Clutch control method and device, storage medium and program product

Abstract

The invention relates to a clutch control method and device, a storage medium and a program product, and relates to the technical field of vehicle control. The method is implemented by a vehicle with an automatic engine start-stop system, and comprises the following steps: predicting uprush rotating speed information of engine restart according to vehicle operation condition information under the conditions that the automatic engine start-stop system works and an engine automatically flames out; determining first oil pressure according to the uprush rotating speed information; the first oil pressure is used for making the output torque of the clutch not larger than the perceptible minimum impact transmission torque; under the condition that the engine automatic start-stop system works and the engine is restarted, the clutch is controlled to be in a semi-linkage state through the electronic pump according to the first oil pressure; acquiring second oil pressure; the second oil pressure is the oil pressure output by the mechanical pump after the engine is restarted; and under the condition that the second oil pressure is equal to the first oil pressure, the clutch is controlled to be in a pressed state through the mechanical pump. According to the invention, the stability of moving forward again after the vehicle stops can be improved.

Description

Technical Field

[0001] The present application relates to the field of vehicle control technology, and in particular to a clutch control method, device, storage medium and program product. Background Art

[0002] In the event of a temporary stop during driving (such as waiting at a red light), the engine of a traditional fuel vehicle can run at the lowest speed. At this time, the vehicle is not driving but will consume fuel.

[0003] In the related technology, the automatic start-stop function of the engine allows the vehicle to automatically shut down when waiting at a red light, and automatically restart the engine when continuing to move forward; therefore, the automatic start-stop function of the engine can achieve the effect of energy conservation, emission reduction and lower fuel consumption.

[0004] However, restarting the engine after it automatically shuts down is usually accompanied by impact and vibration of the entire vehicle, which can easily bring an uncomfortable driving experience to the owner. Summary of the invention

[0005] The embodiments of the present application provide a clutch control method, device, storage medium and program product, which can improve the stability of the vehicle when the engine is restarted after automatic shutdown. The technical solution is as follows:

[0006] In one aspect, a clutch control method is provided, the method being implemented by a vehicle having an automatic engine start-stop system, the method comprising:

[0007] When the engine automatic start-stop system is working and the engine is automatically shut down, predicting the engine restart speed information based on the vehicle operating condition information; the vehicle operating condition information at least includes the state information of the engine, and the engine restart speed information is used to indicate the engine speed increase process after the engine is restarted;

[0008] Determining a first oil pressure according to the impulse speed information; the first oil pressure is used to ensure that the output torque of the clutch is not greater than the perceptible minimum impact transmission torque;

[0009] When the engine automatic start-stop system is working and the engine is restarted, the clutch is controlled to be in a semi-clutch state by the electronic pump according to the first oil pressure;

[0010] Acquiring a second oil pressure; the second oil pressure is the oil pressure output by the mechanical pump after the engine is restarted;

[0011] When the second oil pressure is equal to the first oil pressure, the clutch is controlled to be in a clamping state by the mechanical pump.

[0012] In one aspect, a vehicle control system is provided, the system comprising an engine control unit and a transmission control unit;

[0013] The engine control unit is used to predict the upward speed information of the engine restart according to the vehicle operating condition information when the engine automatic start-stop system is working and the engine is automatically shut down; the vehicle operating condition information at least includes the state information of the engine, and the upward speed information is used to indicate the rising process of the speed of the engine after restarting;

[0014] The transmission control unit is used to determine a first oil pressure according to the upward impact speed information; the first oil pressure is used to make the output torque of the clutch not greater than the perceptible minimum impact transmission torque;

[0015] The transmission control unit is configured to control the clutch to be in a semi-clutch state through the electronic pump according to the first oil pressure when the engine automatic start-stop system is working and the engine is restarted;

[0016] The transmission control unit is used to obtain a second oil pressure; the second oil pressure is the oil pressure output by the mechanical pump after the engine is restarted;

[0017] The transmission control unit is used to control the clutch to be in a tightening state through the mechanical pump when the second oil pressure is equal to the first oil pressure.

[0018] In another aspect, a clutch control device is provided, the device comprising:

[0019] A speed prediction module, used for predicting the speed information of the engine restarting according to the vehicle operating condition information when the engine automatic start-stop system is working and the engine is automatically shut down; the vehicle operating condition information at least includes the state information of the engine, and the speed information of the engine restarting is used to indicate the speed increase process after the engine restarts;

[0020] An oil pressure determination module, configured to determine a first oil pressure according to the impulse speed information; the first oil pressure is configured to ensure that the output torque of the clutch is not greater than a perceptible minimum impact transmission torque;

[0021] a first control module, configured to control the clutch to be in a semi-clutch state through the electronic pump according to the first oil pressure when the engine automatic start-stop system is working and the engine is restarted;

[0022] An oil pressure acquisition module, used for acquiring a second oil pressure; the second oil pressure is the oil pressure output by the mechanical pump after the engine is restarted;

[0023] The second control module is used to control the clutch to be in a clamping state through the mechanical pump when the second oil pressure is equal to the first oil pressure.

[0024] In a possible implementation, the oil pressure determination module is used to determine the output torque of the clutch according to the upward stroke speed information;

[0025] The oil pressure determination module is used to determine the first oil pressure according to the output torque of the clutch.

[0026] In a possible implementation, the oil pressure determination module is used to obtain a torque difference value; the torque difference value is used to indicate a difference between the output torque of the clutch and the perceptible minimum impact transmission torque;

[0027] The oil pressure determination module is used to determine the first oil pressure according to the torque difference.

[0028] In a possible implementation manner, the device further includes:

[0029] An electronic pump starting module, used for starting the electronic pump when the engine automatic start-stop system is working and the engine is automatically shut down;

[0030] A mechanical pump starting module, used for starting the mechanical pump when the engine automatic start-stop system is working and the engine is restarted;

[0031] The electronic pump shutoff module is used to shut off the electronic pump when the second oil pressure is equal to the first oil pressure.

[0032] In one possible implementation, the engine status information indication includes missing tooth position information of the engine and water temperature information of the engine; the vehicle operating condition information also includes ambient temperature information of the vehicle, battery capacity of the vehicle and oil temperature information of the transmission.

