• Journal of Electrical Engineering and Technology
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• 제12권1호
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• pp.451-458
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• 2017

An Electric Vehicle (EV) is operated with the electric energy of a battery in place of conventional fossil fuels. Thus, a suitable charging infrastructure must be provided to expand the use of electric vehicles. Because the battery of an EV must be charged to operate the EV, expanding the number of EVs will have a significant influence on the power supply and demand. Therefore, to maintain the balance of power supply and demand, it is important to be able to predict the numbers of charging EVs and monitor the events that occur in the distribution system. In this paper, we predict the hourly charging rate of electric vehicles using transformation matrix, which can describe all behaviors such as resting, charging, and driving of the EVs. Simulation with transformation matrix in a specific region provides statistical results using the Monte-Carlo Method.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.151-156
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• 2008

The after 1974 capital region electric railroad is opened to traffic Koraill and Seoul metro adopt each other different power supply method and they operate and they are come. AC 25[kv] method voltage the insulation becomes larger standing distance highly, the case tunnel section which will introduce in the underground segment becomes on a large scale and the cost of construction increases to the city center and the underground segment adoption of DC method was many. To recent times with R-bar (Rigid-bar) introductions change of tunnel section the introduction of AC method came to be easy without in the underground segment. Operates sees in the electric protection where the Seoul metro and the Korail are different each other and, from the dead section segment the interior electric light to put out lights the passenger brings about inconveniently and the civil appeal which demands a power supply method unification occurs, within the company interchange electric railroad brazier safety improvement and maintenance expense curtailment etc. the flaw is original proposal, is a condition which finishes a feasibility study service about the power supply method fringe land. Interchange analysis of the DC electric railway it leads from the present paper and it compares under analyzing being it could be reflected to also the route which is in the process of actual using boil the strong point and a weak point of DC and AC method of the establishment route constructive at the time of and

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 A
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• pp.501-503
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• 2001

Electric power consumption is highly increasing as the social trend requiring comfortable life, the population in a big city and the industrial development. Therefore it has become to be very important to supply the stable high-quality power. As these trend, the underground power transmission facility is highly increasing in the center of a city. As the proportion to increase facility in tunnel, the fire prevention measures of the underground transmission line become very important.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2012년도 춘계학술대회
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• pp.378-379
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• 2012

현재 에너지 소비가 증가하면서 환경적인 이슈로 전력 산업의 고도화 및 에너지 효율화에 대한 요구가 증가함에 따라 지능형 전력시스템과 같은 전력 IT 산업이 신 성장 동력으로 주목받고 있다. 지능형 전력 시스템을 통해 전력 수요에 따른 공급의 밸런스를 최적화하게 되면 에너지 수입 및 전력 인프라 건설, 운영에 소요되는 막대한 비용을 절감할 수 있고, 안정적으로 전력을 공급할 수 있게 된다. 하지만, 모든 설비 및 장비를 실시간 관리하기 위해서는 인력낭비가 발생할 뿐만 아니라, 응급 상황을 인지하지 못해 전력사고로 이어지는 문제가 발생할 수 있다. 따라서, 본 논문에서는 스마트폰 기반의 원격 제어 및 모니터링 기능을 구비한 지능형 수배전반 통합관리 시스템을 개발하였다. 기존의 수배전반 관리 시스템의 단점을 보완한 본 시스템은 저비용으로 효율성과 안정성을 대폭 향상 시킬 수 있어, 향후 전력 IT 산업의 발전에 크게 도모할 수 있을 것으로 판단된다.

• 한국조명전기설비학회지:조명전기설비
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• 제6권1호
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• pp.29-39
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• 1992

In this paper, the basic idea of optimum electric system design by means of the forecasting of maximum demand is presented, and the load characteristics and practical operating conditions are based on the technical data. After reconstruction of th model plant by use of above method, power supply reliability, future extention, initial cost, and running cost saving effects are analyzed. As a result, it is verified that the systems wherein the power is supply to each load frm main transformer whose capacity is calculated by forecasting are economic rather than the systems wherein the power is supply to each electric feeders from each corresponding transformer.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.420-422
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• 2005

This paper introduces a new paradigm for energy supply system in near future which produces electric and district heat cogeneration with dispersed power grid with small nuclear power units. Recently, in nuclear field, a lot of effort has been done in nuclear major countries to develop small and medium reactor for enhancement of nuclear peaceful use as like in district heating, electric power generation, seawater desalination or hydrogen generation.

