CURRENT STATUS OF NUCLEAR FUSION ENERGY RESEARCH IN KOREA

MYEUN KWON,YOUNG SOON BAE,SEUNGYON CHO,최원호,홍봉근,황용석,JIN YONG KIM,KEEMAN KIM,YAUNG-SOO KIM,JONG-GU KWAK,HYEON GON LEE,SANGIL LEE1,나용수,BYUNG-HOON OH,YEONG-KOOK OH,박지연,HYUNG LYEOL YANG,IN KEUN YU 한국원자력학회 2009 Nuclear Engineering and Technology Vol.41 No.4

The history of nuclear fusion research in Korea is rather short compared to that of advanced countries. However, since the mid- 1990s, at which time the construction of KSTAR was about to commence, fusion research in Korea has been actively carried out in a wide range of areas, from basic plasma physics to fusion reactor design. The flourishing of fusion research partly owes to the fact that industrial technologies in Korea including those related to the nuclear field have been fully matured, with their quality being highly ranked in the world. Successive pivotal programs such as KSTAR and ITER have provided diverse opportunities to address new scientific and technological problems in fusion as well as to draw young researchers into related fields. The frame of the Korean nuclear fusion program is now changing from a small laboratory scale to a large national agenda. Coordinated strategies from different views and a holistic approach are necessary in order to achieve optimal efficiency and effectiveness. Upon this background, the present paper reflects upon the road taken to arrive at this point and looks ahead at the coming future in nuclear fusion research activities in Korea.

기관지폐포성세포암에 동반된 호산구증다증 1례

권경순,이영현,정재천,김종설,강면식 영남대학교 의과대학 1987 Yeungnam University Journal of Medicine Vol.4 No.1

저자들은 61세 남자환자에서 호산구증다증을 동반한 폐의 기관지폐포성세포암 1예를 경험하였고 문헌고찰도 함께 하였다. The solid and hematoiogic cancer are occasionally accompained by peripheral blood eosinophilia and suggest tumor necorsis or wide dissemination, but the mechanisms underlying this curious relationship remain obscure. The association of this eosinophilic leukemioid reaction with carcinoma seems to occur must frequently with bronchogenic carcinoma. Several mechanisms for this association were considered: eosinophil chemotactic factor, eosinophilia mediated by T-lymphocyte, and eosinopoietic hormone. we are here reporting a case of bronchoalveolar cell carcinoma of lung associated with peripheral eosinophilia in a 60-year-old male patient.

세사를 사용한 콘크리트의 역학적 특성 평가

구면수(Koo, Myeun Su),배수호(Bae, Su Ho),권순오(Kwon, Soon Oh),이현진(Lee, Hyun jin),이승한(Lee, Seung Han) 한국콘크리트학회 2013 한국콘크리트학회 학술대회 논문집 Vol.2013 No.10

KSTAR Charge Exchange Spectroscopy System

Won-Ha Ko,Seungtae Oh,Myeun Kwon IEEE 2010 IEEE transactions on plasma science Vol.38 No.4

<P>The charge exchange spectroscopy (CES) system for the Korea Superconducting Tokamak Advanced Research (KSTAR) device is designed to obtain profiles of the ion temperature and rotation velocity by using modulated neutral beam injection and a background system. The CES diagnostic will measure the ion temperature of carbon and other impurities, in conjunction with the neutral heating beam in KSTAR. The visible light from the plasma will be concentrated via collection optics, assembled, and imaged onto quartz fibers. We show the progress of the KSTAR CES diagnostic including the collection assembly, lens design, and cassette system. The KSTAR CES system utilizes a 1.33-m Czerny-Turner spectrometer with variable wavelength. The detector is a thinned back-illuminated charge-coupled device (CCD) that has high quantum efficiency and high readout speed. The spectrometer and CCD detector that will be used in the KSTAR CES system have been tested. Two CES diagnostics systems for KSTAR are compared.</P>

Fusion Licensing and Safety Studies in Korea

Hyuck Jong Kim,Hyung Chan Kim,Myeun Kwon,Gyunyoung Heo,In-Ju Hwang,Soon Heung Chang,Jong Kyung Kim,Yong Su Kim IEEE 2014 IEEE transactions on plasma science Vol.42 No.3

