CN114962627A

CN114962627A - Self-learning method and device for friction coefficient of clutch, transmission and storage medium

Info

Publication number: CN114962627A
Application number: CN202210601158.9A
Authority: CN
Inventors: 孙飞; 朱桂庆; 曹龙
Original assignee: FAW Group Corp
Current assignee: FAW Group Corp
Priority date: 2022-05-30
Filing date: 2022-05-30
Publication date: 2022-08-30
Anticipated expiration: 2042-05-30
Also published as: CN114962627B

Abstract

The embodiment of the invention discloses a friction coefficient self-learning method and device of a clutch, a transmission and a storage medium. The method comprises the following steps: detecting whether a self-learning start condition is satisfied in response to a vehicle shift request; if the self-learning starting condition is met, gear shifting control is carried out based on a self-learning control mode, and engine torque information and clutch pressure information within a preset self-learning duration are recorded; a target friction coefficient is determined based on the engine torque information and the clutch pressure information, and an original friction coefficient is updated based on the target friction coefficient. Through the technical scheme of the embodiment of the invention, the self-learning of the friction coefficient can be realized under the condition of large sliding friction difference of vehicle gear shifting, so that the more accurate control of the torque of the clutch can be realized.

Description

Self-learning method and device for friction coefficient of clutch, transmission and storage medium

Technical Field

The embodiment of the invention relates to vehicle technology, in particular to a friction coefficient self-learning method and device of a clutch, a transmission and a storage medium.

Background

With the rapid development of vehicle technology, people seek higher and higher driving comfort for vehicles. Vehicles using wet dual clutch transmissions use clutches primarily as the torque transmitting components. The key to controlling the dual-clutch transmission is to accurately control the torque of the clutch, so that the friction coefficient of the dual-clutch transmission needs to be accurately determined, and the more accurately the friction coefficient is determined, the more accurately the torque control of the clutch is.

Generally, the friction coefficient of the clutch is determined mainly by means of testing on a rack, a test result is used as the friction coefficient of a standard clutch and applied to a vehicle, and the friction coefficient can be continuously learned by self in the actual vehicle control process to update the friction coefficient. However, the current self-learning method can only learn the friction coefficient of the clutch under a small sliding friction difference, and the friction coefficient of the clutch under a large sliding friction difference cannot be well self-learned. Therefore, a self-learning method of friction coefficient under large slip is urgently needed.

Disclosure of Invention

The embodiment of the invention provides a friction coefficient self-learning method and device of a clutch, a transmission and a storage medium, so as to realize the self-learning of the friction coefficient of the clutch under large slip friction.

According to an aspect of the present invention, there is provided a friction coefficient self-learning method of a clutch, including:

detecting whether a self-learning start condition is satisfied in response to a vehicle shift request;

if the self-learning starting condition is met, gear shifting control is carried out based on a self-learning control mode, and engine torque information and clutch pressure information within a preset self-learning duration are recorded;

a target friction coefficient is determined based on the engine torque information and the clutch pressure information, and an original friction coefficient is updated based on the target friction coefficient.

According to another aspect of the present invention, there is provided a friction coefficient self-learning apparatus of a clutch, including:

self-learning detection means for detecting whether a self-learning start condition is satisfied in response to a vehicle shift request;

the self-learning control device is used for carrying out gear shifting control based on a self-learning control mode and recording engine torque information and clutch pressure information in a preset self-learning duration if the self-learning starting condition is met;

and the friction coefficient updating device is used for determining a target friction coefficient based on the engine torque information and the clutch pressure information and updating the original friction coefficient based on the target friction coefficient.

According to another aspect of the present invention, there is provided a dual clutch transmission comprising: two sets of clutches and a controller;

wherein the controller is adapted to implement a method of friction coefficient self-learning for a clutch according to any embodiment of the invention.

According to another aspect of the present invention, there is provided a computer readable storage medium storing computer instructions for causing a processor to implement a method for friction coefficient self-learning of a clutch according to any embodiment of the present invention when executed.

