Robust Hierarchical Control Strategy for Heaving Wave Energy Converters

Omsalama M. M. Saeed, Addy Wahyudie, Mohammed A. Jama

Abstract


Numerous reference-based control strategies have been developed for enhancing the captured and converted energy of the heaving wave energy converters (WECs). This study developed a hierarchical control strategy (HCS) that provided an optimal reference signal considering the different sea-states and constraints on the heaving buoy’s elevation. The developed HCS is composed of a higher hierarchical controller (HHC) and a lower hierarchical controller (LHC). An optimal reference signal, for different combinations of wave specific heights and frequencies under elevation’s constraints, is provided by the HHC. The buoy’s output velocity is regulated by the LHC, based on the reference signal provided by the HHC. Robustness and tracking performance are achieved by the LHC. The present paper utilized a proportional-integral-derivative (PID) controller augmented with sliding mode control (SMC), known for its robustness capabilities, for implementing the LHC. The developed control strategy was validated using regular (monochromatic) and irregular (polychromatic) sea-states. Validation process also considered both nominal and perturbed and disturbed systems. The HCS showed effectiveness in enhancing the power train of the heaving WECs while respecting the physical limitations of the system.

Keywords


Heaving Wave Energy Converters; Robust Control Strategy

Full Text:

PDF

References


J. Cruz, "Ocean Wave Energy, Current Status and Future Perpectives", Springer-Verlag Berlin Heidelberg, 2008. CrossRef

B. Drew, A. R. Plummer and M. N. Sahinkaya, "A review of wave energy converter technology," Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy, vol. 223, pp. 887-902, 2009. CrossRef

R. Alcorn and D. O' Sullivan, "Electrical Design for Ocean Wave and Tidal Energy Systems", London, United Kingdom: The Institution of Engineering and Technology, 2013.

A. Jaen, D. Andrade and A. Santana, "Increasing the effeciency of the passive loading strategy for wave energy conversion," Journal of Renewable and Sustainable Energy, vol. 5, p. 053132, 2013. CrossRef

M. Jama, A. Wahyudie, A. Assi and H. Noura, "An intelligent fuzzy logic controller for maximum power capture of point absorbers," Energies, vol. 7, pp. 4033-4053, 2014. CrossRef

M. Schoen, J. Hals and T. Moan, "Wave prediction and robust control of heaving wave energy devices for irregular waves," IEEE Transactions on Sustainable Energy, vol. 26, pp. 627-638, 2011. CrossRef

G. Li and M. Belmont, "Model predictive control of sea wave energy converters part ii: The case of an array of devices," Renewable Energy, vol. 68, pp. 540-549, 2014. CrossRef

M. Richter, M. Magana, O. Sawodny and T. Brekken, "Nonlinear model predictive control of a point absorber wave energy converter," IEEE Transactions on Sustainable Energy, vol. 4, pp. 118-126, 2013. CrossRef

J. Falnes, "Ocean Waves and Oscillating Systems", Cambridge University Press, 2002. CrossRef

M. Jama, H. Noura, A. Wahyudie and A. Assi, "Enhancing the performance of heaving wave energy converters using model-free control approach," Renewable Energy, vol. 83, pp. 931-941, 2015. CrossRef

F. Fusco and J. Ringwood, "A simple and effective real-time controller for wave energy converters," IEEE Transactions on Sustainable Energy, vol. 4, pp. 21-30, 2014. CrossRef

F. Fusco and J. Ringwood, "Hierarchical robust control of oscillating wave energy converters with uncertain dynamic," IEEE Transactions on Sustainable Energy, vol. 5, pp. 598-966, 2014. CrossRef

T. Brekken, "On model predictive control for a point absorber wave energy 174 converter," in IEEE Trondheim PowerTech, Trondheim, Norway, 2011.

A. Wahyudie, M. A. Jama, O. Saeed, H. Noura, A. Assi and K. Harib, "Robust and low computational cost controller for improving captured power in heaving wave energy converters," Renewable Energy, vol. 82, pp. 114-124, 2015. CrossRef

O. Danielsson, "Wave energy conversion: Linear synchronous permanent magnet generator," Ph.D. dissertation, Uppsala University, 2006.

R. Taghipoura, T. Pereza and T. Moan, "Hybrid frequency-time domain models for dynamic response analysis of marine structurres," Ocean Engineering, vol. 35, pp. 685-705, 2008. CrossRef

W. Cummins, "The impulse response functions and ship motions," Schiff-stechnik, vol. 9, p. 101, 1961.

G. D. Backer, "Hydrodynamic design optimization of wave energy converters consisting of heaving point absorbers," Ph.D. dissertation, University of Ghent, 2010.

M. Eriksson, "Modelling and experimental verification of direct drive wave energy conversion," Ph.D. dissertation, Uppsala University, 2007.

Z. Ballard and B. Mann, "Two-dimenssional nonlinear analysis of an untethered spherical buoy due to wave loading," Journal of Computational and Nonlinear Dynamics, vol. 8, pp. 041019(1)-041019(2), 2013.

C. Canudas, H. Olsson, K. Astrom and P. Lischinsky, "A new model for control of systems with friction," IEEE Transactions on Automatic Control, vol. 40, pp. 419-425, 1995. CrossRef

W. Xie, "Sliding-mode-observer-based adaptive control for servo actuator with friction," IEEE Transactions on Industrial Electronics, vol. 54, pp. 1517-1527, 2007. CrossRef

M. Leijon, O. Danielsson, M. Eriksson, K. Thorburn, H. Bernhoff, J. Isberg, J. Sundberg, I. Ivanova, E. Sjostedt, O. Agren, K. Karlsson and A. Wolfbrandt, "An electrical approach to wave energy conversion," Renewable Energy, vol. 31, pp. 1309-1319, 2006. CrossRef

J. E. Slotine and W. Li, Applied Nonlinear Control, Prentice Hall, 1991.

J. Falnes, "A review of wave-energy extraction," Renewable Energy, vol. 20, pp. 185-201, 2007. CrossRef

J. Hals, J. Falnes and T. Moan, "Constrained optimal control of a heaving buoy wave-energy converter," Journal of Offshore Mechanics Arctic Eng., vol. 133, p. 011401, 2010. CrossRef

X. S. Yang, Engineering Optimization: An Introduction with Metaheuristic Applications, John Wiley and Sons, 2010. CrossRef

A. Santana, A. Jaen and D. Andrade, "Maximizing output power of linear generators for wave energy conversion," International Transactions on Electrical Energy Systems, vol. 24, p. 875890, 2014.

M. Jama, "Control strategies for improving the performance of heaving wave energy converters," Ph.D. dissertation, United Arab Emirates University, 2015.

K. Nielsen and T. Pontes, "Ocean energy systems’ report: Annex ii task 1.1 generic and site related wave energy data," March 2010. [Online]. VIEW

M. Jama, A. Wahyudie, A. Assi and H. Noura, "Controlling heaving wave energy converter using function-based model predictive control technique," Control and Decision Conference (CCDC), pp. 2705-2710, 2013. CrossRef




DOI: http://dx.doi.org/10.21535%2Fijrm.v2i3.871

Refbacks

  • There are currently no refbacks.




Creative Commons License
This work is licensed under a Creative Commons Attribution 3.0 License.