Development of a magnetoelectric microgenerator to harvest electrical energy based on electromagnetic effect

Abstract

Abstract The field of energy harvesting has grown rapidly, stimulated by the increasing demand for low-power devices and the expansion of the Internet of Things (IoT). Electromagnetic induction stands out as one of the most efficient and extensively implemented methods among energy harvesting phenomena. The main purpose of this study is to design a magnetoelectric microgenerator that uses an innovative electromagnetic technique, aiming to replace batteries in some applications while maintaining a comparable size. The innovative technique we used involves abruptly altering the direction of magnetic flux in a mechanical system, whereas the classical technique typically requires moving a magnet relatively to a coil and vice versa. To determine the quantity of electrical energy and voltage harvested by this new electromagnetic technique, two microgenerators were designed. The first was developed as a prototype, on which we carried out research to study the impact of various mechanical parameters on the electrical response of this technology. After optimizing these mechanical parameters, we developed a final miniaturized microgenerator with a volume comparable to that of AA batteries, making it a potential replacement for conventional batteries to power low-consumption devices. The first prototype weighs 210 g and has a volume of 38.5 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:msup> <mml:mtext>cm</mml:mtext> <mml:mn>3</mml:mn> </mml:msup> </mml:mrow> </mml:math> . It consists of two neodymium magnets, a coil with 1300 turns, a ferromagnetic lever that manipulates the magnetic flux, and two ferromagnetic cores. The electrical variables were determined at different sections of the ferromagnetic lever under an exerted force of 8 N. The research conducted on the first prototype led to develop a miniaturized microgenerator that harvested approximately 1.45 mJ of energy and generated a voltage of 5.4 V. The amount of electricity provided by the developed harvester is more than enough to power several electronic devices at once.