According to the technical scheme of the embodiment of the invention, whether the self-learning starting condition is met or not is detected by responding to the vehicle gear shifting request; if the self-learning starting condition is met, gear shifting control is carried out based on a self-learning control mode, and engine torque information and clutch pressure information within a preset self-learning duration are recorded; the target friction coefficient is determined based on the engine torque information and the clutch pressure information, and the original friction coefficient is updated based on the target friction coefficient, so that the friction coefficient can be learned by self under the condition of large slip friction difference of vehicle gear shifting, and the clutch torque can be controlled more accurately.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a flowchart illustrating a method for self-learning a friction coefficient of a clutch according to an embodiment of the present invention;

FIG. 2 is a schematic diagram illustrating the variation of clutch pressure and speed, for example, during a power upshift in accordance with an embodiment of the present invention;

FIG. 3 is a flowchart illustrating a method for self-learning a friction coefficient of a clutch according to a second embodiment of the present invention;

fig. 4 is a schematic structural diagram of a friction coefficient self-learning device of a clutch according to a third embodiment of the present invention.

Fig. 5 is a schematic structural diagram of a dual clutch transmission according to a fourth embodiment of the present invention.

Detailed Description

In order to make the technical solutions of the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the invention described herein are capable of operation in sequences other than those illustrated or described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

Example one

Fig. 1 is a flowchart of a method for self-learning a friction coefficient of a clutch according to an embodiment of the present invention, which may be applied to the self-learning of a friction coefficient under such a large slip during a gear shift of a vehicle. The large slip friction difference may refer to a condition that a difference between rotational speeds of the clutch master and the clutch slave is greater than a preset rotational speed difference, for example: the difference between the rotation speeds of the main clutch plate and the driven plate of the clutch is between 100 and 200. The method may be performed by a clutch coefficient of friction self-learning device, which may be implemented in hardware and/or software, which may be integrated into a controller in a dual clutch transmission. As shown in fig. 1, the method specifically includes the following steps:

and S110, responding to the vehicle gear shifting request, and detecting whether a self-learning starting condition is met.

The self-learning starting condition may refer to a condition which is preset and used for representing the self-learning allowable friction coefficient.

In particular, a large slip is often present during the shift timing of a vehicle having a dual clutch transmission. When the vehicle needs to shift gears, a vehicle shift request may be generated. A controller in the dual clutch transmission may detect whether a self-learning start condition is currently satisfied based on current vehicle state information when the vehicle shift request is detected. If the self-learning starting condition is met, the controller can start self-learning of the friction coefficient; if the self-learning start condition is not satisfied, the next vehicle shift request may be waited for to perform the self-learning operation of the coefficient of friction at the next vehicle shift.

For example, the "self-learning start condition" in S110 may include: the vehicle gear shifting request is a power gear-up request or a power gear-down request, the vehicle is not in a starting stage, the vehicle gear shifting request is non-coaxial gear shifting, the oil temperature of the transmission is within a preset oil temperature range, and the water temperature of the engine is within a preset water temperature range.

The non-coaxial gear shifting can mean that the 1, 3 and 5 gear slots are arranged on one shaft, the 2 and 4 gear slots are arranged on the other shaft, and the gear shifting is performed in a gear sequential change mode instead of a gear jump mode in the gear shifting process, for example, the vehicle gear is 3 gear at the present moment, the gear shifting can be performed to 2 gear or 4 gear, and the gear shifting is not performed to 1 gear or 5 gear. Specifically, if the current vehicle state information meets all the self-learning starting conditions, the condition of large sliding friction can occur in the subsequent gear shifting adjusting process, and self-learning is started; if the current vehicle state information does not meet any one of the self-learning starting conditions, the condition that the large slip-friction difference does not occur in the subsequent gear shifting adjusting process is indicated, and self-learning is not performed, so that the condition that the large slip-friction difference does not occur in the subsequent gear shifting adjusting process is avoided, and the self-learned friction coefficient is obtained under the condition that the large slip-friction difference does not occur.

