阅读说明：本技术 一种湿式离合器的润滑控制方法、装置及车辆 (Lubrication control method and device of wet clutch and vehicle ) 是由 裴玲 仇杰 虞璐伊 张涛 王晓伟 陈亮 于 2019-10-16 设计创作，主要内容包括：本申请公开了一种湿式离合器的润滑控制方法、装置及车辆。该方法确定湿式离合器的期望润滑流量对应的润滑流量区间,所述润滑流量区间的数量包括至少两个,所述至少两个润滑流量区间分别对应有目标润滑流量；根据确定的所述润滑流量区间对应的目标润滑流量,控制润滑油泵工作,以使所述润滑油泵的转速与所述目标润滑流量对应。该方法采用分段润滑策略,将润滑油泵的转速从全转速范围,变成了与至少两个目标润滑流量对应的特定转速,进而减少或避免润滑油泵在全转速范围内工作时,由于共振引起的NVH问题。(The application discloses a lubrication control method and device of a wet clutch and a vehicle. The method comprises the steps of determining a lubrication flow interval corresponding to expected lubrication flow of a wet clutch, wherein the number of the lubrication flow intervals comprises at least two, and the at least two lubrication flow intervals respectively correspond to target lubrication flow; and controlling the lubricating oil pump to work according to the determined target lubricating flow corresponding to the lubricating flow interval so as to enable the rotating speed of the lubricating oil pump to correspond to the target lubricating flow. The method adopts a sectional lubrication strategy, changes the rotating speed of the lubricating oil pump from a full rotating speed range to a specific rotating speed corresponding to at least two target lubricating flows, and further reduces or avoids NVH (noise, vibration and harshness) problems caused by resonance when the lubricating oil pump works in the full rotating speed range.)

1. A lubrication control method of a wet clutch, comprising:

determining a lubrication flow interval corresponding to an expected lubrication flow of a wet clutch, wherein the number of the lubrication flow intervals comprises at least two, and the at least two lubrication flow intervals respectively correspond to target lubrication flows;

and controlling the lubricating oil pump to work according to the determined target lubricating flow corresponding to the lubricating flow interval so as to enable the rotating speed of the lubricating oil pump to correspond to the target lubricating flow.

2. The method of claim 1, wherein the at least two lubrication flow intervals and their corresponding target flow intervals are determined according to NVH experimental results of the lubrication oil pump.

3. The method as claimed in claim 1, wherein the rotation speed range of the lubrication oil pump corresponding to the target lubrication flow rate does not overlap with a rotation speed range when resonance is generated due to rotation of the lubrication oil pump.

4. The method of claim 1, wherein prior to said determining a lubrication flow interval corresponding to a desired lubrication flow of a wet clutch, the method further comprises:

and if the wet clutch is in a slipping state, determining the expected lubricating flow according to the slipping power of the wet clutch.

5. The method of claim 4, further comprising: and if the wet clutch is not in the friction sliding state, controlling the lubricating oil pump to work according to the lubricating oil leakage rate.

6. The method of claim 4, wherein the determining the desired lubrication flow from the slip power of the wet clutch comprises:

and determining the expected lubricating flow according to the sliding friction power of the wet clutch and the lubricating oil temperature of the wet clutch.

7. The method of claim 1, wherein the target lubrication flow for the lubrication flow interval comprises: and the upper limit value of the lubricating flow interval.

8. The method as claimed in claim 1, wherein the controlling of the operation of the lubricating oil pump according to the determined target lubricating flow rate corresponding to the lubricating flow rate interval comprises:

and determining the control lubrication flow output by the controller in the current period according to the final control lubrication flow output by the controller in the last period and the current target lubrication flow, so as to control the lubricating oil pump to work through the control lubrication flow.

9. The method of claim 8, wherein determining the control lubrication flow output by the controller during the current period based on the final control lubrication flow output by the controller during the previous period and the current target lubrication flow comprises:

if the current target lubrication flow is larger than the final control lubrication flow of the previous period, determining that the control lubrication flow output by the controller in the current period is equal to the current target lubrication flow;

or if the current target lubrication flow is smaller than the final control lubrication flow of the previous period, determining that the control lubrication flow output by the controller in the current period is gradually reduced from the final control lubrication flow of the previous period to the current target lubrication flow;

or, if the current target lubrication flow is equal to the final control lubrication flow of the previous period, determining that the control lubrication flow output by the controller in the current period is equal to the final control lubrication flow of the previous period.

10. A lubrication control device for a wet clutch, comprising:

the interval determination module is used for determining a lubrication flow interval corresponding to expected lubrication flow of the wet clutch, the number of the lubrication flow intervals comprises at least two, and the at least two lubrication flow intervals respectively correspond to target lubrication flow;

and the interval control module is used for controlling the lubricating oil pump to work according to the determined target lubricating flow corresponding to the lubricating flow interval so as to enable the rotating speed of the lubricating oil pump to correspond to the target lubricating flow.

11. The apparatus of claim 10, wherein the at least two lubrication flow intervals and their corresponding target flow intervals are determined according to NVH experimental results of the lubrication oil pump.

