CN-121973773-A - Vehicle body traction control method and control system in snowfield running state

CN121973773ACN 121973773 ACN121973773 ACN 121973773ACN-121973773-A

Abstract

The invention discloses a vehicle body traction control method and a control system under a snowfield running state, wherein the ESC control module monitors parameter information under the vehicle running state through a sensor, calculates and obtains a rolling resistance coefficient through a calculation module, judges the vehicle running state, judges whether the vehicle is in a deep-snow running state, if so, calibrates a road surface and generates a slip rate offset, the ESC control module sends the slip rate offset to the traction control module to adjust the output size of the traction of the vehicle, and calculates parameter information detected and collected by the ESC control module to obtain the rolling resistance coefficient, adjusts the slip rate offset according to the change of the rolling resistance coefficient, sends the slip rate offset to the traction control system to adjust the output of the traction, so that the control precision of the traction control system on the deep-snow road surface can be improved, and the running speed of the vehicle is improved.

Inventors

CHEN JINGJIE
ZHAO TONG
HUANG PINGYU

Assignees

千顾汽车科技(江苏)有限公司

Dates

Publication Date: 20260505
Application Date: 20231221

Claims (10)

1. A vehicle body traction control method in a snowy running state, comprising: S1, an ESC control module monitors parameter information in a vehicle running state through a sensor and calculates a rolling resistance coefficient through a calculation module; s2, judging the running state of the vehicle according to the rolling resistance coefficient, judging whether the vehicle is in a deep snow running state, if so, calibrating the road surface, generating a slip rate offset, and if not, returning to the step S1 to continue monitoring; And S3, the ESC control module sends the slip rate offset to a traction control module and activates a deep snow mode zone bit, and the traction control module adjusts the output size of the traction of the vehicle according to the slip rate offset.
2. The method for controlling traction of a vehicle body in a snowy driving state according to claim 1, further comprising, in the step S1: S11, the ESC control module acquires the current whole vehicle driving torque and whole vehicle braking torque of the vehicle, and monitors the current vehicle acceleration and gradient value through a sensor; and S12, calculating the rolling resistance coefficient of the vehicle according to the calculation module, and obtaining a more accurate rolling resistance coefficient by a recursive least square method.
3. The method for controlling traction of a vehicle body in a snowy driving state according to claim 1, wherein the calculating module calculates a rolling resistance coefficient according to the following formula: Ma=(T1/R)-(T2/R)-(Mα)-(kMG); Wherein M is the mass of the whole vehicle, a is the acceleration of the vehicle, T1 is the driving torque of the whole vehicle, T2 is the braking torque of the whole vehicle, R is the radius of the tire, alpha is the gradient value, k is the rolling resistance coefficient, and G is the gravitational acceleration.
4. The method for controlling traction of a vehicle body in a snowy driving state according to claim 1, further comprising, in the step S2: s21, the ESC control module judges the running state of the vehicle, and when the vehicle speed is smaller than a first threshold value, the opening of an accelerator pedal is larger than a second threshold value, the rolling resistance coefficient is smaller than a third threshold value, the gear of the vehicle is a forward gear, and the vehicle is judged to be in a deep snow running state; And S22, calibrating the road surface if the vehicle is in a deep snow running state, generating a rolling resistance coefficient-slip rate offset table, and outputting the slip rate offset.
5. The method for controlling traction of a vehicle body in a snowy driving state according to claim 4, wherein the first threshold value is 8.3m/s, the second threshold value is 15 degrees, and the third threshold value is 0.3.
6. The method for controlling traction of a vehicle body in a snowy driving state according to claim 1, further comprising, in the step S3: S31, the traction control module receives the slip rate offset, improves traction output and generates a deep snow mode mark signal; and S32, the deep snow mode flag bit receives the deep snow mode flag signal to activate, and prompts through a flag.
7. The method for controlling traction of a vehicle body in a snowy driving state according to claim 1, wherein the rolling resistance coefficient is in a range of 0.03 to 0.3 and the slip ratio offset is less than 0.1 in a deep-snowy driving state.
8. The method for controlling traction of a vehicle body in a snowy driving state according to claim 1, wherein the sensor is a six-axis sensor.
9. A vehicle body traction control system in a snowy running state, characterized in that the control system is adapted to the control method according to any one of the preceding claims 1-8, comprising: the ESC control module (1) monitors parameter information in a vehicle running state and collects vehicle acceleration and gradient values; The calculation module (2) calculates according to the vehicle design parameters and parameter information acquired by monitoring to obtain a rolling resistance coefficient and sends the rolling resistance coefficient to the ESC control module (1) to generate a slip rate offset; the running judgment module (3) is used for calibrating the road surface of the vehicle according to the calculated rolling resistance coefficient and judging whether the vehicle is in a deep snow running state or not; And the traction control module (4) is used for receiving the slip rate offset and controlling traction according to the slip rate offset when the vehicle is in a deep snow running state.
10. The system according to claim 9, wherein the calculation module (2) performs fitting calculation of the calculated rolling resistance coefficient by a least-squares recursive method.

