A distributed electric vehicle yaw stability control method and system

Abstract

The invention discloses a distributed electric vehicle yaw stability control method and system. The distributed electric vehicle yaw stability control method includes the steps that a road surface adhesion coefficient of the road surface on which a vehicle is and the state data of the vehicle at current time are obtained; a centroid inclined angle-centroid inclined angle velocity phase plane diagram corresponding to the road surface on which the vehicle is is determined based on the road adhesion coefficient; a maximum stable area and a minimum stable area of the phase plane diagram are determined; and the positions of phase trajectory points of the vehicle in the phase plane diagram in a current state are determined; a centroid inclined angle weight coefficient is determined according to the positions; the expected yaw angular velocity and expected centroid inclined angle of the vehicle are calculated; a sliding mode surface switching function is established; according to the state data, the centroid inclined angle weight coefficient, the expected yaw angular acceleration and the expected centroid inclined angle velocity and the sliding mode surface switching function, a desired additional yaw moment is calculated; and the steering of the vehicle at the current moment is controlled based on the expected additional yaw moment. According to the distributed electric vehicle yaw stability control method and system, the stability degree of the vehicle can be accurately judged, and the steady-state steering of the electric vehicle is realized.

Description

technical field [0001] The invention relates to the technical field of vehicle safety control, in particular to a distributed electric vehicle yaw stability control method and system. Background technique [0002] Distributed drive electric vehicles have four independently controllable drive units. Due to the configuration of this redundant execution structure, the drive can be realized by distributing and controlling the output torque of the four wheels. Due to the different output torques on both sides of the vehicle, a The direct yaw moment enables the vehicle to meet the longitudinal driving target while improving the steering characteristics of the vehicle and improving the handling stability of the vehicle. The distributed drive electric vehicle integrates the drive system and the braking system, and cancels the transmission components such as clutch, transmission, drive shaft, differential and half shaft on the power transmission route. Compared with the centralized d...

AI Technical Summary

Problems solved by technology

Among them, the direct yaw moment is obtained through joint control based on the yaw rate and the sideslip angle of the center of mass. Usually, the determination of the weight coefficient of the sideslip angle of the center of mass depends on the ratio of the sideslip angle of the center of mass to its threshold value, but only The accuracy of determining the driving state and degree of instability of the vehicle through the side slip angle of the center of mass is not high

Images