Finite Element Modeling of MEMS Piezoelectric Energy Harvester

L. Beker, A. Muhtaroglu, H.N. Ozguven, H. Kulah
Middle East Technical University, TR

Keywords: piezoelectric, MEMS, energy harvesting


This paper reports an improved method for modeling and optimization of a MEMS piezoelectric energy harvester (PEH) for a desired frequency range with maximum voltage output using finite element method. Single-degree-of-freedom and distributed parameter modeling methods have drawbacks for the design of MEMS PEH’s. Finite element method can be used to model and optimize MEMS PEH’s by using SOLID226 element available in ANSYS. In this paper a MEMS PEH is modeled with resonance frequency, maximum stress and dimensional constraints. A study on the meshing is done by considering free mesh, brick mesh and size of elements. A batch run code is developed consisting of modal and harmonic analysis. Developed code is executed using built-in optimization methods 2000 times consecutively to find global maximum value for voltage within desired ranges. Common problem of modeling piezoelectric transducers is the piezoelectric constants used in the simulation. Because the information supplied by manufacturers is not suitable with the input required by ANSYS and this problem is also discussed in the paper. Proposed method can also be applied to designing of various piezoelectric transducers.