High temperature vibration energy harvester system

Abstract

This work presents the first demonstration of a high temperature piezoelectric energy harvester system, capable of operation up to 300°C. The system comprises of a PZT piezoelectric energy harvester with a silicon carbide Schottky diode full wave rectifier, which can rectify the AC supplied by the piezoelectric harvester at higher temperatures than conventional silicon components. When the harvester is driven at 400mg (3.9ms <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-2</sup> ), into a matched load, the rectifier delivers 320μW at room temperature, falling to 80μW at 300°C. This is caused by a combination of increased mechanical damping, decreased electromechanical coupling coefficient (K <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">sys</sub> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ) and an increase in the dielectric constant of the PZT.