A method for correcting target gear of a dual clutch transmission

Abstract

The application discloses a target gear correction method of a double-clutch transmission, mainly comprising the following steps: S1, in a process of vehicle stable-speed driving, identifying a hard pressing and hard releasing large throttle condition, and recording a cumulative number; S2, target gear correction condition judgment; and S3, target gear correction. Through the correction of the target gear, the application effectively solves the engine air blowing problem under the hard pressing and hard releasing condition and the vehicle shaking problem caused by the change of the intention of gear shifting.

Description

Technical Field

[0001] This invention relates to the field of dual-clutch transmissions, and more specifically to a method for correcting the target gear position in a dual-clutch transmission. Background Technology

[0002] Among all performance evaluation indicators for dual-clutch transmissions, engine speed NVH and overall vehicle driving smoothness are extremely important; and among all performance evaluation conditions, extreme conditions are also one of the important evaluation conditions. Excellent performance under extreme conditions better reflects the stability and reliability of the transmission assembly, and also better reflects the robustness and accuracy of software control.

[0003] When the accelerator is pressed hard, a downshift will be triggered when the throttle opening is sufficient for downshifting; when the accelerator is released quickly, an upshift will be triggered. Continuous hard pressing and releasing of the accelerator will frequently trigger upshifts and downshifts, resulting in high engine speeds but no significant increase in power, and noticeable jerking throughout the vehicle.

[0004] Therefore, under certain conditions, optimizing the engine speed NVH issues and overall vehicle smoothness caused by frequent gear shifts when rapidly pressing and releasing the accelerator is a current challenge. Summary of the Invention

[0005] This invention provides a method for correcting the target gear position of a dual-clutch transmission. By correcting the target gear position, this invention effectively solves the problems of engine dry blowing under rapid pressing and releasing conditions and vehicle vibration caused by changing the intended gear shift.

[0006] The technical solutions to the above technical problems are as follows:

[0007] A method for correcting the target gear of a dual-clutch transmission includes the following steps:

[0008] S1, during the process of driving at a stable speed, identify the situation of sudden pressing and releasing of the accelerator, record and count the cumulative number of times;

[0009] S2, Target gear adjustment condition judgment: The cumulative counter count is ≥ N times, where N is determined based on different customer needs;

[0010] S3, Target Gear Correction: Under the condition of rapid acceleration, the target downshift gear correction method is target gear + A, where A ≤ (current gear - target gear), and the value of A is determined based on customer requirements.

[0011] Furthermore, in step S1, when all of the following conditions are met, the system is identified as experiencing a sudden acceleration and deceleration of the accelerator pedal, and the cumulative counter is incremented by 1:

[0012] 1-1) Throttle opening condition: Throttle opening ≥ 100° when accelerator is depressed ,in This is the minimum throttle opening that triggers a downshift at this stable vehicle speed. It can be found in the shift map. The throttle opening should be [value missing] when releasing the throttle. Reduced to 0%;

[0013] 1-2) |Throttle opening change slope| ≥ , in This represents the slope of the minimum change in throttle opening;

[0014] 1-3) The time difference between rapidly pressing the accelerator and rapidly releasing the accelerator is ≤ ,in This refers to the downshifting / gear shifting time.

[0015] Furthermore, the slope of the throttle opening change is obtained according to the following steps:

[0016] 2-1) While the vehicle is traveling at a stable speed, depress the accelerator pedal at the fastest possible speed and record the time difference between the accelerator pedal opening and 100%. ;

[0017] 2-2) Repeat step 2-1) with multiple people and record the time difference between 0% and 100% throttle opening. ;

[0018] 2-3) Calculate the average time difference from 0% to 100% throttle opening. :

[0019]

[0020] Obtain the minimum slope of throttle opening change :

[0021] .

[0022] Furthermore, the cumulative counter is reset to zero when any of the following conditions are met:

[0023] a) The entire vehicle is powered off;

[0024] b) The target gear correction conditions in step S2 are met.

[0025] The advantages of this invention are:

[0026] This invention effectively solves the problem of engine "air blowing" and vehicle vibration caused by changing the intention to shift gears when the accelerator is pressed and released suddenly under certain conditions. It reduces the timing of triggering upshifts and downshifts, thereby reducing the number of frequent upshifts and downshifts. Attached Figure Description

[0027] Figure 1 This is a flowchart of the present invention. Detailed Implementation

[0028] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0029] The specific implementation steps of the target gear correction method for a dual-clutch transmission of the present invention are as follows:

[0030] S1, during the process of driving at a stable speed, identify the situation of sudden pressing and releasing of the accelerator, record and count the cumulative number of times;

[0031] S2, Target gear adjustment condition judgment;

[0032] S3, target gear adjustment.