<P>Korean activities on fusion licensing and safety studies have been going through three phases. The first phase started with the licensing of the Korean Superconductor Tokamak Advanced Research (KSTAR) classified as a radiation-generating device on the basis of the existing nuclear regulations. To accommodate the specific characteristics of a tokamak device that is to use deuterium in fusion plasma physics studies, a set of instructions to examine the safety of KSTAR and to approve an operating permit were developed and issued by the regulatory body, Korean Institute of Nuclear Safety. The second phase is being investigated for the International Thermonuclear Experimental Reactor (ITER). To verify the design of the test blanket module that will be installed and tested in the ITER, safety studies were carried out using the experimental results and computational codes. To minimize occupational irradiation damages, a study on the tritium behaviors is being carried out as Korea will provide a part of the tritium systems of ITER. The last phase has initiated to recognize significant safety issues and to support future licensing process for a fusion DEMO plant. Relevant studies are being carried out in collaboration with the academies funded by the National Fusion Research Institute of Korea. These front-end studies include the conceptual analysis on the safety and radiological consequences, preliminary studies on the layout of research, and on the future regulatory requirements of the fusion DEMO plant. This paper summarizes these activities on fusion safety with the findings of the front-end studies to date. It also proposes a pathway for the novel licensing process of a fusion DEMO plant with the tokamak concept.</P>

Experimental Evaluation of Inductance and Its Impact on Quench Detection of the KSTAR Coils

Yonekawa, H,Yong Chu,Young-ok Kim,Kaprai Park,Hoon-Kyun Na,Myeun Kwon IEEE 2011 IEEE transactions on applied superconductivity Vol.21 No.3

<P>Windings of Nb<SUB>3</SUB>Sn cable-in-conduit conductors of the toroidal field (TF) and the 1st-5th poloidal field (PF) coils of the Korea Superconducting Tokamak Advanced Research (KSTAR) have Incoloy-908 jackets, which exhibit weak ferromagnetism. The inductance of the PF coils was measured by monitoring the induced voltages on the coils while TF coils were steadily energized at 20 kA, and one of each pair of PF coils was charged up to 4 kA at 2 kA/s. At a large PF current, the measured self inductance was very close to the design value. In contrast, the measured self inductances of the PF1-PF5 coils increased 90-135% by decreasing their current below 2 kA; whereas those of the PF6-PF7 coils almost stayed at the same levels. On the other hand, the measured self inductances were much smaller than the other measurements obtained at no TF current. The self induced voltage was almost cancelled out by using a single Wheatstone bridge of the quench detectors; whereas, the mutually induced voltage was cancelled out by numerically subtracting outputs of two Wheatstone bridges for coils, which were symmetrically located in the assembled coils.</P>

(Review Article) Status of the KSTAR Project

KIM, Keeman,OH, Yeong-Kook,S. BAK, Joo,KWON, Myeun,LEE, Gyung-Su,KSTAR team, The 低溫工學協會 2006 低溫工學 Vol.41 No.5

<P>The KSTAR project was started in 1996 and conducted in three phases, the conceptual design phase (1996-1998), the R&D and engineering design phase (1998-2002), and the construction phase (2002-2007). The mission of the Korea Superconducting Tokamak Advanced Research (KSTAR) Project is to develop a steady-state-capable advanced superconducting tokamak for establishing a scientific and technological basis for an attractive fusion reactor. Since the KSTAR mission includes the achievement of a steady-state-capable operation, the use of superconducting coils is an obvious choice for the magnet system and the long pulse current drive and heating systems are also the important aspect of the KSTAR design features. The advanced tokamak aspect of the mission is incorporated in the design features associated with flexible plasma shaping, double-null divertor and passive stabilizer, internal control coils. All the major components are in the stage of the fabrication and assembly for the completion of the KSTAR construction in the year 2007.</P>

