阅读说明：本技术 干式双离合器半结合点自学习方法 (Self-learning method for half-joint points of dry type double clutches ) 是由 黄斌 刘拂晓 李育 高晶 田维伟 于 2019-04-23 设计创作，主要内容包括：一种干式双离合器半结合点自学习方法,通过获取传感器信号实时判断车辆工况,当发动机扭矩、转速的变化率均小于给定值时认定扭矩和转速进入稳定状态,则启动自学习过程：设定离合器流量阀为固定电流,再设定离合器压力阀以恒定电流完成预充过程,然后调整压力阀电流并记录在自学习状态下的输入轴转速,对转速进行滤波处理后计算其变化率,得到转速及其变化率与离合器实际位置的对应图,并通过识别图中的突变点位置即为达到离合器半结合点位置。(A dry type double clutch semi-combination point self-learning method comprises the steps of judging vehicle working conditions in real time by obtaining sensor signals, determining that torque and rotating speed enter a stable state when the change rates of the torque and the rotating speed of an engine are smaller than given values, and starting a self-learning process: setting a flow valve of the clutch as a fixed current, then setting a pressure valve of the clutch to finish a pre-charging process by a constant current, then adjusting the current of the pressure valve and recording the rotating speed of an input shaft in a self-learning state, carrying out filtering processing on the rotating speed and then calculating the change rate of the rotating speed to obtain a corresponding graph of the rotating speed and the change rate and the actual position of the clutch, and identifying the position of a break point in the graph to be the position reaching the half-joint point of the clutch.)

1. A dry-type double-clutch semi-combination point self-learning method is characterized in that the working condition of a vehicle is judged in real time by acquiring sensor signals, and when the change rates of the torque and the rotating speed of an engine are smaller than given values, the torque and the rotating speed are determined to enter a stable state, and a self-learning process is started: setting a flow valve of the clutch as a fixed current, then setting a pressure valve of the clutch to finish a pre-charging process by a constant current, then adjusting the current of the pressure valve and recording the rotating speed of an input shaft in a self-learning state, carrying out filtering processing on the rotating speed and then calculating the change rate of the rotating speed to obtain a corresponding graph of the rotating speed and the change rate and the actual position of the clutch, and identifying the position of a break point in the graph to be the position reaching the half-joint point of the clutch.

2. The method of claim 1, wherein the fixed current is half the maximum current.

3. The method of claim 1, wherein the priming process is: when the pressure valve current is constant, the clutch moves towards the joint point under constant pressure until the set position is reached.

4. The method of claim 3, wherein the set positions are: not yet but close to the location of the binding site.

5. The method of claim 1, wherein said adjusting the pressure valve current is: when the clutch reaches a set position, the pressure valve current is increased from the dead band current at a fixed rate to move the driven plate of the clutch toward the driving plate.

6. The method of claim 1, wherein the filtering process is: the method comprises the following steps of adopting first-order filtering processing on the rotation speed of an input shaft from a sensor to prevent false detection caused by signal jump, specifically, y (k) ═ 1-alpha (k-1) + alpha x (k), wherein: k is a natural number larger than 0, alpha is a filter coefficient (alpha is more than or equal to 0 and less than or equal to 1), x (k) is an input quantity, y (k) is an output quantity at the current moment, and y (k-1) is an output quantity at the last moment.

7. The method of claim 1, wherein said half-bond locations are: and when the rotating speed of the input shaft and the change rate of the rotating speed reach set values, the corresponding position of the clutch sensor.

Technical Field

The invention relates to a technology in the field of clutch joint self-learning, in particular to a dry type double-clutch half joint self-learning method.

Background

The dry type dual-clutch transmission is popular in the market due to the advantages of good fuel economy, smooth gear shifting and the like. However, the dry-type dual clutch is sensitive to complex working conditions and greatly affected by external environments, and the like, so that great control difficulty is caused. Therefore, in order to ensure good dynamic performance and driving comfort of the vehicle, the control level of the clutch needs to be improved as much as possible, especially the torque transmission characteristic of the clutch is the key of the clutch position control, and the half-joint point of the clutch is the actual position corresponding to the initial moment of torque transmission, which is an extremely important target state in the control process and must be accurately identified. The clutch is combined and separated by the action of hydraulic oil in the accumulator on the connected hydraulic main cylinder through a pressure valve and a flow valve.

