Automobile engine oil pressure control method and system

Abstract

The application discloses a kind of automobile engine oil pressure control method and system, the method includes: the original actual oil pressure of engine is collected, and filtering processing is carried out, and the actual oil pressure after filtering is obtained;The state of current VVT is obtained, when the state of VVT is in closed loop activation state, set oil pressure switching condition, when the oil pressure switching condition is satisfied, the actual oil pressure after filtering is used as the actual oil pressure of oil pressure closed loop control, otherwise, the original actual oil pressure is used as the actual oil pressure of oil pressure closed loop control;The original target oil pressure is obtained, the oil pressure dynamic control mode is set, and according to the actual oil pressure, the final target oil pressure of automobile is controlled.

Description

Technical Field

[0001] This invention belongs to the field of automotive oil pressure control technology, and more specifically, relates to an automotive oil pressure control method and system. 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, an engine should ideally operate at its optimal temperature, thus requiring a suitable cooling system. The setting of the target oil pressure is crucial for engine power, economy, and engine lifespan. However, significant variations in the target oil pressure can lead to issues such as low closed-loop control accuracy and poor robustness.

[0003] CN202010523747.0, "A Control Method and System for a Variable Displacement Oil Pump for Vehicles," describes a control method for a variable displacement oil pump for vehicles. This method primarily determines the deviation influence factor, overshoot influence factor, and steady-state influence factor based on the difference between the target oil pressure and the actual oil pressure. It calculates the P-term control percentage and D-term control percentage; calculates the I-term control percentage based on the feedforward control duty cycle, the P-term control percentage, the D-term control percentage, and the I-term control percentage from the previous moment; and uses the sum of the feedforward control duty cycle, the P-term control percentage, the D-term control percentage, and the I-term control percentage as the oil pump duty cycle. Target oil pressures are set for different operating conditions, and the responsiveness and accuracy of the oil pressure closed-loop control are improved through a "feedforward + PID" control method. This patent mainly focuses on setting target oil pressures for different operating conditions and improving the responsiveness and accuracy of the oil pressure closed-loop control through a "feedforward + PID" control method. This patent sets the oil pressure control to multiple control modes, including rapid oil pressure build-up mode, precise oil pressure control mode, normal control mode, and performance-limited control mode. In each mode, corresponding conditions are determined. When the conditions are met, the closed-loop PI control parameter I is allowed to learn between the target oil pressure and the actual oil pressure. This patent can control the engine oil pressure more intelligently, which not only protects the engine but also achieves rapid oil pressure build-up, improving control accuracy and engine life.

[0004] CN202010829619.9, "Method for Controlling an Oil Pump in a Vehicle," utilizes detected information about the engine's operating status or driving conditions. A controller, based on this information, determines whether predetermined conditions for an alternating mode are met. When these conditions are met, the controller sequentially executes high-pressure operation control and low-pressure operation control. The high-pressure operation control regulates the operation of the oil pump system, thereby bringing the engine oil pressure closer to a predetermined target high-pressure value. The low-pressure operation control regulates the engine oil pressure, bringing it closer to a predetermined target low-pressure value. This patent primarily employs an alternating mode to execute high-pressure and low-pressure operation control, thereby bringing the oil pressure closer to predetermined target high-pressure and low-pressure values. This patent, however, eliminates the need for alternating mode control and performs closed-loop PI control of the target and actual existing pressures under multiple custom control modes. This patent provides a more intelligent way to control engine oil pressure, protecting the engine while achieving rapid oil pressure build-up, improving control accuracy and engine lifespan. Summary of the Invention

[0005] To solve the above technical problems, this invention proposes a method for controlling automotive oil pressure, comprising:

[0006] The engine's original actual oil pressure is collected and filtered to obtain the filtered actual oil pressure.

[0007] Obtain the current VVT state. When the VVT ​​state is in the closed-loop active state, set the oil pressure switching condition. When the oil pressure switching condition is met, use the filtered actual oil pressure as the actual oil pressure for oil pressure closed-loop control. Otherwise, use the original actual oil pressure as the actual oil pressure for oil pressure closed-loop control.

[0008] Obtain the original target oil pressure, set the oil pressure dynamic control mode, and control the final target oil pressure of the vehicle according to the actual oil pressure.

[0009] Furthermore, the current state of VVT includes:

[0010] When VVT is in a non-closed-loop control state;

[0011] When the VVT ​​is in closed-loop active state and the actual VVT position is not close to the locking position;

[0012] When the VVT ​​is in the closed-loop active state and the actual VVT position is close to the locked position.

[0013] Furthermore, the conditions for setting the hydraulic pressure switching include:

[0014] The difference between the filtered actual oil pressure and the original actual oil pressure is greater than a preset difference.

[0015] The difference between the original target oil pressure and the filtered actual oil pressure does not exceed a preset range;

[0016] The original target oil pressure fluctuation range does not exceed the preset fluctuation range, and the duration exceeds T0.

[0017] Furthermore, the hydraulic dynamic control modes include:

[0018] In Mode 1, if the difference between the original target oil pressure and the actual oil pressure exceeds a preset value p1, and the rate of change of the actual oil pressure is lower than a preset value dPa, then the final target oil pressure is set to the original target oil pressure, and the oil pump is controlled in open-loop mode with maximum displacement, and the maintenance time is not less than T1.

[0019] In Mode 2, if the difference between the original target oil pressure and the actual oil pressure exceeds a preset value p1, and the rate of change of the actual oil pressure is not lower than a preset value dPa, then the final target oil pressure is set to the original target oil pressure minus a preset value C1 as the final target oil pressure, and the oil pump is controlled by a combination of feedforward and PID control, and the maintenance time is not less than T2.

[0020] In mode 3, if the difference between the original target oil pressure and the actual oil pressure does not exceed a preset value p1 but exceeds p2, and the rate of change of the actual oil pressure is lower than a preset value dPa, then the final target oil pressure is set to the original target oil pressure minus a preset value C2, where C2 < C1, and the oil pump is controlled by adjusting the P and I terms in the PID controller.

[0021] Mode 4: If the difference between the original target oil pressure and the actual oil pressure does not exceed a preset value p1 but exceeds p2, and the rate of change of the actual oil pressure is not lower than a preset value dPa, then the final target oil pressure is set to the original target oil pressure, and the oil pump control is performed using a feedforward combined with PID control.

[0022] The priority of modes 1 through 4 decreases progressively.

[0023] Furthermore, it also includes self-learning updates of preset values ​​C1 and C2, and durations T1 and T2, specifically:

[0024] If the oil pressure fluctuation exceeds ±5 kPa in Mode 1, the preset value C1 will be updated to 0.98 ± 0.1 times the previous value in the next driving cycle; if the oil pressure fluctuation does not exceed ±5 kPa for any of the CNT consecutive driving cycles, the preset value C1 will be updated to 1.02 ± 0.1 times the previous value in the next driving cycle; otherwise, the preset value C1 will remain unchanged from the previous value.

[0025] If the oil pressure fluctuation exceeds ±5 kPa within the preset time t1 after exiting mode 1, the maintenance time T1 of the next driving cycle will be updated to 1.02 ± 0.1 times the previous update value; if the oil pressure fluctuation does not exceed ±5 kPa for any of the consecutive CNT cycles, the maintenance time T1 of the next driving cycle will be updated to 0.98 ± 0.1 times the previous update value; otherwise, the maintenance time T1 will remain unchanged from the previous update value.

