• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.9
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• pp.1646-1650
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• 2011

SAIDI(System Average Interruption Duration Index) is the index that signifies the power quality of customers. SAIDI is also used to know how well utilities operate their systems. The annual interruption time in the areas that consists of widely distributed customers, is generally longer than that in the areas that consists of heavily concentrated customers. The Reliability index of huge system is not necessarily better or worse than that of small system, because SAIDI is irrelevant to the total amount of power sold or the total number of customers. This paper proposes a customer density very relevant to SAIDI. The proposed customer density is used to modify the existing SAIDI to more clearly express the service level of power supply. A modified WSAIDI(weighted SAIDI) can be a useful indicator helping utilities improve the reliability of their systems and customers evaluate the service level of receiving power.

• Proceedings of the IEEK Conference
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• 2002.07a
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• pp.433-436
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• 2002

Most of electric distribution utilities have their reliability performance measured by reliability indices such as SAIFI and SAIDI to evaluate customer satisfaction. Adding protective devices in electrical distribution system can increase the system reliability by protecting public customers from local faults. In large-scale distribution system, it is difficult to determine the positions of these protective devices, which can efficiently protect customers within utilities' investment. In this paper, we propose an optimization technique to identify types and positions of protective devices to minimize SAIFI and SAIDI indices according to system requirement constraints.

• 한국전산유체공학회:학술대회논문집
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• 2008.08a
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• pp.66.1-66.1
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• 2008

• 한국전산유체공학회:학술대회논문집
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• 2008.08a
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• pp.66.2-66.2
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• 2008

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.977-977
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• 2006

• Proceedings of the Korea Water Resources Association Conference
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• 2005.09a
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• pp.625-627
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• 2005

• Communications of the Korean Mathematical Society
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• v.25 no.3
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• pp.391-404
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• 2010

The well-known characterizations of the Schwartz space of rapidly decreasing functions is extended to new algebras of rapidly decreasing generalized functions.

• KIEE International Transactions on Power Engineering
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• v.5A no.3
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• pp.260-268
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• 2005

This paper proposes an improved investment pnonty decision method of facilities considering the reliability of distribution networks. The proposed method decides an investment order of the facilities combining, by fuzzy rules, the investment priority decision by KEPCO and that by reliability evaluation indices. The reliability evaluation indices are SAIFI (System Average Interruption Frequency Index) and SAIDI (System Average Interruption Duration Index). The reliability analysis method of distribution networks applied in this paper utilizes the analytic method, where the used reliability data is the historical data of KEPCO. Particularly, we assumed that the failure rate increases as the equipment ages. To verify the performance of the proposed method, we applied it with the planned projects to reinforce the weak electrical facilities in KEPCO in 2004. The evaluation result showed that, under a limited budget, the reliability of KEPCO in the Busan region using the proposed method could be enhanced if used rather than the conventional method typically in place. Therefore, the results verify that the proposed method can be efficiently used in the actual priorities method for investing in the electrical facilities.

• Proceedings of the KIEE Conference
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• 2006.07a
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• pp.478-479
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• 2006

배전계통의 전기품질을 평가하기 위한 중요한 요소는 여러 가지가 있으며 그 대표적인 요소로 신뢰도 지수를 들 수 있다. 신뢰도 지수란 정전이 수용가에 미치는 영향을 정전시간과 정전수용가수로 표현한 지표로 공급에 대한 비신뢰도율을 나타낸다. IEEE 위원회는 다양한 지역을 벤치마킹하여 신뢰도 지수를 정의하였다. SAIFI와 SAIDI 등과 같이 공통적으로 사용 중인 지수가 있으며 지역의 특성에 따라 다양한 지수가 사용되고 있다. 이 논문에서는 IEEE에 정의된 전기품질 신뢰도 지수의 현황을 분석하고 국내에서 사용 중인 신뢰도 지수와 상호 비교하였다.

• Bulletin of the Korean Mathematical Society
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• v.56 no.1
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• pp.13-22
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• 2019

We compute the second cohomology of the affine Lie algebra aff(1) on the dimensional real space with coefficients in the space ${\mathcal{D}}^n_{{\underline{\lambda}},{\mu}}$ of n-ary linear differential operators acting on weighted densities where ${\underline{\lambda}}=({\lambda}_1,{\ldots},{\lambda}_n)$. We explicitly give 2-cocycles spanning these cohomology.