A self-powered and self-sensing wave energy harvester based on a three-rotor motor of axle disk type for sustainable sea

The abundance of wave energy resources on ocean islands renders them an ideal natural platform for ocean monitoring. This is because the energy from the waves can be harnessed to power ocean monitoring sensors. This paper presents a self-powered and self-sensing three-stage rotor electromagnetic generator wave energy harvester (SS-WEH). The novel three-stage rotor generator configuration of the self-supply module demonstrates a superior power output compared to the single-rotor and inertial two-rotor structures used in previous studies. The maximum average power output achieved is 8.24 W within a frequency range of 1 Hz. PTO systems can achieve average power densities of up to 675 W/m³. Furthermore, the wave energy harvester functions as a self-sensing module, transmitting voltage signals to a computer terminal through a Wi-Fi module. This is achieved using a gated recirculation unit (GRU) deep learning model to monitor wave states and detect faults within the harvester system. The self-sensing module achieves an accuracy rate of 99.56 %. The wave energy harvester system proposed in this paper can simultaneously harvest wave energy, monitor ocean waves, and self-monitor system faults, which is crucial for advancing ocean resource development and monitoring.