[0026] If the oil pressure fluctuation exceeds ±5 kPa in Mode 2, the preset value C2 will be updated to 0.95 ± 0.1 times the previous value in the next driving cycle; if the oil pressure fluctuation does not exceed ±5 kPa for any of the next CNT cycles, the preset value C2 will be updated to 1.05 ± 0.1 times the previous value in the next driving cycle; otherwise, the preset value C2 will remain unchanged from the previous value.

[0027] If the oil pressure fluctuation exceeds ±5 kPa within the preset time t1 after exiting mode 2, the maintenance time T2 of the next driving cycle will be updated to 1.01 ± 0.1 times the previous update value; if the oil pressure fluctuation does not exceed ±5 kPa for any of the consecutive CNT cycles, the maintenance time T2 of the next driving cycle will be updated to 0.99 ± 0.1 times the previous update value; otherwise, the maintenance time T2 will remain unchanged from the previous update value.

[0028] This invention also proposes an automotive oil pressure control system, comprising:

[0029] The data acquisition module is used to collect the engine's original actual oil pressure, perform filtering processing, and obtain the filtered actual oil pressure.

[0030] The hydraulic pressure switching module is used to obtain the current VVT status. When the VVT ​​status is in the closed-loop active state, the hydraulic pressure switching conditions are set. When the hydraulic pressure switching conditions are met, the filtered actual hydraulic pressure is used as the actual hydraulic pressure for hydraulic pressure closed-loop control. Otherwise, the original actual hydraulic pressure is used as the actual hydraulic pressure for hydraulic pressure closed-loop control.

[0031] The control module is used to acquire the original target oil pressure, set the oil pressure dynamic control mode, and control the final target oil pressure of the vehicle according to the actual oil pressure.

[0032] Furthermore, the current state of VVT includes:

[0033] When VVT is in a non-closed-loop control state;

[0034] When the VVT ​​is in closed-loop active state and the actual VVT position is not close to the locking position;

[0035] When the VVT ​​is in the closed-loop active state and the actual VVT position is close to the locked position.

[0036] Furthermore, the conditions for setting the hydraulic pressure switching include:

[0037] The difference between the filtered actual oil pressure and the original actual oil pressure is greater than a preset difference.

[0038] The difference between the original target oil pressure and the filtered actual oil pressure does not exceed a preset range;

[0039] The original target oil pressure fluctuation range does not exceed the preset fluctuation range, and the duration exceeds T0.

[0040] Furthermore, the hydraulic dynamic control modes include:

[0041] In Mode 1, if the difference between the original target oil pressure and the actual oil pressure exceeds a preset value p1, and the rate of change of the actual oil pressure is lower than a preset value dPa, then the final target oil pressure is set to the original target oil pressure, and the oil pump is controlled in open-loop mode with maximum displacement, and the maintenance time is not less than T1.

[0042] In Mode 2, if the difference between the original target oil pressure and the actual oil pressure exceeds a preset value p1, and the rate of change of the actual oil pressure is not lower than a preset value dPa, then the final target oil pressure is set to the original target oil pressure minus a preset value C1 as the final target oil pressure, and the oil pump is controlled by a combination of feedforward and PID control, and the maintenance time is not less than T2.

[0043] In mode 3, if the difference between the original target oil pressure and the actual oil pressure does not exceed a preset value p1 but exceeds p2, and the rate of change of the actual oil pressure is lower than a preset value dPa, then the final target oil pressure is set to the original target oil pressure minus a preset value C2, where C2 < C1, and the oil pump is controlled by adjusting the P and I terms in the PID controller.

[0044] Mode 4: If the difference between the original target oil pressure and the actual oil pressure does not exceed a preset value p1 but exceeds p2, and the rate of change of the actual oil pressure is not lower than a preset value dPa, then the final target oil pressure is set to the original target oil pressure, and the oil pump control is performed using a feedforward combined with PID control.

[0045] The priority of modes 1 through 4 decreases progressively.

[0046] Furthermore, it also includes self-learning updates of preset values ​​C1 and C2, and durations T1 and T2, specifically:

[0047] If the oil pressure fluctuation exceeds ±5 kPa in Mode 1, the preset value C1 will be updated to 0.98 ± 0.1 times the previous value in the next driving cycle; if the oil pressure fluctuation does not exceed ±5 kPa for any of the CNT consecutive driving cycles, the preset value C1 will be updated to 1.02 ± 0.1 times the previous value in the next driving cycle; otherwise, the preset value C1 will remain unchanged from the previous value.

[0048] If the oil pressure fluctuation exceeds ±5 kPa within the preset time t1 after exiting mode 1, the maintenance time T1 of the next driving cycle will be updated to 1.02 ± 0.1 times the previous update value; if the oil pressure fluctuation does not exceed ±5 kPa for any of the consecutive CNT cycles, the maintenance time T1 of the next driving cycle will be updated to 0.98 ± 0.1 times the previous update value; otherwise, the maintenance time T1 will remain unchanged from the previous update value.

[0049] If the oil pressure fluctuation exceeds ±5 kPa in Mode 2, the preset value C2 will be updated to 0.95 ± 0.1 times the previous value in the next driving cycle; if the oil pressure fluctuation does not exceed ±5 kPa for any of the next CNT cycles, the preset value C2 will be updated to 1.05 ± 0.1 times the previous value in the next driving cycle; otherwise, the preset value C2 will remain unchanged from the previous value.

[0050] If the oil pressure fluctuation exceeds ±5 kPa within the preset time t1 after exiting mode 2, the maintenance time T2 of the next driving cycle will be updated to 1.01 ± 0.1 times the previous update value; if the oil pressure fluctuation does not exceed ±5 kPa for any of the consecutive CNT cycles, the maintenance time T2 of the next driving cycle will be updated to 0.99 ± 0.1 times the previous update value; otherwise, the maintenance time T2 will remain unchanged from the previous update value.

[0051] In summary, the technical solutions conceived by this invention have the following beneficial effects compared with the prior art:

[0052] This invention provides a target oil pressure control method from the perspectives of engine protection, fuel economy, and improved control precision, solving the problems of low closed-loop control precision and poor robustness when the target oil pressure changes significantly. Attached Figure Description

[0053] Figure 1 This is a flowchart of the method of Embodiment 1 of the present invention;

[0054] Figure 2 This is a structural diagram of the system in Embodiment 2 of the present invention. Detailed Implementation

[0055] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0056] The method provided by this invention can be implemented in a terminal environment that may include one or more of the following components: a processor, a storage medium, and a display screen. The storage medium stores at least one instruction, which is loaded and executed by the processor to implement the method described in the following embodiments.

[0057] A processor may include one or more processing cores. The processor uses various interfaces and lines to connect various parts of the terminal, and performs various functions and processes data by running or executing instructions, programs, code sets or instruction sets stored in the storage medium, and by calling data stored in the storage medium.

[0058] Storage media can include random access memory (RAM) or read-only memory (ROM). Storage media can be used to store instructions, programs, code, code sets, or instructions.

[0059] The display screen is used to show the user interface of each application.

[0060] In the formula of this invention, all subscripts are only used to distinguish parameters and have no actual meaning.

[0061] In addition, those skilled in the art will understand that the structure of the terminal described above does not constitute a limitation on the terminal. The terminal may include more or fewer components, or combine certain components, or have different component arrangements. For example, the terminal may also include radio frequency circuits, input units, sensors, audio circuits, power supplies, and other components, which will not be described in detail here.

