Abstract
This paper introduces a novel wave energy converter design that utilizes a concept for regulating displacement amplitude with an internal non-linear rotative gravity pendulum system. A standard wave energy converter, which operates as a cylindrical buoy floating in an ocean of finite depth and is tethered to a concrete foundation installed in the seabed, and subjected to regular waves. The buoy is equipped with an original internal non-linear rotative gravity pendulum system designed to control the heave motion of the buoy. This allows for the dynamic adjustment of wire tension, subsequently governing the power output of the buoy. Furthermore, this innovative design enables the buoy to adapt to a wide range of power requirements and environmental conditions. A mathematical model that employs potential theory and a linearized free-surface boundary condition is adopted to simulate the behavior of this elastically moored flexible multibody wave energy converter. The effectiveness of this design is thoroughly investigated through an extensive study. The influence of the mass and damping constants of the multibody device on the displacement response is also explored. A comparative analysis is performed numerically between devices with and without a parametric gravity pendulum exciting device. The study indicates the existence of both beat and prominent internal resonance phenomena, which warrant meticulous investigation in further studies. These findings have potentially significant implications for renewable energy production, particularly in coastal and offshore areas.
