• Proceedings of the KIPE Conference
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• 2010.11a
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• pp.288-289
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• 2010

다양한 신재생에너지의 발전원 확보를 위해서는 발전원의 출력 안정화가 필수적으로 수반되어져야 한다. 본 논문은 다양한 신재생에너지 발전원의 안정화를 위한 핵심기기 중 하나인 STATCOM의 설계 및 제작에 관한 내용이다. 개발 진행 중인 1MVA STATCOM은 제주도 행원 풍력발전의 전력품질을 개선하기 위해 설치될 예정으로 3-Level 인버터로 구성된 Stack과 LC 필터 그리고 변압기와 수배전반으로 구성되어 있다.

• IMMUNE NETWORK
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• v.3 no.2
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• pp.145-149
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• 2003

Background: Apoptosis has been implicated in pathogenesis of various disease. Apo-1/Fas (CD95) is one of the main pathway of apoptosis. To examine the possible relationship between Apo-1/Fas (CD95) and primary knee osteoarthritis, MvaI restriction length polymorphism (RFLP) in human Apo-1/Fas (CD95) gene was assessed. Methods: Genotype and allele frequencies in promoter region in the Apo-1/Fas (CD95) gene were studied by PCR-RFLP in 226 Korean controls and 148 Korean patients with primary knee osteoarthritis. Results: No statistically significant difference in the genotypic distribution and allelic frequencies was found between the control and the knee oateoarthritis patients. But in the severe grade (grade 3, 4) Kellgren-Lawrence score patients, the frequency of $MvaI^*1$ (G) allele was significantly decreased (P=0.0392) and the of $MvaI^*2$ (A) allele frequency was significantly increased (P=0.0473) compared to the normal controls. Conclusion: Apo-1/Fas (CD95) gene polymorphism is a part a determinant factor of severity in knee osteoarthritis, the patients with $MvaI^*2$ (A) allele is more severe radiologic progression. Further substantiation studies are needed in larger patient samples and various other apoptosis related genes to elucidate the mechanism of osteoarthritis, including the Fas ligand gene analysis.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.4
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• pp.177-184
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• 2010

This paper presents the electric field analysis for 2[MVA] mold transformer using finite element method. The electric field was calculated for the voltage applied to the mold transformer without voids in the insulating material. Then, it was analysed the maximum electric field when the voids was in the insulating materials. And the starting voltage of partial discharge was predicted due to the voids. The effects of voids in epoxy resin on the electric field were investigated for different sizes, shapes, positions and arrangements of voids.

• 한국초전도학회:학술대회논문집
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• v.13
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• pp.91-91
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• 2003

• 한국초전도학회:학술대회논문집
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• v.14
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• pp.85-85
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• 2004

• 한국초전도학회:학술대회논문집
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• v.12
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• pp.73-73
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• 2002

• The Transactions of the Korean Institute of Power Electronics
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• v.6 no.2
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• pp.125-131
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• 2001

This paper presents a application of vector control strategy to 1.2MVA traction drive for railway vehicle. The vector control required the control of the phase and amplitude of output voltage vector. But in case of traction system for railway vehicle, the one-pulse mode is used at high speed region in order to utilize the link voltage fully. So it is impossible to control the flux and torque axis current instantaneously and independently in the region. So this paper proposes a mixed control algorithm, where the vector control strategy at low speed region and slip-frequency control strategy at high speed region is used. And precise switching technique between the two different control strategy is proposed. The proposed strategy is verified by experimental results with a 1.2MVA traction drive system with four 210kW induction motors.

• 전기의세계
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• v.28 no.2
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• pp.14-22
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• 1979

전력계통의 증대에 따라 변전소용 변압기도 대용량화되어 가고 있다. 변전소용 대용량 변압기의 경우 최대문제가 되는 것은 철도운송의 경우 운송한계에 있다. 일본의 철도는 협궤이기 때문에 운송능력이 작고 275KV 변압기의 경우 조립운송할 수 있는 한계용량은 종래 300MVA라고 되어 왔지만, 최근 기술의 진보와 신뢰성 향상 시책에 따라 450MVA까지도 철도운송을 하는 것이 가능케 되었다. 이와같은 사정때문에 당사는 이번에 중부 전력.북풍전변전소에 3상 60Hz, 275/15 4/31.5KV, 450/450/135MVA 변압기를 납품하였다. 본기는 초고압 변전소용으로는 일본에서 최대급의 것으로 여러가지의 특징을 가지고 있다. 그 주요점을 들면, (1) 철도에 의한 조립운송을 가능케 했다. 더우기 부하시 TAP 절환기를 본체 TANK에 조립해서 운통한다. (2) 일차 초고압 권선에는 선로단을 중앙에 배치한 HISERCAP 권선을 채용한다. (3) 당초 65Phon, 장래 55Phon의 저소음사양을 만족시키기 위해서 고효율의 송유풍냉식 저소음방열관을 사용했다. (4) 기기의 신뢰성을 높이기 위해 설계, 제조, 시험 검사 각면에 만전을 기했다. 그러나 그외에도 여러가지 연구가 추진되고 있으며 다음에 개요를 설명하고져 한다.

• Proceedings of the KIPE Conference
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• 2004.07b
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• pp.774-777
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• 2004

한국전력공사에서는 전압원 인버터형 FACTS 기기인 UPFC를 전남 강진군 강진변전소에 설치 (2003. 5. 23준공) 운전하였다. 강진 UPFC는 한전과 (주)효성이 공동으로 투자하고, 지멘스와의 기술제휴를 통해 개발하였으며, 40MVA 병렬인버터, 40MVA 직렬인버터로 구성되어 총 80MVA 용량이다. 현재 병렬인버터는 강진 모선전압 제어, 직렬 인버터는 강진-장흥간의 조류제어에 기여하며, 상용운전 중이다. 본 논문에서는 강진 UPFC 준공 1년여를 맞이하여, 그 동안에 발생한 이벤트 및 운전실적을 분석하였다.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.943-945
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• 2002

This paper presents conceptual design and 3-D electromagnetic analysis of 1MVA transformer with BSCCO-2223 High Tc Superconducting (HTS) tapes. The rated voltages of each sides of the transformer are 22.9 kV and 6.6 kV, and double pancake windings were adopted. High voltage and Low voltage sides were composed of several double pancake windings. Four HTS tapes were wound in parallel for the windings of low voltage side and were transposed in order to distribute the currents equally in each conductor. The transformer core was designed as a shell type core made of laminated silicon steel plates and the core is separated with the windings by a cryostat with Fiberglass Reinforced Plastics(FRP). A sub-cooling system using $LN_2$ were designed to maintain the coolant temperature of 65K. Finally perpendicular components of magnetic field applied to tapes were calculated 0.24T in the rated operation using 3-D analysis. A real 1MVA HTS transformer will be manufactured in near future based on the design parameters presented in this paper.