All wheel individual drive electric car traction control method and device

Abstract

The invention provides an all wheel individual drive electric car traction control method and device; the control method comprises the following steps: obtaining a tyre pressure parameter of each wheel, calculating a wheel diameter correction factor of each wheel according to the tyre pressure parameter of each wheel; calculating tyre wheel speed of each wheel according to the wheel diameter correction factor of each wheel; calculating the whole vehicle speed according to the tyre wheel speed of each wheel, if the electric car is under a driving condition, using the minimum value of the tyre wheel speed of each wheel to calculate the whole vehicle speed, if the electric car is in a braking condition, using the maximum value of the tyre wheel speed of each wheel to calculate the whole vehicle speed; using the tyre wheel speed of each wheel and the whole vehicle speed to calculate a slippage rate of each wheel; carrying out traction control at least according to the whole vehicle speed and / or the slippage rate of each wheel. The method can solve the problems that the slippage rate and the whole vehicle speed are inaccurate in calculation, thus realizing traction control of the whole vehicle.

Description

technical field [0001] The invention relates to the field of electric vehicles, in particular to a traction force control method and device for an all-wheel independently driven electric vehicle. Background technique [0002] An all-wheel independent drive electric vehicle refers to an electric drive vehicle in which all wheels are actively driven and have independent driving degrees of freedom. This type of vehicle has the characteristics of good maneuverability, simple transmission structure, quick response, high system reliability, and easy realization of complex driving force control. [0003] The vehicle speed information of the wheel-drive electric vehicle is mainly obtained from the rotational speed of each wheel drive motor after proportional conversion. Vehicle speed information is an important driving parameter of the vehicle, and plays an important role in the calculation of wheel slip rate. The slip rate is an important control parameter of the vehicle driving ...

AI Technical Summary

Problems solved by technology

On the other hand, all wheels of an all-wheel independent drive electric vehicle are actively driven wheels, which may slip or lock up. When the wheels slip severely, the wheel speed will lose the matching relationship with the actual vehicle speed.

However, the existing calculations for the vehicle speed and the traction force of each wheel are not accurate enough, especially the slip rate cannot be accurately obtained to control the vehicle slippage

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