关键词: 路面附着系数, 电动助力转向, 模糊灰预测, 助力特性曲线, 操纵性

Abstract:

To realize the red-time control of electric power steering system, grey system prediction theory was used to predict the development of system behavior, and fuzzy logic control theory was used to design an EPS fuzzy-grey predictive control system based on road with double adjustment factor. According to the difference of assist current, fuzzy reasoning was used to achieve self-adaptive adjustment of the step length. The vehicle EPS dynamic model was established based on CarSim, and the mechanical steering system and motor were established based on MATLAB. Through the joint simulation, when running on the road with high adhesion coefficient, the standard deviation of the yaw rate on a high adhesion coefficient road surface decreases from 4.564(°)/s to 2.596(°)/s. The easiness of vehicle control was improved, and the settling time of the yaw angle speed adjustment was shortened greatly, the vehicles maneuverability and safety was coordinated while steering on different adhesion coefficient road.

Key words: road adhesion coefficient, electric power steering (EPS), fuzzy grey predictive, power characteristic curve, maneuverability