CN113944560A

CN113944560A - Self-adaptive control method and device for clutch

Info

Publication number: CN113944560A
Application number: CN202010692863.5A
Authority: CN
Inventors: 张鹏君; 侯清亮; 宗大伟; 薛康
Original assignee: SAIC Motor Corp Ltd
Current assignee: SAIC Motor Corp Ltd
Priority date: 2020-07-17
Filing date: 2020-07-17
Publication date: 2022-01-18
Anticipated expiration: 2040-07-17
Also published as: CN113944560B

Abstract

The application provides a clutch self-adaptive control method and device, which can obtain the current rotating speed of an engine, the instruction torque of the engine and the first instruction torque of a clutch, and determine the response torque which can cause the rotating speed of the engine to be obviously reduced at the current rotating speed according to the current rotating speed; when the command torque of the engine is larger than the response torque, correcting the first command torque according to the command torque and the response torque of the engine to obtain a second command torque so as to control the clutch to be closed according to the second command torque; it follows that when the engine is about to be towed to a lower speed, the speed at which the clutch closes is slowed, thereby increasing the time required for clutch closure; in this process, the actual output torque of engine can adapt to the instruction moment of torsion of clutch gradually, can not be dragged to lower rotational speed, so, can promote driver's driving experience, improve the life of engine simultaneously.

Description

Self-adaptive control method and device for clutch

Technical Field

The application relates to the technical field of automobiles, in particular to a clutch self-adaptive control method and device.

Background

Clutches are important components of automotive power systems, are installed between an engine and a transmission, and are used for cutting off or transmitting power between the engine and an automotive power train. In a starting acceleration condition of the automobile from starting to normal running, a driver can operate the clutch according to requirements to enable the engine and the transmission system to be temporarily separated or gradually connected, so that the power output from the engine to the transmission system is cut off or transmitted.

When the vehicle starts to accelerate, the engine has high rotating speed, and the clutch can not be closed immediately due to the speed difference of the clutch main driving disc and the clutch auxiliary driving disc, so that the whole vehicle can be dragged to the current engine rotating speed from the low rotating speed by slowly closing the clutch. At the moment, the vehicle starting working condition depends on the engine end to drag the vehicle to a higher speed through the clutch sliding mill to complete the clutch locking, and then the power is normally output.

However, if the engine is slow to increase its output, it is not possible to simultaneously provide sufficient torque to the clutch and maintain its high speed operation. Therefore, the engine speed can be dragged to a lower speed by the clutch in the process of closing the clutch, so that a driver feels obvious setback and the driving experience of the driver is reduced.

Disclosure of Invention

In view of this, embodiments of the present application provide a clutch adaptive control method and apparatus, which aim to slow down a closing speed of a clutch according to an actual working condition of a transmitter, so as to prevent an engine from being dragged to a lower rotation speed.

A method of adaptive clutch control, the method comprising:

acquiring the current rotating speed of an engine, the command torque of the engine and the first command torque of a clutch;

determining a response torque corresponding to the current rotating speed according to the corresponding relation between the rotating speed of the engine and the response torque;

when the command torque of the engine is larger than or equal to the response torque, correcting the first command torque according to the command torque of the engine and the response torque to obtain a second command torque of the clutch, wherein the second command torque is smaller than the first command torque;

and controlling the clutch to close according to the second command torque.

Optionally, the determining the response torque corresponding to the current rotation speed according to the corresponding relationship between the engine rotation speed and the response torque includes:

acquiring current atmospheric pressure;

and determining response torque corresponding to the current rotating speed and the current atmospheric pressure according to the corresponding relation among the atmospheric pressure, the engine rotating speed and the response torque.

Optionally, the modifying the first command torque according to the command torque of the engine and the response torque to obtain the second command torque of the clutch comprises:

and correcting the first instruction torque according to the instruction torque of the engine, the response torque and the second instruction torque of the previous period to obtain the second instruction torque.

