• 한국산학기술학회논문지
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• 제21권1호
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• pp.277-283
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• 2020

기계식 기어의 치를 영구자석으로 대체한 동심 마그네틱 기어에서 원주방향을 따라 놓인 모든 자석이 동력 전달에 관여하므로 감속비를 결정하는 자석의 극수비는 마그네틱 기어의 거동 특성에 큰 영향을 미친다. 본 논문에서는 극수비를 변화시켜가며 마그네틱 기어에서 생성되는 전달토크의 밀도, 동손을 고려한 토크의 효율, 코깅 특성을 포함한 토크의 품질 등을 유한요소 해석을 이용하여 비교 분석하였다. 구동측의 극수를 2극에서 5극까지 변화시킬 때 전달토크가 최대가 되는 최적의 극수비가 존재함을 확인하였으며 이는 모듈레이터를 통한 구동측 자기장의 필터링 성분에 직접적인 영향을 받다. 전달 효율 역시 와전류 생성 밀도와 자기장간에 비례특성이 있으므로 전달 토크 밀도와 유사한 경향을 나타내는 것을 알 수 있으며 낮은 기어비에서는 95% 이상의 효율을 보인다. 제한된 극수를 갖는 영구자석의 상호작용에 기인하는 코깅 특성은 일반적인 동기 모터에서와 같이 구동측 자석의 개수와 모듈레이터 치의 개수간의 최소공배수에 반비례하는 것을 확인할 수 있었다. 전달 토크 평가를 위해 실제 시험 모델이 제작되었고 실증시험이 진행되었다.

• Journal of Power Electronics
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• 제11권4호
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• pp.408-417
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• 2011

The plug-in hybrid electric vehicles (PHEVs) are specialized hybrid electric vehicles that have the potential to obtain enough energy for average daily commuting from batteries. The PHEV battery would be recharged from the power grid at home or at work and would thus allow for a reduction in the overall fuel consumption. This paper proposes an integrated power electronics interface for PHEVs, which consists of a novel Eight-Switch Inverter (ESI) and an interleaved DC/DC converter, in order to reduce the cost, the mass and the size of the power electronics unit (PEU) with high performance at any operating mode. In the proposed configuration, a novel Eight-Switch Inverter (ESI) is able to function as a bidirectional single-phase AC/DC battery charger/ vehicle to grid (V2G) and to transfer electrical energy between the DC-link (connected to the battery) and the electric traction system as DC/AC inverter. In addition, a bidirectional-interleaved DC/DC converter with dual-loop controller is proposed for interfacing the ESI to a low-voltage battery pack in order to minimize the ripple of the battery current and to improve the efficiency of the DC system with lower inductor size. To validate the performance of the proposed configuration, the indirect field-oriented control (IFOC) based on particle swarm optimization (PSO) is proposed to optimize the efficiency of the AC drive system in PHEVs. The maximum efficiency of the motor is obtained by the evaluation of optimal rotor flux at any operating point, where the PSO is applied to evaluate the optimal flux. Moreover, an improved AC/DC controller based Proportional-Resonant Control (PRC) is proposed in order to reduce the THD of the input current in charger/V2G modes. The proposed configuration is analyzed and its performance is validated using simulated results obtained in MATLAB/ SIMULINK. Furthermore, it is experimentally validated with results obtained from the prototypes that have been developed and built in the laboratory based on TMS320F2808 DSP.

• 패션비즈니스
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• 제14권4호
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• pp.91-101
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• 2010

This paper has the purpose of suggesting a development-method on the fashion products that would secure the competitiveness in the global markets through creating supersensitive practical products on the basis of developing originative fashion-goods being made of jacquard that is fine quality of couture. This paper has collected data through the cases of the developed nations in fashion, precedent studies and all the related literature on the subject. The results of this researching are as following: The first, it is expected that the necessity of developing new fashion products would be appealed toward the prestige group of consumers who are seeking for the fine quality and super-sensitivity in female fashion in Korea, and it is the current situation that the products made of jacquard are gradually expanding not only in the area of apparel, fashion goods and interior but also another areas. The current situation of the global market suggests the necessary strategy of survival, that is, the development of supersensitive materials and creative products which would be able to keep the high quality and lower the selling price through cost reduction. The second, the suggestion of the direction in developing the products of the female fashion made of jacquard has two points - the development of the texture that would realize a unique form and the development of the material that would be able to realize planar pattern and three dimensional pattern which are woven with thin and light materials with various solidity and delicacy through various techniques of mixing and three dimensional expression. The third, the expected ripple effect and utilization generated from the development of fashion products are as followings: As material characteristics of jacquard, It needs the specialization of various techniques and specialized production system in using jacquard, and the specialized technique and system would make it possible to produce not only the higher value-added products through expressing affluent colors and delicate design but also competitive products through cutting the process and cost, eventually, it would lead to the expansion of the jacquard market of super-sensitive prestige. Therefore, it is remarkable that various development of products toward the global market and the prestige female fashion market can suggest the vision that make the national fashion industry develop into the higher value-added knowledge industry integrating technology and culture.