Reach On Anti-slip Regulation Of Electric Vehicle Driven By Wheel-side Motor

The growing global environmental problems have forced major automakers to seek new sustainable solutions,and electric vehicles have emerged.Different from the centralized driving electric vehicle,the distributed driving method can better take advantage of the electric vehicle.Among them,the four-wheel side motor distributed driving vehicle has the most outstanding performance.On the basis of retaining the structure of the traditional automobile chassis,four motors are used to drive the wheels respectively,which can better improve the dynamic performance of the vehicle.Equipped with advanced electronic control technology,it greatly enhances the active safety and handling performance of the vehicle.In this paper,the distributed drive vehicle of wheel-side motor is taken as the research object,and the driving anti-skid control strategy of the vehicle is studied.Firstly,undering the guidance of modularization,in this paper,a vehicle dynamics simulation platform for distributed drive electric vehicles driven by wheel-side motors is built.The Carsim and Simulink software are combined through the input and output interface,it integrates the distributed driving vehicle model based on the modification of conventional vehicle in Carsim and the simplified model of wheel-side motor,power transmission system and tue anti-slip regulation model built in Simulink.+Secondly,after analyzing the principle of acceleration slip regulation control,the anti-skid control strategy of motor output torque control for wheel slip rate is determined,wheich ensures the tracking performance of the vehicle to the optimal slip ratio,makes full use of the road adhesion coefficient,and improves the vehicle's dynamic performance and stability of the vehicle.In this paper,two control algorithm are proposed: a vehicle speed observer based on the extended state observation algorithm estimates the longitudinal velocity of the vehicle,which provides a basis for the acquisition of real-time wheel slip rate,and uses variable structure and fuzzy variable structure algorithm to achieve slip rate control;a slip ratio observer to achieve real-time acquisition of slip rate,and a typical PID algorithm to achieve slip ratio control,in order to achieve the purpose os anti-skid.In order to ensure the linear stability of vehicle acceleration,a simple distribution control strategy for the output torque of four motors is designed in this paper.Finally,the proposed algorithm is verified by simulation.The slip ratio control algorithm is simulated and validated for linear acceleration of vehicles on single adhesion coefficient road and docking road with sudden change of adhesion coefficient using the co-simulation platform.The simulation results show that the speed observer proposed in this paper can effectively track the vehicle speed under different road conditions,and the tracking error is within acceptable;the proposed slip rate control algorithm is effective under different simulation conditions and can meet the requirements of acceleration slip regulation control.Through the simulation of vehicle linear acceleration on the opposite road surface,it is verified that the proposed torque allocation control strategy can ensure the vehicle linear driving performance.At the end of the paper,the general layout and construction process of the experimental platform are briefly described,including the introduction of the general layout scheme,chassis structure,power transmission system,power drive system,etc.,which lays the foundation of mechanical platform for subsequent practical testing.