CN114818195A

CN114818195A - Clutch pressure self-learning method and device, vehicle-mounted terminal and medium

Info

Publication number: CN114818195A
Application number: CN202210498231.4A
Authority: CN
Inventors: 曹龙; 宁甲奎; 朱桂庆; 孙飞; 于天浩
Original assignee: FAW Group Corp
Current assignee: FAW Group Corp
Priority date: 2022-05-09
Filing date: 2022-05-09
Publication date: 2022-07-29

Abstract

The invention discloses a clutch pressure self-learning method and device, a vehicle-mounted terminal and a medium. The method comprises the following steps: acquiring current demand pressure and current actual pressure of a clutch; according to the prestored valve body project termination EOL data table, dividing the area by pressure, and determining the current pressure division area corresponding to the current required pressure; acquiring the stay time of the current required pressure in the current pressure division area; if the stay time meets the preset stay time threshold judgment condition, judging whether the clutch pressure self-learning is needed or not according to the current demand pressure and the current actual pressure; and controlling to carry out clutch pressure self-learning according to the judgment result. According to the embodiment of the application, the accuracy of clutch pressure self-learning is improved.

Description

Clutch pressure self-learning method and device, vehicle-mounted terminal and medium

Technical Field

The invention relates to the technical field of automatic control, in particular to a clutch pressure self-learning method and device, a vehicle-mounted terminal and a medium.

Background

In a transmission system, the magnitude of clutch pressure is typically regulated by controlling the magnitude of current to the clutch solenoid. Because production consistency is difficult to guarantee in the production process of the electromagnetic valves, and characteristics of each electromagnetic valve have certain difference, when each electromagnetic valve is produced off line, off-line detection is carried out on each electromagnetic valve, and the corresponding relation between current and actual clutch pressure is tested.

Existing pressure self-learning methods typically correct based on pressure sensor feedback pressure and demand pressure deviations. However, when the feedback pressure is not matched with the actual pressure due to factors such as virtual connection of an electric wire harness, the self-learning result of the clutch pressure is not accurate enough, so that control abnormality is caused, and the driving is seriously influenced.

Disclosure of Invention

The invention provides a clutch pressure self-learning method and device, a vehicle-mounted terminal and a medium, and aims to improve the accuracy of clutch pressure self-learning.

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

acquiring current demand pressure and current actual pressure of a clutch;

according to a prestored valve body project termination EOL data table, dividing the area by pressure, and determining the current pressure division area corresponding to the current required pressure;

acquiring the stay time of the current demand pressure in the current pressure division area;

if the stay time length meets the preset stay time length threshold judgment condition, judging whether clutch pressure self-learning is needed or not according to the current demand pressure and the current actual pressure;

and controlling to carry out clutch pressure self-learning according to the judgment result.

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

the current actual pressure acquisition module is used for acquiring the current required pressure and the current actual pressure of the clutch;

the current division area determining module is used for terminating the pressure division area in the EOL data table according to a prestored valve body project and determining the current pressure division area corresponding to the current required pressure;

the stay time length obtaining module is used for obtaining the stay time length of the current required pressure in the current pressure division area;

the pressure self-learning judging module is used for judging whether clutch pressure self-learning is needed or not according to the current required pressure and the current actual pressure if the stay time meets a preset stay time threshold judging condition;

and the pressure self-learning control module is used for controlling the clutch pressure self-learning according to the judgment result.

According to another aspect of the present invention, there is provided a vehicle-mounted terminal including:

at least one processor; and

a memory communicatively coupled to the at least one processor; wherein the content of the first and second substances,

the memory stores a computer program executable by the at least one processor to enable the at least one processor to perform the clutch pressure self-learning method of any embodiment of the present invention.

According to another aspect of the present invention, a computer-readable storage medium is provided, which stores computer instructions for causing a processor to implement the clutch pressure self-learning method according to any one of the embodiments of the present invention when executed.

The scheme of the embodiment obtains the current demand pressure and the current actual pressure of the clutch; dividing the interval according to the prestored pressure in the valve body EOL data table, and determining the current pressure division interval corresponding to the current required pressure; acquiring the stay time of the current required pressure in the current pressure division area; if the stay time meets the preset stay time threshold judgment condition, judging whether the clutch pressure self-learning is needed or not according to the current demand pressure and the current actual pressure; and controlling to carry out clutch pressure self-learning according to the judgment result. Due to the large rate of change of clutch demand pressure caused by external factors such as electrical, sensor and other mechanical faults, namely, the dwell time between the current pressure division areas is shorter, therefore, the proposal determines whether to carry out clutch pressure learning or not by judging whether the dwell time of the current demand pressure between the current pressure division areas meets the preset dwell time threshold judgment condition or not, thereby effectively avoiding the condition of wrong self-learning of the clutch pressure caused by special conditions such as abnormal clutch pressure establishment caused by virtual connection factors of an electric wire harness or valve body clamping and the like, the clutch pressure learning is not carried out on the current required pressure which does not meet the stay time length threshold judgment condition, so that the accuracy of the clutch pressure self-learning process is improved, the abnormality of clutch pressure control is reduced, and the serious influence on the driving process is avoided.

