Piezoelectric energy harvesting with a clamped circular plate: Analysis

Energy harvesting using piezoelectric materials is not a new concept, but its small generation capability has not been attractive for mass energy generation. For this reason, little research has been done on the topic. Recently, increased interest in wearable computer concepts and remote electrical devices has provided motivation for more extensive study of piezoelectric energy harvesting. The theory behind cantilever-type piezoelectric elements is well known, but the transverse moving plate elements, which can be used in energy generation from pressure sources is not yet fully developed. The power generation in a pressure-loaded plate depends on several factors. Among them, the thickness of each layer is important, as is the electrode pattern used. In this article, two clamped circular plate structures, a fully electroded unintorph, and a so-called regrouped electrode unimorph, are modeled. These models are then used to calculate energy generation with varying thickness ratios. The results of this analysis are presented with an eye toward guidelines for design of useful energy harvesting structures.