Design and Simulation of a Piezoelectric Cantilever Beam for Mechanical Vibration Energy Harvesting

Abstract

This paper presents the design and simulation of a piezoelectric cantilever beam for energy harvesting based on ambient mechanical vibration. The energy harvesting process is facilitated by the forward piezoelectric effect, which converts mechanical energy into electrical energy during detection of ambient vibration by the cantilever beam. The cantilever beam model consists of two piezoelectric layers and an elastic layer clamped to a vibrating host structure at one end, as well as a tip mass mounted at the other end. Using COMSOL Multiphysics, a comparative analysis of the cantilever beam's simulated output characteristics was conducted. These characteristics were analyzed with respect to varying input parameters such as resonant frequency, load resistance and length-width ratio of the cantilever beam. Uased on the simulation results, an optimized model of the cantilever beam was eventually developed. A maximum output power of 4.4 mW and DC output voltage of10.1 V was generated by the model at $4~\mathrm {k}\Omega $ load resistance, at a mechanical acceleration of 1 g and a resonant frequency of 75 Hz.