It should be understood that the statements in this section do not necessarily identify key or critical features of the embodiments of the present invention, nor do they necessarily limit the scope of the invention. Other features of the present invention will become apparent from the following description.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the description below are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a flow chart of a method for self-learning clutch pressure according to an embodiment of the present invention;

FIG. 2 is a flow chart of a clutch pressure self-learning method according to a second embodiment of the invention;

FIG. 3 is a schematic structural diagram of a clutch pressure self-learning device according to a fourth embodiment of the present invention;

FIG. 4 is a schematic structural diagram of an electronic device implementing the clutch pressure self-learning method according to the embodiment of the 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 is to be understood that the terms "current," "target," and the like in the description and claims of the present invention and in the above-described drawings 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 clutch pressure self-learning method according to an embodiment of the present invention, which is applicable to a situation where clutch pressure is self-learned and corrected when a deviation occurs in the clutch pressure, and the method may be performed by a clutch pressure self-learning device, which may be implemented in hardware and/or software, and the clutch pressure self-learning device may be configured in a vehicle-mounted terminal. As shown in fig. 1, the method includes:

and S110, acquiring the current demand pressure and the current actual pressure of the clutch.

Wherein the current demand pressure may be a current required pressure value of the clutch. The current actual pressure may be a current actual pressure value of the clutch. In the absence of a pressure deviation, the current demand pressure of the clutch is the same as the current actual pressure, but the pressure deviation exists as the PI (Proportional Integral) characteristic of the solenoid valve body changes in the life cycle, which causes the demand pressure of the clutch to be inconsistent with the actual pressure. The current demand pressure of the clutch may include a current odd demand pressure and a current even demand pressure, and the current actual pressure may include a current odd actual pressure and a current even actual pressure, among others.

The determination method of the current demand pressure may be to calculate the clutch torque according to the vehicle state, and then obtain the current demand pressure of the clutch through the conversion of the clutch torque value, which may be obtained through the existing demand pressure obtaining method, and this embodiment is not described herein again. The current actual pressure of the clutch can be detected by a clutch pressure sensor.

And S120, according to the prestored valve body project termination pressure division areas in the EOL data table, determining the current pressure division area corresponding to the current required pressure.

The End of item (EOL) data table of the valve body stores pressure division areas of the clutch and mapping relations between the pressure division areas and the current of the electromagnetic valve. And when each solenoid valve is produced off line, performing off-line detection on the solenoid valve, testing the actual corresponding relation between the current of the solenoid valve and the pressure of the clutch, and storing the corresponding relation as off-line detection data of each solenoid valve in an EOL data table of the valve body. Due to differences among different electromagnetic valves, the EOL data tables of the valve bodies corresponding to different electromagnetic valves are different.

It should be noted that the magnitude of the clutch pressure is generally adjusted by controlling the magnitude of the current of the solenoid valve of the clutch, and in the case that there is no pressure deviation, that is, the current required pressure of the clutch is the same as the current actual pressure, the current of the solenoid valve corresponding to the current required pressure may be determined through the data in the EOL data table of the valve body, so as to adjust the clutch pressure by controlling the current of the solenoid valve. However, in practice, the currently demanded pressure of the clutch is not the same as the currently actual pressure due to pressure deviations caused by external and internal influences, and therefore, self-learning of the clutch pressure is required to compensate for the pressure deviations.

For example, the whole range of the clutch pressure interval may be divided into a plurality of pressure intervals to obtain a pressure division interval, and a corresponding relationship between the clutch pressure and the solenoid valve current in the pressure division interval is determined, specifically, the solenoid valve current at the pressure point may be determined according to the pressure point of the clutch pressure, so as to obtain a corresponding relationship between the clutch pressure and the solenoid valve current. The pressure dividing section may include an odd clutch pressure dividing section and an even clutch pressure dividing section. The valve body EOL data table may be as shown in table 1.

TABLE 1

In the valve EOL data table shown in table 1, the solenoid current is increased from 0A to 1.5A in 50mA steps for 31 current points. Each current point has an actual measured pressure for the clutch corresponding to it. When the clutch is used for controlling pressure output, the required control current is obtained according to the clutch pressure by taking the data in the EOL data table as a reference.

For example, the pressure division area to which the current required pressure belongs may be determined according to a pressure division area of a clutch divided in advance in a prestored valve EOL data table, and the pressure division area may be used as the current pressure division area. For example, taking the valve EOL data table as table 1 as an example, if the current odd demand pressure of the clutch is 0.025bar, the odd clutch pressure division corresponding to the current demand pressure is [0.02,0.03 ].

S130, obtaining the stay time of the current required pressure in the current pressure division area.

The stay time of the current demand pressure in the current pressure division area is used for representing the change rate of the current demand pressure, and the longer the stay time is, the smaller the change rate of the demand pressure is; the shorter the dwell time, the greater the rate of change of the demand pressure.

It should be noted that the process of clutch pressure self-learning is a process of learning a pressure deviation, but in actual situations, there is usually a pressure deviation caused by a special situation, not a pressure deviation caused by a normal pressure amplitude change. The pressure deviation caused by special conditions comprises an abnormal clutch pressure establishment caused by an electrical wiring harness virtual connection factor or valve body clamping stagnation and the like. If a special condition occurs, self-learning of the clutch pressure under the special condition can cause an error in the clutch pressure, so that the learning result is inaccurate, and the driving process is seriously influenced.

In general, when the rate of change of the demand pressure between the pressure divisions is large, which is generally caused by a special situation, and when the rate of change of the demand pressure between the pressure divisions is small, which is generally a normal case, it is a pressure deviation that can be corrected by the clutch pressure self-learning. Therefore, whether the clutch pressure self-learning is carried out or not can be judged by judging the change rate of the current required pressure of the clutch in the current pressure dividing area, so that the accuracy of the pressure self-learning is improved, and the condition that the accuracy of the self-learning result is low due to the fact that the pressure self-learning is carried out on the pressure deviation brought by special conditions is avoided. Thus, the rate of change of the current demand pressure may be determined by determining the dwell time period during which the current demand pressure is between the current pressure divisions.

