engine coolant CoolantDsrd Actual water temperature T CoolantAct Decide;

[0092] In this embodiment The calibration is as follows:

[0093]

[0094] The calibration basis is that if increasing the oil pump control percentage can improve the engine coolant temperature control accuracy (i.e., reduce the difference between the target coolant temperature and the actual coolant temperature), then the oil pump control duty cycle should be increased; otherwise, the oil pump control percentage should not be increased.

[0095] r Adapt r is the self-learning correction coefficient. Adapt It updates through self-learning.

[0096] Furthermore, Pct PistonCooling The specific value selection method is as follows;

[0097] When the piston cooling nozzles are not activated, Pct PistonCooling =C0, where C0 (50% in this embodiment) is a preset percentage;

[0098] When the piston cooling nozzle is activated, Pct PistonCooling (n+1)=Pct PistonCooling (n)+C,Pct PistonCooling (n), Pct PistonCooling (n+1) represent the Pct values ​​of the update cycle for the activation state of the nth and (n+1)th piston cooling nozzles, respectively. PistonCooling The increment C (5% in this embodiment) is a preset percentage, and n = 0, 1, 2....

[0099] Furthermore, if the engine only has intake VVT, then the target VVT phase phi VVTDsrd and actual VVT phase phi VVTAct The input is the intake VVT; if the engine only has an exhaust VVT, then the target VVT phase phi VVTDsrd and actual VVT phase phi VVTAct The input is the exhaust VVT; if the engine has both intake VVT ​​and exhaust VVT, then the target VVT phase phi VVTDsrd and actual VVT phase phi VVTAct The input is the larger of the intake VVT ​​and exhaust VVT.

[0100] Furthermore, when in a self-learning state and meeting the conditions for advanced self-learning, r Adap t performs self-learning updates;

[0101] After entering self-learning update mode, calculate the average engine speed, average engine load, average coolant target temperature, piston cooling nozzle status, average oil temperature, and VVT control characteristic value within a preset time t2 (5 seconds in this embodiment). Average value, characteristic value of cooling water temperature The average value is calculated as follows: if an intake VVT ​​phase exists within time t2, the average value of the intake VVT ​​phase within t2 is calculated; if an exhaust VVT phase exists within t2, the average value of the exhaust VVT phase within t2 is calculated. The average operating condition is defined as follows: if the average engine speed, average engine load, average coolant target temperature, piston cooling nozzle status, average oil temperature, average intake VVT ​​phase, and average exhaust VVT phase are all the same across two time periods t2, then the vehicle is considered to be operating under the same average condition at the two different times. The r values ​​under different average conditions... Adapt Store and update independently;

[0102] r Adapt The update method is as follows:

[0103] If within t2, The average value is less than -0.05, and If the average value is >0.08, then r under this average working condition... Adapt Updated to r Adapt =r Adapt (z)+0.005;r Adapt (z) is the self-learning correction coefficient before the update; since excessive engine coolant temperature may damage the engine, it has a higher priority than VVT response accuracy control, so the absolute value of the design coolant temperature deviation is smaller than that of VVT deviation.

[0104] If within t2, The average value is less than -0.05, and If the average value is >0.03, then r under this average working condition is... Adapt Updated to r Adapt =r Adapt (z)+0.004;

[0105] If within t2, The average value is less than -0.05, and If the average value is >0.01, then r under this average working condition is... Adapt Updated to r Adapt =r Adapt (z)+0.003;

[0106] If within t2, If the average value is ≤ -0.01, then r under this average working condition is... Ad ap tUpdated to r Adapt =r Adapt (z)+0.0025;

[0107] If within t2, The average value is ≤0.01, and If the average value is >0.01, then r under this average working condition is... Adapt Updated to r Adapt =r Adapt (z)+0.002;

[0108] If within t2, The average value is ≤0.01, and If the average value is less than -0.01, then r under this average working condition is... Adapt Updated to r Adapt =r Adapt (z)+0.001;

[0109] If within t2 Average and If the average value does not meet any of the above conditions, then the r value under the average working condition shall be... Adapt Updated to r Adapt =r Adapt (z);

[0110] The self-learning correction coefficient r during each driving cycle Adap t can be updated at most once.

