• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.19-20
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• 2008

IEC 61850 is a new approach international standard which is applicable to Substation Automation System (SAS) and defines the communication between intelligent electric devices (IEDs) in the substation and the related system requirements. It already has a significant impact on the development of different devices or systems used in substation. Conformance claims and the establishment of their validity are important parts of the acceptance of systems and equipment. This paper introduces the conformance testing, mapping of IEC 61850 services and MMS services, and in case study part it gives the example of testing OCR IED.

• 전기학회논문지
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• 제65권1호
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• pp.9-15
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• 2016

Distribution networks are operated in radial fashion during the normal state. Loop configuration is also required temporally in case of live load transfer among the adjacent feeders. Voltage angles of each substation buses are very important data in order to calculate power flow of the loop structured distribution feeders. This paper proposes substation bus voltage angle calculation method using voltage angle difference measured at the normally open tie switches. Simulation case studies using Matlab simulink have been performed to establish feasibility of proposed method.

• 전기학회논문지
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• 제64권4호
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• pp.640-645
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• 2015

Near surface transit system has should be constructed as installation cost of light rail transit with elevated track. So, distance between two substations is longer than conventional system. The long feeding distance results in severe voltage drop. This paper proposes a PWM rectifier instead of diode rectifier. The PWM rectifier has some advantages. This is able to control output voltage constantly to reduce voltage drop and to use regeneration power without additional inverter. This paper analyse on improved voltage profile and cost of substation with PWM rectifier. The analysis of voltage profile use PSIM, and the installation cost of substation with PWM rectifier is compared to substation with diode rectifier.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.575-577
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• 2005

KEPCO has developed Transmission & Substation Geographic Information System(TGIS) since 2000. TGIS is the system for the management of transmission and substation facilities on the geographic basis. This paper provides a brief introduction to TGIS.

• 전기학회논문지
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• 제63권11호
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• pp.1608-1614
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• 2014

Power demand forecasting is an important factor of the peak management. This paper deals with the 15 minutes ahead load forecasting problem in a DC urban railway system. Since supplied power lines to trains are connected with parallel, the load characteristics are too complex and highly non-linear. The main idea of the proposed method for the 15 minutes ahead prediction is to use the daily load similarity accounting for the load nonlinearity. An Euclidean norm with weighted factors including loads of the neighbor substation is used for the similar load selection. The prediction value is determinated by the sum of the similar load and the correction value. The correction has applied the neural network model. The feasibility of the proposed method is exemplified through some simulations applied to the actual load data of Incheon subway system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부A
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• pp.295-297
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• 1998

This paper shows characteristics of fault current division factor $S_f$, which is a ratio of earth- return current to total fault current, at a substation fed exclusively by power cables under unsymmetrical fault condition, such as single line-to-ground fault. In substation grounding system design, $S_f$ is a very important factor determining GPR, touch and step voltage at a substation under fault condition. In case of substations fed by overhead lines, 40-60% of $S_f$ has been typically used, although it is a very conservative value with no other network conditions considered. It is authors' hope that $S_f$ presented in this paper could hopefully be a basic reference in designing of substation grounding system, especially for a substation fed exclusively by power cables.

• 전기학회논문지
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• 제57권5호
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• pp.767-772
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• 2008

Korea Electric Power Research Institute in charge of the power IT project "Development of Prototype for Advanced Substation Automation System based on the Digital Control Technology", is performing the verification of performance of the substation automation system. In order to verify a system based BUS protection IED, the standardized document and procedures are required. But there is nothing to describe systematically how to verify IEC 61850 based IED in the system environment except an individual IED testing way and report. This paper presents the substation automation system based ways and procedures to verify the IED using UML(Unified Modelling Language).

• 전기학회논문지
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• 제57권9호
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• pp.1500-1506
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• 2008

In this paper, we proposed new reliability characteristic curve, which-can clearly show reliability property of transmission and substation system considering uncertainty such as frequency and duration of device fault. It express the relationship of duration of load curtailments, demand not supplied, and energy not served as “ y = $ax^{-1}$ " curve. and we proposed the method, which can objectively assess reliability of transmission and substation system using proposed characteristic curve as new reliability index. In this method, we used energy index of reliability(EIR) as a criterion of assessment. Finally, we performed a variety of case study for KEPCO system in order to verify usefulness of proposed method.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.445-450
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• 2008

The primary role of traction power systems is to provide reliable and continuous electrical energy to satisfy traction loads. AC traction substation transforms power from generation company and supply the power to the electric railway power line. Forced outage rate(FOR) of the equipment of substation should be used in the evaluation. This paper proposes the fast and easy way to evaluate by using Bayes' theory when a new equipment is added to the existing substation facility.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 추계학술대회 논문집 전력기술부문
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• pp.388-390
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• 2008

This paper discusses the effect according to the change of grounding system modeling in substation. Substation grounding system is modelled by CDEGS and EMTP. Node voltages of grounding system is variously analysed by 3 grounding cases and 4 kinds of transient frequency ranges. The results of this paper will contribute to advance the grounding system modeling of substation in the range of high frequency transient such as lightning surge.