CN113653797B

CN113653797B - Upshift control method

Info

Publication number: CN113653797B
Application number: CN202110776296.6A
Authority: CN
Inventors: 苏宇; 林霄喆; 孙艳; 谭艳军; 付军; 张旭; 王二朋; 王开文; 张恒; 孙剑斌; 李江; 赵欣; 王瑞平
Original assignee: Yiwu Geely Automatic Transmission Co ltd; Zhejiang Geely Holding Group Co Ltd; Ningbo Geely Royal Engine Components Co Ltd; Zhejiang Geely Power Train Co Ltd
Current assignee: Yiwu Geely Automatic Transmission Co ltd; Zhejiang Geely Holding Group Co Ltd; Ningbo Geely Royal Engine Components Co Ltd; Zhejiang Geely Power Train Co Ltd
Priority date: 2021-07-08
Filing date: 2021-07-08
Publication date: 2022-11-29
Anticipated expiration: 2041-07-08
Also published as: WO2023279634A1; CN113653797A

Abstract

The invention provides a gear-up control method, which comprises the following steps: in the pre-charging stage, when the first brake and the second brake meet the preset condition, the torque of the engine is reduced to the preset torque, and the pressure of the clutch C0 is adjusted according to the torque requirement of the engine. And in the torque stage, the second brake is adjusted to the first torque, the first brake is adjusted to the second torque, and the torque of the driving motor works along the external characteristic. And in the rotating speed stage, the rotating speed of the input shaft is changed to the rotating speed of a target gear, the torque of the first brake is increased, the torque of the driving motor is increased, and the generator outputs reverse torque. In the closing stage, the rotation speeds of the engine and the input shaft of the driving motor are synchronous, the torque of the second brake is reduced to zero, the torque of the first brake is added with safe torque, the torque of the generator is zero, the torque of the engine is controlled by external characteristic torque according to the current rotation speed, and the clutch C0 is locked according to the torque of the engine. The invention reduces the risk of Double Mass Flywheels (DMF) parallel connection and also reduces the reverse torque of the P1 spline shaft.

Description

Upshift control method

Technical Field

The invention relates to the technical field of hybrid power, in particular to a gear-up control method.

Background

The transmission has evolved through manual transmissions, automatic transmissions, automated manual transmissions, dual clutch transmissions, and current hybrid transmissions. One key technology in transmissions is shift control, and as transmissions have evolved, the methods of shifting the transmissions have been updated.

The phenomenon that an engine and a motor are just connected or an indirect rigid connection shaft exists in the current market, and meanwhile, the problem of over-doubling and circling also exists in the engine with a dual-mass flywheel, so that the phenomenon is easy to occur. AT shift control strategies and DCT shift strategies are more available on the market for automatic transmissions, hybrid transmissions and the like, but neither of these methods takes the structural characteristics of the hybrid transmission into good consideration.

For example, when the high-torque power is shifted up, the engine generates high torque, the P3 motor generates high torque in a reverse direction, the P1 spline shaft is subjected to great reverse torque impact in the rotation speed stage of shifting, and at the moment, the dual-mass flywheel has great risk of combining rings. The method for reducing the torque of the engine by 0 is used for gear shifting, is not beneficial to engine combustion, and is easy to initiate pre-ignition.

Therefore, an upshift control method is needed to solve the above problems.

Disclosure of Invention

The invention aims to provide a gear-up control method, which can ensure smooth gear shifting and dynamic property, reduce the risk of double-mass flywheel (DMF) parallel ring and reduce the reverse torque of a P1 spline shaft.

The technical problem to be solved by the invention is realized by adopting the following technical scheme:

an upshift control method comprising the steps of: s1: in the pre-charging stage, when the first brake and the second brake meet a preset condition, the torque of the engine is reduced to a preset torque, and the pressure of the clutch C0 is adjusted according to the torque demand of the engine; s2: in the torque stage, the second brake is reduced to a first torque, the first brake is increased to a second torque, and the torque of the driving motor is changed according to a preset strategy; s3: in the rotating speed stage, the rotating speed of the input shaft is reduced to the rotating speed of a target gear, the torque of the first brake is increased, the torque of the driving motor is increased, and the generator outputs reverse torque; s4: in the closing stage, the rotation speed of the engine and the input shaft of the driving motor is synchronous, the torque of the second brake is reduced to zero, the torque of the first brake is added with safe torque, the torque of the generator is adjusted to zero, the torque of the engine is controlled according to the current rotation speed through external characteristic torque control, and the clutch C0 is locked according to the torque of the engine.

