A Multi-Mode Spiral Piezoelectric Energy Harvester With Wide Frequency Band

In order to improve the power density and broaden the frequency band of the piezoelectric energy harvester, a novel multi-mode spiral piezoelectric energy harvester (MSPEH) is designed with the linear multi-frequency resonance method in this work. A multi-DOF (Degree-Of-Freedom) lumped parametric model and an electromechanically coupled model is established to analyze the resonant frequency and output performance of the MSPEH. The proposed spiral multi-mode structure adopts the LMR-method to achieve three resonant frequencies (36.8 Hz, 40.1 Hz and 42.5 Hz), effectively broadening the frequency band while increasing the normalized power density of the three modes to 38.14, 14.89, and 6.99 (Unit:
$\mu \text{W}\cdot $
Hz
$\cdot $
kg
$\cdot \text{s}^{{4}}\cdot \text{m}^{-{2}}\cdot $
mm
$^{-{3}}{)}$
.