WAVE ENERGY HAS THE POTENTIAL TO PROVIDE A SUSTAINABLE SOLUTION FOR GLOBAL ENERGY DEMANDS, PARTICULARLY IN COASTAL REGIONS. THIS STUDY EXPLORES THE USE OF REINFORCEMENT LEARNING (RL), SPECIFICALLY THE Q-LEARNING ALGORITHM, TO OPTIMISE THE ENERGY EXTRACTION CAPABILITIES OF A WAVE ENERGY CONVERTER (WEC) USING A SINGLE-BODY POINT ABSORBER WITH RESISTIVE CONTROL. EXPERIMENTAL VALIDATION DEMONSTRATED THAT Q-LEARNING EFFECTIVELY OPTIMISES THE POWER TAKE-OFF (PTO) DAMPING COEFFICIENT, LEADING TO AN ENERGY OUTPUT THAT CLOSELY ALIGNS WITH THEORETICAL PREDICTIONS. THE STABILITY OBSERVED AFTER APPROXIMATELY 40 EPISODES HIGHLIGHTS THE CAPABILITY OF Q-LEARNING FOR REAL-TIME OPTIMISATION, EVEN UNDER IRREGULAR WAVE CONDITIONS. THE RESULTS ALSO SHOWED AN IMPROVEMENT IN EFFICIENCY OF 12% FOR THE THEORETICAL CASE AND 11.3% FOR THE EXPERIMENTAL CASE FROM THE INITIAL TO THE OPTIMISED STATE, UNDERSCORING THE EFFECTIVENESS OF THE RL STRATEGY. THE SIMPLICITY OF THE RESISTIVE CONTROL STRATEGY MAKES IT A VIABLE SOLUTION FOR PRACTICAL ENGINEERING APPLICATIONS, REDUCING THE COMPLEXITY AND COST OF DEPLOYMENT. THIS STUDY PROVIDES A SIGNIFICANT STEP TOWARDS BRIDGING THE GAP BETWEEN THE THEORETICAL MODELLING AND EXPERIMENTAL IMPLEMENTATION OF RL-BASED WEC SYSTEMS, CONTRIBUTING TO THE ADVANCEMENT OF SUSTAINABLE OCEAN ENERGY TECHNOLOGIES.

WAVE ENERGY HAS ENORMOUS POTENTIAL AND MANY GOOD QUALITIES, SUCH AS ITS PREDICTABILITY, ENERGY DENSITY AND LOW VARIABILITY. NEVERTHELESS, THIS TYPE OF ENERGY STILL NEEDS TO BE COMPETITIVE AGAINST OTHER TYPES OF RENEWABLE ENERGY, LIKE WIND OR SOLAR ONES. THIS IS MAINLY DUE TO ITS HIGH COST. ONE SOLUTION TO REDUCE THE COST OF WAVE ENERGY IS THE USE OF CONTROL STRATEGIES. IN THIS WORK, A SIMPLE POINT ABSORBER BASED ON THE DIMENSIONS OF AN ONGOING PROJECT, NAMED LAFKENEWEN, IS MODELED WITH LINEAR POTENTIAL THEORY AND THE SOFTWARE ANSYS-AQWA. THREE DIFFERENT CONTROL STRATEGIES, REACTIVE CONTROL, LATCHING CONTROL AND RESISTIVE CONTROL, ARE COMPARED FOR A REGULAR WAVE THAT REPRESENTS THE MEAN SEA STATE OF THE PROJECT SITE LOCATION. RESULTS SHOW THAT THE REACTIVE CONTROL CAN ACHIEVE UP TO 18 KW BUT FOR UNREALISTIC CONDITIONS. LATCHING CONTROL ALLOWS CONVERTING UP TO 4 KW SHOWING BETTER PERFORMANCE THAN THE RESISTIVE CONTROL, WHICH ONLY ALLOWS UP TO 0.8 KW AVERAGE.