In a preferred embodiment of the present invention, the step S3 includes: and when detecting that the double-mass flywheel is about to have the over-limit torque, triggering a clutch C0 slip mechanism, and performing slip control through the clutch C0.

In a preferred embodiment of the present invention, the preset conditions include: the first brake performs pre-charging action to adjust torque to the first torque, and the second brake reduces torque to the second torque.

In a preferred embodiment of the present invention, the predetermined strategy is an external characteristic torque.

In a preferred embodiment of the present invention, the step S1 includes: and when the accelerator opening is larger than a set accelerator opening threshold value and the power downshift cannot be triggered under the current gear, judging to trigger the power upshift control, and otherwise, continuously judging whether to trigger the power upshift control.

In a preferred embodiment of the present invention, the step S2 includes: the generator torque is zero and the engine maintains the preset torque.

In a preferred embodiment of the present invention, the step S3 further includes: the second brake holds the first torque, and the engine holds the preset torque.

The technical effect achieved by adopting the technical scheme is as follows: for the rotating speed stage of the gear shifting process, the torque of the first brake can be increased under the condition of allowing the use capacity to assist gear shifting, and the load capacity of the P1 spline shaft can be reduced. The shift begins to reduce the engine to the appropriate torque. The slip capability of clutch C0 is used to protect the dual mass flywheel and the P1 module spline shaft. The risk of double-mass flywheel (DMF) doubling is reduced while ensuring smooth and smooth gear shifting and dynamic property, and the reverse torque of the P1 spline shaft is also reduced.

The foregoing description is only an overview of the technical solutions of the present invention, and in order to make the technical means of the present invention more clearly understood, the present invention may be implemented in accordance with the content of the description, and in order to make the above and other objects, features, and advantages of the present invention more clearly understood, the following preferred embodiments are specifically illustrated in the accompanying drawings and described in detail.

Drawings

FIG. 1 is a flow chart illustrating an upshift control method according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a 3DHT according to an embodiment of the present invention;

fig. 3 is a schematic diagram illustrating an operation of the present invention.

Detailed Description

To further illustrate the technical measures and effects taken by the present invention to achieve the intended objects, embodiments of the present invention will be described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below are only a part of the embodiments of the present invention, and not all of them. All other embodiments, which can be obtained by a person skilled in the art based on the embodiments of the present invention without any creative effort, belong to the protection scope of the embodiments of the present invention. While the present invention has been described in connection with the preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but is intended to cover various modifications, equivalent arrangements, and specific embodiments thereof.

Referring to fig. 1 to 3, fig. 1 is a flowchart illustrating an upshift control method according to an embodiment of the present invention.

As shown in fig. 1, the upshift control method of the present invention includes the steps of:

s1: in the pre-charging stage, when the first brake and the second brake meet the preset condition, the torque of the engine is reduced to the preset torque, and the pressure of the clutch C0 is adjusted according to the torque demand of the engine.

S2: and in the torque phase, the second brake is reduced to a first torque, the first brake is increased to a second torque, and the torque of the driving motor is changed according to a preset strategy.

S3: in the rotating speed stage, the rotating speed of the input shaft is reduced to the rotating speed of a target gear, the torque of the first brake is increased, the torque of the driving motor is increased, and the generator outputs reverse torque.

S4: in the closing stage, the rotation speed of the engine and the input shaft of the driving motor is synchronous, the torque of the second brake is reduced to zero, the torque of the first brake is added with safe torque, the torque of the generator is adjusted to zero, the torque of the engine is controlled according to the current rotation speed through external characteristic torque control, and the clutch C0 is locked according to the torque of the engine.

The step S3 comprises the following steps: and when detecting that the double-mass flywheel is about to have the over-limit torque, triggering a clutch C0 slip mechanism, and performing slip control through the clutch C0.