[0062] Example 1

[0063] like Figure 1 As shown, an embodiment of the present invention provides a method for controlling automotive oil pressure, comprising:

[0064] Step 101: Collect the original actual oil pressure of the engine and perform filtering to obtain the filtered actual oil pressure;

[0065] Step 102: Obtain the current VVT state. When the VVT ​​state is in the closed-loop active state, set the oil pressure switching condition. When the oil pressure switching condition is met, use the filtered actual oil pressure as the actual oil pressure for oil pressure closed-loop control. Otherwise, use the original actual oil pressure as the actual oil pressure for oil pressure closed-loop control.

[0066] Specifically, the current state of VVT includes:

[0067] When VVT is in a non-closed-loop control state;

[0068] When the VVT ​​is in closed-loop active state and the actual VVT position is not close to the locking position;

[0069] When the VVT ​​is in the closed-loop active state and the actual VVT position is close to the locked position.

[0070] Specifically, the conditions for setting the hydraulic pressure switching include:

[0071] The difference between the filtered actual oil pressure and the original actual oil pressure is greater than a preset difference.

[0072] The difference between the original target oil pressure and the filtered actual oil pressure does not exceed a preset range;

[0073] The original target oil pressure fluctuation range does not exceed the preset fluctuation range, and the duration exceeds T0.

[0074] Step 103: Obtain the original target oil pressure, set the oil pressure dynamic control mode, and control the final target oil pressure of the vehicle according to the actual oil pressure.

[0075] Specifically, the hydraulic dynamic control modes include:

[0076] In Mode 1, if the difference between the original target oil pressure and the actual oil pressure exceeds a preset value p1, and the rate of change of the actual oil pressure is lower than a preset value dPa, then the final target oil pressure is set to the original target oil pressure, and the oil pump is controlled in open-loop mode with maximum displacement, and the maintenance time is not less than T1.

[0077] In Mode 2, if the difference between the original target oil pressure and the actual oil pressure exceeds a preset value p1, and the rate of change of the actual oil pressure is not lower than a preset value dPa, then the final target oil pressure is set to the original target oil pressure minus a preset value C1 as the final target oil pressure, and the oil pump is controlled by a combination of feedforward and PID control, and the maintenance time is not less than T2.

[0078] In mode 3, if the difference between the original target oil pressure and the actual oil pressure does not exceed a preset value p1 but exceeds p2, and the rate of change of the actual oil pressure is lower than a preset value dPa, then the final target oil pressure is set to the original target oil pressure minus a preset value C2, where C2 < C1, and the oil pump is controlled by adjusting the P and I terms in the PID controller.

[0079] In Mode 4, if the difference between the original target oil pressure and the actual oil pressure does not exceed a preset value p1 but exceeds p2, and the rate of change of the actual oil pressure is not lower than a preset value dPa, then the final target oil pressure is set to the original target oil pressure, and the oil pump control is performed using a feedforward combined with PID control.

[0080] The priority of modes 1 to 4 decreases progressively. A mode with a lower priority will only be used if the conditions of the previous priority mode are not met.

[0081] Specifically, this also includes self-learning updates of preset values ​​C1 and C2, and durations T1 and T2, as follows:

[0082] If the oil pressure fluctuation exceeds ±5 kPa in Mode 1, the preset value C1 will be updated to 0.98 ± 0.1 times the previous value in the next driving cycle; if the oil pressure fluctuation does not exceed ±5 kPa for any of the CNT consecutive driving cycles, the preset value C1 will be updated to 1.02 ± 0.1 times the previous value in the next driving cycle; otherwise, the preset value C1 will remain unchanged from the previous value.

[0083] If the oil pressure fluctuation exceeds ±5 kPa within the preset time t1 after exiting mode 1, the maintenance time T1 of the next driving cycle will be updated to 1.02 ± 0.1 times the previous update value; if the oil pressure fluctuation does not exceed ±5 kPa for any of the consecutive CNT cycles, the maintenance time T1 of the next driving cycle will be updated to 0.98 ± 0.1 times the previous update value; otherwise, the maintenance time T1 will remain unchanged from the previous update value.

[0084] If the oil pressure fluctuation exceeds ±5 kPa in Mode 2, the preset value C2 will be updated to 0.95 ± 0.1 times the previous value in the next driving cycle; if the oil pressure fluctuation does not exceed ±5 kPa for any of the next CNT cycles, the preset value C2 will be updated to 1.05 ± 0.1 times the previous value in the next driving cycle; otherwise, the preset value C2 will remain unchanged from the previous value.

[0085] If the oil pressure fluctuation exceeds ±5 kPa within the preset time t1 after exiting mode 2, the maintenance time T2 of the next driving cycle will be updated to 1.01 ± 0.1 times the previous update value; if the oil pressure fluctuation does not exceed ±5 kPa for any of the consecutive CNT cycles, the maintenance time T2 of the next driving cycle will be updated to 0.99 ± 0.1 times the previous update value; otherwise, the maintenance time T2 will remain unchanged from the previous update value.

[0086] Example 2

[0087] like Figure 2 As shown, this embodiment of the invention also provides an automotive oil pressure control system, comprising:

[0088] The data acquisition module is used to collect the engine's original actual oil pressure, perform filtering processing, and obtain the filtered actual oil pressure.

[0089] The hydraulic pressure switching module is used to obtain the current VVT status. When the VVT ​​status is in the closed-loop active state, the hydraulic pressure switching conditions are set. When the hydraulic pressure switching conditions are met, the filtered actual hydraulic pressure is used as the actual hydraulic pressure for hydraulic pressure closed-loop control. Otherwise, the original actual hydraulic pressure is used as the actual hydraulic pressure for hydraulic pressure closed-loop control.

[0090] Specifically, the current state of VVT includes:

[0091] When VVT is in a non-closed-loop control state;

[0092] When the VVT ​​is in closed-loop active state and the actual VVT position is not close to the locking position;

[0093] When the VVT ​​is in the closed-loop active state and the actual VVT position is close to the locked position.

[0094] Specifically, the conditions for setting the hydraulic pressure switching include:

[0095] The difference between the filtered actual oil pressure and the original actual oil pressure is greater than a preset difference.

[0096] The difference between the original target oil pressure and the filtered actual oil pressure does not exceed a preset range;

[0097] The original target oil pressure fluctuation range does not exceed the preset fluctuation range, and the duration exceeds T0.

[0098] The control module is used to acquire the original target oil pressure, set the oil pressure dynamic control mode, and control the final target oil pressure of the vehicle according to the actual oil pressure.

[0099] Specifically, the hydraulic dynamic control modes include:

[0100] In Mode 1, if the difference between the original target oil pressure and the actual oil pressure exceeds a preset value p1, and the rate of change of the actual oil pressure is lower than a preset value dPa, then the final target oil pressure is set to the original target oil pressure, and the oil pump is controlled in open-loop mode with maximum displacement, and the maintenance time is not less than T1.

[0101] In Mode 2, if the difference between the original target oil pressure and the actual oil pressure exceeds a preset value p1, and the rate of change of the actual oil pressure is not lower than a preset value dPa, then the final target oil pressure is set to the original target oil pressure minus a preset value C1 as the final target oil pressure, and the oil pump is controlled by a combination of feedforward and PID control, and the maintenance time is not less than T2.

[0102] In mode 3, if the difference between the original target oil pressure and the actual oil pressure does not exceed a preset value p1 but exceeds p2, and the rate of change of the actual oil pressure is lower than a preset value dPa, then the final target oil pressure is set to the original target oil pressure minus a preset value C2, where C2 < C1, and the oil pump is controlled by adjusting the P and I terms in the PID controller.

