Low power energy harvesting with piezoelectric generators.

摘要

Energy harvesting using piezoelectric material is not a new concept, but its generation capability has not been attractive for mass energy generation. For this reason, little research has been done on the topic.;Recently, concepts such as wearable computers, as well as small portable electrical devices have re-ignited the study of piezoelectric energy harvesting. The theory behind cantilever type piezoelectric elements is well known, but transverse moving diaphragm elements, which can be used in pressure type energy generation have not been yet fully developed. Power generation in a diaphragm depends on several factors. Among them, the thickness of each layer, the poling direction, and stress distribution are most important. In this thesis, unimorph and triple-morph diaphragm structures with various poling configurations were considered. Their energy generation was calculated with varying thickness ratios and poling directions at various locations using piezoelectric constitutive equations. The results of this analysis are presented, along with experimental results that indicate that an optimal electrode pattern will result in maximum electrical energy generation.