Optionally, the modifying the first command torque according to the command torque of the engine, the response torque and the second command torque of the previous period to obtain the second command torque comprises:

calculating a torque deviation factor from a command torque of the engine and the response torque, the torque deviation factor representing a degree to which the command torque of the engine is greater than the response torque;

calculating a first torque variation according to a difference value between the second instruction torque of the previous period and the response torque;

calculating to obtain a second torque variation according to the torque deviation coefficient and the first torque variation;

and calculating to obtain the second instruction torque of the period according to the second torque variation and the second instruction torque of the previous period.

Optionally, when the power output shaft connected to the clutch is also connected to an electric motor, the method further comprises:

obtaining a compensation torque according to the difference value of the first instruction torque and the second instruction torque;

and controlling the motor to output according to the compensation torque.

A clutch adaptation control apparatus, the apparatus comprising:

the acquisition module is used for acquiring the current rotating speed of the engine, the command torque of the engine and the first command torque of the clutch;

the response determining module is used for determining the response torque corresponding to the current rotating speed according to the corresponding relation between the rotating speed of the engine and the response torque;

the correction calculation module is used for correcting the first instruction torque according to the instruction torque and the response torque of the engine to obtain a second instruction torque of the clutch when the instruction torque of the engine is larger than or equal to the response torque, and the second instruction torque is smaller than the first instruction torque;

and the closing control module is used for controlling the clutch to be closed according to the second command torque.

Optionally, the response determination module is configured to obtain a current atmospheric pressure; and determining response torque corresponding to the current rotating speed and the current atmospheric pressure according to the corresponding relation among the atmospheric pressure, the engine rotating speed and the response torque.

Optionally, the correction calculation module is configured to correct the first command torque according to a command torque of the engine, the response torque, and a second command torque of a previous cycle, so as to obtain a second command torque.

Optionally, the correction calculation module includes:

a deviation calculation module for calculating a torque deviation factor from a commanded torque and the response torque of the engine, the torque deviation factor representing a degree to which the commanded torque is greater than the response torque of the engine;

the first variable quantity calculating module is used for calculating a first torque variable quantity according to a difference value of the second instruction torque of the previous period and the response torque;

the second variable quantity calculation module is used for calculating a second torque variable quantity according to the torque deviation coefficient and the first torque variable quantity;

and the instruction calculation module is used for calculating the second instruction torque of the period according to the second torque variation and the second instruction torque of the previous period.

Optionally, when the power output shaft connected to the clutch is further connected to an electric motor, the apparatus further comprises:

the compensation calculation module is used for obtaining a compensation torque according to the difference value of the first instruction torque and the second instruction torque;

and the motor control module is used for controlling the motor to output according to the compensation torque.

The application provides a clutch self-adaptive control method and device, which can obtain the current rotating speed of an engine, the instruction torque of the engine and the first instruction torque of a clutch, and determine the response torque which can cause the rotating speed of the engine to be obviously reduced at the current rotating speed according to the current rotating speed; when the command torque of the engine is larger than the response torque, correcting the first command torque according to the command torque of the engine and the response torque to obtain a second command torque, and finally controlling the clutch to be closed according to the second command torque; it can be seen that when the engine is about to be towed to a lower speed, the speed at which the clutch is closed is slowed, thereby increasing the time required for the clutch to close, and providing sufficient time for the output power of the engine to increase to the required power. At this in-process, the actual output torque of engine can adapt to the instruction moment of torsion of clutch gradually, can not be dragged to lower rotational speed, so, the engine can be kept improving output torque gradually when higher rotational speed to satisfy the demand of the instruction moment of torsion of clutch, thereby avoid the driver to feel and frustrate, promote and drive and experience, can also improve the life of engine simultaneously.

Drawings

To illustrate the technical solutions in the present embodiment or the prior art more clearly, the drawings needed to be used in the description of the embodiment or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, 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 of an adaptive clutch control method according to an embodiment of the present disclosure.

Fig. 2 is a waveform diagram of the command torque before and after the correction provided by the embodiment of the present application.

Fig. 3 is a schematic structural diagram of a hybrid system according to an embodiment of the present application.

Fig. 4 is a schematic structural diagram of an adaptive clutch control apparatus according to an embodiment of the present disclosure.

Fig. 5 is a schematic structural diagram of an adaptive clutch control apparatus according to an embodiment of the present disclosure.

