Electromagnetic Energy Harvester for Low Frequency Vibrations Using MEMS

Abstract

This paper proposes design and analysis of electromagnetic energy harvester using MEMS technology. The energy harvester is intended to harvest energy from low frequency ambient vibrations that is less than 100Hz. The design would consist of a cantilever which is the simplest MEMS structure which can further be used to power the amplifiers. These amplifiers can be used to amplify the low amplitude and low frequency vibration signals. The work intends to explore the opportunities in harnessing vibrations induced by the live loads, such as laden Lorries & Buses on bridges, to harvest energy in the form of generated voltage. A cantilever based electromagnetic energy harvester can be employed to capture these miniscule level of vibrations and convert them into electrical energy. The Faraday's law of electromagnetic induction is the fundament idea utilized to design the cantilever beam simulated with dimensions of 2500x500μm. The material plays a vital role in sensitivity and hence NdFeB is selected as magnetic material whereas Aluminum as the conducting coil electrode material. The voltage of 2.34mV is generated using single cantilever beam energy harvester. An array of six such cantilevers generates a voltage of 3.27mV. The simulation results confirm that the low ambient vibrations can be effectively utilized to generate useful energy.