[0033] On the other hand, a computer device is provided, which includes a processor and a memory, wherein the memory stores at least one instruction, at least one program, a code set or an instruction set, and the at least one instruction, the at least one program, the code set or the instruction set is loaded and executed by the processor to implement the clutch control method as described above.

[0034] On the other hand, a computer-readable storage medium is provided, wherein at least one instruction, at least one program, code set or instruction set is stored in the storage medium, and the at least one instruction, the at least one program, the code set or instruction set is loaded and executed by a processor to implement the clutch control method as described above.

[0035] In another aspect, a computer program product is provided, the computer program product comprising a computer program, the computer program being stored in a computer-readable storage medium. A processor of a computer device reads the computer program from the computer-readable storage medium, and the processor executes the computer program, so that the computer device executes the clutch control method provided in the above-mentioned various optional implementations.

[0036] The technical solution provided by this application may have the following beneficial effects:

[0037] By using the vehicle status information when the engine is shut down, the upward speed when the engine is restarted can be predicted; then, combined with the corresponding perceptible minimum impact transmission torque of the vehicle, the oil pressure of the transmission can be controlled, and the clutch can be controlled to be in a semi-clutch state, so that the impact force when the engine restarts will not give the driver of the vehicle a noticeable sense of movement, thereby improving the stability of the vehicle moving forward again after stopping. In addition, this solution can avoid a large change in the clutch state due to too low oil pressure in the oil circuit during engine shutdown by alternating the use of electronic pumps and mechanical pumps; after the engine is restarted, when the oil pressures of the mechanical pump and the electronic pump are equal, smooth switching of the oil circuit can be achieved.

[0038] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0040] Figure 1 is a schematic diagram of an implementation environment of a clutch control method provided by an exemplary embodiment of the present application;

[0041] Figure 2 is a flow chart of a clutch control method provided by an exemplary embodiment of the present application;

[0042] Figure 3 is a schematic diagram of an engine speed provided by an exemplary embodiment of the present application;

[0043] Figure 4 is a schematic diagram of a starting system for an AT / CVT transmission start-stop function provided by an exemplary embodiment of the present application;

[0044] Figure 5 is a block diagram of a clutch control device provided by an exemplary embodiment of the present application;

[0045] Figure 6It is a structural diagram of a computer device provided by an exemplary embodiment of the present application. DETAILED DESCRIPTION

[0046] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below with reference to the accompanying drawings.

[0047] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0048] The terms used in the present disclosure are for the purpose of describing specific embodiments only and are not intended to limit the present disclosure. The singular forms "a", "said" and "the" used in the present disclosure and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise.

[0049] It should be understood that although the terms first, second, etc. may be used in the present disclosure to describe various information, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present disclosure, a first parameter may also be referred to as a second parameter, and similarly, a second parameter may also be referred to as a first parameter. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0050] To facilitate understanding, some concepts involved in this application are explained below.

[0051] 1) Engine start: The engine is divided into two major mechanisms, including the crank-connecting rod mechanism and the valve mechanism, and five major systems, including the ignition system, fuel supply system, cooling system, lubrication system, and starting system. The engine start involves the coordinated work of multiple components. The battery-powered starting system drives the engine to rotate, the ignition system ignites at the appropriate time, and the fuel supply system provides an appropriate amount of fuel, so that the engine changes from a stationary state to a normal working state, completing the start process. Among them, the engine start conditions include:

[0052] ① The battery has sufficient power: The battery needs to have enough power to supply power to the starter;

[0053] ② The starting system is normal: The starter of the starting system needs to work normally to provide enough torque to turn the engine;

[0054] ③ The ignition system is normal: The ignition system needs to be able to generate enough spark to ignite the fuel-gas mixture;

[0055] ④ The fuel supply system is normal: The fuel supply system needs to be able to provide an appropriate amount of fuel to the cylinder;

[0056] ⑤ The engine temperature is suitable: Under low temperature conditions, additional preheating measures may be required to help the engine start.

[0057] 2) Stop & Start (STT): STT is an automotive technology designed to improve fuel economy and reduce emissions. It allows the vehicle to automatically shut down the engine when temporarily stopping (such as waiting for a red light or in traffic jams) and quickly restart the engine when continuing to drive. Therefore, STT is suitable for urban road conditions and is an auxiliary fuel saving method.

[0058] STT technology implants a reinforced motor with idle start-stop function in the engine, so that when the vehicle meets the idle stop conditions, the engine is completely turned off and does not work; when the vehicle needs to start again, the idle start-stop motor system including the reinforced motor can quickly respond to the user's start command, quickly start the engine, and connect instantly, thereby reducing fuel consumption and exhaust emissions.

[0059] 3) Transmission: Also known as a gearbox, it is an important component of the vehicle transmission system, which can change the torque and speed of the engine output to adapt to different driving conditions. According to the different transmission methods, the transmission can be divided into manual transmission and automatic transmission. Among them, the technical solution of the present application is applicable to automatic transmissions with torque converters, such as automatic transmissions (AT) and continuously variable transmissions (CVT).

[0060] 4) Torque converter: Also known as "turbo torque converter" or "dynamic torque converter", it transmits torque through liquid (such as transmission oil) and has the functions of torque gain and smooth shifting. The torque converter consists of a pump wheel, a turbine and a guide wheel. The pump wheel is connected to the engine. When the engine is running, the pump wheel rotates and can push the liquid to the turbine through rotation. The turbine is connected to the transmission input shaft. When the liquid flows from the pump wheel to the turbine, the turbine rotates and transmits the torque to the transmission. The guide wheel is located between the pump wheel and the turbine and is equipped with a one-way clutch. The guide wheel can increase the output torque of the turbine. The one-way clutch can ensure that the guide wheel can only rotate in one direction to prevent the liquid from directly returning to the pump wheel from the turbine.

