• 제목/요약/키워드: electromagnetic method

검색결과 3,262건 처리시간 0.033초

전자파의 집중도를 이용한 바이모달 트램의 전자파 차폐 성능 분석 (Analysis of Electromagnetic Shielding Performance for a BiMODAL Tram using an Electromagnetic Concentration Index)

  • 최낙선;정기우;김남경;송명곤;이강원;목재균;김동훈
    • 전기학회논문지
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    • 제60권7호
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    • pp.1378-1384
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    • 2011
  • In this paper, the electromagnetic shielding performance of a BiMODAL Tram is investigated by means of an electromagnetic analysis tool, called HFSS. For the purposed of doing this, first, three-dimensional finite element modeling for the tram including electronic devices and engine room is carried out. Then, for quantitatively assessing the electromagnetic shielding performance of the tram's body, concentration indexes for electric field magnitude and time-average stored electric energy are introduced. From numerical results, it is inferred that the tram's body can protect the electronic devices and engine room against external electromagnetic waves from 30 MHz to 100 MHz.

A Finite-element Method Analysis of Electromagnetic Noise Absorption in a Coplanar Transmission Line Integrated with a Magnetic Film

  • Sohn, Jae-Cheon;Han, Suk-Hee;Lim, Sang-Ho
    • Journal of Magnetics
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    • 제11권2호
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    • pp.90-94
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    • 2006
  • A finite-element method is used to analyze loss generation and electromagnetic noise absorption characteristics of a coplanar waveguide transmission line integrated with a magnetic thin film. Parameters used in the analysis are the electrical resistivity of the magnetic layer and the thickness of both magnetic and insulating layers. The results indicate that L-C resonance is the main loss mechanism of the electromagnetic noise absorption.

TEM CELL에서의 전자장 수치해석 (Numerical Analysis of Electromagnetic Fields in TEM Cells)

  • 이애경;이상회;김정기
    • 한국전자파학회지:전자파기술
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    • 제2권1호
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    • pp.37-45
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    • 1991
  • The electromagnetic field distribution within rectangular coaxial transmission lines (RCTL:TEM cells) is calculated using a numerical method. Boundary integral equations(BIE) considering equivalence theorem and extended boundary condition(EBC) in tapered region are used, thereby restricting the operational frequencies (0~130 MHz) below the cell cutoff frequency(130 MHz). The EM fields within NIST TEM cell ($1\times0.6\times2m$) are calculated by this method. The results of the numerical calcuation have a good agreement in the cross-sectional EM field distribution of TEM cell with 2-dimensional analysis results. Based on this method, the first cutoff freque- ncy in high order modes in the cell and the electric field polarization are considered.

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Time Domain법에 의한 전파흡수체의 흡수능 측정법의 비교연구 (A Comparative Study on Measuring Methods of Absorption Characteristics for Electromagnetic Wave Absorber Using Time Domain Method)

  • 김동일;김상태;박지용;정세모
    • 한국전자파학회지:전자파기술
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    • 제6권2호
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    • pp.11-18
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    • 1995
  • 본 연구는 평판형, 그리드형, 특수형상 등의 페라이트 전파흡스체의 흡수능 측정시스템을 구축하는 데에 목적이 있다. 그러나 30MHz와 같이 낮은 주파수에서 흡수능을 측정하느 것은 대단히 곤란 . 이와같은 문제를 해결하기 위하여 평행평판 스 라인을 사용하여 정재파측정법 및 시간영역법을 제안하였으며, 실제 측정시스템을 구성하요 제안한 측정볍으로 그리드형 페라이트 전자파흡수체의 특성을 측정. 평가하였다.특성을 측정. 평가하였다.

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힘의 방향성을 고려한 전자기 커플러의 위상 최적화 (Topology Optimization of an Electromagnetic Coupler Considering Force Direction)

  • 양승진;유정훈
    • 정보저장시스템학회논문집
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    • 제2권4호
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    • pp.230-235
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    • 2006
  • The machine locking system is an important device for the safety of persons using the machine. In this study, a locking system using electromagnetic fields is proposed to decrease the defects and the cost for repairing and maintenance of the existing locking system using structural mechanism. We analyze the electromagnetic locking system and calculate the generated force considering direction by the finite element method. Also, we set up two design domains for the topology optimization; first domain is optimized to reduce the volume and the other is optimized to maximize the generated force keeping the volume, especially. The optimal design is obtained by integration of the two optimized results. An improved design is obtained by the optimal topology and it is confirmed by comparison with the initial locking system.