For example, the stay time period during which the current demand pressure is between the current pressure division areas may be obtained by a preset counter. And when the current demand pressure passes through the pressure point corresponding to the current pressure division interval, the timer starts to clear 0 and count time, and the time of the current demand pressure staying in the current pressure interval is recorded. Specifically, if the current pressure division area of the current demand pressure is [0.02,0.03], the timer records the stay time of the current demand pressure in the pressure division area. It should be noted that, if the current demand pressure changes with time and changes to another pressure division interval, for example, to the interval [0.03,0.04], the counter clears 0, terminates the timing of the interval [0.02,0.03], and starts the timing of the stay time of [0.03,0.04 ]. That is, when the counter counts different pressure division areas, the counter performs a zero clearing operation on the previous pressure division area, and then starts to count a new pressure division area.

Optionally, before obtaining the dwell time when the current demand pressure is in the current pressure division area, the method further includes: and judging whether the basic conditions of pressure self-learning are met.

Exemplary, the basic conditions of the pressure self-learning may include: the battery voltage is 11-15V in a specified range; the clutch pressure sensor does not have electrical faults such as open circuit, short circuit, zero drift and the like; the oil temperature of the transmission is between 70 and 90 ℃; the engine has started; reporting related faults of the clutch-free electromagnetic valve; no TCU hardware fault is reported.

And S140, if the stay time meets the preset stay time threshold judgment condition, judging whether the clutch pressure self-learning is needed or not according to the current demand pressure and the current actual pressure.

The determination condition of the dwell time threshold may be preset by a related technician, for example, the dwell time determination condition may be that the dwell time is not less than a preset dwell time threshold, for example, the dwell time threshold may be 10 seconds.

For example, if the stay time is not less than the preset stay time threshold, judging whether the clutch pressure self-learning is needed or not according to the current demand pressure and the current actual pressure; and if the stay time is less than the preset stay time threshold, not performing self-learning of the clutch pressure.

And judging whether the clutch pressure self-learning is needed or not according to the current required pressure and the current actual pressure. Illustratively, if a current pressure difference value between the current demand pressure and the current actual pressure meets a preset pressure difference value judgment condition, clutch pressure self-learning is carried out; and if the current pressure difference between the current required pressure and the current actual pressure does not meet the preset pressure difference judgment condition, not performing clutch pressure self-learning.

Wherein, the pressure difference value judgment condition can be preset by the related technical personnel. For example, the pressure difference determination condition may be that whether an absolute value of a difference between the current pressure difference and a historical pressure difference obtained last time between the current pressure divisions is smaller than a preset difference absolute value threshold is determined, and if so, the pressure difference determination condition is satisfied. It should be noted that the pressure difference calculated each time between each pressure division region may be stored, so as to facilitate the subsequent acquisition of the historical pressure difference.

Illustratively, if the current demand pressure is 0.025bar, the current actual pressure is 0.027bar, and the current pressure division is [ P1, P2], then the current pressure differential is 0.002 bar. And acquiring the historical pressure difference value obtained in the last time between the pressure division areas [ P1, P2], wherein if the historical pressure difference value is 0.003bar, the absolute value of the difference value between the current pressure difference value and the historical pressure difference value is 0.001 bar. If the preset difference absolute value threshold is 0.0015bar, it can be determined that the pressure difference between the current demand pressure and the current actual pressure is smaller than the preset difference absolute value threshold, and therefore, the clutch pressure self-learning can be performed when the current pressure difference meets the preset pressure difference judgment condition.

And S150, controlling to perform clutch pressure self-learning according to the judgment result.

The clutch pressure self-learning can be a process of self-learning and continuously updating the pressure compensation value of the clutch. The pressure self-learning compensation data generated during the clutch pressure self-learning process may be as shown in table 2.

TABLE 2

The pressure self-learning compensation of the clutches can comprise odd clutch pressure self-learning compensation and even clutch pressure self-learning compensation. The clutch pressure points correspond to the clutch pressure points in the EOL data table of the valve body, i.e., the clutch pressure self-learning compensation interval corresponds to the pressure division interval in the EOL data table. The corresponding relation between the pressure self-learning compensation interval and the pressure division interval can be established through the pressure point of the clutch. The clutch pressure self-learning process may be a process of updating clutch pressure self-learning compensation data, and specifically may be a process of updating an interval value of a clutch pressure self-learning compensation interval.

Wherein, P in Table 2 _i1-offset Represents P _i The self-learning compensation value of the pressure of the clutch with odd number; p _i1+1-offset Represents P _i+1 The odd clutch pressure self-learns the compensation value. P _i2-offset Represents P _i The even number of clutch pressure self-learning compensation values; p _i1+1-offset Represents P _i+1 The odd clutch pressure self-learns the compensation value.

In an alternative embodiment, the controlling of the clutch pressure self-learning based on the determination result includes: if clutch pressure self-learning is needed, dividing the interval according to the current pressure deviation, the current demand pressure and the current pressure, and determining a pressure compensation value corresponding to the current demand pressure; and obtaining the target clutch pressure according to the current demand pressure and the pressure compensation value.

For example, the area can be divided according to the current pressure deviation, the current demand pressure and the current pressure, and a rule is determined based on a preset pressure compensation value, so that the corresponding pressure self-learning compensation area between the current pressure division areas is updated; and determining a pressure compensation value corresponding to the current demand pressure according to the updated pressure self-learning compensation interval.

