• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.2570-2575
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• 2003

Monitoring a power transmission line is significant for power electric companies. In this paper, we propose a new method for detecting an fault point of power transmission line by use of M-sequence correlation technique. In this method, detecting signal is used as one or plural M-sequences ( same characteristic polynomial, including normal and reverse mark, synchronized ). In receiving point, we make same sequence with the input one and take crosscorrelation function between M-sequence and the received signal. We can see transfer fanctions of plural paths between inputs and a output taps separated from different of delay times on the crosscorrelation function, and from these transfer fanctions, so we compare them when fault occurred with in usual.

• 대한전기학회논문지:전력기술부문A
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• 제52권5호
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• pp.271-278
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• 2003

Power system stability is correlated with system structure, disturbances and operating conditions, and power flows on transmission lines are closely related with those conditions. This paper proposes a methodology to identify correlative power flows for power system transient and small-signal stability prediction. In transient stability sense, the Critical Clearing Time is used to select some dominant contingencies, and Transient Stability Prediction index is proposed for the quantitative comparison. For small-signal stability, this paper discusses a methodology to identify crucial transmission lines for stability Prediction by introducing a sensitivity factor based on eigenvalue sensitivity technique. On-line monitoring of the selected lines enables to predict system stability in real-time. Also, a Procedure to make a priority list of monitored transmission lines is proposed. The procedure is applied to a test system and the KEPCO systems in the year of 2003 and it shows capabilities of the proposed method

• 전기학회논문지
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• 제58권6호
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• pp.1071-1077
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• 2009

Because several winds cause the a fault of transmission supply, KEPCO trys to protect the the trouble and supply the power stably. Kepco find out the weak mountains by winds and strengthen the power equipment annually. Power quality is the competition power in the international world and satisfy the customer using th power Therefore this paper deals with the fault relation between winds and transmission line.

• 전기학회논문지
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• 제58권6호
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• pp.1238-1240
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• 2009

In the wireless sensor network, cooperative transmission is an effective technique to combat multi-path fading and reduce transmitted power. Relay selection and power allocation are important technical issues to determine the performance of cooperative transmission. In this paper, we proposed a new multi-relay selection and power allocation algorithm to increase network lifetime. The proposed relay selection scheme minimizes the transmitted power and increase the network lifetime by considering residual power as well as channel conditions. Simulation results show that proposed algorithm obtains much longer network lifetime than the conventional algorithm.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.40-41
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• 2006

KEPCO conducted the project called the "Feasibility Study & Basic Designs for the 500kV Transmission System in Myanmar" as its second overseas project following the "Development Study on the Power System Network Analysis in Myanmar" as it first project. This paper deals with the design processes and results of 423 kilometers of the 500kV single circuit transmission lines and three substations. The main contents of the basic design include insulation design, transmission line design and substation design.

• 한국초전도ㆍ저온공학회논문지
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• 제4권1호
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• pp.61-65
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• 2002

It becomes difficult and high in cost to construct new ducts and/or tunnels for power cables in metropolitan areas. This paper presents possible applications of an HTS superconducting power cables for transmitting electric power in metropolitan areas. Reflected were its important distinction such as compactness for installation in underground ducts and considerably high efficiency compared with present underground cables. In this paper, system modeling, transmission capacity and voltage class of compact HTS cables which should be applied to existing ducts were reviewed. Based on this, the following items on urban transmission system are examined. (1) A method of constructing a model system to introduce high temperature superconducting cables to metropolitan areas is presented. (2)The maximum outer diameter of HTS cables to be accommodated in exiting ducts is calculated based on the design standards for current cable ducts. (3)The voltage level that can be accommodated by existing ducts is examined.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 A
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• pp.452-454
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• 2001

This paper described the calculation results of lightning flashover rate on the 345kV and 154kV transmission system of KEPCO. The back-flashover rate and shielding failure rate was calculated by FLASH(lightning flashover rate calculation program from IEEE) and KEPRI's own program which is based on the EGM(Electro Geometrical Model) method. The estimated lightning flashover late of 345kV transmission system of double circuit was 1.0 flash per 100km-year, and the lightning flashover rate of 154kV transmission line was 2.0 flash Per 100km-year approximately.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 E
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• pp.1678-1680
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• 1998

The purpose of this study is to obtain optimum arrangement of phase conductors in minimizing magnetic field from overhead transmission lines. Data of the transmission lines rated 345 kV of the KEPCO(Korea Electric Power Company)'s system were used. For a three phase-double circuit transmission line, low-reactance arrangement is optimum in minimizing magnetic fields. For a three phase-four circuit, optimum phase arrangement is a-b-c-b-a-c(lower two circuits, clockwise)/b-c-a-c-a-b(upper two circuits, clockwise).

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 E
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• pp.1908-1910
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• 1997

The electric and magnetic fields (EMFs) near 345/154 kV overhead transmission lines were measured. The average values of maximum electric field and magnetic field for 44 transmission lines were 1.11 kV/m and 24.5 mG, respectively. These values were lower than any standards of advanced countries. The EMFs of distribution lines and substation, and electric appliances were also measured and compared with those of transmission lines.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2009년도 추계학술대회
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• pp.1046-1048
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• 2009

협업통신은 다중경로페이딩의 문제를 해결하고 전송전력소모를 감소시키기위한 효과적인 기술이다. 릴레이선택과 전력할당은 협업통신의 성능을 결정하는 중요한 요소이다. 본 논문에서는 센서네트워크에서 네트워크수명 극대화를 위해 새로운 형태의 다중 릴레이선택 방법과 전력할당 알고리즘을 제안한다. 제안하는 릴레이 선택 알고리즘은 채널상태 뿐아니라 각 노드의 잔여전력을 함께 고려함으로써 전송전력을 극소화하고 네트워크의 수명을 증가시킨다. 시뮬레이션결과는 제안된 알고리즘이 기존의 방식에비해 더 긴 네트워크 수명을 갖을 수 있음을 보여준다.