CN-115899246-B - Control method and control device of hydraulic torque converter and vehicle

CN115899246BCN 115899246 BCN115899246 BCN 115899246BCN-115899246-B

Abstract

The embodiment of the application discloses a control method, a control device and a vehicle of a hydraulic torque converter, wherein the control method of the hydraulic torque converter comprises the steps of obtaining a speed ratio of the torque converter; and controlling unlocking and locking states of the hydraulic torque converter based on the opening degree of an accelerator and the vehicle speed under the condition that the speed ratio of the torque converter is larger than a speed ratio threshold value. When the vehicle load is small, the speed difference between the pump wheel and the turbine is small, the locking impact is small, and under the condition, the unlocking and locking of the hydraulic torque converter are controlled by the opening of the accelerator and the speed of the vehicle, and meanwhile, the fuel economy is also realized.

Inventors

ZHOU SHEN
YANG LEI
LI CHUNFENG

Assignees

湖北三江航天万山特种车辆有限公司
湖北航天技术研究院特种车辆技术中心

Dates

Publication Date: 20260512
Application Date: 20220915

Claims (9)

1. A control method of a torque converter, characterized by comprising: Acquiring a torque converter speed ratio; Controlling the unlocked and locked state of the torque converter based on an accelerator opening and a vehicle speed when the torque converter speed ratio is greater than a speed ratio threshold, comprising: Under the condition that the speed ratio of the torque converter is larger than a speed ratio threshold value, acquiring a first torque curve which is output by the engine and the hydraulic torque converter under different accelerator opening degrees in a combined working mode; Acquiring a second torque curve of the engine working independently under different throttle openings; acquiring a first intersection point of the first torque curve and the second torque curve under the same coordinate system; Connecting a plurality of first intersection points to obtain a locking curve; acquiring a third torque curve output by wheels under different gears; acquiring a second intersection point of a third torque curve of two adjacent gears under the same coordinate system; Connecting the second intersection points between two adjacent gears to obtain an upshift curve; and determining unlocking and locking states of the hydraulic torque converter based on the locking curve and the upshift curve.
2. The control method according to claim 1, wherein, The speed ratio of the torque converter is the ratio of the turbine speed to the pump impeller speed, and the value of the speed ratio threshold is 0.65-0.85.
3. The control method according to claim 1, characterized by further comprising: the torque converter is controlled to remain in an unlocked state when the torque converter speed ratio is less than or equal to a speed ratio threshold.
4. The control method according to claim 1, characterized in that the step of determining the unlock and lock-up state of the torque converter based on the lock-up curve and the upshift curve includes: Under the same coordinate system, when the first vehicle speed corresponding to the locking curve is greater than the second vehicle speed corresponding to the upshift curve and the phase difference is greater than a first threshold value, controlling the hydraulic torque converter to be maintained in a locking state; Under the same coordinate system, when the first vehicle speed corresponding to the locking curve is smaller than the second vehicle speed corresponding to the upshift curve and the phase difference is larger than the first threshold value, controlling the hydraulic torque converter to be maintained in an unlocking state; And under the same coordinate system, when the difference between the first vehicle speed corresponding to the locking curve and the second vehicle speed corresponding to the upshift curve is smaller than or equal to the first threshold value, controlling the hydraulic torque converter to maintain in the current state.
5. The control method according to claim 4, characterized in that the step of controlling the unlock and lock-up state of the torque converter based on an accelerator opening degree and a vehicle speed in the case where the torque converter speed ratio is greater than a speed ratio threshold value further includes: Acquiring an unlocking curve based on the locking curve; acquiring a downshift curve based on the upshift curve; And determining the unlocking and locking states of the hydraulic torque converter based on the unlocking curve and the downshift curve.
6. The control method according to claim 5, wherein, The step of obtaining an unlocking curve based on the locking curve comprises the following steps: under the same coordinate system, translating the locking curve to a first scale according to the direction of reducing the vehicle speed to obtain the unlocking curve; the step of obtaining a downshift profile based on the upshift profile includes: And under the same coordinate system, translating the upshift curve by a second scale according to the direction of vehicle speed reduction to obtain the unlocking curve.
7. The control method according to claim 6, wherein, The step of determining the unlock and lock-up state of the torque converter based on the unlock curve and the downshift curve includes: Under the same coordinate system, when the third vehicle speed corresponding to the unlocking curve is greater than the fourth vehicle speed corresponding to the downshift curve and the phase difference is greater than a second threshold value, controlling the hydraulic torque converter to be maintained in an unlocking state; Under the same coordinate system, when the third vehicle speed corresponding to the unlocking curve is smaller than the fourth vehicle speed corresponding to the downshift curve and the phase difference is larger than the second threshold value, controlling the hydraulic torque converter to be maintained in a locked state, and when the vehicle reaches the downshift curve, controlling the hydraulic torque converter to be switched to the unlocking state; And under the same coordinate system, when the difference between the third vehicle speed corresponding to the unlocking curve and the fourth vehicle speed corresponding to the downshift curve is smaller than or equal to a second threshold value, controlling the hydraulic torque converter to maintain in the current state.
8. A control apparatus, characterized by comprising: A memory storing a computer program; A processor executing the computer program; Wherein the processor, when executing the computer program, implements the control method according to any one of claims 1 to 7.
9. A vehicle, characterized by comprising: the control device of claim 8; and the control device is connected with the hydraulic torque converter and is used for controlling the hydraulic torque converter.