And S120, if the self-learning starting condition is met, performing gear shifting control based on a self-learning control mode, and recording engine torque information and clutch pressure information in a preset self-learning duration.

The preset self-learning time length can be preset, and the time length of the friction coefficient can be learned by self. Fig. 2 shows a schematic diagram of the clutch pressure and speed variation process, for example, in a power upshift. For example, the preset self-learning period may be a period between time t2 and time t3 in fig. 2.

Specifically, if the current vehicle state information meets the self-learning start condition, the gear shifting control can be performed based on the self-learning control mode, and the engine torque information and the clutch pressure information for determining the friction coefficient within the preset self-learning duration are recorded. For example, the high range clutch may be controlled to maintain its applied pressure constant during the period between t2 and t3 in FIG. 2, and the engine torque information and clutch pressure information may be recorded in preparation for a more accurate determination of the coefficient of friction.

And S130, determining a target friction coefficient based on the engine torque information and the clutch pressure information, and updating the original friction coefficient based on the target friction coefficient.

The friction coefficient calculation formula is mu-T/-n P, wherein mu is the friction coefficient of the clutch, T is the engine torque average value, n is the rotational speed difference, and P is the pressure applied by the clutch. Specifically, the controller determines a target friction coefficient through a friction coefficient calculation formula based on engine torque information and clutch pressure information, and updates the target friction coefficient and the corresponding original friction coefficient, so that the updated existing friction coefficient can be called when the friction coefficient is called next time, the called friction coefficient is the more accurate friction coefficient, and accurate control of the torque of the clutch is finally achieved.

According to the technical scheme of the embodiment of the invention, whether a self-learning starting condition is met is detected by responding to a vehicle gear shifting request; if the self-learning starting condition is met, gear shifting control is carried out based on a self-learning control mode, and engine torque information and clutch pressure information within a preset self-learning duration are recorded; the target friction coefficient is determined based on the engine torque information and the clutch pressure information, and the original friction coefficient is updated based on the target friction coefficient, so that the friction coefficient can be learned by self under the condition of large slip friction difference of vehicle gear shifting, and the clutch torque can be controlled more accurately.

Based on the above technical solution, the step S120 of performing shift control based on the self-learning control manner may include: controlling oil pressure to perform gear shift preparation and torque exchange based on a vehicle gear shift request; controlling the pressure of a target gear clutch corresponding to the vehicle gear shifting request to be kept unchanged within a preset self-learning duration after the torque exchange is finished; after the self-learning duration is preset at intervals, the pressure of a target gear clutch corresponding to the vehicle gear shifting request is controlled to shift and regulate the speed based on the original pressure control mode until the gear shifting is finished.

Here, controlling the oil pressure may mean controlling the oil pressure in an oil pressure range that can be used for shifting. The torque exchange may refer to exchanging torque corresponding to the high clutch pressure with torque corresponding to the low clutch pressure, for example, torque change at stages t1-t2 in fig. 2.

Specifically, referring to fig. 2, a power upshift is taken as an example. During the period t1-t2, the controller controls oil pressure to perform shift preparation and torque exchange based on the vehicle shift request, wherein the torque exchange may be to decrease the low clutch pressure to the high clutch pressure value at time t1 and increase the high clutch pressure beyond the low clutch pressure value at time t 1. During the preset self-learning time period after the torque exchange is finished, namely the stages from t2 to t3 in the stage of fig. 2, the controller controls the pressure of the target gear clutch corresponding to the vehicle gear shifting request to be kept unchanged, namely the pressure of the high gear clutch in the stage from t2 to t3 in the stage of fig. 2 is kept unchanged, so that the rotation speed difference between the rotation speed of the engine and the rotation speed of the target gear clutch is kept unchanged. After the preset self-learning time duration is set at intervals, namely the stage t3-t4 in fig. 2, the controller controls the pressure of the target gear clutch corresponding to the vehicle gear shifting request to perform gear shifting speed regulation based on the original clutch pressure control mode, namely the controller controls the pressure of the high gear clutch to perform gear up speed regulation according to the original clutch pressure change mode until the gear shifting is completed.

