• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 추계학술대회 논문집 전력기술부문
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• pp.122-124
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• 2003

In recent, the various electric & electronic machines are newly developed everyday and the electricity supply system & environment on the process from generation to consumption of electricity also is being changed. In other words, both supplier and consumer of electricity are required to be responsible for their interruption costs. So, it is very important and meaningful work for evaluating the interruption costs in quantitative. Additionally, since the restructuring of electric industry is on going in world wide, after restructuring, most of all electric utilities and consumer have to consider the supply reliability and quality as a important element of the calculating the related costs and contract because it takes costs to keep the supply reliability and quality highly. Especially, the interruption or the supply reliability will have influence on the bilateral contract between supplier and customer as a key point to determine the once in competitive electric market. Therefore, it has very important moaning to calculate the interruption costs in the present that it is prepared to open the competitive electric market. In this paper, international standards, i.e. IEC, IEEE, are applied to the analysis on the interruption costs used in the questionnaires which are newly designed including short duration interruption by the authors instead of traditional interruption criteria. Firstly, using the questionnaires, the authors got related data from industries according to the standard industry classification which are being used in electric utility and other national statistics in Korea. However, analysis results are hard to say typical value because of the not so many samples. So, the authors are going to survey and focus on not all kinds of industry but a few kinds of them that their facilities are effected or stop by short duration interruptions, so there are large economical damages. Finally, the authors hope to find the reliable and meaningful model in interruption costs of industrial customer.

• 펄프종이기술
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• 제46권1호
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• pp.18-28
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• 2014

Renewable Portfolio Standards(RPS) is a regulation that requires a renewable energy generated from eco-friendly energy sources such as biomass, wind, solar, and geothermal. The RPS mechanism generally is an obligatory policy that places on electricity supply companies to produce a designated fraction of their electricity from renewable energies. The domestic companies to supply electricity largely rely on wood pellets in order to implement the RPS in spite of undesirable situation of lack of wood resources in Korea. This means that the electricity supply companies in Korea must explore new biomass as an alternative to wood. Palm kernel shell (PKS) and empty fruit bunch (EFB) as oil palm wastes can be used as raw materials used for making pellets after their thermochemical treatment like torrefaction. Torrefaction is a pretreatment process which serves to improve the properties including heating value and energy densification of these oil palm wastes through a mild pyrolysis at temperature typically ranging between 200 and $300^{\circ}C$ in the absence of oxygen under atmospheric pressure. Torrefaction of oil palms wastes at above $200^{\circ}C$ contributed to the increase of fixed carbon with the decrease of volatile matters, leading to the improvement of their calorific values over 20.9 MJ/kg (=5,000 kcal/kg) up to 25.1 MJ/kg (=6,000 kcal/kg). In particular, EFB sensitively responded to torrefaction because of its physical properties like fiber bundles, compared to PKS and hardwood chips. In conclusion, torrefaction treatment of PKS and EFB can greatly contribute to the implement of RPS of the electricity supply companies in Korea through the increased co-firing biomass with coal.

• 자원ㆍ환경경제연구
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• 제24권4호
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• pp.629-655
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• 2015

국내 발전량의 30% 이상을 차지하는 원자력발전은 기저부하의 안정성 확보 측면에서 전력산업에서 중요한 위치를 차지하고 있다. 본 연구에서는 원자력 발전과 도매전력가격의 관계를 분석하고자한다. 이를 위해 자기회귀시차분포 (ARDL: Autoregressive Distributed Lag Model) 모형과 Granger 인과성을 통해 원자력발전과 전력도매가격 (SMP: System Marginal Price)의 관계를 살펴보았다. 분석결과 단기적 효과는 다르게 나타날 수 있지만 총 효과 (장기효과)로 볼 때 원자력공급량과 SMP는 양(+)의 관계로 나타났다. 일반적인 장기균형식에서 원자력발전용량은 SMP와 양 (+)의 관계인 반면에 시차변수를 포함한 ARDL 모형의 경우 발전용량은 SMP와 음 (-)의 관계로 이론에 부합하는 것으로 나타났다. 인과성 검정결과 원자력발전 공급량은 SMP에 일방향의 Granger 인과성이 있으나 그 역의 관계는 성립하지 않는 것으로 나타났다. 시계열분석을 통하여 원자력발전은 SMP와 밀접한 연관성을 갖고 있음을 발견할 수 있었다.

