Multi-directional extremely-low-frequency electromagnetic ocean wave energy harvester based on improved double pendulum structure

The study of ocean wave energy harvesting technology is of great importance in the field of distributed sensor energy supply. Aiming at the problems of insufficient output power, single direction of collecting vibration, restricted working frequency band and complex structure of traditional ocean wave energy harvesters of marine network nodes, a multi-directional extremely-low-frequency electromagnetic ocean wave energy harvester based on improved double pendulum structure is designed. The effect of different component parameters of the energy harvester on the output electrical performance is analyzed by simulation software and a constructed vibration test rig, and the relationship between output voltage and motion state is explored. After optimizing the structure, the ocean wave energy harvester has a minimum response frequency of about 0.25 Hz at a vertical wave height of 0.6 m and a minimum response flow speed of about 0.3 m/s in the horizontal direction. The peak output power is about 150 mW when the wave height is 0.6 m at a frequency of 1 Hz and about 110 mW when the horizontal speed is 0.9 m/s. Experimental results show that the energy harvester can better capture ocean wave energy and provide power for night lights and even IoT devices.