Clutch torque determination method, device, vehicle and storage medium

Abstract

The application provides a clutch torque determination method and device, a vehicle and a storage medium. The method is applied to the technical field of vehicles and includes the following steps: acquiring a hysteresis coefficient of a hydraulic system, a friction coefficient of a clutch and a rotational speed difference between two ends of the clutch at different temperatures; acquiring a torque value corresponding to the clutch at different pressures based on the rotational speed difference when the rotational speed difference meets a preset stable condition, and performing curve fitting to obtain a pressure-torque reference curve of the clutch; correcting the pressure-torque reference curve based on the hysteresis coefficient and the friction coefficient to obtain an adaptive pressure-torque curve of the clutch, and then determining the torque of the clutch at different temperatures. The method can obtain the pressure-torque curve based on the high-torque interval and the low-torque interval, so that the corresponding pressure request can be output according to different working conditions and temperature conditions when the engine outputs a certain torque, thereby improving the transmission accuracy of the clutch torque.

Description

Technical Field

[0001] This application relates to the field of vehicle technology, and more specifically, to a method, apparatus, vehicle, and storage medium for determining clutch torque in the field of vehicle technology. Background Technology

[0002] As an important component of the vehicle's power system, the clutch is an assembly directly connected to the engine. Located between the engine and the transmission, it is used to transmit the torque stored on the engine flywheel to the transmission, ensuring that the vehicle delivers the appropriate amount of driving force and torque to the drive wheels under different driving conditions, thereby ensuring the safe operation of the vehicle.

[0003] However, the clutch is controlled by a hydraulic system, which varies greatly with changes in environment, transmission oil temperature, and vehicle condition. For example, the lag of the hydraulic system is more pronounced at low temperatures. As a result, it is impossible to guarantee the power and smoothness of the vehicle under different operating conditions, which urgently needs to be addressed. Summary of the Invention

[0004] This application provides a clutch torque determination method, device, vehicle, and storage medium. The method can improve the transmission accuracy of clutch torque by using pressure-torque curves obtained from high torque and low torque ranges to output corresponding pressure requests based on different operating conditions and temperature conditions when the engine outputs a certain torque.

[0005] In a first aspect, a method for determining clutch torque is provided. This method includes: acquiring the hysteresis coefficient of a hydraulic system, the friction coefficient of the clutch, and the speed difference between the input and output ends of the clutch at different temperatures; when the speed difference meets a preset stability condition, acquiring the torque value of the clutch under different pressures based on the speed difference, obtaining multiple pressure-torque curves for different torque ranges, and performing curve fitting on the multiple pressure-torque curves to obtain a pressure-torque reference curve for the clutch at the current temperature; and based on the pressure-torque reference curve at the current temperature, correcting the pressure-torque reference curve at the current temperature according to the hysteresis coefficient of the hydraulic system and the friction coefficient of the clutch at different temperatures, obtaining multiple adaptive pressure-torque curves for the clutch at different temperatures, and determining the torque of the clutch at different temperatures based on the multiple adaptive pressure-torque curves.

[0006] By using the above technical solution, based on the pressure-torque curves obtained in the high torque range and low torque range, when the engine outputs a certain torque, it can output the corresponding pressure request according to different operating conditions and temperature conditions, thereby improving the transmission accuracy of clutch torque.

[0007] In conjunction with the first aspect, in some possible implementations, before performing curve fitting on the multiple pressure-torque curves to obtain the pressure-torque reference curve of the clutch at the current temperature, the method further includes: determining whether the torque value meets the preset curve fitting conditions; if the torque value does not meet the preset curve fitting conditions, then continuing to obtain the pressure-torque curves of the clutch in different torque ranges based on the speed difference.

[0008] By using the above technical solution, the pressure-torque reference curve of the clutch can be obtained based on a stable torque value, which can improve the output accuracy of the clutch.

[0009] In conjunction with the first aspect and the above implementation methods, in some possible implementation methods, determining whether the torque value satisfies the preset curve fitting condition includes: determining preset critical torque values ​​for the first torque range and the second torque range of the clutch, and collecting multiple torque values ​​output by the engine, wherein the torque values ​​in the first torque range are all greater than the preset critical torque value, and the torque values ​​in the second torque range are all less than the preset critical torque value; if the multiple torque values ​​are all between the maximum torque value in the first torque range and the preset critical torque value, then the multiple torque values ​​are determined to satisfy the first pressure-torque curve fitting condition; if the multiple torque values ​​are all less than the preset critical torque value, then the multiple torque values ​​are determined to satisfy the second pressure-torque curve fitting condition.

[0010] By using the above technical solutions, it is possible to judge whether multiple pressure-torque curves meet the fitting conditions of high torque curves and low torque curves, thereby improving the accuracy of clutch curve fitting.

[0011] Combining the first aspect and the above-described implementation methods, in some possible implementation methods, the step of curve fitting the torque value to obtain the pressure-torque reference curve of the clutch at the current temperature includes: curve fitting the torque value of the first torque range based on the least squares method to obtain the first pressure-torque curve of the clutch; learning the system operating parameters using a preset deep learning model, and curve fitting the torque value of the second torque range using the preset deep learning model to obtain the second pressure-torque curve of the clutch; smoothing the connection between the first pressure-torque curve and the second pressure-torque curve to obtain the pressure-torque reference curve of the clutch at the current temperature.

