Method for controlling vibration by exploiting piecewise-linear nonlinearity in energy harvesters

Abstract

<jats:p>Vibration energy is becoming a significant alternative solution for energy generation. Recently, a great deal of research has been conducted on how to harvest energy from vibration sources ranging from ocean waves to human motion to microsystems. In this paper, a theoretical model of a piecewise-linear (PWL) nonlinear vibration harvester that has potential applications in variety of fields is proposed and numerically investigated. This new technique enables automatic frequency tunability in the energy harvester by controlling the gap size in the PWL oscillator so that it is able to adapt to changes in excitations. To optimize the performance of the proposed system, a control method combining the response prediction, signal measurement and gap adjustment mechanism is proposed in this paper. This new energy harvester not only overcomes the limitation of traditional linear energy harvesters that can only provide the maximum power generation efficiency over a narrow frequency range but also improves the performance of current nonlinear energy harvesters that are not as efficient as linear energy harvesters at resonance. The proposed system is demonstrated in several case studies to illustrate its effectiveness for a number of different excitations.</jats:p>

Frequency tunable electromagnetic vibration energy harvester using piecewise linear nonlinearity

“…With these values determined, the entire vibration cycle for any gap size can be constructed. For a more detailed explanation of the BAA method, refer to previous works on this topic [34,35].…”

“…This process is then repeated during the operation of the device. The previous computational study showed that this design performs more effectively than many other VEHs for a number of cases since it can operate efficiently for a wide variety of excitation conditions [34].…”

“…In order to overcome these obstacles to effective energy harvesting, a new PWL nonlinear harvester has recently been proposed and numerically investigated [34]. In the proposed design, an actively controlled mechanical stopper is positioned across from the traditional linear VEH.…”

“…These results are then compared with the computational predictions. Modifications were made to the previous idealized computational model presented in [34] to account for parameters not considered in the previous idealized study. The remainder of this work is organized as follows.…”

Experimental Modelling and Amplitude-Frequency Response Analysis of a Piecewise Linear Vibration System

“…Yao et al [23] attached a nonlinear energy sink (NES) with piecewise linear stiffness to suppress the vibration of a forced primary vibration system, and the effectiveness of the NES was proven by experiments. In design of energy harvesters, Tien and D'souza [24] proposed a new vibration harvester composed of a piecewise linear oscillator and an adjustable gap, which has an optimal vibration performance over a broad frequency range and the best performance at resonance. Zhang et al [25] experimentally designed a vibration harvester with piecewise linear stiffness characteristic, which may work in a broadband and low-frequency range.…”