12. The apparatus of claim 10, wherein a rotation speed range of the lubrication oil pump corresponding to the target lubrication flow rate does not overlap with a rotation speed range when resonance is generated due to rotation of the lubrication oil pump.

13. The apparatus of claim 10, further comprising:

and the expected flow determining module is used for determining the expected lubricating flow according to the friction power of the wet clutch if the wet clutch is in the friction state.

14. The apparatus of claim 13, further comprising:

and the speed control module is used for controlling the lubricating oil pump to work according to the lubricating oil leakage speed if the wet clutch is not in the friction sliding state.

15. The apparatus of claim 13, wherein the desired flow determination module is specifically configured to: and determining the expected lubricating flow according to the sliding friction power of the wet clutch and the lubricating oil temperature of the wet clutch.

16. The apparatus of claim 10, wherein the target lubrication flow for the lubrication flow interval comprises: and the upper limit value of the lubricating flow interval.

17. The apparatus of claim 10, wherein the interval control module comprises:

and the period control module is used for determining the control lubrication flow output by the controller in the current period according to the final control lubrication flow output by the controller in the last period and the current target lubrication flow, so as to control the lubricating oil pump to work through the control lubrication flow.

18. The apparatus of claim 17, wherein the period control module is specifically configured to:

if the current target lubrication flow is larger than the final control lubrication flow of the previous period, determining that the control lubrication flow output by the controller in the current period is equal to the current target lubrication flow;

or if the current target lubrication flow is smaller than the final control lubrication flow of the previous period, determining that the control lubrication flow output by the controller in the current period is gradually reduced from the final control lubrication flow of the previous period to the current target lubrication flow;

or, if the current target lubrication flow is equal to the final control lubrication flow of the previous period, determining that the control lubrication flow output by the controller in the current period is equal to the final control lubrication flow of the previous period.

19. A vehicle characterized by comprising a controller for executing the lubrication control method of a wet clutch according to any one of claims 1 to 9.

Technical Field

The application relates to the technical field of automobiles, in particular to a lubrication control method and device of a wet clutch and a vehicle.

Background

The flow rate of the lubricating oil required by the wet clutch changes along with the change of the working condition of the vehicle corresponding to the wet clutch. Generally, the rotating speed of the lubricating oil pump can be directly controlled according to the lubricating flow required by the wet clutch, so as to meet the requirement of the wet clutch on the lubricating flow. But this requires the brushless dc motor in the lubrication pump to operate continuously over the full speed range.

However, the brushless dc motor generates electromagnetic torque pulsation during operation, and the brushless dc motor continuously operates in a full rotation speed range, so that the frequency of the electromagnetic torque pulsation of the brushless dc motor is inevitably consistent with the mechanical resonance frequency of the stator and the rotor or the mechanical natural resonance frequency of the housing connected to the lubricating oil pump, so that noise caused by the electromagnetic torque pulsation is amplified due to resonance, which affects the operation performance of the lubricating oil pump, and thus causes NVH problem, which affects the performance of the vehicle in which the lubricating oil pump is located.

Disclosure of Invention

In view of the above problems, the present application provides a lubrication control method and apparatus for a wet clutch, and a vehicle, so as to reduce or avoid NVH caused by resonance when a lubrication oil pump operates in a full rotation speed range.

The embodiment of the application discloses the following technical scheme:

in a first aspect, the present application provides a lubrication control method of a wet clutch, including: determining a lubrication flow interval corresponding to an expected lubrication flow of a wet clutch, wherein the number of the lubrication flow intervals comprises at least two, and the at least two lubrication flow intervals respectively correspond to target lubrication flows; and controlling the lubricating oil pump to work according to the determined target lubricating flow corresponding to the lubricating flow interval so as to enable the rotating speed of the lubricating oil pump to correspond to the target lubricating flow.

Optionally, the at least two lubrication flow intervals and the corresponding target flow intervals are determined according to NVH experimental results of the lubrication oil pump.

Optionally, the rotation speed range of the lubricating oil pump corresponding to the target lubricating flow rate does not overlap with the rotation speed range when resonance is generated due to rotation of the lubricating oil pump.

Optionally, before the determining the lubrication flow interval corresponding to the desired lubrication flow of the wet clutch, the method further comprises: and if the wet clutch is in a slipping state, determining the expected lubricating flow according to the slipping power of the wet clutch.

Optionally, the method further comprises: and if the wet clutch is not in the friction sliding state, controlling the lubricating oil pump to work according to the lubricating oil leakage rate.

Optionally, the determining the desired lubrication flow from the wet clutch slip power comprises: and determining the expected lubricating flow according to the sliding friction power of the wet clutch and the lubricating oil temperature of the wet clutch.

Optionally, the target lubrication flow rate corresponding to the lubrication flow rate interval includes: and the upper limit value of the lubricating flow interval.

Optionally, the controlling the operation of the lubricating oil pump according to the determined target lubricating flow corresponding to the lubricating flow interval includes: and determining the control lubrication flow output by the controller in the current period according to the final control lubrication flow output by the controller in the last period and the current target lubrication flow, so as to control the lubricating oil pump to work through the control lubrication flow.

