• Journal of the Korean Solar Energy Society
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• v.28 no.1
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• pp.51-56
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• 2008

Since the direct normal insolation is a main factor for designing any solar thermal power system, it is necessary to evaluate its characteristics all over the country. We have begun collecting direct normal insolation data since December 1992 at 16 different locations and considerable effort has been made for constructing a standard value from measured data at each station. KIER(Korea Institute of Energy Research)'s new data will be extensively used by solar thermal concentrating system users or designers as well as by research institutes. From the results, we can conclude that 1) Yearly mean $2.67\;kWh/m^2/day$ of the direct normal insolation was evaluated for all days all over the 16 areas in Korea. 2) All day's direct normal insolation of spring and summer were $2.91\;kWh/m^2/day$ and $2.23\;kWHm^2/day$, and for fall and winter their values were $2.78\;kWh/m^2/day$ and $2.77\;kWh/m^2/day$ respectively. So, spring, fall and winter were higher, and summer was lower than the yearly mean value.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.8
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• pp.1137-1144
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• 2015

Accurate and robust load forecasting model is very important in power system operation. In case of short-term electric load forecasting, its result is offered as an standard to decide a price of electricity and also can be used shaving peak. For this reason, various models have been developed to improve forecasting accuracy. In order to achieve accurate forecasting result for summer season, this paper proposes a forecasting model using corrected effective temperature based on Heat Index and CDH data as inputs. To do so, we establish polynomial that expressing relationship among CDH, load, temperature. After that, we estimate parameters that is multiplied to each of the terms using PSO algorithm. The forecasting results are compared to Holt-Winters and Artificial Neural Network. Proposing method shows more accurate by 1.018%, 0.269%, 0.132% than comparison groups, respectively.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2714-2719
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• 2007

HANARO, an open-tank-in-pool type research reactor of 30 MWth power in Korea, has been operating normally since its initial criticality in February, 1995. For the last about ten years, A cooling tower of a secondary cooling system has been operated normally in HANARO. Last year, the cooling tower has been overhauled for preservative maintenance including fills, eliminators, wood support, water distribution system, motors, driving shafts, gear reducers, basements, blades and etc. This paper describes the results of the overhaul. As results, it is confirmed that the cooling tower maintains a good operability through a filed test. And a cooling capability will be tested when a wet bulb temperature is maintained about 28 $^{\circ}C$ in summer and the reactor is operated with the full power.

• Journal of Advanced Marine Engineering and Technology
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• v.15 no.5
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• pp.38-46
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• 1991

In the design of an electric power plant, the capacity to meet the peak load demand is one of the important factors to be considered. This peak load usually occurs when the most of the cooling air-conditioning systems are being operated during daytime in summer season. Therefore, it is necessary to construct an additional electric power plant and to develop the new air-conditioning system for relieving the peak load. This paper analysed the performance characteristics of this experimental regenerative ice energy system by means of a bundle of the heat-pipes. And the result of this analysis was applied to the simulation of an air-conditioning system model. Also, an operation program of moisture air was made according to air load and in order to computerize the air-conditioning system a CAD program was developed by the properties of moisture air.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1286-1287
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• 2011

최근 친환경 교통수단중 하나인 전기자동차 보급을 위한 정부정책이 강화되고, 관련연구개발 및 시범사업, 실증이 이루어지고 있다. 하지만 아직까지 국내에서는 본격적인 전기자동차 생산단계에 이르지 못하고 있고, 전기자동차 배터리에 전력을 공급하는 충전인프라 구축도 미흡한 실정이다. 전기자동차와 충전인프라는 마치 일반자동차와 주유소와의 관계와 비슷하여 전기자동차 운행을 위해 충전인프라 구축은 필수적이다. 그런데 보통 충전인프라는 전력계통, 충전기와 운영시스템 등으로 구분할 수 있다. 이 가운데 충전기는 전력을 계통으로부터 수전 받아 차량의 배터리에 공급하는 역할을 담당하며, 특히 급속 충전기의 경우 380V, 85의 교류전력을 수전하여 최대 110A, 450V 직류를 공급하는 관계로 충전 중 내부온도관리가 중요하다. 이를 관리하기 위해 적절한 냉방설비 확보, 충전전력 조정 혹은 발열원(부품) 개선 등의 방법이 있으며 이에 관해 상세히 논해보고자 한다.

