• 제목/요약/키워드: 소음의 감쇠

검색결과 537건 처리시간 0.162초

Updating of Finite Element Models Including Damping (감쇠를 포함한 유한요소 모형의 개선)

  • Lee, Gun-Myung;Ju, Young-Ho;Park, Mun-Soo
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • 제22권12호
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    • pp.1243-1249
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    • 2012
  • Finite element models are updated in two stages in this paper. In the first stage, damping is neglected, and mass and stiffness matrices of a finite element model are updated using an optimization technique. The objective function for optimization consists of natural frequencies and mode shapes obtained from experimental modal testing data and finite element analysis. In the second stage, damping is considered with the mass and stiffness matrices fixed. A damping matrix is estimated assuming a proportional damping system. Then the damping matrix is adjusted using an optimization process so that the difference between the analytical and measured frequency response functions becomes minimum. This procedure of model updating has been applied to a simulated system and an experimental cantilever beam.

Vibration Suppression of a Cantilever Beam Using MTMD (MTMD를 이용한 보의 진동 억제)

  • Bae, Jae-Sung;Hwang, Jai-Hyuk;Kim, Jong-Hyuk;Lim, Jae-Hyuk
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • 제21권12호
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    • pp.1091-1097
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    • 2011
  • In the present study, TMD(tuned mass damper) with eddy current damping is proposed to suppress the vibration of a cantilever beam effectively. The advantages of TMD are that it is simple and its performance are excellent at any particular frequency. However, TMD may have the low performance at other frequency. To solve this problem and improve its performance, this study applies the eddy current damping to TMD. This TMD with ECD is named as MTMD(magnetically tuned mass damper). MTMD is designed for the vibration suppression of a cantilever beam. The mathematical modeling, simulation, and experiments of the cantilever beam with MTMD are performed. From analytic and experimental results, it can be concluded that the vibration suppression performance of MTMD are excellent.

A Variable Leakage Inductance Common-Mode Choke (누설인덕턴스 가변형 공통모드 초크코일)

  • Baek, Mi-Ran;Kim, Hee-Seung;Won, Jae-Sun;Ju, Jae-Chul;Oh, Dong-Sung;Han, Sang-Kyoo;Hong, Sung-Soo
    • Proceedings of the KIPE Conference
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    • 전력전자학회 2011년도 전력전자학술대회
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    • pp.402-403
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    • 2011
  • EMI 필터 설계 시 주로 사용되는 공통모드 초크의 경우 자화 인덕턴스로부터 공통모드 노이즈 감쇠를, 누설 인덕턴스로부터 차동모드 노이즈 감쇠를 기대할 수 있다. 이때, 누설인덕턴스가 너무 클 경우 차동모드 노이즈 감쇠에는 우수하지만, 전기/전자제품이 슬림화됨에 따라 공통모드 초크의 누설 자속과 전원공급기를 덮고 있는 금속덮개 사이에 자계 간섭에 의한 진동/소음문제가 발생될 수 있다. 본 논문에서는 누설자속을 조절할 수 있는 공통모드 초크의 코어형상 및 권선기법을 제안한다. 제안된 방법은 진동 및 소음을 제어할 수 있는 장점을 지니고 있다.

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