• The Transactions of the Korean Institute of Electrical Engineers P
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• v.63 no.1
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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.

• Proceedings of the KIEE Conference
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• summer
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• pp.400-402
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• 2004

In this paper We are trying to get the process of fault analysis and it's algorithm which is IEEE and IEC standards as a criteria to choose the circuit breaker. And We'd like to compare IEEE standards' and IEC standards' fault analysis result for both fault current and it's magnitude by applying the same sample condition.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.255-256
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• 2008

개발된 프로그램은 C++ 언어를 사용하여 객체지향 프로그래밍 (Object Oriented Programming) 개념에 맞추어 설계되었다. C++과 같은 OOP 언어는 클래스 정의, 연산자 오버로딩, 상속, 캡슐화와 같은 차별적인 특성을 가지고 있어 대규모 프로그램의 작성과 관리에 매우 효과적이다. 전력 계통의 각 구성 요소들은 클래스로 설계되었으며 계산 모듈 또한 별도의 클래스로 디자인하여 향후 프로그램 개선과 확장을 용이하게 구현하였다. 개발된 프로그램은 편리한 Graphic User Interface (GUI)를 제공하기 위해서 Windows Application Programming Interface (API)와 Microsoft Fundamental Classes (MFC) 등을 이용하였으며 Microsoft Visual Studio.net 을 이용하여 컴파일 되었다 [1].

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.12
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• pp.6-12
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• 2014

The safety and reliability of the power system short-circuit current, the short-circuit current depends on the failure to obtain the objective is to quickly eliminate the breaking capacity of the circuit-breaker selection of the cable, the insulation of electrical equipment and protective relay an important factor in determining the level correction and protective relay selection scheme to be meaningful. Standards used in the domestic circuit breaker is applied to the production of IEC standard, but the American National Standards (ANSI / IEEE) by NEMA specification of the fault current calculations and the application of the asymmetric coefficient Korea. Therefore, in this paper, the IEC 60909 standard IEC breaker fault current calculation method and the method for selection of system configurations reviewed and protection system for reviewing the configuration of various protective relays appropriate correction and the correction value is main protection, back-up protection the equipment so that the period of protection relay coordination to minimize accidents and accident protection to minimize interruptions proposed for cooperation.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.54 no.6
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• pp.315-322
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• 2005

In this article, 1 would like to explore the estimation method of time-varying voltage sags in large industrial systems considering the short circuit contributions of rotating machines. For the power distribution system of KEPCO(Korea Electric Power Corporation), the magnitude of initial symmetrical short circuit current is generally not changed. However, in industrial systems which contain a number of rotating machines, the magnitude of voltage sag is generally changed from the initial to the clearing time of a fault due to the decreasing contribution of rotating machines for a fault current. The time-varying characteristics of voltage sags can be calculated using a short circuit analysis that is considered the time-varying fault currents. For this, the prediction formulations of time-varying voltage sags are proposed using a foreign standard. The proposed method contains the consideration of generator and motor effects. For the test of proposed formulations, a simple system of industrial consumer is used for the comparison conventional and proposed estimation method of voltage sag characteristics.