Fig. 6 is a schematic structural diagram of a clutch adaptive control apparatus according to an embodiment of the present disclosure.

Detailed Description

The clutch is a common component in mechanical transmission, and comprises a driving disk and a driven disk, and is arranged between an engine and a transmission, so that a transmission system can be separated or connected at any time, and the power provided by the engine is cut off or transmitted to a power output shaft. In the starting acceleration working condition of the engine, the control system can control the clutch to be closed, so that the engine can transmit power to the power output shaft through the clutch, the gearbox and other parts, and thus work is done outwards. When gear shifting is required, the control system can firstly control the clutch to be separated to stop power transmission, then after the meshing relation of gears in the gearbox is changed, finally the clutch is closed to recover power transmission.

When the clutch is separated from the driving disc and the driven disc, the engine is in an idle state, and the output torque is very small. During the process of closing the clutch, the engine is switched from an idle state to a load state, and the output torque is greatly increased. In this way, the control system can control the working state of the engine by controlling the separation and the closing of the clutch, so as to start the equipment or change gears.

However, existing clutch control systems are relatively fast in closing speed. If the engine performance is poor, the output power change speed is slow. Since the output power of the engine is the product of the output torque and the rotating speed, the slow change speed of the output power of the engine can cause that the engine cannot adapt to the large change of the output torque in a short time. That is, existing clutch control systems are unable to maintain the engine speed when the clutch is closed, resulting in the engine being towed to a lower speed. This not only reduces the driving experience for the driver, but also reduces the useful life of the engine internals.

In order to provide a scheme that the engine speed can be maintained by changing a Control system without changing the structure of a power system, the application provides a clutch adaptive Control method and a clutch adaptive Control device, and a preferred embodiment of the application is described in the following from the perspective of a clutch closing Control system or an Electronic Control Unit (ECU). It should be noted that the present application can be used in a conventional power vehicle or a hybrid vehicle, and can also be used in any other mechanical device in which a power system includes a clutch.

Referring to fig. 1, fig. 1 is a flowchart of an adaptive clutch control method according to an embodiment of the present application, including:

s101: a current rotational speed of the engine, a commanded torque of the engine, and a first commanded torque of the clutch are obtained.

In this embodiment, the clutch closure control system may first acquire relevant parameters including a current rotation speed of the engine, a torque command of the engine, and a first command of the clutch when controlling the closure of the clutch. These parameters can be used to design control commands that are consistent with the current state of the engine and clutch to control clutch closure.

The command torque of the engine and the first command torque of the clutch are control quantities used by other control systems (such as an engine control system, a gear shift control system and the like) for controlling the engine or the clutch, and can be directly obtained from the other control systems. The current rotational speed of the engine can be measured by an existing rotational speed sensor. In this way, the clutch closure control system can obtain relevant parameters for controlling the closure of the clutch without additionally adding measuring equipment.

S102: and determining the response torque corresponding to the current rotating speed according to the corresponding relation between the rotating speed of the engine and the response torque.

After obtaining the relevant parameters, the clutch closing control system may determine a response torque corresponding to the current rotational speed of the engine in combination with a correspondence between the rotational speed of the engine and the response torque. The corresponding relation between the engine speed and the response torque can be measured in advance through experiments, the response torque represents the command torque of the engine which can cause the engine speed to be obviously reduced in the clutch closing process, a speed-time curve of the engine in the clutch closing process can be obtained through tests, and the command torque at the inflection point of the curve is selected as the corresponding torque. Thus, by finding the correspondence between the engine speed and the response torque, the clutch-on control system can determine the response torque that may cause a large reduction in the engine speed at the current speed.

Further, considering that atmospheric pressure may change the energy conversion efficiency of the engine, in some other implementations, the effect of atmospheric pressure may also be considered in determining the response torque.

Specifically, a technician may test the output characteristics of the engine in advance to obtain the correspondence between the engine speed and the response torque under different atmospheric pressures. During operation of the clutch closure control system, a barometer may be used to make measurements or to obtain the current barometric pressure directly from the network or other control system. The response torque is then determined based on the current barometric pressure and the current rotational speed of the engine. Thus, the atmospheric pressure dimension is increased on the basis of the engine speed, and the obtained response torque is more accurate.