[0061] 5) Three states of the clutch:

[0062] ① Disengaged state: In the disengaged state, the clutch is completely disengaged, and there is no torque transmission between the engine and the transmission system. Even if the engine is running, it will not drive the wheels to rotate;

[0063] ② Semi-clutch state: In the semi-clutch state, the clutch is partially engaged, and there is a certain torque transmission between the engine and the transmission system;

[0064] ③Compression state: In the compression state, the clutch is fully engaged, and maximum torque transmission can be achieved between the engine and the transmission system.

[0065] Please refer to Figure 1 , which shows a schematic diagram of an implementation environment of a clutch control method provided by an exemplary embodiment of the present application. Figure 1 As shown, the implementation environment may include: a vehicle with an automatic engine start-stop system, wherein the vehicle includes a vehicle control system 110 and a plurality of vehicle mechanical structures 120 .

[0066] The vehicle control system 110 may include a central control unit of the vehicle and a sub-control unit (such as an electronic control unit, ECU) connected to the central control unit bus. The sub-controller may include but is not limited to one or more of the following: an engine control unit 110a, a transmission control unit 110b.

[0067] The above-mentioned multiple vehicle mechanical devices 120 are controlled by the vehicle control system 110 , and the vehicle mechanical devices 120 may include but are not limited to one or more of the following: an engine 120 a and a gearbox 120 b .

[0068] The engine 120a is controlled by an engine control unit 110a, the gearbox 120b is controlled by a gearbox control unit 110b, and the gearbox 120b may include but is not limited to one or more of the following: a torque converter 120b1, a mechanical pump 120b2, an electronic pump 120b3, and a clutch 120b4.

[0069] For example, in Figure 1In the system shown, when the engine automatic start-stop system is working and the engine is automatically shut down, the engine control unit 110a can predict the engine restarting surge speed information according to the vehicle operating condition information; the vehicle operating condition information at least includes the engine state information, and the surge speed information is used to indicate the rising process of the engine speed after restarting; then, the engine control unit 110a can send the predicted surge speed information to the bus; accordingly, the transmission control unit 110b can obtain the above-mentioned surge speed information from the bus; then, according to the surge speed information, the transmission control unit 110b can determine the first oil pressure; the first oil pressure is used to make the output torque of the clutch not greater than the perceptible minimum impact transmission torque; when the engine automatic start-stop system is working and the engine is restarted, the transmission control unit 110b controls the clutch to be in a semi-clutch state through the electronic pump according to the first oil pressure; then, the transmission control unit 110b obtains the second oil pressure; the second oil pressure is the oil pressure output by the mechanical pump after the engine is restarted; when the second oil pressure is equal to the first oil pressure, the transmission control unit 110b controls the clutch to be in a clamped state through the mechanical pump.

[0070] Please refer to Figure 2 , which shows a flow chart of a clutch control method provided by an exemplary embodiment of the present application. The method is implemented by a vehicle with an engine automatic start-stop (STT) system and can be executed by a vehicle control system of the vehicle. Optionally, the vehicle can be Figure 1 The vehicle in the system shown. Figure 2 As shown, the method may include step 210 , step 220 , step 230 , step 240 and step 250 .

[0071] Step 210: When the engine automatic start-stop system is working and the engine is automatically shut down, predict the engine restart speed information based on the vehicle operating condition information; the vehicle operating condition information includes at least the engine status information, and the engine restart speed information is used to indicate the speed increase process after the engine is restarted.

[0072] The above-mentioned engine automatic start-stop system is working, which means that the vehicle's engine automatic start-stop (STT) system is not turned off and works normally. During the engine restart process, the first half of the starter speed increase process relies on the starter's drag, and the second half of the engine speed increase process relies on the engine's own work. For example, Figure 3 As shown, 0.1s after the engine restarts and the speed reaches 120Rps, the engine speed starts to rise until the maximum value of the rising speed is 1400Rps.

[0073] For example, when the engine automatic start-stop system is working and the engine is automatically shut down, the engine control unit in the vehicle control system can collect the above vehicle operating condition information through various sensors on the vehicle. The above sensors include but are not limited to one or more of the following: engine temperature sensor, coolant temperature sensor, battery voltage sensor, ambient temperature sensor.

[0074] The developer can pre-set the prediction method of the above-mentioned upper impulse speed information so that the vehicle control system can predict the upper impulse speed information according to the prediction method. For example, the above-mentioned prediction of the upper impulse speed information of the engine restart according to the vehicle operating condition information can be implemented as follows: from the upper impulse speed table, the upper impulse speed information corresponding to the vehicle operating condition information is searched; wherein the upper impulse speed table can indicate the corresponding relationship between the engine model, the vehicle operating condition information and the upper impulse speed information.

[0075] For another example, the prediction of the engine restart surge speed information based on the vehicle operating condition information may also be implemented as follows: the vehicle operating condition information is input into a preset calculation formula to calculate and obtain the corresponding surge speed information.

[0076] For another example, the above-mentioned prediction of the upward speed information of the engine restart based on the vehicle operating condition information can also be implemented as follows: the vehicle operating condition information is input into the speed prediction model to obtain the upward speed information output by the speed prediction model; wherein the speed prediction model is a machine learning model obtained by training with vehicle operating condition information samples and upward speed information samples corresponding to the vehicle operating condition information samples.

[0077] It should be noted that when the engine automatic start-stop system is working and the engine is automatically shut down, the transmission control unit in the vehicle control system can control the electronic pump to start working, and the oil pressure corresponding to the electronic pump can be accurately controlled by the transmission control unit.

[0078] Step 220: Determine a first oil pressure according to the upward impact speed information; the first oil pressure is used to ensure that the output torque of the clutch is not greater than the perceptible minimum impact transmission torque.

[0079] It should be noted that the torque output by the engine is different at different speeds. In the embodiment of the present application, the transmission control unit can predict the rising process of the torque transmitted to the transmission input shaft after the engine is restarted based on the overshoot speed information.

[0080] Exemplarily, after acquiring the above-mentioned impulse speed information, the engine control unit may send the above-mentioned impulse speed information to the bus, and the transmission control unit acquires the above-mentioned impulse speed information from the bus and determines the first oil pressure according to the impulse speed information.

