Research On Power System Modeling And Energy Management Strategy Of Electric-electric Hybrid Fuel Cell Bus

With the aggravation of global environmental pollution and the gradual shortage of oil energy supply,new energy methods are supplied in the automotive field to meet people’s needs.In the field of new energy vehicles,the pure electric vehicles are limited due to the cruising range and charging problems.Because of the pollution-free emissions,the endurance of traditional fuel vehicles and the cleanliness and efficiency of pure electric vehicles,the fuel cell hybrid vehicles are considered as the ideal vehicle development direction.Aiming at the modeling,simulation and energy management strategy of fuel cell bus,builds a simulation model of the fuel cell monomer,obtains its polarisation characteristic curve,and analyses the effects of temperature,proton film water content and gas partial pressure on the fuel cell performance;designs the fuel cell bus power system,builds models of the drive motor and power cell,and builds the power system of the fuel cell hybrid vehicle and The modeling and simulation of the rule-based ON/OFF control strategy and the power following control strategy were completed,and a comparative analysis of the two control strategies was carried out;with the objectives of optimizing hydrogen consumption and protecting the battery,an optimized dynamic planning optimization strategy based on the optimized power change rate was proposed,and a comparative analysis of the three strategies was carried out,and an optimized dynamic planning strategy with good economy was obtained..The specific research contents are as follows.1.The calculation model of the fuel cell is analyzed,and the simulation model of the fuel cell monomer is built in MATLAB/Simulink,and the reliability of the simulation model is verified by comparing with the theoretical polarization characteristic curve and experimental results.A comparative analysis of the simulation results at different temperatures,different proton film water content and gas partial pressure was completed,and the influence of the three factors on the fuel cell performance was analysed.2.According to the parameter index of the fuel cell bus,the vehicle parameters were calculated,the design of the power system of the fuel cell bus was completed,the drive motor selection and simulation model modelling were completed,and the theoretical analysis and simulation modelling of the power cell were carried out,and the MATLAB/Simulink software was used to establish the simulation model of the power system and the whole vehicle of the fuel cell hybrid vehicle.3.The ON/OFF control strategy and the power following control strategy of the fuel cell hybrid bus energy management strategy were analyzed,and the simulation models of the two strategies were built in MATLAB/Simulink respectively,and the simulation analysis of the two strategies under different initial cases of power cell SOC(State of Charge)was completed.The simulation results show that the power following strategy has better economy.4.Aiming at the problem that traditional dynamic planning does not consider the large power change rate of fuel cell and power cell when working under complex road conditions,which affects the life and efficiency of fuel cell and power cell,an optimised dynamic planning optimisation strategy based on optimised consideration of power change rate is proposed to enable fuel cell vehicles to meet the economy of hydrogen consumption while taking into account the durability of fuel cell and power cell.Through the simulation analysis of the three management strategies,it is verified that the optimized dynamic planning strategy has relatively smooth power variation of the fuel cell and SOC fluctuation of the power cell when the hydrogen consumption is minimized,which improves the durability of the fuel cell and the power cell.The research of the thesis provides a reliable reference for the design of fuel cell hybrid electric vehicles.