Wherein, the pressure compensation value determination rule can be preset by the related technical personnel, and the pressure compensation value determination rule can be as follows:

P _i-offset ＝(Pupdate-P _i )*P _{i-offset-update} /(P _i+1 -P _i )；

P _i+1-offset ＝(P _i+1 -Pupdate)*P _{i-offset-update} /(P _i+1 -P _i )；

wherein, P _{i-offset-update} Is a pressure learning value. [ P ] _i ,P _i+1 ]Dividing the interval for the current pressure; pupdate is the current demand pressure; [ P ] _i-offset ,P _i+1-offset ]And dividing a corresponding current pressure compensation interval for the current pressure. P _{i-offset-update} ＝Min[P _i-error ,P _i-offet-step ]. Wherein, P _i-error For the current pressure deviation, P _i-offet-step The step length is learned for a preset pressure.

The current pressure division interval [ P ] can be determined through the pressure compensation value determination rule _i ,P _i+1 ]Corresponding current pressure compensation interval [ P ] _i-offset ,P _i+1-offset ]Then the interval [ P ] can be divided according to the current demand pressure based on the current pressure _i ,P _i+1 ]A current pressure compensation interval [ P ] corresponding to the current pressure division interval _i-offset ,P _i+1-offset ]And determining a pressure compensation value. And obtaining the target clutch pressure according to the current demand pressure and the pressure compensation value. The target clutch pressure may be the sum of the current demand pressure and the pressure compensation value, among others.

For example, if the current demand pressure is 0.025bar, the current pressure division interval is [0.02,0.03], and the corresponding current pressure compensation interval is [0.01,0.02], it may be determined that the current demand pressure corresponds to a pressure compensation value of 0.015bar, and the target clutch pressure is 0.04 bar.

In the optional embodiment, the interval is divided according to the current pressure deviation, the current demand pressure and the current pressure, and the pressure compensation value corresponding to the current demand pressure is determined based on the preset pressure compensation value determination rule, so that the accurate determination of the pressure compensation value corresponding to the current demand pressure is realized; thereby improving the accuracy of the target clutch pressure determined from the current demand pressure and the pressure compensation value.

In an optional embodiment, a target solenoid valve current corresponding to the target clutch pressure is determined based on the mapping relationship between different clutch pressures and solenoid valve currents in the valve body item termination EOL data table; and controlling the pedal opening of the clutch according to the target electromagnetic valve current.

The target solenoid current may be a current for adjusting the clutch pressure and controlling the pedal opening of the clutch. The valve body EOL data table includes mapping relationships between different clutch pressures and solenoid valve currents. The target clutch pressure may include a target odd clutch pressure and a target even clutch pressure.

For example, if the target odd clutch pressure is 0.025bar, the valve body EOL data table is shown in table 1. The target solenoid current may be determined to be 0.075A from the mapping between clutch pressure and solenoid current shown in table 1.

In the optional embodiment, the target solenoid valve current corresponding to the target clutch pressure is determined based on the mapping relation between different clutch pressures and solenoid valve currents in the valve body project termination EOL data table, so that the clutch pressure is adjusted through the target solenoid valve current, and the pedal opening of the clutch is controlled.

The scheme of the embodiment obtains the current demand pressure and the current actual pressure of the clutch; dividing the interval according to the prestored pressure in the valve body EOL data table, and determining the current pressure division interval corresponding to the current required pressure; acquiring the stay time of the current required pressure in the current pressure division area; if the stay time meets the preset stay time threshold judgment condition, judging whether the clutch pressure self-learning is needed or not according to the current demand pressure and the current actual pressure; and controlling to carry out clutch pressure self-learning according to the judgment result. Due to the large rate of change of clutch demand pressure caused by external factors such as electrical, sensor and other mechanical faults, namely, the dwell time between the current pressure division areas is short, therefore, the scheme determines whether to carry out clutch pressure learning or not by judging whether the dwell time of the current required pressure between the current pressure division areas meets the preset dwell time threshold judgment condition or not, effectively avoids the condition of wrong self-learning of the clutch pressure caused by special conditions such as abnormal clutch pressure establishment caused by virtual connection factors of an electric wire harness or valve body clamping stagnation and the like, the clutch pressure learning is not carried out on the current required pressure which does not meet the stay time length threshold judgment condition, so that the accuracy of the clutch pressure self-learning process is improved, the abnormality of clutch pressure control is reduced, and the serious influence on the driving process is avoided.

Example two

Fig. 2 is a flowchart of a clutch pressure self-learning method according to a second embodiment of the present invention, and the second embodiment of the present invention is optimized and improved based on the above technical solutions.

Further, the step of judging whether to carry out clutch pressure self-learning or not according to the current demand pressure and the current actual pressure is refined into the step of determining the pressure change amplitude according to the current demand pressure and the current actual pressure; and judging whether to carry out clutch pressure self-learning or not according to the pressure change amplitude. "to complete the judgment process of self-learning whether to carry out clutch pressure.

As shown in fig. 2, the method comprises the following specific steps:

and S210, acquiring the current required pressure and the current actual pressure of the clutch.

And S220, terminating the pressure division area in the EOL data table according to the prestored valve body item, and determining the current pressure division area corresponding to the current required pressure.

And S230, acquiring the stay time of the current required pressure in the current pressure division area.

S240, if the stay time meets the preset stay time threshold judgment condition, determining the pressure change amplitude according to the current required pressure and the current actual pressure.

Wherein the pressure change amplitude is used to indicate the stability of the pressure change. The pressure variation range may be a variation range between a pressure deviation between the current required pressure and the current actual pressure determined this time within the current pressure division range and a pressure deviation between the historical pressure determined last time within the current pressure division range.

In an alternative embodiment, determining the magnitude of the pressure change based on the current demand pressure and the current actual pressure comprises: determining a current pressure deviation according to the current demand pressure and the current actual pressure; storing the current pressure deviation, and acquiring the historical pressure deviation between the last stored current pressure division areas; and determining the pressure change amplitude according to the current pressure deviation and the historical pressure deviation.

