An Optimal Interval Type-2 Fuzzy Logic Controller for Maximum Power Capture of Point Absorbers

Abstract

An optimal interval Type-2 Fuzzy logic controller is proposed for maximum power capture from point absorbers. First, based on an introduced point absorber, a model-based feedback-simplifier is proposed to reduce the complexity of the nonlinear part of the model. Then, two interval Type-2 Fuzzy systems are designed for finding the optimal values of damping and stiffness coefficients so that the maximum power absorption is realised. A black hole optimisation algorithm is then introduced to find the optimal values of the parameters of the Fuzzy system. Finally, the high performance of the proposed scheme is confirmed using simulations. The contributions of this paper are: (1) designing a model-based feedback simplifier for point absorbers, (2) introducing a state space of the final closed-loop system, (3) designing an interval Type-2 Fuzzy controller for the final system, (4) training the Fuzzy controller parameters using a black hole optimisation algorithm.