Optionally, the determining, according to the final control lubrication flow output by the controller in the last period and the current target lubrication flow, the control lubrication flow output by the controller in the current period includes: if the current target lubrication flow is larger than the final control lubrication flow of the previous period, determining that the control lubrication flow output by the controller in the current period is equal to the current target lubrication flow; or if the current target lubrication flow is smaller than the final control lubrication flow of the previous period, determining that the control lubrication flow output by the controller in the current period is gradually reduced from the final control lubrication flow of the previous period to the current target lubrication flow; or, if the current target lubrication flow is equal to the final control lubrication flow of the previous period, determining that the control lubrication flow output by the controller in the current period is equal to the final control lubrication flow of the previous period.

In a second aspect, the present application provides a lubrication control device of a wet clutch, comprising: the device comprises an interval determining module and an interval control module; the interval determination module is used for determining a lubrication flow interval corresponding to expected lubrication flow of the wet clutch, the number of the lubrication flow intervals comprises at least two, and the at least two lubrication flow intervals respectively correspond to target lubrication flow; and the interval control module is used for controlling the lubricating oil pump to work according to the determined target lubricating flow corresponding to the lubricating flow interval so as to enable the rotating speed of the lubricating oil pump to correspond to the target lubricating flow.

Optionally, the at least two lubrication flow intervals and the corresponding target flow intervals are determined according to NVH experimental results of the lubrication oil pump.

Optionally, the rotation speed range of the lubricating oil pump corresponding to the target lubricating flow rate does not overlap with the rotation speed range when resonance is generated due to rotation of the lubricating oil pump.

Optionally, the apparatus further comprises: and the expected flow determining module is used for determining the expected lubricating flow according to the friction power of the wet clutch if the wet clutch is in the friction state.

Optionally, the apparatus further comprises: and the speed control module is used for controlling the lubricating oil pump to work according to the lubricating oil leakage speed if the wet clutch is not in the friction sliding state.

Optionally, the expected flow determination module is specifically configured to: and determining the expected lubricating flow according to the sliding friction power of the wet clutch and the lubricating oil temperature of the wet clutch.

Optionally, the target lubrication flow rate corresponding to the lubrication flow rate interval includes: and the upper limit value of the lubricating flow interval.

Optionally, the interval control module includes: and the period control module is used for determining the control lubrication flow output by the controller in the current period according to the final control lubrication flow output by the controller in the last period and the current target lubrication flow, so as to control the lubricating oil pump to work through the control lubrication flow.

Optionally, the period control module is specifically configured to: if the current target lubrication flow is larger than the final control lubrication flow of the previous period, determining that the control lubrication flow output by the controller in the current period is equal to the current target lubrication flow; or if the current target lubrication flow is smaller than the final control lubrication flow of the previous period, determining that the control lubrication flow output by the controller in the current period is gradually reduced from the final control lubrication flow of the previous period to the current target lubrication flow; or, if the current target lubrication flow is equal to the final control lubrication flow of the previous period, determining that the control lubrication flow output by the controller in the current period is equal to the final control lubrication flow of the previous period.

In a third aspect, the present application provides a vehicle comprising a controller for executing the lubrication control method of a wet clutch as described above.

Compared with the prior art, the method has the following beneficial effects:

the application provides a wet clutch's lubrication control scheme, through from two at least lubrication flow intervals, it is regional to confirm the lubrication flow that expects the lubrication flow to correspond, thereby according to the regional work of target lubrication flow control lubricating oil pump that corresponds of lubrication flow confirmed, adopt the segmentation lubrication strategy promptly, with the rotational speed of lubricating oil pump from the full speed range, become the specific rotational speed that corresponds with two at least target lubrication flow, and then reduce or avoid lubricating oil pump when full speed within range work, because the NVH problem that resonance arouses.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments 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 that other drawings can be obtained according to the drawings without inventive exercise.

Fig. 1 is a flowchart of a lubrication control method for a wet clutch according to an embodiment of the present disclosure;

FIG. 2 is a flow chart illustrating another method for controlling lubrication of a wet clutch according to an embodiment of the present disclosure;

FIG. 3 is a flow chart illustrating another method for controlling lubrication of a wet clutch according to an embodiment of the present disclosure;

FIG. 4 is a schematic structural diagram of a lubricant pump according to an embodiment of the present disclosure;

fig. 5 is a schematic structural diagram of a lubrication control device of a wet clutch according to an embodiment of the present disclosure.

Detailed Description

As described above, in the current control system of the wet clutch, since the lubrication pump continuously operates in the full rotation speed range, the NVH problem may be caused.

Based on the above problems, the inventors have studied and provided a method and an apparatus for controlling lubrication of a wet clutch, and a vehicle. The method may be specifically executed by a transmission controller TCU in a vehicle. The lubricating flow interval corresponding to the expected lubricating flow is determined from the at least two lubricating flow intervals, so that the lubricating oil pump works according to the target lubricating flow corresponding to the determined lubricating flow interval, namely, a segmented lubricating strategy is adopted, the rotating speed of the lubricating oil pump is changed from a full rotating speed range to a specific rotating speed corresponding to the at least two target lubricating flows, and the NVH problem caused by resonance when the lubricating oil pump works in the full rotating speed range is further reduced or avoided.