Wherein the current pressure deviation may be a difference between the current demand pressure and the current actual pressure. The historical pressure deviations may be pressure deviations taken within a current pressure division during a historical time.

For example, the difference between the current demand pressure and the current actual pressure may be used as the current pressure deviation, and the current pressure deviation may be stored for subsequent acquisition of the pressure deviation determined this time. And acquiring historical pressure deviation between the current pressure division areas stored last time, and taking the absolute value of the deviation between the current pressure deviation and the historical pressure deviation as the pressure change amplitude.

In the optional embodiment, the current pressure deviation is determined according to the current demand pressure and the current actual pressure; the pressure change amplitude is determined according to the current pressure deviation and the historical pressure deviation, so that the pressure change amplitude is accurately determined, and the accuracy of judging whether to perform clutch pressure self-learning or not according to the subsequent judgment of the pressure change amplitude is improved.

And S250, judging whether to carry out self-learning of the clutch pressure according to the pressure change amplitude.

It should be noted that, if the current required pressure and the current actual pressure deviate due to electrical factors, mechanical factors, etc., the variation range of the pressure deviation is unstable, and the pressure deviation is difficult to keep consistent every two times when the same pressure division interval is passed, that is, the pressure variation range is large. If the PI characteristic of the valve body per se changes in the life cycle, the pressure deviation is relatively stable and can be basically kept consistent when the pressure dividing area passes through twice, namely the pressure change amplitude is small.

Illustratively, whether to carry out clutch pressure self-learning is judged according to the pressure change amplitude. If the pressure variation amplitude is large, the pressure deviation possibly caused by external factors is possible, and the clutch pressure self-learning is not carried out; if the pressure change amplitude is small, the PI characteristic of the valve body can be considered to be changed, and the clutch pressure self-learning is carried out.

In an alternative embodiment, the determining whether to perform clutch pressure self-learning based on the magnitude of the pressure change comprises: judging whether the pressure variation amplitude is not larger than a preset variation amplitude threshold value or not; if so, determining the accumulated times that the pressure change amplitude is not greater than a preset change amplitude threshold; and judging whether to carry out clutch pressure self-learning or not based on a preset pressure self-learning judgment condition according to the accumulated times.

Wherein the threshold value of the variation amplitude may be preset by a person skilled in the relevant art, for example, the threshold value of the variation amplitude may be 0.1 bar.

For example, the cumulative number of times that the pressure change amplitude is not greater than the preset change amplitude threshold may be determined by a preset counter. Specifically, when the pressure variation amplitude is not greater than a preset variation amplitude threshold value, the pressure variation amplitude is considered to be small, the pressure deviation is relatively stable, and a counter is adopted to add 1 to a count value corresponding to the current pressure division area to obtain the accumulated times; when the pressure variation amplitude is larger than the preset variation amplitude threshold value, the pressure variation amplitude is considered to be large, the pressure deviation is unstable, and the counter is adopted to subtract 1 from the corresponding count value of the current pressure division area to obtain the accumulated times.

And judging whether to carry out clutch pressure self-learning or not based on a preset pressure self-learning judgment condition according to the accumulated times. The pressure self-learning judgment condition can be preset by related technicians according to actual requirements. For example, the pressure self-learning judgment condition may be that whether the accumulated number of times is greater than a preset number accumulated threshold value is judged, and if so, clutch pressure self-learning is performed; if not, clutch pressure self-learning is not carried out. Wherein, the number accumulation threshold may be 3 times.

According to the optional embodiment, whether the clutch pressure self-learning mode is carried out or not is judged by determining the accumulated times that the pressure change amplitude is not greater than the preset change amplitude threshold value and based on the preset pressure self-learning judgment condition according to the accumulated times, so that the situation that the change amplitude of the pressure deviation is unstable when the current required pressure and the current actual pressure are deviated due to factors such as electrical factors and machinery is avoided, and the accuracy of clutch pressure self-learning judgment is improved.

And S260, controlling to carry out self-learning of the clutch pressure according to the judgment result.

According to the scheme of the embodiment, the pressure change amplitude is determined according to the current required pressure and the current actual pressure; and judging whether to perform clutch pressure self-learning or not according to the pressure change amplitude, so that the judgment accuracy of the clutch pressure self-learning is realized. When the current required pressure and the current actual pressure are deviated due to external factors such as electricity and machinery, the amplitude of the pressure deviation is unstable, the condition that clutch pressure self-learning is carried out on the unstable pressure deviation is avoided, and the accuracy of the clutch pressure self-learning is improved.

EXAMPLE III

The embodiment of the application provides a preferred implementation mode on the basis of the technical solutions of the above embodiments.

The magnitude of the clutch pressure is typically regulated by controlling the magnitude of the current to the clutch solenoid. In the production process of the electromagnetic valves, the production consistency is difficult to ensure, and the characteristics of each electromagnetic valve have difference, so that off-line detection is carried out on each electromagnetic valve when the electromagnetic valve is produced off-line, the corresponding relation between the current and the actual clutch pressure is tested, and the corresponding relation is used as off-line detection data of each clutch electromagnetic valve block, namely valve EOL data. However, in the whole life cycle of the valve body carrying the transmission matched with the whole vehicle, the corresponding relation between the clutch pressure and the electromagnetic valve current may change to a certain extent, and the clutch pressure needs to be learned by self to correct the pressure deviation.

The valve EOL data table shown in table 1 is used to characterize the clutch solenoid current versus clutch pressure correspondence, with the current increasing from 0A to 1.5A in 50mA steps for 31 current points. The measured pressure of the clutch corresponds to each current point, and when the clutch outputs control pressure, the required control current is back-calculated according to the required pressure by taking the data in the EOL data table of the valve body as the reference.