The preset conditions include: the first brake performs pre-charging action to adjust torque to the first torque, and the second brake reduces torque to the second torque.

Specifically, the first torque is a clutch half-engagement point torque. And the oil charging control is characterized in that the clutch pressure corresponding to the half-joint point of the clutch is used as the target oil charging pressure, the current pressure of the clutch is used as the actual pressure, and calibration optimization is carried out according to the oil temperatures of different gearboxes, the target oil charging pressure of the clutch and the actual pressure difference.

Wherein the second torque is a slip torque, and the reduction of the second brake torque to the slip torque point can be understood as the torque at which the second brake is balanced with the system torque.

The preset strategy is an external characteristic torque strategy.

The external characteristic and a part of the characteristic of the engine are collectively referred to as the speed characteristic of the engine, and the external characteristic curve of the engine is a curve in which the output power (torque) of the engine measured when the opening degree of the throttle valve of the engine is 100% varies with the rotation speed.

Step S1 comprises, before: and when the accelerator opening is larger than a set accelerator opening threshold value and power downshifting cannot be triggered under the current gear, judging to trigger power upshifting control, and otherwise, continuously judging whether to trigger power upshifting control.

The step S2 comprises the following steps: the generator torque is zero and the engine maintains the preset torque.

Step S3 further includes: the second brake holds the first torque, and the engine holds the preset torque.

The present invention is described in detail below with reference to fig. 1 to 3:

referring to fig. 2 and 3, the power up-shift of the hybrid transmission according to the present invention is divided into four stages, namely, a pre-charge stage, a torque stage, a rotation speed stage, and a close stage.

In the pre-charging stage, the first Brake (inggoing Brake, brake-2) performs pre-charging action to enable the clutch to reach a half-joint point (kiss point), and the second Brake (offgoing Brake, brake-1) reduces the torque to a slip torque boundary. At this point, the engine begins torque reduction control and Clutch C0 (Clutch-0) will adjust the pressure according to the engine torque request. Where the shift begins to reduce the engine to the desired torque, rather than 0 torque. The torque reduction can be done economically while preventing pre-ignition.

During the torque phase, the input shaft remains unchanged, the offgoing Brake starts to reduce the torque to the half-engagement point (kiss point), and the first Brake (inging Brake, brake-2) starts to increase the torque to its slip torque point. The drive motor torque is operated along the external characteristic, the generator maintains 0 torque, the engine continues to maintain a low torque demand, and the clutch C0 regulates pressure based on the engine torque demand.

In the rotating speed stage, the rotating speed of an input shaft is required to be reduced to a target gear rotating speed, an offgoing Brake keeps a half-joint point (kiss point), a first Brake (one Brake, brake-2) actively increases torque under the condition that the capacity of the Brake allows, the auxiliary rotating speed stage is completed, the reduction amplitude of the input torque is relieved, the torque of a driving motor begins to increase along with the reduction of the rotating speed at the moment, a generator reversely outputs the torque for the reverse acceleration of the reduction of the rotating speed of an input shaft, and an engine continues to keep low torque output, if the system detects that the over-limit torque of a dual-mass flywheel is about to occur, a clutch C0 slipping mechanism is immediately triggered to promote the driving motor and the engine to generate certain slip, and at the moment, the slip control in the process is realized by C0. The engine, the driving motor and the generator are coaxial in a parallel mode, and the scheme describes parallel mode gear shifting. Thus, the rotational speed is common. The torque of the crank 2 is increased under the condition of allowing the use capacity to assist the gear shifting, so that the gear shifting smoothness can be ensured, and the load capacity of the P1 spline shaft can be reduced. The dual mass flywheel and spline shaft can then be protected by reasonable use of the slip capability of clutch C0.

Clutch C0 regulates the pressure out, and when Tclu < TEng (clutch engagement torque less than engine torque will slip, this part controls C0 torque closed loop to control the corresponding speed difference) (TEng = Tclu + J α).

In the closing stage, the rotation speeds of the engine and the input shaft of the driving motor are synchronous, the torque of the offgoing Brake is reduced to 0, the torque of the first Brake (trip-2) is added with the safe torque, namely, the safe torque is simply the reasonable torque (standard torque), the driving motor keeps continuously outputting the output, the torque of the generator is 0, the torque of the engine outputs the external characteristic torque according to the current rotation speed, and the clutch C0 locks according to the torque of the engine.

