Study On Power System Design And Energy Management Strategy Of ISG Hybrid Eletric Bus

Based on the enterprise "ISG 2 hybrid power system" project,taking ISG hybrid power system as the research object,I have completed the design of its power system plan,including the matching and selection of key parts of power system and the optimization design of energy management strategy,and the test was carried out..The specific research contents are as follows::Firstly,combined with the characteristics of urban public transport and the power demand of typical urban cycle conditions in China,the design goal of the whole vehicle system scheme is put forward.Through the analysis of the configuration and working mode of ISG hybrid power system,the design principle and minimum requirements of the key components of powertrain system are obtained.On this basis,detailed calculation and matching of key parts are carried out.According to the existing suppliers' products,the selection of key parts and components was carried out.Secondly,using Matlab simulation platform,through experimental method and theoretical method,for modeling of key components,including engine,motor,battery,vehicle model,driver model and so on.Thirdly,in order to obtain an excellent energy management strategy which can be applied in engineering,a fuzzy energy management strategy of hybrid electric bus based on DP optimization is established.According to the driving characteristics of passenger cars,the input and output variables are selected.By discretization of the given cycle of typical cities in China,gridding variables,adding constraint function,the reachable state set and the admissible control set are setted up.The multi objective cost function with clutch and engine start-stop factors is established.On the basis of Matlab/Simulink platform,through the dynamic programming algorithm,the theoretical optimization of the bus working mode distribution under the different SOC initial values and the engine working point distribution are getting,based on the CTDCBC working condition.As a reference,extracting the design parameters,the fuzzy controller of the hybrid electric bus is established.Finally,in the Matlab/Simulink,the simulation of typical cities in China is carried out,and the simulation results are obtained to meet the vehicle dynamic and economic design requirements,to illustrate the correctness of the vehicle system designed by this paper.Taking "Fugong" 12 m test vehicle as the refit object,the real road test was carried out in Xiamen 324 National highway.The whole vehicle performance test results are similar to the simulation results,and the error range is very small,which belongs to the normal phenomenon.The test results show that the whole vehicle power system has good dynamic performance and economic performance,which meets the initial design requirements,and further proves the reliability and correctness of the hybrid power system designed in this paper.