• 대한전기학회논문지:전력기술부문A
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• 제53권9호
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• pp.487-493
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• 2004

The electric power industry throughout the world is undergoing considerable changes from the vertically integrated utility structure to the deregulated market. However, the deregulated electricity market is operated with respect to theory of economical efficiency, and therefore, the system operator requires data with fast contingency ranking for security of the bulk power system. This paper compares the weather dependant probabilistic risk index(PRI) with the system performance index for power flow in the IEEE-RTS. The system performance index for power flow presents the power system stability. This paper presents fast calculation method for determining contingency ranking using the weather dependant probabilistic risk index(PRI). The probabilistic risk index can be classified into the case of normal and adverse weather. This paper proposes calculation method using the probabilistic risk index in determining contingency ranking required for security under the deregulated electricity market.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2002년도 학술논문발표회
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• pp.57-60
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• 2002

Recently, the coal ash production has been increased by increase of consumption of electric power. So it is important to find a reclaimed place and treatment utility for treating coal ash. Accordingly, in this study we performed an experimental study to compare and analyze the Properties of concrete according to W/C and bottom ash replacement ratio. As a result of this study, it was found that the bleeding content was decreased according to decrease of W/C and increase of bottom ash replacement ratio, and the compressive strength of concrete using bottom ash was similar to plain concrete(replacement ratio 0%).

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1996년도 추계학술발표회논문집(1)
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• pp.409-414
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• 1996

A model to estimate economic consequence of severe accident provides some measure of the impact on the accident and enables to know the different effects of the accident described as same terms of cost and combined as necessary. Techniques to assess the consequences of accidents in terms of cost have many applications, for instance in examining countermeasure options, as part of either emergency planning or decision making after an accident. In this study, a model to estimate the accident economic consequence is developed appropriate to our country focused on PWR accident costs from a societal viewpoint. Societal costs are estimated by accounting for losses that directly affect the plant licensee, the public, the nuclear industry, or the electric utility industry after PWR accident.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1991년도 하계학술대회 논문집
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• pp.478-481
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• 1991

This paper discusses the principle and structure of instantaneous voltage drop compensator, which protects damage from instantaneous voltage drop in systems such as computer, variable speed drive, high voltage discharge-lamp, magnet switch. When instantaneous voltage drop occurs, control circuits detect it, then produce output voltage the same as normal condition voltage. Instantaneous voltage drop compensator has condenser bank as energy storage component, so system can be made small, light weight compared with UPS. In normal state, utility source transfers power, and in instantaneous voltage drop state, the energy of condenser bank transfers power through inverter, so high efficiency, compact, and especially low cost system can be manufactured.

• 태양에너지
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• 제9권3호
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• pp.81-91
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• 1989

This study represents the method to predict the flow duration curve and primary design specifications of small hydropower plant at hydropower site through analyzing the monthly rainfall data. Weibull distribution was selected to characterize the rainfall data and Thiessen method was used to calculate monthly average flowrate at site. Application of these results, primary design specifications such as design flowrate, annual average load factor and utility factor, annual average hydropower density and annual electric energy production were estimated and discussed for surveyed site located in Daigi-ri, Kangwon province. And performance characteristic model of small hydro-power plant was applied to estimate these specifications.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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• pp.699-704
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• 2002

Recently, the coal ash production has been increased by increase of consumption of electric power. So it is important to find a reclaimed place and treatment utility for treating coal ash. Accordingly, in this study we performed an experimental study to compare and analyze the properties of concrete according to W/C and bottom ash replacement ratio. As a result of this study, it was found that the bleeding content was decreased according to decrease of W/C and increase of bottom ash replacement ratio, and the compressive strength of concrete using bottom ash was similar to plain concrete(replacement ratio 0%).

• 조명전기설비학회논문지
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• 제21권9호
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• pp.81-86
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• 2007

Electric utility companies have the responsibility of providing good electricity for their customers. They have introduced the DAS(Distribution Automation System) to automate the power distribution networks. DAS engineers require state-of-the-art applications, such as a way to actively manage the distribution system and gain economic benefits from a flexible DAS architectural design. The existing DAS is not capable of handling these needs. It requires operator intervention whenever feeder overloading is detected while operator error could cause the feeder overload area to be extended. It also utilizes a closed architecture and it is therefore difficult to meet the system migration and future enhancement requirements. This paper represents a web based, platform-independent, flexible DAS architectural design and active database application. Recent advanced Internet technologies are fully utilized in this new DAS architecture allowing it to meet the system migration and future enhancement requirements. By using an active database, the DAS can minimize the feeder overloading area in the distribution system without operator intervention, thereby minimizing mistakes due to operator error.

• 조명전기설비학회논문지
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• 제16권2호
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• pp.38-44
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• 2002

전력변환기와 같은 비선형 부하의 사용증가는 전력시스템에 고조파를 발생시킨다. 고조파를 포함하는 전류와 전압은 전기설비에 고장과 오동작을 일으키게된다. 위상조정 변압기는 고조파 발생원이 병렬로 설치되어 있는 곳에 설치하면 고조파 문제를 효과적으로 해결할 수 있다. 본 논문에서는 EDSA고조파 분석 프로그램을 사용하여 고조파를 제거하기 위한 위상조정 변압기의 효과를 분석하고 검증하였다.

• 전기학회논문지
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• 제60권9호
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• pp.1639-1645
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• 2011

A technique to allocate responsibilities among the interested parties in electric power system with harmonic voltage distortion at the point of common coupling (PCC) has been presented. The recursive least-squares technique has been used to estimate the parameters of the Thevenin equivalent load model. The validity of the technique has been verified using a simulation which considered the voltage waveform distortion at the PCC between the utility and two industrial consumers. With the estimated data from the measured voltage and current waveform at the PCC, the individual contributions to the distortion of voltage waveform at an interested harmonic frequency have been calculated and could provide a flexible solution to identify the source of harmonic pollution in distribution systems.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 A
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• pp.252-254
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• 2000

For many years, electric utility has used sustained interruption rates as a reliability index. Today, however, many electricity consumers are adversely affected by more subtle voltage disturbances such as harmonic distortion. This paper deals with observations of events that occur in the Dimmer circuits and phase control which could affect harmonics problem to the commercial power system. In order to reduce the effect of harmonics and design filters, Solid State Relay Dimmer(SCRs or TRIACs) and Noise Filter are described, and the effects of harmonics is also analyzed. IGBT Dimmer which is appropriate method to reduce harmonics and improve efficiency is introduced.