TY  - Journal Article
AU  - Antolín-Urbaneja, Juan Carlos
AU  - Cortes, A.
AU  - Marcos, Marga
AU  - Lasa, Joseba
AU  - Estensoro, Patxi
AU  - Cabanes, Itziar
TI  - Assembled PTO based on an array of double-acting hydraulic cylinders for WECs: From Conceptual Design to an Adjusted Detailed Model
PY  - 2015
PB  - Bilbao Marine Energy Week
AB  - All Wave Energy Converters (WECs) based on wave activated bodies comprises a Power Take-
Off (PTO) system among other subsystems like the reaction mechanism, the supervisor of the
system and the electrical generator. One of the most applied PTO systems consists of oil high
pressure hydraulic devices. These devices are able to apply high forces, to store large
quantities of energy through accumulators and to provide smoother power output to the motor
coupled to a generator. In these systems the poor efficiency and the oil leakages contaminating
the environment are considered main drawbacks. Despite of this, they are widely used in
several promising WECs with the aim of optimizing the harvested wave energy along the time.
The initial challenge to absorb an oscillating movement of ±30º at 5rad/s as a maximum angular
speed absorbing up to 16000Nm from a specific WEC, led to the development of a simplified
hydraulic model before manufacturing a PTO prototype to be verified in a Test Bench (Figure 1).
The experimental results of PTO under different conditions have been used to adjust a full
detailed PTO Model using Mathworks® software platform.
This work presents a patented oil high pressure hydraulic PTO prototype based on an array of
four double-acting hydraulic cylinders. This prototype has been designed and completely
modelled as a proof concept at 1:4 scale being able to apply a variable Coulomb type damping
torque through the activation of each hydraulic cylinder independently and through the
modification of geometrical parameters easily. The complete model of the PTO has been
accurately tuned up through adjustment of model parameters using the results of the
experimental tests. This will allow the study of control strategies to optimize the extracted wave
energy from a specific WEC, like point-absorbers.
UR  - http://hdl.handle.net/11556/129
ER  -