Research On Brake Slip Rate Control Of Distributed Electric Vehicle Based On Multi-agent

With the progress of science and technology and people’s attention to environmental issues,new energy electric vehicles have developed rapidly with the characteristics of zero pollution emission and low energy consumption.The vigorous development of the automotive industry also makes driving safety more worthy of attention,and braking stability is an important part of driving safety.In this paper,four-wheel hub motor driven electric vehicle is taken as the research object.For the electric vehicle brake driving situation,the slip ratio control is a nonlinear and time-varying complex system,the braking slip control of vehicle is studied.Firstly,the working principle of anti-skid braking is analyzed,and the basic braking dynamic model is established.The new method is proposed to set up a fuzzy rule based on the ?-? curve of the marked pavement and establish a fuzzy pavement identifier to obtain the optimal slip rate of pavement in real time.Two control methods are proposed to control the slip rate of four-wheel brake.The first method is based on the general sliding mode multi-agent control algorithm.Firstly,the sliding mode controller of a single wheel is established.According to the connection structure of electric vehicle and the principle of internal working communication,a virtual leader agent is introduced to obtain the optimal slip rate of road surface,and the topological structure composed of four wheels and virtual leaders is obtained.A new control rate is designed by combining multi-agent with ordinary sliding mode control algorithm,and the Lyapunov stability of the system is proved.The second method is based on the multi-agent control algorithm of non-singular terminal sliding mode.Considering the load transfer phenomenon in the process of vehicle braking,the vehicle system is re-modeled.Considering external interference and measurement error,the multi-agent control algorithm of non-singular terminal sliding mode is designed.The genetic algorithm is used to optimize the design parameters of sliding surface to improve the reliability of control strategy.Finally,a joint simulation platform for brake slip control of CarSim-Matlab/Simulink electric vehicle is built,and the vehicle is simulated on standard uniform pavement and dry cement pavement.The simulation results show that the proposed algorithm can achieve good control effect,meet the stability requirements of vehicle braking,effectively suppress the occurrence of wheel lock-up,and improve the robustness of the system.Among them,the control effect of non-singular terminal sliding mode multi-agent based on genetic algorithm optimization is better,which makes the braking time and braking distance of vehicle shorter.