[0103] In Mode 4, if the difference between the original target oil pressure and the actual oil pressure does not exceed a preset value p1 but exceeds p2, and the rate of change of the actual oil pressure is not lower than a preset value dPa, then the final target oil pressure is set to the original target oil pressure, and the oil pump control is performed using a feedforward combined with PID control.

[0104] Specifically, this also includes self-learning updates of preset values ​​C1 and C2, and durations T1 and T2, as follows:

[0105] If the oil pressure fluctuation exceeds ±5 kPa in Mode 1, the preset value C1 will be updated to 0.98 ± 0.1 times the previous value in the next driving cycle; if the oil pressure fluctuation does not exceed ±5 kPa for any of the CNT consecutive driving cycles, the preset value C1 will be updated to 1.02 ± 0.1 times the previous value in the next driving cycle; otherwise, the preset value C1 will remain unchanged from the previous value.

[0106] If the oil pressure fluctuation exceeds ±5 kPa within the preset time t1 after exiting mode 1, the maintenance time T1 of the next driving cycle will be updated to 1.02 ± 0.1 times the previous update value; if the oil pressure fluctuation does not exceed ±5 kPa for any of the consecutive CNT cycles, the maintenance time T1 of the next driving cycle will be updated to 0.98 ± 0.1 times the previous update value; otherwise, the maintenance time T1 will remain unchanged from the previous update value.

[0107] If the oil pressure fluctuation exceeds ±5 kPa in Mode 2, the preset value C2 will be updated to 0.95 ± 0.1 times the previous value in the next driving cycle; if the oil pressure fluctuation does not exceed ±5 kPa for any of the next CNT cycles, the preset value C2 will be updated to 1.05 ± 0.1 times the previous value in the next driving cycle; otherwise, the preset value C2 will remain unchanged from the previous value.

[0108] If the oil pressure fluctuation exceeds ±5 kPa within the preset time t1 after exiting mode 2, the maintenance time T2 of the next driving cycle will be updated to 1.01 ± 0.1 times the previous update value; if the oil pressure fluctuation does not exceed ±5 kPa for any of the consecutive CNT cycles, the maintenance time T2 of the next driving cycle will be updated to 0.99 ± 0.1 times the previous update value; otherwise, the maintenance time T2 will remain unchanged from the previous update value.

[0109] Example 3

[0110] This invention also proposes a storage medium storing multiple instructions for implementing the aforementioned automotive oil pressure control method.

[0111] Optionally, in this embodiment, the storage medium may be located in any computer terminal in a group of computer terminals in a computer network, or in any mobile terminal in a group of mobile terminals.

[0112] Optionally, in this embodiment, the storage medium is configured to store program code for performing the following steps: Step 101, collect the original actual oil pressure of the engine, perform filtering processing, and obtain the filtered actual oil pressure;

[0113] Step 102: Obtain the current VVT state. When the VVT ​​state is in the closed-loop active state, set the oil pressure switching condition. When the oil pressure switching condition is met, use the filtered actual oil pressure as the actual oil pressure for oil pressure closed-loop control. Otherwise, use the original actual oil pressure as the actual oil pressure for oil pressure closed-loop control.

[0114] Specifically, the current state of VVT includes:

[0115] When VVT is in a non-closed-loop control state;

[0116] When the VVT ​​is in closed-loop active state and the actual VVT position is not close to the locking position;

[0117] When the VVT ​​is in the closed-loop active state and the actual VVT position is close to the locked position.

[0118] Specifically, the conditions for setting the hydraulic pressure switching include:

[0119] The difference between the filtered actual oil pressure and the original actual oil pressure is greater than a preset difference.

[0120] The difference between the original target oil pressure and the filtered actual oil pressure does not exceed a preset range;

[0121] The original target oil pressure fluctuation range does not exceed the preset fluctuation range, and the duration exceeds T0.

[0122] Step 103: Obtain the original target oil pressure, set the oil pressure dynamic control mode, and control the final target oil pressure of the vehicle according to the actual oil pressure.

[0123] Specifically, the hydraulic dynamic control modes include:

[0124] In Mode 1, if the difference between the original target oil pressure and the actual oil pressure exceeds a preset value p1, and the rate of change of the actual oil pressure is lower than a preset value dPa, then the final target oil pressure is set to the original target oil pressure, and the oil pump is controlled in open-loop mode with maximum displacement, and the maintenance time is not less than T1.

[0125] In Mode 2, if the difference between the original target oil pressure and the actual oil pressure exceeds a preset value p1, and the rate of change of the actual oil pressure is not lower than a preset value dPa, then the final target oil pressure is set to the original target oil pressure minus a preset value C1 as the final target oil pressure, and the oil pump is controlled by a combination of feedforward and PID control, and the maintenance time is not less than T2.

[0126] In mode 3, if the difference between the original target oil pressure and the actual oil pressure does not exceed a preset value p1 but exceeds p2, and the rate of change of the actual oil pressure is lower than a preset value dPa, then the final target oil pressure is set to the original target oil pressure minus a preset value C2, where C2 < C1, and the oil pump is controlled by adjusting the P and I terms in the PID controller.

[0127] In Mode 4, if the difference between the original target oil pressure and the actual oil pressure does not exceed a preset value p1 but exceeds p2, and the rate of change of the actual oil pressure is not lower than a preset value dPa, then the final target oil pressure is set to the original target oil pressure, and the oil pump control is performed using a feedforward combined with PID control.

[0128] Specifically, this also includes self-learning updates of preset values ​​C1 and C2, and durations T1 and T2, as follows:

[0129] If the oil pressure fluctuation exceeds ±5 kPa in Mode 1, the preset value C1 will be updated to 0.98 ± 0.1 times the previous value in the next driving cycle; if the oil pressure fluctuation does not exceed ±5 kPa for any of the CNT consecutive driving cycles, the preset value C1 will be updated to 1.02 ± 0.1 times the previous value in the next driving cycle; otherwise, the preset value C1 will remain unchanged from the previous value.

[0130] If the oil pressure fluctuation exceeds ±5 kPa within the preset time t1 after exiting mode 1, the maintenance time T1 of the next driving cycle will be updated to 1.02 ± 0.1 times the previous update value; if the oil pressure fluctuation does not exceed ±5 kPa for any of the consecutive CNT cycles, the maintenance time T1 of the next driving cycle will be updated to 0.98 ± 0.1 times the previous update value; otherwise, the maintenance time T1 will remain unchanged from the previous update value.

[0131] If the oil pressure fluctuation exceeds ±5 kPa in Mode 2, the preset value C2 will be updated to 0.95 ± 0.1 times the previous value in the next driving cycle; if the oil pressure fluctuation does not exceed ±5 kPa for any of the next CNT cycles, the preset value C2 will be updated to 1.05 ± 0.1 times the previous value in the next driving cycle; otherwise, the preset value C2 will remain unchanged from the previous value.

[0132] If the oil pressure fluctuation exceeds ±5 kPa within the preset time t1 after exiting mode 2, the maintenance time T2 of the next driving cycle will be updated to 1.01 ± 0.1 times the previous update value; if the oil pressure fluctuation does not exceed ±5 kPa for any of the consecutive CNT cycles, the maintenance time T2 of the next driving cycle will be updated to 0.99 ± 0.1 times the previous update value; otherwise, the maintenance time T2 will remain unchanged from the previous update value.

[0133] Example 4

[0134] This invention also proposes an electronic device, including a processor and a storage medium connected to the processor. The storage medium stores multiple instructions, which can be loaded and executed by the processor to enable the processor to perform the aforementioned automotive oil pressure control method.