• 한국초전도ㆍ저온공학회논문지
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• 제14권3호
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• pp.43-47
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• 2012

A linear compressor generates pulsating pressure and oscillating flow in a cryocooler such as Stirling cryocooler and pulse tube refrigerator. It is driven by AC power source and designed to operate at resonance of piston motion. The driving voltage level is determined by electric parameters of resistance, inductance and thrust constant of linear motor. From voltage equation on linear motor, the power factor of driving power is inherently less than 1. The phase difference between voltage and current of supplied power can be zero using capacitor and this can minimize a supply voltage level. Especially, the linear compressor of kW class requires high voltage and thus can cause a difficulty in selecting power supply unit due to limitation of voltage level. The capacitor in driving electric circuit is useful to settle this problem. In this study, the electric circuit of linear compressor is analytically investigated with assumption of mechanical resonance. The electric parameters of commercial linear motor are used in the analysis. The effects of capacitor on driving voltage level and power factor are investigated. From analytic results, it is shown that the voltage level can be mimized with using capacitor in driving electric circuit.

• 에너지공학
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• 제18권2호
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• pp.114-124
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• 2009

지식경제부(MKE)는 매2년마다 전력수급기본계획을 수립한다. 본 논문에서는 전력수급기본계획 수립시 전력수요를 과대 또는 과소로 예측한 것이 차기 전력수급기본계획 수립시 전원혼합(Energy Mix)에 미치는 영향을 정량적으로 평가하였다. 전력수요 자료는 2005년도에 예측한 제3차 전력수급기본계획의 전망치를 이용하였고 전원혼합을 도출하기 위하여 전력거래소(KPX)에서 활용하고 있는 WASP 전산모형을 단순화한 시뮬레이션 모형을 구축하였다. 2005년도 전력수요를 적정, 5% 과대 그리고 5% 과소 예측한 경우에 대하여 각각 단순화한 시뮬레이션 모형을 이용하여 2005년도 전력수급기본계획의 전원혼합을 도출하였다. 이 3가지 전원혼합을 초기조건으로 하여 2005년도의 적정 전력수요가 2007년 이후에 적용된다고 보고 2007년도에 차기 전력수급기본계획의 전원혼합을 도출하였다. 전력수요가 적정일 경우, 2005년도와 2007년도 전력수급 기본계획의 전력수요는 동일하므로 전원혼합에 변화가 없다. 전력수요를 5% 과대 또는 5% 과소 예측한 경우, 계획된 발전소 건설을 차기 전력수급기본계획 수립시 줄이거나 늘려야 하는데 건설기간이 짧은 LNG 발전소가 그 영향을 받는 것으로 나타났다.

• 한국경영과학회지
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• 제12권1호
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• pp.157-157
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• 1987

Hydro-electric power generation from multi-purpose dams has been playing important roles in the electric power supply network in Korea. Although the total share of hydro power in national electricity supply now becomes very small, the peak-shaving and frequency control capability of hydro power helps the power company enormously in maintaining the quality of power. But since the company that builds and operates the multi-purpose dams in Korea has to sell all the electricity produced to the monopolistic utility, there have been various problems in justifying the investment, designing pricing mechanism, and controlling operations of the power plants. In addition, economic evaluation of the hydro power has been distorted by a variety of reasons and hence it has been very difficult to encourage effective development and utilization of national water resources. To make the problem worse, both parties are public companies with X-inefficiency problems. Thus, changing environment requires to reengineer the system that governs hydro power generation. We address the problems of Korean hydro-electric power generation system in four areas: the investment justification process, the operations decison right of the hydro power plants, the pricing of the purchased-power, and the negotiation of contract revision. Then we propose improvement directions of new hydro-electric power system in view of static and dynamic efficiency, X-inefficiency and equity.

• 자원ㆍ환경경제연구
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• 제11권4호
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• pp.581-608
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• 2002

The electric power industry has played an important role in dramatic economic development in Korea and the electricity has constituted a critical factor sustaining the well-being of the Korean people. This study uses input-output analysis to investigate the role of four electric power sectors (hydroelectric, fossil-fuels, nuclear and non-utility) in the Korean national economy for the period 1985~1998, focusing on four topics: the impacts of electricity supply investments, the electricity supply shortage effects, and the impacts of the rise in electricity rates, and the inter-industry linkage effect. The overall results reveal that non-utility electric sector is superior in terms of the national economy-wide effects to other three sectors throughout the period. Finally, potential uses of the results are illustrated from the perspective of policy instruments and some policy implications are discussed.