The clutch pressure self-learning process and implementation steps of the present embodiment are further described below:

the first step is as follows: according to the valve body EOL data table, a pressure division interval is determined, the whole clutch pressure interval range is divided into a plurality of pressure interval sections, the pressure interval section where the required pressure is located is calculated in real time and is represented by a pointer Indexi.

The PI characteristics of the valve body during the just offline process can be obtained according to a valve body EOL data table obtained in a data form of the valve body during the offline detection of the EOL, for example, 31 current points in the valve body EOL data table shown in table 1 correspond to 31 pressure points, and 30 pressure intervals. Meanwhile, the 30 pressure sections are also used as pressure dividing sections for pressure self-learning, and correspond to 31 pressure self-learning compensation points. If Indexi is an integer from 1 to 30, it indicates that the current demand pressure is between the ith pressure division (Pi, Pi + 1). During pressure self-learning, the self-learning is recalculated each time Indexi changes, and the calculation result is updated to the pressure learning compensation Pi-offset and Pi +1-offset corresponding to Indexi. Pi-offset and Pi +1-offset correspond to the pressure dividing regions Pi, Pi +1, Pi-offset corresponds to Pi, and Pi +1-offset corresponds to Pi +1, respectively.

The second step is that: judging whether the basic conditions of the pressure self-learning are met or not comprises the following steps: a. the battery voltage is in a specified range (11-15V); b. the clutch pressure sensor does not have electrical faults such as open circuit, short circuit, zero drift and the like; c. the oil temperature of the transmission is between 70 and 90 ℃; d. the engine has started; e. reporting related faults of the clutch-free electromagnetic valve; f. no TCU hardware fault is reported.

The third step: and judging whether the pressure self-learning condition is met or not according to the change rate of the required pressure. The method is realized by the following steps:

when the demand pressure passes through a pressure point Pi in the valve EOL data table, that is, when Indexi changes, the Timer starts to count 0, and the Timer is used for recording the time that the demand pressure stays in the pressure interval indicated by Indexi. When the Timer timing exceeds the set time Tupdate, the residence time of the required pressure in the (Pi, Pi +1) pressure interval is longer, the change rate of the required pressure is smaller, the pressure change is more smooth, the learning condition is met, and the next calculation is continued when the Timer timing reaches the Tupdate time.

The fourth step: when the required pressure and the actual pressure fed back by the sensor have deviation, the stability and repeatability of the pressure deviation need to be judged to determine whether to carry out pressure self-learning.

The method is realized by the following steps: when the Timer counts up to Tupdate, the following processing is required:

a. the deviation Pi-error of the demanded pressure from the actual pressure at this time is recorded and stored in the EEPROM.

b. Reading the Pi-error value stored in the EEPROM at the last time, subtracting the calculated Pi-error value and taking an absolute value to obtain the | Delta Pi-error |. The | Δ Pi-error | represents the pressure deviation of the last required pressure in the pressure interval and the change amplitude of the pressure deviation of the last required pressure in the pressure interval, and can indirectly represent the stability of the pressure. If the deviation between the required pressure and the actual pressure occurs due to electrical factors, mechanical factors and other factors, the amplitude of the pressure deviation is unstable, and the deviation value of the pressure is difficult to keep consistent every two times of passing through the same pressure interval, namely the value of the delta Pi-error is larger. If the PI characteristic of the valve body changes in the life cycle, the pressure deviation is relatively stable every two times of passing through the pressure interval, namely the value of the absolute delta Pi-error is relatively small. The magnitude of the pressure deviation can be used as the basis for judging whether the pressure deviation is stable or not according to the magnitude of the delta Pi-error.

c. When the absolute value of delta Pi-error is less than or equal to Perror-threshold, the difference value of the pressure difference values of the two times is small when the required pressure passes through the pressure interval last time and the pressure interval last time, the pressure deviation is relatively stable, the pressure deviation can be corrected, and the counter Couteri is added with 1. When the absolute value delta Pi-error is larger than the Perror-threshold, the difference value of the pressure difference values of the two times is considered to be large when the required pressure passes through the pressure interval last time and this time, the pressure deviation is unstable, the pressure deviation cannot be corrected, and the counter Couteri is reduced by 1. Wherein, Perror-threshold is used as the threshold for judging whether the two pressure deviations are stable, and can be 0.1 bar. Couteri is used as a deviation stable time counter, the maximum value can be 3, and when the maximum value is exceeded, zero clearing is carried out to count the next cycle.

The fifth step: when the counter value reaches the maximum set value 3, the updating of the pressure learning offset value is performed. The pressure learning value Pi-offset-update is proportionally updated to the pressure compensation points Pi-offset and Pi +1-offset corresponding to the Pi and Pi +1 pressures respectively, and the maximum updating step length Pi-offset-step is limited every time the learning value is subjected to, the Pi-offset-step can be preset, and can be 0.1bar for example. Pi-offset-update takes the minimum of the pressure deviation Pi-error before update and the update step Pi-offset-step, i.e., Pi-offset-update is Min [ Pi-error, Pi-offset-step ]. Pi +1-offset (Pi + 1-pdate) Pi-offset-update/(Pi +1-Pi), where pupate is the required pressure value at the time of learning value update. Pi-offset (Pupdate-Pi) Pi-offset-update/(Pi + 1-Pi).

