Model-based design and optimization of a dielectric elastomer power take-off for oscillating wave surge energy converters

This paper investigates a new kind of device for producing electricity from the mechanical energy carried by ocean waves. The proposed machine, named poly-surge, is based on an existing sea-bottom hinged surging-flap concept that is equipped with a new power take-off (PTO) system based on a novel soft dielectric elastomer (DE) transducer. DEs are highly deformable polymeric materials that can be used to conceive electrostatic generators relying on capacitance variation. This kind of generators shows a number of features that well match the requirements of a wave energy converter since they are light-weight, low-cost, tolerant to salty/aggressive marine environment, noise-free during operation, and easy to manufacture and install. The considered poly-surge converter employs a parallelogram-shaped DE generator (PS-DEG) arranged in a dual agonist–antagonist configuration, which makes it possible to provide the flap with controllable bidirectional torques. In this paper, first a complete wave-to-wire multiphysics model of the overall system is described that assumes a simplified hydrodynamic response for the hinged-flap and an electro-hyperelastic behaviour of the PS-DEG. Second, a procedure is presented for the dimensioning and optimization of the PS-DEG for given sets of poly-surge flap dimensions, wave-climate information and constraints on both design and operational variables. Finally, simulation results are provided to demonstrate that the poly-surge can achieve quasi-optimal power production with a properly designed agonist–antagonist DEG PTO system.

[1]  A. Ibrahimbegovic.  Nonlinear Solid Mechanics , 2009 .

[2]  Ron Pelrine,et al.  Dielectric elastomers: generator mode fundamentals and applications , 2001, SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring.

[3]  Matthew Folley,et al.  The oscillating wave surge converter , 2004 .

[4]  Rocco Vertechy,et al.  Modeling of an Oscillating Wave Surge Converter With Dielectric Elastomer Power Take-Off , 2014 .

[5]  Paul Steinmann,et al.  Hyperelastic models for rubber-like materials: consistent tangent operators and suitability for Treloar’s data , 2012 .

[6]  Marco Fontana,et al.  DYNAMIC MODEL OF DIELECTRIC ELASTOMER DIAPHRAGM GENERATORS FOR OSCILLATING WATER COLUMN WAVE ENERGY CONVERTERS , 2013 .

[7]  Aurélien Babarit,et al.  Hydro-elastic modelling of an electro-active wave energy converter , 2013 .

[8]  Ron Pelrine,et al.  Innovative power generators for energy harvesting using electroactive polymer artificial muscles , 2008, SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring.

[9]  Guillaume Ardoise,et al.  Standing wave tube electro active polymer wave energy converter , 2012, Smart Structures.

[10]  H. Eidsmoen.  Optimum Control of a Floating Wave-Energy Converter With Restricted Amplitude , 1996 .

[11]  J. Falnes.  Ocean Waves and Oscillating Systems , 2002 .

[12]  Helen C.M. Smith,et al.  Protocols for the Equitable Assessment of Marine Energy Converters , 2011 .

[13]  Torgeir Moan,et al.  Corrigendum to “Numerical benchmarking study of a selection of wave energy converters” [Renew Energy 41 (2012) 44–63] , 2015 .

[14]  S. Salter.  Wave power , 1974, Nature.

[15]  Noureddine Benseddiq,et al.  A fracture criterion of rubber-like materials under plane stress conditions , 2006 .

[16]  Rocco Vertechy,et al.  Parallelogram-shaped dielectric elastomer generators: Analytical model and experimental validation , 2015 .

[17]  T. Moan,et al.  Constrained Optimal Control of a Heaving Buoy Wave-Energy Converter , 2011 .

[18]  Trevor Whittaker,et al.  Analysis of the nearshore wave energy resource , 2009 .

[19]  M. N. Sahinkaya,et al.  A review of wave energy converter technology , 2009 .

[20]  António F.O. Falcão,et al.  Wave energy utilization: A review of the technologies , 2010 .

[21]  Benedikt Scherber,et al.  Electroactive polymers for gaining sea power , 2013, Smart Structures.

[22]  Zhigang Suo,et al.  Dielectric Elastomer Generators: How Much Energy Can Be Converted? , 2011, IEEE/ASME Transactions on Mechatronics.

[23]  Matthew Folley,et al.  The design of small seabed-mounted bottom-hinged wave energy converters , 2007 .

[24]  D. Rossi,et al.  Dielectric elastomers as electromechanical transducers: Fundamentals, Materials, Devices, Models and Applications of an Emerging Electroactive Polymer Technology , 2008 .

[25]  T. Whittaker,et al.  Nearshore oscillating wave surge converters and the development of Oyster , 2012, Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences.

[26]  Rocco Vertechy,et al.  Modeling of a heaving buoy wave energy converter with stacked dielectric elastomer generator , 2014 .

[27]  Tristan Perez,et al.  Time- vs. frequency-domain identification of parametric radiation force models for marine structures at zero speed , 2008 .

[28]  Johannes Falnes,et al.  A REVIEW OF WAVE-ENERGY EXTRACTION , 2007 .

[29]  Aurélien Babarit,et al.  Numerical benchmarking study of a selection of wave energy converters , 2012 .