Modeling and Characterization of a Kinetic Energy Harvesting Device Based on Galfenol

Abstract

The proposal of Energy Harvesting (EH) techniques and devices has experienced a significant growth over the last years, because of the spread of low power electronic devices. Small ambient energy quantities can be recovered through EH and exploited to power Wireless Sensor Networks (WSN) used, for example, for the Structural Health Monitoring (SHM) of bridges or viaducts. For this purpose, research on EH devices based on magnetostrictive materials has significantly grown in the last years. However, these devices comprise different parts, such as a mechanical system, magnetic circuit and electrical connections, which are coupled together. Then, a method able to reproduce the performance may be a handy tool. This paper presents a nonlinear equivalent circuit of a harvester, based on multiple rods of Galfenol, which can be solved with standard circuit simulator. The circuital parameters are identified with measurements both on one rod and on the whole device. The validation of the circuit and the analysis of the power conversion performance of the device have been conducted with different working conditions (force profile, typology of permanent magnets, resistive electrical load).

Self-Similarity in Magnetostrictive Materials: An Experimental Point of View

“…It is worth pointing out that the variable u, as shown in the following, appears to be substantial in modeling magnetostriction. Indeed, a suitable choice of u allows for building up an analytical phenomenological description of the most common magnetostrictive behavior, as reported in Reference [12]. Moreover, in this paper, we show this particular viewpoint of the self-similarity property, based on the experimental measurements, similar to what was done in Reference [8,9] for magnetocaloric materials with ferro-to-paramagnetic phase transitions.…”

Analysis of the Key Factors Affecting the Capability and Optimization for Magnetostrictive Iron-Gallium Alloy Ambient Vibration Harvesters

“…It can be concluded that the iron-gallium alloy MSM vibration energy harvesting system has the strongest ability to output electric power when the connected load resistance is close to the resistance of the pick-up coils and with a proper matching capacitance. This conclusion also partly described in [36]. Therefore, it is necessary to ensure that the external load matches with the pick-up coils impedance as much as possible.…”

“…In 2017, Clemente et al [35] presented an equivalent circuit which was a nonlinear three-port circuit, in which, the magneto-mechanical modeling was quite realistic and exploited nonlinear functions and the full coupling among the involved physical quantities of the employed magnetostrictive material. In 2019, Clemente et al [36] presented a nonlinear equivalent circuit of a harvester based on multiple rods of Galfenol, which was able to predict the output voltage and harvested power for different loads and pickup coils connections. Compared to the piezoelectric cantilever harvesters dating back to the 1990s, further efforts are needed to optimize this technology by thoroughly understanding the underlying phenomena that occur throughout the harvester.…”

Numerical Analysis of Signal Response Characteristic of Piezoelectric Energy Harvesters Embedded in Pavement

“…The development of low-cost, decentralized, and sustainable energy is a necessity to facilitate a wide application of embedded, off-grid sensors [4]. Environmental energy harvesting is the process of transforming the energy that exists in the environment (such as light, heat, mechanical, electromagnetic, biological, and wind energy, among others) into electricity that can be used; it is a potential way to extend the service life of embedded, off-grid sensors [5]. Pavements are designed for millions of axle's loads during service, which absorbs large amount of wasted mechanical energy.…”