Example four

Fig. 3 is a schematic structural diagram of a clutch pressure self-learning device according to a fourth embodiment of the present invention. The clutch pressure self-learning device provided by the embodiment of the invention can be suitable for the condition of self-learning correction of the clutch pressure when the clutch pressure has deviation, and can be realized in a software and/or hardware mode. As shown in fig. 3, the apparatus specifically includes: a current actual pressure obtaining module 301, a current divided zone determining module 302, a stay time obtaining module 303, a pressure self-learning judging module 304 and a pressure self-learning control module 305. Wherein the content of the first and second substances,

a current actual pressure obtaining module 301, configured to obtain a current required pressure and a current actual pressure of the clutch;

a current division interval determining module 302, configured to terminate a pressure division interval in an EOL data table according to a pre-stored valve body item, and determine a current pressure division interval corresponding to the current demand pressure;

a stay time length obtaining module 303, configured to obtain a stay time length when the current required pressure is in the current pressure division area;

the pressure self-learning judging module 304 is configured to judge whether clutch pressure self-learning is required according to the current demand pressure and the current actual pressure if the dwell time meets a preset dwell time threshold judging condition;

and the pressure self-learning control module 305 is used for controlling the clutch pressure self-learning according to the judgment result.

Optionally, the pressure self-learning determining module 304 includes:

the pressure change amplitude determining unit is used for determining the pressure change amplitude according to the current demand pressure and the current actual pressure;

and the pressure self-learning judging unit is used for judging whether to carry out clutch pressure self-learning or not according to the pressure change amplitude.

Optionally, the pressure variation amplitude determining unit includes:

a current pressure deviation determining subunit, configured to determine a current pressure deviation according to the current demand pressure and the current actual pressure;

a historical pressure deviation obtaining subunit, configured to store the current pressure deviation, and obtain a historical pressure deviation between last stored current pressure divisions;

and the pressure change amplitude determining subunit is used for determining the pressure change amplitude according to the current pressure deviation and the historical pressure deviation.

Optionally, the pressure self-learning determining unit includes:

the threshold judging subunit is used for judging whether the pressure change amplitude is not greater than a preset change amplitude threshold;

the accumulated frequency determining subunit is used for determining the accumulated frequency that the pressure change amplitude is not greater than the preset change amplitude threshold value if the pressure change amplitude is not greater than the preset change amplitude threshold value;

and the pressure self-learning judgment subunit is used for judging whether to carry out clutch pressure self-learning or not according to the accumulated times and based on preset pressure self-learning judgment conditions.

Optionally, the pressure self-learning control module 305 includes:

the pressure compensation determining unit is used for dividing the interval according to the current pressure deviation, the current demand pressure and the current pressure and determining a pressure compensation value corresponding to the current demand pressure if clutch pressure self-learning is required;

and the target clutch pressure determining unit is used for obtaining the target clutch pressure according to the current demand pressure and the pressure compensation value.

Optionally, the apparatus further comprises:

the target solenoid valve current determining module is used for determining target solenoid valve current corresponding to the target clutch pressure based on the mapping relation between different clutch pressures and solenoid valve currents in the valve body project termination EOL data table;

and the pedal opening control module is used for controlling the pedal opening of the clutch according to the target electromagnetic valve current.

The clutch pressure self-learning device can execute the clutch pressure self-learning method provided by any embodiment of the invention, and has corresponding functional modules and beneficial effects for executing the clutch pressure self-learning methods.

EXAMPLE five

Fig. 4 shows a schematic configuration diagram of the in-vehicle terminal 40 that can be used to implement an embodiment of the present invention. Vehicle terminals are intended to represent various forms of digital computers, such as laptops, desktops, workstations, personal digital assistants, servers, blade servers, mainframes, and other appropriate computers. The in-vehicle terminal may also represent various forms of mobile devices, such as personal digital assistants, cellular phones, smart phones, wearable devices (e.g., helmets, glasses, watches, etc.), and other similar computing devices. The components shown herein, their connections and relationships, and their functions, are meant to be exemplary only, and are not meant to limit implementations of the inventions described and/or claimed herein.

As shown in fig. 4, the in-vehicle terminal 40 includes at least one processor 41, and a memory communicatively connected to the at least one processor 41, such as a Read Only Memory (ROM)42, a Random Access Memory (RAM)43, and the like, where the memory stores a computer program executable by the at least one processor, and the processor 41 may perform various appropriate actions and processes according to the computer program stored in the Read Only Memory (ROM)42 or the computer program loaded from the storage unit 48 into the Random Access Memory (RAM) 43. In the RAM 43, various programs and data necessary for the operation of the in-vehicle terminal 40 can also be stored. The processor 41, the ROM 42, and the RAM 43 are connected to each other via a bus 44. An input/output (I/O) interface 45 is also connected to bus 44.

A plurality of components in the in-vehicle terminal 40 are connected to the I/O interface 45, including: an input unit 46 such as a keyboard, a mouse, etc.; an output unit 47 such as various types of displays, speakers, and the like; a storage unit 48 such as a magnetic disk, an optical disk, or the like; and a communication unit 49 such as a network card, modem, wireless communication transceiver, etc. The communication unit 49 allows the in-vehicle terminal 40 to exchange information/data with other devices through a computer network such as the internet and/or various telecommunication networks.

Processor 41 may be a variety of general and/or special purpose processing components having processing and computing capabilities. Some examples of processor 41 include, but are not limited to, a Central Processing Unit (CPU), a Graphics Processing Unit (GPU), various specialized Artificial Intelligence (AI) computing chips, various processors running machine learning model algorithms, a Digital Signal Processor (DSP), and any suitable processor, controller, microcontroller, or the like. Processor 41 performs the various methods and processes described above, such as the clutch pressure self-learning method.

