• 전산구조공학
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• 제4권2호
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• pp.103-110
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• 1991

컴퓨터의 제한된 코어메모리로 대형문제를 해결하기 위하여 디스크를 마치 메모리처럼 사용할 수 있는 가상 메모리 데이타베이스 기법을 개발하였다. 이 기법과 아울러 최대 가용코어메모리를 작동시키는 방식을 사용하여 유한요소 해석시 흔히 발생하는 스카이라인 형태로 저장된 대칭통산행예(Sparse Symmetric Matrix)에 대한 매우 효과적인 코어 내 및 코어 외 직립방정식의 해법을 개발하였다. 제안된 방법은 다른 코어 외 해법에 비해 알고리즘 및 코딩이 매우 간단하여 계산효율을 상당히 향상시켰다. 해석예에서는 제안된 방법을 사용하여 대규모 구조해석 문제를 메모리 용량이 작은 소형컴퓨터에서 대단히 효율적으로 해결하였음을 보여주었다.

• Journal of international Conference on Electrical Machines and Systems
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• 제3권4호
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• pp.379-382
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• 2014

In this paper, the cogging torques were calculated for 1kw double-sided axial flux permanent magnet (AFPM) generator with different stator core pole arrangements. The generator is composed of 18 stator pole and 24 rotating field magnets on each side. The cogging torques of the generator with three types of arrangements of stator poles were calculated using 3D finite element method and the optimum core shape was determined to minimize the cogging torque.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.812-813
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• 2011

This paper presents the characteristic of newly developed electrical steel and motor performance analysis for HEV/EV. This material is developed and optimized for high frequency operation to reduce the core losses in traction motors to increase fuel efficiency. Four types of electrical steel are introduced, which are optimized for high flux density (PNHF), high frequency low core loss (PNF), high punchability (PNS) and high strength (PNT) to meet different specifications from different types of traction motors. To identify the motor performance with this material, finite element analysis was used to calculate core loss as well as Ld and Lq for efficiency map. Also structure analysis was performed to calculate stress on bridge rotor.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.1210-1211
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• 2011

The inherent drawback of iron-core type permanent magnet linear synchronous motor (PMLSM) is detent force that is dependent on several major factors such as PM length, slot clearance, and skewing. To minimize the detent force, this paper proposes a structure optimization using the combination computation of two dimensional (2-D) finite element analysis (FEA) and response surface methodology (RSM). The RSM, that is a collection of the statistical and mathematical techniques, is utilized to predict the global optimal solution based on the FEA calculated results of the detect forces for different combinations of factors. With the help of the combination computation the high capacity iron-core type PMLSM with more than 12000 N propulsion forces only contains less than 3 N detent forces.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2000년도 춘계학술대회 논문집
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• pp.89-94
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• 2000

Because the structural elements used in the automobile, astronautic and ship industries are put in dynamic loading environments, much interest is given to the damping of the structural elements, as well as high flexural rigidity and strength per density. Therefore, in this study, the structural damping value of the aluminum honeycomb sandwich plate(AHCP) has been experimentally extracted, and directly applied to the finite element, for the dynamic analysis of the plate considering the structural damping. The analysis results of this theory was compared with the results of the actual modal analysis method. It was observable that the two analyses concurred, establishing the structural damping and analysis method of the AHSP.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집A
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• pp.93-98
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• 2001

Fatigue strength evaluation was carried out for the core support structure of a low voltage circuit breaker. The impact load acting on the core support was calculated based on the strains measured during operation. A three-dimensional finite element analysis was performed to determine local peak stresses for fatigue evaluation. Fatigue safety factors were calculated using the modified Goodman, Gerber, Soderberg, and modified Findley lines, considering the magnitude of the residual stress and impact load.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 추계학술대회논문초록집
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• pp.401.1-401
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• 2002

The state core of a motor/generator was modeled using dynamic model updating technique based on the modal testing work. In order to take into account the orthotropic effect of laminated structure the axial, radial and circumferential properties of the solid element were separately varied to match the primary modes of the stator core which were extracted from the modal testing. Comparison of the results after model tuning showed fairly good coincidence with measured data.

• Steel and Composite Structures
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• 제1권3호
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• pp.341-354
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• 2001

This paper provides a state-of-the-art review on advanced analysis models for investigating the load-displacement and ultimate load behaviour of steel and composite frames subjected to static gravity and lateral loads. Various inelastic analysis models for steel and composite members are reviewed. Composite beams under positive and negative moments are analysed using a moment-curvature relationship which captures the effects of concrete cracking and steel yielding along the members length. Beam-to-column connections are modeled using rotational spring. Building core walls are modeled using thin-walled element. Finally, the nonlinear behaviour of a complete multi-storey building frame consisting of a centre core-wall and the perimeter frames for lateral-load resistance is investigated. The performance of the total building system is evaluated in term of its serviceability and ultimate limit states.

• Journal of international Conference on Electrical Machines and Systems
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• 제2권1호
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• pp.16-22
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• 2013

This paper presents the analysis and optimization of air-core permanent magnet linear synchronous motor with overlapping concentrated windings to achieve high thrust density, high thrust per copper losses and low thrust ripple. For the motor design, we adopt equivalent magnetizing current (EMC) method to analyze the magnetic field and give analytical formulae for calculation of motor parameters such as no-load back EMF, dynamic force, thrust density and thrust per copper losses. Further, we proposed a multi-objective optimization by genetic algorithm to search for the optimum parameters. The design optimization is verified by 2-D Finite Element analysis (FEA).

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.86-88
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• 2004

In this paper, optimal stator slot shape of 3-phase inverter-fed induction motor is designed to reduce stator core and winding losses. For the analysis, the F.E.M on 1 phase band periodic condition in stator is coupled with harmonic equivalent circuit. For the optimal design, the conjugate gradient method is used as an optimizing algorithm. The stator core and winding losses are reduced by the design method. The results are verified by those of the time-step finite element analysis.