ANALYSIS AND CHARACTERIZATION OF PIEZOELECTRIC ENERGY HARVESTING FROM GALLOPING AND BASE EXCITATIONS WITH COMPLEX ELECTRICAL CIRCUITRY

摘要

The characteristics and performance of piezoelectric energy harvesters concurrently subjected to galloping and base excitations when using a complex electrical circuit are studied. The considered energy harvester is composed of a bilayered cantilever beam with a square cylindrical structure at its tip. Euler-Bernoulli beam theory, nonlinear quasi-steady hypothesis, and Galerkin method are used to develop a reduced order model of this system. The electrical circuitry of the harvester consists of a load resistance, a capacitance, and an inductance. The impacts of the electrical components of the harvester's circuitry, the wind speed, and the base excitation frequency and acceleration on the broadband characteristics of the harvester, quenching phenomenon, and appearance of new nonlinear behaviors are deeply investigated and discussed. When both coupled frequencies of electrical and mechanical types exists and are far from each other, it is shown that the quenching phenomenon is only related to the coupled frequency of mechanical type. Unlike the existence of the quenching phenomenon, the results show that the beating phenomenon takes place for different excitation frequencies when they are close to the coupled frequencies of electrical and mechanical types.