Abstract

Accurate predictions of the amount of harvestable energy available from ambient vibrations are important for design of energy harvesters and for their integration in specific applications. This need has motivated the development of many mathematical models for piezoelectric energy harvesters (PEHs). Existing models, however, require material and geometric PEH data that are often incorrect and/or unavailable. As a more accurate and practical means to meet this need, we propose an energy conversion model of a cantilevered PEH that requires only geometric data and modal parameters that can be directly measured using a standard vibration test. The newly proposed model facilitates calculation of the maximum output power and thus enables visualization of the harvestable energy from the target vibrating structure. Prediction accuracy of the proposed model was confirmed in our study through finite element analysis and experimental results. Practical use of the proposed energy conversion model was demonstrated by applying it to a cooling fan unit of a boiler facility in a power plant.