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.

KEYWORDS:

• Black hole optimisation algorithm
• Interval Type-2 Fuzzy system
• Maximum power capture
• Point absorbers renewable energy
• Sea wave energy absorption
• Wave energy converter

Additional information

Notes on contributors

Mohammad Jalali

Mohammad Jalali is a PhD student in electrical engineering control. His major field of interest is generating maximum power from renewable energy sources. His undergraduate and graduate theses focused on extracting the maximum power from wind turbines using optimized methods. He has been following the field of wave energy and maximum power produced by Fuzzy control systems during his PhD studies since 2015. He has been working as a university lecturer and consultant in private and public institutions since 2010. Email: [email protected]

Reihaneh Kardehi Moghaddam

Reihaneh Kardehi Moghadam was born in 1979 in Mashhad, Iran. She studied medical engineering from 1997 to 2001 and graduated from Amirkabir University of Tehran. She got her master’s degree in electrical engineering from the Ferdowsi University of Mashhad in 2004, and she got her PhD degree in control engineering in 2010. She is an associate professor of Electrical engineering in Azad university of Mashhad. Her research interest includes: in optimal control, nonlinear control and wave energy converters.