S103: and when the command torque of the engine is larger than or equal to the response torque, correcting the first command torque according to the command torque of the engine and the response torque to obtain a second command torque of the clutch.

After the response torque is obtained, the clutch closure control system may compare the magnitude of the command torque and the response torque of the engine. When the command torque of the engine is smaller than the response torque, the output torque of the engine is smaller at the moment, and the closing degree of the clutch is looser or the required torque of the power output shaft is lower; in this case, the clutch may be controlled to be closed directly based on the first command torque without correcting the first command torque of the clutch. When the command torque of the engine is greater than or equal to the response torque, the clutch control system may correct the first command torque according to the command torque of the engine and the response torque to obtain a second command torque smaller than the first command torque, so as to slow down a trend of a command torque of the clutch rising.

Wherein the first commanded torque of the clutch corresponds to a commanded torque of the clutch for controlling clutch closure without employing additional phase corrections. When no correction is applied, the commanded torque of the clutch should rise rapidly after the clutch begins to close, as shown by the dashed line in FIG. 2, indicating that the clutch closing speed is faster when no correction is applied. The corrected second command torque rises slowly after the clutch begins to close, as shown by the solid line in fig. 2, at a much slower rate than the first command torque, indicating that the clutch closing rate is slower after the correction. Therefore, the rising trend of the command torque of the clutch after correction is slowed down, and sufficient time is provided for the output power of the engine to be increased to the output power required by the power output shaft. Therefore, the engine can gradually increase the output torque while maintaining a high rotating speed so as to meet the requirement of the power output shaft.

Further, the clutch closure control system may periodically modify the first commanded torque. Thus, when the first command torque of the clutch in the current period is corrected, the second command torque of the previous period can be referred to. Therefore, the first instruction torque is corrected by integrating the instruction torque, the response torque and the second instruction torque of the previous period of the engine, and the obtained second instruction torque is more consistent with the current working state of the engine, so that the rotating speed of the engine is more favorably maintained.

In some possible implementations, the first command torque may also be corrected using a degree to which a command torque of the engine is greater than the response torque. The clutch closure control system may subtract or divide the commanded torque and the response torque of the engine to obtain a torque bias factor that may be indicative of the extent to which the commanded torque is greater than the response torque of the engine. Then, a first torque variation is calculated according to the difference value of the second instruction torque of the previous period and the response torque. And calculating to obtain a second torque variation according to the torque deviation coefficient and the first torque variation. And finally, calculating to obtain the second instruction torque of the period according to the second torque variation and the second instruction torque of the previous period. Thus, the greater the degree to which the command torque of the engine is greater than the response torque, the greater the resulting torque deviation factor, and the greater the correction strength for the first command torque. Therefore, even if the rising speed of the output power of the engine is slow, the obtained second command torque can still adapt to the change speed of the output power of the engine, so that the closing time of the clutch is prolonged, more time is provided for the engine to rise the output power, and the engine can be further ensured to maintain a high rotating speed when the output torque is gradually increased.

S104: and controlling the clutch to close according to the second command torque.

After the first command torque is corrected, the clutch closing control system can control the clutch main driving disc and the clutch auxiliary driving disc to be closed according to the obtained second command torque, and the engine can normally output power to the clutch, so that the power is output outwards.

The embodiment provides a clutch self-adaptive control method, which can acquire the current rotating speed of an engine, the command torque of the engine and the first command torque of a clutch, and determine the response torque which can cause the rotating speed of the engine to be remarkably reduced at the current rotating speed according to the current rotating speed; when the command torque of the engine is larger than the response torque, correcting the first command torque according to the command torque of the engine and the response torque to obtain a second command torque, and finally controlling the clutch to be closed according to the second command torque; it can be seen that when the engine is about to be towed to a lower speed, the speed at which the clutch is closed is slowed, thereby increasing the time required for the clutch to close, and providing sufficient time for the output power of the engine to increase to the required power. At this in-process, the actual output torque of engine can adapt to the instruction moment of torsion of clutch gradually, can not be dragged to lower rotational speed, so, the engine can be kept improving output torque gradually when higher rotational speed to satisfy the demand of the instruction moment of torsion of clutch, thereby avoid the driver to feel and frustrate, promote and drive and experience, can also improve the life of engine simultaneously.

