Experimental Performance Evaluation of a Hydraulic PTO System for ISWEC Wave Energy Converter

In this time of climate change and energy crisis, research into renewable energy is one of the focal points on which the whole world is focusing. Energy from the sea represents one of the most important undeveloped energy sources, so research in this direction is more important than ever these days. In this context, the ISWEC (Inertial System Wave Energy Converter) project developed by the Marine Offshore Renewable Energy Lab (MORE Energy Lab) in collaboration with the Politecnico di Torino (Italy) stands out as one of the most promising projects developed in Europe. As is well known in the literature, the Power Take-Off of marine energy conversion devices is the crucial point on which this technology is based. In fact, one of the main challenges in this field is the irregularity of the extracted torque, and the need for systems to regularise it is the main objective of this thesis. In [1] a new type of transmission has been developed to replace the mechanical transmission model used to this day in this type of device; it is a hydraulic transmission. In this context, a hardware-in-the-loop (HIL) test bench was developed at the Politecnico di Torino for the experimental evaluation of this new type of transmission. The subject of this thesis is the experimental evaluation of this test bench. Following the experimental campaign carried out in March 2022, a simulated model was created using the libraries of Simscape, a tool of Simulink - Matlab. By comparing the experimental data and the simulated model, through various steps described in detail, it was possible to validate the main components of the developed model. This work represents the first step of a path that will be developed in the future with the validation of the control system implemented, for now theoretically, to carry out a study of the efficiency of the power extracted from the entire ISWEC device. The thesis realised initially provides a description of the state of the art of PTO devices and a description of the choice made for the ISWEC Hydraulic PTO device, the description of the test bench constructed, the description of the experimental campaign carried out, the construction of the model simulated on Simscape, and finally the validation of this realised by comparing the experimental and simulated results. [1] Mauro Bonfanti, 2021, “Mixing the Power of Water and Oil - The Hydraulic PTO for Wave Energy Conversion”, Torino