Description

Control method and control device of hydraulic torque converter and vehicle Technical Field The embodiment of the application relates to the technical field of vehicle control, in particular to a control method of a hydraulic torque converter, a control device and a vehicle. Background The hydraulic torque converter is commonly arranged on heavy vehicles and engineering machinery, so as to improve the comprehensive fuel economy of a transmission system, wherein the hydraulic torque converter is provided with a locking function and converts hydraulic transmission into mechanical transmission. The torque converter lockup control is usually performed by single-parameter lockup control of the engine speed or the vehicle speed, or by double-parameter control of the vehicle speed and the accelerator opening. The single-parameter control design is simple, because only single-parameter control with the speed or the rotating speed of an engine is adopted, the vehicle can only consider dynamic performance, economy and comfort under partial medium and high load working conditions, and under other working conditions, because the hydraulic torque converter is kept unlocked, the working rotating speed of the engine is high, the noise is large, the fuel economy and the comfort are poor, and the double-parameter control adopts the opening degree of an accelerator and the speed control to unlock, on heavy vehicles and engineering machinery, the vehicle is heavy, the power reserve coefficient of the vehicle is low, the road condition is bad, and the double-parameter locking based on the accelerator and the rotating speed is adopted, so that locking impact under common working conditions is difficult to consider, the comfort is reduced, and meanwhile, the larger locking impact causes adverse effects on the reliability of a transmission system. Disclosure of Invention The present invention aims to solve at least one of the technical problems existing in the prior art or related art. To this end, a first aspect of the invention provides a control method of a torque converter. A second aspect of the present invention provides a control apparatus. A third aspect of the invention provides a vehicle. In view of this, a first aspect according to an embodiment of the present application proposes a control method of a torque converter, including: Acquiring a torque converter speed ratio; And controlling unlocking and locking states of the hydraulic torque converter based on the opening degree of an accelerator and the vehicle speed under the condition that the speed ratio of the torque converter is larger than a speed ratio threshold value. In one possible embodiment, the torque converter speed ratio is the ratio of turbine speed to impeller speed, and the ratio threshold has a value of 0.65 to 0.85. In a possible embodiment, the control method further includes: the torque converter is controlled to remain in an unlocked state when the torque converter speed ratio is less than or equal to a speed ratio threshold. In one possible embodiment, the step of controlling the unlock and lock-up state of the torque converter based on the accelerator opening and the vehicle speed in the case where the torque converter speed ratio is greater than a speed ratio threshold value includes: Under the condition that the speed ratio of the torque converter is larger than a speed ratio threshold value, acquiring a first torque curve which is output by the engine and the hydraulic torque converter under different accelerator opening degrees in a combined working mode; Acquiring a second torque curve of the engine working independently under different throttle openings; acquiring a first intersection point of the first torque curve and the second torque curve under the same coordinate system; Connecting a plurality of first intersection points to obtain a locking curve; acquiring a third torque curve output by wheels under different gears; acquiring a second intersection point of a third torque curve of two adjacent gears under the same coordinate system; Connecting the second intersection points between two adjacent gears to obtain an upshift curve; and determining unlocking and locking states of the hydraulic torque converter based on the locking curve and the upshift curve. In one possible embodiment, the step of determining the unlock and lock-up state of the torque converter based on the lock-up curve and the upshift curve includes: Under the same coordinate system, when the first vehicle speed corresponding to the locking curve is greater than the second vehicle speed corresponding to the upshift curve and the phase difference is greater than a first threshold value, controlling the hydraulic torque converter to be maintained in a locking state; Under the same coordinate system, when the first vehicle speed corresponding to the locking curve is smaller than the second vehicle speed corresponding to the upshift curve and the phase difference is large