[0135] Specifically, the electronic device in this embodiment can be a computer terminal, which may include one or more processors and a storage medium.

[0136] The storage medium can be used to store software programs and modules, such as the automotive oil pressure control method in this embodiment of the invention. The corresponding program instructions / modules are executed by the processor through running the software programs and modules stored in the storage medium, thereby performing various functional applications and data processing, thus realizing the aforementioned automotive oil pressure control method. The storage medium may include high-speed random access storage media, and may also include non-volatile storage media, such as one or more magnetic storage systems, flash memory, or other non-volatile solid-state storage media. In some instances, the storage medium may further include storage media remotely located relative to the processor, which can be connected to the terminal via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0137] The processor can call the information and application stored in the storage medium through the transmission system to perform the following steps: Step 101, collect the original actual oil pressure of the engine, perform filtering processing, and obtain the filtered actual oil pressure;

[0138] Step 102: Obtain the current VVT state. When the VVT ​​state is in the closed-loop active state, set the oil pressure switching condition. When the oil pressure switching condition is met, use the filtered actual oil pressure as the actual oil pressure for oil pressure closed-loop control. Otherwise, use the original actual oil pressure as the actual oil pressure for oil pressure closed-loop control.

[0139] Specifically, the current state of VVT includes:

[0140] When VVT is in a non-closed-loop control state;

[0141] When the VVT ​​is in closed-loop active state and the actual VVT position is not close to the locking position;

[0142] When the VVT ​​is in the closed-loop active state and the actual VVT position is close to the locked position.

[0143] Specifically, the conditions for setting the hydraulic pressure switching include:

[0144] The difference between the filtered actual oil pressure and the original actual oil pressure is greater than a preset difference.

[0145] The difference between the original target oil pressure and the filtered actual oil pressure does not exceed a preset range;

[0146] The original target oil pressure fluctuation range does not exceed the preset fluctuation range, and the duration exceeds T0.

[0147] Step 103: Obtain the original target oil pressure, set the oil pressure dynamic control mode, and control the final target oil pressure of the vehicle according to the actual oil pressure.

[0148] Specifically, the hydraulic dynamic control modes include:

[0149] In Mode 1, if the difference between the original target oil pressure and the actual oil pressure exceeds a preset value p1, and the rate of change of the actual oil pressure is lower than a preset value dPa, then the final target oil pressure is set to the original target oil pressure, and the oil pump is controlled in open-loop mode with maximum displacement, and the maintenance time is not less than T1.

[0150] In Mode 2, if the difference between the original target oil pressure and the actual oil pressure exceeds a preset value p1, and the rate of change of the actual oil pressure is not lower than a preset value dPa, then the final target oil pressure is set to the original target oil pressure minus a preset value C1 as the final target oil pressure, and the oil pump is controlled by a combination of feedforward and PID control, and the maintenance time is not less than T2.

[0151] In mode 3, if the difference between the original target oil pressure and the actual oil pressure does not exceed a preset value p1 but exceeds p2, and the rate of change of the actual oil pressure is lower than a preset value dPa, then the final target oil pressure is set to the original target oil pressure minus a preset value C2, where C2 < C1, and the oil pump is controlled by adjusting the P and I terms in the PID controller.

[0152] In Mode 4, if the difference between the original target oil pressure and the actual oil pressure does not exceed a preset value p1 but exceeds p2, and the rate of change of the actual oil pressure is not lower than a preset value dPa, then the final target oil pressure is set to the original target oil pressure, and the oil pump control is performed using a feedforward combined with PID control.

[0153] Specifically, this also includes self-learning updates of preset values ​​C1 and C2, and durations T1 and T2, as follows:

[0154] If the oil pressure fluctuation exceeds ±5 kPa in Mode 1, the preset value C1 will be updated to 0.98 ± 0.1 times the previous value in the next driving cycle; if the oil pressure fluctuation does not exceed ±5 kPa for any of the CNT consecutive driving cycles, the preset value C1 will be updated to 1.02 ± 0.1 times the previous value in the next driving cycle; otherwise, the preset value C1 will remain unchanged from the previous value.

[0155] If the oil pressure fluctuation exceeds ±5 kPa within the preset time t1 after exiting mode 1, the maintenance time T1 of the next driving cycle will be updated to 1.02 ± 0.1 times the previous update value; if the oil pressure fluctuation does not exceed ±5 kPa for any of the consecutive CNT cycles, the maintenance time T1 of the next driving cycle will be updated to 0.98 ± 0.1 times the previous update value; otherwise, the maintenance time T1 will remain unchanged from the previous update value.

[0156] If the oil pressure fluctuation exceeds ±5 kPa in Mode 2, the preset value C2 will be updated to 0.95 ± 0.1 times the previous value in the next driving cycle; if the oil pressure fluctuation does not exceed ±5 kPa for any of the next CNT cycles, the preset value C2 will be updated to 1.05 ± 0.1 times the previous value in the next driving cycle; otherwise, the preset value C2 will remain unchanged from the previous value.

[0157] If the oil pressure fluctuation exceeds ±5 kPa within the preset time t1 after exiting mode 2, the maintenance time T2 of the next driving cycle will be updated to 1.01 ± 0.1 times the previous update value; if the oil pressure fluctuation does not exceed ±5 kPa for any of the consecutive CNT cycles, the maintenance time T2 of the next driving cycle will be updated to 0.99 ± 0.1 times the previous update value; otherwise, the maintenance time T2 will remain unchanged from the previous update value.

[0158] Example 5

[0159] The purpose of this invention is to address the issue of control accuracy in the closed-loop control of oil pressure when the target oil pressure changes too rapidly during actual development. Oil pressure control is achieved through the oil pump, specifically by controlling the PWM duty cycle of the oil pump.

[0160] First, the actual oil pressure read by the sensor is processed by a first-order low-pass filter:

[0161] p OilAct (N)=k×[p OilActRaw (N)-p OilAct [(N-1)]+p OilAct (N-1), where N = 1, 2, 3, ..., p OilAct (N-1) represents the filtered actual oil pressure at time N-1; p OilAct (N) represents the filtered actual oil pressure at time N; the time difference between time N-1 and time N is a fixed update period ΔT (10ms in this example); p OilActRaw (N) represents the original actual oil pressure collected by the oil pressure sensor at time N.

[0162] In particular, when N=1, i.e. p OilAct (0) equals the original actual oil pressure p collected by the oil pressure sensor when the vehicle is first powered on. OilActRaw k is the filtering coefficient. The smaller the filtering coefficient k, the smoother the actual oil pressure after filtering. k is within the range of greater than 0 and less than 1.

[0163] Determine the state of VVT:

[0164] 1) When the VVT ​​is in a non-closed-loop control state (the specific conditions for the VVT ​​to be in a closed-loop control state can be found in patent CN202010977206.5 "VVT Phase Determination Method, Device, System and Storage Medium" which mentions that the VVT ​​activation is satisfied, i.e., the VVT ​​is in a closed-loop control state after the activation is satisfied), k = k1 is 0.35; 2) When the VVT ​​is in a closed-loop activated state and the actual VVT position is not close to the lock-up position, k = k2 is 0.3; 3) When the VVT ​​is in a closed-loop activated state and the actual VVT position is close to the lock-up position (in this example, the VVT ​​position being close to the lock-up position means that the VVT ​​phase is within 2° of the crankshaft angle near the lock-up position), k = k3 is 0.24.