In some embodiments, the clutch pressure self-learning method may be implemented as a computer program tangibly embodied in a computer-readable storage medium, such as storage unit 48. In some embodiments, part or all of the computer program may be loaded and/or installed on the in-vehicle terminal 40 via the ROM 42 and/or the communication unit 49. When the computer program is loaded into the RAM 43 and executed by the processor 41, one or more steps of the clutch pressure self-learning method described above may be performed. Alternatively, in other embodiments, processor 41 may be configured to perform the clutch pressure self-learning method by any other suitable means (e.g., by way of firmware).

Various implementations of the systems and techniques described here above may be implemented in digital electronic circuitry, integrated circuitry, Field Programmable Gate Arrays (FPGAs), Application Specific Integrated Circuits (ASICs), Application Specific Standard Products (ASSPs), system on a chip (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, and/or combinations thereof. These various embodiments may include: implemented in one or more computer programs that are executable and/or interpretable on a programmable system including at least one programmable processor, which may be special or general purpose, receiving data and instructions from, and transmitting data and instructions to, a storage system, at least one input device, and at least one output device.

A computer program for implementing the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the computer programs, when executed by the processor, cause the functions/acts specified in the flowchart and/or block diagram block or blocks to be performed. A computer program can execute entirely on a machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

In the context of the present invention, a computer-readable storage medium may be a tangible medium that can contain, or store a computer program for use by or in connection with an instruction execution system, apparatus, or device. A computer readable storage medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. Alternatively, the computer readable storage medium may be a machine readable signal medium. More specific examples of a machine-readable storage medium would include an electrical connection based on one or more wires, a portable computer diskette, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

To provide for interaction with a user, the systems and techniques described here may be implemented on a vehicle terminal having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to a user; and a keyboard and a pointing device (e.g., a mouse or a trackball) by which a user can provide input to the in-vehicle terminal. Other kinds of devices may also be used to provide for interaction with a user; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user may be received in any form, including acoustic, speech, or tactile input.

The systems and techniques described here can be implemented in a computing system that includes a back-end component (e.g., as a data server), or that includes a middleware component (e.g., an application server), or that includes a front-end component (e.g., a user computer having a graphical user interface or a web browser through which a user can interact with an implementation of the systems and techniques described here), or any combination of such back-end, middleware, or front-end components. The components of the system can be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: local Area Networks (LANs), Wide Area Networks (WANs), blockchain networks, and the internet.

The computing system may include clients and servers. A client and server are generally remote from each other and typically interact through a communication network. The relationship of client and server arises by virtue of computer programs running on the respective computers and having a client-server relationship to each other. The server can be a cloud server, also called a cloud computing server or a cloud host, and is a host product in a cloud computing service system, so that the defects of high management difficulty and weak service expansibility in the traditional physical host and VPS service are overcome.

It should be understood that various forms of the flows shown above may be used, with steps reordered, added, or deleted. For example, the steps described in the present invention may be executed in parallel, sequentially, or in different orders, and are not limited herein as long as the desired results of the technical solution of the present invention can be achieved.

The above-described embodiments should not be construed as limiting the scope of the invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions may be made in accordance with design requirements and other factors. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method of self-learning clutch pressure, comprising:

acquiring current demand pressure and current actual pressure of a clutch;

according to a prestored pressure division area in the valve body project termination EOL data table, determining a current pressure division area corresponding to the current demand pressure;

2. The method of claim 1, wherein said determining whether to perform clutch pressure self-learning based on said current demand pressure and said current actual pressure comprises:

determining the pressure change amplitude according to the current demand pressure and the current actual pressure;

and judging whether to carry out clutch pressure self-learning or not according to the pressure change amplitude.

3. The method of claim 2, wherein said determining a pressure change magnitude from said current demand pressure and said current actual pressure comprises:

determining a current pressure deviation according to the current demand pressure and the current actual pressure;

storing the current pressure deviation, and acquiring the historical pressure deviation between the last stored current pressure division areas;

and determining the pressure change amplitude according to the current pressure deviation and the historical pressure deviation.

4. The method of claim 2, wherein said determining whether to perform clutch pressure self-learning based on said magnitude of pressure change comprises:

judging whether the pressure variation amplitude is not larger than a preset variation amplitude threshold value or not;

if so, determining the accumulated times that the pressure change amplitude is not greater than a preset change amplitude threshold;

and judging whether to carry out clutch pressure self-learning or not based on a preset pressure self-learning judgment condition according to the accumulated times.

5. The method according to any one of claims 1-4, wherein said controlling clutch pressure self-learning based on the determination result comprises:

if clutch pressure self-learning is needed, dividing the interval according to the current pressure deviation, the current demand pressure and the current pressure, and determining a pressure compensation value corresponding to the current demand pressure;

and obtaining the target clutch pressure according to the current demand pressure and the pressure compensation value.

6. The method of claim 5, further comprising:

determining a target solenoid valve current corresponding to the target clutch pressure based on a mapping relation between different clutch pressures and solenoid valve currents in the valve body item termination EOL data table;

and controlling the pedal opening of the clutch according to the target electromagnetic valve current.

7. A clutch pressure self-learning device, comprising:

8. A vehicle-mounted terminal, characterized in that the vehicle-mounted terminal comprises:

at least one processor; and

a memory communicatively coupled to the at least one processor; wherein, the first and the second end of the pipe are connected with each other,

the memory stores a computer program executable by the at least one processor to enable the at least one processor to perform the clutch pressure self-learning method of any one of claims 1-6.

9. A vehicle characterized in that the vehicle is provided with the in-vehicle terminal according to claim 8.

10. A computer readable storage medium storing computer instructions for causing a processor to perform the clutch pressure self-learning method of any one of claims 1-6 when executed.