[0081] The first oil pressure refers to the pressure of the transmission oil in the transmission, and the pressure is transmitted to the clutch, so that the clutch is in one of a disengaged state, a semi-clutched state, and a clamped state.

[0082] In the embodiment of the present application, the transmission control unit can obtain the torque transmitted to the clutch output end according to the output torque information. If the torque transmitted to the clutch output end is less than or equal to the perceptible minimum impact transmission torque, the first oil pressure can be a larger value; if the torque transmitted to the clutch output end is greater than the perceptible minimum impact transmission torque, the first oil pressure can be a smaller value, so that the clutch output torque is not greater than the perceptible minimum impact transmission torque.

[0083] The above-mentioned perceptible minimum impact transfer torque is used to indicate the maximum torque allowed by the vehicle during the engine startup process. Exceeding the above-mentioned perceptible minimum impact transfer torque may cause the driver and passengers to feel obvious impact or vibration. Exemplarily, the above-mentioned perceptible minimum impact transfer torque can be determined by the developer based on multiple tests; for example, the developer can set multiple clutch output torque test values ​​for the same vehicle model and the same transmission system, test the impact force of the output torque test values ​​of multiple clutches on the vehicle one by one, and then determine the minimum impact transfer torque perceptible to the driver and passengers.

[0084] For example, developers can determine the correspondence between different vehicle models, different transmission systems and the minimum perceptible impact transfer torque based on multiple tests of different vehicle models and different transmission systems; accordingly, the transmission control unit can determine the corresponding minimum perceptible impact transfer torque based on the current vehicle model and transmission system.

[0085] Step 230: When the engine automatic start-stop system is working and the engine is restarted, the clutch is controlled to be in a semi-clutch state through the electronic pump according to the first oil pressure.

[0086] That is to say, when the engine is restarted, the transmission control unit of the vehicle control system can set the oil pressure of the electronic pump to the first oil pressure, providing pressure to the clutch, so that the clutch is in a semi-clutch state.

[0087] When the clutch is in a semi-engaged state, the torque of the engine output shaft is not fully transmitted to the transmission system.

[0088] Step 240: Obtain a second oil pressure; the second oil pressure is the oil pressure output by the mechanical pump after the engine is restarted.

[0089] Among them, when the engine automatic start-stop system is working and the engine is restarted, the engine can drive the mechanical pump to start working and build up oil pressure.

[0090] In the embodiment of the present application, the transmission control unit of the vehicle control system can obtain the second oil pressure corresponding to the mechanical pump through the oil pressure sensor of the mechanical pump.

[0091] Step 250: When the second oil pressure is equal to the first oil pressure, the clutch is controlled to be in a clamped state through a mechanical pump.

[0092] The second oil pressure is equal to the first oil pressure, which means that the second oil pressure established by the mechanical pump gradually increases and reaches the first oil pressure corresponding to the electronic pump. At this time, the gearbox control unit of the vehicle control system can realize oil circuit reversal through the solenoid valve, and the mechanical pump provides oil pressure to the clutch and turns off the electronic pump; as the corresponding oil pressure of the mechanical pump further increases, the clutch is in a tightened state, and the vehicle completes the steady start process.

[0093] In summary, the scheme shown in the embodiment of the present application can predict the upward speed when the engine is restarted by the state information of the vehicle when the engine is stopped; then, combined with the corresponding perceptible minimum impact transmission torque of the vehicle, the oil pressure of the transmission can be controlled, and the clutch can be controlled to be in a semi-clutch state, so that the impact force when the engine is restarted will not give the driver of the vehicle a noticeable sense of movement, thereby improving the stability of the vehicle moving forward again after stopping. In addition, this scheme can avoid a large change in the clutch state due to too low oil pressure in the oil circuit during engine shutdown by alternating the use of electronic pumps and mechanical pumps; after the engine is restarted, when the oil pressures of the mechanical pump and the electronic pump are equal, smooth switching of the oil circuit can be achieved.

[0094] Based on the above Figure 2 In the solution in the embodiment shown, in a possible implementation solution, the above step 220 can be implemented as follows:

[0095] Step 220a: Determine the output torque of the clutch according to the upward speed information.

[0096] It should be noted that different engine speeds correspond to different output torques. Accordingly, the torque transmitted to the transmission input shaft by the engine output torque is also different after being transmitted by the torque converter and consumed by the mechanical pump and finally transmitted to the clutch output shaft.

[0097] The output torque of the clutch may correspond to the torque that can be transmitted to the wheels after the engine is started.

[0098] For example, the transmission control unit can determine the output torque of the engine corresponding to the maximum upward speed according to the upward speed information of the engine; then, according to the torque loss of the pump wheel and turbine of the torque converter during the hydraulic transmission process, and the torque consumed by the mechanical pump to establish oil pressure, determine the torque transmitted to the clutch output shaft. For example, the transmission control unit can use the value obtained by subtracting the torque loss of the torque converter and the torque consumed by the mechanical pump from the output torque of the engine as the torque of the clutch output shaft.

[0099] Exemplarily, the output torque of the engine corresponding to the above maximum upward speed can be calculated by the following formula:

[0100]

[0101] Among them, T is the output torque of the engine (unit: Newton meter Nm), P is the power of the engine (unit: kilowatt kW), and N is the maximum upward speed of the engine (unit: revolutions per second Rps).

[0102] For example, the output torque of the engine corresponding to the maximum overshoot speed can also be read from the torque-speed curve of the engine. The torque-speed curve of the engine can be preset by the developer to display the output torque of the engine at different speeds.

[0103] Step 220b: Determine the first oil pressure according to the output torque of the clutch.

[0104] In the embodiment of the present application, the transmission control unit can determine a reasonable first oil pressure based on the obtained output torque of the clutch, and the first oil pressure is used to make the output torque of the clutch less than or equal to the minimum perceptible impact transmission torque.

[0105] The embodiment of the present application provides a feasible solution for determining the first oil pressure according to the upward stroke speed information, which fully considers the transmission of the torque converter and the consumption of the mechanical pump, and can improve the accuracy of the first oil pressure.