[0165] In scenario 3) above, when the actual VVT position is close to the lock-up position, unstable pressure control may cause it to enter the lock-up position. To ensure that the VVT ​​can remain stable in the lock-up position, VVT phase control is more difficult at this time, requiring relatively stable oil pressure control. If the actual oil pressure fluctuates greatly, it may result in poor robustness of the oil pressure closed-loop control. In scenario 2), the oil pressure accuracy requirement in VVT closed-loop control is higher than in scenario 1 (in scenario 2, it is necessary to ensure the control accuracy of VVT). This example C1 will be updated and studied later.

[0166] If all of the following conditions are met, the subsequent actual oil pressure will be the filtered actual oil pressure p. OilAct The actual oil pressure is used for closed-loop oil pressure control; otherwise, the original actual oil pressure p is used. OilActRaw The actual oil pressure used for closed-loop oil pressure control:

[0167] 1.|p OilAct -p OilActRaw | Greater than the preset difference A (the preset difference in this example is 10 kPa):

[0168] 2. Original target oil pressure (referring to the currently disclosed target oil pressure, not updated or optimized by this invention) and filtered actual oil pressure p OilAct The difference should not exceed the preset range, which is ±10 kPa in this example;

[0169] 3. The original target oil pressure fluctuation range does not exceed ±5kPa, and the duration exceeds T0, where T0 is taken as 2s in this example.

[0170] At this point, the actual oil pressure fluctuates greatly, and the subsequent actual oil pressure is the filtered actual oil pressure p. OilAct The actual oil pressure used in the closed-loop control is limited to restrict large fluctuations in the target oil pressure, ensuring a small difference between the target oil pressure and the filtered actual oil pressure to improve the robustness of the closed-loop control; otherwise, the original actual oil pressure p is used. OilActRaw The actual oil pressure used for closed-loop oil pressure control.

[0171] However, note that during the switching between the two pressures, the absolute value of the rate of change should not exceed 2 kPa / 10 ms. After the transition is complete, the corresponding pressure should be used. The actual oil pressure used for coolant oil pressure control in subsequent descriptions will be referred to simply as the actual oil pressure.

[0172] Next, based on the target oil pressure (i.e., the original target oil pressure mentioned above) obtained through the technical solution in CN202010523747.0 "A Control Method and System for a Variable Displacement Oil Pump for Vehicles", the target oil pressure is referred to in this invention as the original target oil pressure T. CoolantDsrdRaw This invention dynamically optimizes the target oil pressure, specifically through four modes:

[0173] Mode 1: When the difference between the original target oil pressure and the actual oil pressure exceeds the preset value p1 (20 kPa in this example), and the actual oil pressure change rate is lower than the preset value dPa (-30 kPa / 10 ms in this example);

[0174] Then set the final target oil pressure to the original target oil pressure, and control the oil pump in open-loop mode with maximum displacement (i.e., control the oil pump with maximum boost capacity).

[0175] Mode 1 is maintained for at least T1 (to avoid excessive switching under different conditions and oil pressure fluctuations during the transition process). This T1 time depends on the difference p between the original target oil pressure and the actual oil pressure. Error And atmospheric temperature. When the atmospheric temperature is low and the difference between the original target oil pressure and the actual oil pressure is p... Error The larger the value, the more viscous the engine oil, and the longer the T1 time, in order to quickly establish oil pressure and achieve smooth engine starting. The T1 time is calibrated by ensuring that the engine speed is relatively stable during engine starting (the engine speed change rate during starting is not less than 20 rpm / 10 ms), and that the oil pressure fluctuation range does not exceed ±5 kPa within a preset time t1 (0.2 s in this example) after the engine successfully starts and exits this first condition. Based on this, the T1 calibration results in this example are as follows (this calibration result is from the vehicle development process; during different stages of the vehicle's life cycle, due to component aging and environmental changes, this T1 will be continuously updated and learned to better control oil pressure):

[0176]

[0177] In Mode 2, after exiting Mode 1 or when the conditions of Mode 1 are not met, if the difference between the original target oil pressure and the actual oil pressure exceeds a preset value p1, and the actual oil pressure change rate is not lower than a preset value dPa, and the duration is not less than T2, then the final target oil pressure is set to the original target oil pressure minus a preset value C1 (10kPa in this example), and the oil pump is controlled using "feedforward + PID" control, that is, the oil pressure is controlled by controlling the PWM duty cycle of the oil pump through PID (proportional-integral-derivative). For details, see patent CN202010523747.0 "A Control Method and System for a Variable Displacement Oil Pump for Vehicles";

[0178] The duration of Mode 2 should be no less than T2 (to avoid excessively frequent switching between different conditions and resulting oil pressure fluctuations during the transition). This T2 time depends on the difference p between the original target oil pressure and the actual oil pressure. Error And atmospheric temperature. When the atmospheric temperature is low and the difference between the original target oil pressure and the actual oil pressure is p... Error The larger the value, the more viscous the engine oil, and the longer the T2 time, in order to quickly establish oil pressure and achieve smooth engine starting. The T2 time is calibrated by ensuring that the engine speed is relatively stable during engine starting (the engine speed change rate during starting is not less than 20 rpm / 10 ms), and that the oil pressure fluctuation range does not exceed ±5 kPa within a preset time t1 (0.2 s in this example) after successfully starting the engine and exiting this second condition. Based on this, the T2 calibration results in this example are as follows (since the absolute value of the actual oil pressure change rate in mode 2 is smaller than that in mode 1, T2 is not greater than T1. This calibration result is from the vehicle development process; during different stages of the vehicle's life cycle, due to component aging and environmental changes, T2 will be continuously updated and learned to better control oil pressure):

[0179]

[0180] Mode 3: If the first two conditions are not met, and the difference between the original target oil pressure and the actual oil pressure does not exceed the preset value p1 but exceeds p2 (in this example, p2 is 5 kPa), and the actual oil pressure change rate is lower than the preset value dPa, the final target oil pressure is set to the original target oil pressure minus the preset value C2 (C2 < C1, in this example, 3 kPa). The oil pump control method is as follows:

[0181] The first step is to determine the difference between the original target oil pressure and the actual oil pressure, p. Error Determine the feedforward term Pct FF :

[0182] Pct FF =f1(T Coolant )×p Error +k(TCoolant )×f1(p TargetFinal ,n)+[1-k(T Coolant )]×f2(p TargetFinal (n)

[0183] Where f1(T) coolant (T) represents the engine coolant temperature. Coolant The function (when the engine coolant temperature is low, the engine oil is more viscous, and the oil pressure difference is greater, it is necessary to increase the oil pump duty cycle to improve the lubrication of the engine), f1(p Error ) is p Error The function, k(T) Coolant f1(p) is a weighting coefficient determined based on the engine coolant temperature. Targe tFinal f2(p) Targ etFinal (n) represents the oil pump control ratio after engine warm-up (calibration results at engine coolant temperature of 110℃ in this example) and at low temperature (calibration results at engine coolant temperature of -50℃ in this example), respectively. Both are determined by the final target oil pressure p. Targ etFinal It is determined together with the engine speed n.

[0184]

[0185] That is, f1(p) Targ etFinal f2(p) was calibrated at an engine coolant temperature of 110°C. Targ etFinal n) was calibrated at an engine coolant temperature of -50°C, while the values ​​for coolant temperatures between -50°C and 110°C were obtained by k(T). coolant It is obtained by linear interpolation.