For example, "controlling the pressure of the target gear clutch corresponding to the vehicle shift request to remain unchanged for a preset self-learning period after the end of the torque exchange" may include: if the vehicle gear shifting request is a power gear-up request, controlling the pressure of the high-gear clutch to be kept unchanged within a preset self-learning duration after the torque exchange is finished; and if the vehicle gear shifting request is a power downshift request, controlling the pressure of the low-gear clutch to be kept unchanged within a preset self-learning duration after the torque exchange is finished.

Specifically, the controller controls the clutch pressure for a preset self-learning period after the end of the torque interchange based on the type of vehicle shift request. If the vehicle gear shifting request is detected to be a power gear shifting request, the controller controls the pressure of the high-gear clutch to be kept unchanged within a preset self-learning duration after the torque exchange is finished; if the vehicle gear shifting request is detected to be a power downshift request, the controller controls the pressure of the low-gear clutch to be kept unchanged within the preset self-learning duration after the torque exchange is finished, so that the working condition change of gears in the driving process can be responded, and the self-learning of the friction coefficient can be more accurately carried out.

Example two

Fig. 3 is a flowchart of a friction coefficient self-learning method for a clutch according to a second embodiment of the present invention, which is based on the above embodiments, and adds the steps of determining a target friction coefficient based on engine torque information and clutch pressure information, and updating an original friction coefficient based on the target friction coefficient, "during a vehicle shift, if it is detected that a self-learning update condition is not satisfied, exiting a self-learning control operation, and performing a shift control based on an original control manner. Wherein explanations of the same or corresponding terms as those of the above-described embodiments of the present invention are omitted. As shown in fig. 3, the method specifically includes the following steps:

s210, responding to the vehicle gear shifting request, and detecting whether a self-learning starting condition is met.

And S220, if the self-learning starting condition is met, performing gear shifting control based on a self-learning control mode, and recording engine torque information and clutch pressure information in a preset self-learning duration.

And S230, determining a target friction coefficient based on the engine torque information and the clutch pressure information, and updating the original friction coefficient based on the target friction coefficient.

And S240, in the vehicle gear shifting process, if the condition that the self-learning updating condition is not met is detected, the self-learning control operation is quitted, and gear shifting control is carried out based on the original control mode.

Wherein the self-learning update condition may refer to a condition characterizing that an update of an existing friction coefficient is allowed. Specifically, during the vehicle gear shifting process, that is, in the time period before t4 in fig. 2, if it is detected that the vehicle state information does not satisfy the self-learning update condition, the self-learning control operation is exited, the original friction coefficient is prevented from being updated, and normal gear shifting control is performed based on the original control mode, so that the accuracy of self-learning can be further ensured. It should be noted that after the gear shifting is finished, if the self-learning updating condition is met, the original friction coefficient is updated based on the target friction coefficient, so that the accuracy of updating the friction coefficient can be further ensured.

For example, the "self-learning update condition" in S240 may include: the change value of the accelerator opening is smaller than a preset change threshold value, the torque fluctuation of an engine is smaller than a preset torque fluctuation threshold value, the fluctuation of the rotation speed difference of the engine and a transmission in a speed regulation stage is smaller than a preset rotation speed difference fluctuation threshold value, the acceleration of the rotation speed of an output shaft of the transmission is smaller than a preset acceleration, the rotation speed of the engine is in a preset rotation speed range, the torque of the engine is in a preset torque range and the surface temperature of a clutch is in a preset temperature range.

Specifically, if the current vehicle state information does not satisfy any of the self-learning update conditions, it indicates that updating of the existing friction coefficient is not allowed currently, and at this time, the self-learning operation may be exited, and the gear shift control may be performed according to the original control mode until the gear shift is completed.

