Research On Control Strategy Of Brake Energy Recovery For 5.3m Pure Electric Logistics Vehicle

In recent years,the country's prospects for the industry have been generally optimistic due to the state's strong support for the pure electric vehicle industry and the introduction of many related subsidy policies.However,due to current battery technology,the driving range of the vehicle does not meet the needs of users.In a short period of time,the research on the battery technology of pure electric vehicles is difficult to make major breakthroughs,and most of them are concentrated in the laboratory test stage,and there is still a long way to go before the actual application In comparison,the brake energy recovery control strategy is another technical means to improve the endurance of pure electric vehicles,and the technology is more mature and more cost-effectiveThe so-called braking energy recovery control strategy of pure electric vehicle is to.reasonably allocate the ratio of mechanical friction braking force of front and rear wheels and regenerative braking force of motor in the total braking force on the premise of ensuring its safety and stability.This paper takes the 5.3-meter rear dr-ive electric logistics vehicle of Zhangzhou branch,Fujian province FORTA automobile industry co.,LTD as the research object.The purpose is to maximize the energy recovery of pure electric logistics vehicle without adding auxiliary devices.Aiming at the problem of how to allocate the proportion of braking force so as to recover more braking energy this paper proposes a control strategy of braking energy recovery system for pure electric logistics vehicle based on fuzzy controlThe core part of the control strategy is to develop the original braking energy recovery control strategy of ADVISOR,an advanced vehicle simulation software,and build related simulation models.According to the real situation,the relevant parameters of each model need to be set to improve the simulation accuracy.Based on the development environment of MATLAB/Simulink software,this paper designs a fuzzy controller and uses it to replace the table lookup method in ADVISOR to distribute the braking force.The fuzzy controller has three inputs,namely braking intensity Z,battery SOC(charge state),vehicle instantaneous speed V,and one output is the ratio K of the regenerative braking force to the total braking force of the vehicle.In order to verify the effectiveness of the braking energy recovery control strategy of pure electric logistics vehicle based on fuzzy control designed in this paper.The built braking energy recovery control strategy model is embedded in ADVISOR,and three typical cyclic conditions of European Highway CYC_ECE,American Highway CYC_UDDS and China Highway CYC_CHINA are selected for simulation research.The vehicle test and laboratory bench test were carried out on the research vehicle,and the vehicle controller of the test vehicle was tested with the ADVISOR default control strategy and the fuzzy control-based control strategy designed in this paper.The comparison verifies the practicability of the strategy designed in this paper.The.simulation and experimental results show that the braking energy recovery control strategy designed in this paper meets the expected requirements,and more braking energy is recovered than the ADVISOR's own control strategy,which improves the endurance of the pure electric logistics vehicle.