[0186] Furthermore, the P item controls the percentage, Pct P =dp Error ×f1(dp Error )×f2(p Error ), dp Error oil pressure difference p Error rate of change, f1(dp) Error ) is dp Error The function, f2(p Error ) is p Error The function.

[0187] Furthermore, the percentage of control item I, Pct I Among them, the cumulative term Pct of item I IIncre For: Pct IIncre =dp Error ×f2(dp Error )×f3(p Error )-pct Saturation Item I control percentage PctI The initial value is 0. Specifically, the percentage of the I-term integral, Pct. I The value will be reset to zero when the third condition is met. The cumulative term Pct of term I is... IIncre The filter coefficient k1 is reset to zero when switching between different conditions. Where pct Saturation This refers to optimization when the percentage of the control process reaches saturation. It is calculated by Sum (the sum of the feedforward control percentage, the P-term control percentage, and the I-term control percentage from the previous moment) and the minimum limit Pct for the oil pump control percentage. min and maximum limit Pct max This is determined by Sum, where Sum equals Pct of the previous sampling period. FF +Pct p +Pct I :

[0188] 1) When Sum is not less than the minimum limit Pct min (This example uses 0%) or Sum (this example uses 100%) is not greater than the maximum limit Pct. max At that time, pct Saturation =0; This indicates that the percentage is within the limit, the control is normal, and there is no need to adjust the I-item accumulation item.

[0189] 2) When Sum is less than the minimum limit Pct min At that time, pct Saturation =k s ×(Sum-Pct min ());

[0190] 3) When Sum is greater than the maximum limit Pct max At that time, pct Saturation =k S ×(Sum-Pct max ());

[0191] Where k s The smoothing coefficient is set to 0.1 in this example.

[0192] Final I-item control percentage Pct I Equals the percentage of I-term control Pct in the previous sampling period (the sampling period in this example is 10ms). I (z) Add the cumulative term Pct of item I. IIncre get.

[0193] The final oil pump control duty cycle is equal to Pct of the current sampling period. FF +Pct P +Pct I .

[0194] The consideration of oil pressure difference and its rate of change in terms P and I is because in this method, the oil pressure difference is small, but the actual rate of change in oil pressure is too low. The control parameters must consider not only the oil pressure difference but also the rate of change in oil pressure to improve oil pressure fluctuations. The calibration effect in this case requires ensuring that the time for the oil pressure difference to exceed ±5 kPa does not exceed 0.5 s; Pct is calibrated based on this. FF Pct P and Pct I .

[0195] Mode 4: After exiting the first three modes or when none of the first three modes are met, if the difference between the original target oil pressure and the actual oil pressure does not exceed the preset value p1 but exceeds p2 (p2 is taken as 5 kPa in this example), and the actual oil pressure change rate is lower than the preset value dPa, the final target oil pressure is set to the original target oil pressure. The oil pump is controlled using "feedforward + PID" control, that is, the oil pressure is controlled by controlling the PWM duty cycle of the oil pump through PID (proportional-integral-derivative). Specifically, this is achieved through the technical solution of patent CN202010523747.0, "A Control Method and System for a Variable Displacement Oil Pump for Vehicles."

[0196] In cases other than the four modes mentioned above, the final target oil pressure is set to the original target oil pressure, and the oil pump does not operate, i.e., the oil pump control duty cycle is 0%. In this case, the oil pressure is not actively controlled to increase.

[0197] Finally, the preset values ​​C1 and C2, and the durations T1 and T2 are updated through self-learning. The specific update method is as follows:

[0198] If any of the following situations occur during the current driving cycle, the updated value will be saved by power-off and updated in the next driving cycle:

[0199] 1. If the oil pressure fluctuation exceeds ±5kPa during Mode 1, the preset value C1 will be updated to 0.98±0.1 times the previous value in the next driving cycle. If the oil pressure fluctuation does not exceed ±5kPa for CNT consecutive times (500 in this example), the preset value C1 will be updated to 1.02±0.1 times the previous value in the next driving cycle. Otherwise, the preset value C1 will remain unchanged from the previous value.

[0200] 2. If the oil pressure fluctuation exceeds ±5 kPa within the preset time t1 after exiting Mode 1, the maintenance time T1 of the next driving cycle will be updated to 1.02 ± 0.1 times the previous update value; if the oil pressure fluctuation does not exceed ±5 kPa for CNT consecutive times (500 in this example), the maintenance time T1 of the next driving cycle will be updated to 0.98 ± 0.1 times the previous update value; otherwise, the maintenance time T1 will remain unchanged from the previous update value.

[0201] 3. If the oil pressure fluctuation exceeds ±5 kPa during Mode 2, the preset value C2 will be updated to 0.95 ± 0.1 times the previous update value in the next driving cycle; if the oil pressure fluctuation does not exceed ±5 kPa for CNT consecutive times (500 in this example), the preset value C2 will be updated to 1.05 ± 0.1 times the previous update value in the next driving cycle; otherwise, the preset value C2 will remain unchanged from the previous update value.

[0202] 4. If the oil pressure fluctuation exceeds ±5 kPa within the preset time t1 after exiting Mode 2, the maintenance time T2 of the next driving cycle will be updated to 1.01 ± 0.1 times the previous update value; if the oil pressure fluctuation does not exceed ±5 kPa for CNT consecutive times (500 in this example), the maintenance time T2 of the next driving cycle will be updated to 0.99 ± 0.1 times the previous update value; otherwise, the maintenance time T2 will remain unchanged from the previous update value.

[0203] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0204] In the above embodiments of the present invention, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0205] In the several embodiments provided by this invention, it should be understood that the disclosed technical content can be implemented in other ways. The system embodiments described above are merely illustrative; for example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces, or indirect coupling or communication connection between units or modules, and may be electrical or other forms.

[0206] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0207] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0208] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes: USB flash drives, read-only storage media (ROM), random access storage media (RAM), portable hard drives, magnetic disks, optical disks, and other media capable of storing program code.

[0209] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for controlling automotive oil pressure, characterized in that, include: The original actual oil pressure of the engine is collected and filtered to obtain the filtered actual oil pressure. Obtain the current VVT state. When the VVT ​​state is in the closed-loop active state, set the oil pressure switching condition. When the oil pressure switching condition is met, use the filtered actual oil pressure as the actual oil pressure for oil pressure closed-loop control. Otherwise, use the original actual oil pressure as the actual oil pressure for oil pressure closed-loop control. Obtain the original target oil pressure, set the oil pressure dynamic control mode, and control the final target oil pressure of the vehicle according to the actual oil pressure; The conditions for setting the oil pressure switching include: The difference between the filtered actual oil pressure and the original actual oil pressure is greater than a preset difference. The difference between the original target oil pressure and the filtered actual oil pressure does not exceed a preset range; The original target oil pressure fluctuation range does not exceed the preset fluctuation range, and the duration exceeds T0; The hydraulic dynamic control modes include: Mode 1: The difference between the original target oil pressure and the actual oil pressure exceeds a preset value. Furthermore, the rate of change of the actual oil pressure is lower than the preset value. Then the final target oil pressure is set to the original target oil pressure, and the oil pump is controlled in open-loop mode with maximum displacement, and the maintenance time is not less than T1; Mode 2: The difference between the original target oil pressure and the actual oil pressure exceeds a preset value. And the rate of change of the actual oil pressure is not lower than the preset value. If the final target oil pressure is set to the original target oil pressure minus the preset value C1, the oil pump control is performed using a feedforward combined with PID control, and the maintenance time is not less than T2. Mode 3, where the difference between the original target oil pressure and the actual oil pressure does not exceed a preset value. But more than Furthermore, the rate of change of the actual oil pressure is lower than the preset value. Then the final target oil pressure is set to the original target oil pressure minus the preset value C2, where C2 < C1, and the oil pump is controlled by adjusting the P and I terms in the PID controller. Mode 4: The difference between the original target oil pressure and the actual oil pressure does not exceed a preset value. But more than And the rate of change of the actual oil pressure is not lower than the preset value. Then the final target oil pressure is set to the original target oil pressure, and the oil pump control is performed using a feedforward combined with PID control. The priority of modes 1 through 4 decreases progressively.

