Journal of Zhejiang University SCIENCE A
ISSN 1673-565X(Print), 1862-1775(Online), Monthly

2007   Vol. 8   No. 9   p. 1505~1509

Nonlinear modelling of a SOFC stack by improved neural networks identification

WU Xiao-juan^†, ZHU Xin-jian, CAO Guang-yi, TU Heng-yong

(Institute of Fuel Cell, Shanghai Jiao Tong University, Shanghai 200030, China)
^†E-mail: xj_wu@sjtu.edu.cn
Received Dec. 22, 2006 revision accepted Apr. 13, 2007

Abstract: The solid oxide fuel cell (SOFC) is a nonlinear system that is hard to model by conventional methods. So far, most existing models are based on conversion laws, which are too complicated to be applied to design a control system. To facilitate a valid control strategy design, this paper tries to avoid the internal complexities and presents a modelling study of SOFC performance by using a radial basis function (RBF) neural network based on a genetic algorithm (GA). During the process of modelling, the GA aims to optimize the parameters of RBF neural networks and the optimum values are regarded as the initial values of the RBF neural network parameters. The validity and accuracy of modelling are tested by simulations, whose results reveal that it is feasible to establish the model of SOFC stack by using RBF neural networks identification based on the GA. Furthermore, it is possible to design an online controller of a SOFC stack based on this GA-RBF neural network identification model.

Key words: Solid oxide fuel cells (SOFCs), Radial basis function (RBF), Neural networks, Genetic algorithm (GA)
doi:10.1631/jzus.2007.A1505             CLC number: TK01

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