• Title/Summary/Keyword: Arc type

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A Study on Welding Performance Improvement of $CO_2$ Inverter Arc Welding Machine by Arc Reignition Detection (아크 재생 검출에 의한 $CO_2$ 인버터 아크 용접기의 용접성능향상에 관한연구)

  • 이정락
    • Proceedings of the KIPE Conference
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    • 2000.07a
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    • pp.581-586
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    • 2000
  • Gas metal arc welding(GMAW) uses a continuously fed electrode as a filler metal. The arc is shielded from atmospheric contamination by an inert gas active or inert/active gas mixture delivered through the welding gun and cable assembly. The recent research topics on $CO_2$ are welding machines are focused mainly on the reduction method of generated spatter by using new type consumable electrode metal or inverter control method. The various current waveform control methods have been researched for welding performance improvement. Until now current waveform control methods reduce to spatter occurred by instantaneous short circuiting,. but these methods is drawback that no reduce spatter occurred by arc reignition. In this paper the previous arc reignition current control method for welding performance improvement of inverter arc welding machine is studied and compared the various current control methods with the previous arc reignition current control method.

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Investigation of Arc Breaking Characteristic for Arc Chamber in Molded Case Circuit Breakerg (배선용차단기의 소호구조에 의한 한류 특성 연구)

  • Kim, Yong-Gi;Song, Jung-Chun;Ryu, Man-Jong
    • Proceedings of the KIEE Conference
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    • 2001.07b
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    • pp.708-710
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    • 2001
  • In this paper, back commutation phenomena for iron chute chamber in AC low testing. For this experimental we used high speed camera and carried out with same prospective currents up to 10kA RMS. Hybrid arc quenching chambers which are composed with iron plate and insulating materials tested for reducing back commutation phenomena in interrupting process. It is shows that hybrid chambers which are various narrow slot path width reduces back commutation. As a result, a new type arc quenching chamber is to force the arc rapidly into a narrow insulating slot with iron plate. By this means the arc is lengthened and squeezed between insulating walls. Using this model, the behavior of the arc squeezed in the hybrid chamber and characteristics of arc voltage are also investigated.

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ABLATION OF PTFE NOZZLE DRIVEN BY ARC PLASMA (아크 플라즈마에 의한 PTFE 노즐 용삭현상)

  • Lee J.C.;Kim Y.J.
    • 한국전산유체공학회:학술대회논문집
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    • 2005.10a
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    • pp.311-317
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    • 2005
  • It has been the most progressive interruption technique to use the ablation gas from the surface of PTFE nozzle driven by arc plasma during switching process in $SF_6$ gas circuit breakers. This advanced interruption technique can reduce the required mechanical energy to compress and blow the gas for extinguishing the arc plasma between the electrodes due to using the ablation effect instead. In order to consider the phenomena during calculation of switching process, it is required to confirm the principles of ablation from PTFE nozzle as well as of arc plasma during switching process. In this study, we have calculated the switching process considered the ablation of PTFE nozzle driven by arc plasma using multidisciplinary simulation technique and compared the results with the data without the ablation effect. More $50\%$ difference of pressure rise inside expansion chamber has been found from the results and it should be indispensable for this type of computational work to consider and include the ablation effect of PTFE nozzle. Further study on turbulence and radiation will be followed.

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Experiment on DC Circuit Breaker for Inductive Load by Improved Magnetic Arc-extinguisher and Arc-Attenuation Circuit (개선된 자기소호회로와 아크전압 억제회로를 사용한 유도성 부하의 직류차단 특성 실험)

  • Lee, Sung-Min;Kim, Hyo-Sung
    • The Transactions of the Korean Institute of Power Electronics
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    • v.17 no.6
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    • pp.495-499
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    • 2012
  • Recently, DC distribution systems become hot issues since DC type loads increase rapidly according to the expansion of IT equipment such as computers, servers, and digital devices; DC type loads will cover 50% for all electricity loads in 2020 which was mere 10% in 2000. DC distribution systems are also accelerated by the expansion of renewable power systems since they are easy to be interfaced with DC grids rather than AC grids. However, removing the fault current in DC grids is comparably difficult since the current in DC grids has non zero-crossing point like in AC grids. Thus, developing dedicated DC circuit breakers for DC grids is necessary to get safety for human and electrical facilities. Magnet arc extinguishing method is proper to small size DC circuit breakers. However, simple Magnet arc extinguishing method is not enough to break inductive fault currents. This paper proposed a novel DC circuit breaker against inductive fault current defined by IEEE C37.14-2004 Standard for Low-Voltage DC Power Circuit Breakers Used in Enclosures. The performance of the proposed DC circuit breaker was verified by an experimental circuit breaker test system built in this research.

Option of Network Flow Problem Considering Uncertain Arc Capacity Constraints (불확실한 arc용량제약식들을 고려한 네트워크문제의 최적화)

  • 박주녕;송서일
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.13 no.21
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    • pp.51-60
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    • 1990
  • In this paper we deal with the miniaml cost network flow problem with uncertain arc capacity constraints. When the arc capacities are fuzzy with linear L-R type membership function, using parametric programming procedure, we reduced it to the deterministic minimal cost network flow problem which can be solved by various typical network flow algorithms. A modified Algorithm using the Out-of-kilter algorithm is developed.

