• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2022년도 추계학술대회
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• pp.536-538
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• 2022

Space-time line code (STLC)라는 새로운 다이버시티 기술의 발명 이후로, 오류율과 에르고딕 용량이 이론적으로 분석되었지만, 아웃티지 확률에 대한 연구가 수행되지 않았다. 본 논문에서는 STLC 시스템의 순시 신호 대 잡음비의 확률 밀도 함수를 도출하고, 아웃티지 확률의 닫힌-형식 표현을 수학적으로 유도하였다. 또한, 전산 실험을 통하여 분석 결과의 정확성을 검증하고, 시스템 설계 및 구현에 대한 통찰을 제시하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.74-78
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• 2002

In this study, We propose equations which can determine the number of sectionalizing switches for minimizing the outage and switch installation cost.

• 대한전기학회논문지:전력기술부문A
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• 제51권4호
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• pp.183-187
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• 2002

The efficient and rational transmission tariff structure is one of the crucial factors in creation of fair and competitive electricity markets. Transmission charge can be largely categorized into the line usage charge, system reliability charge, access charge and others. Any transmission tariff should be able to reflect these cost components reasonably. This paper suggests an approach amenable to allocating the transmission reliability costs reasonably with reflection of line sensitivity and line outage rate.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 추계학술대회 논문집 전력기술부문
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• pp.60-62
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• 2004

Transmission line outage is influenced by several weather factors: wind, rain snow, temperature, cloud and humidity. And most power system reliability studies assume a failure rate. It can be calculated by transmission line outage data and weather data. Also weather is divided into normal weather and adverse weather by failure rate analysis. The effect of failure rate is discussed with both normal weather and adverse weather. It can be used in effective information about system operation and planing.

• 대한전기학회논문지:전력기술부문A
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• 제53권10호
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• pp.550-555
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• 2004

Fault section isolation and service restoration are very important for function of DAS. In Japan, a progressive protection method is used for the line to ground fault section isolation and service restoration. But the progressive protection method has a drawback that the customer will experience outage time and that the rate in use of the feeder is not over 50%. This paper presents a new Service Restoration Algorithm which is for the line to ground fault section isolation and service restoration method for a ungrounded distribution system. If the proposed algorithm is used, the rate in use of the feeder can improve than before because a distribution system can change multi connection of feeder and the customer's outage time can be reduced. The proposed algorithm has been successfully tested in a distribution system.

• 조명전기설비학회논문지
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• 제22권10호
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• pp.118-125
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• 2008

송전선로에 발생하는 정전은 산업계에 큰 영향을 미치고 있다. 특히 낙뢰에 의한 송전선로의 사고는50[%]를 넘고 있다. 송전선로에 발생하는 낙뢰에 의한 정전을 줄이기 위해서는 경제적인 관점을 고려하여 보강대책을 수립하는 것이 중요하다. 송전선로의 신뢰도는 보통 연간 100[km]당 몇 건의 낙뢰에 의한 사고가 발생하는가에 의해 결정되므로, 낙뢰에 대한 보호 대책을 수립하기 위해서는 뇌 사고율을 정확하게 예측하는 것이 필요하다. 낙뢰에 의한 절연물의 섬락현상은 대단히 복잡한 전기자기적 현상이다. 또한 송전선로의 뇌 사고율을 계산하기 위해서는 수많은 반복계산이 요구된다. 따라서 프로그램의 개발이 요구되며, 본 논문에서는 송전선로 뇌 사고율 계산을 위한 기본개념 및 개발된 프로그램을 검증하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.79-82
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• 2002

The addition of switches to a distribution feeder does, in general, increase reliability by decreasing the duration of the outage of many to the customers on the feeder. To cover its service area so that feeder-level delivery reaches sufficiently close to all customers, feeders typically split their routes many times, in what is often called a lateral feeder. It is interesting to note, however, that the effectiveness of a switch is very much dependent on the types of lateral feeder. The types of lateral are classified into two types. The first is loop lateral feeder that can connect its load to an adjacent feeder through a tie line in case that a fault occurs in its feeder and it is laid out so that every feeder has complete fault backup through re-switching of its loads to other sources like a main feeder. The second is the radial lateral feeder cannot connect its load to an adjacent line, no provision is made for contingency backup of feeders. There are no other circuits in the radial lateral feeder form which to restore power. In this study, we evaluate the effectiveness of a switch installation between on the radial and loop lateral feeders to increase reliability by decreasing the duration of the outage. These results can help power utility to design the switch layouts on the radial and loop lateral feeder system.

• 대한전기학회논문지:전력기술부문A
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• 제51권6호
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• pp.290-295
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• 2002

The present assignment in installing the number of switches for distribution line was made on the basis of a normal feeder capacity 7,000kVA in KEPCO(Korea Electric Power Corporation), Korea. But the normal capacity is revised to 10000kVA in 1998. Even increasing limit of the operating capacity of the distribution lines enables us to give some benefit for the operation flexibility and investment cost of the distribution system. It is disadvantageous in the viewpoint of supply reliability. In distribution systems, switches are equipped to improve the reliability of distribution systems by minimizing the outage section due to fault and maintenance. Utility generally improves the reliability by minimizing the length of outage section, which is caused by fault and maintenance, through switch equipment on distribution system. In order to cope with the changes such as operation capacity, it is necessary to study whether the present criteria is reasonable or not, also to confirm whether the present criteria of installing switches in line is improved or not. In this study, we proposes the number of switch per feeder on the basis of present operation capacity in distribution system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 A
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• pp.515-517
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• 2001

The efficient and rational transmission rate system is one of the crucial factors in creation of fair and competitive electricity market. Transmission charge can be largely categorized into the line usage charge, system reliability maintenance charge, access charge and others. Therefore, transmission rate structure should be able to reflect these cost components reasonably. This Paper suggests an approach that could be used for the reasonable calcuation of transmission reliability costs with reflection of line sensitivity and line outage rate.

• KEPCO Journal on Electric Power and Energy
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• 제8권1호
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• pp.15-19
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• 2022

The radial distribution systems (RDS) commonly used around the world has the following disadvantages. First, when the DL is operated on a radial system, the line utilization rate is usually kept low. Second, if a fault occurs in the radial DL, a power outage of 3 to 5 minutes is occurring depending on the operator's proficiency and fault situation until the fault section is separated and the normal section is replaced. To solve this problem, Various methods have been proposed at domestic and foreign to solve this problem, and in Korea, research is underway on the advanced system of operating multiple linked DL always. A system that is electrically linked always, and that is built to enable high-speed communication during the protection coordination is named networked distribution system (NDS). Because the load shares the DL, the line utilization rate can be improved, and even if the line faults, the normal section does not need to be cut off, so the normal section does not experience a power outage. However, since it is impossible to predict in which direction the fault current will flow when a failure occurs in the NDS, a communication-based protection coordination is used, but there is no backup protection coordination method in case of communication failure. Therefore, in this paper, we propose a protective cooperation method to apply as a backup method when communication fails in NDS. The new method is to change TCC by location of CB using voltage drop in case of fault.