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.

First embodiment

Referring to fig. 1, the figure is a flowchart of a lubrication control method of a wet clutch according to an embodiment of the present application.

As shown in fig. 1, the method for controlling lubrication of a wet clutch according to the present embodiment includes:

step 101: and determining a lubrication flow interval corresponding to the expected lubrication flow of the wet clutch.

First, an application scenario of the method is described. The lubrication control method of the wet clutch provided by the embodiment can be used for controlling the flow of lubricating oil of the wet clutch in a vehicle, and is mainly applied to a transmission controller TCU. In addition to the gearbox controller, other components may be included in the control system, such as wet clutches, lubrication oil pumps, etc. The lubricating oil pump may include a dc brushless motor and a mechanical pump. Of course, the control system may also include other components, and the types and the number of the components included in the control system are not limited herein.

It will be appreciated that the desired amount of lubrication flow for the wet clutch is related to, among other factors, the operating conditions of the vehicle in which the wet clutch is located and the friction surface of the wet clutch. For example, when the working condition of the vehicle is starting, large throttle gear shifting and the like, the expected lubricating flow of the wet clutch is large so as to maintain the heat balance state of the wet clutch through a large amount of lubricating oil; alternatively, when the friction surface temperature of the wet clutch is excessively high, the desired lubrication flow rate of the wet clutch is large to cool the friction surface by a large amount of lubrication oil.

In addition, the number of the lubrication flow intervals comprises at least two, and the at least two lubrication flow intervals are respectively corresponding to target lubrication flow.

The lubrication flow interval may be determined according to a total range of desired lubrication flow of the wet clutch. For example, if the total range of desired lubrication flow is (0, Q)_M]Then, the total range of the expected lubrication flow may be divided into at least two lubrication flow intervals, and the divided lubrication flow intervals may be:

(0，Q1]

(Q1，Q2]

(Q2，Q3]

(Q3，Q4]

……

(QM-1，QM]

the number of the specific divided lubrication flow intervals can be determined by those skilled in the art according to the needs, and the embodiment does not limit this.

Each lubrication flow interval corresponds to a target lubrication flow, the target lubrication flow corresponding to each lubrication flow interval may be one or multiple, the number of the target lubrication flows corresponding to different lubrication flow intervals may be the same or different, and this embodiment also does not limit this. At least two lubrication flow intervals and their corresponding target lubrication flow may be preset.

In this step, the desired wetting of the wet clutch is determinedThe lubrication flow rate section corresponding to the slip flow rate, that is, the lubrication flow rate section in which the value of the desired lubrication flow rate is located is determined from at least two lubrication flow rate sections, for example, the lubrication flow rate section in which the value of the desired lubrication flow rate is located can be determined as (Q) from the plurality of lubrication flow rate sections₃，Q₄]。

Step 102: and controlling the lubricating oil pump to work according to the determined target lubricating flow corresponding to the lubricating flow interval so as to enable the rotating speed of the lubricating oil pump to correspond to the target lubricating flow.

When the lubricating oil pump works according to the target lubricating flow control, the rotating speed of the lubricating oil pump can be controlled, so that the flow of the lubricating oil provided by the lubricating oil pump is consistent with the target lubricating flow, and at the moment, the rotating speed of the lubricating oil pump corresponds to the target lubricating flow of the determined lubricating flow interval.

Specifically, the control lubrication flow rate can be determined according to the target lubrication flow rate, and the control lubrication flow rate is transmitted to the lubrication oil pump through the transmission controller TCU, and the brushless dc motor in the lubrication oil pump rotates at the rotation speed corresponding to the control lubrication flow rate to supply energy to the mechanical pump in the lubrication oil pump, so that the mechanical pump pumps the lubrication oil to the lubrication oil pipe of the wet clutch according to the flow rate corresponding to the rotation speed of the brushless dc motor.

It should be noted that the above steps S101 to S102 may be executed multiple times, and each time of execution may correspond to one cycle. In the multiple execution processes, if the lubrication flow interval corresponding to the expected lubrication flow is changed, the lubricating oil pump can be continuously controlled to work according to the target lubrication flow corresponding to the changed lubrication flow interval. For example, if steps S101-S102 were executed last time, the determined lubrication flow rate interval is (Q)₂，Q₃]When the steps S101-S102 are executed this time, the determined lubrication flow rate interval is (Q)₃，Q₄]Then the target lubrication flow rate for controlling the operation of the lubrication oil pump can be set from (Q)₂，Q₃]Corresponding target lubrication flow is switched to (Q)₃，Q₄]The corresponding target lubrication flow rate.

