Research On Energy Flow Testing And Management Strategy Of Pure Electric Vehicles

Recently,with the increasingly serious problems of energy resource and global environment,new driving technologies and alternative fuels are being studied and utilized frequentlier.Pure electric vehicles are favored by market users and the government,and have become a battleground for major manufacturers.This paper is based on the development of a pure electric vehicle.A pure electric vehicle performance model is established by GT-Suite to study the influence of different environmental factors on the contribution of regenerative braking to the energy efficiency of the vehicle and conduct a reasonable and effective evaluation.The main contents are as follows:(1)Design the power system based on the basic parameters of the vehicle and match the battery and motor.Establish the driving strategy and energy management strategy of the pure electric vehicle.(2)Carry out vehicle dynamic performance test and energy flow test.The test results show that the performance indicators of the entire vehicle meet the design requirements,and the energy consumption of the entire NEDC operating range continues to decrease first and then remains relatively stable and slowly decreases.(3)Establish a mathematical model and quantitatively evaluate the contribution of regenerative braking energy efficiency.The test data shows that the energy consumption contribution rate and mileage contribution rate of regenerative braking under NEDC operating conditions reach 23.76% and 31.16%.(4)Build a simulation model based on GT-Suite simulation software.The simulation model has good accuracy: Under a single NEDC,the relative error of vehicle speed and battery SOC is less than 8%,and the absolute error of motor torque is within 20 Nm.(5)Explore the influence of different working conditions(WLTC,US06,FTP75,CLTC,NEDC and JC08)and road gradients(0°,2° and 4°)on the contribution of regenerative braking and the energy efficiency of the vehicle.The simulation results show that: The contribution rates of JC08 and WLTC are the highest and the lowest respectively,and the contribution rates of road slopes of 2° and4° are reduced by 78.78% and 94.17% on average.