• Title/Summary/Keyword: positive periodic solutions

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Use of Piezoelectric Effect in Portable Loadless Wind-Power Source for Ubiquitous Sensor Networks (유비쿼터스 센서네트워크를 위한 압전효과 기반의 무구속 휴대용 풍력 전원 장치)

  • Chang, Hyung-Kwan;Kim, Dae-Joong;Park, Jung-Yul
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.34 no.6
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    • pp.623-628
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    • 2010
  • This paper presents a wind-power-driven portable power source based on piezoelectric effect. Positive piezoelectric effect is one of efficient and widely used mechanisms for converting mechanical energy to electrical energy. However, for this mechanism, a periodic mechanical stress with a high frequency, as in the case of AC, has to be exerted; such stress cannot be exerted by the natural wind in the environment. The natural wind has a constant velocity with slow and irregular variations, as in the case of DC. In this paper, we propose a novel and simple mechanism to convert mechanical energy into electrical energy. The DC-like wind flow is passed through a propeller to convert it to an AC-like wind flow; the resultant AC-like periodic flow induces vibrations in a piezoelectric cantilever, thereby, generating electrical power. This system is expected to be one of practical solutions for wireless energy supply to ubiquitous sensor networks (USNs).