[0111] Furthermore, the self-learning operating condition is defined as follows:

[0112] 1) The engine speed is within the preset range (750rpm-5000rpm in this example), and the engine speed fluctuation after entering the self-learning update is within the preset range (±30rpm in this example);

[0113] 2) The fluctuation of the fresh air intake density entering the cylinder is within the preset range (±15 mgpl in this example);

[0114] 3) The oil temperature fluctuation is within the preset range (±15 mgpl in this example);

[0115] 4) The target temperature fluctuation of the engine coolant is within the preset range (±0.5℃ in this example);

[0116] 5) VVT closed-loop control activated; Specifically, if the engine only has intake VVT, then only the control status of intake VVT ​​is judged; if the engine only has exhaust VVT, then only the control status of exhaust VVT is judged; if the engine has both intake VVT ​​and exhaust VVT, then both intake VVT ​​and exhaust VVT should be in the closed-loop control activated state.

[0117] 6) The target VVT phase fluctuation of the engine is within the preset range (±0.5° in this example); specifically, if the engine only has intake VVT, then only the intake VVT ​​angle is judged; if the engine only has exhaust VVT, then only the exhaust VVT angle is judged; if the engine has both intake VVT ​​and exhaust VVT, then both intake VVT ​​phase fluctuation and exhaust VVT phase fluctuation should be within the preset range.

[0118] 7) The activation state of the piston cooling nozzles remained unchanged;

[0119] 8) No engine knocking occurred;

[0120] 9) No pre-ignition occurred in the engine;

[0121] When all of the above conditions are met, the vehicle is considered to be in self-learning mode.

[0122] Furthermore, the conditions for self-learning advancement are as follows;

[0123] 1) The vehicle is continuously in self-learning mode for no less than a preset time t1 (3s in this embodiment);

[0124] 2) The number of driving cycles without updated self-learning correction coefficients exceeds the preset number (20 times in this embodiment); after the self-learning correction coefficients are updated, the number of driving cycles without updated self-learning correction coefficients is reset to zero;

[0125] When all of the above conditions are met, the vehicle is deemed to meet the self-learning advancement conditions.

[0126] Furthermore, the specific method for reducing the engine's maximum torque is as follows: based on the target coolant temperature T of the engine. CoolantDsrd Actual water temperature T CoolantAct Determine the characteristic value of cooling water temperature Based on cooling water temperature characteristic value Determine the engine maximum torque optimization coefficient k MaxTrq The engine's maximum torque optimization coefficient k MaxTrq The optimized engine maximum torque is obtained by multiplying it by the engine's maximum torque (the method for determining the engine's maximum torque before optimization can be found in existing technology CN202010632793.4 "Method for Determining the Maximum Output Torque of a Gasoline Engine"); where the coolant temperature characteristic value is... With the engine maximum torque optimization coefficient k MaxTrq The relationship is obtained through pre-calibration;

[0127] In this embodiment, the calibration is as follows:

[0128]

[0129] The basis for the above calibration is to reduce the engine's maximum torque in order to avoid abnormal knocking and other phenomena caused by improper oil pressure.

[0130] Furthermore, the preset duration for delaying the opening and closing of the piston cooling nozzle is t3. t3 is based on the maximum value of the ignition angle delay after knocking when the original piston cooling nozzle was open in the previous state of the vehicle (the ignition angle is delayed after knocking to suppress knocking; that is, the maximum value of the ignition angle delay after knocking when the original piston cooling nozzle was open before it was closed), and the octane rating coefficient (the octane rating r of the oil mentioned in patent CN202010608134.7 "A Method and System for Self-Learning Octane Rating of Oil"). OctaneRatio (They are calibrated to have the same physical meaning)

[0131] The calibration process in this embodiment is as follows:

[0132]

[0133] The basis for the above calibration is to avoid exacerbating knocking and damaging the engine.