[0012] By fitting the high torque curve and low torque curve of the clutch to the above technical solution, the pressure-torque reference curve of the clutch is obtained, so as to determine the pressure of the clutch at different temperatures and thus output the corresponding torque value.

[0013] In combination with the first aspect and the above implementation methods, in some possible implementation methods, before obtaining multiple adaptive pressure-torque curves of the clutch at different temperatures, the method further includes: constructing a prediction model for the hysteresis coefficient of the hydraulic system and the friction coefficient of the clutch at different temperatures; based on the pressure-torque reference curve at the current temperature, and according to the hysteresis coefficient of the hydraulic system, the friction coefficient of the clutch, and the operating conditions of the vehicle, using the prediction model to correct the hysteresis coefficient and the friction coefficient, so as to correct the pressure value corresponding to the torque of the clutch at different temperatures according to the corrected hysteresis coefficient and friction coefficient; and obtaining multiple adaptive pressure-torque curves of the clutch at different temperatures according to the corrected pressure value.

[0014] By modifying the pressure-torque reference curve, the influence of the transmission oil temperature box and clutch steel plate temperature on the clutch pressure-torque reference curve is reduced, and finally, the adaptive pressure-torque curve of the clutch at different temperatures is obtained, thereby improving the output accuracy of the clutch torque.

[0015] In combination with the first aspect and the above implementation methods, in some possible implementation methods, the step of obtaining the torque value of the clutch under different pressures based on the speed difference when the speed difference satisfies the preset stability condition includes: obtaining the torque value of the clutch and the torque value of the engine; determining whether the torque value of the clutch and the torque value of the engine are the same; if the torque value of the clutch and the torque value of the engine are the same, then determining that the speed difference satisfies the preset stability condition, and obtaining the torque value of the clutch under different pressures based on the speed difference.

[0016] By using the above technical solution, and by judging the stability of the clutch speed difference, when the speed difference meets the preset stability condition, the torque value of the clutch under different pressures is obtained under the speed difference, so as to prevent the torque value from deviating.

[0017] Secondly, a clutch torque determination device is provided, comprising: an acquisition module for acquiring the hysteresis coefficient of a hydraulic system, the friction coefficient of the clutch, and the speed difference between the input and output ends of the clutch at different temperatures; a fitting module for acquiring the torque value of the clutch under different pressures based on the speed difference when the speed difference meets a preset stability condition, and performing curve fitting on the torque value to obtain a pressure-torque reference curve of the clutch at the current temperature; and a determination module for correcting the pressure-torque reference curve at the current temperature based on the pressure-torque reference curve at the current temperature according to the hysteresis coefficient of the hydraulic system and the friction coefficient of the clutch at different temperatures, obtaining multiple adaptive pressure-torque curves of the clutch, and determining the torque of the clutch at different temperatures based on the multiple adaptive pressure-torque curves.

[0018] In conjunction with the second aspect, in some possible implementations, before performing curve fitting on the torque value to obtain the pressure-torque reference curve of the clutch at the current temperature, the fitting module further includes: a judgment unit, used to judge whether the torque value meets the preset curve fitting conditions; and a first acquisition unit, used to continue acquiring the pressure-torque curves of the clutch in different torque ranges based on the speed difference if the torque value does not meet the preset curve fitting conditions.

[0019] In conjunction with the second aspect and the above implementation methods, in some possible implementation methods, the judgment unit includes: a determining subunit, configured to determine preset critical torque values ​​for the first torque range and the second torque range of the clutch, and to collect multiple torque values ​​output by the engine, wherein the torque values ​​in the first torque range are all greater than the preset critical torque value, and the torque values ​​in the second torque range are all less than the preset critical torque value; a first determining subunit, configured to determine that the multiple torque values ​​satisfy the first pressure-torque curve fitting condition if the multiple torque values ​​are all between the maximum torque value in the first torque range and the preset critical torque value; and a second determining subunit, configured to determine that the multiple torque values ​​satisfy the second pressure-torque curve fitting condition if the multiple torque values ​​are all less than the preset critical torque value.

[0020] In combination with the second aspect and the above implementation methods, in some possible implementation methods, the fitting module includes: a first fitting unit, used to perform curve fitting on the torque values ​​of the first torque range based on the least squares method to obtain a first pressure-torque curve of the clutch; a second fitting unit, used to learn the system operating parameters using a preset deep learning model, and to perform curve fitting on the torque values ​​of the second torque range using the preset deep learning model to obtain a second pressure-torque curve of the clutch; and a processing unit, used to smooth the connection between the first pressure-torque curve and the second pressure-torque curve to obtain a pressure-torque reference curve of the clutch at the current temperature.