• 한국태양에너지학회 논문집
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• 제38권4호
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• pp.55-66
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• 2018

nZEH (net-Zero Energy House) is defined as a self-sufficient energy building where the sum of energy output generated from new & renewable energy system and annual energy consumption is zero. The electricity generated by new & renewable energy system with the form of distributed generation is preferentially supplied to electrical demand, and surplus electricity is transmitted back to grid. Due to the recent expansion of houses with photovoltaic system and the nZEH mandatory by 2025, the rapid increase of distributed generation is expected. Which means, we must prepare for an electricity-power accident and stable electricity supply. Also electricity charges have to be reduce and the grid-connected should be operated efficiently. The introduction of ESS is suggested as a solution, so the analysis of the load matching and grid interaction is required to optimize ESS design. This study analyzed the load matching and grid interaction by expected consumption behavior using actual data measured in one-minute intervals. The experiment was conducted in three nZEH with photovoltaic system, called all-electric houses. LCF (Load Cover Factor), SCF (Supply Cover Factor) and $f_{grid}$ (Grid Interaction Index) were evaluated as an analysis indicator. As a result, LCF, SCF and $f_{grid}$ of A house were 0.25, 0.23 and 0.27 respectively; That of B house were 0.23, 0.23, 0.19, and that of C were 0.20, 0.19, 0.27 respectively.

• 전기학회논문지
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• 제59권12호
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• pp.2143-2149
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• 2010

Market price and curtailment amounts of the Demand Resource Market(DRM) are determined by competition between electricity consumers. An important aspect of the DRM involves the assessment of strategic behavior of participants for maximizing their profits. This paper presents economic equilibrium models for simulating imperfect competition among electricity consumers in the DRM and analyzes the models at Nash Equilibrium of Game Theory. The proposed demand functions and supply functions of DRM are based on the Demand Resource Market Rules in Korean electricity market. Simulation results show that the models are adequate for obtaining Nash Equilibrium of consumers' competitive curtailment.

• 한국멀티미디어학회논문지
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• 제18권10호
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• pp.1231-1240
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• 2015

Nowadays, in islands where electricity should be provided autonomously, stand-alone microgrid technologies using renewable energy such as sunlight generation and wind power generation come into wide use. The microgrid electricity generation using renewable energy is greatly affected by the natural environment of a site. In order to maintain stable electricity supply for fluctuating electricity generation due to natural environment, the energy management via EMS is positively necessary. In existing stand-alone microgrid EMS, system operation logic is not changeable flexibly because compiled or builded codes are released into the EMS of a site, respectively. In this paper, we designed a flexible operating script-based microgrid EMS Framework for various sites and applied it to some island sites. We could confirm its usability.

• KIEE International Transactions on Power Engineering
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• 제5A권4호
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• pp.396-402
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• 2005

In an electricity market with imperfect competition, participants devise bidding plans and transaction strategies to maximize their own profits. The market price and the quantity are concerned with the operation reserve as well as the bidding system and demand curves in an electricity market. This paper presents a market model combined by an energy market and an operating reserve market. The competition of the generation producers in the combined market is formulated as a gaming of selecting bid parameters such as intersections and slopes in bid functions. The Nash Equilibrium (NE) is analyzed by using bi-level optimization; maximization of Social Welfare (SW) and maximization of the producers' profits.

• 응용통계연구
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• 제27권3호
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• pp.419-430
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• 2014

전력수급의 정확한 예측은 국민들의 일상적 생활 유지, 산업활동, 그리고 국가경영을 위하여 매우 중요하다. 본 연구에서는 시계열모형화에 의해 전력판매량을 예측한다. 실제 자료분석을 통하여 입력시계열로서 냉난방도일과 개입변수로 펄스함수를 사용한 전이함수모형이 다른 시계열모형에 비해서 제곱근평균제곱오차 및 평균절대오차의 의미에서 더 우수하였다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1999년도 전력전자학술대회 논문집
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• pp.226-229
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• 1999

The recent problems such as the rapid increase o electricity consumption, the large variation of electrical loads, and the sitting difficulty for new power plants could become a barrier to stable electrical power supply. Consequently, an electrical load management technology has become important, by which an electricity can be stored during off-peak time and efficiently used during peak time. The technology provides a variety of direct or indirect benefits which include, for utilities, reduction of new power plants, economical electricity production, and improved efficiency and reliability of power system and for consumers, low prices o electricity. The study is to develop a proto-type load management system and its application technology for a peak shaving. In the system, conventional batteries are used as energy storage device.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1990년도 하계학술대회 논문집
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• pp.87-91
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• 1990

Regional electricity demand forecasting is among the most important step for lone-term investment and power supply planning. This study presents a regional electricity forecasting model for Korean power system. The model consists of three submodels, regional economy, regional electricity energy demand, and regional peak load submodels. A case study is presented.