[0106] Based on the solutions shown in the above embodiments of the present application, in a possible implementation scheme, the above step 220b can be implemented as follows:

[0107] Obtaining a torque difference value; the torque difference value is used to indicate the difference between the clutch output torque and the perceptible minimum impact transmission torque;

[0108] The first oil pressure is determined according to the torque difference.

[0109] The torque difference may be the difference between the clutch output torque and the perceptible minimum impact transmission torque. When the difference is negative or zero, it means that the driver and passengers will not feel obvious impact or vibration, and at this time, the first oil pressure may correspond to a larger oil pressure value; when the difference is positive, it means that the driver and passengers may feel obvious impact or vibration, and at this time, the first oil pressure may correspond to a smaller oil pressure value.

[0110] Exemplarily, the developer may pre-set a comparison table between the torque difference and the first oil pressure, and store the comparison table in the transmission control unit; accordingly, the transmission control unit may search the comparison table for the first oil pressure corresponding to the current torque difference.

[0111] In an embodiment of the present application, the transmission control unit can determine the first oil pressure that meets the conditions by comparing the output torque of the clutch and the size of the minimum perceptible impact transmission torque, so that the driver and passengers will not feel obvious impact or vibration, thereby improving the smoothness of the engine starting process.

[0112] Based on the solutions shown in the above embodiments of the present application, in a possible implementation scheme, the above clutch control method further includes the following steps:

[0113] When the engine automatic start-stop system is working and the engine is automatically shut down, start the electronic pump;

[0114] When the engine automatic start-stop system is working and the engine is restarted, the mechanical pump is started;

[0115] When the second oil pressure is equal to the first oil pressure, the electronic pump is turned off.

[0116] In an embodiment of the present application, when the engine is automatically shut down, the mechanical pump automatically stops working. At this time, in order to ensure lubrication and cooling inside the transmission, the transmission control unit can start the electronic pump to maintain the necessary oil pressure.

[0117] When the engine restarts, the mechanical pump starts to work, and the electronic pump continues to work while building up oil pressure. When the second oil pressure built up by the mechanical pump reaches the first oil pressure maintained by the electronic pump, the oil pressures of the mechanical pump and the electronic pump are balanced. After the solenoid valve completes the oil circuit reversal, the transmission control unit can turn off the electronic pump, and the mechanical pump continues to supply oil pressure.

[0118] The embodiment of the present application provides the start and stop timing of the electronic pump and the mechanical pump, which may specifically include: when the engine is automatically shut down, the mechanical pump stops working and the electronic pump is started; when the engine is restarted, the mechanical pump is started and the oil pressure is established; when the oil pressure of the mechanical pump reaches the oil pressure of the electronic pump, the oil circuit is switched through the solenoid valve, that is, the oil circuit is transferred from the electronic pump to the mechanical pump, and the electronic pump is turned off. This solution can avoid a large change in the clutch state due to too low oil pressure in the oil circuit during engine shutdown by alternating the use of the electronic pump and the mechanical pump; after the engine is restarted, when the oil pressures of the mechanical pump and the electronic pump are equal, a smooth switching of the oil circuit can be achieved.

[0119] Based on the solutions shown in the above-mentioned embodiments of the present application, in a possible implementation scheme, the engine status information indication includes the engine's missing tooth position information and the engine's water temperature information; the vehicle operating condition information also includes the vehicle's ambient temperature information, the vehicle's battery capacity and the transmission's oil temperature information.

[0120] Among them, the missing tooth position information of the above-mentioned engine is used to indicate one or several missing tooth positions on the engine crankshaft signal disk (also called signal gear ring or signal wheel), and the missing tooth position can help the engine control unit determine the position of the engine crankshaft, and then determine the various working cycles of the engine. For example, the missing tooth position can assist the engine control unit in determining the ignition and injection timing to ensure that the engine ignites and injects fuel at the correct time. Exemplarily, the engine control unit can obtain the above-mentioned missing tooth position information through a speed sensor and a phase relationship; wherein the phase relationship refers to the engine valve timing, that is, the angle of the timing of opening and closing of the intake valve and the exhaust valve relative to the crankshaft position.

[0121] The water temperature information of the engine is used to indicate the temperature of the engine coolant, which can reflect the overall thermal state of the engine and affect the starting performance of the engine. When the engine is stopped, the temperature of the coolant will gradually drop to the ambient temperature. For example, the engine control unit can obtain the water temperature information of the engine through a water temperature sensor.

[0122] The ambient temperature information of the vehicle is used to indicate the ambient temperature around the vehicle, which can affect the viscosity of the engine oil and the fluidity of the coolant, and further affect the calibration of the fuel evaporation and injection system. For example, the engine control unit can obtain the ambient temperature information of the vehicle through the temperature sensor of the vehicle.

[0123] The battery capacity information of the vehicle is used to indicate the remaining capacity of the battery, which can affect the working efficiency of the starter. When the engine is stopped, if the electrical loads on the vehicle (such as lights, audio systems, etc.) continue to consume electricity, the capacity of the battery will gradually decrease. Exemplarily, the engine control unit can obtain the battery capacity information of the vehicle through the power sensor corresponding to the battery.

[0124] The transmission oil temperature information is used to indicate the temperature of the transmission oil in the transmission, which can affect the starting efficiency of the engine. For example, the transmission control unit can obtain the transmission oil temperature information through the transmission oil temperature sensor, send the transmission oil temperature information to the bus, and the engine control unit can obtain the transmission oil temperature information from the bus.

[0125] In a possible implementation scheme, the engine control unit can set a basic engine speed value according to the missing tooth position when the engine is stopped; thereafter, if the temperature of the engine coolant, the ambient temperature around the vehicle, the battery capacity, and the temperature of the transmission oil are low, the engine control unit can increase the upward stroke speed; conversely, if the temperature of the engine coolant, the ambient temperature around the vehicle, the battery capacity, and the temperature of the transmission oil are high, the engine control unit can reduce the upward stroke speed; thereafter, the engine control unit can predict the ignition timing and injection timing according to the missing tooth position when the engine is stopped, and then predict the upward stroke speed.

