An orientation-adaptive electromagnetic energy harvester scavenging for wind-induced vibration

Wind energy is widely distributed, pollution-free and sustainable. Harvesting wind-induced vibration energy is a promising way to build self-powered systems. However, most of the current wind-induced vibration energy harvesters are unidirectional directional and insensitive to the frequently changing in wind direction. To overcome the difficulty, this work proposes an orientation-adaptive electromagnetic energy harvester (EMEH). By introducing a rotatable bluff body, the EMEH could be self-regulated to cater for the wind flow direction. Experimental results showed that the output power of the proposed EMEH could be enhanced greatly with the increase of rotatory inertia of the rotating bluff body. And, when the stiffness of the elastic beam is high, the output performance of the EMEH can be guaranteed by increasing the rotatory inertia of the rotatable bluff body. The output power of the optimized rotating bluff body and the elastic beam is 0.498 mW and 0.673 mW at wind speeds of 5.22 m/s and 8.0 m/s, respectively.