In the above embodiment, the torque of the first Brake (Brake-2), the torque of the driving motor, the torque of the generator, the torque of the engine, and the torque of the clutch C0 may be appropriately varied according to actual conditions to combine better control. The execution timing of the torque of the first Brake (Brake-2), the torque of the driving motor, the torque of the generator, the torque of the engine and the torque of the clutch C0 can be flexibly controlled to start and end. The torque control gradient can be optimized according to actual conditions.

The upshift control strategy described in the present invention may also be modified to a power downshift shift process control strategy.

The gear-up control method provided by the invention reduces the torque of the engine to a proper torque when the gear shifting is started, and finishes the torque reduction on the premise of preventing the occurrence of pre-ignition. For the rotating speed stage in the gear shifting process, the torque of the Brake2 is increased under the condition of allowing the use capacity to assist in gear shifting, so that the gear shifting smoothness can be ensured, and the load capacity of the P1 spline shaft can be reduced. The slipping capacity of the clutch C0 is used for effectively protecting the dual-mass flywheel and the P1 module spline shaft, and the dual-mass flywheel parallel ring and the spline shaft are prevented from being broken. The introduction of a plurality of torque control units is used for controlling gear shifting, and the operability and the flexibility are higher.

It should be understood that, although the steps in the flowchart of fig. 1 are shown in order as indicated by the arrows, the steps are not necessarily performed in order as indicated by the arrows. The steps are not performed in the exact order shown and may be performed in other orders unless explicitly stated herein. Moreover, at least some of the steps in fig. 1 may include multiple sub-steps or multiple stages that are not necessarily performed at the same time, but may be performed at different times, in different orders, and may be performed alternately or alternately with other steps or at least some of the sub-steps or stages of other steps.

Through the above description of the embodiments, those skilled in the art will clearly understand that the embodiments of the present invention may be implemented by hardware, or by software plus a necessary general hardware platform. Based on such understanding, the technical solutions of the embodiments of the present invention may be embodied in the form of a software product, which may be stored in a non-volatile storage medium (which may be a CD-ROM, a usb disk, a removable hard disk, etc.), and includes several instructions for enabling a computer device (which may be a personal computer, a server, or a network device, etc.) to execute the methods described in the various implementation scenarios of the embodiments of the present invention.

The present invention is not limited to the details of the above embodiments, which are exemplary, and the modules or processes in the drawings are not necessarily essential to the implementation of the embodiments of the present invention, and should not be construed as limiting the present invention.

Claims

1. An upshift control method, characterized by comprising the steps of:

s1: in the pre-charging stage, when the first brake and the second brake meet the preset condition, the torque of the engine is reduced to the preset torque, and the pressure of the clutch C0 is adjusted according to the torque requirement of the engine;

s2: in the torque stage, the second brake is reduced to a first torque, the first brake is increased to a second torque, and the torque of the driving motor is changed according to a preset strategy;

s3: in the rotating speed stage, the rotating speed of the input shaft is reduced to the rotating speed of a target gear, the torque of the first brake is increased, the torque of the driving motor is increased, and the generator outputs reverse torque;

2. The upshift control method according to claim 1, wherein step S3 includes: and when detecting that the double-mass flywheel is about to have the over-limit torque, triggering a clutch C0 slip mechanism, and performing slip control through the clutch C0.

3. The upshift control method according to claim 1, wherein said preset conditions include: the first brake performs pre-charging action to adjust torque to the first torque, and the second brake reduces torque to the second torque.

4. The upshift control method of claim 1, wherein said preset strategy is an external characteristic torque.

5. The upshift control method according to claim 1, wherein step S1 is preceded by: and when the accelerator opening is larger than a set accelerator opening threshold value and power downshifting cannot be triggered under the current gear, judging to trigger power upshifting control, and otherwise, continuously judging whether to trigger the power upshifting control.

6. The upshift control method according to claim 1, wherein step S2 includes: the generator torque is zero and the engine maintains the preset torque.

7. The upshift control method according to claim 1, wherein step S3 further includes: the second brake holds the first torque, and the engine holds the preset torque.