[0021] In conjunction with the second aspect and the above implementation methods, in some possible implementation methods, before obtaining multiple adaptive pressure-torque curves of the clutch at different temperatures, the determining module further includes: a construction unit, used to construct a prediction model of the hysteresis coefficient of the hydraulic system and the friction coefficient of the clutch at different temperatures; a correction unit, used to correct the hysteresis coefficient and the friction coefficient based on the pressure-torque reference curve at the current temperature, according to the hysteresis coefficient of the hydraulic system, the friction coefficient of the clutch, and the operating condition of the vehicle, using the prediction model, so as to correct the pressure value corresponding to the torque of the clutch at different temperatures according to the corrected hysteresis coefficient and friction coefficient; and a second acquisition unit, used to obtain multiple adaptive pressure-torque curves of the clutch at different temperatures according to the corrected pressure value.

[0022] In combination with the second aspect and the above implementation methods, in some possible implementation methods, the fitting module includes: a third acquisition unit, used to acquire the torque value of the clutch and the torque value of the engine; a fourth acquisition unit, used to determine whether the torque value of the clutch and the torque value of the engine are the same; if the torque value of the clutch and the torque value of the engine are the same, then it is determined that the speed difference satisfies the preset stability condition, and the torque value of the clutch under different pressures is acquired based on the speed difference.

[0023] Thirdly, a vehicle is provided, including: a clutch torque determination method as described in the above embodiments.

[0024] Fourthly, a computer-readable storage medium is provided that stores computer program code, which, when executed on a computer, causes the computer to perform the methods described in the first aspect or any possible implementation thereof. Attached Figure Description

[0025] Figure 1This is a schematic flowchart of a clutch torque determination method provided in an embodiment of this application;

[0026] Figure 2 This is a schematic diagram of a curve fitting process provided in one embodiment of this application;

[0027] Figure 3 A block diagram illustrating a clutch torque determining device provided in an embodiment of this application;

[0028] Figure 4 This is a schematic diagram of the vehicle structure provided in an embodiment of this application. Detailed Implementation

[0029] The technical solutions in this application will be clearly and thoroughly described below with reference to the accompanying drawings. In the description of the embodiments of this application, unless otherwise stated, " / " means "or," for example, A / B can mean A or B. "And / or" in the text is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Furthermore, in the description of the embodiments of this application, "multiple" refers to two or more than two.

[0030] Hereinafter, the terms "first" and "second" are used for descriptive purposes only and should not be construed as implying or suggesting relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0031] Clutches are used in various transmissions (such as traditional AMT (Automated-Mechanical-Transmission), AT (Auto Transmission), DCT (Dual Clutch Transmission), hybrid technology in hybrid vehicles, and DHT (Dedicated-Loop Transmission). The clutch, a component that transmits torque between a hybrid transmission (such as a hybrid-specific transmission) and the engine, largely determines the drivability of the vehicle. Since the clutch is controlled by a hydraulic system, which is affected by the transmission temperature, exhibiting significant differences at different transmission oil temperatures—for example, noticeable lag at low temperatures—and changes in environment and vehicle condition can cause substantial variations in the output torque under the same clutch pressure. Using the same clutch torque at the same pressure under different conditions leads to deviations in the clutch's response to engine torque, making it difficult to guarantee the vehicle's power and smoothness under varying driving conditions. This application's embodiment improves the clutch torque transmission accuracy by using pressure-torque curves (PT curves) obtained in high and low torque ranges to output corresponding pressure requests based on different operating conditions and temperatures when the engine outputs a certain torque.

[0032] Figure 1 This is a schematic flowchart of a clutch torque determination method provided in an embodiment of this application.

[0033] For example, such as Figure 1 As shown, the method includes:

[0034] In step S101, the hysteresis coefficient of the hydraulic system, the friction coefficient of the clutch, and the speed difference between the input and output ends of the clutch are obtained at different temperatures.

[0035] Specifically, such as Figure 2 As shown, in order to improve the service life of the clutch and reduce the occurrence of failures, this application embodiment adopts a wet clutch. Because the torque transmitted by the clutch under the same pressure is different at different temperatures, it can be shown that the transmission accuracy of the clutch torque directly affects the performance of the whole vehicle. Therefore, this application embodiment further limits the transmission accuracy of the clutch torque, so that the vehicle can control the clutch to adaptively output the corresponding torque according to temperature and pressure in different driving environments and driving states.

[0036] Specifically, in this embodiment, in order to monitor the accuracy of the clutch's adaptive output torque under different temperatures and pressures, i.e., the accuracy of the clutch PT adaptation, firstly, it is necessary to obtain the vehicle's system operating parameters to determine the vehicle's stable state before the clutch enters the adaptive output torque state. For example, it is necessary to obtain the engine motor speed, engine coolant temperature, engine motor torque, and transmission oil temperature, and determine whether the engine motor speed, engine coolant temperature, engine motor torque, and transmission oil temperature are in a stable state, such as the state of the engine motor speed, engine coolant temperature, engine motor torque, and transmission oil temperature when the vehicle is traveling at a constant speed. Secondly, when the engine motor speed, engine coolant temperature, engine motor torque, and transmission oil temperature are in a stable state, the hysteresis coefficient of the hydraulic system, the friction coefficient of the clutch, and the speed difference between the clutch input end and output end are obtained at different oil temperatures, and it is monitored whether the speed difference of the clutch forms a stable speed difference, i.e., slip.

[0037] In step S102, when the speed difference meets the preset stability condition, the torque value of the clutch under different pressures based on the speed difference is obtained, and the torque value is curve fitted to obtain the pressure-torque reference curve of the clutch at the current temperature.

