Design and analysis of a hollow triangular piezoelectric cantilever beam harvester for vibration energy collection

Abstract

The vibration of transportation infrastructure is random and of low frequency. The vibration energy can be collected and converted into electric energy by installing the piezoelectric cantilever beam (PCB) harvesters on the transportation infrastructure. The resonance frequency and the resonance number of the PCB harvesters within the low frequency range play critical roles. This paper presents an analysis of four types of PCB harvesters designed according to the characteristics mentioned above to evaluate the influence of three different shapes (rectangle, trapezoid and triangle) on the power generation capacity of the piezoelectric cantilever beams. The results show that the triangular PCB harvesters are more suitable for the low-frequency vibration environment of transportation infrastructure, and they usually have higher voltage outputs. In order to widen the resonant frequency of the triangular cantilever to better adapt to the random vibration environment of the transportation infrastructure, the performance of a hollow triangular piezoelectric cantilever beam (HTPCB) was also assessed. Through modeling and analysis, the resonant frequency of the HTPCB has a broader low frequency range. In practical applications, deployment of the HTPCB harvesters on transportation infrastructures such as pavements and bridges can collect more energy in the random and low-frequency vibration environment of the transportation infrastructures.