[0134] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A method for handling oil pressure sensor malfunctions, characterized in that: The method includes the following steps: The engine speed is obtained, and the oil pump control percentage is determined based on the relationship between the engine speed and the upper and lower limits of the preset engine dual-mass flywheel resonance speed band. The oil pump control percentage ranges from 0% to 100%. A control percentage of 0% means no increase in oil pressure, while a control percentage of 100% means the oil pump increases oil pressure at its maximum capacity. The characteristic value of the coolant temperature is obtained based on the target and actual coolant temperature of the engine. The maximum torque optimization coefficient of the engine is obtained based on the pre-calibrated relationship between the coolant temperature and the maximum torque optimization coefficient of the engine. Then, the maximum torque of the engine is reduced based on the maximum torque optimization coefficient of the engine. The rate of change of the target coolant temperature of the engine is limited to not exceed a preset value; The rate of change of the target VVT phase of the engine is limited to not exceed a preset value; If the piston cooling nozzle is currently open, then keep the piston cooling nozzle open; if the piston cooling nozzle is currently closed, then keep the piston cooling nozzle closed; if the piston cooling nozzle is to switch from the open state to the closed state, then delay the switching time by a preset duration.

2. The method for handling oil pressure sensor malfunctions according to claim 1, characterized in that: When the engine speed is lower than the upper limit of the engine's dual-mass flywheel resonance speed band, the oil pump control percentage is adjusted. 100%; When the engine speed is greater than the upper limit of the engine's dual-mass flywheel resonance speed band, but less than a certain preset value, the oil pump control percentage is [not specified]. Represented as, In the above formula, The actual water temperature of the engine coolant And the engine speed n is calibrated; By atmospheric temperature and atmospheric pressure The calibration was obtained; The temperature of the coolant when the engine is started and the number of combustion cycles during engine start-up The calibration was obtained; When the engine speed exceeds a certain preset value, the oil pump control percentage is... Represented as, In the above formula, the feedforward part It is represented as follows, In the above formula, During bench calibration, the engine speed n and target oil pressure are used as the reference. The calibration was obtained; Determined by the activation state of the piston cooling nozzles. According to the oil temperature The calibration was obtained; This is the speed difference correction factor, which is based on the engine speed difference. Rate of change of engine speed difference The engine speed difference was obtained during calibration. The difference between the target engine speed and the actual engine speed, and the rate of change of the engine speed difference. for The first derivative; when the engine is not under closed-loop control. The value is 1; This is the VVT ​​phase difference correction factor, which is based on the engine speed n and the VVT ​​control characteristic value. The calibration was obtained; The value is determined by the target VVT phase. Phase with actual VVT Decision: When VVT control is not a closed-loop control. The value is 1; This is a cooling water temperature difference correction factor, which is based on the characteristic value of the cooling water temperature. The engine speed n is obtained through calibration; Cooling water temperature characteristic value The target water temperature of the engine coolant Actual water temperature Decide; For self-learning correction coefficients, It updates through self-learning.

3. The method for handling oil pressure sensor malfunctions according to claim 2, characterized in that: The specific value selection method is as follows; When the piston cooling nozzles are not activated , This is a preset percentage; When the piston cooling nozzles are activated , , These represent the update cycles of the activation status of the nth and (n+1)th piston cooling nozzles, respectively. The increment C is a preset percentage, and n=0,1,2....

4. The method for handling oil pressure sensor malfunctions according to claim 2, characterized in that: If the engine only has intake VVT, then the target VVT phase Phase with actual VVT The input is the intake VVT; if the engine only has exhaust VVT, then the target VVT phase is... Phase with actual VVT The input is the exhaust VVT; if the engine has both intake VVT ​​and exhaust VVT, then the target VVT phase is... Phase with actual VVT The input is the maximum value of the intake VVT ​​and exhaust VVT.