Compared with the prior artIf the total range of the desired lubrication flow is (0, Q)_M]The rotational speed of the lubricant pump is equal to (0, Q)_M]Corresponding full speed range. In this embodiment, the lubrication flow interval corresponding to the expected lubrication flow is determined from the at least two lubrication flow intervals, so that the operation of the lubrication pump is controlled according to the target lubrication flow corresponding to the determined lubrication flow interval, that is, a segmented lubrication strategy is adopted, and the rotation speed of the lubrication pump is changed from the full rotation speed range to the specific rotation speed corresponding to the at least two target lubrication flow intervals, thereby reducing or avoiding the NVH problem caused by resonance when the lubrication pump operates in the full rotation speed range.

On the basis of the foregoing embodiments, the present application also provides another lubrication control method of a wet clutch. Specific implementations of the method are described and illustrated below with reference to the examples and the figures.

Second embodiment

Referring to fig. 2, a flowchart of another lubrication control method for a wet clutch according to an embodiment of the present application is shown.

As shown in fig. 2, the method for controlling lubrication of a wet clutch according to the present embodiment includes:

step S201: at least two lubrication flow intervals are divided in advance, and target lubrication flows corresponding to the at least two lubrication flow intervals are determined.

In an alternative implementation, the rotation speed range of the lubrication oil pump corresponding to the target lubrication flow rate does not overlap with the rotation speed range when resonance occurs due to rotation of the lubrication oil pump. Because two rotational speed ranges are not overlapped, the lubricating oil pump can avoid the rotational speed range which generates resonance due to rotation as far as possible when in work, thereby avoiding the resonance condition as far as possible and avoiding the NVH problem caused by resonance.

Specifically, since the rotation speed of the lubricating oil pump is positively correlated with the flow rate of the lubricating oil supplied by the lubricating oil pump, the rotation speed of the lubricating oil pump can be directly and indirectly represented through the lubricating flow rate, that is, the rotation speed range when resonance occurs can be indirectly determined by determining the flow rate of the lubricating oil supplied by the lubricating oil pump when resonance occurs due to the rotation of the lubricating oil pump. A person skilled in the art may also characterize the rotation speed range of the lubrication oil pump by using other parameters, as long as it is ensured that the rotation speed range of the lubrication oil pump corresponding to the target lubrication flow rate does not overlap with the rotation speed range when resonance is generated due to the rotation of the lubrication oil pump, which is not limited in this embodiment.

In another optional implementation manner, the at least two lubrication flow intervals and the corresponding target flow intervals are determined according to NVH experiment results of the lubricating oil pump. Therefore, when the lubricating oil pump is controlled to work according to the target flow interval corresponding to the lubricating flow interval, the NVH problem can be avoided as much as possible.

NVH refers to Noise, Vibration, and Harshness, and they are frequently studied together because they occur simultaneously and are inseparable in mechanical Vibration of a vehicle. Statistics show that there is about 1/3 failure problem in the vehicle and NVH problem of the vehicle.

The NVH experiment of lubricating oil pump means the experiment of verifying the NVH problem that leads to owing to the lubricating oil pump, and in actual use, the NVH problem of vehicle can have multiple reason to lead to, only relates to the NVH problem that leads to owing to the lubricating oil pump in this application, to other reasons that cause the NVH problem, this application is no longer repeated here.

Through the experimental result of the NVH, the flow rate of the lubricating oil provided by the lubricating oil pump when the NVH problem is caused, namely the lubricating flow rate corresponding to the experimental result of the NVH can be determined. And furthermore, when the target lubrication flow corresponding to the lubrication flow interval is determined, the lubrication flow corresponding to the NVH experiment result can be avoided, so that when the lubricating oil pump is controlled to work according to the target lubrication flow, the lubrication flow corresponding to the NVH problem can be avoided.

During specific implementation, at least two lubrication flow intervals can be determined, then a value serving as a target lubrication flow is selected from each lubrication flow interval according to an NVH (noise vibration and harshness) experiment result, and the target lubrication flow is not overlapped with the value of the lubrication flow corresponding to the NVH experiment result; or, the value of a fixed position in each lubrication flow interval may be determined as the corresponding target lubrication flow, and then the lubrication flow interval is divided according to the NVH experiment result, and it is ensured that the target lubrication flow in each lubrication flow interval does not overlap with the value of the lubrication flow corresponding to the NVH experiment result.

In this embodiment, each lubrication flow interval may correspond to only one target lubrication flow, or to multiple target lubrication flows; the number of the target lubrication flow rates corresponding to different lubrication flow rate intervals may be the same or different, and this embodiment does not limit this.

Further, the target lubrication flow rate corresponding to the lubrication flow rate interval includes: and the upper limit value of the lubricating flow interval.

Specifically, if it is determined that the target lubrication flow is the upper limit value of the lubrication flow interval, the partition limit may be determined according to the NVH experiment result, and it is ensured that the partition limit is not overlapped with the value of the lubrication flow corresponding to the NVH experiment result, so that at least two lubrication flow intervals are obtained by partition according to the partition limit, and it is ensured that the upper limit of the lubrication flow interval is not overlapped with the value of the lubrication flow corresponding to the NVH experiment result.

In addition, when the lubrication flow rate interval is divided, other factors need to be considered, for example, the difference between the target lubrication flow rate and the expected lubrication flow rate needs to be considered to be smaller than a preset value, so that the actual corresponding lubrication flow rate of the wet clutch is smaller than the expected lubrication flow rate.

