Research On Energy Management Strategy Of Fuel Cell Hybrid Electric Vehicles

Facing the severe environmental pollution and energy crisis in today's society,vigorously promoting the development of new energy vehicles has gradually become an effective way to alleviate the severe situation.Among them,fuel cell vehicles are based on their zero pollution,low energy consumption,strong battery life and high security,which has become a hot topic for countries to vigorously develop,and has a very broad development prospect.Fuel cell vehicles powered by multiple power sources can effectively improve the characteristics of slow dynamic response of pure fuel cells and the inability to collect excess energy.Fuel cell vehicles powered by fuel cells + batteries are jointly proposed to propose a reasonable energy management strategy to make full use of the energy provided by the fuel cell and the battery,so that the fuel cell as a main power source has a stable energy supply,while the battery as an auxiliary power source provides power within a certain SOC,and recover excess energy.Based on this goal,an improved energy management strategy based on fuzzy logic control is proposed.However,the design of fuzzy logic depends on the experience of experts,and there are certain errors and limitations.In this paper,an improved Multi-objective Cuckoo algorithm has optimized the energy management strategy.This algorithm has improved to a certain extent the shortcomings of the standard cuckoo algorithm and the lack of vitality.The fuzzy logic controlled energy management strategy takes the load required power Pload and the battery SOC as inputs,and formulates reasonable fuzzy logic controller rules and membership functions of input and output from three aspects of high SOC,medium SOC,and low SOC to obtain power.The distribution coefficient k,k is multiplied by the load required power Pload to obtain the power Pfc that the fuel cell needs to bear,and the remaining part is the power PBat that the battery needs to bear.The fuzzy logic control strategy optimized based on the improved multi-objective cuckoo algorithm is to optimize the membership function and control rules of the input and output of the fuzzy logic controller to a certain degree,and obtain a more appropriate power distribution coefficient k,which reduces the system hydrogen consumption,control battery SOC within 40%-80%.In the MATLAB / Simulink simulation environment,the overall simulation model of a fuel cell + battery hybrid fuel cell vehicle is built,and the paper is proposed less than two new European driving conditions and suburban cycling conditions.The control strategy is simulated and verified,and the power tracking control strategy is set as the control group.The superiority of the control strategyproposed in this paper is reflected by comparing the SOC level of the battery and the hydrogen consumption of the system.Simulation results show that the control method proposed in this paper has improved significantly in terms of fuel economy and endurance.When the initial SOC of the battery is high,the system's hydrogen consumption is reduced,and when the initial SOC is low,the battery's overdischarge is reduced,collecting excess energy,has corresponding advantages in actual operating conditions.