Theoretical and Experimental Studies on MEMS Variable Cross-Section Cantilever Beam Based Piezoelectric Vibration Energy Harvester

Abstract

The piezoelectric vibration energy harvester (PVEH) based on the variable cross-section cantilever beam (VCSCB) structure has the advantages of uniform axial strain distribution and high output power density, so it has become a research hotspot of the PVEH. However, its electromechanical model needs to be further studied. In this paper, the bidirectional coupled distributed parameter electromechanical model of the MEMS VCSCB based PVEH is constructed, analytically solved, and verified, which laid an important theoretical foundation for structural design and optimization, performance improvement, and output prediction of the PVEH. Based on the constructed model, the output performances of five kinds of VCSCB based PVEHs with different cross-sectional shapes were compared and analyzed. The results show that the PVEH with the concave quadratic beam shape has the best output due to the uniform surface stress distribution. Additionally, the influence of the main structural parameters of the MEMS trapezoidal cantilever beam (TCB) based PVEH on the output performance of the device is theoretically analyzed. Finally, a prototype of the Aluminum Nitride (AlN) TCB based PVEH is designed and developed. The peak open-circuit voltage and normalized power density of the device can reach 5.64 V and 742 μW/cm3/g2, which is in good agreement with the theoretical model value. The prototype has wide application prospects in the power supply of the wireless sensor network node such as the structural health monitoring system and the Internet of Things.

Design and test of liquid sloshing piezoelectric energy harvester

“…The use of piezoelectric materials can convert the ubiquitous vibration energy in the environment into electrical energy and store it, which can then be supplied to wireless sensor nodes for power, saving energy and meeting long-term service requirements. [4][5][6] However, conventional cantilever beam piezoelectric energy harvesters have a narrow frequency band and poor environmental 1 School of Transportation and Vehicle Engineering, Shandong University of Technology, Zibo, Shandong, P.R. China 2 adaptability, and can only collect vibration energy efficiently in a resonant state.…”

Analysis of Dynamic Characteristics of Tristable Exponential Section of Piezoelectric Energy Harvester

“…Because the bending stress of the rectangular cantilever beam changes along the length, the maximum power output of the bending stress is the highest at the fixed end, and the minimum power output tends to zero at the free end. The variable-cross-section beam vibration energy harvester can optimize the uniform distribution of a PZT patch strain along the length of the piezoelectric beam well and improve the power generation power of the piezoelectric sheet pasted on both sides of the cantilever beam root [27,28].…”

“…Ma et al [32] and Tan et al [33] studied the trapezoidal-cross-section cantilever piezoelectric energy harvester and proved that the stress distribution in the trapezoidal cantilever is more uniform than that in the rectangular cantilever, and the trapezoidal-cantilever piezoelectric energy harvester has a higher voltage output. He et al [27] compared trapezoidal and rectangular piezoelectric vibration energy harvesters. The piezoelectric vibration energy harvester with a concave beam shape has a uniform surface stress distribution and performs the best output.…”

A Cantilever-Based Piezoelectric MEMS for Arbitrary XY Path Generation

“…In this area, the development in recent years of smart materials can be of great help. Among them, piezoelectric materials are widely used in various fields such as vibration damping [26][27][28][29], energy harvesters [30,31], etc. The piezoelectric actuation has been increasingly adopted and offers an alternative to the more widespread electrostatic and thermal actuation systems.…”