[0038] Optionally, in one embodiment of this application, when the speed difference meets a preset stability condition, obtaining the torque value of the clutch under different pressures based on the speed difference includes: obtaining the torque value of the clutch and the torque value of the engine; determining whether the torque value of the clutch and the torque value of the engine are the same; if the torque value of the clutch and the torque value of the engine are the same, then determining that the speed difference meets the preset stability condition, and obtaining the torque value of the clutch under different pressures based on the speed difference.

[0039] The preset stability conditions can be set by those skilled in the art based on the actual use of the clutch, or determined based on the results of a limited number of computer simulations, and are not specifically limited here.

[0040] Specifically, such as Figure 2As shown in this embodiment, firstly, the torque values ​​of the clutch and the engine are obtained, and it is determined whether the torque values ​​of the clutch and the engine are the same, that is, whether the input torque value of the engine and the output torque value of the clutch are the same. If the torque values ​​of the clutch and the engine are the same, it means that the acceleration of the clutch is 0, and the speed difference can be determined to be in a stable state, that is, the preset stability condition is met. Secondly, when the speed difference of the clutch meets the preset stability condition, it means that the net torque value of the engine and the load of the clutch have just reached a balance value. At the same time, it is monitored whether the torque values ​​of the clutch and the engine are stable. If the engine torque value and the clutch torque value are monitored to be stable within a certain range in the current cycle, it means that the engine torque value and the clutch torque value are in a stable state. At this time, the torque value of the clutch under different pressures is recorded, that is, the corresponding pressure-torque value.

[0041] It should be noted that since the stable speed difference is not exactly the same under different systems and structures, the speed difference of the clutch in the embodiments of this application is generally set between 30 rpm and 50 rpm.

[0042] Optionally, in one embodiment of this application, before performing curve fitting on the torque value to obtain the pressure-torque reference curve of the clutch at the current temperature, the method further includes: determining whether the torque value meets the preset curve fitting conditions; if the torque value does not meet the preset curve fitting conditions, then continuing to obtain the torque value corresponding to the clutch under different pressures based on the speed difference.

[0043] Optionally, in one embodiment of this application, determining whether the torque value meets the preset curve fitting condition includes: determining the preset critical torque values ​​of the first torque range and the second torque range of the clutch, and collecting multiple torque values ​​output by the engine, wherein the torque values ​​of the first torque range are all greater than the preset critical torque value, and the torque values ​​of the second torque range are all less than the preset critical torque value; if the multiple torque values ​​are all between the maximum torque value of the first torque range and the preset critical torque value, then the multiple torque values ​​are determined to meet the first pressure-torque curve fitting condition; if the multiple torque values ​​are all less than the preset critical torque value, then the multiple torque values ​​are determined to meet the second pressure-torque curve fitting condition.

[0044] The preset critical torque value can be set by those skilled in the art based on the hydraulic system and clutch structure. Preferably, the preset critical torque value used in this application embodiment is 20 Nm.

[0045] Specifically, in this embodiment, after obtaining the torque values ​​of the clutch under different pressures based on the speed difference, firstly, a preset critical torque value (e.g., 20 Nm) is determined for the first and second torque ranges of the clutch, and multiple torque values ​​output by the engine are collected. The torque values ​​in the first torque range are all greater than the preset critical torque value, and the torque values ​​in the second torque range are all less than the preset critical torque value. Secondly, after collecting the multiple torque values ​​output by the engine, the torque values ​​greater than the preset critical torque value are stored in the high torque memory (i.e., the first torque range), and the torque values ​​less than the preset critical torque value are stored in the low torque memory (i.e., the second torque range). Then, within the first torque range, multiple torque values ​​output by the engine are collected every 10 Nm. The engine torque value is the torque value of the pressure-torque curve. When the engine torque value is greater than the preset critical torque value, the speed difference between the two ends of the clutch is maintained at 30 rpm, and the clutch pressure value is obtained through the pressure sensor. At this time, the clutch pressure value is the pressure value of the pressure-torque curve. At the same time, the speed difference between the two ends of the clutch is maintained at 30 rpm. The test is repeated until the maximum torque value that the engine and clutch can transmit is collected. Points greater than the maximum torque value are filtered out. If multiple torque values ​​output by the engine are all between the maximum torque value of the first torque range and the preset critical torque value, it is determined that multiple torque values ​​meet the first pressure-torque curve fitting condition. If multiple torque values ​​are all less than the preset critical torque value, it is determined that multiple torque values ​​meet the second pressure-torque curve fitting condition.

[0046] Furthermore, if the torque value does not meet the preset curve fitting conditions, the torque value corresponding to the clutch under different pressures based on the speed difference is obtained until the torque value meets the preset curve fitting conditions.

[0047] Optionally, in one embodiment of this application, curve fitting is performed on the torque value to obtain the pressure-torque reference curve of the clutch at the current temperature, including: curve fitting of the torque value in the first torque range based on the least squares method to obtain the first pressure-torque curve of the clutch; learning the system operating parameters using a preset deep learning model, and curve fitting of the torque value in the second torque range using the preset deep learning model to obtain the second pressure-torque curve of the clutch; smoothing the connection between the first pressure-torque curve and the second pressure-torque curve to obtain the pressure-torque reference curve of the clutch at the current temperature.

