Modeling of Piezoelectric MEMS Vibration Energy Harvesters

Abstract

This chapter discusses the use of piezoelectric microelectromechanical system energy-harvesting devices to supply power to a miniature wireless sensor node. It deals with a generic unidimensional model of an energy harvester followed by more detailed analytical models of actual geometrical structures common in microelectromechanical system (MEMS) implementations of piezoelectric energy harvesters. The chapter also discusses various methods of implementing the presented models, ranging from finite element method (FEM) to VHDL-AMS behavioral models. The physical and geometrical parameters of the energy-converting devices are only considered at the very low level of the design flow, typically using simplistic analytical models or FEM tools. Multiple piezoelectric materials are known, but only very few are available as thin layers to be used in MEMS. The materials most commonly considered for integration in MEMS devices are aluminum nitride, piezoelectric thin layer, zinc oxide, lithium niobate, and lead magnesium niobate-lead titanate.