The Reserch Of Circuit System Modeling And Design Based On Direct Methanol Fuel Cell

Nowadays,with the rapid development of information technology and the depletion of fossil energy,new energy technology has been paid more and more attention.Direct methanol fuel cell(DMFC)has become the research focus of new energy technology because of its high energy density,clean and environmental protection,high energy conversion efficiency,easy operation and miniaturization.Due to the influence of many factors,the output performance of the DMFC is far from its theoretical value.It is necessary to analyze the reaction phenomena of the DMFC and provide optimization solutions.Based on the basic principle of direct methanol fuel cell,the mathematical model and physical model of passive DMFC were established.The phenomena of mass transfer,heat transfer and electrochemical reaction of passive DMFC were analyzed by mathematical model and physical model.According to the physicochemical principles of mass transfer,heat transfer and electric reaction of the DMFC,the circuit system model of passive DMFC was built by using the logic operation characteristics of the circuit.The circuit system model coupled with five modules:anode heat transfer,cathode heat transfer,ohmic loss,anode overpotential and cathode overpotential.The effect of ambient temperature on the reaction parameters of the DMFC was considered.Then,based on the analysis of mathematical model,physical model and circuit system model,two schemes were proposed to optimize the performance of DMFC through temperature.One is to use silica gel heating pad and temperature control to optimize DMFC,the other is to use particle swarm optimization algorithm to find the optimal layout.In the first scheme,a DMFC was designed and manufactured,and its output performance was tested and analyzed at different temperatures and concentrations.In the second scheme,the program of particle swarm optimization to find the optimal coordinates of DMFCs was compiled,and the COMSOL simulation software was used to verify the accuracy of the layout.The experimental results show that the output results of the circuit system model and the mathematical model of the direct methanol fuel cell are in agreement with each other,and accord with the output characteristics of the DMFC.The scheme of silica gel heating pad combined with temperature control can improve the temperature of the DMFC,reduce flooding and improve the output performance of the DMFC.Particle swarm optimization(PSO)algorithm found better layout coordinates of DMFCs,and the accuracy of DMFCs layout was proved by COMSOL simulation software,which shows that this scheme can improve the temperature of DMFC without peripheral equipment,and then improve the output power density of the DMFC and DMFC stack.