[0048] The preset deep learning model can be selected by those skilled in the art based on actual fitting needs; for example, no specific limitation is made here.

[0049] Specifically, if the torque value of the first torque range in this embodiment satisfies the first pressure-torque curve fitting condition, then the torque value of the first torque range is curve-fitted based on the least squares method to obtain the first pressure-torque curve of the clutch, that is, a pressure-torque of more than 20 Nm is fitted; if the torque value of the second torque range in this embodiment satisfies the second pressure-torque curve fitting condition, then the torque value of the second torque range is curve-fitted through a preset deep learning model to obtain the second pressure-torque curve of the clutch, that is, a pressure-torque of less than 20 Nm is fitted.

[0050] It should be noted that, since the nonlinear characteristics of wet clutches are very obvious in the low-pressure range, this embodiment of the application needs to construct a preset deep learning model for the low-pressure range at room temperature, such as a BP deep learning model, and collect system operating parameters, such as clutch temperature, clutch input and output speeds, engine torque and clutch torque, as input values ​​of the preset deep learning model. Based on a large amount of data collection, the torque value in the second torque range is curve-fitted through the preset deep learning model to obtain the second pressure-torque curve of the clutch. Thus, the pressure-torque curve of the clutch at the current temperature is obtained based on the first pressure-torque curve and the second pressure-torque curve of the clutch.

[0051] Furthermore, in this embodiment of the application, in order to prevent the pressure-torque curve of the clutch at the current temperature from abruptly changing at 20 Nm, it is necessary to smooth the connection between the first pressure-torque curve and the second pressure-torque curve under normal temperature conditions. For example, the connection between the first pressure-torque curve and the second pressure-torque curve can be smoothed using MATLAB, and the confidence factor of the pressure-torque curve can be changed. The confidence factor will gradually increase with the number of times the clutch is learned and the mileage. The pressure-torque curve under normal temperature is fitted and used as the reference curve, that is, the pressure-torque reference curve of the clutch at the current temperature.

[0052] In step S103, based on the pressure-torque reference curve at the current temperature, the pressure-torque reference curve at the current temperature is corrected according to the hysteresis coefficient of the hydraulic system and the friction coefficient of the clutch at different temperatures, so as to obtain multiple adaptive pressure-torque curves of the clutch at different temperatures, and the torque of the clutch at different temperatures is determined based on the multiple adaptive pressure-torque curves.

[0053] Optionally, in one embodiment of this application, before obtaining multiple adaptive pressure-torque curves of the clutch at different temperatures, the method further includes: constructing a predictive model of the hysteresis coefficient of the hydraulic system and the friction coefficient of the clutch at different temperatures; based on the pressure-torque reference curve at the current temperature, and according to the hysteresis coefficient of the hydraulic system, the friction coefficient of the clutch, and the operating conditions of the vehicle, using the predictive model to correct the hysteresis coefficient and the friction coefficient, so as to correct the pressure value corresponding to the torque of the clutch at different temperatures according to the corrected hysteresis coefficient and the friction coefficient; and obtaining multiple adaptive pressure-torque curves of the clutch at different temperatures according to the corrected pressure value.

[0054] The preset prediction model can be selected by those skilled in the art based on actual fitting needs; for example, no specific limitation is made here.

[0055] Specifically, since the transmission oil temperature and clutch plate temperature significantly affect the clutch pressure-torque reference curve, the influence of transmission oil temperature on the pressure-torque reference curve is mainly reflected in the hydraulic system response, with the hysteresis coefficient as the influencing factor. The clutch plate temperature mainly affects the clutch friction coefficient. Therefore, after obtaining the clutch pressure-torque reference curve, this embodiment needs to construct a predictive model for the hysteresis coefficient of the hydraulic system and the friction coefficient of the clutch under different temperatures of transmission oil and clutch plate. By collecting various input parameters such as the stable speed difference between the two ends of the clutch at different temperatures, engine speed and torque, clutch plate temperature, and transmission oil temperature, and taking the stable speed difference as the target, the predictive model is used to correct the hysteresis coefficient and friction coefficient. Based on the corrected hysteresis coefficient and friction coefficient, the pressure value corresponding to the clutch torque at different temperatures is corrected. Thus, multiple adaptive pressure-torque curves of the clutch at different temperatures are obtained based on the corrected pressure value. Therefore, when the engine outputs multiple torque values ​​to the input end of the clutch, the clutch can output corresponding torque according to different operating conditions. Since this torque is achieved by establishing pressure through the clutch, the adaptive pressure-torque curve can transmit accurate clutch torque.

[0056] It should be noted that if one end of the clutch is connected to a motor, the motor's torque is more accurate than the engine's torque value. In this case, the motor's torque value should be used instead of the engine's torque value.

[0057] In summary, the embodiments of this application, through the relevant discussion of the clutch torque determination method, can achieve the following effective effects:

[0058] (1) The clutch torque determination method of this application divides the fitting of the PT curve into fitting of the high torque range (first torque range) and fitting of the low torque range (second torque range) according to its physical characteristics, which solves the problem of inaccurate PT curve of the whole vehicle under different working conditions, especially in the low torque range. The PT adaptive method solves the problem of vehicle vibration and power performance caused by clutch pressure following.

