Laboratory Tests Assessment of a Mechanical Sensor-less MPPT Control Strategy for Tidal Turbines

The purpose of this study is to demonstrate through towing tank experiments the effectiveness of a novel mechanical sensor-less Maximum Power Point Tracking (MPPT) control for tidal stream turbines under fluctuations of the onset flow. The MPPT control method, based on the linear relationship between DC outputs of a Permanent Magnet Synchronous Generator (PMSG), was derived theoretically and validated through model tests. The tests were conducted under both steady-state and unsteady inflow conditions, using the 1.5 m diameter horizontal-axis device developed at the Queen’s University of Belfast. Results indicate that the proposed MPPT control strategy improves the convergence to the maximum power coefficient under regular wave conditions, thereby validat- ing its efficacy. A comparative analysis with a conventional Tip Speed Ratio (TSR) control method is also presented.