Description

Vehicle body traction control method and control system in snowfield running state Technical Field The invention relates to the technical field of automobile brake control, in particular to a vehicle body traction control method and a vehicle body traction control system in a snowfield running state. Background With the continued development of vehicle motorization, accurate control of the vehicle has become increasingly important. In the existing traction control method, the characteristics of the deep snow road surface cannot be quickly identified, so that the torque is too much in the deep snow road condition, and the traction control system cannot accurately control the output traction, so that the vehicle runs slowly. The patent publication CN109080623B provides a snowfield running control system of a hybrid vehicle, in which a main control unit receives a snowfield mode start signal generated by triggering a snowfield mode switch and controls the vehicle to enter a snowfield mode, and transmits a snowfield mode request signal to a sub-control unit in the snowfield mode, a TCU controls a shift timing of the vehicle to match with a running state of the power system in response to the snowfield mode request signal, an ESP controls the vehicle to shorten a vehicle braking distance and initiate a torque down request in response to the snowfield mode request signal, and an EAS reduces a suspension height in response to the snowfield mode request signal. The method improves the stability of vehicle chassis control by reducing the torque, but still leads to inaccurate output control of the traction force of the vehicle in the process of running on the snow, and is difficult to flexibly adjust the running speed of the vehicle in the snow. Disclosure of Invention The invention aims to solve the defects in the prior art, and provides a vehicle body traction control method and a vehicle body traction control system in a snowfield running state. In order to achieve the above purpose, the invention adopts the following technical scheme that the vehicle body traction control method under the snowfield running state comprises the following steps: S1, an ESC control module monitors parameter information in a vehicle running state through a sensor and calculates a rolling resistance coefficient through a calculation module; s2, judging the running state of the vehicle according to the rolling resistance coefficient, judging whether the vehicle is in a deep snow running state, if so, calibrating the road surface, generating a slip rate offset, and if not, returning to the step S1 to continue monitoring; And S3, the ESC control module sends the slip rate offset to a traction control module and activates a deep snow mode zone bit, and the traction control module adjusts the output size of the traction of the vehicle according to the slip rate offset. As a further description of the above technical solution, in the step S1, the method further includes: S11, the ESC control module acquires the current whole vehicle driving torque and whole vehicle braking torque of the vehicle, and monitors the current vehicle acceleration and gradient value through a sensor; and S12, calculating the rolling resistance coefficient of the vehicle according to the calculation module, and obtaining a more accurate rolling resistance coefficient by a recursive least square method. As a further description of the technical scheme, the method for calculating the rolling resistance coefficient by the calculation module comprises the following steps of (Ma= (T1/R) - (T2/R) - (Mα) - (kMG); Wherein M is the mass of the whole vehicle, a is the acceleration of the vehicle, T1 is the driving torque of the whole vehicle, T2 is the braking torque of the whole vehicle, R is the radius of the tire, alpha is the gradient value, k is the rolling resistance coefficient, and G is the gravitational acceleration. As a further description of the above technical solution, in the step S2, the method further includes: s21, the ESC control module judges the running state of the vehicle, and when the vehicle speed is smaller than a first threshold value, the opening of an accelerator pedal is larger than a second threshold value, the rolling resistance coefficient is smaller than a third threshold value, the gear of the vehicle is a forward gear, and the vehicle is judged to be in a deep snow running state; And S22, calibrating the road surface if the vehicle is in a deep snow running state, generating a rolling resistance coefficient-slip rate offset table, and outputting the slip rate offset. As a further description of the above technical solution, the first threshold is 8.3m/s, the second threshold is 15 °, and the third threshold is 0.3. As a further description of the above technical solution, in the step S3, the method further includes: S31, the traction control module receives the slip rate offset, improves traction output and generates a deep snow mode mark si