Considering that the method provided by the above embodiment will reduce the speed at which the clutch closes, the time required for the clutch to close is longer, during which the engine cannot provide sufficient torque to the clutch. If the torque requirements of the component powered by the clutch are severe, the component may not function properly until the clutch is fully closed. For this case, one or more electric motors may be additionally added to the powertrain to make up for the torque differential during clutch closure.

Referring to fig. 3, the engine M is connected to the shaft a via a clutch, the motor EM is connected to the shaft C, and the shaft a and the shaft C are connected to the power take-off shaft B via a gear train. Since the motor output torque is easily adjusted, in this case, the clutch closure control system may obtain a compensation torque based on the difference between the first command torque and the second command torque, and then control the motor to output in accordance with the compensation torque. In this manner, the motor and the engine may simultaneously provide torque to the power take-off shaft. During the clutch closing process, although the second command torque actually output by the clutch is smaller than the first command torque output by the power output shaft demand clutch, the difference between the first command torque and the second command torque can be compensated by the electric motor. Since the motor output torque is easy to control and can be changed rapidly, sufficient torque can be provided to meet the demand of the power output shaft.

It should be specifically noted that fig. 3 is only a preferred embodiment of the adaptive control method for the clutch provided by the present application, and does not represent all technical solutions of the present application.

The foregoing provides some specific implementation manners of the adaptive clutch control method for the embodiments of the present application, and based on this, the present application also provides a corresponding apparatus. The above-mentioned device provided by the embodiments of the present application will be described in terms of functional modularity.

Referring to the schematic structure of the adaptive control apparatus for a clutch shown in fig. 4, the apparatus 400 includes:

an obtaining module 410 obtains a current speed of the engine, a commanded torque of the engine, and a first commanded torque of the clutch.

And the response determining module 420 is configured to determine a response torque corresponding to the current rotation speed according to the corresponding relationship between the engine rotation speed and the response torque.

And a correction calculation module 430, configured to correct the first command torque according to the command torque of the engine and the response torque when the command torque of the engine is greater than or equal to the response torque, so as to obtain a second command torque of the clutch, where the second command torque is smaller than the first command torque.

A close control module 440 to control the clutch to close based on the second commanded torque.

The embodiment provides a clutch self-adaptive control device, which can acquire the current rotating speed of an engine, the command torque of the engine and the first command torque of a clutch, and determine the response torque which can cause the rotating speed of the engine to be remarkably reduced at the current rotating speed according to the current rotating speed; when the command torque of the engine is larger than the response torque, correcting the first command torque according to the command torque of the engine and the response torque to obtain a second command torque, and finally controlling the clutch to be closed according to the second command torque; it can be seen that when the engine is about to be towed to a lower speed, the speed at which the clutch is closed is slowed, thereby increasing the time required for the clutch to close, and providing sufficient time for the output power of the engine to increase to the required power. At this in-process, the actual output torque of engine can adapt to the instruction moment of torsion of clutch gradually, can not be dragged to lower rotational speed, so, the engine can be kept improving output torque gradually when higher rotational speed to satisfy the demand of the instruction moment of torsion of clutch, thereby avoid the driver to feel and frustrate, promote and drive and experience, can also improve the life of engine simultaneously.

Optionally, the response determination module 420 is configured to obtain a current atmospheric pressure; and determining the response torque corresponding to the current rotating speed and the current atmospheric pressure according to the corresponding relation among the atmospheric pressure, the rotating speed of the engine and the response torque, so that the atmospheric pressure dimension is increased on the basis of the rotating speed of the engine, and the obtained response torque is more accurate.

Optionally, the correction calculation module 430 is configured to correct the first command torque according to the command torque of the engine, the response torque, and the second command torque of the previous period, so as to obtain a second command torque, and thus, the command torque, the response torque, and the second command torque of the previous period of the engine are combined to correct the first command torque, and the obtained second command torque better conforms to the current working state of the engine, which is more beneficial to maintaining the engine speed.