[0126] The embodiments of the present application provide specific contents that the above-mentioned vehicle operating condition information may include. The engine control unit in the vehicle control system may comprehensively consider information such as the missing tooth position, ambient temperature, coolant, battery capacity, etc. at the time of engine shutdown, and predict the upward speed when the engine is restarted to ensure that the engine can start quickly and improve the starting performance of the engine.

[0127] The present application also provides a vehicle control system, which can be Figure 1 The vehicle control system 110 in the system shown includes an engine control unit and a transmission control unit;

[0128] An engine control unit, used to predict the engine restart speed information based on the vehicle operating condition information when the engine automatic start-stop system is working and the engine is automatically shut down; the vehicle operating condition information includes at least the engine state information, and the engine restart speed information is used to indicate the engine speed increase process after the engine is restarted;

[0129] The transmission control unit is used to determine a first oil pressure according to the upward impact speed information; the first oil pressure is used to make the output torque of the clutch not greater than the perceptible minimum impact transmission torque;

[0130] A transmission control unit, used for controlling the clutch to be in a semi-clutch state through an electronic pump according to a first oil pressure when the engine automatic start-stop system is working and the engine is restarted;

[0131] A transmission control unit is used to obtain a second oil pressure; the second oil pressure is the oil pressure output by the mechanical pump after the engine is restarted;

[0132] The gearbox control unit is used to control the clutch to be in a clamped state through a mechanical pump when the second oil pressure is equal to the first oil pressure.

[0133] Regarding the specific manner in which the vehicle control system, the engine control unit and the transmission control unit perform operations in the above-mentioned embodiment have been described in detail in the embodiment of the method, and will not be elaborated here.

[0134] The clutch control method shown in the above embodiment of the present application can be applied to a traditional automatic transmission with a torque converter. In the related art, when the start-stop function is enabled and the engine is restarted after shutdown, the start of the engine easily causes a sense of impact on the entire vehicle. In view of the above-mentioned impact problem, based on any one or more of the above embodiments, the embodiment of the present application proposes a control method for starting the start-stop function of the AT / CVT transmission. First, according to the operating condition information after shutdown, the engine ignition target speed is obtained. According to the target speed, the speed of the transmission input shaft is monitored. When the input shaft speed exceeds a certain value, the clutch is controlled. The present application accurately controls the pressure of the clutch during the startup process to maintain it in a semi-engaged state, so that the engine startup impact will not be transmitted to the transmission system through the torque converter and the clutch, which can significantly reduce the impact on the transmission system during the engine startup process and reduce the sense of movement of the entire vehicle during startup.

[0135] The structure corresponding to the above control method is as follows Figure 4 As shown, the output shaft of the engine is connected to the input shaft of the torque converter, and the input shaft of the torque converter is connected to the mechanical pump. After the engine is started, it can drive the operation of the torque converter and the mechanical pump. The solenoid valve is set in the main oil circuit of the gearbox, and can switch the electronic pump or the mechanical pump to provide oil pressure to the clutch. The above control method involves engine starting speed control, torque converter clutch control, electronic oil pump control, solenoid valve oil pressure and steering valve control, clutch control, etc. The specific process is described in detail as follows:

[0136] 1) After the engine is stopped, the start time and start up speed are estimated according to the current stop position, and are used as the target time and target speed for the next start and input to the transmission controller:

[0137] When the engine is stopped, the engine control unit estimates the engine's starting speed and starting duration based on the missing tooth position, phase relationship, ambient temperature, water temperature, battery capacity and other information at the time of engine shutdown, and transmits it to the transmission control unit through the vehicle network as the starting target speed and target time.

[0138] 2) When the engine starts, the transmission control unit controls the electronic start-stop pump to provide a preset first gear clutch pressure based on the estimated engine start time and the upward speed:

[0139] The transmission control unit estimates the engine output torque rising process based on the above-mentioned starting target speed and target time. Specifically, according to the characteristics of the torque converter, the torque loss of the turbine and pump wheel during the hydraulic transmission process, the torque consumed by the mechanical pump during pressure building, etc., are finally transmitted to the clutch end through the output shaft of the torque converter during the upward rush of the input shaft of the torque converter driven by the engine.

[0140] After that, the torque transmitted by the output shaft of the torque converter is subtracted from the perceptible minimum impact transmission torque to obtain a difference value. Among them, the perceptible minimum impact transmission torque is obtained in advance by the developers in experiments and tests according to different models and different transmission systems.

[0141] When the above difference is negative or zero, the electronic pump provides a first numerical oil pressure; the first numerical oil pressure can be a larger pressure value in the pressure range supported by the electronic pump; when the above difference is positive, the electronic pump controls a synovial pressure through a second numerical oil pressure according to the difference, so that the torque transmitted through the output shaft of the torque converter, after passing through the synovial of the clutch, is not greater than the above minimum impact transmission torque.

[0142] 3) After the engine starts to surge, the mechanical pump is driven to build up oil pressure. The gearbox control unit controls the reversing valve inside the solenoid valve to achieve oil pressure reversal from the electronic pump to the mechanical pump:

[0143] During the engine upstroke process, the maximum value of the above-estimated start-up upstroke speed is set as the engine upstroke target speed. The transmission control unit drives the mechanical oil pump to establish the oil pressure of the transmission according to the engine upstroke target speed. When the oil pressure reaches the oil pressure provided by the electronic pump, the reversing valve inside the solenoid valve is controlled to move and reverse, ensuring a smooth transition of the oil pressure from the electronic pump providing the first gear clutch pressure to the mechanical pump providing the first gear clutch pressure.

[0144] 4) During the solenoid valve reversal process, the pressure of the first gear clutch is accurately controlled. During the engine speed surge, the first gear clutch is in a sliding film state. After the speed exceeds the predicted surge speed, the clutch is tightened:

[0145] When the speed of the mechanical pump follows the speed of the input shaft, the switching part of the solenoid valve is pre-filled with part of the oil pressure to ensure smooth and fast switching.

