High-Level Vibration for Single-Frequency and Multi-Frequency Excitation in Macro-Composite Piezoelectric (MFC) Energy Harvesters, Nonlinearity, and Higher Harmonics

Abstract

This paper presents an extensive experimental investigation to identify the influence of signal parameters on a piezoelectric harvester’s performance. A macro-fibre composite energy harvester was studied as an advanced, flexible, high-performance energy material. Gaussian white noise, and single-frequency and multi-frequency excitation were used to investigate nonlinearity and multiple-frequency interactions. Using single low and high frequencies, we identified the nonlinearity of the harvester’s vibration. Multi-frequency excitation with a series of low-to-high-frequency harmonics mimicked the practical vibration signal. Under such multi-frequency excitation, the harvester’s nonlinear behaviour was studied. Finally, the interaction effects among multiple frequencies were identified. The results show that under pure resonant excitation, high-level vibration led to high-level mechanical strain, which caused nonlinear vibration behaviour. Moreover, it was shown that the different harmonics excited the various structure bending modes, which caused the nonlinearity of multi-frequency excitation. The first four harmonics of the real-time signal were important. The experimental results emphasise the resonant nonlinearity and interactions of multi-frequency excitation effects.

Research and Design of Energy-Harvesting System Based on Macro Fiber Composite Cantilever Beam Applied in Low-Frequency and Low-Speed Water Flow

“…However, 71% of the Earth’s surface is covered by oceans, and most natural water bodies have low-frequency and low-velocity water flows [ 29 , 30 , 31 , 32 ]. Therefore, harnessing low-frequency and low-velocity water flows has been a persistent challenge.…”

“…However, due to limitations in material sensitivity, more research is needed on collecting low-frequency, low-speed, and weak vibration energy. However, 71% of the Earth's surface is covered by oceans, and most natural water bodies have low-frequency and low-velocity water flows [29][30][31][32]. Therefore, harnessing low-frequency and low-velocity water flows has been a persistent challenge.…”

An Impact-Based Piezoelectric Energy Harvester Utilizing Spherical Mass Collision Phenomenon

“…For instance, the narrow frequency band of PEHs complicates frequency matching between environment vibration and the harvester's natural frequency. There are several techniques, such as adding tip mass, that can mitigate this issue to some extent [6], but achieving frequency matching for low-frequency environmental vibrations (e.g., 1~2 Hz), remains a significant challenge. Therefore, the performance of PEHs under low-frequency vibrations is reduced remarkably.…”