Research On Braking Energy Recovery Control Strategy Of Pure Electric Commercial Vehicle

With the rapid development of the new energy vehicle industry in recent years,commercial vehicles have also entered the transition phase of electrification.Compared with traditional energy commercial vehicles,pure electric commercial vehicles have a particularly high range problem due to the limitations of current battery technology.In this paper,we design a braking energy recovery control strategy for a pure electric 4.5T light-duty truck based on a traditional internal combustion engine platform under different load conditions,aiming to improve the braking stability of the vehicle while further improving the energy utilization efficiency of the vehicle.Firstly,according to the structural parameters and basic performance indexes of the benchmark vehicle,the drive and brake system components are selected and matched,and the selected brakes are verified to meet the braking performance requirements of the vehicle while reflecting the optimization space of the original braking force distribution strategy.Secondly,the vehicle and power system are modeled based on AMEsim software,and the motor model,battery model,driver model,and vehicle dynamics model are built according to the above matching parameters.Then,two front and rear axle braking force distribution control strategies are proposed for the full-load and no-load states of the vehicle,which can effectively improve the braking stability of the vehicle by setting variable braking force distribution coefficients according to the braking intensity under the premise of meeting ECE braking regulations.Then the fuzzy controller is designed with the actual vehicle speed v,braking intensity z,and power battery SOC as the input and the braking force recovery proportional coefficient K as the output to reasonably allocate the rear axle mechanical braking force and electric braking force to improve the braking energy recovery rate of the whole vehicle.Finally,the braking energy recovery control strategy is modeled in Matlab/Simulink software,and a joint simulation platform is built with the vehicle model in AMEsim to simulate the original braking force distribution strategy under no-load conditions,the original braking force distribution strategy under full-load condition,the design strategy under no-load condition and the design strategy under full-load condition based on NEDC driving cycle conditions and CHTC driving cycle conditions.After comparing the simulation results,it is concluded that the braking energy recovery control strategy designed in this paper has a higher energy recovery rate.There are 52 figures,14 tables,65 references.