Comparative assessment of control strategies for the biradial turbine in the Mutriku OWC plant

To be competitive against other renewable energy sources, energy converted from the ocean waves needs to reduce its associated levelised cost of energy. It has been proven that advanced control algorithms can increase power production and device reliability. They act throughout the power conversion chain, from the hydrodynamics of wave absorption to the power take-off to improve the energy yield. The present work highlights the development and test of several algorithms to control the biradial turbine which is to be installed in the Mutriku oscillating water column plant. A collection of adaptive and predictive controllers is explored and both turbine speed controllers and latching strategies are examined. A Wave-to-Wire model of one chamber of the plant is detailed and simulation results of six control laws are obtained. The controllers are then validated using an electrical test infrastructure to prepare the future deployment in the plant. Finally, the control strategies are assessed against criteria like energy production, power quality or reliability.This work has received funding from the European Union'sHorizon 2020 research and innovation programme under grantagreement No 654444 (OPERA Project). This work was financed by GV/EJ (Basque Country Government) under grants IT1324-19. The second author was partially funded by the Portuguese Foundationfor Science and Technology (FCT) through IDMEC, under LAETAPEst-OE/EME/LA0022 by FCT researcher grant No. IF/01457/2014.The authors acknowledge AZTI Tecnalia for wave resource data measured at the plant