[0146] When the first-gear clutch is controlled by sliding film control and the engine speed exceeds or reaches the maximum speed of overshoot, the oil pressure of the first-gear clutch is controlled to press and fit the first-gear clutch to ensure smooth starting response of the vehicle.

[0147] That is to say, during the engine start-up process, when the driver steps on the accelerator to start, the clutch engagement pressure is calculated according to the upward speed, and the clutch is controlled to a certain sliding film control. When the oil pressure established by the mechanical pump exceeds this engagement pressure, the reversing valve of the solenoid valve switches to the main oil pressure of the mechanical pump, and the clutch clamping oil pressure is increased through the control of the solenoid valve. In summary, this method can significantly reduce the impact of the vehicle on the transmission system when it is restarted after the engine is shut down, thereby reducing the feeling of movement of the vehicle when starting.

[0148] Please refer to Figure 5 , which shows a block diagram of a clutch control device provided by an exemplary embodiment of the present application. The clutch control device can be implemented as all or part of a computer device by hardware or a combination of hardware and software to achieve the above Figure 2 All or part of the steps in the embodiments shown. Figure 5 As shown, the device comprises:

[0149] The speed prediction module 501 is used to predict the speed information of the engine restart according to the vehicle operating condition information when the engine automatic start-stop system is working and the engine is automatically shut down; the vehicle operating condition information at least includes the state information of the engine, and the speed information of the engine restart is used to indicate the speed increase process after the engine restarts;

[0150] The oil pressure determination module 502 is used to determine a first oil pressure according to the impulse speed information; the first oil pressure is used to make the output torque of the clutch not greater than the perceptible minimum impact transmission torque;

[0151] The first control module 503 is used to control the clutch to be in a semi-clutch state through an electronic pump according to the first oil pressure when the engine automatic start-stop system is working and the engine is restarted;

[0152] The oil pressure acquisition module 504 is used to acquire the second oil pressure; the second oil pressure is the oil pressure output by the mechanical pump after the engine is restarted;

[0153] The second control module 505 is used to control the clutch to be in a tightening state through a mechanical pump when the second oil pressure is equal to the first oil pressure.

[0154] In a possible implementation, the oil pressure determination module 502 is used to determine the output torque of the clutch according to the upward stroke speed information;

[0155] The oil pressure determination module 502 is configured to determine a first oil pressure according to the output torque of the clutch.

[0156] In a possible implementation, the oil pressure determination module 502 is used to obtain a torque difference value; the torque difference value is used to indicate the difference between the output torque of the clutch and the perceptible minimum impact transmission torque;

[0157] The oil pressure determination module 502 is configured to determine a first oil pressure according to the torque difference.

[0158] In a possible implementation, the device further includes:

[0159] An electronic pump starting module is used to start the electronic pump when the engine automatic start-stop system is working and the engine is automatically shut down;

[0160] A mechanical pump starting module is used to start the mechanical pump when the engine automatic start-stop system is working and the engine is restarted;

[0161] The electronic pump shutoff module is used to shut off the electronic pump when the second oil pressure is equal to the first oil pressure.

[0162] In one possible implementation, the engine status information indication includes the missing tooth position information of the engine and the water temperature information of the engine; the vehicle operating condition information also includes the ambient temperature information of the vehicle, the battery capacity of the vehicle and the oil temperature information of the transmission.

[0163] One point that needs to be explained is that the device provided in the above embodiment only uses the division of the above-mentioned functional modules as an example to implement its functions. In actual applications, the above-mentioned functions can be assigned to different functional modules according to actual needs, that is, the content structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0164] Regarding the device in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method; the technical effects achieved by each module performing operations are the same as those in the embodiment of the method, and will not be elaborated here.

[0165] Please refer to Figure 6, which shows a schematic diagram of the structure of a computer device provided by an exemplary embodiment of the present application. The computer device 600 includes a central processing unit (CPU) 601, a system memory 604 including a random access memory (RAM) 602 and a read-only memory (ROM) 603, and a system bus 605 connecting the system memory 604 and the central processing unit 601. The computer device 600 also includes a basic input / output system (I / O system) 606 that helps transmit information between various devices in the computer, and a large-capacity storage device 607 for storing an operating system 613, application programs 614 and other program modules 615.

[0166] The basic input / output system 606 includes a display 608 for displaying information and an input device 609 such as a mouse and a keyboard for user inputting information. The display 608 and the input device 609 are connected to the central processing unit 601 through an input / output controller 610 connected to the system bus 605. The basic input / output system 606 may also include an input / output controller 610 for receiving and processing inputs from a plurality of other devices such as a keyboard, a mouse, or an electronic stylus. Similarly, the input / output controller 610 also provides output to a display screen, a printer, or other types of output devices.

[0167] The mass storage device 607 is connected to the central processing unit 601 through a mass storage controller (not shown) connected to the system bus 605. The mass storage device 607 and its associated computer readable media provide non-volatile storage for the computer device 600. That is, the mass storage device 607 may include a computer readable medium (not shown) such as a hard disk or a CD-ROM (Compact Disc Read-Only Memory) drive.

[0168] Without loss of generality, computer readable media may include computer storage media and communication media. Computer storage media include volatile and non-volatile, removable and non-removable media implemented by any method or technology for storing information such as computer readable instructions, data structures, program modules or other data. Computer storage media include RAM (Random Access Memory), ROM (Read-Only Memory), EPROM (Erasable Programmable Read-Only Memory), EEPROM (Electrically Erasable Programmable Read-Only Memory), flash memory or other solid-state storage technologies, CD-ROM, DVD (Digital Video Disc) or other optical storage, cassettes, magnetic tapes, disk storage or other magnetic storage devices. Of course, those skilled in the art will appreciate that computer storage media are not limited to the above. The above-mentioned system memory 604 and mass storage device 607 can be collectively referred to as memory.

[0169] The computer device 600 can be connected to the Internet or other network devices through a network interface unit 611 connected to the system bus 605 .

[0170] The memory also includes one or more programs, one or more programs are stored in the memory, and the central processing unit 601 implements the one or more programs by executing the one or more programs. Figure 2 All or part of the steps in the method shown.