[0059] (2) Since the PT curve is greatly affected by the temperature of the transmission oil and the temperature of the clutch steel plate, this application uses the model prediction method to correct the PT by using the coefficients corresponding to different parameters for the response of the transmission oil temperature to the hydraulic delay, and to correct the friction coefficient for the temperature of the clutch steel plate. The PT curve under all working conditions can be obtained. While adapting to the vehicle environment, it can also adapt to different temperatures and different clutch wear throughout the entire life cycle of the vehicle, making the calculation more accurate.

[0060] In summary, the clutch torque determination method of this application obtains the hysteresis coefficient, friction coefficient, and speed difference between the two ends of the clutch at different temperatures. When the speed difference meets a preset stability condition, it obtains the torque value of the clutch under different pressures based on the speed difference, and performs curve fitting to obtain the clutch pressure-torque reference curve. Based on a prediction model, it corrects the hysteresis coefficient and friction coefficient, and then corrects the pressure-torque reference curve according to the corrected hysteresis coefficient and friction coefficient to obtain the clutch adaptive pressure-torque curve, thereby determining the clutch torque at different temperatures. This method can use the pressure-torque curves obtained in the high torque range and low torque range to output corresponding pressure requests according to different operating conditions and temperature conditions when the engine outputs a certain torque, thereby improving the transmission accuracy of clutch torque.

[0061] Figure 3 This is a block diagram of a clutch torque determining device provided in an embodiment of this application.

[0062] For example, such as Figure 3 As shown, the device 10 may include: an acquisition module 100, a fitting module 200, and a determination module 300.

[0063] The acquisition module 100 is used to acquire the hysteresis coefficient of the hydraulic system, the friction coefficient of the clutch, and the speed difference between the clutch input end and output end at different temperatures.

[0064] The fitting module 200 is used to acquire the torque values ​​of the clutch under different pressures based on the speed difference when the speed difference meets the preset stability conditions, and to perform curve fitting on the torque values ​​to obtain the pressure-torque reference curve of the clutch at the current temperature; and

[0065] The determination module 300 is used to modify the pressure-torque reference curve at the current temperature based on the pressure-torque reference curve at the current temperature, according to the hysteresis coefficient of the hydraulic system and the friction coefficient of the clutch at different temperatures, to obtain multiple adaptive pressure-torque curves of the clutch, and to determine the torque of the clutch at different temperatures based on the multiple adaptive pressure-torque curves.

[0066] Optionally, in one embodiment of this application, before performing curve fitting on the torque value to obtain the pressure-torque reference curve of the clutch at the current temperature, the fitting module 200 further includes:

[0067] The judgment unit is used to determine whether the torque value meets the preset curve fitting conditions.

[0068] The first acquisition unit is used to continue acquiring the pressure-torque curves of the clutch in different torque ranges based on the speed difference if the torque value does not meet the preset curve fitting conditions.

[0069] Optionally, in one embodiment of this application, the determining unit includes:

[0070] A determination subunit is used to determine the preset critical torque values ​​of the first torque range and the second torque range of the clutch, and to collect multiple torque values ​​output by the engine, wherein the torque values ​​of the first torque range are all greater than the preset critical torque values, and the torque values ​​of the second torque range are all less than the preset critical torque values.

[0071] The first determination subunit is used to determine that if multiple torque values ​​are all between the maximum torque value in the first torque range and the preset critical torque value, then the multiple torque values ​​satisfy the first pressure-torque curve fitting condition.

[0072] The second determination subunit is used to determine that if multiple torque values ​​are all less than a preset critical torque value, then the multiple torque values ​​satisfy the second pressure-torque curve fitting condition.

[0073] Optionally, in one embodiment of this application, the fitting module 200 includes:

[0074] The first fitting unit is used to perform curve fitting on the torque value of the first torque range based on the least squares method to obtain the first pressure-torque curve of the clutch.

[0075] The second fitting unit is used to learn the system operating parameters using a preset deep learning model, and to perform curve fitting on the torque value in the second torque range using the preset deep learning model to obtain the second pressure-torque curve of the clutch.

[0076] The processing unit is used to smooth the connection between the first pressure-torque curve and the second pressure-torque curve to obtain the pressure-torque reference curve of the clutch at the current temperature.

[0077] Optionally, in one embodiment of this application, before obtaining multiple adaptive pressure-torque curves of the clutch at different temperatures, the determination module 300 further includes:

[0078] The building blocks are used to construct predictive models of the hysteresis coefficient of a hydraulic system and the friction coefficient of a clutch at different temperatures.

[0079] The correction unit is used to correct the hysteresis coefficient and friction coefficient based on the pressure-torque reference curve at the current temperature, according to the hysteresis coefficient of the hydraulic system, the friction coefficient of the clutch, and the operating conditions of the vehicle, using a predictive model, so as to correct the pressure value corresponding to the torque of the clutch at different temperatures based on the corrected hysteresis coefficient and friction coefficient.

[0080] The second acquisition unit is used to obtain multiple adaptive pressure-torque curves of the clutch at different temperatures based on the corrected pressure value.

