Energy Management Predictive Control Of FCHEV Considering Fuel Cell Decay

It is difficult to achieve a breakthrough in energy saving and emission reduction of traditional internal combustion engine vehicles.In contrast,the new energy vehicles more environmentally friendly,and low fuel consumption,is an important direction for future car development.The fuel cell vehicle can provide the environmental benefits of the battery electric vehicle,and the driving range is longer,and the hydrogenation time is short.However,the durability of fuel cells has become a major problem in the current fuel cell vehicle industry.In order to improve the economic performance of fuel cell vehicles and ensure the durability of fuel cell system,in this paper,the energy management strategy of plug in fuel cell vehicle is designed based on the decay rate of fuel cell system.The main contributions are summarized as follows:(1)Analysis of fuel cell vehicles different hybrid drive mode,choose hybrid drive mode for fuel cell system and power battery.Based on the basic parameters and performance indexes of the drive system,the parameters of the drive motor,power battery,fuel cell system and transmission system are designed.(2)The simulation model of fuel cell vehicle is established,including fuel cell system model,DC/DC model and power battery model.The energy management control structure of inner and outer layers is designed,which includes the optimization of the power output of the inner layer of the power battery,and the optimization of the output power of the fuel cell system with the feedback of the voltage decay rate of the fuel cell system.The vehicle simulation model is built by Matlab/Simulink,and the effectiveness of the vehicle model is verified by the simulation of the drive cycle,which lays the foundation for the further optimization of the energy management strategy.(3)The energy management module inner control uses ECMS to optimize the target power of the power battery.The effectiveness of the designed ECMS strategy is verified by simulation and comparison with the rule based optimization strategy.On the basis of the ECMS strategy,the optimal output power of the fuel cell system is analyzed by the feedback control of the output voltage decay rate of the fuel cell system.The results show that,compared with the fixed power constraints,the feedback control can optimize the vehicle economic performance and the voltage decay rate of the fuel cell system.(4)When know the driving range,design ECMS strategy based on mileage optimization,keep charge-depleting mode at the full mileage.The simulation results show that compared with the traditional CD-CS strategy,the vehicle economy can be further improved.When the mileage is unknown,design of ECMS strategy based on condition prediction,according to Markov Monte Carlo predicted the future demand driven motor power.Through the dynamic programming,the ECMS strategy can realize the equivalent hydrogen consumption of the vehicle in the prediction time domain to achieve the local optimization,compared with the ECMS simulation results,the fuel cell vehicle economy is improved.(5)In order to solve the adaptability of energy management strategy to the long and steep working conditions,design of long uphill energy management optimization based on slope prediction.Prediction of long uphill ahead by vehicle navigation system.By limiting the discharge of the power battery in advance,the SOC of the power battery is in a reasonable range.Thereby ensuring the health of the power battery without sacrificing the durability of the fuel cell system.