[0171] In an exemplary embodiment, a chip is also provided. The chip includes a programmable logic circuit and / or program instructions. When the chip runs on a computer device, it is used to implement all or part of the steps of the method shown in the above embodiments of the present application.

[0172] In an exemplary embodiment, a computer program product is also provided, the computer program product includes computer instructions, the computer instructions are stored in a computer-readable storage medium. The processor of the computer device reads the computer instructions from the computer-readable storage medium, and the processor reads and executes the computer instructions from the computer-readable storage medium to implement all or part of the steps of the method shown in the above-mentioned various embodiments of the present application.

[0173] In an exemplary embodiment, a computer-readable storage medium is also provided, in which a computer program is stored. The computer program is loaded and executed by a processor to implement all or part of the steps of the method shown in the above-mentioned embodiments of the present application.

[0174] A person skilled in the art will understand that all or part of the steps to implement the above embodiments may be accomplished by hardware or by instructing related hardware through a program. The above program may be stored in a computer-readable storage medium. The above storage medium may be a read-only memory, a disk or an optical disk, etc.

[0175] Those skilled in the art should be aware that in one or more of the above examples, the functions described in the embodiments of the present application can be implemented with hardware, software, firmware, or any combination thereof. When implemented using software, these functions can be stored in a computer-readable medium or transmitted as one or more instructions or codes on a computer-readable medium. Computer-readable media include computer storage media and communication media, wherein the communication media include any media that facilitates the transmission of a computer program from one place to another. The storage medium can be any available medium that a general or special-purpose computer can access.

[0176] The above are only optional embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A clutch control method, characterized in that: The method is implemented by a vehicle having an automatic engine start-stop system, and the method includes: When the engine automatic start-stop system is working and the engine is automatically shut down, predicting the engine restart speed information based on the vehicle operating condition information; the vehicle operating condition information at least includes the state information of the engine, and the engine restart speed information is used to indicate the engine speed increase process after the engine is restarted; Determining a first oil pressure according to the impulse speed information; the first oil pressure is used to ensure that the output torque of the clutch is not greater than the perceptible minimum impact transmission torque; When the engine automatic start-stop system is working and the engine is restarted, the clutch is controlled to be in a semi-clutch state by the electronic pump according to the first oil pressure; Acquiring a second oil pressure; the second oil pressure is the oil pressure output by the mechanical pump after the engine is restarted; When the second oil pressure is equal to the first oil pressure, the clutch is controlled to be in a clamping state by the mechanical pump.

2. The method according to claim 1, characterized in that The determining the first oil pressure according to the upward thrust speed information includes: determining the output torque of the clutch according to the overshoot speed information; The first oil pressure is determined according to the output torque of the clutch.

3. The method according to claim 2, characterized in that The determining the first oil pressure according to the output torque of the clutch comprises: Acquiring a torque difference value; the torque difference value is used to indicate the difference between the output torque of the clutch and the perceptible minimum impact transmission torque; The first oil pressure is determined according to the torque difference.

4. The method according to any one of claims 1 to 3, characterized in that: The method further comprises: When the engine automatic start-stop system is working and the engine is automatically shut down, starting the electronic pump; When the engine automatic start-stop system is working and the engine is restarted, starting the mechanical pump; When the second oil pressure is equal to the first oil pressure, the electronic pump is turned off.

5. The method according to any one of claims 1 to 3, characterized in that: The engine status information indication includes missing tooth position information of the engine and water temperature information of the engine; the vehicle operating condition information also includes ambient temperature information of the vehicle, battery capacity of the vehicle and oil temperature information of the transmission.

6. A vehicle control system, characterized in that: The system includes an engine control unit and a transmission control unit; The engine control unit is used to predict the engine restart speed information according to the vehicle operating condition information when the engine automatic start-stop system is working and the engine is automatically shut down; The vehicle operating condition information includes at least the state information of the engine, and the overshoot speed information is used to indicate the rising process of the speed of the engine after restarting; The transmission control unit is used to determine a first oil pressure according to the upward impact speed information; the first oil pressure is used to make the output torque of the clutch not greater than the perceptible minimum impact transmission torque; The transmission control unit is used to control the clutch to be in a semi-clutch state through the electronic pump according to the first oil pressure when the engine automatic start-stop system is working and the engine is restarted; The transmission control unit is used to obtain a second oil pressure; the second oil pressure is the oil pressure output by the mechanical pump after the engine is restarted; The transmission control unit is used to control the clutch to be in a tightening state through the mechanical pump when the second oil pressure is equal to the first oil pressure.

7. A clutch control device, characterized in that: The device comprises: A speed prediction module, used for predicting the speed information of the engine restarting according to the vehicle operating condition information when the engine automatic start-stop system is working and the engine is automatically shut down; the vehicle operating condition information at least includes the state information of the engine, and the speed information of the engine restarting is used to indicate the speed increase process after the engine restarts; An oil pressure determination module, configured to determine a first oil pressure according to the impulse speed information; the first oil pressure is configured to ensure that the output torque of the clutch is not greater than a perceptible minimum impact transmission torque; a first control module, configured to control the clutch to be in a semi-clutch state through the electronic pump according to the first oil pressure when the engine automatic start-stop system is working and the engine is restarted; An oil pressure acquisition module, used for acquiring a second oil pressure; the second oil pressure is the oil pressure output by the mechanical pump after the engine is restarted; The second control module is used to control the clutch to be in a clamping state through the mechanical pump when the second oil pressure is equal to the first oil pressure.

8. A computer device, characterized in that: The computer device includes a processor and a memory, wherein the memory stores at least one computer instruction, and the at least one computer instruction is loaded and executed by the processor to implement the clutch control method according to any one of claims 1 to 5.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores at least one computer instruction, and the computer instruction is loaded and executed by the processor to implement the clutch control method as described in any one of claims 1 to 5.

10. A computer program product, characterized in that The computer program product includes computer instructions, which are stored in a computer-readable storage medium; the computer instructions are read and executed by a processor of a computer device to implement the clutch control method as described in any one of claims 1 to 5.

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