Nonlinear analysis method for steering stability of electric automobile

Abstract

The invention discloses a nonlinear analysis method for steering stability of an electric automobile. A nonlinear dynamics model capable of describing steering of the electric automobile is established, a nonlinear differential equation is constructed, then on the basis of an adiabatic elimination principle, order reduction processing is performed on the constructed nonlinear differential equation for steering of the electric automobile, in this way, fast relaxation parameters in a system are eliminated, and a simplified nonlinear differential equation is obtained; finally, on the basis of an isoclinic line principle, a multi-step recurrence method is adopted for drawing the phase trajectory of the nonlinear dynamics system for steering of the electric automobile, the balance state, stability precision and stability of the system are visually reflected, and the stability of the electric automobile in the steering process at different speeds and turning angles is analyzed.

Description

technical field [0001] The invention relates to a nonlinear analysis method for the stability of an electric vehicle during steering, and belongs to the technical field of vehicle steering stability analysis. Background technique [0002] Under the extreme conditions of high speed and large steering, with the rapid increase of lateral acceleration, the tires enter the strong nonlinear region, the linear relationship between steering force and slip angle no longer satisfies, and the tire force is saturated. Steering behavior cannot be determined, and it is difficult to accurately estimate its steering behavior and stable region using traditional linear analysis methods. At this time, the steering characteristics of electric vehicles need to be studied from the perspective of nonlinear dynamics. [0003] The traditional nonlinear analysis methods for steering stability of electric vehicles are mostly limited to the two-degree-of-freedom steering model, which cannot fully refle...

AI Technical Summary

Problems solved by technology

[0002] Under the extreme conditions of high speed and large steering, with the rapid increase of lateral acceleration, the tires enter the strong nonlinear region, the linear relationship between steering force and slip angle no longer satisfies, and the tire force is saturated. The steering behavior cannot be determined, and it is difficult to accurately estimate its steering behavior and stable region by using traditional linear analysis methods. At this time, the steering characteristics of electric vehicles need to be studied from the perspective of nonlinear dynamics

[0003] The traditional nonlinear analysis methods for steering stability of electric vehicles are mostly limited to the two-degree-of-freedom steering model, which cannot fully reflect the high-order and complex steering process of the car. However, the Lyapunov stability analysis method for high-order nonlinear systems, The process of constructing its Lyapunov function is extremely complicated, and the analysis period is long

Images