Research On Energy Management Strategy Of Fuel Cell Vehicle Based On Degradation Model

Currently,human society is facing serious environmental pollution and energy shortage problems,and finding clean and sustainable energy is a current research hotspot.The transportation industry is one of the key industries in the energy reform.Among them,hydrogen fuel cell vehicles have received extensive attention due to their clean,sustainable,and long-lasting characteristics.Proton exchange membrane fuel cell is one of the most widely used in automobiles.It has the characteristics of high specific power,fast start-up,and low operating temperature.Adding auxiliary energy sources to fuel cell vehicles can provide extra energy to satisfy vehicle driving during high-power conditions on the one hand,and on the other hand,it can recover the feedback energy when the vehicle is braking.The fuel cell hybrid vehicle studied in this paper uses proton exchange membrane fuel cells as the main energy source,and lithium batteries as the power system structure of the auxiliary energy storage system.Studies have shown that the main factors restricting the development of fuel cell vehicles are cost and life span,while the biggest factor affecting the life span of vehicle fuel cells is the frequent variable load conditions of the vehicle.This article fully considers the life of fuel cells,and develops a reasonable energy management system based on Pontryagin’s minimum value.The main work done are:(1)Comparative analysis of various components in the fuel cell vehicle power system to determine the research object of this article.The fuel cell,auxiliary energy storage system and DC/DC converter are selected,the power system of different structures is compared and analyzed,and the power system structure in this paper is determined to be the fuel cell structure of fuel cell + lithium battery.Establish a mathematical model for fuel cell vehicles to provide theoretical support for the vehicle simulation model after applying the energy management system.(2)Study the principle of minimum value,apply it to the energy management system of fuel cell vehicles,and establish a mathematical model for it.In order to prove the rationality of the principle of minimum value,the power follow-up energy management strategy is cited,and the vehicle fuel consumption and battery SOC are simulated and analyzed based on Matlab/simulink.Improve the principle of minimum value to control the value of co-state variables and make them change in real time.When the value of the battery SOC is larger or smaller,it can be brought to a reasonable value as soon as possible,so that the battery can work in a reasonable working range.(3)Research the influencing factors that affect the life of fuel cells,and formulate energy management strategies to avoid vehicles working under conditions that seriously affect the life of fuel cells as much as possible.The output power of the fuel cell is restricted to make it work smoothly and prolong its life.(4)Considering the impact of system degradation on fuel cell vehicles,fuel cells and batteries have a decay voltage during use.Considering the degradation model in the energy management strategy is conducive to reasonable control of the power system and can be more accurately estimated.Driving mileage.