Research On Platoon Control Of Intelligent Electric Vehicles Considering Vehicle Stability

Compared with the traditional fuel vehicles,electric vehicles are more energy-saving and environmental protection,which can greatly reduce environmental pollution.Therefore,our country has begun to vigorously promote the popularization of new energy electric vehicles.In order to further alleviate traffic pressure caused by the increase of vehicle ownership,improve road utilization,and prevent traffic accidents,the research of intelligent electric vehicle platoon control has also become an indispensable part of future intelligent transportation.In this paper,the intelligent electric vehicle platoon is taken as the research object.Considering that when the vehicle platoon moves longitudinally and laterally at high speed on wet or ice-snow roads,the following vehicle may not only be dangerous due to tire slip or sideslip,but also be unstable if the motor fails,resulting in serious traffic accidents.Therefore,in order to realize the longitudinal and lateral control of vehicle platoon and improve the longitudinal and lateral stability of following vehicles,this paper mainly designs the longitudinal and lateral controller,the longitudinal and lateral stability controller and the fault-tolerant controller based on the model predictive control(MPC)theory and the sliding mode control(SMC)theory.The main research contents include the following aspects:(1)The longitudinal control of vehicle platoon is studied.First,the longitudinal spacing strategy of vehicle platoon is designed.Then,a robust MPC longitudinal controller is designed by establishing the longitudinal model of vehicle platoon,which can improve the longitudinal control accuracy of vehicle platoon.In addition,considering the longitudinal stability of the following vehicle,a slip rate controller based MPC is designed by establishing the tire slip rate model of the following vehicle,which can prevent the tire slip and ensure the longitudinal stability of the following vehicle.(2)The lateral control of the following vehicle is studied.Aiming at the overtaking or lane changing conditions of the leader vehicle in the vehicle platoon,a lateral controller based on MPC is designed by establishing the plane dynamic model of the following vehicle,which can ensure that the following vehicle track the real-time trajectory of the leader vehicle,so as to realize the lateral motion control of the vehicle platoon.In addition,a second-order SMC controller with disturbance observer is designed to reduce the control chattering caused by the traditional first-order SMC and ensure the lateral stability of the following vehicle.(3)Fault-tolerant control of motors for following vehicles is studied.Considering the stability problem of the following vehicle when motor fails,a SMC fault-tolerant controller is designed by combining the designed second-order SMC controller and the optimal allocation control algorithm.The optimal distribution control algorithm is to substitute the motor fault as a fault factor into the calculation,and reasonably distribute the yaw torque output by the second-order SMC controller and the torque output by the longitudinal controller.Finally,the practical application of the designed controller is verified by the built controller hardware-in-loop system.(4)The longitudinal control and lateral control of vehicle platoon are tested in real vehicle.First,the vehicle platoon platform is built,and the vehicle platoon communication framework is designed based on ROS.Then,the longitudinal controller and the lateral controller are designed by Simulink.Finally,the real vehicle platform is tested under straight line condition and bend condition respectively,and the effectiveness of the longitudinal and lateral controller is verified.