CN-117469387-B - Gear selection self-learning method and device for automatic transmission of wet clutch

CN117469387BCN 117469387 BCN117469387 BCN 117469387BCN-117469387-B

Abstract

The application discloses a gear selection self-learning method and device of an automatic transmission of a wet clutch, wherein the method comprises the steps of determining theoretical displacement of each position in a gear selection executing mechanism and theoretical total stroke of a gear selection sliding block; the method comprises the steps of carrying out first gear selection operation under the preset state of an electromagnet, if the difference between the actual displacement of the last position in the first gear selection operation and the actual displacement of the first position is larger than or equal to a theoretical total stroke, self-learning to control the relation among pulse width modulation signals, power supply voltage and current of the electromagnet, determining the optimal state of the electromagnet according to a self-learning result, obtaining the carefully chosen displacement of all positions based on a current-displacement relation curve obtained by carrying out second gear selection operation under the optimal state, carrying out gear engagement operation based on the carefully chosen displacement, and if the gear engagement operation of all positions is successful, taking the carefully chosen displacement of each position as a corresponding displacement set value. The application can rapidly and accurately select the correct and proper gear selection position displacement point.

Inventors

CHEN JIACHAO
ZHANG YOUHUANG
QI WEN
DAI DONGHUA
WANG YE
ZHANG JING

Assignees

安徽江淮汽车集团股份有限公司

Dates

Publication Date: 20260512
Application Date: 20231117

Claims (9)

1. A method of self-learning a gear selection for a wet clutch automatic transmission, comprising: determining theoretical displacement of each position in a gear selecting executing mechanism and theoretical total stroke of a gear selecting sliding block according to the structure and the characteristics of a gear selecting system of the automatic wet clutch transmission, wherein the theoretical total stroke is the difference between the theoretical displacement of the last position and the theoretical displacement of the first position; performing a first gear selecting operation when the electromagnet is in a preset state; If the difference between the actual displacement of the last position and the actual displacement of the first position in the first gear selecting operation is greater than or equal to the theoretical total stroke, self-learning the relation among the pulse width modulation signal, the power supply voltage and the current of the control electromagnet; Determining a preferred state of the electromagnet according to a self-learning result, and obtaining carefully chosen displacements of all positions based on a current-displacement relation curve obtained by performing a second gear selection operation in the preferred state, wherein the self-learning result comprises a corresponding relation among a pulse width modulation signal, a power supply voltage and a current of the control electromagnet, and specifically comprises the steps of preliminarily determining the relation between the pulse width modulation signal and the power supply voltage under the condition of keeping the current linearly changed based on historical data; Performing a shift operation based on the pick displacement; And if the gear engaging operation of all the positions is successful, selecting displacement of each position as a corresponding displacement setting value.
2. The method for self-learning gear selection of a wet clutch automatic transmission according to claim 1, wherein the preset state is a pulse width modulation signal of controlling an electromagnet is 100%, and a power supply voltage is a maximum value.
3. The method for self-learning gear selection of a wet clutch automatic transmission according to claim 1, wherein selecting displacements of all positions is obtained based on a current-displacement relationship curve obtained by performing a second gear selection operation in the preferred state, specifically comprising: determining initial displacement values of all positions according to the current-displacement relation curve; the corresponding pick displacements are determined based on the initial displacement values of the respective positions and the corresponding pick design tolerances.
4. The method for self-learning gear selection of an automatic wet clutch transmission according to claim 1, wherein the step of performing an actual operation to confirm the relationship between the pwm signal and the supply voltage to obtain a correspondence between the pwm signal, the supply voltage and the current, comprises: On the basis of an initial state, keeping a pulse width modulation signal unchanged, adjusting a power supply voltage in a gradient manner, and keeping the current linearly changed; and simultaneously adjusting the supply voltage and the pulse width modulation signal based on the relation between the pulse width modulation signal and the supply voltage, so that the current continues to linearly change until the corresponding relation between all the supply voltages and all the pulse width modulation signals is determined.
5. The gear selection self-learning device of the wet clutch automatic transmission is characterized by comprising a theoretical parameter determining module, a first gear selection operation module, a self-learning module, a selection displacement obtaining module, a gear engagement operation module and a confirmation module; The theoretical parameter determining module is used for determining theoretical displacement of each position in the gear selecting executing mechanism and theoretical total stroke of the gear selecting sliding block according to the structure and the characteristics of a gear selecting system of the automatic wet clutch transmission, wherein the theoretical total stroke is the difference between the theoretical displacement of the last position and the theoretical displacement of the first position; The first gear selecting operation module is used for performing first gear selecting operation when the electromagnet is in a preset state; the self-learning module is used for self-learning the relation among pulse width modulation signals, power supply voltage and current of the control electromagnet when the difference between the actual displacement of the last position and the actual displacement of the first position in the first gear selection operation is greater than or equal to the theoretical total stroke; The selection displacement obtaining module is used for determining the preferred state of the electromagnet according to a self-learning result and obtaining selection displacements of all positions based on a current-displacement relation curve obtained by performing second gear selection operation in the preferred state, wherein the self-learning result comprises a corresponding relation among a pulse width modulation signal, a power supply voltage and a current of the control electromagnet, and concretely comprises the steps of preliminarily determining the relation between the pulse width modulation signal and the power supply voltage under the condition of keeping the current to linearly change based on historical data; the gear-shifting operation module is used for performing gear-shifting operation based on the carefully selected displacement; And the confirmation module is used for taking the carefully selected displacement of each position as a corresponding displacement set value when the gear engaging operation of all the positions is successful.
6. The gear-selecting self-learning device of a wet clutch automatic transmission according to claim 5, wherein the preset state is that a pulse width modulation signal of the control electromagnet is 100%, and a power supply voltage is a maximum value.
7. The automatic transmission gear selection self-learning device of claim 5 wherein the pick displacement acquisition module comprises an initial value determination module and a pick displacement determination module; The initial value determining module is used for determining the initial value of the displacement of each position according to the current-displacement relation curve; The selection displacement determining module is used for determining corresponding selection displacement based on the initial displacement value of each position and the corresponding selection design tolerance.
8. The automatic transmission gear selection self-learning device of claim 5 wherein the self-learning module comprises a preliminary determination module and an actual operation confirmation module; the preliminary determination module is used for preliminarily determining the relation between the pulse width modulation signal and the power supply voltage under the condition of keeping the linear change of the current based on historical data; The real operation confirming module is used for carrying out real operation confirmation on the relation between the pulse width modulation signal and the power supply voltage to obtain the corresponding relation among the pulse width modulation signal, the power supply voltage and the current.
9. The automatic transmission gear selection self-learning device of claim 8 wherein the actual operation confirmation module comprises a first adjustment module and a second adjustment module; the first adjusting module is used for keeping the pulse width modulation signal unchanged, adjusting the power supply voltage in a gradient mode and keeping the current to change linearly on the basis of an initial state; The second adjusting module is used for simultaneously adjusting the power supply voltage and the pulse width modulation signal based on the relation between the pulse width modulation signal and the power supply voltage, so that the current continues to linearly change until the corresponding relation between all the power supply voltages and all the pulse width modulation signals is determined.