For example, the step S240 of exiting the self-learning control operation and performing the shift control based on the original control manner if it is detected that the self-learning update condition is not satisfied may include: if the self-learning updating condition is not met before the torque exchange is finished, controlling the pressure of a target gear clutch corresponding to the vehicle gear shifting request to perform gear shifting and speed regulating directly on the basis of the original pressure control mode after the torque exchange is finished; if the self-learning updating condition is not met within the preset self-learning duration after the torque exchange is finished, interrupting the self-learning control operation, controlling the pressure of a target gear clutch corresponding to the vehicle gear shifting request to carry out gear shifting speed regulation based on the original pressure control mode, and deleting the information recorded within the preset self-learning duration; and if the self-learning updating condition is not met after the preset self-learning duration is spaced, continuously controlling the pressure of the target gear clutch corresponding to the vehicle gear shifting request to shift gears and regulate the speed based on the original pressure control mode, and deleting the information recorded in the preset self-learning duration.

Specifically, if it is detected that the self-learning update condition is not satisfied before the torque exchange is finished, for example, in a time period before t2 in fig. 2, the pressure of the target gear clutch corresponding to the vehicle shift request is controlled to perform shift speed regulation directly after the torque exchange is finished based on the original clutch pressure control mode, for example, normal shift control is performed after directly skipping the stage t2-t3 in fig. 2. If the self-learning updating condition is not met in the preset self-learning time period after the torque exchange is finished, for example, in the time period between t2 and t3 in fig. 2, the self-learning control operation is interrupted, the pressure of the target gear clutch corresponding to the vehicle gear shifting request is controlled to perform gear shifting speed regulation based on the original clutch pressure control mode, the engine torque information and the clutch pressure information recorded in the preset self-learning time period are deleted, for example, in the mode that t3 is reset to be the current stage in fig. 2, the stages from t2 to t3 are interrupted, speed regulation is directly performed, and data are not recorded. If the self-learning updating condition is detected not to be met after the preset self-learning time period is spaced, for example, in a time period after t3 in fig. 2, the pressure of the target gear clutch corresponding to the vehicle gear shifting request is controlled to perform gear shifting speed regulation continuously based on the original clutch pressure control mode, and the engine torque information and the clutch pressure information recorded in the preset self-learning time period are deleted, for example, the following control can be performed normally in fig. 2, and no data is recorded.

According to the technical scheme of the embodiment of the invention, in the vehicle gear shifting process, if the condition that the self-learning updating condition is not met is detected, the self-learning control operation is quitted, and the normal gear shifting control is carried out based on the original control mode, so that the accuracy of self-learning can be further ensured, and the method is compatible with the original control mode.

EXAMPLE III

Fig. 4 is a schematic structural diagram of a friction coefficient self-learning device of a clutch according to a third embodiment of the present invention. As shown in fig. 4, the apparatus specifically includes: self-learning detection device 310, self-learning control device 320, and friction coefficient updating device 330.

Wherein the self-learning detecting means 310 is adapted to detect whether a self-learning start condition is fulfilled in response to a vehicle gear shift request. And the self-learning control device 320 is used for carrying out gear shifting control based on a self-learning control mode if self-learning starting conditions are met, and recording engine torque information and clutch pressure information in a preset self-learning duration. And a friction coefficient updating means 330 for determining a target friction coefficient based on the engine torque information and the clutch pressure information, and updating the original friction coefficient based on the target friction coefficient.

Optionally, the self-learning start condition comprises: the vehicle gear shifting request is a power gear-up request or a power gear-down request, the vehicle is not in a starting stage, the vehicle gear shifting request is non-coaxial gear shifting, the oil temperature of the transmission is within a preset oil temperature range, and the water temperature of the engine is within a preset water temperature range.