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COMPUTER SIMULATION OF ARC INTERRUPTION USING FEM FOR $SF_6$ GAS CIRCUIT BREAKERS

  • Park, K.Y.;Chong, J.K.;Song, K.D.;Lee, B.Y.;Mu, J.W.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.05a
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    • pp.68-73
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    • 2000
  • An arc model based on the N-S equations modified by adding an energy source term to take account of the arc is developed and solved using Taylor-Galerkin FEM. The numerical method is applied to the simulation of the interruption process of a puffer type GCB. Moving boundary conditions of the arc chamber during operation is taken into account. The thermal interruption capability of an actual puffer type GCB will be predicted and compared with that of the measured result.

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A Study on the Arc Characteristics of Axial Magnetic Field Type Electrode for Vacuum interrupter by Desing Parameters (설계변수에 따른 진공인터럽터용 종자계방식 전극의 아크특성에 관한 연구)

  • Kim, S.I.;Park, H.T.;Ahn, H.I.;Seo, J.M.
    • Proceedings of the KIEE Conference
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    • 2001.07b
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    • pp.672-674
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    • 2001
  • Axial magnetic field(AMF) type electrode can increase the interrupting capability of vacuum interrupters. But, this interrupting capability vary with design parameters such as shape of electrode, slits of contact, material of contact and so on. In this paper, shown arc characteristics of unipolar axial magnetic field type electrode for vacuum interrupter by design parameters such as shape of contact slits and diameter of contact. And, confirmed vacuum arc configuration by individual design parameter using high speed camera.

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Characteristics of Interruption Ability in DC Circuit Breaker using Superconducting Coil (초전도 코일을 이용한 DC 회로 차단기의 차단 능력 특성)

  • Jeong, In-Sung;Choi, Hye-Won;Youn, Jeong-Il;Choi, Hyo-Sang
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.68 no.1
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    • pp.215-219
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    • 2019
  • Development of DC interruption technology is being studied actively for enhanced DC grid reliability and stability. In this study, coil type superconductor DC circuit breaker was proposed as DC interruption. It is integration technology that combined current-limiting technique using superconductor and cut-off technique using mechanical DC circuit breaker. Superconductor was applied to the coil type. In simulation, Mayr arc model was applied to realize the arc characteristic in the mechanical DC circuit breaker. PSCAD/EMTDC had used to model and perform the simulation. To find out the protection range of coil type superconductor DCCB, the working operation have analyzed based on the rated voltage of DCCB. The results confirmed that, according to apply the limiting device, the protection range was increased in twice. Therefore, the probability of failure of interruption has lowered significantly.

Design of Drag-type Vertical Axis Miniature Wind Turbine Using Arc Shaped Blade (아크형 날개를 이용한 항력식 수직축 소형 풍력 터빈 설계)

  • Kim, Dong-Keon;Kim, Moon-Kyung;Cha, Duk-Keun;Yoon, Soon-Hyun
    • The KSFM Journal of Fluid Machinery
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    • v.9 no.2 s.35
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    • pp.7-12
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    • 2006
  • This study is to develop a system of electric power generation utilizing the wind resources available in the domestic wind environment. We tested drag-type vortical wind turbine models, which have two different types of blades: a flat plate and circular arc shape. Through a performance test, conditions of maximum rotational speed were found by measuring the rpm of wind turbine. The rotational speed was measured by a tachometer in a wind tunnel and the tunnel wind speed was by using a pilot-static tube and a micro manometer. The performance test for a prototype was accomplished by calculating power, power coefficient, torque coefficient from the measurement of torque and rpm by a dynamometer controller From the measurements for miniature turbine models with two different blades, the circular arc shape was found to Produce a maximum rotational speed for the same wind velocity condition. Based on this result, the prototype with the circular arc blade was made and tested. We found that it produces 500W at the wind velocity of 10.8 m/s and the power coefficient was 20%.

Relation between Arc Phenomena and Spattering Ratio of Flux Cored Arc Welding with 100% $CO_2$ Shielding gas (플럭스 코어드 아크 용접의 아크현상과 스패터 발생량과의 관계)

  • S.W. Kang;D.S. Um;E.S. Oh;D.S. You
    • Journal of the Society of Naval Architects of Korea
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    • v.35 no.4
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    • pp.65-75
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    • 1998
  • The $CO_2$ welding with 100% $CO_2$ gas is commonly used because of its cost and efficiency. Arc phenomena and spattering ratio of the $CO_2$ welding are influenced by various factors such as chemical compositions of welding wire, shielding gas, welding condition and welding power source etc.. Spattering ratio is predominantly influenced by the welding condition which determines a droplet transfer rode. In this study, arc phenomena and spattering ratio are investigated by using two type of FCW(titania type, semi-metal type). Then, the welding quality and optimum welding condition can be selected. From this study, the following results ware obtained; 1) In low current range(140A), FCW up to welding voltage(22V) resulted in a typical short circuit transfer, increase of spattering ratio and growth of spatter diameter. 2) In high current range(320A), the arc stability in titania FCW of a typical globular transfer is better than that of semi-metal FCW.

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