Development of In-Vessel Vertical Coil Power Supply in KSTAR

Jong-Kook Jin,Jae-Hoon Choi,Dong-Keun Lee,Sang-Hee Han,Young-Mu Jeon,Yaung-Su Kim,Myeun Kwon,Hyun-Sik Ahn,Gye-Yong Jang,Min-Seong Yun,Dae-Kyung Seong,Hyun-Seok Shin IEEE 2013 IEEE transactions on plasma science Vol.41 No.7

<P>The Korea Superconducting Tokamak Advanced Research (KSTAR) device is an advanced superconducting tokamak to establish scientific and technological bases for an attractive fusion reactor [1]. In-vessel vertical coil (IVC) power supply (PS) is developed for vertical stability and shape control of KSTAR plasma. IVC PS in KSTAR is based on a single-phase full-bridge inverter. The output voltage and current are dc ±1 kV and ±10 kA, respectively. Insulated gate bipolar transistor is used as switching power device in IVC PS and maximal 5 kHz of switching frequency is adopted to meet the requirement of fast control by plasma control system. This paper describes the configuration and engineering of the IVC PS system and analyzes both the IVC coil commissioning and the major performances that D-shape plasma achieved in experiments.</P>

Stabilization of the KSTAR Power System for the First Plasma Operation

Jong-Dae Kong,Seong-Lok Hong,In-Sung Hwang,Jae-Hoon Choi,Chang-Hwan Kim,Dong-Keun Lee,Yaung-Soo Kim,Myeun Kwon,Byung-Ju Park,Hang-Kyu Yoo IEEE 2010 IEEE transactions on plasma science Vol.38 No.9

<P>After more than ten years of construction, the Korea Superconducting Tokamak Advanced Research (KSTAR) device finally completed its assembly in June 2007. We conducted the first plasma operation from April 2008 to July 2008 and succeeded in the plasma generation in July 2008. The electric power system for the first plasma operation is made up of various electric devices, including 154-kV circuit-breaker systems, a 154/22.9-kV 50-MVA transformer, 22.9-kV circuit-breaker systems, and reactive power compensator (RPC) and harmonic filter (HF) systems. When the poloidal-field magnet power supplies were operated, the reactive power and harmonic currents (12n ± 1) were generated instantaneously in the KSTAR electric power system for the first plasma generation due to the characteristics of the KSTAR superconducting coils. The measured voltage drop and harmonics seriously affected the other experimental equipment as well. Therefore, it is important to compensate the reactive power and remove the harmonics with the RPC and HF system for the superconducting tokamak device. In this paper, we discuss the stability of the electric power system and the operational results of the RPC and HF systems during the KSTAR first plasma operation. Furthermore, the upgrade plan of the electric power system based on the KSTAR operation plan will be discussed.</P>

Superconducting Magnet Power Supply System for the KSTAR 2nd Plasma Experiment and Operation

JAE HOON CHOI,DONG KEUN LEE,CHANG HWAN KIM,Jong-kook Jin,Sang-Hee Han,JONG DAE KONG,SEONG LOK HONG,Yang-Su Kim,MYEUN KWON,Hyun-sik Ahn,Gye-yong Jang,Min-seong Yun,Dae-Kyung Seong,Hyun-seok Shin 대한전기학회 2013 Journal of Electrical Engineering & Technology Vol.8 No.2

The Korea Superconducting Tokamak Advanced Research (KSTAR) device is an advanced superconducting tokamak to establish scientific and technological bases for attractive fusion reactor. This device requires 3.5 Tesla of toroidal field (TF) for plasma confinement, and requires a strong poloidal flux swing to generate an inductive voltage to produce and sustain the tokamak plasma. KSTAR was originally designed to have 16 serially connected TF magnets for which the nominal current rating is 35.2 kA. KSTAR also has 7pairs of poloidal field (PF) coils that are driven to 1 MA/sec for generation of the tokamak plasma according to the operation scenarios. The KSTAR Magnet Power Supply (MPS) was dedicated to the superconducting (SC) coil commissioning and 2nd plasma experiment as a part of the system commissioning. This paper will describe key features of KSTAR MPS for the 2nd plasma experiment, and will also report the engineering and commissioning results of the magnet power supplies.