The effects of sea-state on optimal generator parameters for a wave energy converter

Paper in proceeding, 2024

The power take-off (PTO) system and control laws for wave energy converters (WECs) are crucial for system performance. Determining optimal PTO parameters based on different sea states is key for formulating control laws, identifying optimal WEC locations, and optimizing wave-to-wire performance. This study focuses on an oscillating water column (OWC) type WEC developed by Waves4Power using a buoy and piston in a water tube to generate hydraulic pressure in an accumulator tank for an electric generator. For 78 different sea states, optimal generator parameters maximizing electrical output are identified using waves simulated from Pierson-Moskowitz (PM) spectra and a Simulink model, including non-linear PTO effects. Results show a strong dependency between optimal generator speed and sea state, suggesting control laws based on sea state can enhance energy production. Wave steepness is the most important characteristic, hence four representative sea states based on their steepness are used to illustrate results.