Direct optimal power extraction control for a tidal turbine system based on fuzzy power tuning

Abstract This paper focuses on the direct optimal power generation control for a horizontal-axis tidal turbine system by using fuzzy power tuning. The dynamics of this tidal turbine system is first described and modelled based on the modelling of individual components. The generator power is also be described from the power converter and DC-bus side. A fuzzy logic tuning method is then proposed to derive the optimal generator power by using the power converter current and its variations as input variables. The derived optimal generator power is used as the reference for direct power control by using cascaded control loops. The effectiveness of the proposed control has been verified based on a 50 kW tidal turbine system with gear ratio of 2 in MATLAB/Simulink simulations. The test results validate the proposed fuzzy tuning method is reasonable and the active generator power can be readily maximized while the reactive power is minimized by using the proposed direct optimal power control method.