Fundamental issues in nonlinear wideband-vibration energy harvesting

TL;DR

This paper investigates the theoretical limits and practical advantages of nonlinear wideband-vibration energy harvesters driven by broadband vibrations, comparing their performance to linear counterparts and exploring specific nonlinear potentials.

Contribution

It derives an upper bound on output power for nonlinear harvesters and demonstrates that linear harvesters can achieve this bound under certain conditions, while also discussing nonlinear benefits.

Findings

Upper bound on output power derived

Linear harvesters can match the performance of nonlinear ones under certain conditions

Numerical analysis of nonlinear potentials shows their practical merits

Abstract

Mechanically nonlinear energy harvesters driven by broadband vibrations modeled as white noise are investigated. We derive an upper bound on output power versus load resistance and show that, subject to mild restrictions that we make precise, the upper-bound performance can be obtained by a linear harvester with appropriate stiffness. Despite this, nonlinear harvesters can have implementation-related advantages. Based on the Kramers equation, we numerically obtain the output power at weak coupling for a selection of phenomenological elastic potentials and discuss their merits.