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Calculation of Electromagnetic Excitation Forces in Double Skewed Motors

  • Bao, Xiaohua;Di, Chong;Zhou, Yang
    • Journal of Electrical Engineering and Technology
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    • 제13권2호
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    • pp.812-821
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    • 2018
  • An electromagnetic excitation force is caused by the air-gap flux density, which greatly influences the noise and vibration of the motor. In many real projects, skewed slot technology is widely used to reduce the harmonic components of the air-gap flux density to reduce the noise and vibration of the motor. However, a skewed slot has several side effects such as a transverse current and axial drifting. Thus, a double skewed slot rotor is selected with the aim of eliminating these side effects. This paper presents the exact structure of the double skewed slot rotor and the mechanism whereby the electromagnetic excitation force can be reduced. A multi-slice method is adopted to model the special structure. Finite element simulation is used to verify the theory.

통합설계방법을 적용한 가동자석형 3축 액추에이터의 설계 (Design of 3-Axis Moving Magnet Type Electromagnetic Actuator using Integrated Design Method)

  • 김상용;박노철;박영필;박경수
    • 정보저장시스템학회논문집
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    • 제7권2호
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    • pp.80-84
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    • 2011
  • In this paper, we propose the integrated design method that enables multi-physics modeling and coupled-field analysis by connecting an electromagnetic field and a structural field. We design the 3-axis moving magnet type actuator that has the high structural stiffness and the effective electromagnetic circuit generating large electromagnetic force. Through design of experiments (DOE) and optimization, the designed actuator is optimized and satisfies high dynamic characteristics over the desired specifications.

FDTD를 이용한 격자형 페라이트 전파흡수체 특성 해석 (FDTD Analysis of the Absorption Characteristics for Grid Ferrite Electromagnetic Wave Absorber)

  • 이재용;정연춘;명노훈
    • 한국전자파학회논문지
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    • 제9권4호
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    • pp.483-490
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    • 1998
  • The reflectivity of a grid ferrite electromagnetic wave absorber is analyzed using finite difference time domain (FDTD) method, which is usually used in anechoic chambers for EMI / EMS test. The frequency dispersive characteristics of ferrite medium and its boundary condition are modeled using magnetic flux in addition to E- and H-fields. By applying Floquets theorem, FDTD analysis of the grid ferrite absorber with periodic infinite array is simplified as a unit cell problem. The method of homogenization which is mainly utilized in the calculation of absorber reflectivity as a low frequency technique takes only into account volume fraction of the unit cell of the absorber except for the structure of medium geometry. However, the presented method in this paper can analyze the geometry effect of the unit cell with its medium characteristics up to high frequency region.

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광선 추적법을 이용한 우주 환경에서의 안테나 전파 특성 예측 (Prediction of Antenna Propagation Characteristic in Space Environment Using Ray Tracing Method)

  • 김창성;박용배
    • 한국전자파학회논문지
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    • 제27권11호
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    • pp.1023-1026
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    • 2016
  • 우주 환경에서의 굴절률 변화를 고려하여 안테나의 전파 특성을 계산한다. 대류권, 성층권, 전리권의 유효 굴절률을 계산하고, 대기권을 통과하면서 굴절되고 감쇠되는 전파 특성을 계산하기 위해 광선 추적법, 기하광학법, 호이겐스의 원리를 이용한다.

솔레노이드형 전자펌프의 전자력 해석 (Electromagnetic force analysis of electromagnetic pump)

  • 정용화;안창희;김동희;김한
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1995년도 하계학술대회 논문집 A
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    • pp.80-82
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    • 1995
  • The electromagnetic force of magnetic plunger for electromagnetic pump system are calculated by finite element method which consider the eddy current, the plunger motion. The mechanical motion equation are solved Rune-Kutta method, and coupled with the finite element method. With the external circuit equation dynamic simulation of the pump system are achieved. Electrostatic flux is verified by comparing with other commercial analysis software. Similar analysis of other type solenoidal actuators can be done by this procedure.

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