Identification of fractional-order models for condition monitoring of solid-oxide fuel cell systems

Boštjan Dolenc*, Gjorgji Nusev, Ðani Juricic, Vanja Subotic, Christoph Hochenauer, Pavle Boškoski

*Corresponding author for this work

Research output: Contribution to journalConference articlepeer-review


With rising market deployment the condition monitoring of solid oxide fuel cell systems is gaining particular importance. The conventional approaches mainly use electrochemical impedance spectroscopy based on the repeated sinusoidal perturbation over a range of frequencies. One of the notable weaknesses of the approach is excessively long perturbation time needed to properly evaluate the impedance curve. In this paper, we propose a time-efficient approach in which, a short, persistently exciting and small-amplitude perturbation is used to excite all the relevant system eigenmodes. A model structure from a class of linear fractional order models is selected to describe the perturbed dynamics and to account for anomalous diffusion processes in the cells. Then, the model parameters are estimated directly from measured input and output records. The paper presents a computationally efficient parameter estimation procedure in which the numerical issues of differentiation of noisy signals are alleviated by using modulating functions. In practice, that means a combination of filtering and application of conventional least squares. The approach is applied on a case of health assessment of solid oxide fuel cells.

Original languageEnglish
Pages (from-to)12014-12019
Number of pages6
Issue number2
Publication statusPublished - 2020
Event21st IFAC World Congress 2020 - Berlin, Germany
Duration: 12 Jul 202017 Jul 2020


  • Condition monitoring
  • Fractional order systems
  • Solid oxide fuel cell systems
  • Time-domain identification

ASJC Scopus subject areas

  • Control and Systems Engineering

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