Design of piezoelectric energy harvesting devices and laminate structures by applying topology optimization

摘要

The advances in miniaturization techniques over the last decades has made the widespread of electronic devices greater than ever and the rate of growth increases each day. Research has been carried out all over the world aiming at developing devices capable of capturing ambient energy and converting it into useable energy in this very promissing field of energy harvesting. Piezoelectric laminates have been used in the design of energy harvesting systems. While most of current research considers traditional assemblies with bimorph transducers and proof masses, this work involves the design of novel energy harvesting devices and other laminate piezoelectric structures by applying topology optimization, which combines Finite Element Method with optimization algorithms. The finite element employs a robust formulation capable of representing both direct and converse piezoelectric effects, based on the MITC formulation. The topology optimization uses the PEMAP-P model (Piezoelectric Material with Penalization and Polarization) combined with the RAMP model (Rational Approximation of Material Properties), where the design variables are the pseudo-densities that describe the amount of piezoelectric material at each finite element. A multi-objective function is defined for the optimization problem, which aims at designing eigenvalues and eigenvectors and maximizing the electromechanical coupling of a specific mode. This paper presents the implementation of the finite element and optimization software and shows results achieved.