Optionally, referring to fig. 5, on the basis of the apparatus shown in fig. 4, the modification calculating module 430 includes:

a deviation calculation module 431 for calculating a torque deviation factor from the commanded torque and the response torque of the engine, the torque deviation factor representing a degree to which the commanded torque is greater than the response torque of the engine.

The first variation calculating module 432 is configured to calculate a first torque variation according to a difference between the second command torque of the previous cycle and the response torque.

And a second variation calculating module 433, configured to calculate a second torque variation according to the torque deviation coefficient and the first torque variation.

And the instruction calculating module 434 is configured to calculate the second instruction torque in the present period according to the second torque variation and the second instruction torque in the previous period.

Therefore, even if the torque response of the engine is poor, the obtained second command torque can still adapt to the torque change speed of the engine, so that the clutch closing time is prolonged, more time is provided for the engine to increase the output power, and the engine can be further ensured to maintain a higher rotating speed when the output torque is gradually increased.

Alternatively, referring to fig. 6, when the power output shaft connected to the clutch is also connected to the motor, the apparatus 400 further includes, in addition to the apparatus shown in fig. 5:

and the compensation calculating module 450 is configured to obtain a compensation torque according to a difference between the first command torque and the second command torque.

A motor control module 460 for controlling the motor to output in accordance with the compensated torque.

In this manner, the motor and the engine may simultaneously provide torque to the power take-off shaft. During the clutch closing process, although the second command torque actually output by the clutch is smaller than the first command torque output by the power output shaft demand clutch, the difference between the first command torque and the second command torque can be compensated by the electric motor. Since the motor output torque is easy to control and can be changed rapidly, sufficient torque can be provided to meet the demand of the power output shaft.

As can be seen from the above description of the embodiments, those skilled in the art can clearly understand that all or part of the steps in the above embodiment methods can be implemented by software plus a general hardware platform. Based on such understanding, the technical solution of the present application may be embodied in the form of a software product, which may be stored in a storage medium, such as a read-only memory (ROM)/RAM, a magnetic disk, an optical disk, or the like, and includes several instructions for enabling a computer device (which may be a personal computer, a server, or a network communication device such as a router) to execute the method according to the embodiments or some parts of the embodiments of the present application.

The embodiments in the present specification are described in a progressive manner, and the same and similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments. In particular, for the apparatus embodiment, since it is substantially similar to the method embodiment, it is relatively simple to describe, and reference may be made to some descriptions of the method embodiment for relevant points. The above-described apparatus and system embodiments are merely illustrative. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment. One of ordinary skill in the art can understand and implement it without inventive effort.

The above description is only an exemplary embodiment of the present application, and is not intended to limit the scope of the present application.

Claims

1. A method of adaptive clutch control, the method comprising:

and controlling the clutch to close according to the second command torque.

2. The method of claim 1, wherein said determining a response torque corresponding to said current speed based on a correspondence between engine speed and response torque comprises:

acquiring current atmospheric pressure;

3. The method of claim 1, wherein said modifying the first commanded torque based on the commanded torque of the engine and the response torque to obtain the second commanded torque of the clutch comprises:

4. The method of claim 3, wherein modifying the first commanded torque based on the commanded torque of the engine, the response torque, and the second commanded torque from the previous cycle to obtain the second commanded torque comprises:

5. The method of claim 1, wherein when the power take-off shaft coupled to the clutch is also coupled to an electric motor, the method further comprises:

and controlling the motor to output according to the compensation torque.

6. A clutch adaptation control apparatus, the apparatus comprising:

7. The apparatus of claim 6, wherein the response determination module is configured to obtain a current barometric pressure; and determining response torque corresponding to the current rotating speed and the current atmospheric pressure according to the corresponding relation among the atmospheric pressure, the engine rotating speed and the response torque.

8. The apparatus of claim 6, wherein the correction calculation module is configured to correct the first command torque based on a command torque of the engine, the response torque, and a second command torque of a previous cycle to obtain a second command torque.

9. The apparatus of claim 6, wherein the revision computation module comprises:

10. The apparatus of claim 6, wherein when the power take-off shaft connected to the clutch is further connected to an electric motor, the apparatus further comprises: