Lateral Stability Control Of Electric Wheel Drive Vehicle Based On Chassis Coordination

Each wheel of in-wheel-motor drive vehicles(IWMDVs)have a set of driving motor,merits of which are driving/braking anti-slip control,active yaw moment control and body attitude control,etc.On the one hand,IWMDV has ability to improve the dynamic stability of the vehicle significantly,on the other hand,IWMDV is regard as the latest form of electric vehicle.With the increasing of vehicle integration and the development of advanced control technology of vehicle,it is obvious that the additive of distribution controller’s field can’t make control system performance maximization.The dissertation relies on IWMDV,an integrated theme about front wheel active steering(AFS),active yaw moment control(DYC)and active suspension roll control(ASRC)is proposed.The main contents of this research has four parts:(1)A 14-DOF dynamics coupling model,tire model,active suspension system(ASS),electric power steering system(EPS)model,second-order response model of driving system and driver’s single-point optimal preview model for IWMDVs are established.Through comparing with the simulation results of Carsim by the same parameter,the rationality of the vehicle mathematical model is verified.(2)The coupling effect between IWMDVs’ differential-drive technology(DDT),AFS and ASS and its influence mechanism on vehicle stability are analyzed.And the expected dynamic characteristics of the vehicle with different stability control systems under typical working conditions is explored,and the coupling mechanism is verified by simulation.(3)The influence of input and output of damping and stiffness system in steering transmission mechanism is analyzed quantitatively.In order to make the bottom actuators track desired position/torque,the bottom actuator controller of EPS and ASS are designed by control theory.(4)A chassis stability control strategy of IWMDVs based on chassis coordination is proposed.Model predictive control(MPC)and sliding mode control(SMC)algorithm is used to calculate the controller desired output.According the aptitude of AFS & DYC,the weight distribution method of DYC &AFS’s actual output is designed.Simulation results show the effectiveness of the proposed chassis stability control strategy.In this dissertation,aiming at the superiority of electric wheel drive technology,the chassis integration stability control strategy for IWMDVs is proposed.The simulation results show that the proposed chassis integration control strategy can better improve the stability of IWMDVs.The research of this dissertation has certain theoretical reference value and a wide range of practical application prospects for IWMDVs.