Research On Operation Optimization For Range Extended Electric Vehicle

Although the development of modern industrial technology brings a lot of convenience to people,s life,at the same time,it leads to the rapid consumption of petroleum resources and the global atmospheric pollution.This phenomenon has seriously hindered the further development of human society.As an important representative of modern industrial technology,drastic changes are taking place in the automotive industry.Electric vehicles,hybrid vehicles,and fuel cell vehicles,as the representatives of new energy,have gradually become a research hotspots in the automotive field.Range extended electric vehicle(REEV)as a special kind of hybrid electric vehicle,its main energy source is composed of the power battery and the auxiliary power unit system.It can not only realize the drive under the pure electric mode in the short distance,but it can also be used to start the system to provide energy for the operation of the whole vehicle and realize the long-distance driving when the power battery energy is not enough.It is one of the most important new energy vehicle accord to Chinese reality in the history of which change from traditional electric vehicles to pure electric vehicles and fuel cell vehicles.Focused on the economic performance and emission performance of the REEV,the operation optimization of the REEV are researched in this paper.The main work and innovations are as follows:1.The basic dynamic system structure of several different types of hybrid electric vehicles are analyzed respectively.The working state of the REEV is deeply researched.Further more,the problems and the difficulties of the REEV operation optimization are confirmed.2.The fuel consumption rate of the REEV is researched in the paper.Firstly,combining with the actual working condition of the auxiliary power unit(APU)and the constraint conditions of speed and torque of three working patterns like global optimization,optimization on the specific power point,optimization on the specific power range,we build a particle swarm optimization model(PSOM)for the APU fuel consumption.Then,experiments are carried out in the three working modes and get the curve of brake specific fuel consumption(BSFC).The experiment results show that the proposed approach can effectively reduce the fuel consumption of the APU and improve the vehicle fuel economy.3.The operation optimization of range extender in electric vehicle is researched.Firstly,considering the fuel consumption,CO and NOx emissions,the comprehensive model is established by the weighted method and two kinds of common conditions are presented.Secondly,the shortage of standard PSO algorithm is indicated,and the improved PSO algorithm is proposed.The distribution of the improved PSO optimal solution is funded out.Compared with standard PSO algorithm,it is demonstrated that the improved PSO can effectively avoid falling into local optimal solution.Finally,the curve of best composite cost curve under the condition of different weights is gotten.It is verified that the proposed approach can realize the operation optimization of electric vehicle under different operating conditions by adjusting the weights.4.The GUI for fuel consumption rate optimization of the REEV is established.The user can set the parameters of PSO algorithm in this GUI,and select different optimized output model to achieve optimization,which is useful to the popularization and application of the article.In the last part of this paper,the research work is summarized and the further research directions of the author are prospected.