Optionally, the self-learning control device 320 comprises:

a torque exchange control unit for controlling oil pressure to perform gear shift preparation and torque exchange based on a vehicle gear shift request;

the pressure control unit is used for controlling the pressure of a target gear clutch corresponding to the vehicle gear shifting request to be kept unchanged within a preset self-learning duration after the torque exchange is finished;

and the gear shifting and speed regulating unit is used for controlling the pressure of the target gear clutch corresponding to the vehicle gear shifting request to perform gear shifting and speed regulating based on the original pressure control mode after the self-learning duration is preset at intervals until the gear shifting is finished.

Optionally, the pressure control unit is specifically configured to: if the vehicle gear shifting request is a power gear-up request, controlling the pressure of the high-gear clutch to be kept unchanged within a preset self-learning duration after the torque exchange is finished; and if the vehicle gear shifting request is a power downshift request, controlling the pressure of the low-gear clutch to be kept unchanged within a preset self-learning duration after the torque exchange is finished.

Optionally, the apparatus further comprises:

and the self-learning exit module is used for exiting self-learning control operation and carrying out gear shifting control based on the original control mode if the self-learning update condition is not met in the vehicle gear shifting process.

Optionally, the self-learning update condition comprises: the change value of the accelerator opening is smaller than a preset change threshold value, the torque fluctuation of the engine is smaller than a preset torque fluctuation threshold value, the speed difference fluctuation of the engine and the transmission in a speed regulation stage is smaller than a preset speed difference fluctuation threshold value, the rotating speed acceleration of an output shaft of the transmission is smaller than a preset acceleration, the rotating speed of the engine is in a preset rotating speed range, the torque of the engine is in a preset torque range and the surface temperature of the clutch is in a preset temperature range.

Optionally, the self-learning exit module is specifically configured to:

if the self-learning updating condition is not met before the torque exchange is finished, controlling the pressure of a target gear clutch corresponding to the vehicle gear shifting request to perform gear shifting and speed regulating directly on the basis of the original pressure control mode after the torque exchange is finished; if the self-learning updating condition is not met within the preset self-learning duration after the torque exchange is finished, interrupting the self-learning control operation, controlling the pressure of a target gear clutch corresponding to the vehicle gear shifting request to shift and regulate the speed based on the original pressure control mode, and deleting the information recorded within the preset self-learning duration; and if the self-learning updating condition is not met after the preset self-learning duration is separated, continuously controlling the pressure of the target gear clutch corresponding to the vehicle gear shifting request to shift gears and regulate the speed based on the original pressure control mode, and deleting the information recorded in the preset self-learning duration.

Example four

Fig. 5 is a schematic structural diagram of a dual clutch transmission according to a fourth embodiment of the present invention. The components shown herein, their connections and relationships, and their functions, are meant to be examples only, and are not intended to limit implementations of the inventions described and/or claimed herein.

As shown in fig. 5, dual clutch transmission 400 may include two sets of clutches, a first clutch 410 and a second clutch 420, respectively, and a controller 430. Wherein the controller 430 is configured to implement a method of self-learning a coefficient of friction of a clutch as provided in any of the embodiments of the present invention.

According to the dual-clutch transmission provided by the embodiment of the invention, the controller can detect whether a self-learning starting condition is met or not by responding to a vehicle gear shifting request; if the self-learning starting condition is met, gear shifting control is carried out based on a self-learning control mode, and engine torque information and clutch pressure information within a preset self-learning duration are recorded; the target friction coefficient is determined based on the engine torque information and the clutch pressure information, and the original friction coefficient is updated based on the target friction coefficient, so that the friction coefficient can be learned by self under the condition of large slip friction difference of vehicle gear shifting, and the clutch torque can be controlled more accurately.

EXAMPLE five

The present embodiments provide a computer-readable storage medium having stored thereon a computer program which, when executed by a processor, implements a method of self-learning a coefficient of friction of a clutch as provided in any of the embodiments of the invention.

From the above description of the embodiments, it is obvious for those skilled in the art that the present invention can be implemented by software and necessary general hardware, and certainly, can also be implemented by hardware, but the former is a better embodiment in many cases. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which may be stored in a computer-readable storage medium, such as a floppy disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a FLASH Memory (FLASH), a hard disk or an optical disk of a computer, and includes instructions for enabling a computer device (which may be a personal computer, a server, or a network device) to execute the method for self-learning the friction coefficient of the clutch according to the embodiments of the present invention.

