Steering-by-wire system and control method for a wheel-drive electric vehicle

Abstract

The invention discloses a steering-by-wire steering system for a wheel-drive electric vehicle, which includes three parts, a steering wheel assembly, an ECU unit, and a steering execution assembly connected in sequence. The invention also discloses the control of the steering-by-wire system for a wheel-drive electric vehicle. method, first construct an ideal two-degree-of-freedom vehicle steering dynamics model, and establish the relationship between the vehicle state parameters yaw rate gain and lateral acceleration gain and the angular transmission ratio; then design a reasonable constant yaw angle gain and constant lateral acceleration gain , to determine the angular transmission ratio at different vehicle speeds; finally design the vehicle state parameters yaw rate and sideslip angle as the feedback at the same time, build a reliable and stable active steering controller based on PI control, the present invention solves the problems in the prior art In steer-by-wire, the mechanical coupling of the steering actuators between the wheels does not have independent steering functions, the dynamic response of the steering wheels is slow, and the vehicle handling stability is poor under severe steering conditions.

Description

technical field [0001] The invention belongs to the technical field of steering of new energy electric vehicles, and in particular relates to a steer-by-wire steering system of a wheel-drive electric vehicle, and also relates to a steering-by-wire control method of a wheel-drive electric vehicle. Background technique [0002] Electric vehicles use electricity as the power source and have the advantages of zero emissions and high energy transfer efficiency. Their key technologies continue to break through and are challenging the market position of traditional internal combustion engine vehicles. Wheel drive and independent steer-by-wire have improved the space utilization efficiency and transmission efficiency of the vehicle chassis, providing a broader space for the development of electrification, intelligence, and lightweight vehicles. [0003] Steering by wire cancels the complex mechanical structure of the traditional steering system, and all parts are connected by signal...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to provide a steer-by-wire system for a wheel-drive electric vehicle, which solves the problems in the prior art that the mechanical coupling of the steering actuators between the wheels does not have an independent steering function and the dynamic response capability of the steering wheel is poor. question

Images