5. The method for handling oil pressure sensor malfunctions according to claim 2, characterized in that: When in self-learning mode and meeting the conditions for self-learning advancement, Perform self-learning updates; After entering self-learning update mode, calculate the preset time. Average engine speed, average engine load, average target coolant temperature, piston cooling nozzle status, average oil temperature, and VVT control characteristic values. Average value, characteristic value of cooling water temperature Average value, if If the memory is in the intake VVT ​​phase, then calculate The average intake VVT ​​phase value, if If the memory is in the exhaust VVT phase, then calculate... The average value of the exhaust VVT phase; the average operating condition is defined as follows: if the vehicle has two at different times... If the average engine speed, average engine load, average target coolant temperature, average piston cooling nozzle status, average oil temperature, average intake VVT ​​phase, and average exhaust VVT phase are all the same over a given period, then the vehicle is considered to be operating under the same average conditions at the two different times mentioned. Store and update independently; The update method is as follows: like Inside, The average value is less than -0.05, and If the average value is >0.08, then the average value under this working condition is... Updated to ; The self-learning correction coefficients before the update; like Inside, The average value is less than -0.05 and 0.08 is greater than or equal to 0.

08. If the average value is >0.03, then the average value under this working condition is... Updated to ; like Inside, The average value is less than -0.05 and 0.03 is greater than or equal to 0.

03. If the average value is >0.01, then the average value under this working condition is... Updated to ; like Inside, -0.05< If the average value is ≤ -0.01, then the average value under this working condition is... Updated to ; like Inside, -0.01< The average value is ≤0.01, and If the average value is >0.01, then the average value under this working condition is... Updated to ; like Inside, -0.01< The average value is ≤0.01, and If the average value is less than -0.01, then the average value under that working condition is... Updated to ; like Inside Average and If the average value does not meet any of the above conditions, then the average operating condition will be... Updated to .

6. The method for handling oil pressure sensor malfunctions according to claim 5, characterized in that: The self-learning operating condition is defined as follows: 1) The engine speed is within the preset range, and the engine speed fluctuation after entering the self-learning update is within the preset range; 2) The fluctuation in the density of fresh air entering the cylinder is within the preset range; 3) The oil temperature fluctuation is within the preset range; 4) The target temperature fluctuation of the engine coolant is within the preset range; 5) VVT closed-loop control activated; Specifically, if the engine only has intake VVT, then only the control status of intake VVT ​​is judged; if the engine only has exhaust VVT, then only the control status of exhaust VVT is judged; if the engine has both intake VVT ​​and exhaust VVT, then both intake VVT ​​and exhaust VVT should be in the closed-loop control activated state. 6) The target VVT phase fluctuation of the engine is within the preset range; specifically, if the engine only has intake VVT, then only the intake VVT ​​angle is judged; if the engine only has exhaust VVT, then only the exhaust VVT angle is judged; if the engine has both intake VVT ​​and exhaust VVT, then both intake VVT ​​phase fluctuation and exhaust VVT phase fluctuation should be within the preset range. 7) The activation state of the piston cooling nozzles remained unchanged; 8) No engine knocking occurred; 9) No pre-ignition occurred in the engine; When all of the above conditions are met, the vehicle is considered to be in self-learning mode.

7. The method for handling oil pressure sensor malfunctions according to claim 5, characterized in that: The conditions for self-learning advancement are as follows; 1) The vehicle remains in self-learning mode for no less than the preset time. ; 2) The number of driving cycles without updating the self-learning correction coefficient exceeds the preset number; When all of the above conditions are met, the vehicle is deemed to meet the self-learning advancement conditions.

8. The method for handling oil pressure sensor malfunctions according to claim 1, characterized in that: The specific method to reduce the engine's maximum torque is based on the target engine coolant temperature. Actual water temperature Determine the characteristic value of cooling water temperature Based on the characteristic value of cooling water temperature Determine the engine maximum torque optimization coefficient Optimize the engine's maximum torque coefficient The optimized maximum engine torque is obtained by multiplying the maximum torque by the engine's maximum torque; where the coolant temperature characteristic value is... With engine maximum torque optimization coefficient The relationship is obtained through pre-calibration.

9. The method for handling oil pressure sensor malfunctions according to claim 1, characterized in that: The preset duration for delaying the opening and closing of the piston cooling nozzle is: , The value of the delayed ignition angle after knocking when the original piston cooling nozzles were opened in the previous state of the vehicle was obtained from the calibration of the octane number coefficient.

10. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, it implements the steps of the oil pressure sensor failure post-processing method according to any one of claims 1-9.

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