Parameter Matching Design And Optimization Of Power System For Pure Electric

Electric vehicle has the advantages of simplestructure,cleanness,environmental protection and energy saving,which can reasonably solve the problems are brought by the traditional automobile such as complicated structure,environmental pollution and energy shortage.Secondly,the pure electric vehicle is affected by the battery technology and the driving control technology,which brings some problems about the lack of driving distance and the lack of power and limit the widespread popularity.Therefore,In order to improve the efficiency of EV drive system and prolong EV endurance mileage,it is necessary to reasonable match of major part of the power system when vehicle running in various operating conditions.This paper is based on a pure electric vehicle research and development project of one domestic vehicle company,The focus of the work on the design of electric vehicle power system and transmission ratio optimization,The research work of pure electric vehicle is carried out.The target of the study is the vehicle's perforemance of power and economy,including the maximum gradient,acceleration time,maximum speed and electricity consumption per hundred kilometers.Meanwhile,many difficult problems be solved,Those problems were encountered in the process of electric vehicle research and development,such as,the establishment of the whole vehicle model and optimization model,the realization of the joint simulation,etc.The research method of this paper is the combination of theoretical basis,simulation calculation and experimental verification.Firstly,the classification and main features of key components such as motors and batteries are introduced,and the calculation method and theoretical basis including motor performance and fuel consumption and dynamic performance are analyzed.Secondly,this paper studies of the parameter design and selection of pivotal system parameters of the electric vehicle dynamic system,which includes drive motor and Power battery and transmission.Then,it uses the simple operation platform of the simulation software AVL CRUISE to establish a corresponding model.The model is used to simulate perforemance of the electric vehicle and simulation results are analyzed in the design.And the multi-objective genetic algorithm in ISIGHT software is used to optimize the speed ratio of the transmission system to improve the performance of the vehicle.Finally the complete vehicle performance test of power and economic is carried out.The test results verify the rationality and effectiveness of the research work.The results of this paper show that by improving the matching effect of a pure electric car power system,reduce the electric power consumption level,prolong EV endurance mileage,and improve the ability of research and development in the field of electric vehicle.On the basis of the original design scheme,after the speed ratio of transmission system is optimized.The simulation results show that the maximum speed is increased by 8.57%,and the endurance mileage by 1.2 km.