Analysis of Nonlinear Spring Arm for Improved Performance of Vibrational Energy Harvesting Devices

Abstract

Abstract. Recently, a number of attempts have been made to increase the operational bandwidth of the energy harvesting devices. Nonlinear mechanisms are one of them. In this paper, we report design and analytical formulation of stretching strain of an electromagnetic energy harvester on FR4 material under large deformation of the spring arms. It is found that nonlinearity has an inverse square dependence on thickness of the arms. Numerical solution of a monostable Duffing oscillator that governs the dynamics of such a large deformed nonlinear energy harvester showed that with decrease of load resistance, the average power output increases, where the output response depends strongly on the input force. For small input acceleration, the desired large amplitude vibration does not come into play and the response becomes linear. However, for higher input acceleration nonlinearity appears and the operational bandwidth increases, at the same time, output power level also increases.

Parameter sensitivity of an in-plane gap closing electrostatic energy harvester with end-stop impacts

“…Increasing the Gaussian white noise level added to a harmonic excitation decreases the jump-down frequency of the device, as shown in Figure 18. These noise levels are comparable to other reported noise levels that are used to harvest energy (Le et al, 2013; Le and Halvorsen, 2012; Mallick et al, 2013, 2015). The input accelerations are generated as random signals with different spectral densities.…”

“…In order to enhance the frequency response of the harvester, nonlinearities are introduced into the harvesters’ response (Basset et al, 2014; Blystad and Halvorsen, 2011; Hoffmann et al, 2011; Mann and Owens, 2010; Wang and Hansen, 2014). The nonlinearities can either intentionally be designed in Mallick et al (2013) or can appear as side effects when harvester operates at sufficiently strong excitations (Basset et al, 2014; Blystad and Halvorsen, 2011; Hoffmann et al, 2011). Mechanical end-stops introduced in the harvesters’ design stop motion of the proof mass beyond defined limits.…”

Modelling of Electromagnetic Coupling in Micro-scale Electromagnetic Energy Harvester

“…It consists of a block magnet which is vibrating on the non-linear spring near a flat square coil. This device actually has not only the progressive mode, but also the rotational one [11]. However, these methods could also be implemented for the rotational motion.…”