Non-Conventional Cantilever for Piezoelectric Energy Harvesting at Ultra Low Resonant Frequency

The piezoelectric energy harvester is the most prominent energy sources to sustain low power electronic devices which include mobile, wireless sensor nodes and biomedical applications etc. This paper demonstrates a non-conventional type cantilever structure based piezoelectric energy harvester. The sidewall of the proposed structure is in staircase shape, hole in the beam and a tip mass on the free end side. To achieve high output power at low-frequency range unimorph PZT-5H piezoelectric material is used in the cantilever beam. The proposed structure for proof mass is incorporated at the free side of the cantilever and a hole on the beam. The simulation measures the resonance frequency of the cantilever and for the different values of load output electrical power is estimated. The proposed work achieves the electric potential of 0.7 V at 53.4 Hz with 1.0 g of input acceleration. Based on the simulation this harvester reports output power for various values of loads ranging from 100 Ω to 100 MΩ. With the load value of 30 kΩ maximum output power attained is 300 ΩW.