In actual use, if the expected lubrication flow rate is greatly different from the target lubrication flow rate, the lubrication flow rate may be insufficient or high. If the lubricating flow is insufficient, the surface temperature of the wet clutch can be rapidly increased, and the service life of the wet clutch can be shortened; if the lubricating flow is high, the lubricating oil pump can work continuously, the belt-driving Torque (Drag Torque) of the wet clutch is large, the control difficulty of the wet clutch is increased, and the gear-releasing action of the shifting fork can be influenced. Therefore, it is necessary to ensure that the difference between the target lubrication flow rate and the desired lubrication flow rate is smaller than a preset value. In specific implementation, the difference between the upper limit and the lower limit of the lubrication flow interval can be ensured to be smaller than a preset value, so as to indirectly ensure that the difference between the target lubrication flow and the expected lubrication flow is smaller than the preset value.

Step S202: and judging whether the wet clutch is in a friction state or not. If yes, go to step S203; if not, go to step S206.

The engagement process of the wet clutch may include three stages, a squeeze stage, a compression stage, and a full-asperity contact stage. In the whole engaging process of the wet clutch, the rotating speeds of the main part and the auxiliary part are not equal, so that the main part and the auxiliary part generate slipping, and the friction torque, the rotating speed and the slipping power of the clutch change along with the change of time in the slipping process.

Whether the wet clutch is in the engagement process can be determined by judging whether the wet clutch is in the friction state, and whether lubricating oil is supplied to the wet clutch can be further determined.

For a specific manner of determining whether the wet clutch is in the slipping state, reference may be made to related technologies, and details of this embodiment are not repeated herein.

Step S203: determining the desired lubrication flow based on a slip power of the wet clutch.

After step S203 is executed, step S204 is continuously executed.

Specifically, the method for determining the sliding friction power and the method for determining the expected lubrication flow according to the sliding friction power refer to related technologies, and the description of this embodiment is omitted here.

In an implementation manner, step S203 may specifically include: and determining the expected lubricating flow according to the sliding friction power of the wet clutch and the lubricating oil temperature of the wet clutch.

The temperature of the lubricating oil of the wet clutch may specifically be the temperature of the lubricating oil of the friction surface of the wet clutch. Since the temperature of the friction surface cannot be determined by the sensor, the temperature of the lubricating oil before it enters the friction surface can be used here to characterize the lubricating oil temperature.

Of course, during specific implementation, the expected lubrication flow rate may also be determined according to other factors, which is not limited in this embodiment, and the specific manner of calculating the expected lubrication flow rate is not described herein again.

Step S204: and determining a lubrication flow interval corresponding to the expected lubrication flow of the wet clutch.

After step S204 is executed, step S205 is continuously executed.

The method comprises the steps of determining a lubrication flow interval corresponding to a desired lubrication flow of the wet clutch, namely determining a lubrication flow interval to which a value of the desired lubrication flow belongs from at least two lubrication intervals. For details, reference may be made to step S101 in the first embodiment.

Step S205: and controlling the lubricating oil pump to work according to the determined target lubricating flow corresponding to the lubricating flow interval.

After step S205 is executed, the execution of the method steps may be ended, or the process may return to step S202 and be executed again.

One lubricating flow interval can correspond to one or more target lubricating flows, and when one target lubricating flow corresponds to one target lubricating flow, the lubricating oil pump can be controlled to work directly according to the target lubricating flow; when a plurality of target lubrication flow rates correspond, the operation of the lubricating oil pump may be controlled according to one target lubrication flow rate closest to the desired lubrication flow rate.

In one implementation, step S205 includes: and determining the control lubrication flow output by the controller in the current period according to the final control lubrication flow output by the controller in the last period and the current target lubrication flow, so as to control the lubricating oil pump to work through the control lubrication flow.

The control lubrication flow output in the current period is determined according to the final control lubrication flow output in the previous period and the current target lubrication flow, so that the control lubrication flow in the current period can be output on the basis of the final control lubrication flow in the previous period, and sudden output change is prevented.

Specifically, determining the control lubrication flow output by the controller in the current period according to the final control lubrication flow output by the controller in the last period and the current target lubrication flow may include the following three cases:

a) and if the current target lubrication flow is larger than the final control lubrication flow of the previous period, determining that the control lubrication flow output by the controller in the current period is equal to the current target lubrication flow. At this time, the control lubrication flow rate output in the current period is increased from the final control lubrication flow rate of the previous period to the current target lubrication flow rate.

b) And if the current target lubrication flow is smaller than the final control lubrication flow of the previous period, determining that the control lubrication flow output by the controller in the current period is gradually reduced from the final control lubrication flow of the previous period to the current target lubrication flow. At this time, the initial value of the control lubrication flow output in the current period is equal to the final control lubrication flow in the previous period, and the control lubrication flow is slowly reduced to the current target lubrication flow.

c) And if the current target lubrication flow is equal to the final control lubrication flow of the previous period, determining that the control lubrication flow output by the controller in the current period is equal to the final control lubrication flow of the previous period. At this time, the control lubrication flow output in the current period is equal to the final control lubrication flow in the previous period.