Description

Gear selection self-learning method and device for automatic transmission of wet clutch Technical Field The application relates to the technical field of gearboxes, in particular to a gear selection self-learning method and device of an automatic wet clutch transmission. Background An automatic gearbox gear selection executing mechanism of an electronic control mechanical automatic gearbox (Automatic Mechanical Transmission, AMT) in the current commercial vehicle market mainly provides a power source through hydraulic pressure, air pressure or a motor. Along with the development trend of dynamoelectric, hydraulic pressure and air pressure are gradually eliminated, and the motor gear shifting has better control precision but lower efficiency. Under the application requirement of commercial vehicles, part of wet clutch automatic transmissions adopt electromagnet gear shifting, thereby not only conforming to the trend of electrodynamic property, but also improving the efficiency and reducing the cost. As shown in fig. 1, the gear selection system of the wet clutch automatic transmission includes a gear selection actuator having four positions (positions 1-4) which are position-distinguished by springs (e.g., springs 40-60) having different stiffness coefficients, a displacement sensor 20, and an electromagnet 10. The gear selection control target is to quickly and accurately control the gear selection sliding block 30 to realize corresponding position displacement according to gear selection requirements, and meanwhile, the output moment of the electromagnet 10 is strongly related to the displacement, so that the accuracy of the four position displacements is the key for achieving the gear shifting target. Because the gear selection position displacement achieves the target accuracy and is influenced by the execution structure, the displacement sensor and the output torque error of the electromagnet, the gear selection position displacement is required to be learned by a combination system. However, in the existing learning, only related hardware errors are learned, and the influence of errors in power source control cannot be considered. Disclosure of Invention The application provides a gear selection self-learning method and device of a wet clutch automatic transmission, which are used for controlling the current change of an electromagnet in the gear selection process based on the relation among a pulse width modulation signal, a power supply voltage and a current of a control electromagnet obtained by self-learning, so that a correct and proper gear selection position displacement point is quickly and accurately selected, the software control precision is improved, and the accurate gear selection displacement can also ensure the state of the wet clutch automatic transmission and the off-line state of the whole vehicle as well as consistency, reliability, safety and stability. The application provides a gear selection self-learning method of an automatic transmission of a wet clutch, which comprises the following steps: Determining theoretical displacement of each position in a gear selecting executing mechanism and theoretical total stroke of a gear selecting sliding block according to the structure and the characteristics of a gear selecting system of the automatic wet clutch transmission, wherein the theoretical total stroke is the difference between the theoretical displacement of the last position and the theoretical displacement of the first position; performing a first gear selecting operation when the electromagnet is in a preset state; If the difference between the actual displacement of the last position and the actual displacement of the first position in the first gear selecting operation is larger than or equal to the theoretical total stroke, self-learning the relation among the pulse width modulation signal, the power supply voltage and the current of the control electromagnet; determining the preferred state of the electromagnet according to the self-learning result, and obtaining the carefully chosen displacement of all positions based on a current-displacement relation curve obtained by performing the second gear selection operation in the preferred state; performing a shift operation based on the pick displacement; And if the gear engaging operation of all the positions is successful, selecting displacement of each position as a corresponding displacement setting value. Preferably, the preset state is that the pulse width modulation signal controlling the electromagnet is 100% and the supply voltage is the maximum value. Preferably, the selected displacement of all positions is obtained based on a current-displacement relation curve obtained by performing the second gear selection operation in the preferred state, specifically including: Determining the displacement initial value of each position according to the current-displacement relation curve; the corresponding pick displacements a