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Title: Performance of improved magnetostrictive vibrational power generator, simple and high power output for practical applications

Abstract

Vibration based power generation technology is utilized effectively in various fields. Author has invented novel vibrational power generation device using magnetostrictive material. The device is based on parallel beam structure consisting of a rod of iron-gallium alloy wound with coil and yoke accompanied with permanent magnet. When bending force is applied on the tip of the device, the magnetization inside the rod varies with induced stress due to the inverse magnetostrictive effect. In vibration, the time variation of the magnetization generates voltage on the wound coil. The magnetostrictive type is advantageous over conventional such using piezoelectric or moving magnet types in high efficiency and high robustness, and low electrical impedance. Here, author has established device configuration, simple, rigid, and high power output endurable for practical applications. In addition, the improved device is lower cost using less volume of Fe-Ga and permanent magnet compared to our conventional, and its assembly by soldering is easy and fast suitable for mass production. Average power of 3 mW/cm{sup 3} under resonant vibration of 212 Hz and 1.2 G was obtained in miniature prototype using Fe-Ga rod of 2 × 0.5× 7 mm{sup 3}. Furthermore, the damping effect was observed, which demonstrates high energy conversion of the generator.

Authors:
 [1]
  1. Kanazawa University, Kakuma-machi, Kanazawa-city, Ishikawa 920-1192 (Japan)
Publication Date:
OSTI Identifier:
22409932
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 117; Journal Issue: 17; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; BENDING; COMPARATIVE EVALUATIONS; ELECTRIC POTENTIAL; ENERGY CONVERSION; GALLIUM ALLOYS; IMPEDANCE; IRON ALLOYS; MAGNETIC MATERIALS; MAGNETIZATION; MAGNETOSTRICTION; MECHANICAL VIBRATIONS; PERMANENT MAGNETS; PIEZOELECTRICITY; POWER GENERATION; RODS; STRESSES

Citation Formats

Ueno, Toshiyuki, E-mail: ueno@ec.t.kanazawa-u.ac.jp. Performance of improved magnetostrictive vibrational power generator, simple and high power output for practical applications. United States: N. p., 2015. Web. doi:10.1063/1.4917464.
Ueno, Toshiyuki, E-mail: ueno@ec.t.kanazawa-u.ac.jp. Performance of improved magnetostrictive vibrational power generator, simple and high power output for practical applications. United States. doi:10.1063/1.4917464.
Ueno, Toshiyuki, E-mail: ueno@ec.t.kanazawa-u.ac.jp. Thu . "Performance of improved magnetostrictive vibrational power generator, simple and high power output for practical applications". United States. doi:10.1063/1.4917464.
@article{osti_22409932,
title = {Performance of improved magnetostrictive vibrational power generator, simple and high power output for practical applications},
author = {Ueno, Toshiyuki, E-mail: ueno@ec.t.kanazawa-u.ac.jp},
abstractNote = {Vibration based power generation technology is utilized effectively in various fields. Author has invented novel vibrational power generation device using magnetostrictive material. The device is based on parallel beam structure consisting of a rod of iron-gallium alloy wound with coil and yoke accompanied with permanent magnet. When bending force is applied on the tip of the device, the magnetization inside the rod varies with induced stress due to the inverse magnetostrictive effect. In vibration, the time variation of the magnetization generates voltage on the wound coil. The magnetostrictive type is advantageous over conventional such using piezoelectric or moving magnet types in high efficiency and high robustness, and low electrical impedance. Here, author has established device configuration, simple, rigid, and high power output endurable for practical applications. In addition, the improved device is lower cost using less volume of Fe-Ga and permanent magnet compared to our conventional, and its assembly by soldering is easy and fast suitable for mass production. Average power of 3 mW/cm{sup 3} under resonant vibration of 212 Hz and 1.2 G was obtained in miniature prototype using Fe-Ga rod of 2 × 0.5× 7 mm{sup 3}. Furthermore, the damping effect was observed, which demonstrates high energy conversion of the generator.},
doi = {10.1063/1.4917464},
journal = {Journal of Applied Physics},
number = 17,
volume = 117,
place = {United States},
year = {Thu May 07 00:00:00 EDT 2015},
month = {Thu May 07 00:00:00 EDT 2015}
}
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