The control lubrication flow output in the current period is determined by comparing the current target lubrication flow with the final control lubrication flow value in the previous period and adopting one of the three schemes according to the comparison result, so that the output control lubrication flow value is prevented from suddenly dropping.

Step S206: and controlling the lubricating oil pump to work according to the lubricating oil leakage rate.

When the wet clutch is not in the slip state, the present step S206 is executed. Step S206 may be continuously executed, and the determination is made by step S202 in the process of execution until the execution of step S206 is stopped when it is determined by step S202 that the wet clutch is in the slip state. Alternatively, the execution of step S206 may be directly ended.

The lubricating oil pump is controlled to work according to the leakage rate of the lubricating oil, so that the lubricating oil channel of the wet clutch can be in a full state, and therefore sufficient lubricating flow can be provided for the wet clutch from the lubricating oil channel when the wet clutch is just switched from the non-slipping state to the slipping state.

On the basis of the foregoing embodiments, the present application also provides another lubrication control method of a wet clutch. Specific implementations of the method are described and illustrated below with reference to the examples and the figures.

Third embodiment

In this embodiment, a lubrication control method of a wet clutch will be specifically described in a specific usage scenario. Referring to fig. 3, a flowchart of another lubrication control method for a wet clutch according to an embodiment of the present application is shown.

As shown in fig. 3, the method for controlling lubrication of a wet clutch according to the present embodiment includes:

step S301: a plurality of lubrication flow rate intervals are predetermined, and the upper limit of the lubrication flow rate interval is set to a target lubrication flow rate corresponding to the upper limit.

The divided lubrication flow interval may be:

interval of flow

(0，Q1]

(Q1，Q2]

(Q2，Q3]

(Q3，Q4]

……

(QM-1，QM]

And the upper limit value of the lubricating flow interval is determined according to the NVH experiment result of the lubricating oil pump, and the resonance frequency is avoided.

Step S302: and judging whether the wet clutch is in a friction state or not.

If yes, go to step S303; if not, go to step S309.

Step S303: and determining the expected lubricating power q (n) of the wet clutch in the current period according to the slip power of the wet clutch and the lubricating oil temperature acquired in the current period.

Specifically, after the sliding friction power and the lubricating oil temperature are obtained through sampling, the expected lubricating flow q (n) of the wet clutch can be determined by searching a lubricating and cooling table, and the lubricating and cooling table is established in advance according to the working condition of the wet clutch.

Step S304: determining the section of the expected lubricating flow Q (n) corresponding to the lubricating flow as (Q)₂，Q₃]。

Step S305: judging the upper limit Q of the lubrication flow interval₃And the value of the final lubrication control flow Q' (n-1) output by the transmission controller TCU in the previous period.

If Q₃>Q' (n-1), then step S306 is executed; if Q₃<Q' (n-1), then step S307 is executed; if Q₃Q' (n-1), step S308 is executed.

Step S306: controlling the lubricating flow Q' (n) ═ Q outputted by the TCU in the current period₃。

Step S307: the control lubrication flow Q '(n) output by the control gearbox controller TCU in the current period is slowly reduced from Q' (n-1) to Q₃。

Slowly decreases from Q' (n-1) to Q₃Multiple drops may be made, and the value of each drop may be Δ Q.

The multiple control lubrication flows output by the gearbox controller TCU during descent also avoid the resonant frequency.

Step S308:controlling the lubricating flow Q' (n) ═ Q outputted by the TCU in the current period₃(also Q' (n-1), the two are equal).

In the above steps S305 to S308, the control lubrication flow output by the transmission controller TCU in the current period is used to control the operation of the lubrication oil pump.

Step S309: and determining the control lubrication flow output by the TCU according to the lubrication oil leakage rate. To control the operation of the lubricant pump via a transmission controller.

The leakage rate of the lubricating oil can correspond to the oil temperature of the lubricating oil, and the lower the oil temperature is, the higher the viscosity of the lubricating oil is, and the smaller the leakage rate of the lubricating oil is.

Specifically, as shown in fig. 4, the lubricating oil pump includes a Brushless Direct Current Motor (BLDC) and a mechanical pump (pump) connected to the Brushless dc Motor (coupling). And the transmission controller TCU inputs an electric signal corresponding to the control lubrication flow into the brushless direct current motor, so that the brushless direct current motor works at a rotating speed corresponding to the control lubrication flow. The brushless direct current motor supplies power to the mechanical pump, lubricating oil is pumped by the mechanical pump, and the flow of the pumped lubricating oil corresponds to the rotating speed of the brushless direct current motor.

