• 한국전자파학회지:전자파기술
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• 제5권4호
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• pp.64-70
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• 1994

전력주파수 자기장 , 펄수 자기장 및 감쇠진동 자기장 내성평가에 대한 규격이 국제전기기술위원회(IEC)에 서 재정되어 전기.전자제품들의 자기장내성에 대한평가가 이루어질 전망이다. 이를 위해 본 연구에서는 IEC규격에서 정하고있는 자기장 내성평가용 유도코일인 정사각형 코일$1m\times1m$, 직사각형 코일 $1m\times2.6m$와 코일사이의 간격이 0.8m 및 0.6m인 이중 정사각형 코일 $1m\times1m$에 대한 자기장의 세기 및 균일도를 계산하여 IEC규격에서 규정한 유도코일의 유호 시험평가 영역을 도출하였다.

• Journal of Magnetics
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• 제2권1호
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• pp.12-15
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• 1997

Fe-(3∼6.5wt%) Si alloy powders having a high magnetic induction(Bs) and a low core loss value for high frequency use were obtained by an extractive melt spinning as well as a centrifugal atomization technique. Sintered core rings made by the rapidly solidified Fe-6.5wt% Si powders exhibited the high frequency magnetic properties : megnetic induction(B8) of 1.23 T, coercivity(Hc) of 0.12 Oe, relative permeability(${\mu}$a) of 6321, and core loss(W10/50) of 1.27 W/kg from the rings of 1.1 mm thick. The magnetic induction values were found to be almost identical to those of non-oriented Fe-6.5wt% Si steel sheet and double the value of 6.5wt% Si sheet prepared by the CVD technique. The high frequency core losses(W) up to 10 kHz(W10/10k) were measured to be competitive to those of grain-oriented Fe-6.5wt% Si steel sheet.

• 조명전기설비학회논문지
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• 제23권9호
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• pp.62-66
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• 2009

3개의 자속에 대한 유도전동기의 입력을 계산한 후 3점을 2차 보간하여 2차 함수를 만들고, 입력이 최소가 되는 새로운 자속을 구한 후, 이 자속을 이용하여 다시 2차 보간하여 입력이 최소가 되는 자속을 구하는데, 새로운 점을 사용한 2차 보간을 수렴조건을 만족할 때까지 반복해서 입력이 최소가 되는 자속을 구하는 방법을 제안한다. 시뮬레이션 결과 최대효율제어를 위한 자속으로 신속한 수렴이 가능함을 보인다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.923-925
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• 2008

As known generally, when permanent magnets whose poles are upward and downward in order, arranged into the circumferential direction rotate under the conducting plate, the rotating force acts on the plate as well as the repulsive force. If the magnetic field by the magnet wheel(the above rotating permanent magnets) is partially shielded, the magnet wheel over open region can be a linear induction motor. The distinct feature from induction motor is that the traveling magnet field is produced by the moving permanent magnet instead of ac current. Furthermore, a variation of the open region changes the direction of the thrust force. In this paper, we introduce a concept of the linear actuator using the magnet wheel. Under the above shielding condition, a few simulation results and its verification from a simple test setup are described.

• 조명전기설비학회논문지
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• 제22권5호
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• pp.58-63
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• 2008

유도전동기 고정자자속 기준제어의 최대효율제어를 위한 초기자속 값의 계산방법을 제안한다. 3개의 자속에 대한 입력을 계산한 후 3점을 2차 보간하여 2차 함수의 최소점, 즉 입력이 최소가 되는 자속을 구하고, 이 자속을 초기 값으로 하여 최대효율제어를 수행한다. 시뮬레이션 결과 기존의 방법에 비해서 제안한 방법에 의하여 최대효율점으로의 수렴시간이 단축됨을 보인다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2008년 영문 학술대회
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• pp.602-605
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• 2008

The anode sheath structure in the hollow anode of an anode-layer type Hall thruster was numerically computed using a fully kinetic 2D3V Particle-in-Cell and Direct Simulation Monte Carlo(PIC-DSMC) code. By treating both ions and electrons as particles, anode surface region, which is electrically non-neutral, was analyzed. In order to analyze in detail, the calculation code was parallelized using Message Passing Interface (MPI). The code successfully simulated the discharge current oscillation. In the low magnetic induction case, ion sheath appears in the anode surface because ionization is enough to maintain the plasma occurs in the anode hollow. As the magnetic induction increases, main ionization region move to outside of the anode. At the same time, anode sheath voltage decreases. In the high magnetic induction case, electron sheath appears on the anode surface periodically because the ionization occurs mainly in the discharge channel. This anode sheath condition shift can be explained using the simple sheath model.

• Journal of Magnetics
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• 제18권1호
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• pp.9-13
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• 2013

Shielding effects in conductive and magnetic materials were investigated as a function of properties, thickness and diameter. In this work, evaluations on passive conductive and magnetic shield specimens were achieved through experimentation set-up using 50 Hz single and three phase induction field sources. Analysis on material microstructure properties and characteristics of shielding specimens were performed with the use of vibrating sample magnetometer (VSM) and field emission scanning electron microscopy (FESEM). An induction field at $136{\mu}T$ of single phase system and $50{\mu}T$ of three phase systems were observed to the shield specimens with the thickness ranged of 0.2 mm to 0.4 mm. It is observed that shield specimen efficiency becomes inversely proportionate to the increment of induction fields. The decrease was attributed to the surface structure texture which relates to the crystallization and non-crystallization geometrical effects.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1989년도 하계종합학술대회 논문집
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• pp.24-27
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• 1989

In the case of analyzing electric machinery by finite element method, so far, magnetic current was selected as a driving source. But terminal voltage is a driving source in real systems, and magnetic current is varied according to variation of load conditions. Therfore, in this paper magnetic flux distribution of linear induction motor was analized by using kirchhoff's second law with voltage as a driving source, and magnetic current was calculated.

• 한국산업안전학회:학술대회논문집
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• 한국안전학회 1998년도 추계 학술논문발표회 논문집
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• pp.29-39
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• 1998

It is well known for 410L ferritic stainless steel powder to applicate a sensor ring in anti-lock brake system of automobile, several studies, because of its excellent magnetic properties. This study was carried out In investigate the magnetic properties such as the maximum magnetic induction, coercivity and maximum permeability of the materials with functions of sintering density! time and temperature, and concluded as follows； 1. Sintering under the circumstances of hydrogen gas and tile temperature of $1250^{\circ}C$ for 60min. showed that nitrogen was increased, whereas carbon and oxygen decreased in quantities. 2. Both maximum magnetic induction value of 4700Gauss and permeability of 200 were obtained at the maximum sintering density of 6.89g/$cm^3$. Here, the properties showed a linear increasement with increasing the sintering density. 3. Coercivity sharply increased with incresing the sintering density and reached to 7.6Oe at the maximum sintering density of 6.89g/$cm^3$.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 A
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• pp.157-159
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• 1996

For the optimal design of the induction heating cooker, precise and accurate analysis of the magnetic field inside the jar must be achieved first. Until now, design methods based on experience has been used in industry field. But this takes a lot of trial and error, high cost and also long development time. So the analysis of the magnetic field distribution is very important. In this paper the magnetic field inside the induction heating cooker is analyzed by using axisymmetrical FEM(finite element method). And the method of the coil location design for the optimal heat source distribution using sensitivity analysis is developed. In addition, the shielding effect of the non-axisymmetrical 3-D ferrite structure used in induction heating cooker is also analyzed by the integral method.