Numerical and experimental investigation of an Inertial Tilting hybrid wave energy converter for powering small-scale marine systems

Abstract

The increasing global demand for marine resource exploration, maritime rights protection, and deep-sea engineering applications highlights the need for the diversification of marine engineering equipment and the expansion of its deep-sea capabilities, presenting significant technical and economic value. As the use of small-scale marine engineering equipment in deep-sea environments becomes more prevalent, optimizing energy supply methods for such equipment is critical to ensure their durability and efficiency in complex marine conditions. This paper proposes an Inertial Tilting Electromagnetic-Triboelectric Hybrid Energy Converter (ITHEC), which efficiently harvests energy from ocean waves to power small marine engineering devices. A comprehensive design and optimization framework was developed for this energy converter. This framework was based on theoretical analysis and simulations of structural dynamics and characteristics. Validation experiments were conducted using a custom-built structural characteristics testing platform. The results showed that under horizontal harmonic motion excitation with an amplitude of d = 60 mm and a frequency of f = 1.5Hz, the open-circuit voltages of the triboelectric nanogenerator (TENG) and electromagnetic generator (EMG) reached 60V and 0.23V, respectively, with short-circuit currents of 1.3 μA and 2.2 mA, and peak power densities of 1.18 mW/m² and 0.51 mW/m². When arrayed, the hybrid energy converter can meet the operating current requirements of small marine sensors. This study offers an innovative solution for energy supply challenges in small marine equipment and establishes the practical viability of hybrid power systems for marine energy harvesting.