Abstract
To downsize the clamp area and increase the output power of the harvester, we developed a miniature piezoelectric vibration energy harvester with combining a Z-shaped folded spring and a mechanically-switching SSHI (synchronized switch harvesting on inductor). The overall harvester size is 4×2×3 cm3. The FEM analysis revealed that the output power increases and the value of the 1st and 2nd resonance frequencies move closer as the angle of the Z-shaped spring decreases, therefore, the smaller angle would be more promising. The experimental results showed that the maximum output power of our harvester for the 1st (20.2 Hz) and 2nd (53.0 Hz) resonance frequencies at the applied acceleration of 4.9 m/s2 are 088 and 0.98 mW, respectively. The reason for a marked enhancement of the output power for the 2nd resonance frequency is attributed to the vertical movement of the 2nd vibrational mode which applies larger mechanical stress to the piezo ceramic and achieves better electrical contact between the tip of the Z-shaped spring and the spring plunger.
Highlights
IntroductionA piezoelectric vibration energy harvester (P-VEH), which typically consists of a piezoelectric material, beam, and additional mass, represents one promising power source for internet of things (IoT) modules because of the high output power density
The reason for a marked enhancement of the output power for the 2nd resonance frequency is attributed to the vertical movement of the 2nd vibrational mode which applies larger mechanical stress to the piezo ceramic and achieves better electrical contact between the tip of the Z-shaped spring and the spring plunger
A piezoelectric vibration energy harvester (P-VEH), which typically consists of a piezoelectric material, beam, and additional mass, represents one promising power source for internet of things (IoT) modules because of the high output power density
Summary
A piezoelectric vibration energy harvester (P-VEH), which typically consists of a piezoelectric material, beam, and additional mass, represents one promising power source for internet of things (IoT) modules because of the high output power density. In most cases, volume for clamping the beam accounts for a large portion of the harvester, which leads to decrease in the actual power density. We need to further increase the output power of P-VEHs to shorten the sensing period of the wireless sensor module. SSHI (synchronized switch harvesting on inductor) interface incorporating mechanical switch was developed to increase the output power and simplify the complexity of the circuit [1, 2]. To downsize the clamp volume and increase the output power, we propose a miniature P-VEH with combining a folded spring and a mechanically-switching SSHI
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