[0081] Optionally, in one embodiment of this application, the fitting module 200 includes:

[0082] The third acquisition unit is used to acquire the torque value of the clutch and the torque value of the engine;

[0083] The fourth acquisition unit is used to determine whether the torque value of the clutch and the torque value of the engine are the same. If the torque value of the clutch and the torque value of the engine are the same, it is determined that the speed difference meets the preset stability condition, and the torque value of the clutch under different pressures is obtained based on the speed difference.

[0084] In summary, the clutch torque determination device of this application acquires the hysteresis coefficient of the hydraulic system, the friction coefficient of the clutch, and the speed difference between the two ends of the clutch at different temperatures. When the speed difference meets a preset stability condition, it acquires the torque value of the clutch under different pressures based on the speed difference, and performs curve fitting to obtain the clutch pressure-torque reference curve. Based on a prediction model, it corrects the hysteresis coefficient and friction coefficient, and then corrects the pressure-torque reference curve based on the corrected hysteresis coefficient and friction coefficient to obtain the clutch adaptive pressure-torque curve, thereby determining the clutch torque at different temperatures. This method can output corresponding pressure requests based on different operating conditions and temperatures when the engine outputs a certain torque, based on the pressure-torque curves obtained in the high torque range and low torque range, thereby improving the transmission accuracy of the clutch torque.

[0085] Figure 4 This is a schematic diagram of the structure of a vehicle provided in an embodiment of this application.

[0086] It should be understood that the methods described above can be applied to... Figure 4In the vehicle with the structure shown.

[0087] Furthermore, this application also protects an apparatus that may include a memory 401 and a processor 402, wherein the memory 401 stores executable program code, and the processor 402 is used to call and execute the executable program code to perform the thermal imaging display method of the fuel cell stack system provided in this application.

[0088] Furthermore, the device also includes a communication interface 403 for communication between the memory 401 and the processor 402.

[0089] This embodiment can divide the device into functional modules based on the above method example. For example, each module can correspond to a separate function, or two or more functions can be integrated into one processing module. The integrated module can be implemented in hardware. It should be noted that the module division in this embodiment is illustrative and only represents one logical functional division. In actual implementation, there may be other division methods.

[0090] When the functional modules are divided according to their respective functions, the device may also include a data acquisition module, a determination module, and a control module. It should be noted that all relevant content regarding the steps involved in the above method embodiments can be referenced to the functional descriptions of the corresponding functional modules, and will not be repeated here.

[0091] It should be understood that the device provided in this embodiment is used to perform the above-described clutch torque determination method, and therefore can achieve the same effect as the above-described implementation method.

[0092] When using integrated units, the device may include a processing module and a storage module. When applied to an automobile, the processing module can be used to control and manage the vehicle's movements. The storage module can be used to support the vehicle in executing program code, etc.

[0093] The processing module may be a processor 402 or a controller, which may implement or execute various exemplary logic blocks, modules, and circuits as disclosed herein. The processor 402 may also be a combination of computing functions, such as a combination of one or more microprocessors, a combination of digital signal processing (DSP) and microprocessors, etc., and the storage module may be a memory 401.

[0094] In addition, the device provided in the embodiments of this application may specifically be a chip, component or module. The chip may include a connected processor 402 and a memory 401. The memory 401 is used to store instructions. When the processor calls and executes the instructions, the chip can execute the thermal imaging display method of the fuel cell stack system provided in the above embodiments.

[0095] This embodiment also provides a computer-readable storage medium storing computer program code. When the computer program code is run on a computer, the computer executes the above-described related method steps to implement the thermal imaging display method for a fuel cell stack system provided in the above embodiment.

[0096] This embodiment also provides a computer program product that, when run on a computer, causes the computer to perform the aforementioned related steps to implement a thermal imaging display method for an electric stack system provided in the above embodiment.

[0097] In this embodiment, the device, computer-readable storage medium, computer program product, or chip are all used to execute the corresponding methods provided above. Therefore, the beneficial effects they can achieve can be referred to the beneficial effects in the corresponding methods provided above, and will not be repeated here.

[0098] Through the above description of the embodiments, those skilled in the art will understand that, for the sake of convenience and brevity, only the division of the above functional modules is used as an example. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0099] In the embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of modules or 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 device, 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; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0100] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for determining clutch torque, characterized in that, The method includes: Obtain the hysteresis coefficient of the hydraulic system, the friction coefficient of the clutch, and the speed difference between the input and output ends of the clutch at different temperatures; When the speed difference meets a preset stability condition, the torque values ​​of the clutch under different pressures based on the speed difference are obtained, and the torque values ​​are curve-fitted to obtain the pressure-torque reference curve of the clutch at the current temperature; and Based on the pressure-torque reference curve at the current temperature, the pressure-torque reference curve at the current temperature is corrected according to the hysteresis coefficient of the hydraulic system and the friction coefficient of the clutch at different temperatures, so as to obtain multiple adaptive pressure-torque curves of the clutch at different temperatures, and the torque of the clutch at different temperatures is determined based on the multiple adaptive pressure-torque curves. The step of curve fitting the torque value to obtain the pressure-torque reference curve of the clutch at the current temperature includes: curve fitting the torque value in the first torque range based on the least squares method to obtain the first pressure-torque curve of the clutch; learning the system operating parameters using a preset deep learning model, and curve fitting the torque value in the second torque range using the preset deep learning model to obtain the second pressure-torque curve of the clutch; and smoothing the connection between the first pressure-torque curve and the second pressure-torque curve to obtain the pressure-torque reference curve of the clutch at the current temperature. Before obtaining multiple adaptive pressure-torque curves of the clutch at different temperatures, the method further includes: constructing a predictive model for the hysteresis coefficient of the hydraulic system and the friction coefficient of the clutch at different temperatures; based on the pressure-torque baseline curve at the current temperature, and according to the hysteresis coefficient of the hydraulic system, the friction coefficient of the clutch, and the vehicle's operating conditions, using the predictive model to correct the hysteresis coefficient and the friction coefficient, so as to correct the pressure value corresponding to the torque of the clutch at different temperatures according to the corrected hysteresis coefficient and friction coefficient; and obtaining multiple adaptive pressure-torque curves of the clutch at different temperatures based on the corrected pressure value.

