Towards Ocean Grazer’s Modular Power Take-Off System Modeling:a Port-Hamiltonian Approach

Authors

J.J. Barradas-Berglind, M. Muñoz-Arias, Y. Wei, W.A. Prins, A.I. Vakis, B. Jayawardhana

Abstract

This paper presents a modular modeling framework for the Ocean Grazer’s Power Take-Off (PTO) system, which operates as an array of point-absorber type devices connected to a hydraulic system. The modeling is based on the port-Hamiltonian (PH) framework that enables energy-based analysis and control of the PTO system. Firstly, a modular model of a point-absorber hydraulic system, which represents the main building block of the PTO, is presented. The model consists of wave-mechanical and hydraulic subsystems that are interconnected with a transformer-type interconnection. Secondly, we show passivity of the point-absorber hydraulic element and the accumulation of potential energy, which is due to the novel pumping mechanism of the point-absorber. Finally, we illustrate these properties through simulation results.

Keywords

Wave energy; Ocean energy; Power take-off system; Point-absorbers; Passivity

Citation

• Journal: IFAC-PapersOnLine
• Year: 2017
• Volume: 50
• Issue: 1
• Pages: 15663–15669
• Publisher: Elsevier BV
• DOI: 10.1016/j.ifacol.2017.08.2397
• Note: 20th IFAC World Congress

BibTeX

@article{Barradas_Berglind_2017,
  title={{Towards Ocean Grazer’s Modular Power Take-Off System Modeling:a Port-Hamiltonian Approach}},
  volume={50},
  ISSN={2405-8963},
  DOI={10.1016/j.ifacol.2017.08.2397},
  number={1},
  journal={IFAC-PapersOnLine},
  publisher={Elsevier BV},
  author={Barradas-Berglind, J.J. and Muñoz-Arias, M. and Wei, Y. and Prins, W.A. and Vakis, A.I. and Jayawardhana, B.},
  year={2017},
  pages={15663--15669}
}

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