• Proceedings of the KIEE Conference
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• 2008.11a
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• pp.25-27
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• 2008

전력거래소는 매년 여름철 최대부하 계통을 포함해저 설비의 신증설 등 계통 변경사항이 발생하면 "전력계통 신뢰도 및 전기품질 유지기준"(지경부 고시, 2005. 11월 개정)을 만족하도록 운영방안을 수립하고 있다. 여기에는 전력계통 망의 구성방안, 융통한계량, 과도 및 전압안정도를 유지하기 위한 고장파급 방지장치의 운영방안 결정, 상정고장이 발생 했을 때의 조치방안 등을 포함한다. 이와 같은 계통운영방안을 보다 신뢰성 있게 수립하기 위해서는 우리나라 계통의 특성을 정확히 파악하는 일이 무엇보다 중요하다. 본 고는 올 하절기 최대부하 기간의 계통운영 실적자료를 이용하여 우리나라 계통의 특성을 분석하고, 실적계통의 최적화된 결과와 비교하여 운영개선방안을 도출하고자 한다. 검토결과는 향후 계통운영방안 수립을 위한 기초자료로 활용될 예정이다.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.58 no.1
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• pp.90-94
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• 2009

The inundation of substation and ground power equipment breaks out every summer season in low-lying downtown and low-lying shore by localized heavy rain, typhoon and tidal wave. For diminishing flood damage of electrical equipment in the root, flood protection system which is used the basic frame of Pad transformer is developed using pneumatic pressure. This system is established on pressure generator equipment and sensor of flooded level operates at flooding occurrence and is maintained a shutting tightly structure. The system is able to protect indraft water in Pad Transformer and supply the electricity at emergency(flooding). And we tested safety for insulation resistance at flooding and applying an electrical current. We estimate that loss cost which is caused by with flooding and the power failure will be diminished if it is addition to advances the reliability evaluation by setting an example.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.3
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• pp.27-32
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• 2010

The inundation of substation and ground power equipment breaks out every summer season in low-lying downtown areas and low-lying shores by torrential rain, typhoons and tsunamis. It has, in turn, caused replacement, social and economic costs for blackouts. For activity management regarding flood damage we produced a flood protection system which using the Pad transformer as a basic frame and is developed using pneumatic pressure. We tested safety concerns including insulation resistance and current leakage first for water tank flooding and, second, by an empirical test through supplying 22.9[kV]. We estimate that costs associated with flooding and power failure can be diminished by these advances toward creating a more reliable system.

• Proceedings of the KIEE Conference
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• 2000.11a
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• pp.20-22
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• 2000

The transmission networks are not perfect conductors and a percentage of the power generated is therefore lost before it reaches the loads. This network loss contributes to the cost of suppling power to consumers, and must be considered if the most efficient dispatch and location of generators and loads is to be achieved. In this paper, we propose an approximate calculation of marginal loss factors to analyze characteristics of regional transmission loss. These static marginal loss factors are approximately calculated based on the KEPCO's expected summer peak load data of year 2000.

• Proceedings of the KIEE Conference
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• 2001.07a
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• pp.60-64
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• 2001

Recent recovery of the Korean economy drives a rapid increase in utility consumption and requires more stable utility supply and maintenance. However, power location security hardship, reinforcement of international environmental regulation and a huge cost of power plant construction have increased the burden laid on the stable supply. In addition, an efficient and flexible load management is required more than any era since an increment of the rate of increase in cooling load is expected. Therefore, according as the necessity of direct load control for cooling load during the summer in Korea was on the rise, direct load control systems by Internet communication method are constructed at five commercial buildings. Based on practical load control, this study proposes various application modes and communication methods prior to extension diffusion of direct load control hereafter.