Calculation method, system and vehicle for predicting vehicle speed during vehicle speed pi adjustment process

Abstract

The invention provides a method and system for predicating a vehicle speed in the vehicle speed PI adjusting process and a vehicle. The method for predicating the vehicle speed in the vehicle speed PIadjusting process comprises the following steps of obtaining a motor rotation speed of the vehicle, four wheel speeds, a first vehicle speed calculated by an anti-lock braking system and a second vehicle speed collected by a vehicle speed sensor; judging whether the motor rotation speed, the four wheel speeds, the first vehicle speed and the second vehicle speed meet a preset condition or not; ifso, calculating the average wheel speed of three smaller wheel speeds in the four wheel speeds and using a vehicle speed corresponding to the average wheel speed as the current vehicle speed of the vehicle; judging whether an accelerated speed of the vehicle is higher than zero or not; and if so, obtaining the predicated vehicle speed at a target time according to the current vehicle speed and the accelerated speed. According to the method for predicating the vehicle speed in the vehicle speed PI adjusting process, as the vehicle slipping situation is taken into consideration, more accurate and reliable predicated vehicle speeds can be obtained so as to guarantee the torque limiting reliability and enhance the vehicle safety.

Description

technical field [0001] The invention relates to the technical field of automobiles, in particular to a calculation method, system and vehicle for predicting vehicle speed in the process of vehicle speed PI adjustment. Background technique [0002] For pure electric vehicles, in order to prevent excessive vehicle torque from causing adverse effects on the motor, power battery and various components, the VCU (Vehicle Control Unit, vehicle controller) needs to limit the vehicle torque, mainly by limiting the torque to make the vehicle speed Do not exceed the limit value. Usually, this kind of torque limit can achieve the purpose of calculating the torque limit value through PI vehicle speed adjustment, and the selection and calculation of the predicted vehicle speed in the PI (Proportion-Integral, proportional-integral) adjustment algorithm directly affect the effect of torque limit. [0003] At present, the predicted vehicle speed is basically calculated based on the current ...

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