[0033] In step S1, if all of the following conditions are met, the system is identified as experiencing a sudden acceleration and deceleration of the accelerator pedal, and the cumulative counter is incremented by 1:

[0034] 1-1) Throttle opening condition: Throttle opening ≥ 100° when accelerator is depressed ,in This is the minimum throttle opening that triggers a downshift at this stable vehicle speed, which can be found in the shift map; the throttle opening during the release of the accelerator should be... Reduced to 0%;

[0035] 1-2) |Throttle opening change slope| ≥ , in This represents the slope of the minimum change in throttle opening;

[0036] 1-3) The time difference between rapidly pressing the accelerator and rapidly releasing the accelerator is ≤ ,in This refers to the downshifting / gear-shifting time.

[0037] The slope of the throttle opening change is obtained by following these steps:

[0038] 2-1) While the vehicle is traveling at a stable speed, depress the accelerator pedal at the fastest possible speed and record the time difference between the accelerator pedal opening and 100%. ;

[0039] 2-2) Repeat steps 2-1) above with multiple people (≥5 people) and record the time difference between 0% and 100% throttle opening. ;

[0040] 2-3) Calculate the average time difference from 0% to 100% throttle opening. :

[0041]

[0042] Obtain the minimum slope of throttle opening change :

[0043] .

[0044] In step S2, the target gear correction condition should meet the following: the cumulative counter count ≥ N times, where N is determined based on different customer needs, for example, 5 times.

[0045] The cumulative counter is reset to zero when any of the following conditions are met:

[0046] 1) The entire vehicle is powered off;

[0047] 2) The target gear correction conditions in step S2 are met.

[0048] In step S3, during the emergency acceleration scenario, the target downshift gear correction method is target gear + A, where A ≤ (current gear - target gear). The value of A should be determined based on customer requirements. For example, the value of A is 2.

[0049] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications made to the present invention by those skilled in the art without departing from the spirit of the present invention shall fall under the protection of the present invention.

Claims

1. A method for correcting the target gear position of a dual-clutch transmission, characterized in that, Includes the following steps: S1, during the process of driving at a stable speed, identify the situation of sudden pressing and releasing of the accelerator, record and count the cumulative number of times; When all of the following conditions are met, the system is identified as experiencing a sudden acceleration and deceleration of the accelerator pedal, and the cumulative counter increments by 1: 1-1) Throttle opening condition: Throttle opening ≥ 100° when accelerator is depressed ,in This is the minimum throttle opening that triggers a downshift at this stable vehicle speed, obtained by looking up the shift map. The throttle opening during the release of the accelerator should be... Reduced to 0%; 1-2) |Throttle opening change slope| ≥ ,in This represents the slope of the minimum change in throttle opening; 1-3) The time difference between rapidly pressing the accelerator and rapidly releasing the accelerator is ≤ ,in This refers to the downshifting / gear-shifting time; The slope of the throttle opening change is obtained according to the following steps: 2-1) While the vehicle is traveling at a stable speed, depress the accelerator pedal at the fastest possible speed and record the time difference between the accelerator pedal opening and 100%. ; 2-2) Repeat step 2-1) with multiple people, and record the time difference between the throttle opening from 0% to 100%. ; 2-3) Calculate the average time difference from 0% to 100% throttle opening. : ； Obtain the minimum slope of throttle opening change : ； S2, Target gear adjustment condition judgment: The cumulative counter count is ≥ N times, where N is determined based on different customer needs; The cumulative counter is reset to zero when any of the following conditions are met: a) The entire vehicle is powered off; b) The target gear correction condition in step S2 is met; S3, Target Gear Correction: Under the condition of sudden acceleration, the target downshift gear correction method is target gear + A, where A ≤ (current gear - target gear). The value of A is determined based on customer needs. This effectively solves the problem of engine dry blowing under the condition of sudden acceleration and deceleration and the problem of vehicle vibration caused by changing the intention to shift gears, reducing the triggering of upshifts and downshifts, thereby reducing the number of frequent upshifts and downshifts.

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