Integral Sliding Mode Control of DFIG-Based OWC Systems with Fuzzy Logic MPPT Under Realistic Wave Energy Conditions

This paper presents an advanced control strategy for Oscillating Water Column (OWC) systems based on Doubly Fed Induction Generators (DFIGs), designed to operate under realistic and variable wave energy conditions. The primary goal is to improve system reliability and energy conversion efficiency in spite of the nonlinear and time-varying characteristics of ocean waves. This is accomplished by developing an Integral Sliding Mode Control (ISMC) to control the DFIG currents, guaranteeing resilience to external shocks and uncertainties. To optimize the collected wave power and dynamically adjust the operating point, a Maximum Power Point Tracking (MPPT) method based on fuzzy logic is used in parallel. In-depth simulations are conducted under fluctuating wave conditions, and a thorough mathematical model of the OWC–DFIG system is developed. The findings show that, in comparison to traditional control systems, the suggested ISMC–Fuzzy MPPT scheme greatly increases grid compatibility, maximizes energy extraction, and improves power output stability. Additionally, the suggested framework ensures smoother operation in challenging marine conditions by providing faster dynamic response and less oscillations at the maximum power point. The limitations of conventional linear controllers are addressed by the combination of ISMC and fuzzy logic, which offers a balance between robustness and adaptability. For large-scale renewable integration, this work thus marks a step toward more robust and effective wave energy conversion systems. These results support the suggested strategy’s ability to develop wave energy conversion technologies and support the integration of sustainable renewable energy sources.