2. The method for controlling automotive oil pressure as described in claim 1, characterized in that, The current VVT status includes: When VVT is in a non-closed-loop control state; When the VVT ​​is in closed-loop active state and the actual VVT position is not close to the locking position; When the VVT ​​is in the closed-loop active state and the actual VVT position is close to the locked position.

3. The method for controlling automotive oil pressure as described in claim 1, characterized in that, It also includes self-learning updates of preset values ​​C1 and C2, and durations T1 and T2, specifically: If the oil pressure fluctuation exceeds ±5 kPa in Mode 1, the preset value C1 will be updated to 0.98 ± 0.1 times the previous value in the next driving cycle; if the oil pressure fluctuation does not exceed ±5 kPa for any of the CNT consecutive driving cycles, the preset value C1 will be updated to 1.02 ± 0.1 times the previous value in the next driving cycle; otherwise, the preset value C1 will remain unchanged from the previous value. If the oil pressure fluctuation exceeds ±5 kPa within the preset time t1 after exiting mode 1, the maintenance time T1 of the next driving cycle will be updated to 1.02 ± 0.1 times the previous update value; if the oil pressure fluctuation does not exceed ±5 kPa for any of the consecutive CNT cycles, the maintenance time T1 of the next driving cycle will be updated to 0.98 ± 0.1 times the previous update value; otherwise, the maintenance time T1 will remain unchanged from the previous update value. If the oil pressure fluctuation exceeds ±5 kPa in Mode 2, the preset value C2 will be updated to 0.95 ± 0.1 times the previous value in the next driving cycle; if the oil pressure fluctuation does not exceed ±5 kPa for any of the next CNT cycles, the preset value C2 will be updated to 1.05 ± 0.1 times the previous value in the next driving cycle; otherwise, the preset value C2 will remain unchanged from the previous value. If the oil pressure fluctuation exceeds ±5 kPa within the preset time t1 after exiting mode 2, the maintenance time T2 of the next driving cycle will be updated to 1.01 ± 0.1 times the previous update value; if the oil pressure fluctuation does not exceed ±5 kPa for any of the consecutive CNT cycles, the maintenance time T2 of the next driving cycle will be updated to 0.99 ± 0.1 times the previous update value; otherwise, the maintenance time T2 will remain unchanged from the previous update value.

4. An automotive oil pressure control system, characterized in that, include: The data acquisition module is used to collect the engine's original actual oil pressure, perform filtering processing, and obtain the filtered actual oil pressure. The hydraulic pressure switching module is used to obtain the current VVT status. When the VVT ​​status is in the closed-loop active state, the hydraulic pressure switching conditions are set. When the hydraulic pressure switching conditions are met, the filtered actual hydraulic pressure is used as the actual hydraulic pressure for hydraulic pressure closed-loop control. Otherwise, the original actual hydraulic pressure is used as the actual hydraulic pressure for hydraulic pressure closed-loop control. The control module is used to acquire the original target oil pressure, set the oil pressure dynamic control mode, and control the final target oil pressure of the vehicle according to the actual oil pressure. The conditions for setting the oil pressure switching include: The difference between the filtered actual oil pressure and the original actual oil pressure is greater than a preset difference. The difference between the original target oil pressure and the filtered actual oil pressure does not exceed a preset range; The original target oil pressure fluctuation range does not exceed the preset fluctuation range, and the duration exceeds T0; The hydraulic dynamic control modes include: Mode 1: The difference between the original target oil pressure and the actual oil pressure exceeds a preset value. Furthermore, the rate of change of the actual oil pressure is lower than the preset value. Then the final target oil pressure is set to the original target oil pressure, and the oil pump is controlled in open-loop mode with maximum displacement, and the maintenance time is not less than T1; Mode 2: The difference between the original target oil pressure and the actual oil pressure exceeds a preset value. And the rate of change of the actual oil pressure is not lower than the preset value. If the final target oil pressure is set to the original target oil pressure minus the preset value C1, the oil pump control is performed using a feedforward combined with PID control, and the maintenance time is not less than T2. Mode 3, where the difference between the original target oil pressure and the actual oil pressure does not exceed a preset value. But more than Furthermore, the rate of change of the actual oil pressure is lower than the preset value. Then the final target oil pressure is set to the original target oil pressure minus the preset value C2, where C2 < C1, and the oil pump is controlled by adjusting the P and I terms in the PID controller. Mode 4: The difference between the original target oil pressure and the actual oil pressure does not exceed a preset value. But more than And the rate of change of the actual oil pressure is not lower than the preset value. Then the final target oil pressure is set to the original target oil pressure, and the oil pump control is performed using a feedforward combined with PID control. The priority of modes 1 through 4 decreases progressively.

5. The automotive oil pressure control system as described in claim 4, characterized in that, The current VVT status includes: When VVT is in a non-closed-loop control state; When the VVT ​​is in closed-loop active state and the actual VVT position is not close to the locking position; When the VVT ​​is in the closed-loop active state and the actual VVT position is close to the locked position.

6. The automotive oil pressure control system as described in claim 4, characterized in that, It also includes self-learning updates of preset values ​​C1 and C2, and durations T1 and T2, specifically: If the oil pressure fluctuation exceeds ±5 kPa in Mode 1, the preset value C1 will be updated to 0.98 ± 0.1 times the previous value in the next driving cycle; if the oil pressure fluctuation does not exceed ±5 kPa for any of the CNT consecutive driving cycles, the preset value C1 will be updated to 1.02 ± 0.1 times the previous value in the next driving cycle; otherwise, the preset value C1 will remain unchanged from the previous value. If the oil pressure fluctuation exceeds ±5 kPa within the preset time t1 after exiting mode 1, the maintenance time T1 of the next driving cycle will be updated to 1.02 ± 0.1 times the previous update value; if the oil pressure fluctuation does not exceed ±5 kPa for any of the consecutive CNT cycles, the maintenance time T1 of the next driving cycle will be updated to 0.98 ± 0.1 times the previous update value; otherwise, the maintenance time T1 will remain unchanged from the previous update value. If the oil pressure fluctuation exceeds ±5 kPa in Mode 2, the preset value C2 will be updated to 0.95 ± 0.1 times the previous value in the next driving cycle; if the oil pressure fluctuation does not exceed ±5 kPa for any of the next CNT cycles, the preset value C2 will be updated to 1.05 ± 0.1 times the previous value in the next driving cycle; otherwise, the preset value C2 will remain unchanged from the previous value. If the oil pressure fluctuation exceeds ±5 kPa within the preset time t1 after exiting mode 2, the maintenance time T2 of the next driving cycle will be updated to 1.01 ± 0.1 times the previous update value; if the oil pressure fluctuation does not exceed ±5 kPa for any of the consecutive CNT cycles, the maintenance time T2 of the next driving cycle will be updated to 0.99 ± 0.1 times the previous update value; otherwise, the maintenance time T2 will remain unchanged from the previous update value.

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