ENERGY HARVESTING USING FREQUENCY VIBRATION OF MEMS STRUCTURE

Abstract

Research into energy harvesting from ambient vibration sources has attracted great interest over the last few years, largely as a result of advances in the areas of wireless technology and low-power electronics. One of the mechanisms for converting mechanical vibration into electrical energy is the use of piezoelectric materials, typically operating as a cantilever in a bending mode, which generate a voltage across the electrodes when they are stressed. Typically, the piezoelectric materials are deposited on a non-electro-active substrate and are physically clamped at one end to a rigid base. So far different models of cantilever structures like simple cantilever, tuning fork etc., have been proposed as energy harvesting modules but the problems with them, has been that they offer very high input impedance resulting in very small current drawn into the network followed to the energy harvesting device.
The work on energy harvesting using MEMS thus far focused on mainly different cantilever structures which faces the problems like high impedance, low current and low energy convergence efficiency. So the motivation behind this project is to minimize the loss during energy conversion, to make high resonant frequency structure so as to minimize electrode spacing to maximize the current output and to make the low power devices self powered without any environmental impact. Thus, in this work, we propose a diaphragm based MEMS structure