| The driving mode of an automobile has a great influence on its economy and power.The existing pure electric four-wheel drive vehicles are mostly front-rear two-motor four-wheel drive vehicles.Compared with the single-motor drive system,although the economy and power performance of this configuration are slightly improved,there will be insufficient power under special working conditions.Therefore,this paper proposes a two-mode coupling drive system between axles,and conducts the following researches on this system.(1)The matching design of the dynamic system of the intershaft coupling drive system is carried out,and then the structural parameters and control parameters of the proposed intershaft dual-mode coupling drive system are optimized through the optimization algorithm.With economic optimization as the control objective and dynamic performance as the constraint condition,it can be seen from the optimization results that the driving economy of the vehicle has been improved.(2)The working characteristics of the dual-mode coupling drive system between shafts under six modes are analyzed.Then,aiming at the minimum input power of total demand,the distribution of six modes at all operating points is calculated and drawn through MATLAB programming.Based on this,the mode selection strategy based on the optimal efficiency is formulated.(3)The drive anti-slip control method is analyzed.Aiming at the problems existing in traditional SMC,the integral and differential terms are added,and the bounded sliding mode control(CSMC)control method is proposed.This method can effectively eliminate steady-state error and other problems.Then the influence of control parameters on the sensitivity of control effect is analyzed.Through simulation analysis,it is concluded that CSMC can effectively track the target slip rate and eliminate the steady-state error compared with that proposed by SMC.(4)The characteristics of the interaxle dual-mode coupling drive system driving on the ramp were analyzed,and the drive control strategy was developed.The simulation proved that compared with the front and rear axle dual-motor four-wheel drive vehicle,the vehicle equipped with the interaxle dual-mode coupling drive system had better power performance when driving on the ramp.In this paper,a dual-mode coupling drive system between axles is proposed,and mode selection and drive anti-slip control strategy are formulated for its configuration.This configuration can simultaneously improve the driving economy and power performance of pure electric vehicles.It is of important engineering value to study the dual-mode coupling drive system between axles in this paper. |
