Study On Hybrid Power System Design Of Fuel Cell Electric Vehicle

With the restriction of the supply of traditional fossil fuels and the escalation of environmental protection pressure,new energy vehicles have emerged.Unlike pure electric vehicles,which use a single power battery as their energy supply,fuel-cell cars typically use a mix of fuel cells and power cells.Because of the advantages of fuel cell in energy storage mass density and energy conversion efficiency,fuel vehicle has the advantages of light weight and high efficiency,China's fuel cell vehicle research and development is still in the initial stage,this thesis mainly studies the configuration optimization,modeling and simulation,energy management strategy and controller design of fuel cell vehicle and hybrid powertrain.Firstly,a configuration optimization method is proposed to optimize the cost and weight of fuel cell hybrid powertrain and to satisfy the performance constraints of the fuel cell vehicle.The multi-objective particle swarm optimization algorithm is used to solve the proposed optimization problem,and the objective function Pareto frontier is obtained.Secondly,starting from the top-level model architecture of the system,the fuel cell mechanism model,the power battery equivalent circuit model and the DC/DC converter fitting efficiency model are successively established.Thirdly,an energy management strategy based on improved stochastic dynamic programming was designed and compared with the energy management strategy based on determined rules under ADVISOR simulation platform.The results showed that the strategy of improved stochastic dynamic programming could improve the power generation efficiency of fuel cell and extend the driving range of fuel cell vehicles.Then,system controller based on automotive microprocessor S32K144 was developed,the fuel cell power generation system platform and electric-electric hybrid power system platform were built,and the optimal condition control test of fuel cell system and power output control test of hybrid power system were also carried out.The results show that the controller can control hydrogen pressure,air pressure,system temperature and energy flow well.