A Novel Design to Increase the Power Output of an Electromagnetic Vibration Energy Harvester Using Finite Element Analysis

The concept of Internet of Things has prompted the need for a sustainable energy source to power wireless sensor networks. Vibration energy harvesting emerges as an applicable option. This paper presents a finite element analysis of a new electromagnetic vibration energy harvester design aimed to increase the power output of an electromagnetic vibration energy harvester by making the coil and a pair of magnets vibrate in the opposite direction, hence increasing the speed of the coil cutting through the magnetic flux of the magnets. The design consist of a regular cantilever beam And one uniquely shaped cantilever beam designed to move in the opposite direction to the regular beam under the same base excitation. Results show that due to the opposite motion, the speed of the coil moving through the magnetic flux for the new design is equal to the sum of velocities from the two individual beams. This lead to a 99.3% increase in power output generated from the new design when compared with the sum of the individual power outputs produced by the two beams. Further analysis demonstrates that the maximum power decreases if a time lag was introduced between the two beams, hence stating the importance of matching their natural frequencies.