Next Article in Journal
Trends in CO2 Emissions from China-Oriented International Marine Transportation Activities and Policy Implications
Next Article in Special Issue
Validating a Wave-to-Wire Model for a Wave Energy Converter—Part II: The Electrical System
Previous Article in Journal
Multi-Objective Scheduling Optimization Based on a Modified Non-Dominated Sorting Genetic Algorithm-II in Voltage Source Converter−Multi-Terminal High Voltage DC Grid-Connected Offshore Wind Farms with Battery Energy Storage Systems
Previous Article in Special Issue
Optimization of the Runner for Extremely Low Head Bidirectional Tidal Bulb Turbine
Article Menu
Issue 7 (July) cover image

Export Article

Open AccessArticle
Energies 2017, 10(7), 977; doi:10.3390/en10070977

Validating a Wave-to-Wire Model for a Wave Energy Converter—Part I: The Hydraulic Transmission System

1
Centre for Ocean Energy Research, Maynooth University, Maynooth, Co. Kildare, Ireland
2
Department of Mechanical Engineering, University of Bath, Claverton Down, Bath BA2 7AY, UK
*
Author to whom correspondence should be addressed.
Received: 24 May 2017 / Revised: 3 July 2017 / Accepted: 6 July 2017 / Published: 12 July 2017
(This article belongs to the Special Issue Marine Energy)
View Full-Text   |   Download PDF [11556 KB, uploaded 12 July 2017]   |  

Abstract

Considering the full dynamics of the different conversion stages from ocean waves to the electricity grid is essential to evaluate the realistic power flow in the drive train and design accurate model-based control formulations. The power take-off system for wave energy converters (WECs) is one of the essential parts of wave-to-wire (W2W) models, for which hydraulic transmissions are a robust solution and offer the flexibility to design specific drive-trains for specific energy absorption requirements of different WECs. The potential hydraulic drive train topologies can be classified into two main configuration groups (constant-pressure and variable-pressure configurations), each of which uses specific components and has a particular impact on the preceding and following stages of the drive train. The present paper describes the models for both configurations, including the main nonlinear dynamics, losses and constraints. Results from the mathematical model simulations are compared against experimental results obtained from two independent test rigs, which represent the two main configurations, and high-fidelity software. Special attention is paid to the impact of friction in the hydraulic cylinder and flow and torque losses in the hydraulic motor. Results demonstrate the effectiveness of the models in reproducing experimental results, capturing friction effects and showing similar losses. View Full-Text
Keywords: wave energy; wave-to-wire modelling; hydraulic transmission systems; Stribeck friction model; Schlösser model; experimental testing; validation wave energy; wave-to-wire modelling; hydraulic transmission systems; Stribeck friction model; Schlösser model; experimental testing; validation
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).

Share & Cite This Article

MDPI and ACS Style

Penalba, M.; Sell, N.P.; Hillis, A.J.; Ringwood, J.V. Validating a Wave-to-Wire Model for a Wave Energy Converter—Part I: The Hydraulic Transmission System. Energies 2017, 10, 977.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Energies EISSN 1996-1073 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top