Disclosure of Invention

Aiming at the blank existing in the prior art, the invention provides a self-learning method for the semi-joint points of the dry type double clutch, which can automatically identify the positions of the semi-joint points.

The invention is realized by the following technical scheme:

the invention judges the vehicle working condition in real time by acquiring the sensor signal, and determines that the torque and the rotating speed enter a stable state when the change rates of the torque and the rotating speed of the engine are both smaller than the given values, and then starts a self-learning process: setting a flow valve of the clutch as a fixed current, then setting a pressure valve of the clutch to finish a pre-charging process by a constant current, then adjusting the current of the pressure valve and recording the rotating speed of an input shaft in a self-learning state, carrying out filtering processing on the rotating speed and then calculating the change rate of the rotating speed to obtain a corresponding graph of the rotating speed and the change rate and the actual position of the clutch, and identifying the position of a break point in the graph to be the position reaching the half-joint point of the clutch.

The fixed current is preferably half the maximum current.

The pre-charging process comprises the following steps: when the pressure valve current is constant, the clutch moves towards the joint point under constant pressure until the set position is reached.

The set position is not yet but close to the position of the binding point.

The current adjustment is to increase the pressure valve current at a fixed rate from the dead zone current after the clutch reaches a set position, so that the driven disc of the clutch moves toward the driving disc.

The input shaft rotating speed filtering means that: the method adopts first-order filtering processing to the rotation speed of an input shaft from a sensor to prevent false detection caused by signal jump, and the specific formula is (1-alpha) y (k-1) + alpha x (k). In the formula, k is a natural number larger than 0, α is a filter coefficient (0 ≦ α ≦ 1), x (k) is an input quantity, y (k) is an output quantity at the current time, and y (k-1) is an output quantity at the previous time.

The filter coefficient is selected according to the precision of the used rotating speed sensor, and the smaller the value of the filter coefficient is, the better the filter effect is represented, but the truth degree is lower.

The half-binding point position refers to that: and when the rotating speed of the input shaft and the change rate of the rotating speed reach set values, the corresponding position of the clutch sensor.

Technical effects

Compared with the prior art, the invention aims at the dry type double-clutch transmission, when the gear shift lever is in a P gear state, the engine is started and all the shifting forks are in a neutral gear state, the pressure valve and the flow valve are controlled, the clutch completes the designated action according to the flow, the rotating speed state of the input shaft is detected in real time, the position of a half-combination point is automatically identified, the whole learning process is simple to operate, the accuracy of the learning result is high, the consistency is good, and the full verification of a rack and a real vehicle is obtained.

Drawings

FIG. 1 is a schematic view of the present invention;

fig. 2 is a schematic diagram of pressure valve current control.

Detailed Description

As shown in FIG. 1, the engine is started in the vehicle static state, and the clutch engagement point (KissPoint) self-learning process is started, and the specific steps are as follows:

1) entering self-learning conditions:

1.1) the gear shifting lever is positioned at a P gear position;

1.2) placing a shifting fork at a neutral position;

1.3) the brake pressure is larger than a fixed value;

1.4) the engine is in a running state, and the rotating speed is stable;

1.5) the torque of the engine is stabilized;

2) the self-learning process comprises the following steps:

2.1) setting the current of the flow valve of the clutch as a fixed value to ensure a constant flow;

2.2) setting the current of the pressure valve of the clutch as a fixed value, ensuring that the clutch moves towards the direction of the joint point with constant pressure until reaching a set position which is a position which does not reach the joint point;

2.3) adjusting the current of the pressure valve to increase from the dead zone current at a fixed rate to push a driven disc of the clutch to move towards a driving disc;

2.4) detecting the rotating speed and the rotating speed change rate of the input shaft corresponding to the clutch in the steps 2.1) to 2.3) in real time, and recording the position of the clutch at the moment when the rotating speed and the change rate of the input shaft reach set values, wherein the position is the position of a binding point;

and 2.5) after the position of the binding point is recorded, setting the current of the pressure valve to be zero, and finishing self-learning.

As shown in FIG. 2, the pressure valve current control is illustrated schematically, and during the plateau period, the clutch is pre-charged to l₁Constant current at position, ramp-up period being clutch from₁Position is moved to₂The control current at the position (half-junction point position) is 0 current after the self-learning is finished in the falling period.

The foregoing embodiments may be modified in many different ways by those skilled in the art without departing from the spirit and scope of the invention, which is defined by the appended claims and all changes that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.