• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 추계학술대회 논문집
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• pp.227-227
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• 2009

To prevent such accidents, molded case circuit breakers with improved short-circuit current interrupting capacity are needed. This paper is focused on understanding the interrupting capability with respect to double contact structure and puffer assisted self quenching that are based on the shape of the contact system in the current molded case circuit breaker. The new arc quenching structure for increasing the interrupting capacity of molded case circuit breakers is investigated by simulation and experiment.

• 대한전기학회논문지
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• 제40권1호
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• pp.18-23
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• 1991

Recently SLAMECKA suggested the mathematical dynamic arc model of the SF6 gas circuit breaker [1]. The author applied the above dynamic arc model to the E.H.V. transmission line and investigated the interrupting capability of the SF6 gas circuit breaker. In particular the Runge-Kutta-England numerical method suitable for the use in systems that involve nonlinear dynamic arc and traveling wave was used by converting the current source into the voltage source in the DOMMEL's method [2]. The successful computer resultls were obtained and it was found that the arc time constant and the second derivative of the arc conductance are closely related to the interrupting capability of the SF6 gas circuit breaker.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.101-101
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• 2010

Power distribution system requires the transformer with higher capacity than ever, but this ever, but this may be the cause of the increasing of short circuit current in contrast to conventional one when short-circuit accident is occurred. Therefore molded case circuit breaker improved in aspects of interrupting capacity of short circuit current in this system is needed. The arrangement and quality of the material of grids in arc quenching room are also designed optimally by the analysis of arc driving forces.

• 전기학회논문지P
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• 제63권1호
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• pp.12-18
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• 2014

This paper analyzes how to calculate the three phase short circuit current calculation procedures used in the IEC 60909 short circuit. It presented the new procedure of the fault current for the interrupting capacity of the circuit breaker. This procedure is applied to the future power system and calculates the fault current. Power demands are increased because of the growth of the economy for this reason, the fault current of the power system is largely increased and the fault current procedure for the proper interrupting capacity calculation of the existing or the new circuit breaker is essential. How to calculate the three phase short circuit current for ac electrical system and select the high voltage and low voltage circuit breaker based on IEC 60909 standards.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.105-105
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• 2010

Voltage circuit breakers are widely used in power distribution systems to interrupt fault current rapidly and to assure the reliability of the power supply. Power distribution system requires the transformer with higher capacity than ever, but this ever, but this may be the cause. of the increasing of short circuit current in contrast to conventional one when short-circuit accident is occurred. Therefore molded case circuit breaker improved in aspects of interrupting capacity of short circuit current in this system is needed. By using the proposed methods in this paper, such as new arc quenching structure of grid would contribute to minimizing the MCCB, realization of high interrupting performance and reducing the design time and development cost.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 A
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• pp.30-32
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• 1995

The model interrupters of $SF_6$ gas electromagnetic contactor whose ratings are the voltage of 7.2kV and the short circuit current of 4.0kA have been designed and manufactured on the basis of theoretical and computational analysis for its development. The eddy current analysis, the magnetic field analysis and the calculation of the rotational force on arcs have been conducted using FLUX2D package. The short circuit current interrupting tests have been conducted to the model interrupters using the simplified capacitive synthetic test circuit in KERI. The results show that the model interrupters have a sufficient interrupting capability and the new design concept is proper for a good interrupting performance.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 C
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• pp.1863-1865
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• 2004

As rise the demands for the protcetion of environment and the compactness of equipments, the movement brisks for replacing the circuit breaker of GIS(Gas Insulated Switchgear) to VI(Vacuum Interrupter). For these reason an increase in the interruption capability of VI is required. To satisfy these requirement, the academic and industrial worlds have been studying extensively for AMF(Axial Magnetic Field) contact, which is effective in interrupting large current over tens of kA, and introduced many kind of AMF contacts. However there are little effort to compare these contacts comprehensively, so it is difficult to choose most suitable shape for user's needs. In this paper, focusing unipolar type contact among various type of AMF contacts, we performed magnetic field analysis for several models designed in same dimension and compared the result and characteristics of each model in order to help deciding the direction for developing profitable VIs for interrupting large current.

• 조명전기설비학회논문지
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• 제18권1호
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• pp.78-84
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• 2004

배선용 차단기(MCCB)는 신속한 고장전류 차단과 전원시스템의 안정성을 확보하기 위해 배선시스템에 폭넓게 사용되고 있다. 본 논문에서는 MCCB의 소호부 형상에 따른 차단성능을 파악하고 이를 통해 성능향상을 꾀하고자 3차원 자계해석을 이용한 차단성능 평가해석기법을 개발하고, 개발한 평가해석기법을 각 모델 차단기에 적용한 바를 기술하였다. 또한, 소호부내 아크런너의 형상을 불연속 통전경로로 구성하여 차단성능에 미치는 영향을 살펴보았다. 이상의 연구내용을 토대로 새로운 소호부 형상을 고안하여 국내 최초로 460 [V]/225 [A]/50 [kA] 대전력 단락시험에 성공한 결과를 제시하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 B
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• pp.628-632
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• 2002

Low voltage circuit breakers which interrupt rapidly and raise the reliability of power supply are widly used in power distribution systems. In the paper, it was investigated how much Interrupting capability was improved by correcting the shape of the contact system in molded case circuit breaker(below MCCB), especially arc runner. Prior to the interrupting testing, it was necessary for the optimum design to analyze electromagnetic forces on the contact system, generated by current and flux density. This paper presents both our compuational analysis and test results on contact system in MCCB

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 춘계학술대회 논문집
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• pp.28-28
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• 2010

The higher the short circuit currents, the faster the interruption takes place. For increasing the interrupting performance of the MCCB, it is important to design optimally the adjustable tripping device, the open /shut mechanism, and the arc quenching room in the MCCB. This paper is focused on understanding the interrupting performance, more specifically of the grid and the fix contact, based on the shape of the arc quenching room in the current MCCB.