2. The method according to claim 1, characterized in that, Before performing curve fitting on the torque value to obtain the pressure-torque reference curve of the clutch at the current temperature, the following steps are also included: Determine whether the torque value meets the preset curve fitting conditions; If the torque value does not meet the preset curve fitting conditions, then continue to obtain the torque value of the clutch under different pressures based on the speed difference.

3. The method according to claim 2, characterized in that, The step of determining whether the torque value meets the preset curve fitting conditions includes: Determine the preset critical torque values ​​for the first torque range and the second torque range of the clutch, and collect multiple torque values ​​output by the engine, wherein the torque values ​​in the first torque range are all greater than the preset critical torque values, and the torque values ​​in the second torque range are all less than the preset critical torque values. If all of the torque values ​​are between the maximum torque value in the first torque range and the preset critical torque value, then the torque values ​​are determined to satisfy the first pressure-torque curve fitting condition. If all of the multiple torque values ​​are less than the preset critical torque value, then the multiple torque values ​​are determined to satisfy the second pressure-torque curve fitting condition.

4. The method according to claim 1, characterized in that, When the speed difference meets a preset stability condition, obtaining the torque value of the clutch under different pressures based on the speed difference includes: Obtain the torque value of the clutch and the torque value of the engine; If the torque value of the clutch is the same as the torque value of the engine, then it is determined that the speed difference satisfies the preset stability condition, and the torque value of the clutch under different pressures based on the speed difference is obtained.

5. A clutch torque determining device, characterized in that, include: The acquisition module is used to acquire the hysteresis coefficient of the hydraulic system, the friction coefficient of the clutch, and the speed difference between the input and output ends of the clutch at different temperatures. The fitting module is used to obtain the torque value of the clutch under different pressures based on the speed difference when the speed difference meets the preset stability condition, and to perform curve fitting on the torque value to obtain the pressure-torque reference curve of the clutch at the current temperature. as well as The determination module is used to modify the pressure-torque reference curve at the current temperature based on the pressure-torque reference curve at the current temperature, according to the hysteresis coefficient of the hydraulic system and the friction coefficient of the clutch at different temperatures, to obtain multiple adaptive pressure-torque curves of the clutch, and to determine the torque of the clutch at different temperatures based on the multiple adaptive pressure-torque curves; The fitting module includes: a first fitting unit, used to perform curve fitting on the torque values ​​in the first torque range based on the least squares method to obtain a first pressure-torque curve of the clutch; a second fitting unit, used to learn the system operating parameters using a preset deep learning model, and to perform curve fitting on the torque values ​​in the second torque range using the preset deep learning model to obtain a second pressure-torque curve of the clutch; and a processing unit, used to smooth the connection between the first pressure-torque curve and the second pressure-torque curve to obtain a pressure-torque reference curve of the clutch at the current temperature. Before obtaining multiple adaptive pressure-torque curves of the clutch at different temperatures, the determining module further includes: a construction unit for constructing a predictive model of the hysteresis coefficient of the hydraulic system and the friction coefficient of the clutch at different temperatures; a correction unit for correcting the hysteresis coefficient and the friction coefficient based on the pressure-torque reference curve at the current temperature, according to the hysteresis coefficient of the hydraulic system, the friction coefficient of the clutch, and the operating conditions of the vehicle, using the predictive model, so as to correct the pressure value corresponding to the torque of the clutch at different temperatures according to the corrected hysteresis coefficient and friction coefficient; and a second acquisition unit for obtaining multiple adaptive pressure-torque curves of the clutch at different temperatures based on the corrected pressure value.

6. The apparatus according to claim 5, characterized in that, Before performing curve fitting on the torque value to obtain the pressure-torque reference curve of the clutch at the current temperature, the fitting module further includes: A judgment unit is used to determine whether the torque value meets the preset curve fitting conditions; The acquisition unit is used to acquire the torque value of the clutch under different pressures based on the speed difference if the torque value does not meet the preset curve fitting conditions.

7. A vehicle, characterized in that, The vehicle includes: a clutch torque determination method as described in any one of claims 1-4 above.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed, implements the method as described in any one of claims 1 to 4.

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