Modeling for electrical characteristics of solid oxide fuel cell based on fractional calculus

Abstract

It's vital for the research of electrochemical reaction in solid oxide fuel cell (SOFC) to establish accurate dynamic model of its electrical characteristics. The inherent potential polarization of SOFC is analyzed, and integer order dynamic model is established by equivalent circuit. Experimental data is studied by electrochemical impedance spectroscopy (EIS), and its novel fractional order dynamic model is proposed exploringly based on the capacitor theory. Then, the parameters of integer order and fractional order models are optimized by genetic algorithm. Finally, according to the comparison of integer order dynamic model, fractional order dynamic model and impedance spectra of experimental data, the conclusion can be obtained that electric double- layer in electrode/electrolyte interface have non-integer order characteristics, and potential polarization of SOFC is more suitable to be characterized via fractional order dynamic model.