Research On Yaw-Roll Stability Control Of Distributed Drive Electric Vehicle

Based on the characteristics of high power transmission efficiency and independently controllable torque of each wheel of distributed drive electric vehicle,this paper focuses on the research of yaw-roll stability control strategy to improve the lateral and lateral stability of the vehicle.The main research contents of this paper are as follows:Firstly,the vehicle dynamics and wheel dynamics in the process of vehicle movement are analyzed.Considering the steering characteristics of the driver in the closed-loop control system,the trajectory preview driver model is built,which provides a verification platform for the follow-up control strategy.Yaw-roll stability control strategy adopts hierarchical control architecture,which consists of three parts:(1)parameter identification module: the measurement process is limited by position and cost in practice,and unscented Kalman filter is proposed to estimate the key parameters affecting roll-roll stability;(2)Control module:including stability judgment,yaw moment decision and ideal state parameter calculation.Under dangerous working conditions,the vehicle calculates the yaw moment and driving moment required by the vehicle according to the current running state;(3)Execution module: distribute the additional yaw moment needed to maintain the stability of the vehicle to four wheels with driving/braking moment.The state estimation model and yaw-roll stability control strategy model are established by MATLAB/Simulink,and the simulation is carried out with the vehicle model in Carsim to verify the stability control strategy.In this paper,the combined control strategy of yaw and roll is divided into uncontrolled mode,simple yaw control mode,unilateral tilt control mode and comprehensive yaw and roll control mode(two kinds of instability occur at the same time,and the roll state is controlled preferentially).The simulation results show that the control method can ensure the yaw stability of vehicles under dangerous conditions.Through torque optimization distribution,the vehicle speed can be kept constant in the control process,which can meet the dynamic requirements of the vehicle,and the roll state can be monitored and controlled to prevent the occurrence of roll instability.Simulation results show that the control algorithm ensures the effectiveness of distributed drive electric vehicles in yaw-roll stability control.