In this embodiment, a lubrication flow interval of an expected lubrication flow is determined from at least two lubrication flow intervals, and the operation of the lubrication oil pump is controlled according to a target lubrication flow corresponding to the lubrication flow interval, that is, a segmented lubrication strategy is adopted, so that the rotation speed range of the lubrication oil pump is changed from a full rotation speed range to a specific rotation speed corresponding to at least two target lubrication flows, and thus resonance caused by the proximity of the noise frequency of the CCEOP of the lubrication oil pump and the mechanical natural frequency of the housing between the housings connected to the noise pump (coupling) can be avoided as much as possible, resonance caused by the proximity of the torque pulsation frequency of the brushless dc motor of the lubrication oil pump and the mechanical natural frequency of the stator or rotor of the brushless dc motor can be avoided as much as possible, and further, the NVH problem caused by the resonance when the lubrication oil pump operates in the full rotation speed range is reduced or avoided.

Based on the lubrication control method of the wet clutch provided by the foregoing embodiment, correspondingly, the present application further provides a lubrication control device of the wet clutch. The following describes a specific implementation of the system with reference to the drawings and embodiments.

Fourth embodiment

Referring to fig. 5, the drawing is a schematic structural diagram of a lubrication control device of a wet clutch according to an embodiment of the present application.

As shown in fig. 5, the lubrication control device for a wet clutch according to the present embodiment includes: an interval determination module 501 and an interval control module 502.

An interval determining module 501, configured to determine a lubrication flow interval corresponding to an expected lubrication flow of a wet clutch, where the number of the lubrication flow intervals includes at least two, and the at least two lubrication flow intervals correspond to target lubrication flows respectively;

and the interval control module 502 is configured to control the operation of the lubricating oil pump according to the determined target lubricating flow corresponding to the lubricating flow interval, so that the rotating speed of the lubricating oil pump corresponds to the target lubricating flow.

The lubrication control device of the wet clutch provided in the embodiment of the present application, through the lubrication control device of the wet clutch, may determine the lubrication flow interval corresponding to the expected lubrication flow from at least two lubrication flow intervals, so as to control the operation of the lubrication oil pump according to the target lubrication flow corresponding to the determined lubrication flow interval, that is, a segmented lubrication strategy is adopted, the rotation speed of the lubrication oil pump is changed from a full rotation speed range to a specific rotation speed corresponding to at least two target lubrication flows, and further, the NVH problem caused by resonance when the lubrication oil pump operates in the full rotation speed range is reduced or avoided.

Optionally, in any embodiment of the present application, the at least two lubrication flow intervals and the target flow interval corresponding to the at least two lubrication flow intervals are determined according to NVH experimental results of the lubrication oil pump.

Optionally, in any embodiment of the present application, a rotation speed range of the lubrication oil pump corresponding to the target lubrication flow rate does not overlap with a rotation speed range when resonance is generated due to rotation of the lubrication oil pump.

Optionally, in any embodiment of the present application, the apparatus further includes: and the expected flow determining module is used for determining the expected lubricating flow according to the friction power of the wet clutch if the wet clutch is in the friction state.

Optionally, in any embodiment of the present application, the apparatus further includes: and the speed control module is used for controlling the lubricating oil pump to work according to the lubricating oil leakage speed if the wet clutch is not in the friction sliding state.

Optionally, in any embodiment of the present application, the expected flow rate determining module is specifically configured to: and determining the expected lubricating flow according to the sliding friction power of the wet clutch and the lubricating oil temperature of the wet clutch.

Optionally, in any embodiment of the present application, the target lubrication flow corresponding to the lubrication flow interval includes: and the upper limit value of the lubricating flow interval.

Optionally, in any embodiment of the present application, the interval control module 502 includes: and the period control module is used for determining the control lubrication flow output by the controller in the current period according to the final control lubrication flow output by the controller in the last period and the current target lubrication flow, so as to control the lubricating oil pump to work through the control lubrication flow.

Optionally, in any embodiment of the present application, the period control module is specifically configured to:

if the current target lubrication flow is larger than the final control lubrication flow of the previous period, determining that the control lubrication flow output by the controller in the current period is equal to the current target lubrication flow;

or if the current target lubrication flow is smaller than the final control lubrication flow of the previous period, determining that the control lubrication flow output by the controller in the current period is gradually reduced from the final control lubrication flow of the previous period to the current target lubrication flow;

or, if the current target lubrication flow is equal to the final control lubrication flow of the previous period, determining that the control lubrication flow output by the controller in the current period is equal to the final control lubrication flow of the previous period.

Based on the lubrication control method of the wet clutch provided in the foregoing embodiment, accordingly, the present application also provides a vehicle including a controller for executing the lubrication control method of the wet clutch in the foregoing embodiment. Therefore, NVH problems caused by resonance when a lubricating oil pump of a vehicle works in a full rotating speed range are reduced or avoided.

It should be noted that, in the present specification, all the embodiments are described in a progressive manner, and the same and similar parts among the embodiments may be referred to each other, and each embodiment focuses on the differences from the other embodiments. In particular, for the apparatus and system embodiments, since they are substantially similar to the method embodiments, they are described in a relatively simple manner, and reference may be made to some of the descriptions of the method embodiments for related points. The above-described embodiments of the apparatus and system are merely illustrative, and the units described as separate parts may or may not be physically separate, and the parts suggested as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. 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 one specific embodiment of the present application, but the scope of the present application is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present application should be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.