It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. Those skilled in the art will appreciate that the present invention is not limited to the particular embodiments described herein, and that various obvious changes, rearrangements and substitutions will now be apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A method for self-learning a friction coefficient of a clutch, comprising:

2. The method of claim 1, wherein the self-learning start condition comprises:

the vehicle gear shifting request is a power gear-up request or a power gear-down request, the vehicle is not in a starting stage, the vehicle gear shifting request is non-coaxial gear shifting, the oil temperature of the transmission is within a preset oil temperature range, and the water temperature of the engine is within a preset water temperature range.

3. The method of claim 1, wherein the performing shift control based on a self-learning control scheme comprises:

controlling oil pressure to perform gear shift preparation and torque exchange based on the vehicle gear shift request;

controlling the pressure of a target gear clutch corresponding to the vehicle gear shifting request to be kept unchanged within a preset self-learning duration after the torque exchange is finished;

and after the preset self-learning duration is spaced, controlling the pressure of a target gear clutch corresponding to the vehicle gear shifting request to perform gear shifting speed regulation based on the original pressure control mode until the gear shifting is finished.

4. The method of claim 3, wherein controlling the pressure of the target gear clutch corresponding to the vehicle shift request to remain constant for a preset self-learning duration after the end of the torque interchange comprises:

if the vehicle gear shifting request is a power gear-up request, controlling the pressure of the high-gear clutch to be kept unchanged within a preset self-learning duration after the torque exchange is finished;

and if the vehicle gear shifting request is a power downshift request, controlling the pressure of the low-gear clutch to be kept unchanged within a preset self-learning duration after the torque exchange is finished.

5. The method according to any one of claims 1-4, further comprising:

and in the vehicle gear shifting process, if the self-learning updating condition is not met, the self-learning control operation is quitted, and gear shifting control is carried out based on the original control mode.

6. The method of claim 5, wherein the self-learning update condition comprises:

the change value of the accelerator opening is smaller than a preset change threshold value, the torque fluctuation of the engine is smaller than a preset torque fluctuation threshold value, the speed difference fluctuation of the engine and the transmission in a speed regulation stage is smaller than a preset speed difference fluctuation threshold value, the rotating speed acceleration of an output shaft of the transmission is smaller than a preset acceleration, the rotating speed of the engine is in a preset rotating speed range, the torque of the engine is in a preset torque range and the surface temperature of the clutch is in a preset temperature range.

7. The method of claim 5, wherein if it is detected that the self-learning update condition is not satisfied, exiting the self-learning control operation and performing the shift control based on the original control manner comprises:

if the self-learning updating condition is not met before the torque exchange is finished, controlling the pressure of a target gear clutch corresponding to the vehicle gear shifting request to perform gear shifting and speed regulating directly on the basis of the original pressure control mode after the torque exchange is finished;

if the self-learning updating condition is not met within the preset self-learning duration after the torque exchange is finished, interrupting the self-learning control operation, controlling the pressure of a target gear clutch corresponding to the vehicle gear shifting request to carry out gear shifting speed regulation based on the original pressure control mode, and deleting the information recorded within the preset self-learning duration;

and if the self-learning updating condition is not met after the preset self-learning duration is spaced, continuously controlling the pressure of the target gear clutch corresponding to the vehicle gear shifting request to shift gears and regulate the speed based on the original pressure control mode, and deleting the information recorded in the preset self-learning duration.

8. A friction coefficient self-learning device for a clutch, comprising:

9. A dual clutch transmission, comprising: two sets of clutches and a controller;

wherein the controller is used for realizing the friction coefficient self-learning method of the clutch as set forth in any one of claims 1-7.

10. A computer readable storage medium storing computer instructions for causing a processor to perform a method for friction coefficient self-learning of a clutch according to any one of claims 1-7 when executed.